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Sample records for airborne visible infrared

  1. Visible and infrared linear detector arrays for the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Bailey, Gary C.

    1987-01-01

    The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) instrument uses four separate focal plane assemblies consisting of line array detectors that are multiplexed to a common J-FET preamp using a FET switch multiplexing (MUX) technique. A 32-element silicon line array covers the spectral range from 0.41 to 0.70 microns. Three additional 64-element indium antimonide (InSb) line arrays cover the spectral range from 0.68 to 2.45 microns. The spectral sampling interval per detector element is nominally 9.8 nm, giving a total of 224 spectral channels. All focal planes operate at liquid nitrogen temperature and are housed in separate dewars. Electrical performance characteristics include a read noise of less than 1000 e(-) in all channels, response and dark nonuniformity of 5 percent peak to peak, and quantum efficiency of greater than 60 percent.

  2. Validation of Airborne Visible-Infrared Imaging Spectrometer Data at Ray Mine, AZ

    NASA Technical Reports Server (NTRS)

    Lang, H.; Baloga, S.

    1999-01-01

    We validate 1997 Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) reflectance spectra covering 0.4 meu - 2.4 meu from a stable, flat mineralogically characterized man-made target at Ray Mine, AZ, the site for an EPA/NASA assessment of the utility of remote sensing for monitoring acid drainage from an active open pit mine.

  3. First results from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Vane, Gregg

    1987-01-01

    After engineering flights aboard the NASA U-2 research aircraft in the winter of 1986 to 1987 and spring of 1987, extensive data collection across the United States was begun with the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) in the summer of 1987 in support of a NASA data evaluation and technology assessment program. This paper presents some of the first results obtained from AVIRIS. Examples of spectral imagery acquired over Mountain View and Mono Lake, California, and the Cuprite Mining District in western Nevada are presented. Sensor performance and data quality are described, and in the final section of this paper, plans for the future are discussed.

  4. Atmospheric water mapping with the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), Mountain Pass, California

    NASA Technical Reports Server (NTRS)

    Conel, James E.; Green, Robert O.; Carrere, Veronique; Margolis, Jack S.; Alley, Ronald E.; Vane, Gregg; Bruegge, Carol J.; Gary, Bruce L.

    1988-01-01

    Observations are given of the spatial variation of atmospheric precipitable water using the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) over a desert area in eastern California, derived using a band ratio method and the 940 nm atmospheric water band and 870 nm continuum radiances. The ratios yield total path water from curves of growth supplied by the LOWTRAN 7 atmospheric model. An independent validation of the AVIRIS-derived column abundance at a point is supplied by a spectral hygrometer calibrated with respect to radiosonde observations. Water values conform to topography and fall off with surface elevation. The edge of the water vapor boundary layer defined by topography is thought to have been recovered. The ratio method yields column abundance estimates of good precision and high spatial resolution.

  5. New calibration techniques for the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Chrien, Thomas G.; Green, Robert O.; Chovit, Chris; Eastwood, Mike; Faust, Jessica; Hajek, Pavel; Johnson, Howell; Novack, H. Ian; Sarture, Charles

    1995-01-01

    Recent laboratory calibrations of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) include new methods for the characterization of the geometric, spectral, temporal and radiometric properties of the sensor. New techniques are desired in order to: (1) increase measurement accuracy and precision, (2) minimize measurement time and expense, (3) prototype new field and inflight calibration systems, (4) resolve measurement ambiguities, and (5) add new measurement dimensions. One of the common features of these new methods is the use of the full data collection and processing power of the AVIRIS instrument and data facility. This allows the collection of large amounts of calibration data in a short period of time and is well suited to modular data analysis routines.

  6. Evaluation of Airborne Visible/Infrared Imaging Spectrometer Data of the Mountain Pass, California carbonatite complex

    NASA Technical Reports Server (NTRS)

    Crowley, James; Rowan, Lawrence; Podwysocki, Melvin; Meyer, David

    1988-01-01

    Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data of the Mountain Pass, California carbonatite complex were examined to evaluate the AVIRIS instrument performance and to explore alternative methods of data calibration. Although signal-to-noise estimates derived from the data indicated that the A, B, and C spectrometers generally met the original instrument design objectives, the S/N performance of the D spectrometer was below expectations. Signal-to-noise values of 20 to 1 or lower were typical of the D spectrometer and several detectors in the D spectrometer array were shown to have poor electronic stability. The AVIRIS data also exhibited periodic noise, and were occasionally subject to abrupt dark current offsets. Despite these limitations, a number of mineral absorption bands, including CO3, Al-OH, and unusual rare earth element bands, were observed for mine areas near the main carbonatite body. To discern these bands, two different calibration procedures were applied to remove atmospheric and solar components from the remote sensing data. The two procedures, referred to as the single spectrum and the flat field calibration methods gave distinctly different results. In principle, the single spectrum method should be more accurate; however, additional fieldwork is needed to rigorously determine the degree of calibration success.

  7. Evaluation of the airborne visible-infrared imaging spectrometer for mapping subtle lithological variation

    NASA Technical Reports Server (NTRS)

    Kruse, Fred A.

    1990-01-01

    The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), flown aboard the NASA ER-2 aircraft in 1987 and 1989, used four linear arrays and four individual spectrometers to collect data simultaneously from the 224 bands in a scanned 614 pixel-wide swath perpendicular to the aircraft direction. The research had two goals. One was to evaluate the AVIRIS data. The other was to look at the subtle lithological variation at the two test sites to develop a better understanding of the regional geology and surficial processes. The geometric characteristics of the data, adequacy of the spatial resolution, and adequacy of the spectral sampling interval are evaluated. Geologic differences at the test sites were mapped. They included lithological variation caused by primary sedimentary layering, facies variation, and weathering; and subtle mineralogical differences caused by hydrothermal alterations of igneous and sedimentary rocks. The investigation used laboratory, field, and aircraft spectral measurements; known properties of geological materials; digital image processing and spectrum processing techniques; and field geologic data to evaluate the selected characteristics of the AVIRIS data.

  8. Geometric and radiometric preprocessing of airborne visible/infrared imaging spectrometer (AVIRIS) data in rugged terrain for quantitative data analysis

    NASA Technical Reports Server (NTRS)

    Meyer, Peter; Green, Robert O.; Staenz, Karl; Itten, Klaus I.

    1994-01-01

    A geocoding procedure for remotely sensed data of airborne systems in rugged terrain is affected by several factors: buffeting of the aircraft by turbulence, variations in ground speed, changes in altitude, attitude variations, and surface topography. The current investigation was carried out with an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) scene of central Switzerland (Rigi) from NASA's Multi Aircraft Campaign (MAC) in Europe (1991). The parametric approach reconstructs for every pixel the observation geometry based on the flight line, aircraft attitude, and surface topography. To utilize the data for analysis of materials on the surface, the AVIRIS data are corrected to apparent reflectance using algorithms based on MODTRAN (moderate resolution transfer code).

  9. Use of high spectral resolution airborne visible/infrared imaging spectrometer data for geologic mapping: An overview

    NASA Technical Reports Server (NTRS)

    Carrere, Veronique

    1991-01-01

    Specific examples of the use of AVIRIS (Airborne Visible/Infrared Imaging Spectrometer) high spectral resolution data for mapping, alteration related to ore deposition and to hydrocarbon seepage, and alluvial fans are presented. Correction for atmospheric effects was performed using flat field correction, log residuals, and radiative transfer modeling. Minerals of interest (alunite, kaolinite, gypsum, carbonate iron oxides, etc.) were mapped based upon the wavelength position, depth and width of characteristic absorption features. Results were checked by comparing to existing maps, results from other sensors (Thematic Mapper (TM) and TIMS (Thermal Infrared Multispectral Scanner)), and laboratory spectra of samples collected in the field. Alteration minerals were identified and mapped. The signal to noise ratio of acquired AVIRIS data, long to 2.0 microns, was insufficient to map minerals of interest.

  10. Near-infrared extension of a visible spectrum airborne Sun photometer

    NASA Astrophysics Data System (ADS)

    Starace, Marco; von Bismarck, Jonas; Hollstein, André; Ruhtz, Thomas; Preusker, René; Fischer, Jürgen

    2013-05-01

    The continuously-measuring, multispectral airborne Sun and aureole photometers FUBISS-ASA and FUBISSASA2 were developed at the Institute for Space Sciences of the Freie Universität Berlin in 2002 and 2006 respectively, for the retrieval of aerosol optical and microphysical parameters at wavelengths ranging from 400 to 900 nm. A multispectral near-infrared direct sun radiometer measuring in a spectral range of 1000 to 1700 nm has now been added to FUBISS-ASA2. The main objective of this NIR extension is to enhance the characterization of larger aerosol particles, as Mie scattering theory offers a more accurate approximation for their interaction with electromagnetic radiation, if both the VIS and NIR parts of the spectrum are considered, than it does for the VIS part only. The spectral transmissivity of atmospheric models was computed using the HITRAN2008 database in order to determine local absorption minima suitable for aerosol retrieval. Measurements were first carried out aboard the research vessel FS Polarstern on its transatlantic voyage ANT-XXVI/1. Additional measurements were performed from the Sphinx High Altitude Research Station on the Jungfraujoch and in the nearby Kleine Scheidegg locality during the CLACE2010 measurement campaign. Aerosol optical parameters derived from VIS aureole and direct sun measurements were compared to those of simulated aerosol mixtures in order to estimate the composition of the measured aerosol.

  11. MODIS airborne simulator visible and near-infrared calibration, 1992 ASTEX field experiment. Calibration version: ASTEX King 1.0

    NASA Technical Reports Server (NTRS)

    Arnold, G. Thomas; Fitzgerald, Michael; Grant, Patrick S.; King, Michael D.

    1994-01-01

    Calibration of the visible and near-infrared (near-IR) channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1992 Atlantic Stratocumulus Transition Experiment (ASTEX) field deployment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Tests during the ASTEX deployment were conducted to calibrate the hemisphere and then the MAS. This report summarizes the ASTEX hemisphere calibration, and then describes how the MAS was calibrated from the hemisphere data. All MAS calibration measurements are presented and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. In addition, comparisons to an independent MAS calibration by Ames personnel using their 30-inch integrating sphere is discussed.

  12. A comparison of LOWTRAN-7 corrected Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data with ground spectral measurements

    NASA Technical Reports Server (NTRS)

    Xu, Peng-Yang; Greeley, Ronald

    1992-01-01

    Atmospheric correction of imaging spectroscopy data is required for quantitative analysis. Different models were proposed for atmospheric correction of these data. LOWTRAN-7 is a low-resolution model and computer code for predicting atmospheric transmittance and background radiance from 0 to 50,00 cm(sup -1) which was developed by the Air Force Geophysics Laboratory. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data used are radiometrically calibrated and include the 28 Sep. 1989 Providence Fan flight line segment 07, California. It includes a dark gravel surface defined as a calibration site by the Geologic Remote Sensing Field Experiment (GRSFE). Several ground measurements of portable spectrometer DAEDALUS AA440 Spectrafax were taken during the GRSFE, July 1989 field campaign. Comparisons of the LOWTRAN-7 corrected AVIRIS data with the ground spectrometer measurement were made.

  13. Recovery of Atmospheric Water Vapor Total Column Abundance from Imaging Spectrometer Data Around 940 nm - Sensitivity Analysis and Application to Airborne Visible/Infrared Imaging Spectrometer (AVIRI

    NASA Technical Reports Server (NTRS)

    Carrere, V.; Conel, J. E.

    1993-01-01

    Twosimple techniques to retrieve path precipitable water fromthe Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) high spectral resolution radiance data (Continuum Interpolated Band Ratio, CIBR, and Narrow/Wide Ratio, N/W), using the 940 nm water absorption band, are compared.

  14. Mapping methane concentrations from a controlled release experiment using the next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRISng)

    NASA Astrophysics Data System (ADS)

    Thorpe, A. K.; Frankenberg, C.; Roberts, D. A.; Aubrey, A. D.; Green, R. O.; Hulley, G. C.; Hook, S. J.

    2014-12-01

    Airborne imaging spectrometers like the next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRISng) are well suited for monitoring local methane sources by covering large regions with the high spatial resolution necessary to resolve emissions. As part of a field campaign with controlled methane releases at the Rocky Mountain Oilfield Testing Center (RMOTC), a number of methane plumes were clearly visible at multiple flux rates and flight altitudes. Images of plumes appeared consistent with wind directions measured at ground stations and were present for fluxes as low as 14.2 cubic meters of methane per hour, equivalent to 0.09 kt/year. Direct comparison of results from AVIRISng and plume dispersion models is ongoing and will be used to assess the potential of constraining emission fluxes using AVIRISng. Methane plumes observed at RMOTC with the Hyperspectral Thermal Emission Spectrometer (HyTES) will also be presented. This controlled release experiment was used to determine the methane sensitivity of AVIRISng and inform sensor design for future imaging spectrometers that could constrain natural and anthropogenic methane emissions on local and regional scales. Imaging spectrometers permit direct attribution of emissions to individual point sources which is particularly useful given the large uncertainties associated with anthropogenic emissions, including industrial point source emissions and fugitive methane from the oil and gas industry. Figure caption: a. AVIRISng true color image indicating tube trailer (TT), meteorological tower (MT), and release point (RP). b. Prominent methane plume and measured enhancements for 70.8 cubic meters per hour methane flux is consistent with wind speed and direction (see arrow) measured by meteorological tower. A linear transect is shown in red and corresponds to enhancements shown in c. d. True color image showing release point (RP). e. Smaller methane plume for 14.2 cubic meters per hour flux. f. Methane

  15. Airborne Multiangle SpectroPolarimeteric Imager (AirMSPI): Calibration and Comparison with Collocated Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) Data

    NASA Astrophysics Data System (ADS)

    Seidel, F. C.; Diner, D. J.; Bruegge, C. J.; Rheingans, B. E.; Garay, M. J.; Daugherty, B. J.; Chipman, R. A.; Davis, A.

    2014-12-01

    The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) is a pushbroom multiangle spectropolarimetric camera with spectral bands near 355, 380, 445, 470, 555, 660, 865, and 935 nm. Flying on NASAs's high-altitude ER-2 aircraft since 2010, AirMSPI uses dual photoelastic modulator (PEM)-based technology to provide accurate measurements of the Stokes linear polarization parameters Q and U in the 470, 660, and 865 nm bands, providing unique observing capabilities for aerosol, cloud, and surface studies. We describe the methodologies used for radiometric and polarimetric calibration and characterization of the AirMSPI instrument, which make use of a combination of laboratory and vicarious techniques. A 1.65 m integrating sphere and overflights of Ivanpah Playa, NV are used for radiometric calibration. Radiometric cross-comparisons with the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), also flying on the ER-2, are used to validate the radiometric scale. For polarimetric calibration, a well-calibrated Polarization State Generator is used to provide known polarimetric inputs. A high-extinction rotating wiregrid polarizer is used to derive polarimetric calibration coefficients for each pixel, and the results are then validated using partially polarized light generated using tilted glass plates. Examples of collocated multiangular, polarimetric imagery from AirMSPI and hyperspectral imagery from AVIRIS will be shown, presenting new opportunities for atmosphere and surface remote sensing.

  16. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). A description of the sensor, ground data processing facility, laboratory calibration, and first results

    NASA Technical Reports Server (NTRS)

    Vane, Gregg (Editor)

    1987-01-01

    The papers in this document were presented at the Imaging Spectroscopy 2 Conference of the 31st International Symposium on Optical and Optoelectronic Applied Science and Engineering, in San Diego, California, on 20 and 21 August 1987. They describe the design and performance of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) sensor and its subsystems, the ground data processing facility, laboratory calibration, and first results.

  17. Infrared: Beyond the Visible

    NASA Video Gallery

    Infrared: Beyond the Visible, is a fast, fun look at why infrared light matters to astronomy, and what the Webb Space Telescope will search for once it's in orbit. Caption file available at: http:/...

  18. Mapped minerals at Questa, New Mexico, using airborne visible-infrared imaging spectrometer (AVIRIS) data -- Preliminary report

    USGS Publications Warehouse

    Livo, K. Eric; Clark, Roger N.

    2002-01-01

    This preliminary study for the First Quarterly Report has spectrally mapped hydrothermally altered minerals useful in assisting in assessment of water quality of the Red River. Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) data was analyzed to characterize mined and unmined ground at Questa, New Mexico. AVIRIS data covers the Red River drainage north of the river, from between the town of Questa on the west, to east of the town of Red River. The data was calibrated and analyzed using U.S. Geological Survey custom software and spectral mineral library. AVIRIS data was tested for spectral features that matched similar features in the spectral mineral library. Goodness-of-fit and band-depth were calculated for each comparison of spectral features and used to identify surface mineralogy. Mineral distribution, mineral associations, and AVIRIS pixel spectra were examined. Mineral maps show the distribution of iron hydroxides, iron sulfates, clays, micas, carbonates, and other minerals. Initial results show a system of alteration suites that overprint each other. Quartz-sericite-pyrite (QSP) alteration grading out to propylitic alteration (epidote and calcite) was identified at the Questa Mine (molybdenum porphyry) and a similar alteration pattern was mapped at the landslide (?scar?) areas. Supergene weathering overprints the altered rock, as shown by jarosite, kaolinite, and gypsum. In the spectral analysis, hydrothermally altered ground appears to be more extensive at the unmined Goat Hill Gulch and the mined ground, than the ?scars? to the east. Though the ?scars? have similar overall altered mineral suites, there are differences between the ?scars? in sericite, kaolinite, jarosite, gypsum, and calcite abundance. Fieldwork has verified the results at the central unmined ?scar? areas.

  19. Mapping Weathering and Alteration Minerals in the Comstock and Geiger Grade Areas using Visible to Thermal Infrared Airborne Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Vaughan, Greg R.; Calvin, Wendy M.

    2005-01-01

    To support research into both precious metal exploration and environmental site characterization a combination of high spatial/spectral resolution airborne visible, near infrared, short wave infrared (VNIR/SWIR) and thermal infrared (TIR) image data were acquired to remotely map hydrothermal alteration minerals around the Geiger Grade and Comstock alteration regions, and map the mineral by-products of weathered mine dumps in Virginia City. Remote sensing data from the Airborne Visible Infrared Imaging Spectrometer (AVIRIS), SpecTIR Corporation's airborne hyperspectral imager (HyperSpecTIR), the MODIS-ASTER airborne simulator (MASTER), and the Spatially Enhanced Broadband Array Spectrograph System (SEBASS) were acquired and processed into mineral maps based on the unique spectral signatures of image pixels. VNIR/SWIR and TIR field spectrometer data were collected for both calibration and validation of the remote data sets, and field sampling, laboratory spectral analyses and XRD analyses were made to corroborate the surface mineralogy identified by spectroscopy. The resulting mineral maps show the spatial distribution of several important alteration minerals around each study area including alunite, quartz, pyrophyllite, kaolinite, montmorillonite/muscovite, and chlorite. In the Comstock region the mineral maps show acid-sulfate alteration, widespread propylitic alteration and extensive faulting that offsets the acid-sulfate areas, in contrast to the larger, dominantly acid-sulfate alteration exposed along Geiger Grade. Also, different mineral zones within the intense acid-sulfate areas were mapped. In the Virginia City historic mining district the important weathering minerals mapped include hematite, goethite, jarosite and hydrous sulfate minerals (hexahydrite, alunogen and gypsum) located on mine dumps. Sulfate minerals indicate acidic water forming in the mine dump environment. While there is not an immediate threat to the community, there are clearly sources of

  20. Infrared airborne spectroradiometer survey results in the western Nevada area

    NASA Technical Reports Server (NTRS)

    Collins, W.; Chang, S. H.; Kuo, J. T.

    1982-01-01

    The Mark II airborne spectroradiometer system was flown over several geologic test sites in western Nevada. The infrared mineral absorption bands were observed and recorded for the first time using an airborne system with high spectral resolution in the 2.0 to 2.5 micron region. The data show that the hydrothermal alteration zone minerals, carbonates, and other minerals are clearly visible in the airborne survey mode. The finer spectral features that distinguish the various minerals with infrared bands are also clearly visible in the airborne survey data. Using specialized computer pattern recognition methods, it is possible to identify mineralogy and map alteration zones and lithologies by airborne spectroradiometer survey techniques.

  1. Expert system-based mineral mapping in northern Death Valley, California/Nevada, using the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Kruse, F. A.; Lefkoff, A. B.; Dietz, J. B.

    1993-01-01

    Integrated analysis of imaging spectrometer data and field spectral measurements were used in conjunction with conventional geologic field mapping to characterize bedrock and surficial geology at the northern end of Death Valley, California and Nevada. A knowledge-based expert system was used to automatically produce image maps showing the principal surface mineralogy from Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data. Linear spectral unmixing of the AVIRIS data allowed further determination of relative mineral, abundances and identification of mineral assemblages and mixtures. The imaging spectrometer data show the spatial distribution of spectrally distinct minerals occurring both as primary rockforming minerals and as alteration and weathering products. Field spectral measurements were used to verify the mineral maps and field mapping was used to extend the remote sensing results. Geographically referenced image maps produced from these data form new base maps from which to develop improved understanding of the processes of deposition and erosion affecting the present land surface.

  2. Use of the Airborne Visible/Infrared Imaging Spectrometer to calibrate the optical sensor on board the Japanese Earth Resources Satellite-1

    NASA Technical Reports Server (NTRS)

    Green, Robert O.; Conel, James E.; Vandenbosch, Jeannette; Shimada, Masanobu

    1993-01-01

    We describe an experiment to calibrate the optical sensor (OPS) on board the Japanese Earth Resources Satellite-1 with data acquired by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). On 27 Aug. 1992 both the OPS and AVIRIS acquired data concurrently over a calibration target on the surface of Rogers Dry Lake, California. The high spectral resolution measurements of AVIRIS have been convolved to the spectral response curves of the OPS. These data in conjunction with the corresponding OPS digitized numbers have been used to generate the radiometric calibration coefficients for the eight OPS bands. This experiment establishes the suitability of AVIRIS for the calibration of spaceborne sensors in the 400 to 2500 nm spectral region.

  3. MODIS airborne simulator visible and near-infrared calibration, 1991 FIRE-Cirrus field experiment. Calibration version: FIRE King 1.1

    NASA Technical Reports Server (NTRS)

    Arnold, G. Thomas; Fitzgerald, Michael; Grant, Patrick S.; King, Michael D.

    1994-01-01

    Calibration of the visible and near-infrared channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1991 FIRE-Cirrus field experiment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Laboratory tests during the FIRE Cirrus field experiment were conducted to calibrate the hemisphere and from the hemisphere to the MAS. The purpose of this report is to summarize the FIRE-Cirrus hemisphere calibration, and then describe how the MAS was calibrated from observations of the hemisphere data. All MAS calibration measurements are presented, and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. Thermal sensitivity of the MAS visible and near-infrared calibration is also discussed. Typically, the MAS in-flight is 30 to 60 degrees C colder than the room temperature laboratory calibration. Results from in-flight temperature measurements and tests of the MAS in a cold chamber are given, and from these, equations are derived to adjust the MAS in-flight data to what the value would be at laboratory conditions. For FIRE-Cirrus data, only channels 3 through 6 were found to be temperature sensitive. The final section of this report describes comparisons to an independent MAS (room temperature) calibration by Ames personnel using their 30-inch integrating sphere.

  4. Infrared and visible cooperative vehicle identification markings

    NASA Astrophysics Data System (ADS)

    O'Keefe, Eoin S.; Raven, Peter N.

    2006-05-01

    Airborne surveillance helicopters and aeroplanes used by security and defence forces around the world increasingly rely on their visible band and thermal infrared cameras to prosecute operations such as the co-ordination of police vehicles during the apprehension of a stolen car, or direction of all emergency services at a serious rail crash. To perform their function effectively, it is necessary for the airborne officers to unambiguously identify police and the other emergency service vehicles. In the visible band, identification is achieved by placing high contrast symbols and characters on the vehicle roof. However, at the wavelengths at which thermal imagers operate, the dark and light coloured materials have similar low reflectivity and the visible markings cannot be discerned. Hence there is a requirement for a method of passively and unobtrusively marking vehicles concurrently in the visible and thermal infrared, over a large range of viewing angles. In this paper we discuss the design, detailed angle-dependent spectroscopic characterisation and operation of novel visible and infrared vehicle marking materials, and present airborne IR and visible imagery of materials in use.

  5. A Parametric Approach for the Geocoding of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) Data in Rugged Terrain

    NASA Technical Reports Server (NTRS)

    Peter, M.

    1993-01-01

    A geocoding procedure for remotely sensed data of airborne systems in rugged terrain is affected by several factors: buffeting of the aircraft by turbulances, variations in ground speed, changes in altitude, attitude variations, and surface topography.

  6. Calibration Of Airborne Visible/IR Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Vane, G. A.; Chrien, T. G.; Miller, E. A.; Reimer, J. H.

    1990-01-01

    Paper describes laboratory spectral and radiometric calibration of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) applied to all AVIRIS science data collected in 1987. Describes instrumentation and procedures used and demonstrates that calibration accuracy achieved exceeds design requirements. Developed for use in remote-sensing studies in such disciplines as botany, geology, hydrology, and oceanography.

  7. Airborne Visible Laser Optical Communications Program (AVLOC)

    NASA Technical Reports Server (NTRS)

    Ward, J. H.

    1975-01-01

    The design, development, and operation of airborne and ground-based laser communications and laser radar hardware is described in support of the Airborne Visible Laser Optical Communication program. The major emphasis is placed on the development of a highly flexible test bed for the evaluation of laser communications systems techniques and components in an operational environment.

  8. Mapping hydrothermally altered rocks on Mount Rainier, Washington, with Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data

    USGS Publications Warehouse

    Crowley, J.K.; Zimbelman, D.R.

    1997-01-01

    Mount Rainier has produced numerous Holocene debris flows, the largest of which contain clays and other minerals derived from hydrothermally altered rocks on the volcano's edifice. Imagery from an advanced airborne sensor was used to map altered rocks at Mount Rainier and demonstrates their distinctly nonuniform distribution. The mapping of altered rocks helps to identify edifice failure surfaces and to recognize the source areas for the largest debris flow events. Remote sensing methods like those used at Mount Rainier can enhance ground-based mapping efforts and should prove useful for rapidly identifying hazardous sectors at other volcanoes.

  9. Lithology and structure within the basement terrain adjacent to Clark Mountains, California, mapped with calibrated data from the airborne visible/infrared imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Green, Robert O.; Vane, Gregg

    The Clark Mountains in eastern California form a rugged, highly dissected area nearly 5000 ft above sea level, with Clark Mountain rising to 8000 ft. The rocks of the Clark Mountains and the Mescal Range just to the south are Paleozoic carbonate and clastic rocks, and Mesozoic clastic and volcanic rocks standing in pronounced relief above the fractured Precambrian gneisses to the east. The Permian Kaibab Limestone and the Triassic Moenkopi and Chinle Formations are exposed in the Mescal Range, which is the only place in California where these rocks, which are typical of the Colorado Plateau, are found. To the west, the mountains are bordered by the broad alluvial plains of Shadow Valley. Cima Dome, which is an erosional remnant carved on a batholithic intrusion of quartz monzonite, is found at the south end of the valley. To the east of the Clark and Mescal Mountains is found the Ivanpah Valley, in the center of which is located the Ivanpah Play. Studies of the Clark Mountains with the airborne visible/infrared imaging spectrometer are briefly described.

  10. Comparison of laboratory calibrations of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) at the beginning and end of the first flight season

    NASA Technical Reports Server (NTRS)

    Vane, Gregg; Chrien, Thomas G.; Reimer, John H.; Green, Robert O.; Conel, James E.

    1988-01-01

    Spectral and radiometric calibrations of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) were performed in the laboratory in June and November, 1987, at the beginning and end of the first flight season. Those calibrations are described along with changes in instrument characteristics that occurred during the flight season as a result of factors such as detachment of the optical fibers to two of the four AVIRIS spectrometers, degradation in the optical alignment of the spectrometers due to thermally-induced and mechanical warpage, and breakage of a thermal blocking filter in one of the spectrometers. These factors caused loss of signal in three spectrometers, loss of spectral resolution in two spectrometers, and added uncertainty in the radiometry of AVIRIS. Results from in-flight assessment of the laboratory calibrations are presented. A discussion is presented of improvements made to the instrument since the end of the first flight season and plans for the future. Improvements include: (1) a new thermal control system for stabilizing spectrometer temperatures, (2) kinematic mounting of the spectrometers to the instrument rack, and (3) new epoxy for attaching the optical fibers inside their mounting tubes.

  11. Directly attributing methane emissions to point source locations using the next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG)

    NASA Astrophysics Data System (ADS)

    Thorpe, A. K.; Thompson, D. R.; Frankenberg, C.; Aubrey, A. D.; Bue, B. D.; Green, R. O.; Kort, E. A.; Eastwood, M. L.; Helmlinger, M. C.; Nolte, S. H.

    2015-12-01

    Imaging spectrometers like the next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) are well suited for identifying methane point sources by covering large regions with the high spatial resolution necessary to resolve emissions. A controlled release experiment at the Rocky Mountain Oilfield Testing Center (RMOTC) showed detectable methane plumes at multiple flux rates and flight altitudes. Images of plumes agreed with wind direction measured at ground stations and were consistently present for fluxes as low as 0.09 kt/year (14.16 cubic meters per hour; 500 standard cubic feet per hour, scfh). In some cases plumes were detected as low as 0.02 kt/year (3.40 cubic meters per hour; 120 scfh), indicating that AVIRIS-NG has the capability of detecting a number of fugitive methane source categories for natural gas fields. Following the RMOTC campaign, real time detection and geolocation of methane plumes has been implemented using an operator interface that overlays plumes on a true color image acquired by AVIRIS-NG. This has facilitated surveys over existing oil and gas fields to identify and attribute methane emissions to individual point source locations, including well pads known to use hydraulic fracturing and natural gas pipelines. An imaging spectrometer built exclusively for detection, quantification, and attribution of methane plumes would have improved sensitivity compared to AVIRIS-NG. The Airborne Methane Plume Spectrometer (AMPS) instrument concept is mature, ready for development, and would provide a spectral resolution of 1 nm and a detection threshold of approximately 0.28 cubic meters per hour (10 scfh). By offering the potential to identify point source locations, airborne imaging spectrometers could have particular utility for resolving the large uncertainties associated with anthropogenic emissions, including industrial point source emissions and fugitive methane from the oil and gas industry. Fig.1: True color image subset with

  12. Reflectance spectra from eutrophic Mono Lake California, measured with the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Melack, John M.; Pilorz, Stuart H.

    1990-01-01

    An AVIRIS image was obtained for Mono Lake, California, on May 26, 1989, a day with excellent visibility. Atmospherically-corrected reflectance spectra derived from the image indicate a spectral signature for chlorophyll a, the dominant photosynthetic pigment in the phytoplankton of the lake. Chlorophyll a concentrations in the lake were about 22 mg/cu m, and the upwelling radiance was low with a peak reflectance at about 570 nm of about 5 percent. Coherent noise appeared in the image as regular variations of 0.1 to 0.2 microwatts/sq cm per str oriented diagonally to the flight line. A simple ratio of two spectral bands removed the conspicuous undulations, but modifications of the shielding within the instrument are needed to improve the signal especially over dark targets such as lakes.

  13. Integrated infrared and visible image sensors

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Pain, Bedabrata (Inventor)

    2000-01-01

    Semiconductor imaging devices integrating an array of visible detectors and another array of infrared detectors into a single module to simultaneously detect both the visible and infrared radiation of an input image. The visible detectors and the infrared detectors may be formed either on two separate substrates or on the same substrate by interleaving visible and infrared detectors.

  14. Airborne thermography or infrared remote sensing.

    PubMed

    Goillot, C C

    1975-01-01

    Airborne thermography is part of the more general remote sensing activity. The instruments suitable for image display are infrared line scanners. A great deal of interest has developed during the past 10 years in airborne thermal remote sensing and many applications are in progress. Infrared scanners on board a satellite are used for observation of cloud cover; airborne infrared scanners are used for forest fire detection, heat budget of soils, detecting insect attack, diseases, air pollution damage, water stress, salinity stress on vegetation, only to cite some main applications relevant to agronomy. Using this system it has become possible to get a 'picture' of our thermal environment.

  15. Visible and infrared imaging radiometers for ocean observations

    NASA Technical Reports Server (NTRS)

    Barnes, W. L.

    1977-01-01

    The current status of visible and infrared sensors designed for the remote monitoring of the oceans is reviewed. Emphasis is placed on multichannel scanning radiometers that are either operational or under development. Present design practices and parameter constraints are discussed. Airborne sensor systems examined include the ocean color scanner and the ocean temperature scanner. The costal zone color scanner and advanced very high resolution radiometer are reviewed with emphasis on design specifications. Recent technological advances and their impact on sensor design are examined.

  16. Regional prediction of soil organic carbon content over temperate croplands using visible near-infrared airborne hyperspectral imagery and synchronous field spectra

    NASA Astrophysics Data System (ADS)

    Vaudour, E.; Gilliot, J. M.; Bel, L.; Lefevre, J.; Chehdi, K.

    2016-07-01

    This study aimed at identifying the potential of Vis-NIR airborne hyperspectral AISA-Eagle data for predicting the topsoil organic carbon (SOC) content of bare cultivated soils over a large peri-urban area (221 km2) with both contrasted soils and SOC contents, located in the western region of Paris, France. Soil types comprised haplic luvisols, calcaric cambisols and colluvic cambisols. Airborne AISA-Eagle data (400-1000 nm, 126 bands) with 1 m-resolution were acquired on 17 April 2013 over 13 tracks. Tracks were atmospherically corrected then mosaicked at a 2 m-resolution using a set of 24 synchronous field spectra of bare soils, black and white targets and impervious surfaces. The land use identification system layer (RPG) of 2012 was used to mask non-agricultural areas, then calculation and thresholding of NDVI from an atmospherically corrected SPOT image acquired the same day enabled to map agricultural fields with bare soil. A total of 101 sites sampled either in 2013 or in the 3 previous years and in 2015 were identified as bare by means of this map. Predictions were made from the mosaic AISA spectra which were related to topsoil SOC contents by means of partial least squares regression (PLSR). Regression robustness was evaluated through a series of 1000 bootstrap data sets of calibration-validation samples, considering 74 sites outside cloud shadows only, and different sampling strategies for selecting calibration samples. Validation root-mean-square errors (RMSE) were comprised between 3.73 and 4.49 g Kg-1 and were ∼4 g Kg-1 in median. The most performing models in terms of coefficient of determination (R2) and Residual Prediction Deviation (RPD) values were the calibration models derived either from Kennard-Stone or conditioned Latin Hypercube sampling on smoothed spectra. The most generalizable model leading to lowest RMSE value of 3.73 g Kg-1 at the regional scale and 1.44 g Kg-1 at the within-field scale and low bias was the cross-validated leave

  17. Seasonal and spatial variations in phytoplanktonic chlorophyll in eutrophic Mono Lake, California, measured with the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Melack, John M.; Gastil, Mary

    1992-01-01

    The principal problem with application of airborne imaging spectrometers to lakes is the weak upwelling signal, especially when narrow spectral bands with high spatial resolution are sought. Furthermore, atmospheric path radiance dominates the signal received from dark targets such as lakes. Once atmospheric effects have been removed from the radiance received at the sensor, semi-empirical relationships can be developed to extract information about phytoplankton pigment concentrations for different underwater optical conditions. In lakes where concentrations of dissolved organics and suspended detritus may not co-vary with phytoplankton pigments, the many spectral channels of an imaging spectrometer such as AVIRIS are likely to be required to distinguish the various aquasols. The objectives of our study are to: (1) estimate the chlorophyll content of a lake with hundred-fold seasonal ranges in chlorophyll concentration using atmospherically corrected upwelling radiances derived from AVIRIS imagery, and (2) to examine spatial patterns in chlorophyll after reduction of the coherent noise in the imagery by filtering techniques.

  18. Recovery of atmospheric water vapor total column abundance from imaging spectrometer data around 940 nm - Sensitivity analysis and application to Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data

    NASA Technical Reports Server (NTRS)

    Carrere, Veronique; Conel, James E.

    1993-01-01

    Two simple techniques (Continuum Interpolated Band Ratio, CIBR, and Narrow/Wide ratio, N/W) to retrieve path precipitable water from AVIRIS high spectral resolution radiance data using the 940 nm water absorption band are compared. A sensitivity analysis was performed using the radiative transfer code LOWTRAN 7 to determine which one of these two approaches will provide a better estimate over land and water areas. The CIBR proved to be the technique less sensitive to perturbing effects, except for errors in visibility estimate. Both techniques were applied to AVIRIS radiance data acquired over Salton Sea, California. Resulting images confirmed that the use of a constant gray reflectance in the model led to a higher overestimation of the amount of water retrieved for N/W over vegetated areas. Validation was performed through comparison between an independent estimate of water vapor from concurrent Reagan sunphotometer measurements and AVIRIS estimates. Amounts retrieved using the N/W approach match more closely in situ measurements, even after adjusting model parameters for background reflectance, viewing geometry, and type of aerosol at the site.

  19. Within-field and regional-scale accuracies of topsoil organic carbon content prediction from an airborne visible near-infrared hyperspectral image combined with synchronous field spectra for temperate croplands

    NASA Astrophysics Data System (ADS)

    Vaudour, Emmanuelle; Gilliot, Jean-Marc; Bel, Liliane; Lefevre, Josias; Chehdi, Kacem

    2016-04-01

    This study was carried out in the framework of the TOSCA-PLEIADES-CO of the French Space Agency and benefited data from the earlier PROSTOCK-Gessol3 project supported by the French Environment and Energy Management Agency (ADEME). It aimed at identifying the potential of airborne hyperspectral visible near-infrared AISA-Eagle data for predicting the topsoil organic carbon (SOC) content of bare cultivated soils over a large peri-urban area (221 km2) with intensive annual crop cultivation and both contrasted soils and SOC contents, located in the western region of Paris, France. Soils comprise hortic or glossic luvisols, calcaric, rendzic cambisols and colluvic cambisols. Airborne AISA-Eagle images (400-1000 nm, 126 bands) with 1 m-resolution were acquired on 17 April 2013 over 13 tracks. Tracks were atmospherically corrected then mosaicked at a 2 m-resolution using a set of 24 synchronous field spectra of bare soils, black and white targets and impervious surfaces. The land use identification system layer (RPG) of 2012 was used to mask non-agricultural areas, then calculation and thresholding of NDVI from an atmospherically corrected SPOT4 image acquired the same day enabled to map agricultural fields with bare soil. A total of 101 sites, which were sampled either at the regional scale or within one field, were identified as bare by means of this map. Predictions were made from the mosaic AISA spectra which were related to SOC contents by means of partial least squares regression (PLSR). Regression robustness was evaluated through a series of 1000 bootstrap data sets of calibration-validation samples, considering those 75 sites outside cloud shadows only, and different sampling strategies for selecting calibration samples. Validation root-mean-square errors (RMSE) were comprised between 3.73 and 4.49 g. Kg-1 and were ~4 g. Kg-1 in median. The most performing models in terms of coefficient of determination (R²) and Residual Prediction Deviation (RPD) values were the

  20. Airborne Infrared Spectroscopy of 1994 Western Wildfires

    NASA Technical Reports Server (NTRS)

    Worden, Helen; Beer, Reinhard; Rinsland, Curtis P.

    1997-01-01

    In the summer of 1994 the 0.07/ cm resolution infrared Airborne Emission Spectrometer (AES) acquired spectral data over two wildfires, one in central Oregon on August 3 and the other near San Luis Obispo, California, on August 15. The spectrometer was on board a NASA DC-8 research aircraft, flying at an altitude of 12 km. The spectra from both fires clearly show features due to water vapor, carbon dioxide, carbon monoxide, ammonia, methanol, formic acid, and ethylene at significantly higher abundance and temperature than observed in downlooking spectra of normal atmospheric and ground conditions. Column densities are derived for several species, and molar ratios are compared with previous biomass fire measurements. We believe that this is the first time such data have been acquired by airborne spectral remote sensing.

  1. Airborne Infrared Spectrograph for Eclipse Observations

    NASA Astrophysics Data System (ADS)

    Golub, L.; Cheimets, P.; DeLuca, E. E.; Samra, J.; Judge, P. G.

    2015-12-01

    Direct measurements of the coronal magnetic field have significant potential to enhance our understanding of coronal dynamics, and improve forecasting models. Of particular interest are observations of coronal field lines in the Transition Corona, the transitional region between closed and open flux systems, providing important information on eruptive instabilities and on the origin of the slow solar wind. While current instruments routinely observe the photospheric and chromospheric magnetic fields, the proposed airborne spectrometer will take a step toward the direct observation of coronal fields by measuring plasma emission in the infrared at high spatial and spectral resolution. The targeted lines are five forbidden magnetic dipole transitions between 1.4 and 4 um. The airborne system will consist of a telescope, grating spectrometer and pointing/stabilization system to be flown on the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) during the 21 August 2017 total solar eclipse. We will discuss the scientific objectives of the 2017 flight, describe details of the instrument design, and present the observing program for the eclipse.

  2. Exploitation of combined visible hyperspectral and infrared imagery

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey B.; Marmorino, George O.; Miller, W. David

    2008-11-01

    Natural and anthropogenic surfactants accumulate at the air-sea interface, forming microlayer films, slicks, and foam patches. The resulting enhanced viscoelasticity of the interface alters the small-scale wave spectrum and near-surface turbulence. These changes alter the surface thermal boundary layer and ``skin'' temperature, making infrared thermal imagery ideal for detecting/mapping/studying ocean slicks. Slicks are found under a range of conditions and can result from physical straining of the sea surface (e.g. internal waves) as well as from local biological processes (e.g. plankton blooms). Airborne datasets that combine simultaneous airborne infrared and visible wavelength hyperspectral remote sensing data are now available and provide new opportunities to investigate the physical and biological processes that result in ocean slicks. In addition to the multiple sensors, these datasets are at spatial and time scales much smaller than possible with available satellite remote sensors. This enables the study of a much broader range of phenomena. In particular we investigate the relationship between surface accumulations of vegetative material, ocean slicks and surface temperature changes. We also investigate the relationship between the presence of slicks and water column chromophoric dissolved organic matter (CDOM).

  3. Airborne infrared hyperspectral imager for intelligence, surveillance and reconnaissance applications

    NASA Astrophysics Data System (ADS)

    Lagueux, Philippe; Puckrin, Eldon; Turcotte, Caroline S.; Gagnon, Marc-André; Bastedo, John; Farley, Vincent; Chamberland, Martin

    2012-09-01

    Persistent surveillance and collection of airborne intelligence, surveillance and reconnaissance information is critical in today's warfare against terrorism. High resolution imagery in visible and infrared bands provides valuable detection capabilities based on target shapes and temperatures. However, the spectral resolution provided by a hyperspectral imager adds a spectral dimension to the measurements, leading to additional tools for detection and identification of targets, based on their spectral signature. The Telops Hyper-Cam sensor is an interferometer-based imaging system that enables the spatial and spectral analysis of targets using a single sensor. It is based on the Fourier-transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. It provides datacubes of up to 320×256 pixels at spectral resolutions as fine as 0.25 cm-1. The LWIR version covers the 8.0 to 11.8 μm spectral range. The Hyper-Cam has been recently used for the first time in two compact airborne platforms: a bellymounted gyro-stabilized platform and a gyro-stabilized gimbal ball. Both platforms are described in this paper, and successful results of high-altitude detection and identification of targets, including industrial plumes, and chemical spills are presented.

  4. Airborne infrared hyperspectral imager for intelligence, surveillance, and reconnaissance applications

    NASA Astrophysics Data System (ADS)

    Puckrin, Eldon; Turcotte, Caroline S.; Gagnon, Marc-André; Bastedo, John; Farley, Vincent; Chamberland, Martin

    2012-06-01

    Persistent surveillance and collection of airborne intelligence, surveillance and reconnaissance information is critical in today's warfare against terrorism. High resolution imagery in visible and infrared bands provides valuable detection capabilities based on target shapes and temperatures. However, the spectral resolution provided by a hyperspectral imager adds a spectral dimension to the measurements, leading to additional tools for detection and identification of targets, based on their spectral signature. The Telops Hyper-Cam sensor is an interferometer-based imaging system that enables the spatial and spectral analysis of targets using a single sensor. It is based on the Fourier-transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. It provides datacubes of up to 320×256 pixels at spectral resolutions as fine as 0.25 cm-1. The LWIR version covers the 8.0 to 11.8 μm spectral range. The Hyper-Cam has been recently used for the first time in two compact airborne platforms: a belly-mounted gyro-stabilized platform and a gyro-stabilized gimbal ball. Both platforms are described in this paper, and successful results of high-altitude detection and identification of targets, including industrial plumes, and chemical spills are presented.

  5. Infrared and visible images fusion based on RPCA and NSCT

    NASA Astrophysics Data System (ADS)

    Fu, Zhizhong; Wang, Xue; Xu, Jin; Zhou, Ning; Zhao, Yufei

    2016-07-01

    Current infrared and visible images fusion algorithms cannot efficiently extract the object information in the infrared image while retaining the background information in visible image. To address this issue, we propose a new infrared and visible image fusion algorithm by taking advantage of robust principal component analysis (RPCA) and non-subsampled Contourlet transform (NSCT). Firstly, RPCA decomposition is performed on the infrared and visible images respectively to obtain their corresponding sparse matrixes, which can well represent the sparse feature of images. Secondly, the infrared and visible images are decomposed into low frequency sub-band and high-frequency sub-band coefficients by using NSCT. Subsequently, the sparse matrixes are used to guide the fusion rule of low frequency sub-band coefficients and high frequency sub-band coefficients. Experimental results demonstrate that our fusion algorithm can highlight the infrared objects as well as retain the background information in visible image.

  6. Nanoantennas for visible and infrared radiation.

    PubMed

    Biagioni, Paolo; Huang, Jer-Shing; Hecht, Bert

    2012-02-01

    Nanoantennas for visible and infrared radiation can strongly enhance the interaction of light with nanoscale matter by their ability to efficiently link propagating and spatially localized optical fields. This ability unlocks an enormous potential for applications ranging from nanoscale optical microscopy and spectroscopy over solar energy conversion, integrated optical nanocircuitry, opto-electronics and density-of-states engineering to ultra-sensing as well as enhancement of optical nonlinearities. Here we review the current understanding of metallic optical antennas based on the background of both well-developed radiowave antenna engineering and plasmonics. In particular, we discuss the role of plasmonic resonances on the performance of nanoantennas and address the influence of geometrical parameters imposed by nanofabrication. Finally, we give a brief account of the current status of the field and the major established and emerging lines of investigation in this vivid area of research.

  7. Hyperspectral low altitude flashtube illuminator system for visible and near-infrared remote sensing

    SciTech Connect

    Kalshoven, J.E.

    1996-10-01

    A high energy flashtube is integrated with an airborne spectrometer system for hyperspectral remote sensing of the Earth`s surface. The system, called AVIS (Airborne Vegetation Index Sensor) and currently mounted on a NASA helicopter, is flown at a nominal altitude of 500 feet (150 m). The flashtube is a two joule Xenon lamp pulsed at a 2 Hz rate. The transmitting optics give a 15 x 35 mrad beam output. The receiver is a grating spectrometer with a 512 element CCD linear array which provides a high resolution output of the backscattered visible and infrared spectrum. The system is currently used for forest canopy studies. 5 figs., 2 tabs.

  8. Visible-Near Infrared Imaging Spectrometer Data of Explosion Craters

    NASA Technical Reports Server (NTRS)

    Farr, T. G.

    2005-01-01

    In a continuing study to capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained new high resolution visible-near infrared images of several explosion craters at the Nevada Test Site. We used the Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) to obtain images in 224 spectral bands from 0.4-2.5 microns [1]. The main craters that were imaged were Sedan, Scooter, Schooner, Buggy, and Danny Boy [2]. The 390 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of the detonation of a 104 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a "simple" crater [2]. Sedan was formed in alluvium of mixed lithology [3] and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also imaged by AVIRIS. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m, Fig. 1) craters were also important targets for AVIRIS as they were excavated in hard welded tuff and basaltic andesite, respectively [3, 4]. This variation in targets will allow the study of ejecta patterns, compositional modifications due to the explosions, and the role of craters as subsurface probes.

  9. Visible/infrared radiometric calibration station

    SciTech Connect

    Byrd, D.A.; Maier, W.B. II; Bender, S.C.; Holland, R.F.; Michaud, F.D.; Luettgen, A.L.; Christensen, R.W.; O`Brian, T.R.

    1994-07-01

    We have begun construction of a visible/infrared radiometric calibration station that will allow for absolute calibration of optical and IR remote sensing instruments with clear apertures less than 16 inches in diameter in a vacuum environment. The calibration station broadband sources will be calibrated at the National Institute of Standards and Technology (NIST) and allow for traceable absolute radiometric calibration to within {plus_minus}3% in the visible and near IR (0.4--2.5 {mu}m), and less than {plus_minus}1% in the infrared, up to 12 {mu}m. Capabilities for placing diffraction limited images or for sensor full-field flooding will exist. The facility will also include the calibration of polarization and spectral effects, spatial resolution, field of view performance, and wavefront characterization. The configuration of the vacuum calibration station consists of an off-axis 21 inch, f/3.2, parabolic collimator with a scanning fold flat in collimated space. The sources are placed, via mechanisms to be described, at the focal plane of the off-axis parabola. Vacuum system pressure will be in the 10{sup {minus}6} Torr range. The broadband white-light source is a custom design by LANL with guidance from Labsphere Inc. The continuous operating radiance of the integrating sphere will be from 0.0--0.006 W/cm{sup 2}/Sr/{mu}m (upper level quoted for {approximately}500 nm wavelength). The blackbody source is also custom designed at LANL with guidance from NIST. The blackbody temperature will be controllable between 250--350{degrees}K. Both of the above sources have 4.1 inch apertures with estimated radiometric instability at less than 1%. The designs of each of these units will be described. The monochromator and interferometer light sources are outside the vacuum, but all optical relay and beam shaping optics are enclosed within the vacuum calibration station. These sources are described, as well as the methodology for alignment and characterization.

  10. On the visibility of airborne volcanic ash and mineral dust

    NASA Astrophysics Data System (ADS)

    Weinzierl, B.; Sauer, D. N.; Minikin, A.; Reitebuch, O.; Dahlkötter, F.; Mayer, B. C.; Emde, C.; Tegen, I.; Gasteiger, J.; Petzold, A.; Veira, A.; Kueppers, U.; Schumann, U.

    2012-12-01

    airborne aerosol layer and the background, the illumination, the particle size distribution and mass concentration, the wavelength-dependent light scattering and absorption by the aerosol layer, the human perception, etc. In addition, the optical depth along the line of sight through an aerosol layer is more important than just the (vertical) optical depth, which is measured, for example, by sun photometers or satellites. The results of our study are in particular interesting for the question on the visibility of volcanic ash. Our analyses of "visible ash" demonstrate that under clear sky conditions volcanic ash is visible already at concentrations far below what is currently considered as the upper limit for safe operation of an aircraft engine (2 mg m-3). The presence of a grayish-brown layer in the atmosphere does not unambiguously indicate the presence of volcanic ash. An uninformed observer is unlikely to identify an aged volcanic ash layer in his field of view without further information. The presence of clouds would make it even more complicated to visually detect volcanic ash. In regions with high background aerosol loading in the atmosphere from natural or anthropogenic influences, such as seen in large parts of Asia, the visual detection of volcanic ash as an additional contaminant will be substantially more difficult.

  11. Visible-Infrared Hyperspectral Image Projector

    NASA Technical Reports Server (NTRS)

    Bolcar, Matthew

    2013-01-01

    The VisIR HIP generates spatially-spectrally complex scenes. The generated scenes simulate real-world targets viewed by various remote sensing instruments. The VisIR HIP consists of two subsystems: a spectral engine and a spatial engine. The spectral engine generates spectrally complex uniform illumination that spans the wavelength range between 380 nm and 1,600 nm. The spatial engine generates two-dimensional gray-scale scenes. When combined, the two engines are capable of producing two-dimensional scenes with a unique spectrum at each pixel. The VisIR HIP can be used to calibrate any spectrally sensitive remote-sensing instrument. Tests were conducted on the Wide-field Imaging Interferometer Testbed at NASA s Goddard Space Flight Center. The device is a variation of the calibrated hyperspectral image projector developed by the National Institute of Standards and Technology in Gaithersburg, MD. It uses Gooch & Housego Visible and Infrared OL490 Agile Light Sources to generate arbitrary spectra. The two light sources are coupled to a digital light processing (DLP(TradeMark)) digital mirror device (DMD) that serves as the spatial engine. Scenes are displayed on the DMD synchronously with desired spectrum. Scene/spectrum combinations are displayed in rapid succession, over time intervals that are short compared to the integration time of the system under test.

  12. Airborne measurements in the infrared using FTIR-based imaging hyperspectral sensors

    NASA Astrophysics Data System (ADS)

    Puckrin, E.; Turcotte, C. S.; Lahaie, P.; Dubé, D.; Farley, V.; Lagueux, P.; Marcotte, F.; Chamberland, M.

    2009-05-01

    Hyperspectral ground mapping is being used in an ever-increasing extent for numerous applications in the military, geology and environmental fields. The different regions of the electromagnetic spectrum help produce information of differing nature. The visible, near-infrared and short-wave infrared radiation (400 nm to 2.5 μm) has been mostly used to analyze reflected solar light, while the mid-wave (3 to 5 μm) and long-wave (8 to 12 μm or thermal) infrared senses the self-emission of molecules directly, enabling the acquisition of data during night time. Push-broom dispersive sensors have been typically used for airborne hyperspectral mapping. However, extending the spectral range towards the mid-wave and long-wave infrared brings performance limitations due to the self emission of the sensor itself. The Fourier-transform spectrometer technology has been extensively used in the infrared spectral range due to its high transmittance as well as throughput and multiplex advantages, thereby reducing the sensor self-emission problem. Telops has developed the Hyper-Cam, a rugged and compact infrared hyperspectral imager. The Hyper-Cam is based on the Fourier-transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. It provides passive signature measurement capability, with up to 320x256 pixels at spectral resolutions of up to 0.25 cm-1. The Hyper-Cam has been used on the ground in several field campaigns, including the demonstration of standoff chemical agent detection. More recently, the Hyper-Cam has been integrated into an airplane to provide airborne measurement capabilities. A special pointing module was designed to compensate for airplane attitude and forward motion. To our knowledge, the Hyper-Cam is the first commercial airborne hyperspectral imaging sensor based on Fourier-transform infrared technology. The first airborne measurements and some preliminary performance criteria for the Hyper-Cam are presented in

  13. Airborne measurements in the infrared using FTIR-based imaging hyperspectral sensors

    NASA Astrophysics Data System (ADS)

    Puckrin, E.; Turcotte, C. S.; Lahaie, P.; Dubé, D.; Lagueux, P.; Farley, V.; Marcotte, F.; Chamberland, M.

    2009-09-01

    Hyperspectral ground mapping is being used in an ever-increasing extent for numerous applications in the military, geology and environmental fields. The different regions of the electromagnetic spectrum help produce information of differing nature. The visible, near-infrared and short-wave infrared radiation (400 nm to 2.5 μm) has been mostly used to analyze reflected solar light, while the mid-wave (3 to 5 μm) and long-wave (8 to 12 μm or thermal) infrared senses the self-emission of molecules directly, enabling the acquisition of data during night time. Push-broom dispersive sensors have been typically used for airborne hyperspectral mapping. However, extending the spectral range towards the mid-wave and long-wave infrared brings performance limitations due to the self emission of the sensor itself. The Fourier-transform spectrometer technology has been extensively used in the infrared spectral range due to its high transmittance as well as throughput and multiplex advantages, thereby reducing the sensor self-emission problem. Telops has developed the Hyper-Cam, a rugged and compact infrared hyperspectral imager. The Hyper-Cam is based on the Fourier-transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. It provides passive signature measurement capability, with up to 320x256 pixels at spectral resolutions of up to 0.25 cm-1. The Hyper-Cam has been used on the ground in several field campaigns, including the demonstration of standoff chemical agent detection. More recently, the Hyper-Cam has been integrated into an airplane to provide airborne measurement capabilities. A special pointing module was designed to compensate for airplane attitude and forward motion. To our knowledge, the Hyper-Cam is the first commercial airborne hyperspectral imaging sensor based on Fourier-transform infrared technology. The first airborne measurements and some preliminary performance criteria for the Hyper-Cam are presented in

  14. Airborne infrared mineral mapping survey of Marysvale, Utah

    NASA Technical Reports Server (NTRS)

    Collins, W.; Chang, S. H.

    1982-01-01

    Infrared spectroradiometer survey results from flights over the Marysvale, Utah district show that hydrothermal alteration mineralogy can be mapped using very rapid and effective airborne techniques. The system detects alteration mineral absorption band intensities in the infrared spectral region with high sensitivity. The higher resolution spectral features and high spectral differences characteristic of the various clay and carbonate minerals are also readily identified by the instrument allowing the mineralogy to be mapped as well as the mineralization intensity.

  15. An Algorithm to Atmospherically Correct Visible and Thermal Airborne Imagery

    NASA Technical Reports Server (NTRS)

    Rickman, Doug L.; Luvall, Jeffrey C.; Schiller, Stephen; Arnold, James E. (Technical Monitor)

    2000-01-01

    The program Watts implements a system of physically based models developed by the authors, described elsewhere, for the removal of atmospheric effects in multispectral imagery. The band range we treat covers the visible, near IR and the thermal IR. Input to the program begins with atmospheric pal red models specifying transmittance and path radiance. The system also requires the sensor's spectral response curves and knowledge of the scanner's geometric definition. Radiometric characterization of the sensor during data acquisition is also necessary. While the authors contend that active calibration is critical for serious analytical efforts, we recognize that most remote sensing systems, either airborne or space borne, do not as yet attain that minimal level of sophistication. Therefore, Watts will also use semi-active calibration where necessary and available. All of the input is then reduced to common terms, in terms of the physical units. From this it Is then practical to convert raw sensor readings into geophysically meaningful units. There are a large number of intricate details necessary to bring an algorithm or this type to fruition and to even use the program. Further, at this stage of development the authors are uncertain as to the optimal presentation or minimal analytical techniques which users of this type of software must have. Therefore, Watts permits users to break out and analyze the input in various ways. Implemented in REXX under OS/2 the program is designed with attention to the probability that it will be ported to other systems and other languages. Further, as it is in REXX, it is relatively simple for anyone that is literate in any computer language to open the code and modify to meet their needs. The authors have employed Watts in their research addressing precision agriculture and urban heat island.

  16. Tunable Infrared Laser Instruments for Airborne Atmospheric Studies

    NASA Technical Reports Server (NTRS)

    Fried, A.; Diskin, G.; Weibring, P.; Richter, D.; Walega, J. G.; Sachse, G.; Slate, T.; Rana, M.; Podolske, J.

    2008-01-01

    Tunable infrared laser-based instruments on airborne platforms have provided invaluable contributions to atmospheric studies over the past several decades. This paper presents an overview of some recent studies and developments using this approach that were presented at the 2007 Field Laser Applications in Industry and Research (FLAIR, http://www.inoa.it/flair/) conference in Florence, Italy. The present overview only covers select in situ absorption-based instruments that were presented in the airborne session at this conference. In no case are comprehensive details presented. These details can be found in the numerous references given. Additional approaches based upon cavity-enhanced and photoacoustic measurements, which are also making invaluable contributions in airborne atmospheric studies, are not discussed in this brief overview.

  17. Development and evaluation of technologies for testing visible and infrared imaging sensors

    NASA Astrophysics Data System (ADS)

    Lowry, H. S.; Steely, S. L.; Phillips, W. J.; Nicholson, R. A.

    2014-05-01

    Ground testing of space and airborne imaging sensor systems is supported by visible-to-long wave infrared (LWIR) imaging sensor calibration and characterization, as well as hardware-in-the-loop (HWIL) simulation with high-fidelity complex scene projection to validate sensor mission performance. To accomplish this successfully, there must be the development and evaluation of technologies that are used in space simulation chambers for such testing, including emitter-array cryotesting, silicon-carbide mirror cryotesting, and flood-source development. This paper provides an overview of the efforts being investigated and implemented at Arnold Engineering Development Complex (AEDC).

  18. Comparative study on atmospheric correction methods of visible and near-infrared hyperspectral image

    NASA Astrophysics Data System (ADS)

    He, Qian; Wu, Jingli; Wang, Guangping; Liu, Chang; Tao, Tao

    2015-03-01

    Currently, common atmospheric correction methods usually based on the statistical information of image itself for relative reflectance calculation, or make use of the radiative transfer model and meteorological parameters for accurate calculations. In order to compare the advantages and disadvantages of these methods, we carried out some atmospheric correction experiments based on AVIRIS Airborne Visible and Near-Infrared hyperspectral data. It proved that, the statistical method is simple and convenient, but not wide adaptability, that can only get the relative reflectance; while the radiative transfer model method is very complex and require the support of auxiliary information, but it can get the precise absolute reflectance of surface features.

  19. Airborne infrared-hyperspectral mapping for detection of gaseous and solid targets

    NASA Astrophysics Data System (ADS)

    Puckrin, E.; Turcotte, C. S.; Lahaie, P.; Dubé, D.; Farley, V.; Lagueux, P.; Marcotte, F.; Chamberland, M.

    2010-04-01

    Airborne hyperspectral ground mapping is being used in an ever-increasing extent for numerous applications in the military, geology and environmental fields. The different regions of the electromagnetic spectrum help produce information of differing nature. The visible, near-infrared and short-wave infrared radiation (400 nm to 2.5 μm) has been mostly used to analyze reflected solar light, while the mid-wave (3 to 5 μm) and long-wave (8 to 12 μm or thermal) infrared senses the self-emission of molecules directly, enabling the acquisition of data during night time. The Telops Hyper-Cam is a rugged and compact infrared hyperspectral imager based on the Fourier-transform technology. It has been used on the ground in several field campaigns, including the demonstration of standoff chemical agent detection. More recently, the Hyper-Cam has been integrated into an airplane to provide airborne measurement capabilities. The technology offers fine spectral resolution (up to 0.25 cm-1) and high accuracy radiometric calibration (better than 1 degree Celsius). Furthermore, the spectral resolution, spatial resolution, swath width, integration time and sensitivity are all flexible parameters that can be selected and optimized to best address the specific objectives of each mission. The system performance and a few measurements have been presented in previous publications. This paper focuses on analyzing additional measurements in which detection of fertilizer and Freon gas has been demonstrated.

  20. Physics for the Correction of a Calibrated Airborne Scanner, Visible to Thermal Bands

    NASA Technical Reports Server (NTRS)

    Rickman, Doug L.; Schiller, Stephen; Luvall, Jeffrey C.; Arnold, James E. (Technical Monitor)

    2000-01-01

    To use remote sensing modalities in a reproducible manner it is essential that extraneous phenomena be removed from the signal. For those interested in the surface of the Earth, airborne and satellite systems, which are sensitive in wavelengths ranging from the visible to the infrared are significantly degraded by the atmosphere. The authors have developed a series of mathematical models to describe and correct the degradation. The models are based directly on the physics of the systems and are computationally tractable. Modeling of the atmosphere is done using public domain code, loaded with data and configured using information form systems developed by Schiller and Luvall. The results of this are then integrated with a physical model of the sensor to permit reduction of data to geophysically meaningful units. The components of the overall modeling, the logic of the components, and the limitations of the approach are discussed. The authors are employing there technology on applications ranging from measurements of urban heat islands to precision agriculture.

  1. An Airborne Infrared Spectrometer for Solar Eclipse Observations

    NASA Astrophysics Data System (ADS)

    Samra, Jenna; DeLuca, Edward E.; Golub, Leon; Cheimets, Peter; Philip, Judge

    2016-05-01

    The airborne infrared spectrometer (AIR-Spec) is an innovative solar spectrometer that will observe the 2017 solar eclipse from the NSF/NCAR High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER). AIR-Spec will image five infrared coronal emission lines to determine whether they may be useful probes of coronal magnetism.The solar magnetic field provides the free energy that controls coronal heating, structure, and dynamics. Energy stored in coronal magnetic fields is released in flares and coronal mass ejections and ultimately drives space weather. Therefore, direct coronal field measurements have significant potential to enhance understanding of coronal dynamics and improve solar forecasting models. Of particular interest are observations of field lines in the transitional region between closed and open flux systems, providing important information on the origin of the slow solar wind.While current instruments routinely observe only the photospheric and chromospheric magnetic fields, AIR-Spec will take a step toward the direct observation of coronal fields by measuring plasma emission in the infrared at high spatial and spectral resolution. During the total solar eclipse of 2017, AIR-Spec will observe five magnetically sensitive coronal emission lines between 1.4 and 4 µm from the HIAPER Gulfstream V at an altitude above 14.9 km. The instrument will measure emission line intensity, width, and Doppler shift, map the spatial distribution of infrared emitting plasma, and search for waves in the emission line velocities.AIR-Spec consists of an optical system (feed telescope, grating spectrometer, and infrared detector) and an image stabilization system, which uses a fast steering mirror to correct the line-of-sight for platform perturbations. To ensure that the instrument meets its research goals, both systems are undergoing extensive performance modeling and testing. These results are shown with reference to the science requirements.

  2. Chemical detection using the airborne thermal infrared imaging spectrometer (TIRIS)

    SciTech Connect

    Gat, N.; Subramanian, S.; Sheffield, M.; Erives, H.; Barhen, J.

    1997-04-01

    A methodology is described for an airborne, downlooking, longwave infrared imaging spectrometer based technique for the detection and tracking of plumes of toxic gases. Plumes can be observed in emission or absorption, depending on the thermal contrast between the vapor and the background terrain. While the sensor is currently undergoing laboratory calibration and characterization, a radiative exchange phenomenology model has been developed to predict sensor response and to facilitate the sensor design. An inverse problem model has also been developed to obtain plume parameters based on sensor measurements. These models, the sensors, and ongoing activities are described.

  3. Airborne laser systems for atmospheric sounding in the near infrared

    NASA Astrophysics Data System (ADS)

    Sabatini, Roberto; Richardson, Mark A.; Jia, Huamin; Zammit-Mangion, David

    2012-06-01

    This paper presents new techniques for atmospheric sounding using Near Infrared (NIR) laser sources, direct detection electro-optics and passive infrared imaging systems. These techniques allow a direct determination of atmospheric extinction and, through the adoption of suitable inversion algorithms, the indirect measurement of some important natural and man-made atmospheric constituents, including Carbon Dioxide (CO2). The proposed techniques are suitable for remote sensing missions performed by using aircraft, satellites, Unmanned Aerial Vehicles (UAV), parachute/gliding vehicles, Roving Surface Vehicles (RSV), or Permanent Surface Installations (PSI). The various techniques proposed offer relative advantages in different scenarios. All are based on measurements of the laser energy/power incident on target surfaces of known geometric and reflective characteristics, by means of infrared detectors and/or infrared cameras calibrated for radiance. Experimental results are presented relative to ground and flight trials performed with laser systems operating in the near infrared (NIR) at λ = 1064 nm and λ = 1550 nm. This includes ground tests performed with 10 Hz and 20 KHz PRF NIR laser systems in a variety of atmospheric conditions, and flight trials performed with a 10 Hz airborne NIR laser system installed on a TORNADO aircraft, flying up to altitudes of 22,000 ft above ground level. Future activities are planned to validate the atmospheric retrieval algorithms developed for CO2 column density measurements, with emphasis on aircraft related emissions at airports and other high air-traffic density environments.

  4. A femtosecond visible/visible and visible/mid-infrared transient absorption study of the light harvesting complex II.

    PubMed

    Stahl, Andreas D; Di Donato, Mariangela; van Stokkum, Ivo; van Grondelle, Rienk; Groot, Marie Louise

    2009-12-16

    Light harvesting complex II (LHCII) is the most abundant protein in the thylakoid membrane of higher plants and green algae. LHCII acts to collect solar radiation, transferring this energy mainly toward photosystem II, with a smaller amount going to photosystem I; it is then converted into a chemical, storable form. We performed time-resolved femtosecond visible pump/mid-infrared probe and visible pump/visible probe absorption difference spectroscopy on purified LHCII to gain insight into the energy transfer in this complex occurring in the femto-picosecond time regime. We find that information derived from mid-infrared spectra, together with structural and modeling information, provides a unique visualization of the flow of energy via the bottleneck pigment chlorophyll a604.

  5. A visible-infrared imaging spectrometer for planetary missions

    NASA Technical Reports Server (NTRS)

    McCord, Thomas (Principal Investigator); Voelker, Mark; Owensby, Pam; Warren, Cris; Mooradian, Greg

    1996-01-01

    This final report summarizes the design effort for the construction of a visible-infrared imaging spectrometer for planetary missions, funded by NASA under the Planetary Instrument Definition and Development Program. The goal was to design and develop a prototype brassboard pushbroom imaging spectrometer covering the 0.35 gm to 2.5 gm spectral region using a simplified optical layout that would minimize the size, mass and parts count of the instrument by using a single holographic grating to disperse and focus light from a single slit onto both the infrared and visible focal plane arrays. Design approaches are presented and analyzed, along with problems encountered and recommended solutions to those problems. In particular, a new type of grating, incorporating two sets of rulings and a filter in a layered structure, is presented for further development.

  6. Visible and Infrared Optical Design for the ITER Upper Ports

    SciTech Connect

    Lasnier, C; Seppala, L; Morris, K; Groth, M; Fenstermacher, M; Allen, S; Synakowski, E; Ortiz, J

    2007-03-01

    This document contains the results of an optical design scoping study of visible-light and infrared optics for the ITER upper ports, performed by LLNL under contract for the US ITER Project Office. ITER is an international collaboration to build a large fusion energy tokamak with a goal of demonstrating net fusion power for pulses much longer than the energy confinement time. At the time of this report, six of the ITER upper ports are planned to each to contain a camera system for recording visible and infrared light, as well as other diagnostics. the performance specifications for the temporal and spatial resolution of this system are shown in the Section II, Functional Specifications. They acknowledge a debt to Y. Corre and co-authors of the CEA Cadarache report ''ITER wide-angle viewing and thermographic and visible system''. Several of the concepts used in this design are derived from that CEA report. The infrared spatial resolution for optics of this design is diffraction-limited by the size of the entrance aperture, at lower resolution than listed in the ITER diagnostic specifications. The size of the entrance aperture is a trade-off between spatial resolution, optics size in the port, and the location of relay optics. The signal-to-noise ratio allows operation at the specified time resolutions.

  7. Thermal Infrared Spectral Imager for Airborne Science Applications

    NASA Technical Reports Server (NTRS)

    Johnson, William R.; Hook, Simon J.; Mouroulis, Pantazis; Wilson, Daniel W.; Gunapala, Sarath D.; Hill, Cory J.; Mumolo, Jason M.; Eng, Bjorn T.

    2009-01-01

    An airborne thermal hyperspectral imager is under development which utilizes the compact Dyson optical configuration and quantum well infrared photo detector (QWIP) focal plane array. The Dyson configuration uses a single monolithic prism-like grating design which allows for a high throughput instrument (F/1.6) with minimal ghosting, stray-light and large swath width. The configuration has the potential to be the optimal imaging spectroscopy solution for lighter-than-air (LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The planned instrument specifications are discussed as well as design trade-offs. Calibration testing results (noise equivalent temperature difference, spectral linearity and spectral bandwidth) and laboratory emissivity plots from samples are shown using an operational testbed unit which has similar specifications as the final airborne system. Field testing of the testbed unit was performed to acquire plots of apparent emissivity for various known standard minerals (such as quartz). A comparison is made using data from the ASTER spectral library.

  8. Compositional and textural information from the dual inversion of visible, near and thermal infrared remotely sensed data

    NASA Technical Reports Server (NTRS)

    Brackett, Robert A.; Arvidson, Raymond E.

    1993-01-01

    A technique is presented that allows extraction of compositional and textural information from visible, near and thermal infrared remotely sensed data. Using a library of both emissivity and reflectance spectra, endmember abundances and endmember thermal inertias are extracted from AVIRIS (Airborne Visible and Infrared Imaging Spectrometer) and TIMS (Thermal Infrared Mapping Spectrometer) data over Lunar Crater Volcanic Field, Nevada, using a dual inversion. The inversion technique is motivated by upcoming Mars Observer data and the need for separation of composition and texture parameters from sub pixel mixtures of bedrock and dust. The model employed offers the opportunity to extract compositional and textural information for a variety of endmembers within a given pixel. Geologic inferences concerning grain size, abundance, and source of endmembers can be made directly from the inverted data. These parameters are of direct relevance to Mars exploration, both for Mars Observer and for follow-on missions.

  9. The new airborne Thermal Infrared Multispectral Scanner (TIMS)

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.

    1983-01-01

    A new airborne Thermal Infrared Multispectral Scanner (TIMS) with six bands between 8 and 12 microns is briefly characterized, and some results of remote sensing experiments are reported. The instrument has an instantaneous field of view of 2.5 milliradians, a total field of view of 80 deg, and a NE Delta T of approximately 0.1-0.3 C depending on the band. In the TIMS image of Death Valley, silica-rich rocks were easily separable from the nonsilicates. The Eureka Quartzite stood out in sharp contrast to other Ordovician and Cambrian metasediments, and Tertiary volcanic rocks were easily separable from both. Also distinguishable were various units in the fan gravels.

  10. Application of combined Landsat thematic mapper and airborne thermal infrared multispectral scanner data to lithologic mapping in Nevada

    USGS Publications Warehouse

    Podwysocki, M.H.; Ehmann, W.J.; Brickey, D.W.

    1987-01-01

    Future Landsat satellites are to include the Thematic Mapper (TM) and also may incorporate additional multispectral scanners. One such scanner being considered for geologic and other applications is a four-channel thermal-infrared multispectral scanner having 60-m spatial resolution. This paper discusses the results of studies using combined Landsat TM and airborne Thermal Infrared Multispectral Scanner (TIMS) digital data for lithologic discrimination, identification, and geologic mapping in two areas within the Basin and Range province of Nevada. Field and laboratory reflectance spectra in the visible and reflective-infrared and laboratory spectra in the thermal-infrared parts of the spectrum were used to verify distinctions made between rock types in the image data sets.

  11. Visible/near-infrared spectra of experimentally shocked plagioclase feldspars

    USGS Publications Warehouse

    Johnson, J. R.; Horz, F.

    2003-01-01

    High shock pressures cause structural changes in plagioclase feldspars such as mechanical fracturing and disaggregation of the crystal lattice at submicron scales, the formation of diaplectic glass (maskelynite), and genuine melting. Past studies of visible/ near-infrared spectra of shocked feldspars demonstrated few spectral variations with pressure except for a decrease in the depth of the absorption feature near 1250-1300 nm and an overall decrease in reflectance. New visible/near-infrared spectra (400-2500 nm) of experimentally shocked (17-56 GPa) albite- and anorthite-rich rock powders demonstrate similar trends, including the loss of minor hydrated mineral bands near 1410, 1930, 2250, and 2350 nm. However, the most interesting new observations are increases in reflectance at intermediate pressures, followed by subsequent decreases in reflectance at higher pressures. The amount of internal scattering and overall sample reflectance is controlled by the relative proportions of micro-fractures, submicron grains, diaplectic glass, and melts formed during shock metamorphism. We interpret the observed reflectance increases at intermediate pressures to result from progressively larger proportions of submicron feldspar grains and diaplectic glass. The ensuing decreases in reflectance occur after diaplectic glass formation is complete and the proportion of genuine melt inclusions increases. The pressure regimes over which these reflectance variations occur differ between albite and anorthite, consistent with thermal infrared spectra of these samples and previous studies of shocked feldspars. These types of spectral variations associated with different peak shock pressures should be considered during interpretation and modeling of visible/near-infrared remotely sensed spectra of planetary and asteroidal surfaces.

  12. Roof heat loss detection using airborne thermal infrared imagery

    NASA Astrophysics Data System (ADS)

    Kern, K.; Bauer, C.; Sulzer, W.

    2012-12-01

    As part of the Austrian and European attempt to reduce energy consumption and greenhouse gas emissions, thermal rehabilitation and the improvement of the energy efficiency of buildings became an important topic in research as well as in building construction and refurbishment. Today, in-situ thermal infrared measurements are routinely used to determine energy loss through the building envelope. However, in-situ thermal surveys are expensive and time consuming, and in many cases the detection of the amount and location of waste heat leaving building through roofs is not possible with ground-based observations. For some years now, a new generation of high-resolution thermal infrared sensors makes it possible to survey heat-loss through roofs at a high level of detail and accuracy. However, to date, comparable studies have mainly been conducted on buildings with uniform roof covering and provided two-dimensional, qualitative information. This pilot study aims to survey the heat-loss through roofs of the buildings of the University of Graz (Austria) campus by using high-resolution airborne thermal infrared imagery (TABI 1800 - Thermal Airborne Broadband imager). TABI-1800 acquires data in a spectral range from 3.7 - 4.8 micron, a thermal resolution of 0.05 °C and a spatial resolution of 0.6 m. The remote sensing data is calibrated to different roof coverings (e.g. clay shingle, asphalt shingle, tin roof, glass) and combined with a roof surface model to determine the amount of waste heat leaving the building and to identify hot spots. The additional integration of information about the conditions underneath the roofs into the study allows a more detailed analysis of the upward heat flux and is a significant improvement of existing methods. The resulting data set provides useful information to the university facility service for infrastructure maintenance, especially in terms of attic and roof insulation improvements. Beyond that, the project is supposed to raise public

  13. Ultraviolet-visible-near infrared spectra of 50 samples

    SciTech Connect

    Taylor, B.

    1988-08-30

    Under the subject contract, Unidynamics/Phoenix recorded the ultraviolet-visible-near infrared spectra of 50 samples supplied by LANL. A Varian Cary 2300 series spectrophotometer produced the spectral data. The spectrophotometer was interfaced to a Varian D5-15 Data Station, and hard copies of data were made. Baseline corrections throughout the wavelength range were established using Halon as a reference material. Corrected measurements were automatically made by the system on every sample. Two types of sample holders were tried. Before collecting data on the LANL samples, identical samples of PETN were examined using both holders.

  14. Optimal structural design of the Airborne Infrared Imager

    NASA Astrophysics Data System (ADS)

    Doyle, Keith B.; Cerrati, Vincent J.; Forman, Steven E.; Sultana, John A.

    1995-09-01

    The airborne infrared imager (AIRI) is a dual-band IR sensor designed to study air defense issues while wing mounted in a pod. The sensor consists of an optical bench attached to a two- axis inertially stabilized gimbal structure in elevation and azimuth. The gimbal assembly operates within an 18-inch diameter globe while meeting strict pointing and tracking requirements. Design conditions for the assembly include operational and nonoperational inertial, thermal, and dynamic loads. Primary design efforts centered on limiting the line-of- sight jitter of the optical system to 50 (mu) rad under the operating environment. An MSC/NASTRAN finite element model was developed for structural response predictions and correlated to experimental data. Design changes were aided by MSC/NASTRAN's optimization routine with the goal of maximizing the fundamental frequency of the gimbal assembly. The final structural design resultsed in a first natural frequency of 79 Hz using a titanium azimuthal gimbal, a stainless steel elevation gimbal, and an aluminum optical bench which met the design and performance requirements.

  15. Infrared heterodyne radiometer for airborne atmospheric transmittance measurements

    NASA Technical Reports Server (NTRS)

    Wolczok, J. M.; Lange, R. A.; Dinardo, A. J.

    1980-01-01

    An infrared heterodyne radiometer (IHR) was used to measure atmospheric transmittance at selected hydrogen fluoride (2.7 micrometer) and deuterium fluoride (3.8 micrometer) laser transitions. The IHR was installed aboard a KC-135 aircraft for an airborne atmospheric measurements program that used the sun as a backlighting source for the transmission measurements. The critical components are: a wideband indium antimonide (1nSb) photomixer, a CW HF/DF laser L0, a radiometric processor, and a 1900 K blackbody reference source. The measured heterodyne receiver sensitivity (NEP) is 1.3 x 10 to the -19th power W/Hz, which yields a calculated IHR temperature resolution accuracy of delta I sub S/-3 sub S = 0.005 for a source temperature of 1000 K and a total transmittance of 0.5. Measured atmospheric transmittance at several wavelengths and aircraft altitudes from 9.14 km (30,000 ft) to 13.72 km (45,000 ft) were obtained during the measurements program and have been compared with values predicted by the AFGL Atmospheric Line Parameter Compilation.

  16. Optical motion detector detecting visible and near infrared light

    NASA Astrophysics Data System (ADS)

    Everett, Hobart R., Jr.

    1990-02-01

    An optical motion detector detects changes in scene lighting indicative of motion and is also capable of detecting surveillance by active night vision devices using near-infrared light. The detector includes two photodetectors which each provide data to a signal processing network. One photodetector is sensitive to visible light; the other to near-infrared light. Both signal processing networks are identical and include a sample-and-hold, a comparator network, and a pulse stretcher. The output of a photodetector is provided to the sample-and-hold and comparator network. The comparator network compares a voltage corresponding to the instantaneously detected ambient lighting scene with a voltage corresponding to a reference lighting scene. The pulse stretcher receives the output of the comparator network and in turn provides an output to a logical processor. The logical processor compares the outputs of both signal processing networks and provides an output indicating surveillance with near-infrared light. The logical processor also indicates any perturbations in intensities of incandescent and fluorescent light.

  17. Land surface temperature retrieved from airborne multispectral scanner mid-infrared and thermal-infrared data.

    PubMed

    Qian, Yong-Gang; Wang, Ning; Ma, Ling-Ling; Liu, Yao-Kai; Wu, Hua; Tang, Bo-Hui; Tang, Ling-Li; Li, Chuan-Rong

    2016-01-25

    Land surface temperature (LST) is one of the key parameters in the physics of land surface processes at local/global scales. In this paper, a LST retrieval method was proposed from airborne multispectral scanner data comparing one mid-infrared (MIR) channel and one thermal infrared (TIR) channel with the land surface emissivity given as a priori knowledge. To remove the influence of the direct solar radiance efficiently, a relationship between the direct solar radiance and water vapor content and the view zenith angle and solar zenith angle was established. Then, LST could be retrieved with a split-window algorithm from MIR/TIR data. Finally, the proposed algorithm was applied to the actual airborne flight data and validated with in situ measurements of land surface types in the Baotou site in China on 17 October 2014. The results demonstrate that the difference between the retrieved and in situ LST was less than 1.5 K. The bais, RMSE, and standard deviation of the retrieved LST were 0.156 K, 0.883 K, and 0.869 K, respectively, for samples. PMID:26832579

  18. Calibration of high resolution remote sensing instruments in the visible and near infrared

    NASA Astrophysics Data System (ADS)

    Schüller, L.; Fischer, J.; Armbruster, W.; Bartsch, B.

    1997-05-01

    Measurements of the reflected solar radiation with high spectral resolution airborne instruments are usually used to develop new remote sensing techniques. The observed spectral features in the signals provide the possibility to define useful band settings for future satellite instruments. A precise wavelength and radiometric calibration is a prerequisite for such tasks. In this paper, a calibration procedure for the airborne spectrometer OVID is presented. The Optical Visible and near Infrared Detector consists of two similar detector systems, (600 - 1100 nm = VIS and 900 - 1700 nm = NIR). The spectral resolution is ~1.7 nm for the VIS-system and ~6 nm for the IR-system. This instrument is applied for the retrieval of water vapour content, aerosol and cloud properties. Besides the spectral and intensity calibration, also corrections for the dark current signals and for defective pixels have been performed. An indirect verification of the calibration procedure by the comparison of OVID measurements in cloudy and cloud free atmospheres with radiative transfer simulations is discussed in this paper. The used radiation transfer model MOMO is based on the matrix operator method.

  19. Comparative influences of airborne pollutants and meteorological parameters on atmospheric visibility and turbidity

    NASA Astrophysics Data System (ADS)

    Wen, Chih-Chung; Yeh, Hui-Hsuan

    2010-06-01

    The purpose of this paper was to investigate how atmospheric air pollutants and meteorological conditions affect atmospheric visibility and turbidity. Meteorological parameter and anthropogenic air pollutant values were recorded during 2004 and 2005 at the Wuchi weather station and the Sha-lu environmental quality database station at the Taichung Harbor near the Taiwan Strait. Local weather conditions (temperature, relative humidity and solar radiation) and airborne pollutant (PM 10, SO 2, NO 2, CO and O 3) concentrations were used to analyze the relative effects of atmospheric air pollutants and meteorological conditions on atmospheric visibility and turbidity. Based on the analytic results, air pollutant concentrations significantly influence visibility and atmospheric turbidity. Wind speed is an important meteorological parameter that affects atmospheric turbidity parameters at the same atmospheric air pollutant concentrations throughout the periods of observation. At wind speeds of greater than 7 m/s, the turbidity factor β Vis is below 0.3 and visibility is greater than 6.5 km. Under very turbid conditions, β Vis > 0.4, the wind velocity is below 5 m/s, regardless of the atmospheric pollutant concentration. When visibility is ≥ 11 km, the PM 10 concentration is predicted to be below 150 μg/m 3 and the atmosphere is regarded as clear. Under very turbid conditions, the PM 10 concentration exceeds 250 μg/m 3.

  20. Visible and near infrared reflectances measured from laboratory ice clouds.

    PubMed

    Barkey, Brian; Liou, K N

    2008-05-01

    We present laboratory results of the 0.68 microm visible (VIS) and 1.617 microm near infrared (NIR) reflectances typically used for inferring optical depth and ice crystal size from satellite radiometers, from ice clouds generated in a temperature controlled column cloud chamber. Two types of ice crystals were produced in this experiment: small columns and dendrites with mean maximum dimensions of about 17 and 35 microm. Within experimental uncertainty, the measured reflectances from ice clouds at both wavelengths agree reasonably well with the theoretical results computed from the plane-parallel adding-doubling method for radiative transfer using the measured ice particle morphology. We demonstrate that laboratory scattering and reflectance data for thin ice clouds with optical depths less than 0.4 can be used for validation of the thin cirrus optical depth and ice crystal size that have been routinely retrieved from the satellite VIS-NIR two channel pair.

  1. Optimized microbolometers with higher sensitivity for visible and infrared imaging

    NASA Astrophysics Data System (ADS)

    Razansky, D.; Einziger, P. D.; Adam, D. R.; Tamir, T.

    2006-10-01

    Optimal absorption method for improving the sensitivity of bolometric detection is explored. We show that, in addition to its role in conventional conducting-film detection, the application of plasmon resonance absorption offers highly promising characteristics for efficient far-field thermal detection and imaging. These characteristics include good frequency sensitivity, intrinsic spatial (angle) selectivity without focusing lenses, wide tunability over both infrared and visible light domains, high responsivity and miniaturization capabilities. In this context, we examine the well-known surface plasmon resonance (SPR) regime, but also report on a new type of plasmon resonance excitation, the cavity plasmon resonance (CPR), which offers more flexibility over wide ranges of wavelengths, bandwidths, and device dimensions. Both CPR and SPR occur in metallic films, which are characterized by high thermal diffusivity essential for fast bolometric response.

  2. Optimized microbolometers with higher sensitivity for visible and infrared imaging.

    PubMed

    Razansky, D; Einziger, P D; Adam, D R; Tamir, T

    2006-10-30

    Optimal absorption method for improving the sensitivity of bolometric detection is explored. We show that, in addition to its role in conventional conducting-film detection, the application of plasmon resonance absorption offers highly promising characteristics for efficient far-field thermal detection and imaging. These characteristics include good frequency sensitivity, intrinsic spatial (angle) selectivity without focusing lenses, wide tunability over both infrared and visible light domains, high responsivity and miniaturization capabilities. In this context, we examine the well-known surface plasmon resonance (SPR) regime, but also report on a new type of plasmon resonance excitation, the cavity plasmon resonance (CPR), which offers more flexibility over wide ranges of wavelengths, bandwidths, and device dimensions. Both CPR and SPR occur in metallic films, which are characterized by high thermal diffusivity essential for fast bolometric response.

  3. Transmission spectra of teeth in the visible to near infrared

    NASA Astrophysics Data System (ADS)

    Herr, Steven L.; Harbour, John D.; Sherwood, Timothy S.; Wist, Abund O.

    1994-05-01

    Investigations of new transillumination techniques have created a need for detailed transmission studies of teeth and tissues. Recent results have shown that light imaging of extracted teeth can identify small (1 mm2 cross-section) caries in teeth by raster scanning using helium-neon laser light and a post collimated in-line detector. Preliminary frequency (wavelength) dependent transmission studies have been carried out from the visible to the near infrared spectral regions on the dentin of a slice of an extracted tooth 1.85 mm thick. These preliminary results show that in the region from 5,000 to 20,000 cm-1 the dentin of an extracted, healthy, human tooth has a transmission of between 2.5 and 5.5 percent, indicating that the total attenuation coefficient is between 16 and 19.5 cm-1.

  4. Visible and near infrared reflectances measured from laboratory ice clouds.

    PubMed

    Barkey, Brian; Liou, K N

    2008-05-01

    We present laboratory results of the 0.68 microm visible (VIS) and 1.617 microm near infrared (NIR) reflectances typically used for inferring optical depth and ice crystal size from satellite radiometers, from ice clouds generated in a temperature controlled column cloud chamber. Two types of ice crystals were produced in this experiment: small columns and dendrites with mean maximum dimensions of about 17 and 35 microm. Within experimental uncertainty, the measured reflectances from ice clouds at both wavelengths agree reasonably well with the theoretical results computed from the plane-parallel adding-doubling method for radiative transfer using the measured ice particle morphology. We demonstrate that laboratory scattering and reflectance data for thin ice clouds with optical depths less than 0.4 can be used for validation of the thin cirrus optical depth and ice crystal size that have been routinely retrieved from the satellite VIS-NIR two channel pair. PMID:18449323

  5. SKYWARD: the next generation airborne infrared search and track

    NASA Astrophysics Data System (ADS)

    Fortunato, L.; Colombi, G.; Ondini, A.; Quaranta, C.; Giunti, C.; Sozzi, B.; Balzarotti, G.

    2016-05-01

    Infrared Search and Track systems are an essential element of the modern and future combat aircrafts. Passive automatic search, detection and tracking functions, are key points for silent operations or jammed tactical scenarios. SKYWARD represents the latest evolution of IRST technology in which high quality electro-optical components, advanced algorithms, efficient hardware and software solutions are harmonically integrated to provide high-end affordable performances. Additionally, the reduction of critical opto-mechanical elements optimises weight and volume and increases the overall reliability. Multiple operative modes dedicated to different situations are available; many options can be selected among multiple or single target tracking, for surveillance or engagement, and imaging, for landing or navigation aid, assuring the maximum system flexibility. The high quality 2D-IR sensor is exploited by multiple parallel processing chains, based on linear and non-linear techniques, to extract the possible targets from background, in different conditions, with false alarm rate control. A widely tested track processor manages a large amount of candidate targets simultaneously and allows discriminating real targets from noise whilst operating with low target to background contrasts. The capability of providing reliable passive range estimation is an additional qualifying element of the system. Particular care has been dedicated to the detector non-uniformities, a possible limiting factor for distant targets detection, as well as to the design of the electro-optics for a harsh airborne environment. The system can be configured for LWIR or MWIR waveband according to the customer operational requirements. An embedded data recorder saves all the necessary images and data for mission debriefing, particularly useful during inflight system integration and tuning.

  6. Combing Visible and Infrared Spectral Tests for Dust Identification

    NASA Technical Reports Server (NTRS)

    Zhou, Yaping; Levy, Robert; Kleidman, Richard; Remer, Lorraine; Mattoo, Shana

    2016-01-01

    The MODIS Dark Target aerosol algorithm over Ocean (DT-O) uses spectral reflectance in the visible, near-IR and SWIR wavelengths to determine aerosol optical depth (AOD) and Angstrom Exponent (AE). Even though DT-O does have "dust-like" models to choose from, dust is not identified a priori before inversion. The "dust-like" models are not true "dust models" as they are spherical and do not have enough absorption at short wavelengths, so retrieved AOD and AE for dusty regions tends to be biased. The inference of "dust" is based on postprocessing criteria for AOD and AE by users. Dust aerosol has known spectral signatures in the near-UV (Deep blue), visible, and thermal infrared (TIR) wavelength regions. Multiple dust detection algorithms have been developed over the years with varying detection capabilities. Here, we test a few of these dust detection algorithms, to determine whether they can be useful to help inform the choices made by the DT-O algorithm. We evaluate the following methods: The multichannel imager (MCI) algorithm uses spectral threshold tests in (0.47, 0.64, 0.86, 1.38, 2.26, 3.9, 11.0, 12.0 micrometer) channels and spatial uniformity test [Zhao et al., 2010]. The NOAA dust aerosol index (DAI) uses spectral contrast in the blue channels (412nm and 440nm) [Ciren and Kundragunta, 2014]. The MCI is already included as tests within the "Wisconsin" (MOD35) Cloud mask algorithm.

  7. Multispectral glass transparent from visible to thermal infrared

    NASA Astrophysics Data System (ADS)

    Brehault, A.; Calvez, L.; Pain, T.; Adam, P.; Rollin, J.; Zhang, X. H.

    2014-06-01

    The thermal imaging market has experienced a strong growth during the recent years due to continued cost reduction of night vision devices. The development of uncooled focal plane detector arrays is the major reason for the cost reduction. Another reason is the continuous improvement of the optical solution. In this paper, we present a new multispectral material which responds to the increasing demand for optics operating simultaneously in the visible/SWIR (Short Wave InfraRed) and the thermal infrared region. The most important properties of some glasses from the GeS2-Ga2S3- CsCl system are highlighted in this study. A stable composition 15Ga2S3-75GeS2-10CsCl allowed the synthesis of a large glass without crystallization. The refractive index of this glass was precisely measured from 0.6 to 10.4μm by using the Littrow method. The chromatic dispersion was then calculated and compared with other multispectral materials.

  8. Visibility through the gaseous smoke in airborne remote sensing using a DSLR camera

    NASA Astrophysics Data System (ADS)

    Chabok, Mirahmad; Millington, Andrew; Hacker, Jorg M.; McGrath, Andrew J.

    2016-08-01

    Visibility and clarity of remotely sensed images acquired by consumer grade DSLR cameras, mounted on an unmanned aerial vehicle or a manned aircraft, are critical factors in obtaining accurate and detailed information from any area of interest. The presence of substantial haze, fog or gaseous smoke particles; caused, for example, by an active bushfire at the time of data capture, will dramatically reduce image visibility and quality. Although most modern hyperspectral imaging sensors are capable of capturing a large number of narrow range bands of the shortwave and thermal infrared spectral range, which have the potential to penetrate smoke and haze, the resulting images do not contain sufficient spatial detail to enable locating important objects or assist search and rescue or similar applications which require high resolution information. We introduce a new method for penetrating gaseous smoke without compromising spatial resolution using a single modified DSLR camera in conjunction with image processing techniques which effectively improves the visibility of objects in the captured images. This is achieved by modifying a DSLR camera and adding a custom optical filter to enable it to capture wavelengths from 480-1200nm (R, G and Near Infrared) instead of the standard RGB bands (400-700nm). With this modified camera mounted on an aircraft, images were acquired over an area polluted by gaseous smoke from an active bushfire. Processed data using our proposed method shows significant visibility improvements compared with other existing solutions.

  9. Electrowetting Variable Optics for Visible and Infrared Applications

    NASA Astrophysics Data System (ADS)

    Watson, Alexander Maxwell

    Miniaturized variable optical devices are important for the fields of medical technology, optical communication, and consumer imaging devices. Areas ranging from endoscopy and optogenetics to atomic clocks and imaging all benefit from versatile optical systems. These applications all require precise and rapid control of imaging focal depth and lateral scanning. Electrowetting variable optics is one emergent technology that has the capability to provide focus tuning, beam steering, and even phase modulation in a small and robust package which requires no moving parts. Furthermore, electrowetting based devices there are attractive due to their transmissive nature, polarization insensitivity, low insertion loss, low electrical power requirements, and high optical quality. These features mean that electrowetting adaptive optical components are an attractive solution, compared with MEMS and liquid crystal optical components. Electrowetting is a technique that enables control of the shape of a liquid droplet with applied voltage. A conductive droplet on a dielectric surface alters its contact angle due to charges that build up between an underlying electrode and the surface of the droplet. This effect can be used to tune the curvature and tilt of liquids within cavities. The liquid boundary creates a high quality surface to use for lensing or steering applications. This thesis will focus on the development of electrowetting based lenses and prisms and applications in imaging for both visible and infrared wavelengths. Within this dissertation is the first demonstration of electrowetting lenses for phase control, as well as the investigation of non-aqueous electrowetting lens liquids for electrowetting lenses operation in the infrared. Key considerations that affect the performance and reliability are dielectric material and thickness, liquid selection and source of ionic conduction. The optical devices presented herein utilize judicious selection of dielectric material

  10. Measuring black carbon spectral extinction in the visible and infrared

    NASA Astrophysics Data System (ADS)

    Smith, A. J. A.; Peters, D. M.; McPheat, R.; Lukanihins, S.; Grainger, R. G.

    2015-09-01

    This work presents measurements of the spectral extinction of black carbon aerosol from 400 nm to 15 μm. The aerosol was generated using a Miniature Combustion Aerosol Standard soot generator and then allowed to circulate in an aerosol cell where its extinction was measured using a grating spectrometer in the visible and a Fourier transform spectrometer in the infrared. Size distribution, number concentration, and mass extinction cross sections have also been obtained using single-particle aerosol samplers. A mean mass extinction cross section at 550 nm of 8.3 ± 1.6 m2 g-1 is found which, assuming a reasonable single scatter albedo of 0.2, corresponds to a mass absorption cross section of 6.6 ± 1.3 m2 g-1. This compares well with previously reported literature values. Computer analysis of electron microscope images of the particles provides independent confirmation of the size distribution as well as fractal parameters of the black carbon aerosol. The aerosol properties presented in this work are representative of very fresh, uncoated black carbon aerosol. After atmospheric processing of such aerosols (which could include mixing with other constituents and structural changes), different optical properties would be expected.

  11. Automated classification of visible and infrared spectra using cluster analysis

    NASA Astrophysics Data System (ADS)

    Marzo, G. A.; Roush, T. L.; Hogan, R. C.

    2009-08-01

    Planetary space experiments collect large volumes of data whose scientific content requires understanding. Marzo et al. (2006) presented an unsupervised cluster analysis scheme that is able to reduce a spectral data set to a few clusters, allowing for more focused and rapid evaluation of their scientific meaning. Here, we extend the original approach to account for the measurement uncertainty and build a classification scheme. We apply the clustering technique to the ASTER and RELAB libraries of visible and infrared spectral reflectance. These spectral libraries are documented, allowing assignment of a label to each spectrum reflecting its physical and chemical properties. We assess the ability of the original and extended approaches to identify natural clusters of the library spectra and estimate associated uncertainties of the results. We evaluate the scientific meaning of the derived clusters based on the labels contained within each cluster. Once the cluster meanings are defined, we test our classification scheme using a training-testing approach and evaluate the accuracy of assigning the unknown spectra to the correct cluster.

  12. Synegies Between Visible/Near-Infrared Imaging Spectrometry and the Thermal Infrared in an Urban Environment: An Evaluation of the Hyperspectral Infrared Imager (HYSPIRI) Mission

    NASA Technical Reports Server (NTRS)

    Roberts, Dar A.; Quattrochi, Dale A.; Hulley, Glynn C.; Hook, Simon J.; Green, Robert O.

    2012-01-01

    A majority of the human population lives in urban areas and as such, the quality of urban environments is becoming increasingly important to the human population. Furthermore, these areas are major sources of environmental contaminants and sinks of energy and materials. Remote sensing provides an improved understanding of urban areas and their impacts by mapping urban extent, urban composition (vegetation and impervious cover fractions), and urban radiation balance through measures of albedo, emissivity and land surface temperature (LST). Recently, the National Research Council (NRC) completed an assessment of remote sensing needs for the next decade (NRC, 2007), proposing several missions suitable for urban studies, including a visible, near-infrared and shortwave infrared (VSWIR) imaging spectrometer and a multispectral thermal infrared (TIR) instrument called the Hyperspectral Infrared Imagery (HyspIRI). In this talk, we introduce the HyspIRI mission, focusing on potential synergies between VSWIR and TIR data in an urban area. We evaluate potential synergies using an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and MODIS-ASTER (MASTER) image pair acquired over Santa Barbara, United States. AVIRIS data were analyzed at their native spatial resolutions (7.5m VSWIR and 15m TIR), and aggregated 60 m spatial resolution similar to HyspIRI. Surface reflectance was calculated using ACORN and a ground reflectance target to remove atmospheric and sensor artifacts. MASTER data were processed to generate estimates of spectral emissivity and LST using Modtran radiative transfer code and the ASTER Temperature Emissivity Separation algorithm. A spectral library of common urban materials, including urban vegetation, roofs and roads was assembled from combined AVIRIS and field-measured reflectance spectra. LST and emissivity were also retrieved from MASTER and reflectance/emissivity spectra for a subset of urban materials were retrieved from co-located MASTER and

  13. Novel compact airborne platform for remote sensing applications using the Hyper-Cam infrared hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Turcotte, Caroline S.; Puckrin, Eldon; Aube, Françoys; Farley, Vincent; Savary, Simon; Chamberland, Martin

    2013-05-01

    High resolution broad-band imagery in the visible and infrared bands provides valuable detection capabilities based on target shapes and temperatures. However, the spectral resolution provided by a hyperspectral imager adds a spectral dimension to the measurements, which leads to an additional means of detecting and identifying targets based on their spectral signature. The Telops Hyper-Cam sensor is an interferometer-based imaging system that enables the spatial and spectral analysis of targets using a single sensor. It is based on the Fourier-transform technology, which yields high spectral resolution and enables a high accuracy radiometric calibration. It provides datacubes of up to 320×256 pixels at spectral resolutions as fine as 0.25 cm-1. The LWIR version covers the 8.0 to 11.8 μm spectral range. The Hyper-Cam has been recently integrated and flown on a novel airborne gyro-stabilized platform inside a fixed-wing aircraft. The new platform, more compact and more advanced than its predecessor, is described in this paper. The first results of target detection and identification are also presented.

  14. Combined use of visible, reflected infrared, and thermal infrared images for mapping Hawaiian lava flows

    NASA Technical Reports Server (NTRS)

    Abrams, Michael; Abbott, Elsa; Kahle, Anne

    1991-01-01

    The weathering of Hawaiian basalts is accompanied by chemical and physical changes of the surfaces. These changes have been mapped using remote sensing data from the visible and reflected infrared and thermal infrared wavelength regions. They are related to the physical breakdown of surface chill coats, the development and erosion of silica coatings, the oxidation of mafic minerals, and the development of vegetation cover. These effects show systematic behavior with age and can be mapped using the image data and related to relative ages of pahoehoe and aa flows. The thermal data are sensitive to silica rind development and fine structure of the scene; the reflectance data show the degree of oxidation and differentiate vegetation from aa and cinders. Together, data from the two wavelength regions show more than either separately. The combined data potentially provide a powerful tool for mapping basalt flows in arid to semiarid volcanic environments.

  15. Far-Infrared Astronomy with The Kuiper Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Hildebrand, Roger, H.

    1997-01-01

    This report summarizes work made possible by NASA's Kuiper Airborne Observatory. The results of the work have appeared in over 80 papers. The publications fall in three main areas: instrumentation, observations, and analysis. Although there is considerable overlap between these categories it will be convenient to group them separately.

  16. Visible/Infrared Imaging Spectroscopy and Energy-Resolving Detectors

    NASA Astrophysics Data System (ADS)

    Eisenhauer, Frank; Raab, Walfried

    2015-08-01

    Imaging spectroscopy has seen rapid progress over the past 25 years, leading to breakthroughs in many fields of astronomy that would not have been otherwise possible. This review overviews the visible/infrared imaging spectroscopy techniques as well as energy-resolving detectors. We introduce the working principle of scanning Fabry-Perot and Fourier transform spectrometers and explain the most common integral field concepts based on mirror slicers, lenslet arrays, and fibers. The main advantage of integral field spectrographs is the simultaneous measurement of spatial and spectral information. Although Fabry-Perot and Fourier transform spectrometers can provide a larger field of view, it is ultimately the higher sensitivity of integral field units that make them the technique of choice. This is arguably the case for image slicers, which make the most efficient use of the available detector pixels and have equal or higher transmission than lenslet arrays and fiber integral field units, respectively. We also address the more specific issues of large étendue operation, focal ratio degradation, anamorphic magnification, and diffraction-limited operation. This review also covers the emerging technology of energy-resolving detectors, which promise very simple and efficient instrument designs. These energy-resolving detectors are based on superconducting thin film technology and exploit either the very small superconducting energy to count the number of quasi-particles excited in the absorption of the photon or the extremely steep phase transition between the normal- and superconducting phase to measure a temperature increase. We have put special emphasis on an overview of the underlying physical phenomena as well as on the recent technological progress and astronomical path finder experiments.

  17. Application of airborne infrared technology to monitor building heat loss. [Michigan

    NASA Technical Reports Server (NTRS)

    Tanis, F. J.; Sampson, R. E.

    1977-01-01

    The application of airborne infrared technology to the requirements for energy conservation in buildings was studied. Quantitative airborne data of the City of Ypsilanti, Michigan, were collected and processed to identify roof temperatures. A thermal scanner was flown at an altitude of 1,200 feet with two thermal bands 8.2-9.3 micrometers and 10.4-12.5 micrometers recorded by an analog system. Calibration was achieved by standard hot and cold plates. Using a thermal model to interpret ceiling insulation status, environmental factors were found to influence the relation between roof temperature and insulation. These include interior and sky temperatures, roofing materials, and the pitch and orientation of the roof. A follow-up mail survey established the ability to identify insulated and uninsulated houses from the airborne infrared data.

  18. Using Visible/Near-Infrared Spectroscopy to Identify Cryptotephra Layers

    NASA Astrophysics Data System (ADS)

    McCanta, M. C.; Thomson, B. J.; Fisher, E.

    2014-12-01

    Continually accumulating marine sediments incorporate tephra layers within their depositional record that can be linked to individual explosive volcanic events. These layers can range from several meters in thickness, to discrete layers invisible to the naked eye (cryptotephra). Identification of cryptotephra layers is paramount for complete characterization of the eruptive record of a volcanic center, not just the largest eruptive events. However, cryptotephra recognition is hampered by their small volume in most drill cores. A non-destructive method to distinguish tephra layers, particularly those of a high silica nature which may not be readily detectable with magnetic methods, is visible/near-infrared (Vis/NIR) spectroscopy. The Vis/NIR region of the light spectrum contains strong absorption features due to charge-transfer absorptions in transition metals (dominated by iron) and vibration and overtone bands due to hydroxyl and water (including near 1.4 μm, 1.9 μm, and 2.2-2.5 μm). The exact position and nature of these bands provide a means to identify various carbonate-, hydroxyl-, iron-, phyllosilicate-, sulfate-, and water-bearing minerals (e.g., Pieters and Englert, 1993). We produced a series of mixtures of hemipelagic sediment and tephra which were used to identify band positions and features which strongly correlate with the presence of tephra (see figure). The addition of ~15-20 wt.% tephra to a sediment results in recognizable spectral changes. The mixture data was used to create a MATLAB program to run unknown sample analyses through. We then used an ASD FieldSpec to collect Vis/NIR data (0.39-2.5 μm) on the upper 10 m of core collected during IODP 340 (U1396C) off the coast of Montserrat at 0.5 cm resolution and applied our tephra recognition program to this data. We identified 29 potential cryptotephra layers in the 10 m analyzed. Dissolution techniques are being completed to corroborate the spectral data.

  19. Fresh Soil Sensing using Visible and Near Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Maleki, M. R.

    2009-04-01

    Fast, precise and affordable soil analytical techniques are needed for the determination of soil fertility of each zone of a field in site specific land management. The objective of this poster is to demonstrate how nutrients can be estimated from fresh soil using visible (VIS) and near infrared (NIR) spectroscopy method. This could be carried out by summarizing the methodology to develop a calibration model for soil phosphorus with the VIS-NIR spectroscopy method. Obviously, it can be simply extended for other nutrients with the same methodology. A large samples set should be collected from different fields with a wide range of soil type and texture. The samples in this set should be represented a wide range of moisture content and soil nutrient which is desired to be calibrated by the spectroscopy technique. Immediately after sampling, the samples should be kept in a cold room (± 1 °C) until the time of the spectral measurement and the chemical analysis. The samples should be taken from the cold room one hour before the spectral measurement to ensure that the samples were at room temperature and no condensation occurs on the optical instruments. Each soil sample was thoroughly mixed and debris such as plant material and stones were removed. The soil sample was divided into three parts, one part for spectral measurement, another part for chemical analysis and the rest was archived. The part for chemical analysis should be examined for their soil nutrients. A small amount of soil (about 30 g) should be placed in a small plastic petridish (e.g. 7.5 mm depth and 30 mm diameter). The soil in the petridish should be first pressed and then carefully levelled in order to obtain a smooth surface for a maximum light reflectance. Soil samples should be put under the spectrophotometer. Three reflectance spectra should be measured on each soil specimen by rotating the plastic cups over 120°. Having finished measuring, the reflectance data should be put against the chemical

  20. High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska

    USGS Publications Warehouse

    Wessels, Rick L.; Vaughan, R. Greg; Patrick, Matthew R.; Coombs, Michelle L.

    2013-01-01

    A combination of satellite and airborne high-resolution visible and thermal infrared (TIR) image data detected and measured changes at Redoubt Volcano during the 2008–2009 unrest and eruption. The TIR sensors detected persistent elevated temperatures at summit ice-melt holes as seismicity and gas emissions increased in late 2008 to March 2009. A phreatic explosion on 15 March was followed by more than 19 magmatic explosive events from 23 March to 4 April that produced high-altitude ash clouds and large lahars. Two (or three) lava domes extruded and were destroyed between 23 March and 4 April. After 4 April, the eruption extruded a large lava dome that continued to grow until at least early July 2009.

  1. High spectral resolution airborne short wave infrared hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Wei, Liqing; Yuan, Liyin; Wang, Yueming; Zhuang, Xiaoqiong

    2016-05-01

    Short Wave InfraRed(SWIR) spectral imager is good at detecting difference between materials and penetrating fog and mist. High spectral resolution SWIR hyperspectral imager plays a key role in developing earth observing technology. Hyperspectral data cube can help band selections that is very important for multispectral imager design. Up to now, the spectral resolution of many SWIR hyperspectral imagers is about 10nm. A high sensitivity airborne SWIR hyperspectral imager with narrower spectral band will be presented. The system consists of TMA telescope, slit, spectrometer with planar blazed grating and high sensitivity MCT FPA. The spectral sampling interval is about 3nm. The IFOV is 0.5mrad. To eliminate the influence of the thermal background, a cold shield is designed in the dewar. The pixel number of spatial dimension is 640. Performance measurement in laboratory and image analysis for flight test will also be presented.

  2. Improved Remote Sensing Retrieval of Land Surface Temperature in the Thermal Infrared (TIR) Using Visible/Short Wave Infrared (VSWIR) Imaging Spectrometer Estimated Water Vapor

    NASA Astrophysics Data System (ADS)

    Grigsby, S.; Hulley, G. C.; Roberts, D. A.; Scheele, C. J.; Ustin, S.; Alsina, M. M.

    2014-12-01

    Land surface temperature (LST) is an important parameter in many ecological studies, where processes such as evapotranspiration have impacts at temperature gradients less than 1 K. Current errors in standard MODIS and ASTER LST products are greater than 1 K, and for ASTER can be greater than 2 K in humid conditions due to incomplete atmospheric correction of atmospheric water vapor. Estimates of water vapor, either derived from visible-to-shortwave-infrared (VSWIR) remote sensing data or taken from weather simulation data such as NCEP, can be combined with coincident Thermal-Infrared (TIR) remote sensing data to yield improved accuracy in LST measurements. This study compares LST retrieval accuracies derived using the standard JPL MASTER Temperature Emissivity Separation (TES) algorithm, and the Water Vapor Scaling (WVS) atmospheric correction method proposed for the Hyperspectral Infrared Imager, or HyspIRI, mission with ground observations. The 2011 ER-2 Delano/Lost Hills flights acquired TIR data from the MODIS/ASTER Simulator (MASTER) and VSWIR data from Airborne Visible InfraRed Imaging Spectrometer (AVIRIS) instruments flown concurrently. The TES and WVS retrieval methods are run with and without high spatial resolution AVIRIS-derived water vapor maps to assess the improvement using VSWIR water vapor estimates. We find improvement using VSWIR derived water vapor maps in both cases, with the WVS method being most accurate overall. For closed canopy agricultural vegetation we observed canopy temperature retrieval RMSEs of 0.49 K and 0.70 K using the WVS method on MASTER data with and without AVIRIS derived water vapor, respectively.

  3. Design of camouflage material for visible and near infrared based on thin film technology

    NASA Astrophysics Data System (ADS)

    Miao, Lei; Shi, Jia-ming; Zhao, Da-peng; Liu, Hao; Wang, Chao; Xu, Yan-liang

    2015-11-01

    Visible light and near infrared based camouflage materials achieve good stealth under traditional optical detection equipment but its spectral differences with green plants can be taken advantage of by high spectrum based detection technologies. Based on the thin structure of bandpass filter, we designed an optical film with both green and near infrared spectrum. We conducted simulations using transfer matrix methods and optimized the result by simplex methods. The spectral reflectance curve of the proposed thin film matches that of green plants, and experiments show that the proposed thin film achieve good invisibility under visible light and near infrared in a wide viewing angle.

  4. Robust pedestrian detection by combining visible and thermal infrared cameras.

    PubMed

    Lee, Ji Hoon; Choi, Jong-Suk; Jeon, Eun Som; Kim, Yeong Gon; Le, Toan Thanh; Shin, Kwang Yong; Lee, Hyeon Chang; Park, Kang Ryoung

    2015-05-05

    With the development of intelligent surveillance systems, the need for accurate detection of pedestrians by cameras has increased. However, most of the previous studies use a single camera system, either a visible light or thermal camera, and their performances are affected by various factors such as shadow, illumination change, occlusion, and higher background temperatures. To overcome these problems, we propose a new method of detecting pedestrians using a dual camera system that combines visible light and thermal cameras, which are robust in various outdoor environments such as mornings, afternoons, night and rainy days. Our research is novel, compared to previous works, in the following four ways: First, we implement the dual camera system where the axes of visible light and thermal cameras are parallel in the horizontal direction. We obtain a geometric transform matrix that represents the relationship between these two camera axes. Second, two background images for visible light and thermal cameras are adaptively updated based on the pixel difference between an input thermal and pre-stored thermal background images. Third, by background subtraction of thermal image considering the temperature characteristics of background and size filtering with morphological operation, the candidates from whole image (CWI) in the thermal image is obtained. The positions of CWI (obtained by background subtraction and the procedures of shadow removal, morphological operation, size filtering, and filtering of the ratio of height to width) in the visible light image are projected on those in the thermal image by using the geometric transform matrix, and the searching regions for pedestrians are defined in the thermal image. Fourth, within these searching regions, the candidates from the searching image region (CSI) of pedestrians in the thermal image are detected. The final areas of pedestrians are located by combining the detected positions of the CWI and CSI of the thermal

  5. On the visibility of airborne volcanic ash and other aerosols from the pilot's perspective in flight

    NASA Astrophysics Data System (ADS)

    Weinzierl, B.; Sauer, D.; Minikin, A.; Reitebuch, O.; Dahlkötter, F.; Mayer, B.; Emde, C.; Tegen, I.; Gasteiger, J.; Petzold, A.; Veira, A.; Kueppers, U.; Schumann, U.

    2012-04-01

    In April 2010, the volcanic ash cloud from the Eyjafjalla volcano in Iceland strongly impacted aviation in Europe: more than 100 000 flights were cancelled affecting more than 10 million passengers. Several incidents in the past have shown that volcanic ash may have severe consequences on aviation. Therefore, one operational problem is whether a pilot has the means to avoid flying through potentially dangerous volcanic ash just by visual observation of the sky out of the cockpit of an aircraft. The goal of our study is to assess whether it is possible from the pilot's perspective in flight to detect the presence of volcanic ash and to distinguish between volcanic ash and other aerosols just by sight. In our presentation, we focus the comparison with other aerosols on aerosol types impacting aviation. Besides volcanic ash, dust storms are known to be avoided by aircraft. We approach the question on the visibility of volcanic ash and other aerosol layers in flight starting from the inspection of photographs taken during the Eyjafjalla volcanic ash research flights with the DLR Falcon in April/May 2010 and mass concentrations measured during those flights. Furthermore we use airborne data from the Saharan Mineral Dust Experiments (SAMUM) in 2006 and 2008. We complement this analysis with idealized radiative transfer simulations with libRadtran for a variety of selected viewing geometries. Both aerosol types, Saharan mineral dust and volcanic ash, show an enhanced coarse mode (> 1 µm) aerosol concentration, but volcanic ash aerosol additionally contains a significant number of Aitken mode particles (< 150 nm), which are not present in mineral dust. Volcanic ash is slightly more absorbing than mineral dust, and the spectral behaviour of the refractive index is slightly different. According to our simulations, these differences are not detectable just by human eye. The consequences of our study for aircraft operation are the following: under clear sky conditions

  6. Mid-Infrared Spectroscopy of Mercury from the Kuiper Airborne Observatory

    NASA Astrophysics Data System (ADS)

    Sprague, A. L.; Witteborn, F. C.; Kozlowski, R. W. H.; Wooden, D. H.

    1996-03-01

    We present mid-infrared (5 - 10mic) spectroscopic measurements of the planet Mercury obtained from the Kuiper Airborne Observatory (KAO) using the High Efficiency Infrared Faint Object Grating Spectrograph (HIFOGS). Spectra show features characteristic of plagioclase feldspar that was previously observed near 120 deg mercurian longitude. The spectra also show spectral features that could be interpreted indicative of the presence of pyrrhotite (pyrr). An analysis that fully accounts for the effects of large field of view (FOV), thermal gradients, rough surface and absolute calibration is still underway.

  7. The airborne infrared scanner as a geophysical research tool

    USGS Publications Warehouse

    Friedman, Jules D.

    1970-01-01

    The infrared scanner is proving to be an effective anomaly-mapping tool, albeit one which depicts surface emission directly and heat mass transfer from depths only indirectly and at a threshold level 50 to 100 times the normal conductive heat flow of the earth. Moreover, successive terrain observations are affected by time-dependent variables such as the diurnal and seasonal warming and cooling cycle of a point on the earth's surface. In planning precise air borne surveys of radiant flux from the earth's surface, account must be taken of background noise created by variations in micrometeorological factors and emissivity of surface materials, as well as the diurnal temperature cycle. The effect of the diurnal cycle may be minimized by planning predawn aerial surveys. In fact, the diurnal change is very small for most water bodies and the emissivity factor for water (e) =~ 1 so a minimum background noise is characteristic of scanner records of calm water surfaces.

  8. An Airborne Infrared Telescope and Spectrograph for Solar Eclipse Observations

    NASA Astrophysics Data System (ADS)

    DeLuca, Edward E.; Cheimets, Peter; Golub, Leon

    2014-06-01

    The solar infrared spectrum offers great possibilities for direct spatially resolved measurements of the solar coronal magnetic fields, via imaging of the plasma that is constrained to follow the magnetic field direction and via spectro-polarimetry that permits measurement of the field strength in the corona. Energy stored in coronal magnetic fields is released in flares and coronal mass ejections (CME) and provides the ultimate source of energy for space weather. The large scale structure of the coronal field, and the opening up of the field in a transition zone between the closed and open corona determines the speed and structure of the solar wind, providing the background environment through which CMEs propagate. At present our only direct measurements of the solar magnetic fields are in the photosphere and chromosphere. The ability to determine where and why the corona transitions from closed to open, combined with measurements of the field strength via infrared coronal spectro-polarimetry will give us a powerful new tool in our quest to develop the next generation of forecasting models.We describe a first step in achieving this goal: a proposal for a new IR telescope, image stabilization system, and spectrometer, for the NCAR HIPER GV aircraft. The telescope/spectrograph will operate in the 2-6micron wavelength region, during solar eclipses, starting with the trans-north American eclipse in August 2017. The HIAPER aircraft flying at ~35,000 ft will provide an excellent platform for IR observations. Our imaging and spectroscopy experiment will show the distribution and intensity of IR forbidden lines in the solar corona.

  9. Studying soil properties using visible and near infrared spectral analysis

    NASA Astrophysics Data System (ADS)

    Moretti, S.; Garfagnoli, F.; Innocenti, L.; Chiarantini, L.

    2009-04-01

    This research is carried out inside the DIGISOIL Project, whose purposes are the integration and improvement of in situ and proximal measurement technologies, for the assessment of soil properties and soil degradation indicators, going form the sensing technologies to their integration and their application in digital soil mapping. The study area is located in the Virginio river basin, about 30 km south of Firenze, in the Chianti area, where soils with agricultural suitability have a high economic value connected to the production of internationally famous wines and olive oils. The most common soil threats, such as erosion and landslide, may determine huge economic losses, which must be considered in farming management practices. This basin has a length of about 23 km for a basin area of around 60,3 Km2. Geological formations outcropping in the area are Pliocene to Pleistocene marine and lacustrine sediments in beds with almost horizontal bedding. Vineyards, olive groves and annual crops are the main types of land use. A typical Mediterranean climate prevails with a dry summer followed by intense and sometimes prolonged rainfall in autumn, decreasing in winter. In this study, three types of VNIR and SWIR techniques, operating at different scales and in different environments (laboratory spectroscopy, portable field spectroscopy) are integrated to rapidly quantify various soil characteristics, in order to acquire data for assessing the risk of occurrence for typically agricultural practice-related soil threats (swelling, compaction, erosion, landslides, organic matter decline, ect.) and to collect ground data in order to build up a spectral library to be used in image analysis from air-borne and satellite sensors. Difficulties encountered in imaging spectroscopy, such as influence of measurements conditions, atmospheric attenuation, scene dependency and sampling representation are investigated and mathematical pre-treatments, using proper algorithms, are applied and

  10. GOES imager visible-to-infrared channel registration using star observations

    NASA Astrophysics Data System (ADS)

    Chu, Donald; Baucom, Jeanette G.; Baltimore, Perry; Bremer, James C.

    2003-11-01

    Due to optical misalignment, visible and infrared channels of the Geostationary Operational Environmental Satellite (GOES) I-M Imager may not be properly registered. This "co-registration" error is currently estimated by comparing groups of visible and infrared observation residuals from the GOES Orbit and Attitude Tracking System (OATS). To make the channel-to-channel comparison more direct, it was proposed to compare individual observations rather than groups of observations. This has already been done for landmarks but not for stars. Stars would help determine nighttime co-registration when visible landmarks are not available. Although most stars in the GOES catalog are not detectable in the shortwave infrared channel, many are. Because stars drift west-to-east across the detectors and because of their high observation frequency, stars provide good east-west co-registration information. Due to the large detector fields-of-view, stars do not provide much information about north-south co-registration.

  11. Comparison of spatial variability in visible and near-infrared spectral images

    USGS Publications Warehouse

    Chavez, P.S., Jr.

    1992-01-01

    The visible and near-infrared bands of the Landsat Thematic Mapper (TM) and the Satellite Pour l'Observation de la Terre (SPOT) were analyzed to determine which band contained more spatial variability. It is important for applications that require spatial information, such as those dealing with mapping linear features and automatic image-to-image correlation, to know which spectral band image should be used. Statistical and visual analyses were used in the project. The amount of variance in an 11 by 11 pixel spatial filter and in the first difference at the six spacings of 1, 5, 11, 23, 47, and 95 pixels was computed for the visible and near-infrared bands. The results indicate that the near-infrared band has more spatial variability than the visible band, especially in images covering densely vegetated areas. -Author

  12. Multi-window visual saliency extraction for fusion of visible and infrared images

    NASA Astrophysics Data System (ADS)

    Zhao, Jufeng; Gao, Xiumin; Chen, Yueting; Feng, Huajun; Wang, Daodang

    2016-05-01

    Fusion for visible and infrared images aims to combine the source images of the same scene into a single image with more feature information and better visual performance. In this paper, the authors propose a fusion method based on multi-window visual saliency extraction for visible and infrared images. To extract feature information from infrared and visible images, we design local-window-based frequency-tuned method. With this idea, visual saliency maps are calculated for variable feature information under different local window. These maps show the weights of people's attention upon images for each pixel and region. Enhanced fusion is done using simple weight combination way. Compared with the classical and state-of-the-art approaches, the experimental results demonstrate the proposed approach runs efficiently and performs better than other methods, especially in visual performance and details enhancement.

  13. Infrared laser diode with visible illuminator for biomedical stimulation

    NASA Astrophysics Data System (ADS)

    Strek, Wieslaw; Podbielska, Halina; Szafranski, C.; Kuzmin, Andrei N.; Ges, J. A.; Ryabtsev, Gennadii I.

    1995-02-01

    The special laser diode device (LDD) leasing in the near infrared region (IR) with two wavelengths: (lambda) 1 equals 850 nm and (lambda) 2 equals 1000 nm, designed for laser therapy, is presented. This device is characterized by a unique feature, namely a separate built-in illuminator, operating in 670 nm. The special construction of LDD and the illuminator enables the user to visualize exactly the surface irradiated by IR radiation. The exposure time and the output of laser power are also controlled and can be displayed on the LED monitor at the front panel. This new device, described here, is compact, low cost, and user friendly.

  14. Validation of Satellite Ammonia Retrievals using Airborne Hyperspectral Thermal-Infrared Spectrometry

    NASA Astrophysics Data System (ADS)

    Tratt, D. M.; Hall, J. L.; Chang, C. S.; Qian, J.; Clarisse, L.; Van Damme, M.; Clerbaux, C.; Hurtmans, D.; Coheur, P.

    2011-12-01

    We demonstrate the utility of a new airborne sensor with the requisite spatial, spectral, and radiometric resolution to characterize "point" sources of ammonia emission. Flights were conducted over California's San Joaquin Valley, which is a region of intensive agriculture and animal husbandry that has been identified as one of the single largest sources of atmospheric free ammonia worldwide. Airborne data acquisition operations were coordinated with daytime overpasses of the Infrared Atmospheric Sounding Interferometer (IASI) aboard the European Space Agency's MetOp-A platform. IASI is capable of measuring total columns of ammonia and the primary purpose of this investigation was to compare and validate the IASI ammonia product against high-spatial-resolution airborne retrievals acquired contemporaneously over the same footprint. The ~12-km pixel size of the IASI satellite measurements cannot resolve the local-scale variability of ammonia abundance and consequently cannot characterize the often compact source emissions. The nominal 2-m pixel size of the airborne data revealed variability of ammonia concentration at several different scales within the IASI footprint. At this pixel size, well-defined plumes issuing from individual dairy facilities could be imaged and their dispersion characteristics resolved. Retrieved ammonia concentrations in excess of 50 ppb were inferred for some of the strongest discrete plumes.

  15. Multidirectional visible and shortwave infrared polarimeter for atmospheric aerosol and cloud observation: OSIRIS (Observing System Including PolaRisation in the Solar Infrared Spectrum)

    NASA Astrophysics Data System (ADS)

    Auriol, F.; Léon, J.-F.; Balois, J.-Y.; Verwaerde, C.; François, P.; Riedi, J.; Parol, F.; Waquet, F.; Tanré, D.; Goloub, P.

    2008-12-01

    The aim of this project is to improve the characterization of radiative and microphysical properties of aerosols and clouds in the atmosphere. These two atmospheric components and their interactions are among the main sources of uncertainty in the numerical forecast of climate change. In this context, we have designed a new airborne polarimeter for measuring directional, total and polarized radiances in the 440 to 2200 nm spectral range. This instrument is based on the POLDER concept, instrument that is currently aboard the PARASOL microsatellite. This new sensor consists in two optical systems for the visible to near infrared range (440 to 940 nm) and the shortwave infrared (940 to 2200 nm). Each optical system is composed of a wide field-of-view optics (114° and 105° respectively) associated to two rotating wheels for interferential filters and analysers respectively, and a 2D array of detectors. For each channel, the total and polarized radiances are computed using the measurements performed with the three analysers shifted by an angle of 60°. Thanks to the large field of view of the optics, any target is seen under several viewing angles during the aircraft motion. This type of instrument has been designed for the retrieval of optical thickness and microphysical properties of aerosols as well as for the determination of microphysical, macrophysical and radiative properties of clouds. In this paper, we will present this new instrument design and some preliminary results recently obtained during the first field campaign in May 2008 over Europe.

  16. Summaries of the Sixth Annual JPL Airborne Earth Science Workshop. Volume 2; AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Kim, Yun-Jin (Editor)

    1996-01-01

    The Sixth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on March 4-8, 1996, was divided into two smaller workshops:(1) The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, and The Airborne Synthetic Aperture Radar (AIRSAR) workshop. This current paper, Volume 2 of the Summaries of the Sixth Annual JPL Airborne Earth Science Workshop, presents the summaries for The Airborne Synthetic Aperture Radar (AIRSAR) workshop.

  17. Vehicle/Atmosphere Interaction Glows: Far Ultraviolet, Visible, and Infrared

    NASA Technical Reports Server (NTRS)

    Swenson, G.

    1999-01-01

    Spacecraft glow information has been gathered from a number of spacecraft including Atmospheric and Dynamic satellites, and Space Shuttles (numerous flights) with dedicated pallet flow observations on STS-39 (DOD) and STS-62 (NASA). In addition, a larger number of laboratory experiments with low energy oxygen beam studies have made important contributions to glow understanding. The following report provides information on three engineering models developed for spacecraft glow including the far ultraviolet to ultraviolet (1400-4000 A), and infrared (0.9-40 microns) spectral regions. The models include effects resulting from atmospheric density/altitude, spacecraft temperature, spacecraft material, and ram angle. Glow brightness would be predicted as a function of distance from surfaces for all wavelengths.

  18. Development of silicon-germanium visible-near infrared arrays

    NASA Astrophysics Data System (ADS)

    Zeller, John W.; Rouse, Caitlin; Efstathiadis, Harry; Haldar, Pradeep; Lewis, Jay S.; Dhar, Nibir K.; Wijewarnasuriya, Priyalal; Puri, Yash R.; Sood, Ashok K.

    2016-05-01

    Photodetectors based on germanium which do not require cooling and can provide good near-infrared (NIR) detection performance offer a low-cost alternative to conventional infrared sensors based on material systems such as InGaAs, InSb, and HgCdTe. As a result of the significant difference in thermal expansion coefficients between germanium and silicon, tensile strain incorporated into Ge epitaxial layers deposited on Si utilizing specialized growth processes can extend the operational range of detection to 1600 nm and longer wavelengths. We have fabricated Ge based PIN photodetectors on 300 mm diameter Si wafers to take advantage of high throughput, large-area complementary metal-oxide semiconductor (CMOS) technology. This device fabrication process involves low temperature epitaxial deposition of Ge to form a thin p+ (boron) Ge seed/buffer layer, and subsequent higher temperature deposition of a thicker Ge intrinsic layer. This is followed by selective ion implantation of phosphorus of various concentrations to form n+ Ge regions, deposition of a passivating oxide cap, and then top copper contacts to complete the PIN detector devices. Various techniques including transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) have been employed to characterize the material and structural properties of the epitaxially grown layers and fabricated detector devices, and these results are presented. The I-V response of the photodetector devices with and without illumination was also measured, for which the Ge based photodetectors consistently exhibited low dark currents of around ~1 nA at -1 V bias.

  19. High Resolution Observations of Magnetic Elements in the Visible and the Infrared

    NASA Astrophysics Data System (ADS)

    Rimmele, T.; Lin, H.

    1997-05-01

    High resolution observations of magnetic elements in the visible and infrared. We report on multi-wavelength observations of plage regions obtained at the Vacuum Tower Telescope at NSO/Sac-Peak . The data set includes high resolution images in the G-band (0.43 mu ), the visible (0.69 mu ) continuum and the infrared (1.6 mu ) continuum. In addition, deep integration full Stokes vector measurements in the FeI 1.56 mu lines, as well as, Ca-K slit jaw images were obtained. G-band bright points, which are observed mostly in supergranular lanes, are also visible as bright points in the visible continuum. Although the infrared observations are limited in spatial resolution to about 0."4 (the diffraction limit of the VTT/SP), the data indicates that G-band bright points are also bright in the infrared (1.6 mu ). We also discuss and compare properties of magnetic knots and small pores. Magnetic knots, which recently also have been referred to as azimuth centers (Lites et al. 1994), by definition show no darkening in individual continuum images. However, in the time-averaged imaging data, and in particular in the infrared, azimuth centers appear as dark features, which are clearly distinguishable from the quiet sun background. In the infrared most azimuth centers are visible as dark features even in individual snapshots. Many azimuth centers as well as some small pores are surrounded by a highly structured bright ring, which becomes more apparent with increasing height of formation. Results of the polarization analysis in the FeI 1.56 mu lines, including measurements of weak fields, are presented as well.

  20. Enhanced visible and near-infrared capabilities of the JET mirror-linked divertor spectroscopy system

    SciTech Connect

    Lomanowski, B. A. Sharples, R. M.; Meigs, A. G.; Conway, N. J.; Zastrow, K.-D.; Heesterman, P.; Kinna, D. [EURATOM Collaboration: JET-EFDA Team

    2014-11-15

    The mirror-linked divertor spectroscopy diagnostic on JET has been upgraded with a new visible and near-infrared grating and filtered spectroscopy system. New capabilities include extended near-infrared coverage up to 1875 nm, capturing the hydrogen Paschen series, as well as a 2 kHz frame rate filtered imaging camera system for fast measurements of impurity (Be II) and deuterium Dα, Dβ, Dγ line emission in the outer divertor. The expanded system provides unique capabilities for studying spatially resolved divertor plasma dynamics at near-ELM resolved timescales as well as a test bed for feasibility assessment of near-infrared spectroscopy.

  1. Visible and Near Infrared Fluorescence Spectral Flow Cytometry

    PubMed Central

    Nolan, John P.; Condello, Danilo; Duggan, Erika; Naivar, Mark; Novo, David

    2013-01-01

    There is a long standing interest in measuring complete emission spectra from individual cells in flow cytometry. We have developed flow cytometry instruments and analysis approaches to enable this to be done routinely and robustly. Our spectral flow cytometers use a holographic grating to disperse light from single cells onto a CCD for high speed, wavelength-resolved detection. Customized software allows the single cell spectral data to be displayed and analyzed to produce new spectra-derived parameters. We show that familiar reference and calibration beads can be employed to quantitatively assess instrument performance. We use microspheres stained with six different quantum dots to compare a virtual bandpass filter approach with classic least squares (CLS) spectral unmixing, and then use antibody capture beads and CLS unmixing to demonstrate immunophenotyping of peripheral blood mononuclear cells using spectral flow cytometry. Finally, we characterize and evaluate several near infrared (NIR) emitting fluorophores for use in spectral flow cytometry. Spectral flow cytometry offers a number of attractive features for single cell analysis, including a simplified optical path, high spectral resolution, and streamlined approaches to quantitative multiparameter measurements. The availability of robust instrumentation, software, and analysis approaches will facilitate the development of spectral flow cytometry applications. PMID:23225549

  2. Visible and infrared remote imaging of hazardous waste: A review

    USGS Publications Warehouse

    Slonecker, Terrence; Fisher, Gary B.; Aiello, Danielle P.; Haack, Barry

    2010-01-01

    One of the critical global environmental problems is human and ecological exposure to hazardous wastes from agricultural, industrial, military and mining activities. These wastes often include heavy metals, hydrocarbons and other organic chemicals. Traditional field and laboratory detection and monitoring of these wastes are generally expensive and time consuming. The synoptic perspective of overhead remote imaging can be very useful for the detection and remediation of hazardous wastes. Aerial photography has a long and effective record in waste site evaluations. Aerial photographic archives allow temporal evaluation and change detection by visual interpretation. Multispectral aircraft and satellite systems have been successfully employed in both spectral and morphological analysis of hazardous wastes on the landscape and emerging hyperspectral sensors have permitted determination of the specific contaminants by processing strategies using the tens or hundreds of acquired wavelengths in the solar reflected and/or thermal infrared parts of the electromagnetic spectrum. This paper reviews the literature of remote sensing and overhead imaging in the context of hazardous waste and discusses future monitoring needs and emerging scientific research areas.

  3. Visible/near-infrared spectroscopy to predict water holding capacity in broiler breast meat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visible/Near-infrared spectroscopy (Vis/NIRS) was examined as a tool for rapidly determining water holding capacity (WHC) in broiler breast meat. Both partial least squares (PLS) and principal component analysis (PCA) models were developed to relate Vis/NIRS spectra of 85 broiler breast meat sample...

  4. Use of visible and near-infrared spectroscopy to predict pork longissimus lean color stability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluated using visible and near-infrared (VIS/NIR) spectroscopy to predict lean color stability in pork loin chops. Spectra were collected immediately following and approximately 1 h after rib removal from 1,208 loins. Loins were aged for 14 d before a 2.54-cm chop was placed in simula...

  5. Postmortem chemical changes in poultry breast meat monitored with visible-near infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken meat undergoes significant chemical and structural changes with postmortem time that influence meat quality characteristics. The objective of this study was to measure the visible-near infrared (vis-NIR) spectral differences in broiler breast fillets at 0.5, 4, 24, and 120 h postmortem. Mu...

  6. Correlation of quality measurements to visible-near infrared spectra of pasteurized egg

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A twelve week study was conducted on the egg albumen from both pasteurized and non-pasteurized shell eggs using visible-near infrared spectroscopy. Correlation of the chemical changes detected in the spectra to the measurement of Haugh units (measure of interior egg quality) was carried out using ch...

  7. Chemometric correlation of shelf life, quality measurements, and visible-near infrared spectra of pasteurized eggs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A twelve week study was conducted on the egg albumen from both pasteurized and non-pasteurized shell eggs using visible-near infrared spectroscopy. Correlation of the chemical changes detected in the spectra to the measurement of Haugh units (measure of interior egg quality) was carried out using pr...

  8. High-speed poultry inspection using visible/near-infrared spectrophotometer

    NASA Astrophysics Data System (ADS)

    Chao, Kuanglin; Chen, Yud-Ren

    2004-03-01

    A visible/near-infrared spectroscopic system for high-speed on-line poultry carcass inspection was developed and demonstrated. The inspection system, which was an area scanning system designed to measure the interactance spectra of poultry carcasses in the visible to near-infrared regions, consisted of a fiber optic probe, a spectrograph, a spectroscopic charge coupled device detector, a quartz tungsten halogen light source, an industrial computer, and inhouse developed software modules. On-line trials of the visible/near-infrared chicken inspection system were conducted during a 5-day period in a poultry processing plant in Athens, Georgia. Spectra (431-943 nm) of 450 wholesome and 426 unwholesome chicken carcasses were measured. The instrument measured the spectra of veterinarian-selected carcasses on a processing line running at speeds of 140 and 180 birds per minute. Results showed this visible/near-infrared system can be used to differentiate between wholesome and unwholesome poultry carcasses at high speeds. For the 140 bird per minute line speed, the best model achieved classification accuracies of 95% for wholesome and 92% for unwholesome birds. For the 180 bird per minute line speed, the best model achieved classification accuracies of 94% and 92% for wholesome and unwholesome birds, respectively. The system is ready to be implemented for operation on high speed poultry processing lines.

  9. Visible and near-infrared spectroscopy detects queen honey bee insemination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The abdomens of honey bee queens, the heads of worker bees, and the ventriculi of worker bees were analyzed by visible and near-infrared spectroscopy. Mated honey bee queens could be distinguished from virgin queens by their spectra with 100% accuracy. Also, the heads of worker bees taken from the...

  10. Visible and Near-Infrared Spectroscopy Detects Honey Bee Queen Insemination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The abdomens of honey bee queens, the heads of worker bees, and the ventriculi of worker bees were analyzed by visible and near-infrared spectroscopy. Mated honey bee queens could be distinguished from virgin queens by their spectra with 100% accuracy. Also, the heads of worker bees taken from the ...

  11. Effects of ultraviolet radiation, visible light, and infrared radiation on erythema and pigmentation: a review.

    PubMed

    Sklar, Lindsay R; Almutawa, Fahad; Lim, Henry W; Hamzavi, Iltefat

    2013-01-01

    The effects of ultraviolet radiation, visible light, and infrared radiation on cutaneous erythema, immediate pigment darkening, persistent pigment darkening, and delayed tanning are affected by a variety of factors. Some of these factors include the depth of cutaneous penetration of the specific wavelength, the individual skin type, and the absorption spectra of the different chromophores in the skin. UVB is an effective spectrum to induce erythema, which is followed by delayed tanning. UVA induces immediate pigment darkening, persistent pigment darkening, and delayed tanning. At high doses, UVA (primarily UVA2) can also induce erythema in individuals with skin types I-II. Visible light has been shown to induce erythema and a tanning response in dark skin, but not in fair skinned individuals. Infrared radiation produces erythema, which is probably a thermal effect. In this article we reviewed the available literature on the effects of ultraviolet radiation, visible light, and infrared radiation on the skin in regards to erythema and pigmentation. Much remains to be learned on the cutaneous effects of visible light and infrared radiation.

  12. Visible/near-infrared spectroscopy for discrimination of HLB-infected citrus leaves from healthy leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Researchers have used various hyperspectral systems, covering several areas of the electromagnetic spectrum to investigate all types of disease/plant interactions. The purpose of this research was to investigate using visible and near-infrared (400-1100nm) spectroscopy to differentiate HLB infected...

  13. Detection of sucrose content of sugar beet by visible/near-infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sucrose content is the most important quality parameter in the production and processing of sugar beet. This paper reports on the application of visible/near-infrared (Vis-NIR) spectroscopy for measurement of the sucrose content of sugar beet. Two portable spectrometers, covering the spectral region...

  14. Determination of sucrose content in sugar beet by portable visible and near-infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The feasibility of visible and near-infrared spectroscopy for measurement of the sucrose content of sugar beet was investigated with two portable spectrometers that cover the spectral regions of 400-1,100 nm and 900-1,600 nm, respectively. Spectra in interactance mode were collected first from 398 i...

  15. Hyperspectral visible-near infrared imaging for the detection of waxed rice

    NASA Astrophysics Data System (ADS)

    Zhao, Mantong

    2014-11-01

    Presently, unscrupulous traders in the market use the industrial wax to wax the rice. The industrial wax is a particularly hazardous substance. Visible-near infrared hyperspectral images (400-1,000 nm) can be used for the detection of the waxed rice and the non-waxed rice. This study was carried out to find effective testing methods based on the visible-near infrared imaging spectrometry to detect whether the rice was waxed or not. An imaging spectroscopy system was assembled to acquire hyperspectral images from 80 grains of waxed rice and 80 grains of non-waxed rice over visible and near infrared spectral region. Spectra of 100 grains of rice were analyzed by principal component analysis (PCA) to extract the information of hyperspectral images. PCA provides an effective compressed representation of the spectral signal of each pixel in the spectral domain. We used PCA to acquire the effective wavelengths from the spectra. Based on the effective wavelengths, the predict models were set up by using partial least squares (PLS) analysis and linear discriminant analysis (LDA). Also, compared with the PLS of 80% for the waxed rice and 86.7% for the non-waxed rice detection rate, LDA gives 93.3% and 96.7% detection rate. The results demonstrated that the LDA could detect the waxed rice better, while illustrating the hyperspectral imaging technique with the visible-near infrared region could be a reliable method for the waxed rice detection.

  16. Electrically tunable selective reflection of light from ultraviolet to visible and infrared by heliconical cholesterics.

    PubMed

    Xiang, Jie; Li, Yannian; Li, Quan; Paterson, Daniel A; Storey, John M D; Imrie, Corrie T; Lavrentovich, Oleg D

    2015-05-20

    Electrical tuning of selective reflection of light is achieved in a very broad spectral range from ultraviolet to visible and infrared by an oblique helicoidal state of a cholesteric liquid crystal in a wide temperature range (including room temperature). The phenomenon offers potential applications in tunable smart windows, lasers, optical filters and limiters, as well as in displays. PMID:25821155

  17. Differences in visible and near-infrared light reflectance between orange fruit and leaves

    NASA Technical Reports Server (NTRS)

    Gausman, H. W.; Escobar, D. E.; Berumen, A.

    1975-01-01

    The objective was to find the best time during the season (April 26, 1972 to January 8, 1973) to distinguish orange fruit from leaves by spectrophotometrically determining at 10-day intervals when the difference in visible (550- and 650-nm wavelengths) and near-infrared (850-nm wavelength) light reflectance between fruit and nearby leaves was largest. December 5 to January 8 was the best time to distinguish fruit from leaves. During this period the fruit's color was rapidly changing from green to yellow, and the difference in visible light reflectance between fruit and leaves was largest. The difference in near-infrared reflectance between leaves and fruit remained essentially constant during ripening when the difference in visible light reflectance between leaves and fruit was largest.

  18. Optical Alignment and Diffraction Analysis for AIRES: An Airborne Infrared Echelle Spectrometer

    NASA Technical Reports Server (NTRS)

    Haas, Michael R.; Fonda, Mark (Technical Monitor)

    2002-01-01

    The optical design is presented for a long-slit grating spectrometer known as AIRES (Airborne InfraRed Echelle Spectrometer). The instrument employs two gratings in series: a small order sorter and a large steeply blazed echelle. The optical path includes four pupil and four field stops, including two narrow slits. A detailed diffraction analysis is performed using GLAD by Applied Optics Research to evaluate critical trade-offs between optical throughput, spectral resolution, and system weight and volume. The effects of slit width, slit length, oversizing the second slit relative to the first, on- vs off-axis throughput, and clipping at the pupil stops and other optical elements are discussed.

  19. GOES-R Advanced Baseline Imager: spectral response functions and radiometric biases with the NPP Visible Infrared Imaging Radiometer Suite evaluated for desert calibration sites.

    PubMed

    Pearlman, Aaron; Pogorzala, David; Cao, Changyong

    2013-11-01

    The Advanced Baseline Imager (ABI), which will be launched in late 2015 on the National Oceanic and Atmospheric Administration's Geostationary Operational Environmental Satellite R-series satellite, will be evaluated in terms of its data quality postlaunch through comparisons with other satellite sensors such as the recently launched Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership satellite. The ABI has completed much of its prelaunch characterization and its developers have generated and released its channel spectral response functions (response versus wavelength). Using these responses and constraining a radiative transfer model with ground reflectance, aerosol, and water vapor measurements, we simulate observed top of atmosphere (TOA) reflectances for analogous visible and near infrared channels of the VIIRS and ABI sensors at the Sonoran Desert and White Sands National Monument sites and calculate the radiometric biases and their uncertainties. We also calculate sensor TOA reflectances using aircraft hyperspectral data from the Airborne Visible/Infrared Imaging Spectrometer to validate the uncertainties in several of the ABI and VIIRS channels and discuss the potential for validating the others. Once on-orbit, calibration scientists can use these biases to ensure ABI data quality and consistency to support the numerical weather prediction community and other data users. They can also use the results for ABI or VIIRS anomaly detection and resolution.

  20. The development of large-aperture test system of infrared camera and visible CCD camera

    NASA Astrophysics Data System (ADS)

    Li, Yingwen; Geng, Anbing; Wang, Bo; Wang, Haitao; Wu, Yanying

    2015-10-01

    Infrared camera and CCD camera dual-band imaging system is used in many equipment and application widely. If it is tested using the traditional infrared camera test system and visible CCD test system, 2 times of installation and alignment are needed in the test procedure. The large-aperture test system of infrared camera and visible CCD camera uses the common large-aperture reflection collimator, target wheel, frame-grabber, computer which reduces the cost and the time of installation and alignment. Multiple-frame averaging algorithm is used to reduce the influence of random noise. Athermal optical design is adopted to reduce the change of focal length location change of collimator when the environmental temperature is changing, and the image quality of the collimator of large field of view and test accuracy are also improved. Its performance is the same as that of the exotic congener and is much cheaper. It will have a good market.

  1. Combined autofluorescence and Raman spectroscopy method for skin tumor detection in visible and near infrared regions

    NASA Astrophysics Data System (ADS)

    Zakharov, V. P.; Bratchenko, I. A.; Artemyev, D. N.; Myakinin, O. O.; Khristoforova, Y. A.; Kozlov, S. V.; Moryatov, A. A.

    2015-07-01

    The combined application of Raman and autofluorescence spectroscopy in visible and near infrared regions for the analysis of malignant neoplasms of human skin was demonstrated. Ex vivo experiments were performed for 130 skin tissue samples: 28 malignant melanomas, 19 basal cell carcinomas, 15 benign tumors, 9 nevi and 59 normal tissues. Proposed method of Raman spectra analysis allows for malignant melanoma differentiating from other skin tissues with accuracy of 84% (sensitivity of 97%, specificity of 72%). Autofluorescence analysis in near infrared and visible regions helped us to increase the diagnostic accuracy by 5-10%. Registration of autofluorescence in near infrared region is realized in one optical unit with Raman spectroscopy. Thus, the proposed method of combined skin tissues study makes possible simultaneous large skin area study with autofluorescence spectra analysis and precise neoplasm type determination with Raman spectroscopy.

  2. SPECTRAL IRRADIANCE CALIBRATION IN THE INFRARED. XVII. ZERO-MAGNITUDE BROADBAND FLUX REFERENCE FOR VISIBLE-TO-INFRARED PHOTOMETRY

    SciTech Connect

    Engelke, Charles W.; Price, Stephan D.; Kraemer, Kathleen E.

    2010-12-15

    The absolutely calibrated infrared (IR) stellar spectra of standard stars described by Engelke et al. are being extended into the visible and will span a continuous wavelength range from {approx}0.35 {mu}m to 35.0 {mu}m. This paper, which is a continuation of the series on calibration initiated with Cohen et al., presents the foundation of this extension. We find that due to various irregularities Vega ({alpha} Lyr) is not suitable for its traditional role as the primary visible or near-infrared standard star. We therefore define a new zero-point flux that is independent of Vega and, as far as is feasible, uses measured spectral energy distributions (SEDs) and fluxes derived from photometry. The calibrated primary stars now underpinning this zero-point definition are 109 Vir in the visible and Sirius ({alpha} CMa) in the infrared. The resulting zero-point SED tests well against solar analog data presented by Rieke et al. while also maintaining an unambiguous link to specific calibration stars, thus providing a pragmatic range of options for any researcher wishing to tie it to a given set of photometry.

  3. Airborne Hyperspectral Infrared Imaging Survey of the Southern San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Lynch, D. K.; Tratt, D. M.; Buckland, K. N.; Johnson, P. D.

    2014-12-01

    The San Andreas Fault (SAF) between Desert Hot Springs and Bombay Beach has been surveyed with Mako, an airborne hyperspectral imager operating across the wavelength range 7.6-13.2 μm in the thermal-infrared (TIR) spectral region. The data were acquired with a 4-km swath width centered on the SAF, and many tectonic features are recorded in the imagery. Spectral analysis using diagnostic features of minerals can identify rocks, soils and vegetation. Mako imagery can also locate rupture zones and measure slip distances. Designed and built by The Aerospace Corporation, the innovative and highly capable airborne imaging spectrometer used for this work enables low-noise performance (NEΔT ≲ 0.1 K @ 10 μm) at small pixel IFOV (0.55 mrad) and high frame rates, making possible an area-coverage rate of 20 km2 per minute with 2-m ground resolution from 12,500 ft (3.8 km) above-ground altitude. Since its commissioning in 2010, Mako has been used in numerous studies involving other earthquake fault systems (Hector Mine, S. Bristol Mts.), mapping of surface geology, geothermal sources (fumaroles near the Salton Sea), urban surveys, and the detection, quantification, and tracking of natural and anthropogenic gaseous emission plumes. Mako is available for airborne field studies and new applications are of particular interest. It can be flown at any altitude below 20,000 ft to achieve the desired GSD.

  4. Fusion of infrared and visible images for night-vision context enhancement.

    PubMed

    Zhou, Zhiqiang; Dong, Mingjie; Xie, Xiaozhu; Gao, Zhifeng

    2016-08-10

    Because of the poor lighting conditions at night time, visible images are often fused with corresponding infrared (IR) images for context enhancement of the scenes in night vision. In this paper, we present a novel night-vision context enhancement algorithm through IR and visible image fusion with the guided filter. First, to enhance the visibility of poorly illuminated details in the visible image before the fusion, an adaptive enhancement method is developed by incorporating the processes of dynamic range compression and contrast restoration based on the guided filter. Then, a hybrid multi-scale decomposition based on the guided filter is introduced to inject the IR image information into the visible image through a multi-scale fusion approach. Moreover, a perceptual-based regularization parameter selection method is used to determine the relative amount of the injected IR spectral features by comparing the perceptual saliency of the IR and visible image information. This fusion method can successfully transfer the important IR image information into the fused image, and simultaneously preserve the details and background scenery in the input visible image. Experimental results show that the proposed algorithm is able to achieve better context enhancement results in night vision. PMID:27534499

  5. Sea surface velocities from visible and infrared multispectral atmospheric mapping sensor imagery

    NASA Technical Reports Server (NTRS)

    Pope, P. A.; Emery, W. J.; Radebaugh, M.

    1992-01-01

    High resolution (100 m), sequential Multispectral Atmospheric Mapping Sensor (MAMS) images were used in a study to calculate advective surface velocities using the Maximum Cross Correlation (MCC) technique. Radiance and brightness temperature gradient magnitude images were formed from visible (0.48 microns) and infrared (11.12 microns) image pairs, respectively, of Chandeleur Sound, which is a shallow body of water northeast of the Mississippi delta, at 145546 GMT and 170701 GMT on 30 Mar. 1989. The gradient magnitude images enhanced the surface water feature boundaries, and a lower cutoff on the gradient magnitudes calculated allowed the undesirable sunglare and backscatter gradients in the visible images, and the water vapor absorption gradients in the infrared images, to be reduced in strength. Requiring high (greater than 0.4) maximum cross correlation coefficients and spatial coherence of the vector field aided in the selection of an optimal template size of 10 x 10 pixels (first image) and search limit of 20 pixels (second image) to use in the MCC technique. Use of these optimum input parameters to the MCC algorithm, and high correlation and spatial coherence filtering of the resulting velocity field from the MCC calculation yielded a clustered velocity distribution over the visible and infrared gradient images. The velocity field calculated from the visible gradient image pair agreed well with a subjective analysis of the motion, but the velocity field from the infrared gradient image pair did not. This was attributed to the changing shapes of the gradient features, their nonuniqueness, and large displacements relative to the mean distance between them. These problems implied a lower repeat time for the imagery was needed in order to improve the velocity field derived from gradient imagery. Suggestions are given for optimizing the repeat time of sequential imagery when using the MCC method for motion studies. Applying the MCC method to the infrared

  6. Strong visible light emission from well-aligned multiwalled carbon nanotube films under infrared laser irradiation

    SciTech Connect

    Zhang Yong; Gong Tao; Liu Wenjin; Zhang Xianfeng; Chang Jianguo; Wang Kunlin; Wu Dehai

    2005-10-24

    We report strong and brilliant visible light emission from well-aligned multiwalled carbon nanotube (AMWNT) films under infrared (IR) laser irradiation with wavelength at 1.06 and 10.6 {mu}m, respectively. The AMWNT film shows a high durability against laser irradiation and achieved a conversion from IR laser to visible light. It is a good candidate for optical converter. Light emission spectra versus different wavelengths and various powers were found to have similar line shapes. It could be explained as combination of laser-induced photoluminescence and resistive heating.

  7. Phase closure retrieval in an infrared-to-visible upconversion interferometer for high resolution astronomical imaging.

    PubMed

    Ceus, Damien; Tonello, Alessandro; Grossard, Ludovic; Delage, Laurent; Reynaud, François; Herrmann, Harald; Sohler, Wolfgang

    2011-04-25

    This paper demonstrates the use of a nonlinear upconversion process to observe an infrared source through a telescope array detecting the interferometric signal in the visible domain. We experimentally demonstrate the possibility to retrieve information on the phase of the object spectrum of an infrared source by using a three-arm upconversion interferometer. We focus our study on the acquisition of phase information of the complex visibility by means of the phase closure technique. In our experimental demonstration, a laboratory binary star with an adjustable photometric ratio is used as a test source. A real time comparison between a standard three-arm interferometer and our new concept using upconversion by sum-frequency generation demonstrates the preservation of phase information which is essential for image reconstruction.

  8. An improved fusion algorithm for infrared and visible images based on multi-scale transform

    NASA Astrophysics Data System (ADS)

    Li, He; Liu, Lei; Huang, Wei; Yue, Chao

    2016-01-01

    In this paper, an improved fusion algorithm for infrared and visible images based on multi-scale transform is proposed. First of all, Morphology-Hat transform is used for an infrared image and a visible image separately. Then two images were decomposed into high-frequency and low-frequency images by contourlet transform (CT). The fusion strategy of high-frequency images is based on mean gradient and the fusion strategy of low-frequency images is based on Principal Component Analysis (PCA). Finally, the final fused image is obtained by using the inverse contourlet transform (ICT). The experiments and results demonstrate that the proposed method can significantly improve image fusion performance, accomplish notable target information and high contrast and preserve rich details information at the same time.

  9. Visible to infrared photoluminescence from gold nanoparticles embedded in germano-silicate glass fiber.

    PubMed

    Lin, Aoxiang; Son, Dong Hoon; Ahn, Il Ho; Song, G Hugh; Han, Won-Taek

    2007-05-14

    Germano-silicate glass fiber containing gold nanoparticles was developed by modified chemical vapor deposition and solution doping processes. Pumping with 488 nm Argon ion laser, we firstly report on the visible to infrared photoluminescence of the gold nanoparticles embedded in the core of the germano-silicate fibers. The surface plasmon resonance absorption peak at 498.4 nm and the visible to infrared photoluminescence over the range of 600 nm approximately 1560 nm were found and explained according to the interband and intraband electronic transitions of Au atoms. The averaged quantum efficiencies of the photoluminescence at 833 nm and 1536 nm were estimated to be 5.75 x 10(-8) and 2.01 x 10(-9), respectively.

  10. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.

    PubMed

    Holick, Michael F

    2016-03-01

    Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation.

  11. Forensic inspection of document using visible and near-infrared spectral imaging

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Wang, Guiqiang; Xu, Xiaojing; Yu, Tao; Yang, Zhicheng

    2010-11-01

    In this study, the potential of visible and near-infrared spectral imaging as a technique of document inspection was examined. Doubtful documents are often found in economic cases, distinguished between original and added strokes and detected blurry characters are very useful for judgment. Burned, covered and rinsed documents in which the characters can't be identified with naked eyes were experimentally studied with a visible spectral imaging technique. Meanwhile, the same color inks were detected by both visible and near-infrared imaging spectrometers. Classification of spectral images was carried out in specialist spectral imaging software packager Misystem provided by Institute of Forensic Science. The technique significantly improved the detection of many documents, especially those that might be considered of poor quality or borderline characters. The visible spectral imaging was successful in detecting the burnt Chinese characters produced using pencils. It was possible to form spectral images showing the strokes even covered by Chinese ink by means of imaging at characteristic frequencies. As inks have very different spectral from the clothes, contribution and contrast of the rinsed lines and illegible seal words on clothes were clearly enhanced. By examining the spectral images from the inks, it was possible to determine whether the same color inks were written by the different pens. The results also show that the near-infrared spectrometer is better than visible one in distinguishing the same inks. In blind testing, spectral imaging was shown to achieve an average 85.1% chance of success. The results reveal the wide applications of spectral imaging in document evidence analysis. The potential of this technique in forensic science will be more apparent along with the further and deeper studies.

  12. The optical properties of mouse skin in the visible and near infrared spectral regions.

    PubMed

    Sabino, Caetano P; Deana, Alessandro M; Yoshimura, Tania M; da Silva, Daniela F T; França, Cristiane M; Hamblin, Michael R; Ribeiro, Martha S

    2016-07-01

    Visible and near-infrared radiation is now widely employed in health science and technology. Pre-clinical trials are still essential to allow appropriate translation of optical methods into clinical practice. Our results stress the importance of considering the mouse strain and gender when planning pre-clinical experiments that depend on light-skin interactions. Here, we evaluated the optical properties of depilated albino and pigmented mouse skin using reproducible methods to determine parameters that have wide applicability in biomedical optics. Light penetration depth (δ), absorption (μa), reduced scattering (μ's) and reduced attenuation (μ't) coefficients were calculated using the Kubelka-Munk model of photon transport and spectrophotometric measurements. Within a broad wavelength coverage (400-1400nm), the main optical tissue interactions of visible and near infrared radiation could be inferred. Histological analysis was performed to correlate the findings with tissue composition and structure. Disperse melanin granules present in depilated pigmented mouse skin were shown to be irrelevant for light absorption. Gender mostly affected optical properties in the visible range due to variations in blood and abundance of dense connective tissue. On the other hand, mouse strains could produce more variations in the hydration level of skin, leading to changes in absorption in the infrared spectral region. A spectral region of minimal light attenuation, commonly referred as the "optical window", was observed between 600 and 1350nm. PMID:27101274

  13. Online inspection of poultry carcasses using a visible/near-infrared spectrophotometer

    NASA Astrophysics Data System (ADS)

    Chen, Yud-Ren; Hruschka, William R.; Early, Howard

    1999-01-01

    The Instrumentation and Sensing Laboratory (ISL) has developed an industrial prototype diode-array visible/near-infrared (Vis/NIR) spectrophotometer system for inspecting poultry for diseased and defective carcasses on-line. The ISL design is based on the principle that wholesome and diseased and defective birds have different chemical compositions of tissues and may have different skin color. This visible/near- infrared spectrophotometer system has been tested off-line at 60 and 90 birds per minute. On-line trials of the visible/near-infrared chicken carcass inspection system were conducted during an 8-day period in a slaughter plant in New Holland, Pennsylvania, where spectra (470 - 960 nm) of 1174 normal and 576 abnormal (diseased and/or defective) chicken carcasses were measured. The instrument measured the spectra of veterinarian-selected carcasses as they passed on a processing line at a speed of 70 birds per minute. Classification models using principal component analysis as a data pretreatment for input into neural networks were able to classify the carcasses from the spectral data with a success rate of 95%. Data from 3 days can predict the subsequent two days' chickens with high accuracy. This accuracy was consistent with the results obtained previously on off-line studies. Thus, the method shows promise for separation of diseased and defective carcasses from wholesome carcasses in a partially automated inspection system. Details of the models using various training regimens are discussed.

  14. Visible and infrared tracking based on multi-view multi-kernel fusion model

    NASA Astrophysics Data System (ADS)

    Yun, Xiao; Jing, Zhongliang; Jin, Bo

    2016-04-01

    In the visual tracking problem, fusion of visible and infrared sensors provides complementarily useful features and can consistently help distinguish the target from the background efficiently. Recently, multi-view learning has received growing attention due to its enormous potential in combining diverse view features containing consistent and complementary characteristics. Therefore, in this paper, a visible and infrared fusion tracking algorithm based on multi-view multi-kernel fusion (MVMKF) model is presented. The proposed MVMKF model considers the diversities of visible and infrared views and embeds complementary information from them. Furthermore, the multi-kernel framework is used to learn the importance of view features so that an integrated appearance representation is made with regard to the respective performance. Besides, the tracking task is completed with naive Bayes classifier in sophisticated compressive feature domain, considering the high performances of classifier-level and sophisticated feature-level learning for multiple views. The experimental results demonstrate that the MVMKF tracking algorithm performs well in terms of accuracy and robustness.

  15. The optical properties of mouse skin in the visible and near infrared spectral regions.

    PubMed

    Sabino, Caetano P; Deana, Alessandro M; Yoshimura, Tania M; da Silva, Daniela F T; França, Cristiane M; Hamblin, Michael R; Ribeiro, Martha S

    2016-07-01

    Visible and near-infrared radiation is now widely employed in health science and technology. Pre-clinical trials are still essential to allow appropriate translation of optical methods into clinical practice. Our results stress the importance of considering the mouse strain and gender when planning pre-clinical experiments that depend on light-skin interactions. Here, we evaluated the optical properties of depilated albino and pigmented mouse skin using reproducible methods to determine parameters that have wide applicability in biomedical optics. Light penetration depth (δ), absorption (μa), reduced scattering (μ's) and reduced attenuation (μ't) coefficients were calculated using the Kubelka-Munk model of photon transport and spectrophotometric measurements. Within a broad wavelength coverage (400-1400nm), the main optical tissue interactions of visible and near infrared radiation could be inferred. Histological analysis was performed to correlate the findings with tissue composition and structure. Disperse melanin granules present in depilated pigmented mouse skin were shown to be irrelevant for light absorption. Gender mostly affected optical properties in the visible range due to variations in blood and abundance of dense connective tissue. On the other hand, mouse strains could produce more variations in the hydration level of skin, leading to changes in absorption in the infrared spectral region. A spectral region of minimal light attenuation, commonly referred as the "optical window", was observed between 600 and 1350nm.

  16. Broadband Near-Infrared to Visible Upconversion in Quantum Dot-Quantum Well Heterostructures.

    PubMed

    Teitelboim, Ayelet; Oron, Dan

    2016-01-26

    Upconversion is a nonlinear process in which two, or more, long wavelength photons are converted to a shorter wavelength photon. It holds great promise for bioimaging, enabling spatially resolved imaging in a scattering specimen and for photovoltaic devices as a means to surpass the Shockley-Queisser efficiency limit. Here, we present dual near-infrared and visible emitting PbSe/CdSe/CdS nanocrystals able to upconvert a broad range of NIR wavelengths to visible emission at room temperature. The synthesis is a three-step process, which enables versatility and tunability of both the visible emission color and the NIR absorption edge. Using this method, one can achieve a range of desired upconverted emission peak positions with a suitable NIR band gap. PMID:26592258

  17. Femtosecond laser pulses in the near-infrared produce visible lesions in the primate eye

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; Toth, Cynthia A.; Noojin, Gary D.; Stolarski, David J.; Rockwell, Benjamin A.

    1998-01-01

    Single pulses in the near-infrared (1060 and 1064 nanometers) were used to measure ophthalmoscopically minimum visible lesion (MVL) thresholds in the rhesus monkey eyes for pulsewidths of 7 nanoseconds (ns), 20 picoseconds (ps), and 150 femtoseconds (fs). MVL thresholds for 1 hour reading and 24 hour reading are reported as the 50% probability for damage (ED50) together with their fiducial limits. These measured thresholds are compared with previously reported thresholds for near-IR and visible wavelengths for the complete range of pulsewidths (ns, ps, and fs). Threshold doses were lower at the 24 hour reading than at the 1 hour reading and both ED50 for the fs pulsewidths were less than 25% of those for ns pulsewidths. MVL thresholds ranged from 19 (mu) J at 7 ns down to 1 (mu) J at 150 fs. Thresholds measured for the nanosecond and picosecond pulsewidths using infrared laser pulses were an order of magnitude larger than for the visible wavelengths at similar pulsewidths while the 150 fs threshold was only about double the value for the 580 nm visible wavelength at 90 fs.

  18. Infrared and visible image fusion based on region growing and contourlet transform

    NASA Astrophysics Data System (ADS)

    Zhao, Bingjie; Gao, Wei; Song, Zongxi

    2013-09-01

    According to the characteristics of infrared and visible images, a new image fusion method based on region growing and contourlet transform is proposed in this paper. To obtain more complementary information, the method is designed as a two-stage procedure. Firstly, the input infrared image is processed with region growing to segment the thermal target. Different fusion rules are adopted in target and background regions, respectively. For the target region, local energy is utilized as the fusion rule of the first fusion to fuse the thermal target and the visible image, while for the non-target region, we reserve the visible background information. Secondly, in order to fully add original information of the source images and avoid loss of information caused by segmentation, we make the second fusion between the visible image and the result image of the one-stage fusion. For good properties of localization, directionality and anisotropy, we adopt contourlet transform as the second fusion method. Experiments are carried out and the results show that our method is clearer in visual quality and effective in quantitative evaluations and the fused images are better than those resulting of using wavelet transform and contourlet transform.

  19. Visible and near-infrared channel calibration of the GOES-6 VISSR using high-altitude aircraft measurements

    NASA Technical Reports Server (NTRS)

    Smith, Gilbert R.; Levin, Robert H.; Koyanagi, Robert S.; Wrigley, Robert C.

    1989-01-01

    Present and future visible and near-infrared wavelength sensors mounted on operational satellites do not have on-board absolute calibration devices. One means of establishing an in-orbit calibration for a satellite sensor is to make simultaneous measurements of a bright, relatively uniform scene along the satellite view vector from a calibrated instrument on board a high altitude aircraft. Aircraft data were recorded over White Sands, New Mexico, and the coincident aircraft and orbiting satellite data is compared for the visible and near-infrared wavelength channel of the GOES-6 Visible Infrared Spin-Scan Radiometer.

  20. Simulated radiance profiles for automating the interpretation of airborne passive multi-spectral infrared images.

    PubMed

    Sulub, Yusuf; Small, Gary W

    2008-10-01

    Methodology is developed for simulating the radiance profiles acquired from airborne passive multispectral infrared imaging measurements of ground sources of volatile organic compounds (VOCs). The simulation model allows the superposition of pure-component laboratory spectra of VOCs onto spectral backgrounds that simulate those acquired during field measurements conducted with a downward-looking infrared line scanner mounted on an aircraft flying at an altitude of 2000-3000 ft (approximately 600-900 m). Wavelength selectivity in the line scanner is accomplished through the use of a multichannel Hg:Cd:Te detector with up to 16 integrated optical filters. These filters allow the detection of absorption and emission signatures of VOCs superimposed on the upwelling infrared background radiance within the instrumental field of view (FOV). By combining simulated radiance profiles containing analyte signatures with field-collected background signatures, supervised pattern recognition methods can be employed to train automated classifiers for use in detecting the signatures of VOCs during field measurements. The targeted application for this methodology is the use of the imaging system to detect releases of VOCs during emergency response scenarios. In the work described here, the simulation model is combined with piecewise linear discriminant analysis to build automated classifiers for detecting ethanol and methanol. Field data collected during controlled releases of ethanol, as well as during a methanol release from an industrial facility, are used to evaluate the methodology.

  1. Wavelet-Based Visible and Infrared Image Fusion: A Comparative Study.

    PubMed

    Sappa, Angel D; Carvajal, Juan A; Aguilera, Cristhian A; Oliveira, Miguel; Romero, Dennis; Vintimilla, Boris X

    2016-01-01

    This paper evaluates different wavelet-based cross-spectral image fusion strategies adopted to merge visible and infrared images. The objective is to find the best setup independently of the evaluation metric used to measure the performance. Quantitative performance results are obtained with state of the art approaches together with adaptations proposed in the current work. The options evaluated in the current work result from the combination of different setups in the wavelet image decomposition stage together with different fusion strategies for the final merging stage that generates the resulting representation. Most of the approaches evaluate results according to the application for which they are intended for. Sometimes a human observer is selected to judge the quality of the obtained results. In the current work, quantitative values are considered in order to find correlations between setups and performance of obtained results; these correlations can be used to define a criteria for selecting the best fusion strategy for a given pair of cross-spectral images. The whole procedure is evaluated with a large set of correctly registered visible and infrared image pairs, including both Near InfraRed (NIR) and Long Wave InfraRed (LWIR). PMID:27294938

  2. Wavelet-Based Visible and Infrared Image Fusion: A Comparative Study

    PubMed Central

    Sappa, Angel D.; Carvajal, Juan A.; Aguilera, Cristhian A.; Oliveira, Miguel; Romero, Dennis; Vintimilla, Boris X.

    2016-01-01

    This paper evaluates different wavelet-based cross-spectral image fusion strategies adopted to merge visible and infrared images. The objective is to find the best setup independently of the evaluation metric used to measure the performance. Quantitative performance results are obtained with state of the art approaches together with adaptations proposed in the current work. The options evaluated in the current work result from the combination of different setups in the wavelet image decomposition stage together with different fusion strategies for the final merging stage that generates the resulting representation. Most of the approaches evaluate results according to the application for which they are intended for. Sometimes a human observer is selected to judge the quality of the obtained results. In the current work, quantitative values are considered in order to find correlations between setups and performance of obtained results; these correlations can be used to define a criteria for selecting the best fusion strategy for a given pair of cross-spectral images. The whole procedure is evaluated with a large set of correctly registered visible and infrared image pairs, including both Near InfraRed (NIR) and Long Wave InfraRed (LWIR). PMID:27294938

  3. Optical assembly of a visible through thermal infrared multispectral imaging system

    SciTech Connect

    Henson, T.; Bender, S.; Byrd, D.; Rappoport, W.; Shen, G.Y.

    1998-06-01

    The Optical Assembly (OA) for the Multispectral Thermal Imager (MTI) program has been fabricated, assembled, and successfully tested for its performance. It represents a major milestone achieved towards completion of this earth observing E-O imaging sensor that is to be operated in low earth orbit. Along with its wide-field-of-view (WFOV), 1.82{degree} along-track and 1.38{degree} cross-track, and comprehensive on-board calibration system, the pushbroom imaging sensor employs a single mechanically cooled focal plane with 15 spectral bands covering a wavelength range from 0.45 to 10.7 {micro}m. The OA has an off-axis three-mirror anastigmatic (TMA) telescope with a 36-cm unobscured clear aperture. The two key performance criteria, 80% enpixeled energy in the visible and radiometric stability of 1% 1{sigma} in the visible/near-infrared (VNIR) and short wavelength infrared (SWIR), of 1.45% 1{sigma} in the medium wavelength infrared (MWIR), and of 0.53% 1{sigma} long wavelength infrared (LWIR), as well as its low weight (less than 49 kg) and volume constraint (89 cm x 44 cm x 127 cm) drive the overall design configuration of the OA and fabrication requirements.

  4. Wavelet-Based Visible and Infrared Image Fusion: A Comparative Study.

    PubMed

    Sappa, Angel D; Carvajal, Juan A; Aguilera, Cristhian A; Oliveira, Miguel; Romero, Dennis; Vintimilla, Boris X

    2016-06-10

    This paper evaluates different wavelet-based cross-spectral image fusion strategies adopted to merge visible and infrared images. The objective is to find the best setup independently of the evaluation metric used to measure the performance. Quantitative performance results are obtained with state of the art approaches together with adaptations proposed in the current work. The options evaluated in the current work result from the combination of different setups in the wavelet image decomposition stage together with different fusion strategies for the final merging stage that generates the resulting representation. Most of the approaches evaluate results according to the application for which they are intended for. Sometimes a human observer is selected to judge the quality of the obtained results. In the current work, quantitative values are considered in order to find correlations between setups and performance of obtained results; these correlations can be used to define a criteria for selecting the best fusion strategy for a given pair of cross-spectral images. The whole procedure is evaluated with a large set of correctly registered visible and infrared image pairs, including both Near InfraRed (NIR) and Long Wave InfraRed (LWIR).

  5. Toward the Direct Measurement of Coronal Magnetic Fields: An Airborne Infrared Spectrometer for Eclipse Observations

    NASA Astrophysics Data System (ADS)

    Samra, J.; DeLuca, E. E.; Golub, L.; Cheimets, P.

    2014-12-01

    The solar magnetic field enables the heating of the corona and provides its underlying structure. Energy stored in coronal magnetic fields is released in flares and coronal mass ejections (CME) and provides the ultimate source of energy for space weather. Therefore, direct measurements of the coronal magnetic field have significant potential to enhance understanding of coronal dynamics and improve solar forecasting models. Of particular interest are observations of coronal field lines in the transitional region between closed and open flux systems, providing important information on the origin of the slow solar wind. While current instruments routinely observe only the photospheric and chromospheric magnetic fields, a proposed airborne spectrometer will take a step toward the direct observation of coronal fields by measuring plasma emission in the infrared at high spatial and spectral resolution. The targeted lines are four forbidden magnetic dipole transitions between 2 and 4 μm. The airborne system will consist of a telescope, grating spectrometer, and pointing/stabilization system to be flown on the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) during the August 2017 total solar eclipse. The project incorporates several optical engineering challenges, centered around maintaining adequate spectral and spatial resolution in a compact and inexpensive package and on a moving platform. Design studies are currently underway to examine the tradeoffs between various optical geometries and control strategies for the pointing/stabilization system. The results will be presented and interpreted in terms of the consequences for the scientific questions. In addition, results from a laboratory prototype and simulations of the final system will be presented.

  6. Shape distortions induced by convective effect on hot object in visible, near infrared and infrared bands

    NASA Astrophysics Data System (ADS)

    Delmas, Anthony; Maoult, Yannick Le; Buchlin, Jean-Marie; Sentenac, Thierry; Orteu, Jean-José

    2013-04-01

    The goal of this study is to examine the perturbation induced by the convective effect (or mirage effect) on shape measurement and to give an estimation of the error induced. This work explores the mirage effect in different spectral bands and single wavelengths. A numerical approach is adopted and an original setup has been developed in order to investigate easily all the spectral bands of interest with the help of a CCD camera (Si, 0.35-1.1 μm), a near infrared camera (VisGaAs, 0.8-1.7 μm) or infrared cameras (8-12 μm). Displacements due to the perturbation for each spectral band are measured and finally some hints about how to correct them are given.

  7. Airborne testing of a bispectral infrared pushbroom scanner for hotspot detection

    NASA Astrophysics Data System (ADS)

    Lorenz, Eckehard; Skrbek, Wolfgang; Zhukov, Boris

    1999-12-01

    A small Bi-spectral Infrared Detection (BIRD) push broom scanner for a small satellite mission is developed, which is dedicated to the detection and analysis of high temperature events (HTE) including the surrounding background scenario. To avoid the saturation of the detector at high temperatures keeping at the same time a reasonable radiometric resolution for the background a very large dynamic range is required, which will be realized by special adaptive sample techniques. These techniques were proved and verified during special airborne experiments. Using two cameras in different spectral regions (3.4 - 4.2 micrometer and 8.5 - 9.3 micrometer) with a well synchronized sampling mode, it is also possible to detect and analyze hot targets with an extension much less than the nominal ground pixel size. An excellent synchronization of the cameras is required to avoid time expensive matching procedures and therefore to enable a related real time processing. A pre-condition for these sub- pixel techniques is the recognition of the related areas distinguishing them from sun glints and similar false alarm candidates. Analyzing the data of the airborne experiments, the processing algorithms could be tested and improved.

  8. Multispectral decomposition for the removal of out-of-band effects of visible/infrared imaging radiometer suite visible and near-infrared bands.

    PubMed

    Gao, Bo-Cai; Chen, Wei

    2012-06-20

    The visible/infrared imaging radiometer suite (VIIRS) is now onboard the first satellite platform managed by the Joint Polar Satellite System of the National Oceanic and Atmospheric Administration and NASA. It collects scientific data from an altitude of approximately 830 km in 22 narrow bands located in the 0.4-12.5 μm range. The seven visible and near-infrared (VisNIR) bands in the wavelength interval between 0.4-0.9 μm are known to suffer from the out-of-band (OOB) responses--a small amount of radiances far away from the center of a given band that can pass through the filter and reach detectors in the focal plane. A proper treatment of the OOB effects is necessary in order to obtain calibrated at-sensor radiance data [referred to as the Sensor Data Records (SDRs)] from measurements with these bands and subsequently to derive higher-level data products [referred to as the Environmental Data Records (EDRs)]. We have recently developed a new technique, called multispectral decomposition transform (MDT), which can be used to correct/remove the OOB effects of VIIRS VisNIR bands and to recover the true narrow band radiances from the measured radiances containing OOB effects. An MDT matrix is derived from the laboratory-measured filter transmittance functions. The recovery of the narrow band signals is performed through a matrix multiplication--the production between the MDT matrix and a multispectral vector. Hyperspectral imaging data measured from high altitude aircraft and satellite platforms, the complete VIIRS filter functions, and the truncated VIIRS filter functions to narrower spectral intervals, are used to simulate the VIIRS data with and without OOB effects. Our experimental results using the proposed MDT method have demonstrated that the average errors after decomposition are reduced by more than one order of magnitude.

  9. Active airborne infrared laser system for identification of surface rock and minerals

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.; Shumate, M. S.; Nash, D. B.

    1984-01-01

    Emissivity and reflectivity in the thermal infrared spectral region (8-13 microns) may be used to discriminate among rocks and minerals. Although considerable success has been achieved in remote sensing classification of rock types based on emissivity measurements made with NASA's Thermal Infreared Multispectral Scanner (TIMS), classification based on reflectivity offers several advantages: much narrower bandwidths are used, higher signal to noise ratios are possible, and measurements are little affected by surface temperature. As a demonstration, an airborne CO2 laser instrument was flown along the margin of Death Valley, California. Measurements of spectral reflectance collected with this device were compared with emissivity measurements made with the TIMS. Data from either instrument provided the means for recognizing boundaries between geologic units including different rock types and fan surfaces of different ages.

  10. Development of visible/infrared/microwave agriculture classification and biomass estimation algorithms. [Guyton, Oklahoma and Dalhart, Texas

    NASA Technical Reports Server (NTRS)

    Rosenthal, W. D.; Mcfarland, M. J.; Theis, S. W.; Jones, C. L. (Principal Investigator)

    1982-01-01

    Agricultural crop classification models using two or more spectral regions (visible through microwave) are considered in an effort to estimate biomass at Guymon, Oklahoma Dalhart, Texas. Both grounds truth and aerial data were used. Results indicate that inclusion of C, L, and P band active microwave data, from look angles greater than 35 deg from nadir, with visible and infrared data improve crop discrimination and biomass estimates compared to results using only visible and infrared data. The microwave frequencies were sensitive to different biomass levels. The K and C band were sensitive to differences at low biomass levels, while P band was sensitive to differences at high biomass levels. Two indices, one using only active microwave data and the other using data from the middle and near infrared bands, were well correlated to total biomass. It is implied that inclusion of active microwave sensors with visible and infrared sensors on future satellites could aid in crop discrimination and biomass estimation.

  11. Development of visible/infrared/microwave agriculture classification and biomass estimation algorithms, volume 2. [Oklahoma and Texas

    NASA Technical Reports Server (NTRS)

    Rosenthal, W. D.; Mcfarland, M. J.; Theis, S. W.; Jones, C. L. (Principal Investigator)

    1982-01-01

    Agricultural crop classification models using two or more spectral regions (visible through microwave) were developed and tested and biomass was estimated by including microwave with visible and infrared data. The study was conducted at Guymon, Oklahoma and Dalhart, Texas utilizing aircraft multispectral data and ground truth soil moisture and biomass information. Results indicate that inclusion of C, L, and P band active microwave data from look angles greater than 35 deg from nadir with visible and infrared data improved crop discrimination and biomass estimates compared to results using only visible and infrared data. The active microwave frequencies were sensitive to different biomass levels. In addition, two indices, one using only active microwave data and the other using data from the middle and near infrared bands, were well correlated to total biomass.

  12. Midwave infrared and visible sensor performance modeling: small craft identification discrimination criteria for maritime security

    NASA Astrophysics Data System (ADS)

    Krapels, Keith; Driggers, Ronald G.; Deaver, Dawne; Moker, Steven K.; Palmer, John

    2007-10-01

    The new emphasis on Anti-Terrorism and Force Protection (AT/FP), for both shore and sea platform protection, has resulted in a need for infrared imager design and evaluation tools that demonstrate field performance against U.S. Navy AT/FP requirements. In the design of infrared imaging systems for target acquisition, a discrimination criterion is required for successful sensor realization. It characterizes the difficulty of the task being performed by the observer and varies for different target sets. This criterion is used in both assessment of existing infrared sensor and in the design of new conceptual sensors. We collected 12 small craft signatures (military and civilian) in the visible band during the day and the long-wave and midwave infrared spectra in both the day and the night environments. These signatures were processed to determine the targets' characteristic dimension and contrast. They were also processed to band limit the signature's spatial information content (simulating longer range), and a perception experiment was performed to determine the task difficulty (N50 and V50). The results are presented and can be used for Navy and Coast Guard imaging infrared sensor design and evaluation.

  13. Midwave infrared and visible sensor performance modeling: small craft identification discrimination criteria for maritime security.

    PubMed

    Krapels, Keith; Driggers, Ronald G; Deaver, Dawne; Moker, Steven K; Palmer, John

    2007-10-20

    The new emphasis on Anti-Terrorism and Force Protection (AT/FP), for both shore and sea platform protection, has resulted in a need for infrared imager design and evaluation tools that demonstrate field performance against U.S. Navy AT/FP requirements. In the design of infrared imaging systems for target acquisition, a discrimination criterion is required for successful sensor realization. It characterizes the difficulty of the task being performed by the observer and varies for different target sets. This criterion is used in both assessment of existing infrared sensor and in the design of new conceptual sensors. We collected 12 small craft signatures (military and civilian) in the visible band during the day and the long-wave and midwave infrared spectra in both the day and the night environments. These signatures were processed to determine the targets' characteristic dimension and contrast. They were also processed to band limit the signature's spatial information content (simulating longer range), and a perception experiment was performed to determine the task difficulty (N50 and V50). The results are presented and can be used for Navy and Coast Guard imaging infrared sensor design and evaluation.

  14. Leaf Chlorophyll Content Estimation of Winter Wheat Based on Visible and Near-Infrared Sensors.

    PubMed

    Zhang, Jianfeng; Han, Wenting; Huang, Lvwen; Zhang, Zhiyong; Ma, Yimian; Hu, Yamin

    2016-03-25

    The leaf chlorophyll content is one of the most important factors for the growth of winter wheat. Visual and near-infrared sensors are a quick and non-destructive testing technology for the estimation of crop leaf chlorophyll content. In this paper, a new approach is developed for leaf chlorophyll content estimation of winter wheat based on visible and near-infrared sensors. First, the sliding window smoothing (SWS) was integrated with the multiplicative scatter correction (MSC) or the standard normal variable transformation (SNV) to preprocess the reflectance spectra images of wheat leaves. Then, a model for the relationship between the leaf relative chlorophyll content and the reflectance spectra was developed using the partial least squares (PLS) and the back propagation neural network. A total of 300 samples from areas surrounding Yangling, China, were used for the experimental studies. The samples of visible and near-infrared spectroscopy at the wavelength of 450,900 nm were preprocessed using SWS, MSC and SNV. The experimental results indicate that the preprocessing using SWS and SNV and then modeling using PLS can achieve the most accurate estimation, with the correlation coefficient at 0.8492 and the root mean square error at 1.7216. Thus, the proposed approach can be widely used for winter wheat chlorophyll content analysis.

  15. OLBERS: An Interplanetary Probe to Study Visible and Infrared Diffuse Backgrounds

    NASA Astrophysics Data System (ADS)

    Désert, F.-X.

    1995-10-01

    The visible extragalactic background (though as yet undetected) is insufficient to explain the abundance of heavy elements in galaxies: either there should be some diffuse extragalactic light in the near infrared (from 1 to 10 μm) and/or in the far infrared (≥100 μm) if dust has reprocessed the star light. We propose a new space mission to be dedicated to the search and mapping of primordial stellar light from the visible to the mid-infrared (20 μm). In this spectrum range, detectors have reached such a sensitivity that the mission should aim at being (source) photon noise limited, and not any longer background photon noise limited. For that purpose, a small passively cooled telescope with large format CCDs and CIDs could be sent beyond the zodiacal dust cloud (which is absent beyond a solar distance of about 3 AU). In that case, the only remaining foregrounds before reaching the extragalactic background, is due to the Milky Way integrated emission from stars and the diffuse galactic light due to scattering and emission by interstellar dust, which are all unavoidable. Maps of the extragalactic light could be obtained at the arcminute resolution with high signal to noise ratio. This mission is the next logical step after IRAS, COBE and ISO for the study of extragalactic IR backgrounds. It has been proposed as a possible medium-sized mission for the post-horizon 2000 ESA program that could be a piggy back of a planetary mission.

  16. The Artist's Lens: Capturing the World in the Visible and Infrared

    NASA Astrophysics Data System (ADS)

    Shipman, J. S.; Webley, P.; Dehn, J.

    2014-12-01

    We go about our daily lives with our primary sensory input in the visible spectrum. This is but only one of the many available spectra that artists and scientists alike can use to capture and analyze how the world works. Each artist's creative voice comes from individual experiences and their philosophy on how to portray the world around us. Adding infrared technology to the artist's toolkit creates a new opportunity to glimpse into our world through a different set of lenses. By using both the subjective artist's-eye and the critical scientist's mind, we gain unique yet complementary viewpoints when we observe the same physical processes. Using digital SLR and thermal imaging cameras, we will capture still imagery and high-definition videos, at multiple frames per second. We will present examples, such as heat loss in cold environments over time, analyses of different rock structures, and the significance of emissivity on infrared measurements. We will show how these two spectra, the visible and infrared, together provide a novel outreach tool to visualize artistic and scientific principles. Our aim is to cultivate the interest of students of all ages in the arts and geophysical sciences and allow us all to learn more about the world in which we live.

  17. Leaf Chlorophyll Content Estimation of Winter Wheat Based on Visible and Near-Infrared Sensors

    PubMed Central

    Zhang, Jianfeng; Han, Wenting; Huang, Lvwen; Zhang, Zhiyong; Ma, Yimian; Hu, Yamin

    2016-01-01

    The leaf chlorophyll content is one of the most important factors for the growth of winter wheat. Visual and near-infrared sensors are a quick and non-destructive testing technology for the estimation of crop leaf chlorophyll content. In this paper, a new approach is developed for leaf chlorophyll content estimation of winter wheat based on visible and near-infrared sensors. First, the sliding window smoothing (SWS) was integrated with the multiplicative scatter correction (MSC) or the standard normal variable transformation (SNV) to preprocess the reflectance spectra images of wheat leaves. Then, a model for the relationship between the leaf relative chlorophyll content and the reflectance spectra was developed using the partial least squares (PLS) and the back propagation neural network. A total of 300 samples from areas surrounding Yangling, China, were used for the experimental studies. The samples of visible and near-infrared spectroscopy at the wavelength of 450,900 nm were preprocessed using SWS, MSC and SNV. The experimental results indicate that the preprocessing using SWS and SNV and then modeling using PLS can achieve the most accurate estimation, with the correlation coefficient at 0.8492 and the root mean square error at 1.7216. Thus, the proposed approach can be widely used for winter wheat chlorophyll content analysis. PMID:27023550

  18. Development and Airborne Operation of a Compact Water Isotope Ratio Infrared Spectrometer

    NASA Technical Reports Server (NTRS)

    Iannone, Rosario Q.; Kassi, Samir; Jost, Hans-Juerg; Chenevier, Marc; Romanini, Daniele; Meijer, Harro A. J.; Dhaniyala, Suresh; Snels, Marcel; Kerstel, Erik R. T.

    2009-01-01

    A sensitive laser spectrometer, named IRIS (water isotope ratio infrared spectrometer), was developed for the in situ detection of the isotopic composition of water vapour in the upper troposphere and the lower stratosphere. Isotope ratio measurements can be used to quantify troposphere stratosphere exchange, and to study the water chemistry in the stratosphere. IRIS is based on the technique of optical feedback cavity-enhanced absorption spectroscopy. It uses a room temperature near-infrared laser, and does not require cryogenic cooling of laser or detectors. The instrument weighs 51 kg including its support structure. Airborne operation was demonstrated during three flights aboard the European M55-Geophysica stratospheric research aircraft, as part of the AMMA/SCOUT-03 (African Monsoon Multidisciplinary Analysis/Stratospheric Climate links with emphasis on the Upper Troposphere and lower stratosphere) campaign in Burkina Faso in August 2006. The data are discussed with reference to a Rayleigh distillation model. As expected, there is no indication of non-mass-dependent fractionation (also known as mass-independent fractionation) in the troposphere. Furthermore, improvements to the thermal management system and a move to a (cryogen-free) longer-wavelength laser source are discussed, which together should result in approximately two orders of magnitude improvement of the sensitivity

  19. Fiber-coupled high resolution infrared array spectrometer for the Kuiper Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Glenar, D. A.; Reuter, D.; Mumma, M. J.; Chin, G.; Wiedemann, G.; Jennings, D.

    1990-01-01

    A novel cryogenic grating spectrometer (FCAS) is being designed for observations of volatiles in cometary and planetary atmospheres, and in newly forming planetary systems. The instrument features two-dimensional detector arrays coupled to a high-dispersion echelle by infrared fibers, and will achieve a spectral resolving power of about 40,000. The primary observational platform for this instrument will be the Kuiper Airborne Observatory, but it will also be configured for use at ground-based observatories. Initially, the spectrometer will use a 58 x 62, 1- to 5-micron InSb array. Larger-format IR arrays and arrays of different composition, will later be incorporated as they become available. The instrument will be used in two modes. The first uses a large format IR array in the spectral image plane for the customary one-dimensional spectral-one-dimensional spatial coverage. In the second mode, a massive, coherent bundle of infrared transmitting ZrF4 fibers will be installed after the dispersive element, to reformat the two-dimensional array into an elongated one-dimensional array for wide spectral coverage, allowing multiple lines to be measured in a single integration with high sensitivity. The overall instrument design is discussed, and the system sensitivity is estimated.

  20. [UV, visible and infrared light. Which wavelengths produce oxidative stress in human skin?].

    PubMed

    Zastrow, L; Groth, N; Klein, F; Kockott, D; Lademann, J; Ferrero, L

    2009-04-01

    Experimental evidence suggests that the creation of free radicals--mainly reactive oxygen species (ROS)--is the common photobiological answer to the skin-sunlight interaction. The free radical action spectrum (wavelength dependency) for ultraviolet and visible light (280-700 nm) has been determined by quantitative ESR spectroscopy. Visible light produces around 50% of the total oxidative stress caused by sunlight. Reactive species like *O(-)(2), *OH and *CHR are generated by visible light. The amount of ROS correlates with the visible light intensity (illuminance). We demonstrated the creation of excess free radicals by near-infrared light (NIR, 700-1600 nm). Free radical generation does not depend exclusively on the NIR irradiance, but also on the NIR initiated skin temperature increase. The temperature dependence follows the physiological fever curve. Our results indicate that the complex biological system skin creates the same type of free radicals over the entire active solar spectrum. This general response will make it possible to define the beneficial or deleterious action of sunlight on human skin by introduction of a free radical threshold value.

  1. A filterless, visible-blind, narrow-band, and near-infrared photodetector with a gain

    NASA Astrophysics Data System (ADS)

    Shen, Liang; Zhang, Yang; Bai, Yang; Zheng, Xiaopeng; Wang, Qi; Huang, Jinsong

    2016-06-01

    In many applications of near-infrared (NIR) light detection, a band-pass filter is needed to exclude the noise caused by visible light. Here, we demonstrate a filterless, visible-blind, narrow-band NIR photodetector with a full-width at half-maximum of <50 nm for the response spectrum. These devices have a thick (>4 μm) nanocomposite absorbing layers made of polymer-fullerene:lead sulfide (PbS) quantum dots (QDs). The PbS QDs yield a photoconductive gain due to their hole-trapping effect, which effectively enhances both the responsivity and the visible rejection ratio of the external quantum efficiency by >10 fold compared to those without PbS QDs. Encouragingly, the inclusion of the PbS QDs does not increase the device noise. We directly measured a noise equivalent power (NEP) of 6.1 pW cm-2 at 890 nm, and a large linear dynamic range (LDR) over 11 orders of magnitude. The highly sensitive visible-blind NIR narrow-band photodetectors may find applications in biomedical engineering.

  2. Properties of Small Dark Features Observed in the Pure Near-Infrared and Visible Continua

    NASA Astrophysics Data System (ADS)

    Xu, Yan; Cao, Wenda; Ma, Jun; Hartkorn, Klaus; Jing, Ju; Denker, Carsten; Wang, Haimin

    2005-08-01

    High-resolution images in the visible and near-infrared (NIR) continua at around 1560 nm were obtained of solar active regions NOAA AR 10707 and AR 10486 with the Dunn Solar Telescope (DST) at the National Solar Observatory/Sacramento Peak (NSO/SP) on 2004 December 1 and 2 and 2003 October 29. The images were taken with the high-order adaptive optics (HOAO) system, and the spatial resolution was close to the diffraction limit of the 76 cm aperture DST in both wavelengths. For the 2004 December run, the NIR observations were made with a newly developed Lyot filter system, which was designed at the Center for Solar-Terrestrial Research (CSTR)/New Jersey Institute of Technology (NJIT). The filter has a bandpass of 2.5 Å that allows us to observe the pure NIR continuum at the opacity minimum. Our data show that all dark features in the NIR are also dark in the visible light. There is no evidence showing the existence of so-called dark faculae, i.e., faculae that have negative contrasts in the NIR but positive contrasts in the visible. The negative peak contrasts of these small pores are about 50% in the visible and 25% in the NIR, and their dimensions are in the range of 1"-4".

  3. Optical system of borescope for flame observation in visible (VIS) and infrared (NIR) part of light

    NASA Astrophysics Data System (ADS)

    Keprt, Jirí; Pospíšil, Ladislav; Hrabovský, Miroslav; Bartonek, Ludek

    2014-12-01

    To show flames in the visible and low infrared regions of radiation in the wavelength range from 400 nm to 2000 nm a design of optical systems technical borescope is presented. The proposed glass and technical parameters of the optical system correspond to the diameters of the lens elements and their distance of the borescope for VIS only. The correction lengths and distances of images are approximately the same and also correspond to the mechanical construction of the existing borescope for visible light. To record images in the wavelength range from 800 nm to 1000 nm it is possible to use the classic black-and-white cameras, e.g. OSCAR OS-458. Recording wavelengths in the range of 900 nm to 1700 nm allows, for example, InGaAs camera Bobcat 1.7-320.

  4. [Evaluation of Sugar Content of Huanghua Pear on Trees by Visible/Near Infrared Spectroscopy].

    PubMed

    Liu, Hui-jun; Ying, Yi-bin

    2015-11-01

    A method of ambient light correction was proposed to evaluate the sugar content of Huanghua pears on tree by visible/near infrared diffuse reflectance spectroscopy (Vis/NIRS). Due to strong interference of ambient light, it was difficult to collect the efficient spectral of pears on tree. In the field, covering the fruits with a bag blocking ambient light can get better results, but the efficiency is fairly low, the instrument corrections of dark and reference spectra may help to reduce the error of the model, however, the interference of the ambient light cannot be eliminated effectively. In order to reduce the effect of ambient light, a shutter was attached to the front of probe. When opening shutter, the spot spectrum were obtained, on which instrument light and ambient light acted at the same time. While closing shutter, background spectra were obtained, on which only ambient light acted, then the ambient light spectra was subtracted from spot spectra. Prediction models were built using data on tree (before and after ambient light correction) and after harvesting by partial least square (PLS). The results of the correlation coefficient (R) are 0.1, 0.69, 0.924; the root mean square error of prediction (SEP) are 0. 89°Brix, 0.42°Brix, 0.27°Brix; ratio of standard deviation (SD) to SEP (RPD) are 0.79, 1.69, 2.58, respectively. The results indicate that, method of background correction used in the experiment can reduce the effect of ambient lighting on spectral acquisition of Huanghua pears in field, efficiently. This method can be used to collect the visible/near infrared spectrum of fruits in field, and may give full play to visible/near-infrared spectroscopy in preharvest management and maturity testing of fruits in the field.

  5. Application of spectral derivative data in visible and near-infrared spectroscopy

    PubMed Central

    Dehghani, Hamid; Leblond, Frederic; Pogue, Brian W; Chauchard, Fabien

    2011-01-01

    The use of the spectral derivative method in visible and near-infrared optical spectroscopy is presented, whereby instead of using discrete measurements around several wavelengths, the difference between nearest neighbouring spectral measurements is utilized. The proposed technique is shown to be insensitive to the unknown tissue and fibre contact coupling coefficients providing substantially increased accuracy as compared to more conventional techniques. The self-calibrating nature of the spectral derivative techniques increases its robustness for both clinical and industrial applications, as is demonstrated based on simulated results as well as experimental data. PMID:20505221

  6. Standard reference for instrument response function in fluorescence lifetime measurements in visible and near infrared

    NASA Astrophysics Data System (ADS)

    Chib, Rahul; Shah, Sunil; Gryczynski, Zygmunt; Fudala, Rafal; Borejdo, Julian; Zelent, Bogumil; Corradini, Maria G.; Ludescher, Richard D.; Gryczynski, Ignacy

    2016-02-01

    Allura red (AR) fluorophore, a common dye in the food industry, displays a broad emission spectrum in water (visible-to-near infrared region of the electromagnetic spectrum) and has a remarkably short fluorescence lifetime of about 10 ps. This short lifetime does not depend on the emission (observation) wavelength. We examined time responses of AR fluorescence across emission wavelengths from 550 nm to 750 nm and found that it is an ideal candidate for impulse response functions in fluorescence lifetime measurements.

  7. Microcomputer Controlled MTF Measuring Equipment for Infra-red and Visible Wavelengths

    NASA Astrophysics Data System (ADS)

    Chauveau, J. P.; Perrin, J. C.

    1986-05-01

    An operational MTF measuring bench operating in both visible and infra-red regions is described. Measurements can be made at both room and climatic chamber temperatures. The basic mathematics for measuring the MTF from the edge spread function (ESF) or from the line spread function (LSF) are given. Optimal criteria for the measurement are derived taking into account the spatial sampling frequency and spectral resolution. The results obtained with standard lenses are compared with theoretical calculations. The microcomputer software has been optimized in order to give the result in form of graphs in a few seconds. If also provides options for measuring focal lengths or magnification, distortion, field curvature and transmission.

  8. Potential applications of digital, visible, and infrared data from geostationary environmental satellites

    NASA Technical Reports Server (NTRS)

    Miller, D. B.; Waters, M. P., III; Tarpley, J. D.; Green, R. N.; Dismachek, D. C.

    1977-01-01

    An hourly, digital data base from the Visible/Infrared Spin-Scan Radiometer (VISSR) instrument on the GOES-1 and SMS-2 geostationary satellites is described. Several examples of developmental applications of these quantitative digital data are presented. These include a review of recent attempts to develop products that are of use to meteorologists who provide services to aviation, agriculture, forestry, hydrology, oceanography, and climatology. The sample products include high resolution thermal gradients of land and ocean surfaces, thermal change analyses, fruit frost/freeze application, cloud-top altitude analysis, analysis of hurricane characteristics, and analyses of solar insolation.

  9. Describing the NPOESS Preparatory Project Visible/Infrared Imaging Radiometer Suite (VIIRS) Cloud Environmental Data Records

    NASA Astrophysics Data System (ADS)

    Hoffman, C.; Guenther, B.; Kilcoyne, H.; Mineart, G.; St. Germain, K.; Reed, B.

    2008-12-01

    The Visible/Infrared Imaging Radiometer Suite (VIIRS) is one of the instruments that make up the suite of sensors on the NPOESS Preparatory Project (NPP) scheduled to launch in 2010. VIIRS will produce seven Environmental Data Records (EDRs) describing cloud properties. The VIIRS Cloud EDRs include the Cloud Optical Thickness (COT), Cloud Effective Particle Size Parameter (CEPS), Cloud Top Pressure (CTP), Cloud Top Height (CTH), Cloud Top Temperature (CTT), Cloud Cover/Layers (CCL), and Cloud Base Height (CBH). This paper will describe the VIIRS algorithms used to generate these EDRs and provide a current estimate of performance based on pre-Launch test data.

  10. Concept development for the ITER equatorial port visible/infrared wide angle viewing systema)

    NASA Astrophysics Data System (ADS)

    Reichle, R.; Beaumont, B.; Boilson, D.; Bouhamou, R.; Direz, M.-F.; Encheva, A.; Henderson, M.; Huxford, R.; Kazarian, F.; Lamalle, Ph.; Lisgo, S.; Mitteau, R.; Patel, K. M.; Pitcher, C. S.; Pitts, R. A.; Prakash, A.; Raffray, R.; Schunke, B.; Snipes, J.; Diaz, A. Suarez; Udintsev, V. S.; Walker, C.; Walsh, M.

    2012-10-01

    The ITER equatorial port visible/infrared wide angle viewing system concept is developed from the measurement requirements. The proposed solution situates 4 viewing systems in the equatorial ports 3, 9, 12, and 17 with 4 views each (looking at the upper target, the inner divertor, and tangentially left and right). This gives sufficient coverage. The spatial resolution of the divertor system is 2 times higher than the other views. For compensation of vacuum-vessel movements, an optical hinge concept is proposed. Compactness and low neutron streaming is achieved by orienting port plug doglegs horizontally. Calibration methods, risks, and R&D topics are outlined.

  11. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.

    PubMed

    Holick, Michael F

    2016-03-01

    Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation. PMID:26977036

  12. Composition, mineralogy, and porosity of multiple asteroid systems from visible and near-infrared spectral data

    NASA Astrophysics Data System (ADS)

    Lindsay, S. S.; Marchis, F.; Emery, J. P.; Enriquez, J. E.; Assafin, M.

    2015-02-01

    We aim to provide a taxonomic and compositional characterization of Multiple Asteroid Systems (MASs) located in the main belt (MB) using visible (0.45-0.85 μm) and near-infrared (0.7-2.5 μm) spectral data of 42 MB MASs. The compositional and mineralogical analysis is applied to determine meteorite analogs for the MASs, which, in turn, are applied to the MAS density measurements of Marchis et al. (Marchis et al. [2012]. Icarus 221, 1130-1161) to estimate the porosity of the systems. The macroporosities are used to evaluate the primary MAS formation hypotheses. Our spectral survey consists of visible and near-infrared spectral data. The visible observing campaign includes 25 MASs obtained using the Southern Astrophysical Research (SOAR) telescope with the Goodman High Throughput Spectrometer. The infrared observing campaign includes 34 MASs obtained using the NASA Infrared Telescope Facility (IRTF) with the SpeX spectragraph. For completeness, both visible and NIR data sets are supplemented with publicly available data, and the data sets are combined where possible. The MASs are classified using the Bus-DeMeo taxonomic system. In order to determine mineralogy and meteorite analog, we perform a NIR spectral band parameter analysis using a new analysis routine, the Spectral Analysis Routine for Asteroids (SARA). The SARA routine determines band centers, areas, and depths by utilizing the diagnostic absorption features near 1- and 2-μm due to Fe2+ crystal field transitions in olivine + pyroxene and pyroxene, respectively. The band parameter analysis provides the Gaffey subtype for the S-complex MASs; the relative abundance olivine-to-pyroxene ratio; and olivine and pyroxene modal abundances for S-complex and V-type MASs. This mineralogical information is then applied to determine meteorite analogs. Through applying calibration studies, we are able to determine the H, L, and LL meteorite analogs for 15 MASs with ordinary chondrite-like (OC) mineralogies. We observe an

  13. Visible/Near-Infrared Hyperspectral Sensing of Solids under Controlled Environmental Conditions

    SciTech Connect

    Bernacki, Bruce E.; Anheier, Norman C.; Mendoza, Albert; Fritz, Brad G.; Johnson, Timothy J.

    2011-06-01

    We describe the use of a wind tunnel for conducting controlled passive hyperspectral imaging experiments. Passive techniques are potentially useful for detecting explosives, solid-phase chemicals and other materials of interest from a distance so as to provide operator safety. The Pacific Northwest National Laboratory operates a wind tunnel facility that can generate and circulate artificial atmospheres to control lighting, humidity, temperature, aerosol burdens, and obscurants. We will present recent results describing optimized sensing of solids over tens of meters distance using both visible and near-infrared cameras, as well as the effects of certain environmental parameters on data retrieval.

  14. Visible and infrared detector developments supported by the European Space Agency

    NASA Astrophysics Data System (ADS)

    Nelms, N.; Minoglou, K.; Voland, C.; Levillain, Y.; Meynart, R.; Bezy, J.-L.; Duvet, L.; Zahir, M.; Leone, B.; Ciapponi, A.; Crouzet, P.-E.

    2015-10-01

    Remote sensing is a priority activity for the European Space Agency and detector performance is a crucial factor in determining how well this role is performed. Consequently, the Agency has a strong interest in continuous improvement of both detector capabilities and availability within Europe. To this end, ESA maintains a number of strategic detector development plans combining both technology-push and technology-pull. The visible and infrared wavebands are of particular interest for remote sensing activities and this paper sets out the requirements for current and future missions and presents details of the Agency's current and planned detector developments.

  15. Improving Atmospheric Correction for Visible/Short Wave Infrared (VSWIR) Imaging Spectrometers with Iterative Fitting of Absorption By Three Phases of Water

    NASA Astrophysics Data System (ADS)

    Pennington, E. A.; Thompson, D. R.; Green, R. O.; Gao, B. C.

    2014-12-01

    Airborne imaging spectrometers like the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) offer valuable insight into the Earth's terrestrial and ocean ecosystems, mineralogy, and land use. Estimating surface reflectance requires accounting for atmospheric absorption, which is sensitive to the local abundance of water vapor. Analysts typically estimate water vapor concentrations using the depths of absorption features, which can be inaccurate by up to 50% over surface features containing liquid water or ice. This can bias the retrieved water vapor maps and create atmospheric artifacts in reflectance spectra. A new retrieval method offers significant accuracy improvements over plant canopies or ice by estimating the path lengths of all three phases of water simultaneously, adjusting absorptions to best fit the measurement over a broader spectral interval. This paper assesses the remaining sources of error for the three-phase retrieval technique. We analyze retrievals for synthetic data when the 940 and 1140 nm wavelength features are fitted, for initial vapor path estimates ranging from 0 to ±50% accuracy. These tests indicate that most error comes from inaccuracy in the initial path estimate used to obtain vapor absorption coefficients. We evaluate a modified algorithm that uses multiple iterations to refine this estimate. Error is found to approach a constant value, demonstrating improved robustness to initialization conditions. We also assess the new iterative method using corrected AVIRIS data over various environments. The iterative method yields significantly better water vapor maps, reducing spurious correlations between vegetation canopy water and vapor estimates. The new iterative method offers accuracy improvements over traditional Visible/Short Wave Infrared (VSWIR) atmospheric correction methods, at modest computational cost.

  16. Visible and Infra-red Light Emission in Boron-Doped Wurtzite Silicon Nanowires

    PubMed Central

    Fabbri, Filippo; Rotunno, Enzo; Lazzarini, Laura; Fukata, Naoki; Salviati, Giancarlo

    2014-01-01

    Silicon, the mainstay semiconductor in microelectronic circuitry, is considered unsuitable for optoelectronic applications owing to its indirect electronic band gap, which limits its efficiency as a light emitter. Here we show the light emission properties of boron-doped wurtzite silicon nanowires measured by cathodoluminescence spectroscopy at room temperature. A visible emission, peaked above 1.5 eV, and a near infra-red emission at 0.8 eV correlate respectively to the direct transition at the Γ point and to the indirect band-gap of wurtzite silicon. We find additional intense emissions due to boron intra-gap states in the short wavelength infra-red range. We present the evolution of the light emission properties as function of the boron doping concentration and the growth temperature. PMID:24398782

  17. Definitions in use by the visible and near-infrared, and thermal working groups

    NASA Technical Reports Server (NTRS)

    Bruegge, Carol J.; Miller, ED; Martin, Bob; Kieffer, Hugh H.; Palmer, James M.

    1992-01-01

    The Calibration Advisory Panel (CAP) is composed of calibration experts from each of the Earth Observing System (EOS) instruments, science investigation, and cross-calibration teams. These members come from a variety of institutions and backgrounds. In order to facilitate an exchange of ideas, and assure a common basis for communication, it was desirable to assemble this list of definitions. These definitions were developed for use by the visible and near-infrared working group, and the thermal infrared working group. Where necessary or appropriate, deviations from these for specific instruments or other sensor types are given in the individual calibration plans. The definitions contained in this document are derived, wherever possible, from definitions accepted by international and national metrological commissions including the United States National Institute of Standards and Technology (NIST), the International Bureau of Weights and Measures (BIPM), the International Electrotechnical Commission (IEC), the International Organization for Standardization (ISO), and the International Organization of Legal Metrology (OIML).

  18. Visible and infra-red light emission in boron-doped wurtzite silicon nanowires.

    PubMed

    Fabbri, Filippo; Rotunno, Enzo; Lazzarini, Laura; Fukata, Naoki; Salviati, Giancarlo

    2014-01-08

    Silicon, the mainstay semiconductor in microelectronic circuitry, is considered unsuitable for optoelectronic applications owing to its indirect electronic band gap, which limits its efficiency as a light emitter. Here we show the light emission properties of boron-doped wurtzite silicon nanowires measured by cathodoluminescence spectroscopy at room temperature. A visible emission, peaked above 1.5 eV, and a near infra-red emission at 0.8 eV correlate respectively to the direct transition at the Γ point and to the indirect band-gap of wurtzite silicon. We find additional intense emissions due to boron intra-gap states in the short wavelength infra-red range. We present the evolution of the light emission properties as function of the boron doping concentration and the growth temperature.

  19. Nickel, argon and cobalt in the infrared spectrum of SN1987A - The core becomes visible

    NASA Technical Reports Server (NTRS)

    Rank, D. M.; Pinto, P. A.; Woosley, S. E.; Bregman, J. D.; Witteborn, F. C.

    1988-01-01

    Infrared spectra of supernova 1987A taken in April and November 1987 are presented, showing two distinctly different stages in the evolution of the expanding gas shell. The optical and infrared spectrum in April originated from the hydrogen envelope and show weak hydrogen lines rising above a 5,000-K photospheric continuum. The November spectrum was dominated by strong emission lines from heavy elements as well as many lines from highly excited levels of hydrogen, with peak flux levels in the lines at or slightly above the level of the continuum in April. It is concluded that the inner regions of the supernova were just becoming visible in early 1988. It is expected that these regions contain heavy elements produced by advanced nuclear burning stages in the progenitor star and in the shock wave that ejected all material external to the iron core.

  20. Cloud detection performance of spaceborne visible-to-infrared multispectral imagers.

    PubMed

    Nakajima, Takashi Y; Tsuchiya, Takumi; Ishida, Haruma; Matsui, Takashi N; Shimoda, Haruhisa

    2011-06-10

    We investigate the cloud detection efficiency of existing and future spaceborne visible-to-infrared imagers, focusing on several threshold tests for cloud detection over different types of ground surfaces, namely, the ocean, desert, vegetation, semibare land, and cryosphere. In this investigation, we used the CLoud and Aerosol Unbiased Decision Intellectual Algorithm (CLAUDIA), which was developed for unbiased cloud detection. It was revealed that imagers with fewer bands than the Moderate Resolution Imaging Spectroradiometer tend to have cloudy shifts. An imager without any infrared bands could yield cloudy shifts up to 17% over the ocean. To avoid false recognition of Sun glint as clouds, the 0.905 and 0.935  μm bands are needed in addition to the infrared bands. In reflectance ratio tests, the 0.87 and 1.6  μm bands can effectively distinguish clouds from desert. In the case of desert, thermal-infrared bands are ineffective when the desert surface temperature is low during winter. The 3.9 and 11  μm bands are critical for distinguishing between clear and cloudy pixels over snow-/ice-covered areas. The results and discussions of this research can guide CLAUDIA users in the optimization of thresholds. Here, we propose a virtual imager called the cloud detection imager, which has seven or eight bands for efficient cloud detection.

  1. Cloud detection performance of spaceborne visible-to-infrared multispectral imagers.

    PubMed

    Nakajima, Takashi Y; Tsuchiya, Takumi; Ishida, Haruma; Matsui, Takashi N; Shimoda, Haruhisa

    2011-06-10

    We investigate the cloud detection efficiency of existing and future spaceborne visible-to-infrared imagers, focusing on several threshold tests for cloud detection over different types of ground surfaces, namely, the ocean, desert, vegetation, semibare land, and cryosphere. In this investigation, we used the CLoud and Aerosol Unbiased Decision Intellectual Algorithm (CLAUDIA), which was developed for unbiased cloud detection. It was revealed that imagers with fewer bands than the Moderate Resolution Imaging Spectroradiometer tend to have cloudy shifts. An imager without any infrared bands could yield cloudy shifts up to 17% over the ocean. To avoid false recognition of Sun glint as clouds, the 0.905 and 0.935  μm bands are needed in addition to the infrared bands. In reflectance ratio tests, the 0.87 and 1.6  μm bands can effectively distinguish clouds from desert. In the case of desert, thermal-infrared bands are ineffective when the desert surface temperature is low during winter. The 3.9 and 11  μm bands are critical for distinguishing between clear and cloudy pixels over snow-/ice-covered areas. The results and discussions of this research can guide CLAUDIA users in the optimization of thresholds. Here, we propose a virtual imager called the cloud detection imager, which has seven or eight bands for efficient cloud detection. PMID:21673762

  2. Light-Harvesting Photosensitizers for Photodynamic Inactivation of Bacteria under Both Visible and Near-Infrared Excitations.

    PubMed

    Hu, Bo; Cao, Xian; Ahmadov, Ms Tevhide Ozkaya; Ding, Rui; Tang, Hong; Zhang, Peng

    2016-04-01

    We report a hybrid singlet oxygen production system, where strong resonance coupling between plasmonic nanoparticles and photosensitizing molecules results in exceptionally high singlet oxygen production under both visible light and near-infrared light excitation, even for the photosensitizing molecules without near-infrared absorption. The light-harvesting property of the plasmon-photosensitizer hybrids leads to an enhanced, broad-spectrum photodynamic inactivation of bacteria under a wide range of excitations, including that with near-infrared light.

  3. Thermal Infrared Airborne Field Studies: Applications to the Mars Global Surveyor Thermal Emission Spectrometer

    NASA Astrophysics Data System (ADS)

    Herr, K.; Kirkland, L.; Keim, E.; Hackwell, J.

    2002-12-01

    A primary goal of the Mars exploration program is to reconnoiter the planet from orbit using infrared remote sensing. Currently the Global Surveyor Thermal Emission Spectrometer (TES) and the 2001 Mars Odyssey 9-band radiometer THEMIS provide this capability. Landing site selection and modeling of the geologic and climate history depend on accurate interpretations of these data sets. Interpretations use terrestrial analog remote sensing and laboratory studies. Until recently, there have been no airborne thermal infrared spectrometer ("hyspectral") data sets available to NASA researchers that are comparable to TES. As a result, studies relied on airborne multi-channel radiometer ("multispectral") measurements (e.g. TIMS, MASTER). A radiometer has the advantage that measurement of broad bands makes it easier to measure with higher sensitivity. However, radiometers lack the spectral resolution to investigate details of spectral signatures. This gap may be partially addressed using field samples collected and measured in the laboratory. However, that leaves questions unanswered about the field environment and potentially leaves important complicating issues undiscovered. Two questions that haunt thermal infrared remote sensing investigations of Mars are: (1) If a mineral is not detected in a given data set, how definitively should we state that it is not there? (2) When does the method provide quantitative mineral mapping? In order to address these questions, we began collaborating with Department of Defense (DoD) oriented researchers and drawing on the unique instrumentation they developed. Both Mars and DoD researchers have a common need to identify materials without benefit of ground truth. Such collaborations provide a fresh perspective as well as unique data. Our work addresses uncertainties in stand-off identification of solid phase surface materials when the identification must proceed without benefit of ground truth. We will report on the results applied to TES

  4. Mapping wetland species and the impact of oil from the Deep Horizon using the Airborne/Visible Imaging Spectrometer and Multiple Endmember Spectral Mixture Analysis

    NASA Astrophysics Data System (ADS)

    Roberts, D. A.; Beland, M.; Kokaly, R. F.; Couvillion, B.; Ustin, S.; Peterson, S.

    2011-12-01

    Between April 20, 2010 and July 15, 2010 an estimated 4.4 million barrels of oil leaked from the Maconda well, making the Deep Horizon oil spill the largest in US history. In response to a need to determine the distribution of wetland plant species and quantify their condition prior to, during and after oil reached the shore, the Airborne/Visible Infrared Imaging Spectrometer (AVIRIS) was deployed multiple times in the gulf on high altitude and low altitude airborne platforms. Significant research questions included 1) What is the distribution of key wetland species in the impacted area?; 2) which areas were impacted by oil, when and to what extent?; 3) how much oil must be present to be detected in various cover types? and 4) which wetland species are more sensitive to oil? In an effort to answer some of these questions, we applied Multiple Endmember Spectral Mixture Analysis (MESMA) to AVIRIS data acquired prior to significant impacts in May, 2010 and after oil had reached wetlands in late summer and fall, 2010. Reference polygons for species dominants were located on the images and used to build a spectral library for all dominant wetland species and surface types. This spectral library was augmented by field spectra, acquired using a contact probe for senesced plants materials and beach sands. Spectra of heavily oiled surfaces were identified using the Hydrocarbon Index to identify potential oil endmembers and the Cellulose Absorption Index to discriminate oil from Non-photosynthetic Vegetation (NPV). Wetland species and cover fractions for Green Vegetation (GV), NPV, soils/beaches, oil and water were mapped using MESMA applied to images acquired in the Birds Foot Delta, Chandeleur Islands and Barataria Bay. Species maps, showing dominant species such as Phragmites australis, Spartina alternifolia and S. patens proved to be accurate. OIl was mapped along coastal areas of Barataria Bay, expressed as high oil fractions. However, significant confusion was also

  5. Detection of multiple stresses in Scots pine growing at post-mining sites using visible to near-infrared spectroscopy.

    PubMed

    Zuzana, Lhotáková; Lukáš, Brodský; Lucie, Kupková; Veronika, Kopačková; Markéta, Potůčková; Jan, Mišurec; Aleš, Klement; Monika, Kovářová; Jana, Albrechtová

    2013-10-01

    Heavy metal contamination, low pH and high substrate heterogeneity are multiple stress factors that often occur at the post-mining sites and make difficult the biological reclamation. Efficient tools for detection of the status of reclaimed vegetation at post-mining sites are needed. We tested the potential of visible to near-infrared (VNIR) spectroscopy to detect multiple stresses in Scots pine (Pinus sylvestris L.) at acidic substrates rich in As. The needle chemical traits (chlorophyll a + b - Cab; carotenoids - Car; Car/Cab; relative water content - RWC; soluble phenolics; lignin contents) were tested for sensitivity to different soil conditions of post-mining sites. For Scots pine growing on degraded substrates, at least three non-specific stress indicators (RWC, photosynthetic pigments and phenolics) are required to achieve good site separability corresponding to the stress load. We constructed and validated empirical models of selected needle chemical traits using VNIR spectroscopy: calibration of Cab (R(2) = 0.97, RMSE = 0.17 mg g(-1)), RWC (R(2) = 0.88, RMSE = 1.41 mg g(-1)), Car (R(2) = 0.66, RMSE = 0.08 mg g(-1)), phenolics (R(2) = 0.64, RMSE = 23.01 mg g(-1)) and lignin (R(2) = 0.45, RMSE = 3.32 mg g(-1)). The reflectance data yielded comparable site separability with the separability calculated from the laboratory data. The presented approach has potential for large-scale monitoring of Scots pine status, thus, assessment of reclamation quality in post-mining regions using air-born or satellite hyperspectral data. PMID:24108147

  6. Identification of pesticide varieties by testing microalgae using Visible/Near Infrared Hyperspectral Imaging technology

    NASA Astrophysics Data System (ADS)

    Shao, Yongni; Jiang, Linjun; Zhou, Hong; Pan, Jian; He, Yong

    2016-04-01

    In our study, the feasibility of using visible/near infrared hyperspectral imaging technology to detect the changes of the internal components of Chlorella pyrenoidosa so as to determine the varieties of pesticides (such as butachlor, atrazine and glyphosate) at three concentrations (0.6 mg/L, 3 mg/L, 15 mg/L) was investigated. Three models (partial least squares discriminant analysis combined with full wavelengths, FW-PLSDA; partial least squares discriminant analysis combined with competitive adaptive reweighted sampling algorithm, CARS-PLSDA; linear discrimination analysis combined with regression coefficients, RC-LDA) were built by the hyperspectral data of Chlorella pyrenoidosa to find which model can produce the most optimal result. The RC-LDA model, which achieved an average correct classification rate of 97.0% was more superior than FW-PLSDA (72.2%) and CARS-PLSDA (84.0%), and it proved that visible/near infrared hyperspectral imaging could be a rapid and reliable technique to identify pesticide varieties. It also proved that microalgae can be a very promising medium to indicate characteristics of pesticides.

  7. Calibration of visible and near infrared spectrums for measuring freshness of vegetables

    NASA Astrophysics Data System (ADS)

    Abdullah, Faisal; Mat Jafri, M. Z.; Jaafar, M. S.; Wong, C. J.

    2008-03-01

    A new nondestructive methods based on optical properties at multiple wavelengths is being applied to measure the freshness of some vegetables. The principle of this method is to determine the absorbance and the reflectance of a sample in visible and near infrared region. When a light beam is illuminated upon a piece of vegetable sample, the majority of the lights penetrate into the sample tissue. Upon entering the tissue, photons scatter in different directions. Some are absorbed, some pass-through to the whole sample and emerge from the opposite side, and some scatter back and reemerge from the region adjacent to the incident center. While the absorption is related to certain chemical constituent of the sample, scattering is influenced by the density, compositions, cells and intercellular structures of samples and therefore can be useful for measuring samples freshness. Our objectives are to investigate the spectral behavior of some vegetables and to develop an algorithm for a non-destructive freshness sensor system using visible and near infrared light sources. The preliminary results of the study showed that the freshness of green mustard leaf and onion using a red (λ = 633 nm) and green (λ = 808 nm) light sources were closely related.

  8. Calibration of Visible and Near-infrared Imaging Spectrometer (VNIS) on lunar surface

    NASA Astrophysics Data System (ADS)

    Xu, Rui; Lv, Gang; Ma, Yan-hua; Wang, Jianyu

    2014-11-01

    Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the scientific payloads mounted on "Yutu" rover in Chang'e 3 lunar exploration project. The VNIS is composed with a visible and near-infrared (0.45-0.95 μm) spectral imager and a short waveband (0.9-2.4 μm) spectrometer on basis of Acousto-Optic Tunable Filter. According to the in-situ analysis, a calibration unit was also equipped for high precisely spectral radiance and reflectance inversion by using solar as standard calibration source. The calibration unit was driven by lightweight ultrasonic motor, and it could be located on three fixed position including detection (full-opened), calibration (horizontal) and dust-proof (closed). In this paper, the principle of VNIS, especially calibration unit was described firstly. Then, radiometric correction algorithms on lunar surface based on standard solar spectral irradiance were expounded. Through the analysis of VNIS scientific data, the spectral radiance and reflectance curves of detection area were shown in the end.

  9. Identification of pesticide varieties by testing microalgae using Visible/Near Infrared Hyperspectral Imaging technology

    PubMed Central

    Shao, Yongni; Jiang, Linjun; Zhou, Hong; Pan, Jian; He, Yong

    2016-01-01

    In our study, the feasibility of using visible/near infrared hyperspectral imaging technology to detect the changes of the internal components of Chlorella pyrenoidosa so as to determine the varieties of pesticides (such as butachlor, atrazine and glyphosate) at three concentrations (0.6 mg/L, 3 mg/L, 15 mg/L) was investigated. Three models (partial least squares discriminant analysis combined with full wavelengths, FW-PLSDA; partial least squares discriminant analysis combined with competitive adaptive reweighted sampling algorithm, CARS-PLSDA; linear discrimination analysis combined with regression coefficients, RC-LDA) were built by the hyperspectral data of Chlorella pyrenoidosa to find which model can produce the most optimal result. The RC-LDA model, which achieved an average correct classification rate of 97.0% was more superior than FW-PLSDA (72.2%) and CARS-PLSDA (84.0%), and it proved that visible/near infrared hyperspectral imaging could be a rapid and reliable technique to identify pesticide varieties. It also proved that microalgae can be a very promising medium to indicate characteristics of pesticides. PMID:27071456

  10. Wide-angle ITER-prototype tangential infrared and visible viewing system for DIII-D

    SciTech Connect

    Lasnier, C. J. Allen, S. L.; Ellis, R. E.; Fenstermacher, M. E.; McLean, A. G.; Meyer, W. H.; Morris, K.; Seppala, L. G.; Crabtree, K.; Van Zeeland, M. A.

    2014-11-15

    An imaging system with a wide-angle tangential view of the full poloidal cross-section of the tokamak in simultaneous infrared and visible light has been installed on DIII-D. The optical train includes three polished stainless steel mirrors in vacuum, which view the tokamak through an aperture in the first mirror, similar to the design concept proposed for ITER. A dichroic beam splitter outside the vacuum separates visible and infrared (IR) light. Spatial calibration is accomplished by warping a CAD-rendered image to align with landmarks in a data image. The IR camera provides scrape-off layer heat flux profile deposition features in diverted and inner-wall-limited plasmas, such as heat flux reduction in pumped radiative divertor shots. Demonstration of the system to date includes observation of fast-ion losses to the outer wall during neutral beam injection, and shows reduced peak wall heat loading with disruption mitigation by injection of a massive gas puff.

  11. Wide-angle ITER-prototype tangential infrared and visible viewing system for DIII-D.

    PubMed

    Lasnier, C J; Allen, S L; Ellis, R E; Fenstermacher, M E; McLean, A G; Meyer, W H; Morris, K; Seppala, L G; Crabtree, K; Van Zeeland, M A

    2014-11-01

    An imaging system with a wide-angle tangential view of the full poloidal cross-section of the tokamak in simultaneous infrared and visible light has been installed on DIII-D. The optical train includes three polished stainless steel mirrors in vacuum, which view the tokamak through an aperture in the first mirror, similar to the design concept proposed for ITER. A dichroic beam splitter outside the vacuum separates visible and infrared (IR) light. Spatial calibration is accomplished by warping a CAD-rendered image to align with landmarks in a data image. The IR camera provides scrape-off layer heat flux profile deposition features in diverted and inner-wall-limited plasmas, such as heat flux reduction in pumped radiative divertor shots. Demonstration of the system to date includes observation of fast-ion losses to the outer wall during neutral beam injection, and shows reduced peak wall heat loading with disruption mitigation by injection of a massive gas puff.

  12. [Design of airborne dual channel ultraviolet-visible imaging spectrometer with large field of view, wide spectrum, and high resolution].

    PubMed

    Hao, Ai-Hua; Hu, Bing-Liang; Bai, Jia-Guang; Li, Li-Bo; Yu, Tao; Li, Si-Yuan

    2013-12-01

    The ultraviolet-visible (UV-Vis 200-500 nm) imaging spectrometer is an important part of space remote sensing. Based on special requirements and practical application of the airborne UV-VIS spectrometer, a kind of scanning imaging spectrometer using area array CCD is proposed, which can meet the application requirements of large field of view, wide spectrum and high resolution. It overcomes low spatial resolution of traditional line array CCD scanning imaging spectrometer, and limited field of view of the pushbroom imaging spectrometer. In addition, dual channel was designed to reduce stray light. 400-500 nm band includes two order spectrum for 200-250 nm band, and variation of radiance from earth between the shorter wavelength (<290 nm) and the longer wavelength (>310 nm) is above three orders of magnitude. In the structure design of the system, the imaging spectrometer is composed of a two-mirror concentric telescope and two Czerny-Turner plane grating imaging spectrometers. The whole system doesn't use any additional optical elements in addition to spherical mirrors. The whole system has the advantage of simple structure, excellent performance, and very good feasibility. The modulation transfer function value of full spectrum and full field of view is above 0.6.

  13. Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum.

    PubMed

    Kresnaraman, Brahmastro; Deguchi, Daisuke; Takahashi, Tomokazu; Mekada, Yoshito; Ide, Ichiro; Murase, Hiroshi

    2016-01-01

    During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA). The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations. PMID:27110781

  14. Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum †

    PubMed Central

    Kresnaraman, Brahmastro; Deguchi, Daisuke; Takahashi, Tomokazu; Mekada, Yoshito; Ide, Ichiro; Murase, Hiroshi

    2016-01-01

    During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA). The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations. PMID:27110781

  15. The design and synthesis of heterostructured quantum dots with dual emission in the visible and infrared

    SciTech Connect

    Lin, Qianglu; Makarov, Nikolay S.; Koh, Weon-kyu; Velizhanin, Kirill A.; Cirloganu, Claudiu M.; Luo, Hongmei; Klimov, Victor I.; Pietryga, Jeffrey M.

    2014-11-26

    The unique optical properties exhibited by visible emitting core/shell quantum dots with especially thick shells are the focus of widespread study, but have yet to be realized in infrared (IR) -active nanostructures. We apply an effective-mass model to identify PbSe/CdSe core/shell quantum dots as a promising system for achieving this goal. We then synthesize colloidal PbSe/CdSe quantum dots with shell thicknesses of up to 4 nm that exhibit unusually slow hole intra-band relaxation from shell to core states, as evidenced by the emergence of dual emission, i.e., IR photoluminescence from the PbSe core observed simultaneously with visible emission from the CdSe shell. In addition to the large shell thickness, the development of slowed intraband relaxation is facilitated by the existence of a sharp core-shell interface without discernible alloying. Growth of thick shells without interfacial alloying or incidental formation of homogenous CdSe nanocrystals was accomplished using insights attained via a systematic study of the dynamics of the cation-exchange synthesis of both PbSe/CdSe as well as the related system PbS/CdS. Finally, we show that the efficiency of the visible photoluminescence can be greatly enhanced by inorganic passivation.

  16. Bio-empirical mode decomposition: visible and infrared fusion using biologically inspired empirical mode decomposition

    NASA Astrophysics Data System (ADS)

    Sissinto, Paterne; Ladeji-Osias, Jumoke

    2013-07-01

    Bio-EMD, a biologically inspired fusion of visible and infrared (IR) images based on empirical mode decomposition (EMD) and color opponent processing, is introduced. First, registered visible and IR captures of the same scene are decomposed into intrinsic mode functions (IMFs) through EMD. The fused image is then generated by an intuitive opponent processing the source IMFs. The resulting image is evaluated based on the amount of information transferred from the two input images, the clarity of details, the vividness of depictions, and range of meaningful differences in lightness and chromaticity. We show that this opponent processing-based technique outperformed other algorithms based on pixel intensity and multiscale techniques. Additionally, Bio-EMD transferred twice the information to the fused image compared to other methods, providing a higher level of sharpness, more natural-looking colors, and similar contrast levels. These results were obtained prior to optimization of color opponent processing filters. The Bio-EMD algorithm has potential applicability in multisensor fusion covering visible bands, forensics, medical imaging, remote sensing, natural resources management, etc.

  17. Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum.

    PubMed

    Kresnaraman, Brahmastro; Deguchi, Daisuke; Takahashi, Tomokazu; Mekada, Yoshito; Ide, Ichiro; Murase, Hiroshi

    2016-04-21

    During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA). The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations.

  18. The design and synthesis of heterostructured quantum dots with dual emission in the visible and infrared

    DOE PAGES

    Lin, Qianglu; Makarov, Nikolay S.; Koh, Weon-kyu; Velizhanin, Kirill A.; Cirloganu, Claudiu M.; Luo, Hongmei; Klimov, Victor I.; Pietryga, Jeffrey M.

    2014-11-26

    The unique optical properties exhibited by visible emitting core/shell quantum dots with especially thick shells are the focus of widespread study, but have yet to be realized in infrared (IR) -active nanostructures. We apply an effective-mass model to identify PbSe/CdSe core/shell quantum dots as a promising system for achieving this goal. We then synthesize colloidal PbSe/CdSe quantum dots with shell thicknesses of up to 4 nm that exhibit unusually slow hole intra-band relaxation from shell to core states, as evidenced by the emergence of dual emission, i.e., IR photoluminescence from the PbSe core observed simultaneously with visible emission from themore » CdSe shell. In addition to the large shell thickness, the development of slowed intraband relaxation is facilitated by the existence of a sharp core-shell interface without discernible alloying. Growth of thick shells without interfacial alloying or incidental formation of homogenous CdSe nanocrystals was accomplished using insights attained via a systematic study of the dynamics of the cation-exchange synthesis of both PbSe/CdSe as well as the related system PbS/CdS. Finally, we show that the efficiency of the visible photoluminescence can be greatly enhanced by inorganic passivation.« less

  19. Temperature and emissivity separation and mineral mapping based on airborne TASI hyperspectral thermal infrared data

    NASA Astrophysics Data System (ADS)

    Cui, Jing; Yan, Bokun; Dong, Xinfeng; Zhang, Shimin; Zhang, Jingfa; Tian, Feng; Wang, Runsheng

    2015-08-01

    Thermal infrared remote sensing (8-12 μm) (TIR) has great potential for geologic remote sensing studies. TIR has been successfully used for terrestrial and planetary geologic studies to map surface materials. However, the complexity of the physics and the lack of hyperspectral data make the studies under-investigated. A new generation of commercial hyperspectral infrared sensors, known as Thermal Airborne Spectrographic Imager (TASI), was used for image analysis and mineral mapping in this study. In this paper, a combined method integrating normalized emissivity method (NEM), ratio algorithm (RATIO) and maximum-minimum apparent emissivity difference (MMD), being applied in multispectral data, has been modified and used to determine whether this method is suitable for retrieving emissivity from TASI hyperspectral data. MODTRAN 4 has been used for the atmospheric correction. The retrieved emissivity spectra matched well with the field measured spectra except for bands 1, 2, and 32. Quartz, calcite, diopside/hedenbergite, hornblende and microcline have been mapped by the emissivity image. Mineral mapping results agree with the dominant minerals identified by laboratory X-ray powder diffraction and spectroscopic analyses of field samples. Both of the results indicated that the atmospheric correction method and the combined temperature-emissivitiy method are suitable for TASI image. Carbonate skarnization was first found in the study area by the spatial extent of diopside. Chemical analyses of the skarn samples determined that the Au content was 0.32-1.74 g/t, with an average Au content of 0.73 g/t. This information provides an important resource for prospecting for skarn type gold deposits. It is also suggested that TASI is suitable for prospect and deposit scale exploration.

  20. Scanning infrared remote sensing system for identification, visualization, and quantification of airborne pollutants

    NASA Astrophysics Data System (ADS)

    Harig, Roland; Matz, Gerhard; Rusch, Peter

    2002-02-01

    Remote sensing by Fourier-transform infrared (FTIR) spectrometry allows detection, identification, and quantification of airborne pollutants. In the case of leaks in pipelines or leaks in chemical plants, chemical accidents, terrorism, or war, hazardous compounds are often released into the atmosphere. Various Fourier-transform infrared spectrometers have been developed for the remote detection and identification of hazardous clouds. However, for the localization of a leak and a complete assessment of the situation in the case of the release of a hazardous cloud, information about the position and the size of a cloud is essential. Therefore, an imaging passive remote sensing system comprised of an interferometer (Bruker OPAG 22), a data acquisition, processing, and control system with a digital signal processor (FTIR DSP), an azimuth-elevation-scanning mirror, a video system with a DSP, and a personal computer has been developed. The FTIR DSP system controls the scanning mirror, collects the interferograms, and performs the Fourier transformation. The spectra are transferred to a personal computer and analyzed by a real-time identification algorithm that does not require background spectra for the analysis. The results are visualized by a video image, overlaid by false color images. For each target compound of a spectral library, images of the coefficient of correlation, the signal to noise ratio, the brightness temperature of the background, the difference between the temperature of the ambient air and the brightness temperature of the background, and the noise equivalent column density are produced. The column densities of all directions in which a target compound has been identified may be retrieved by a nonlinear least squares fitting algorithm and an additional false color image is displayed. The system has a high selectivity, low noise equivalent spectral radiance, and it allows identification, visualization, and quantification of pollutant clouds.

  1. Proceedings of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) Performance Evaluation Workshop

    NASA Technical Reports Server (NTRS)

    Vane, Gregg (Editor)

    1988-01-01

    The focus of the workshop was the assessment of data quality by the AVIRIS project. Summaries of 16 of the presentations are published. The AVIRIS performance evaluation period began in June 87 with flight data collection in the eastern U.S., and continued in the west until Oct. 87, after which the instrument was returned for post flight calibration. At the beginning, the sensor met all of the spatial, spectral and radiometric performance requirements except in spectrometer D, where the signal to noise ratio was below the required value. By the end, sensor performance had deteriorated due to failure of 2 critical parts and to some design deficiences. The independent assessment by the NASA investigators confirmed the assessment by the AVIRIS project. Some scientific results were derived and are presented. These include the mapping of the spatial variation of atmospheric precipitable water, detection of shift in chlorophyll red, and mineral identification.

  2. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS): Inflight radiometric calibration and the determination of surface reflectance

    NASA Technical Reports Server (NTRS)

    Conel, J. E.; Vane, G.; Green, R. O.; Alley, R. E.; Carere, V.; Gabell, A.; Bruegge, C. J.

    1988-01-01

    The inflight radiometric performance of AVIRIS is presented together with a comparison of methods of recovering surface spectral reflectance from the data. Performance is evaluated by comparing radiance predicted from AVIRIS with radiance generated from the LOWIRAN 6 atmospheric model and measured surface reflectance. Comparisons show apparent agreement to within a few percent between 1800 and 2450 nm. Between 600 and 1800 nm the response of AVIRIS is systematically low by as much as 70 percent, and between 400 and 600 nm it is higher than expected. These problems are traced to thermal distortions of the instrument, and to detachment during flight of optical fibers connecting foreoptics to two of four spectrometers in the instrument. Of three methods studied, an empirical one involving calibration curves constructed from field reflectance measurements returns accurate predictions of the surface reflectance independent of the actual radiometric significance of the flight data.

  3. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS): Sensor improvements for 1994 and 1995

    NASA Technical Reports Server (NTRS)

    Sarture, C. M.; Chrien, T. G.; Green, R. O.; Eastwood, M. L.; Raney, J. J.; Hernandez, M. A.

    1995-01-01

    AVIRIS is a NASA-sponsored Earth-remote-sensing imaging spectrometer designed, built and operated by the Jet Propulsion Laboratory (JPL). While AVIRIS has been operational since 1989, major improvements have been completed in most of the sensor subsystems during the winter maintenance cycles. As a consequence of these efforts, the capabilities of AVIRIS to reliably acquire and deliver consistently high quality, calibrated imaging spectrometer data continue to improve annually, significantly over those in 1989. Improvements to AVIRIS prior to 1994 have been described previously. This paper details recent and planned improvements to AVIRIS in the sensor task.

  4. Signal chain for the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Bunn, James S., Jr.

    1987-01-01

    The AVIRIS instrument has a separate dedicated analog signal processing chain for each of its four spectrometers. The signal chains amplify low-level focal-plane line array signals (5 to 10 mV full-scale span) in the presence of larger multiplexing signals (approx 150 mV) providing the data handling system a ten-bit digital word (for each spectrometer) each 1.3 microns. This signal chain provides automatic correction for the line array dark signal nonuniformity (which can approach the full-scale signal span).

  5. Spectral and radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Vane, Gregg; Chrien, Thomas G.; Miller, Edward A.; Reimer, John H.

    1987-01-01

    The laboratory spectral and radiometric calibration of the AVIRIS science data collected since 1987 is described. The instrumentation and procedures used in the calibration are discussed and the accuracy achieved in the laboratory as determined by measurement and calculation is compared with the requirements. Instrument performance factors affecting radiometry are described. The paper concludes with a discussion of future plans.

  6. Assessing stream temperature variations in the Pacific Northwest using airborne thermal infrared remote sensing

    NASA Astrophysics Data System (ADS)

    Tan, J.; Cherkauer, K. A.

    2010-12-01

    Stream temperature is an important indicator of water quality, and a significant concern for endangered cold-water fish species in the Pacific Northwest. Thermal-infrared (TIR) remote sensing allows for the observation of water temperatures in entire river systems in a relatively short space of time, as opposed to more traditional point-based in situ observing methods that can capture only localized water conditions. Point measurements can therefore miss important spatial patterns associated with various factors including exposure to solar radiation, urbanization, changes to riparian zone vegetation, and the presence of groundwater returns and springs. In this paper, we analyze moderate resolution TIR imagery collected from an airborne platform for the Green River in Washington State. Five-meter MODIS/ASTER (MASTER) imagery along the main channel of the Green River was acquired in multiple straight line passes with image overlaps occurring at time intervals of between 3 and 30 minutes on August 25 and 27, 2001. Overlaps of two adjacent images provide a detailed comparison of how stream temperature changes over relatively short time scales, while image captured from different days help identify persistent localized temperature differences. Trees and shrubs in the riparian zone increases shading of the stream and reduces along-stream increases in temperature compared to stream reaches with reduced shading, such as urban areas. Longitudinal profiles of stream temperature from upstream to downstream show that other factors, such as sandbars and cold-water seeps, also contribute to along-stream temperature variations.

  7. Airborne Thermal Infrared Multispectral Scanner (TIMS) images over disseminated gold deposits, Osgood Mountains, Humboldt County, Nevada

    NASA Technical Reports Server (NTRS)

    Krohn, M. Dennis

    1986-01-01

    The U.S. Geological Survey (USGS) acquired airborne Thermal Infrared Multispectral Scanner (TIMS) images over several disseminated gold deposits in northern Nevada in 1983. The aerial surveys were flown to determine whether TIMS data could depict jasperoids (siliceous replacement bodies) associated with the gold deposits. The TIMS data were collected over the Pinson and Getchell Mines in the Osgood Mountains, the Carlin, Maggie Creek, Bootstrap, and other mines in the Tuscarora Mountains, and the Jerritt Canyon Mine in the Independence Mountains. The TIMS data seem to be a useful supplement to conventional geochemical exploration for disseminated gold deposits in the western United States. Siliceous outcrops are readily separable in the TIMS image from other types of host rocks. Different forms of silicification are not readily separable, yet, due to limitations of spatial resolution and spectral dynamic range. Features associated with the disseminated gold deposits, such as the large intrusive bodies and fault structures, are also resolvable on TIMS data. Inclusion of high-resolution thermal inertia data would be a useful supplement to the TIMS data.

  8. Thermal physical property-based fusion of geostationary meteorological satellite visible and infrared channel images.

    PubMed

    Han, Lei; Shi, Lu; Yang, Yiling; Song, Dalei

    2014-06-10

    Geostationary meteorological satellite infrared (IR) channel data contain important spectral information for meteorological research and applications, but their spatial resolution is relatively low. The objective of this study is to obtain higher-resolution IR images. One common method of increasing resolution fuses the IR data with high-resolution visible (VIS) channel data. However, most existing image fusion methods focus only on visual performance, and often fail to take into account the thermal physical properties of the IR images. As a result, spectral distortion occurs frequently. To tackle this problem, we propose a thermal physical properties-based correction method for fusing geostationary meteorological satellite IR and VIS images. In our two-step process, the high-resolution structural features of the VIS image are first extracted and incorporated into the IR image using regular multi-resolution fusion approach, such as the multiwavelet analysis. This step significantly increases the visual details in the IR image, but fake thermal information may be included. Next, the Stefan-Boltzmann Law is applied to correct the distortion, to retain or recover the thermal infrared nature of the fused image. The results of both the qualitative and quantitative evaluation demonstrate that the proposed physical correction method both improves the spatial resolution and preserves the infrared thermal properties.

  9. A Fast Visible-Infrared Imaging Radiometer Suite Simulator for Cloudy Atmopheres

    NASA Technical Reports Server (NTRS)

    Liu, Chao; Yang, Ping; Nasiri, Shaima L.; Platnick, Steven; Meyer, Kerry G.; Wang, Chen Xi; Ding, Shouguo

    2015-01-01

    A fast instrument simulator is developed to simulate the observations made in cloudy atmospheres by the Visible Infrared Imaging Radiometer Suite (VIIRS). The correlated k-distribution (CKD) technique is used to compute the transmissivity of absorbing atmospheric gases. The bulk scattering properties of ice clouds used in this study are based on the ice model used for the MODIS Collection 6 ice cloud products. Two fast radiative transfer models based on pre-computed ice cloud look-up-tables are used for the VIIRS solar and infrared channels. The accuracy and efficiency of the fast simulator are quantify in comparison with a combination of the rigorous line-by-line (LBLRTM) and discrete ordinate radiative transfer (DISORT) models. Relative errors are less than 2 for simulated TOA reflectances for the solar channels and the brightness temperature differences for the infrared channels are less than 0.2 K. The simulator is over three orders of magnitude faster than the benchmark LBLRTM+DISORT model. Furthermore, the cloudy atmosphere reflectances and brightness temperatures from the fast VIIRS simulator compare favorably with those from VIIRS observations.

  10. Modified Visible and Infrared Optical Design for the ITER Upper Ports

    SciTech Connect

    Lasnier, C; Seppala, L; Morris, K

    2008-04-24

    This document reports the results of a follow-on optical design study of visible-light and infrared optics for the ITER upper ports, performed by LLNL under contract for the US ITER Project Office. The major objectives of this work are to move the viewing aperture closer to the plasma so that the optical path does not cut through any adjacent blanket shield module other than the module designated for the port; move optics forward into the port tube to increase the aperture size and therefore improve the spatial resolution; assess the trade-off between spatial resolution and spatial coverage by reducing the field of view; and create a mechanical model with a neutron labyrinth. Here we show an optical design incorporating all these aspects. The new design fits into a 360 mm ID tube, as did the previous design. The entrance aperture is increased from 10 mm to 21 mm, with a corresponding increase in spatial resolution. The Airy disk diameter for 3.8 {micro}m wavelength IR light is 5.1 mm at the most distant target point in the field of view. The field of view is reduced from 60 toroidal degrees (full toroidal coverage with 6 cameras) to 50 toroidal degrees. The 10 degrees eliminated are those nearest the camera, which have the poorest view of the divertor plate and in fact saw little of the plate. The Cassegrain telescope that was outside the vacuum windows in the previous design is now in vacuum, along with lenses for visible light. The Cassegrain for visible light is eliminated. An additional set of optical relay lenses is added for the visible and for the IR.

  11. Summaries of the Seventh JPL Airborne Earth Science Workshop January 12-16, 1998. Volume 1; AVIRIS Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O. (Editor)

    1998-01-01

    This publication contains the summaries for the Seventh JPL Airborne Earth Science Workshop, held in Pasadena, California, on January 12-16, 1998. The main workshop is divided into three smaller workshops, and each workshop has a volume as follows: (1) Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) Workshop; (2) Airborne Synthetic Aperture Radar (AIRSAR) Workshop; and (3) Thermal Infrared Multispectral Scanner (TIMS) Workshop. This Volume 1 publication contains 58 papers taken from the AVIRIS workshop.

  12. Discrimination of tomatoes bred by spaceflight mutagenesis using visible/near infrared spectroscopy and chemometrics.

    PubMed

    Shao, Yongni; Xie, Chuanqi; Jiang, Linjun; Shi, Jiahui; Zhu, Jiajin; He, Yong

    2015-04-01

    Visible/near infrared spectroscopy (Vis/NIR) based on sensitive wavelengths (SWs) and chemometrics was proposed to discriminate different tomatoes bred by spaceflight mutagenesis from their leafs or fruits (green or mature). The tomato breeds were mutant M1, M2 and their parent. Partial least squares (PLS) analysis and least squares-support vector machine (LS-SVM) were implemented for calibration models. PLS analysis was implemented for calibration models with different wavebands including the visible region (400-700 nm) and the near infrared region (700-1000 nm). The best PLS models were achieved in the visible region for the leaf and green fruit samples and in the near infrared region for the mature fruit samples. Furthermore, different latent variables (4-8 LVs for leafs, 5-9 LVs for green fruits, and 4-9 LVs for mature fruits) were used as inputs of LS-SVM to develop the LV-LS-SVM models with the grid search technique and radial basis function (RBF) kernel. The optimal LV-LS-SVM models were achieved with six LVs for the leaf samples, seven LVs for green fruits, and six LVs for mature fruits, respectively, and they outperformed the PLS models. Moreover, independent component analysis (ICA) was executed to select several SWs based on loading weights. The optimal LS-SVM model was achieved with SWs of 550-560 nm, 562-574 nm, 670-680 nm and 705-71 5 nm for the leaf samples; 548-556 nm, 559-564 nm, 678-685 nm and 962-974 nm for the green fruit samples; and 712-718 nm, 720-729 nm, 968-978 nm and 820-830 nm for the mature fruit samples. All of them had better performance than PLS and LV-LS-SVM, with the parameters of correlation coefficient (rp), root mean square error of prediction (RMSEP) and bias of 0.9792, 0.2632 and 0.0901 based on leaf discrimination, 0.9837, 0.2783 and 0.1758 based on green fruit discrimination, 0.9804, 0.2215 and -0.0035 based on mature fruit discrimination, respectively. The overall results indicated that ICA was an effective way for the

  13. Discrimination of tomatoes bred by spaceflight mutagenesis using visible/near infrared spectroscopy and chemometrics

    NASA Astrophysics Data System (ADS)

    Shao, Yongni; Xie, Chuanqi; Jiang, Linjun; Shi, Jiahui; Zhu, Jiajin; He, Yong

    2015-04-01

    Visible/near infrared spectroscopy (Vis/NIR) based on sensitive wavelengths (SWs) and chemometrics was proposed to discriminate different tomatoes bred by spaceflight mutagenesis from their leafs or fruits (green or mature). The tomato breeds were mutant M1, M2 and their parent. Partial least squares (PLS) analysis and least squares-support vector machine (LS-SVM) were implemented for calibration models. PLS analysis was implemented for calibration models with different wavebands including the visible region (400-700 nm) and the near infrared region (700-1000 nm). The best PLS models were achieved in the visible region for the leaf and green fruit samples and in the near infrared region for the mature fruit samples. Furthermore, different latent variables (4-8 LVs for leafs, 5-9 LVs for green fruits, and 4-9 LVs for mature fruits) were used as inputs of LS-SVM to develop the LV-LS-SVM models with the grid search technique and radial basis function (RBF) kernel. The optimal LV-LS-SVM models were achieved with six LVs for the leaf samples, seven LVs for green fruits, and six LVs for mature fruits, respectively, and they outperformed the PLS models. Moreover, independent component analysis (ICA) was executed to select several SWs based on loading weights. The optimal LS-SVM model was achieved with SWs of 550-560 nm, 562-574 nm, 670-680 nm and 705-715 nm for the leaf samples; 548-556 nm, 559-564 nm, 678-685 nm and 962-974 nm for the green fruit samples; and 712-718 nm, 720-729 nm, 968-978 nm and 820-830 nm for the mature fruit samples. All of them had better performance than PLS and LV-LS-SVM, with the parameters of correlation coefficient (rp), root mean square error of prediction (RMSEP) and bias of 0.9792, 0.2632 and 0.0901 based on leaf discrimination, 0.9837, 0.2783 and 0.1758 based on green fruit discrimination, 0.9804, 0.2215 and -0.0035 based on mature fruit discrimination, respectively. The overall results indicated that ICA was an effective way for the

  14. High Spatial Resolution Airborne Multispectral Thermal Infrared Remote Sensing Data for Analysis of Urban Landscape Characteristics

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G., Jr.; Arnold, James E. (Technical Monitor)

    2000-01-01

    We have used airborne multispectral thermal infrared (TIR) remote sensing data collected at a high spatial resolution (i.e., 10m) over several cities in the United States to study thermal energy characteristics of the urban landscape. These TIR data provide a unique opportunity to quantify thermal responses from discrete surfaces typical of the urban landscape and to identify both the spatial arrangement and patterns of thermal processes across the city. The information obtained from these data is critical to understanding how urban surfaces drive or force development of the Urban Heat Island (UHI) effect, which exists as a dome of elevated air temperatures that presides over cities in contrast to surrounding non-urbanized areas. The UHI is most pronounced in the summertime where urban surfaces, such as rooftops and pavement, store solar radiation throughout the day, and release this stored energy slowly after sunset creating air temperatures over the city that are in excess of 2-4'C warmer in contrast with non-urban or rural air temperatures. The UHI can also exist as a daytime phenomenon with surface temperatures in downtown areas of cities exceeding 38'C. The implications of the UHI are significant, particularly as an additive source of thermal energy input that exacerbates the overall production of ground level ozone over cities. We have used the Airborne Thermal and Land Applications Sensor (ATLAS), flown onboard a Lear 23 jet aircraft from the NASA Stennis Space Center, to acquire high spatial resolution multispectral TIR data (i.e., 6 bandwidths between 8.2-12.2 (um) over Huntsville, Alabama, Atlanta, Georgia, Baton Rouge, Louisiana, Salt Lake City, Utah, and Sacramento, California. These TIR data have been used to produce maps and other products, showing the spatial distribution of heating and cooling patterns over these cities to better understand how the morphology of the urban landscape affects development of the UHI. In turn, these data have been used

  15. [Generation of reactive oxygen species in water under exposure of visible or infrared irradiation at absorption band of molecular oxygen].

    PubMed

    Gudkov, S V; Karp, O E; Garmash, S A; Ivanov, V E; Chernikov, A V; Manokhin, A A; Astashev, M E; Iaguzhinskiĭ, L S; Bruskov, V I

    2012-01-01

    It is found that in bidistilled water saturated with oxygen hydrogen peroxide and hydroxyl radicals are formed under the influence of visible and infrared radiation in the absorption bands of molecular oxygen. Formation of reactive oxygen species (ROS) occurs under the influence of both solar and artificial light sourses, including the coherent laser irradiation. The oxygen effect, i.e. the impact of dissolved oxygen concentration on production of hydrogen peroxide induced by light, is detected. It is shown that the visible and infrared radiation in the absorption bands of molecular oxygen leads to the formation of 8-oxoguanine in DNA in vitro. Physicochemical mechanisms of ROS formation in water when exposed to visible and infrared light are studied, and the involvement of singlet oxygen and superoxide anion radicals in this process is shown.

  16. Comprehensive Pyrometry of Incandescent Multiwalled Carbon Nanotubes and Graphene in the Visible and Near Infrared

    NASA Astrophysics Data System (ADS)

    Singer, Scott Benjamin

    Pyrometry via blackbody radiation is used to measure temperature of systems throughout physics. The spectrum, described by Planck's law, depends solely on the temperature T and surface area A of a black source. However, the derivation of Planck's law considers only the limit where wavelength lambda << L, the linear dimension of the source. Many nanosystems, however, exist in the opposite limit, lambda ≳ L, in the visible and near infrared. We investigate this subwavelength limit of thermal radiation by bringing multi-walled carbon nanotubes, for which r << lambda ≲ L, to incandescence via joule heating. Their light is measured in an optical microscope, and their geometry is measured with a transmission electron microscope. With complete knowledge of the source geometry and the photon emission, a full characterization of the temperature, thermal conductivity, and electrical conductivity of each nanofilament is possible. We find that the filaments emit highly polarized light with suprablack effective emissivities, indicative of thermal radiation originating in a phase coherent manner from the nanotube's volume as opposed to its surface area, in concordance with classical electromagnetism. Multiwavelength pyrometry is then performed on graphene, which has linear dimensions in the classical blackbody limit and theoretical gray emission. This pyrometry allows us to measure the number of layers in the graphene, a result confirmed with absorption measurements in agreement with Kirchoff's law of thermal radiation. Light emitted from incandescent graphene's bulk is found to be unpolarized, yet exhibits polarization as high as 20% near the sheet edge in accordance with diffraction theory. However, light polarized to 5% is observed originating from the bulk away from the hot region, which we attribute to anisotropy in the temperature gradient. We also find that as temperature of a nanotube and graphene increases, the signal in the near infrared becomes suppressed compared

  17. Visualization of light propagation in visible Chinese human head for functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Ting; Gong, Hui; Luo, Qingming

    2011-04-01

    Using the visible Chinese human data set, which faithfully represents human anatomy, we visualize the light propagation in the head in detail based on Monte Carlo simulation. The simulation is verified to agree with published experimental results in terms of a differential path-length factor. The spatial sensitivity profile turns out to seem like a fat tropical fish with strong distortion along the folding cerebral surface. The sensitive brain region covers the gray matter and extends to the superficial white matter, leading to a large penetration depth (>3 cm). Finally, the optimal source-detector separation is suggested to be narrowed down to 3-3.5 cm, while the sensitivity of the detected signal to brain activation reaches the peak of 8%. These results indicate that the cerebral cortex folding geometry actually has substantial effects on light propagation, which should be necessarily considered for applications of functional near-infrared spectroscopy.

  18. Broad spectral domain fluorescence wavelength modulation of visible and near-infrared emissive polymersomes.

    PubMed

    Ghoroghchian, P Peter; Frail, Paul R; Susumu, Kimihiro; Park, Tae-Hong; Wu, Sophia P; Uyeda, H Tetsuo; Hammer, Daniel A; Therien, Michael J

    2005-11-01

    Incorporation of an extended family of multi[(porphinato)zinc(II)] (PZn)-based supermolecular fluorophores into the lamellar membranes of polymersomes (50 nm to 50 mum diameter polymer vesicles) gives rise to electrooptically diverse nano-to-micron (meso) scale soft materials. Studies that examine homogeneous suspensions of 100 nm diameter emissive polymersomes demonstrate fluorescence energy modulation over a broad spectral domain of the visible and near-infrared (600-900 nm). These polymersomal structures highlight that the nature of intermembranous polymer-to-fluorophore contacts depends on the position and identity of the porphyrins' phenyl ring substituents. Emissive polymersomes are shown to possess reduced spectral heterogeneity with respect to the established optical signatures of these PZn-based supermolecular fluorophores in solution; additionally, selection of fluorophore ancillary substituents predictably controls the nature of polymer-emitter noncovalent interactions to provide an important additional mechanism to further modulate the fluorescence band maxima of these meso-scale emissive vesicles.

  19. Visible and infrared investigations of planet-crossing asteroids and outer solar system objects

    NASA Technical Reports Server (NTRS)

    Tholen, David J.

    1991-01-01

    A major effort was directed toward 951 Gaspra in preparation for the Galileo encounter in October 1991. Most of the observational work involved photometry, for purposes of investigating the rotational state and phase function of the asteroid to help plan the encounter, and for purposes of navigating the spacecraft to the object. Work was also done with radiometric data obtained with the IRTF at NASA's request, for which simultaneous visible photometry was acquired with the University of Hawaii 2.24-m telescope. The results from the observations made during the 1990 opposition were published by Goldader et al. The main results reported include a rotational period of 7.04246 hours, an absolute visual magnitude of 11.8026, a slope parameter of 0.285, an early estimate of a high obliquity, an infrared spectrum indicating an olivine-rich composition, and 13 astrometric positions.

  20. Study of varnish layers with optical coherence tomography in both visible and infrared domains

    NASA Astrophysics Data System (ADS)

    Latour, Gaël; Georges, Gaëlle; Siozade, Laure; Deumié, Carole; Echard, Jean-Philippe

    2009-07-01

    Optical Coherence Tomography (OCT) is an attractive technique to study works of art because it allows non-destructive and contactless analysis. In the case of musical instruments, the study of wood finishes could give interesting information as the thicknesses of the layers, the number of layers and the presence of fillers. A time-domain full-field OCT, achieving high resolution, is used in both visible and near infrared ranges to characterize semi-transparent layers containing scattering particles as charged varnish layers. We present OCT measurements on wood varnished with different coatings. We show that the detection of pigment particles is dependent of the spectral range and that both spectral domains allow to reach micrometer-scale spatial resolutions.

  1. Sediment mineralogy based on visible and near-infrared reflectance spectroscopy

    USGS Publications Warehouse

    Jarrard, R.D.; Vanden Berg, M.D.; ,

    2006-01-01

    Visible and near-infrared spectroscopy (VNIS) can be used to measure reflectance spectra (wavelength 350-2500 nm) for sediment cores and samples. A local ground-truth calibration of spectral features to mineral percentages is calculated by measuring reflectance spectra for a suite of samples of known mineralogy. This approach has been tested on powders, core plugs and split cores, and we conclude that it works well on all three, unless pore water is present. Initial VNIS studies have concentrated on determination of relative proportions of carbonate, opal, smectite and illite in equatorial Pacific sediments. Shipboard VNIS-based determination of these four components was demonstrated on Ocean Drilling Program Leg 199. ?? The Geological Society of London 2006.

  2. Effects of polychromatic visible and infrared light on biological liquid media.

    PubMed

    Zilov, V G; Khadartsev, A A; Bitsoev, V D

    2014-08-01

    Experimental study of the effects of polychromatic visible and infrared light on biological fluids was carried out in order to validate the new approaches to phototherapy. Polychromatic light generated by Bioptron device at different modes and frequencies was released through the fiberoptic cable, including the exposure paralleled by CO2 saturation of water and exposure from a device placed 10 cm above the water surface, which ensured maximum light absorption. The effects of irradiation were recorded in 26 and 15 min, while the increase of light absorption by blood plasma in vivo was recorded 1 h after a bath with water pre-exposed to polarized light. Absorption bands corresponding to those for immunomodulatory, anti-inflammatory, and antiviral drugs, were detected. Changes in the spectra of valency oscillations, depending on the oscillation anharmonism values, were detected.

  3. Opto-mechanical system design of test system for near-infrared and visible target

    NASA Astrophysics Data System (ADS)

    Wang, Chunyan; Zhu, Guodong; Wang, Yuchao

    2014-12-01

    Guidance precision is the key indexes of the guided weapon shooting. The factors of guidance precision including: information processing precision, control system accuracy, laser irradiation accuracy and so on. The laser irradiation precision is an important factor. This paper aimed at the demand of the precision test of laser irradiator,and developed the laser precision test system. The system consists of modified cassegrain system, the wide range CCD camera, tracking turntable and industrial PC, and makes visible light and near infrared target imaging at the same time with a Near IR camera. Through the analysis of the design results, when it exposures the target of 1000 meters that the system measurement precision is43mm, fully meet the needs of the laser precision test.

  4. Discriminant analyzing system for wood wastes using a visible-near-infrared chemometric imaging technique.

    PubMed

    Kobori, Hikaru; Yonenobu, Hitoshi; Noma, Junichi; Tsuchikawa, Satoru

    2008-08-01

    A new optical system was developed and applied to automated separation of wood wastes, using a combined technique of visible-near-infrared (Vis-NIR) imaging analysis and chemometrics. Three kinds of typical wood wastes were used, i.e., non-treated, impregnated, and plastic-film overlaid wood. The classification model based on soft independent modeling of class analogy (SIMCA) was examined using the difference luminance brightness of a sample. Our newly developed system showed a good/promising performance in separation of wood wastes, with an average rate of correct separation of 89%. Hence, it is concluded that the system is efficiently feasible for online monitoring and separation of wood wastes in recycling mills.

  5. Visible-infrared achromatic imaging by wavefront coding with wide-angle automobile camera

    NASA Astrophysics Data System (ADS)

    Ohta, Mitsuhiko; Sakita, Koichi; Shimano, Takeshi; Sugiyama, Takashi; Shibasaki, Susumu

    2016-09-01

    We perform an experiment of achromatic imaging with wavefront coding (WFC) using a wide-angle automobile lens. Our original annular phase mask for WFC was inserted to the lens, for which the difference between the focal positions at 400 nm and at 950 nm is 0.10 mm. We acquired images of objects using a WFC camera with this lens under the conditions of visible and infrared light. As a result, the effect of the removal of the chromatic aberration of the WFC system was successfully determined. Moreover, we fabricated a demonstration set assuming the use of a night vision camera in an automobile and showed the effect of the WFC system.

  6. Somewhere under the rainbow: the visible to far infrared imaging lens

    NASA Astrophysics Data System (ADS)

    Palmer, Troy A.; Alexay, Christopher C.; Vogel, Steven

    2011-06-01

    This article explores the complex design challenges of optical imaging systems that can operate over a broad range of the electromagnetic spectrum, covering all bands from the visible to the far infrared simultaneously. Although the focus is placed on a refractive solution to these challenges, an effort to outline the limitations of reflective solutions is also presented. After exploring a novel method to optimize the choice of optical materials, an elegant and efficient example is provided: a refractive lens that is at once a total optical solution (one lens covering a broad spectral range) and a common aperture solution (one lens that works simultaneously with several camera types). This solution, StingRay Optics' own SuperBandTM Optic, is ultimately explored in its functionality to address this need in an advantageous manner.

  7. Time-cumulated visible and infrared radiance histograms used as descriptors of surface and cloud variations

    NASA Technical Reports Server (NTRS)

    Seze, Genevieve; Rossow, William B.

    1991-01-01

    The spatial and temporal stability of the distributions of satellite-measured visible and infrared radiances, caused by variations in clouds and surfaces, are investigated using bidimensional and monodimensional histograms and time-composite images. Similar analysis of the histograms of the original and time-composite images provides separation of the contributions of the space and time variations to the total variations. The variability of both the surfaces and clouds is found to be larger at scales much larger than the minimum resolved by satellite imagery. This study shows that the shapes of these histograms are distinctive characteristics of the different climate regimes and that particular attributes of these histograms can be related to several general, though not universal, properties of clouds and surface variations at regional and synoptic scales. There are also significant exceptions to these relationships in particular climate regimes. The characteristics of these radiance histograms provide a stable well defined descriptor of the cloud and surface properties.

  8. NPOESS Preparatory Project Validation Program for the Visible/Infrared Imager/Radiometer Suite

    NASA Astrophysics Data System (ADS)

    Kopp, T.; Arnone, R. A.; Hutchison, K.; Jackson, J. M.; Kilcoyne, H.; Plonski, M.; Reed, B.; Sei, A.; Starr, D.; Wong, E.; Privette, J. L.

    2009-12-01

    The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Program, in partnership with National Aeronautical Space Administration (NASA), will launch the NPOESS Preparatory Project (NPP), a risk reduction and data continuity mission, prior to the first operational NPOESS launch. The NPOESS Program, in partnership with Northrop Grumman Aerospace Systems, will execute the NPP Calibration and Validation (Cal/Val) program to ensure the data products comply with the requirements of the sponsoring agencies. The Visible/Infrared Imager/Radiometer Suite will produce 22 EDRs, including Imagery, cloud, aerosol, ocean, and land products. The calibration and validation plans establish science and user community leadership and participation, and demonstrated, cost-effective Cal/Val approaches. This presentation will provide an overview of the NPP Cal/Val plans for the VIIRS environmental data products.

  9. Potential of remote visible and near-infrared spectral reflectance measurements for mapping thermal maturity variations

    SciTech Connect

    Rowan, L.C.; Pawlewicz, M.J.; Jones, O.D. )

    1989-09-01

    The visible and near-infrared (VNIR) spectral reflectance of rocks containing organic matter is related to thermal maturity because thermal alteration liberates hydrogen and forms highly absorbing carbon-rich polycondensed structures. To evaluate the usefulness of remote spectral reflectance measurements for mapping thermal maturity differences, Landsat Thematic Mapper (TM) images of the Eureka, Nevada, area were processed to produce a digital classification image maps that shows maturity in well-exposed, sparsely vegetated areas consisting of Chainman Shale. The relationship between spectral reflectance in TM bands and band ratios and maturity was confirmed through analysis of laboratory VNIR spectral reflectance and mean vitrinite reflectance (R{sub m}) measurements of 20 samples.

  10. Hybrid Molecule-Nanocrystal Photon Upconversion Across the Visible and Near-Infrared.

    PubMed

    Huang, Zhiyuan; Li, Xin; Mahboub, Melika; Hanson, Kerry M; Nichols, Valerie M; Le, Hoang; Tang, Ming L; Bardeen, Christopher J

    2015-08-12

    The ability to upconvert two low energy photons into one high energy photon has potential applications in solar energy, biological imaging, and data storage. In this Letter, CdSe and PbSe semiconductor nanocrystals are combined with molecular emitters (diphenylanthracene and rubrene) to upconvert photons in both the visible and the near-infrared spectral regions. Absorption of low energy photons by the nanocrystals is followed by energy transfer to the molecular triplet states, which then undergo triplet-triplet annihilation to create high energy singlet states that emit upconverted light. By using conjugated organic ligands on the CdSe nanocrystals to form an energy cascade, the upconversion process could be enhanced by up to 3 orders of magnitude. The use of different combinations of nanocrystals and emitters shows that this platform has great flexibility in the choice of both excitation and emission wavelengths.

  11. Fast Measurement of Soluble Solid Content in Mango Based on Visible and Infrared Spectroscopy Technique

    NASA Astrophysics Data System (ADS)

    Yu, Jiajia; He, Yong

    Mango is a kind of popular tropical fruit, and the soluble solid content is an important in this study visible and short-wave near-infrared spectroscopy (VIS/SWNIR) technique was applied. For sake of investigating the feasibility of using VIS/SWNIR spectroscopy to measure the soluble solid content in mango, and validating the performance of selected sensitive bands, for the calibration set was formed by 135 mango samples, while the remaining 45 mango samples for the prediction set. The combination of partial least squares and backpropagation artificial neural networks (PLS-BP) was used to calculate the prediction model based on raw spectrum data. Based on PLS-BP, the determination coefficient for prediction (Rp) was 0.757 and root mean square and the process is simple and easy to operate. Compared with the Partial least squares (PLS) result, the performance of PLS-BP is better.

  12. Hybrid Molecule-Nanocrystal Photon Upconversion Across the Visible and Near-Infrared.

    PubMed

    Huang, Zhiyuan; Li, Xin; Mahboub, Melika; Hanson, Kerry M; Nichols, Valerie M; Le, Hoang; Tang, Ming L; Bardeen, Christopher J

    2015-08-12

    The ability to upconvert two low energy photons into one high energy photon has potential applications in solar energy, biological imaging, and data storage. In this Letter, CdSe and PbSe semiconductor nanocrystals are combined with molecular emitters (diphenylanthracene and rubrene) to upconvert photons in both the visible and the near-infrared spectral regions. Absorption of low energy photons by the nanocrystals is followed by energy transfer to the molecular triplet states, which then undergo triplet-triplet annihilation to create high energy singlet states that emit upconverted light. By using conjugated organic ligands on the CdSe nanocrystals to form an energy cascade, the upconversion process could be enhanced by up to 3 orders of magnitude. The use of different combinations of nanocrystals and emitters shows that this platform has great flexibility in the choice of both excitation and emission wavelengths. PMID:26161875

  13. The phase transition in VO2 probed using x-ray, visible and infrared radiations

    NASA Astrophysics Data System (ADS)

    Kumar, Suhas; Strachan, John Paul; Kilcoyne, A. L. David; Tyliszczak, Tolek; Pickett, Matthew D.; Santori, Charles; Gibson, Gary; Williams, R. Stanley

    2016-02-01

    Vanadium dioxide (VO2) is a model system that has been used to understand closely occurring multiband electronic (Mott) and structural (Peierls) transitions for over half a century due to continued scientific and technological interests. Among the many techniques used to study VO2, the most frequently used involve electromagnetic radiation as a probe. Understanding of the distinct physical information provided by different probing radiations is incomplete, mostly owing to the complicated nature of the phase transitions. Here, we use transmission of spatially averaged infrared (λ = 1.5 μm) and visible (λ = 500 nm) radiations followed by spectroscopy and nanoscale imaging using x-rays (λ = 2.25-2.38 nm) to probe the same VO2 sample while controlling the ambient temperature across its hysteretic phase transitions and monitoring its electrical resistance. We directly observed nanoscale puddles of distinct electronic and structural compositions during the transition. The two main results are that, during both heating and cooling, the transition of infrared and visible transmission occurs at significantly lower temperatures than the Mott transition, and the electronic (Mott) transition occurs before the structural (Peierls) transition in temperature. We use our data to provide insights into possible microphysical origins of the different transition characteristics. We highlight that it is important to understand these effects because small changes in the nature of the probe can yield quantitatively, and even qualitatively, different results when applied to a non-trivial multiband phase transition. Our results guide more judicious use of probe type and interpretation of the resulting data.

  14. An adaptive fusion approach for infrared and visible images based on NSCT and compressed sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Qiong; Maldague, Xavier

    2016-01-01

    A novel nonsubsampled contourlet transform (NSCT) based image fusion approach, implementing an adaptive-Gaussian (AG) fuzzy membership method, compressed sensing (CS) technique, total variation (TV) based gradient descent reconstruction algorithm, is proposed for the fusion computation of infrared and visible images. Compared with wavelet, contourlet, or any other multi-resolution analysis method, NSCT has many evident advantages, such as multi-scale, multi-direction, and translation invariance. As is known, a fuzzy set is characterized by its membership function (MF), while the commonly known Gaussian fuzzy membership degree can be introduced to establish an adaptive control of the fusion processing. The compressed sensing technique can sparsely sample the image information in a certain sampling rate, and the sparse signal can be recovered by solving a convex problem employing gradient descent based iterative algorithm(s). In the proposed fusion process, the pre-enhanced infrared image and the visible image are decomposed into low-frequency subbands and high-frequency subbands, respectively, via the NSCT method as a first step. The low-frequency coefficients are fused using the adaptive regional average energy rule; the highest-frequency coefficients are fused using the maximum absolute selection rule; the other high-frequency coefficients are sparsely sampled, fused using the adaptive-Gaussian regional standard deviation rule, and then recovered by employing the total variation based gradient descent recovery algorithm. Experimental results and human visual perception illustrate the effectiveness and advantages of the proposed fusion approach. The efficiency and robustness are also analyzed and discussed through different evaluation methods, such as the standard deviation, Shannon entropy, root-mean-square error, mutual information and edge-based similarity index.

  15. Comparison of two methodologies for calibrating satellite instruments in the visible and near-infrared.

    PubMed

    Barnes, Robert A; Brown, Steven W; Lykke, Keith R; Guenther, Bruce; Butler, James J; Schwarting, Thomas; Turpie, Kevin; Moyer, David; DeLuccia, Frank; Moeller, Christopher

    2015-12-10

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field of view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere's absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as lamp-illuminated integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project Visible Infrared Imaging Radiometer Suite sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered. PMID:26836861

  16. Fusion of infrared and visible images based on BEMD and NSDFB

    NASA Astrophysics Data System (ADS)

    Zhu, Pan; Huang, Zhanhua; Lei, Hai

    2016-07-01

    This paper presents a new fusion method based on the adaptive multi-scale decomposition of bidimensional empirical mode decomposition (BEMD) and the flexible directional expansion of nonsubsampled directional filter banks (NSDFB) for visible-infrared images. Compared with conventional multi-scale fusion methods, BEMD is non-parametric and completely data-driven, which is relatively more suitable for non-linear signals decomposition and fusion. NSDFB can provide direction filtering on the decomposition levels to capture more geometrical structure of the source images effectively. In our fusion framework, the entropies of the two patterns of source images are firstly calculated and the residue of the image whose entropy is larger is extracted to make it highly relevant with the other source image. Then, the residue and the other source image are decomposed into low-frequency sub-bands and a sequence of high-frequency directional sub-bands in different scales by using BEMD and NSDFB. In this fusion scheme, two relevant fusion rules are used in low-frequency sub-bands and high-frequency directional sub-bands, respectively. Finally, the fused image is obtained by applying corresponding inverse transform. Experimental results indicate that the proposed fusion algorithm can obtain state-of-the-art performance for visible-infrared images fusion in both aspects of objective assessment and subjective visual quality even for the source images obtained in different conditions. Furthermore, the fused results have high contrast, remarkable target information and rich details information that are more suitable for human visual characteristics or machine perception.

  17. Visible light and near-infrared-responsive chromophores for drug delivery-on-demand applications.

    PubMed

    Linsley, Chase S; Quach, Viola Y; Agrawal, Gaurav; Hartnett, Elyse; Wu, Benjamin M

    2015-12-01

    The need for temporal-spatial control over the release of biologically active molecules has motivated efforts to engineer novel drug delivery-on-demand strategies actuated via light irradiation. Many systems, however, have been limited to in vitro proof-of-concept due to biocompatibility issues with the photo-responsive moieties or the light wavelength, intensity, and duration. To overcome these limitations, this paper describes a light actuated drug delivery-on-demand strategy that uses visible and near-infrared (NIR) light and biocompatible chromophores: cardiogreen, methylene blue, and riboflavin. All three chromophores are capable of significant photothermal reaction upon exposure to NIR and visible light, and the amount of temperature change is dependent upon light intensity, wavelength as well as chromophore concentration. Pulsatile release of bovine serum albumin (BSA) from thermally responsive hydrogels was achieved over 4 days. These findings have the potential to translate light-actuated drug delivery-on-demand systems from the bench to clinical applications that require explicit control over the presentation of biologically active molecules.

  18. Visible light and near infrared-responsive chromophores for drug delivery-on-demand applications

    PubMed Central

    Linsley, Chase S.; Quach, Viola Y.; Agrawal, Gaurav; Hartnett, Elyse; Wu, Benjamin M.

    2016-01-01

    The need for temporal-spatial control over the release of biologically active molecules has motivated efforts to engineer novel drug delivery-on-demand strategies actuated via light irradiation. Many systems, however, have been limited to in vitro proof-of-concept due to biocompatibility issues with the photo-responsive moieties or the light wavelength, intensity and duration. To overcome these limitations, this paper describes a light actuated drug delivery-on-demand strategy that uses visible and near infrared (NIR) light and biocompatible chromophores: cardiogreen, methylene blue and riboflavin. All 3 chromophores are capable of significant photothermal reaction upon exposure to NIR and visible light, and the amount of temperature change is dependent upon light intensity, wavelength as well as chromophore concentration. Pulsatile release of bovine serum albumin (BSA) from thermally-responsive hydrogels was achieved over 4 days. These findings have the potential to translate light actuated drug delivery-on-demand systems from the bench to clinical applications that require explicit control over the presentation of biologically active molecules. PMID:26423655

  19. Simultaneous real-time visible and infrared video with single-pixel detectors

    NASA Astrophysics Data System (ADS)

    Edgar, Matthew. P.; Gibson, Graham M.; Bowman, Richard W.; Sun, Baoqing; Radwell, Neal; Mitchell, Kevin J.; Welsh, Stephen S.; Padgett, Miles J.

    2015-05-01

    Conventional cameras rely upon a pixelated sensor to provide spatial resolution. An alternative approach replaces the sensor with a pixelated transmission mask encoded with a series of binary patterns. Combining knowledge of the series of patterns and the associated filtered intensities, measured by single-pixel detectors, allows an image to be deduced through data inversion. In this work we extend the concept of a ‘single-pixel camera’ to provide continuous real-time video at 10 Hz , simultaneously in the visible and short-wave infrared, using an efficient computer algorithm. We demonstrate our camera for imaging through smoke, through a tinted screen, whilst performing compressive sampling and recovering high-resolution detail by arbitrarily controlling the pixel-binning of the masks. We anticipate real-time single-pixel video cameras to have considerable importance where pixelated sensors are limited, allowing for low-cost, non-visible imaging systems in applications such as night-vision, gas sensing and medical diagnostics.

  20. Simultaneous real-time visible and infrared video with single-pixel detectors.

    PubMed

    Edgar, Matthew P; Gibson, Graham M; Bowman, Richard W; Sun, Baoqing; Radwell, Neal; Mitchell, Kevin J; Welsh, Stephen S; Padgett, Miles J

    2015-01-01

    Conventional cameras rely upon a pixelated sensor to provide spatial resolution. An alternative approach replaces the sensor with a pixelated transmission mask encoded with a series of binary patterns. Combining knowledge of the series of patterns and the associated filtered intensities, measured by single-pixel detectors, allows an image to be deduced through data inversion. In this work we extend the concept of a 'single-pixel camera' to provide continuous real-time video at 10 Hz , simultaneously in the visible and short-wave infrared, using an efficient computer algorithm. We demonstrate our camera for imaging through smoke, through a tinted screen, whilst performing compressive sampling and recovering high-resolution detail by arbitrarily controlling the pixel-binning of the masks. We anticipate real-time single-pixel video cameras to have considerable importance where pixelated sensors are limited, allowing for low-cost, non-visible imaging systems in applications such as night-vision, gas sensing and medical diagnostics. PMID:26001092

  1. A versatile femtosecond stimulated Raman spectroscopy setup with tunable pulses in the visible to near infrared

    SciTech Connect

    Zhu, Liangdong; Liu, Weimin; Fang, Chong

    2014-07-28

    We demonstrate a versatile and efficient setup to perform femtosecond stimulated Raman spectroscopy (FSRS). Technical innovations are implemented to achieve the wavelength tunability for both the picosecond narrowband Raman pump pulse and femtosecond broadband Raman probe pulse. Using a simplified one-grating scheme in a home-built second harmonic bandwidth compressor followed by a two-stage noncollinear optical parametric amplifier, we tune the Raman pump pulse from ca. 480 to 750 nm. To generate the suitable Raman probe pulse in tandem, we rely on our recently demonstrated broadband up-converted multicolor array technique that readily provides tunable broadband laser sidebands across the visible to near-infrared range. This unique setup has unparalleled flexibility for conducting FSRS. We measure the ground-state Raman spectra of a cyclohexane standard using tunable pump-probe pairs at various wavelengths across the visible region. The best spectral resolution is ∼12 cm{sup −1}. By tuning the pump wavelength closer to the electronic absorption band of a photoacid pyranine in water, we observe the pre-resonantly enhanced Raman signal. The stimulated Raman gain of the 1627 cm{sup −1} mode is increased by over 15 times.

  2. Visible and Near-infrared Light Curves of SN 2009nr

    NASA Astrophysics Data System (ADS)

    Heath, Jonathan; Bryngelson, Ginger

    2014-03-01

    This study explores the behavior of SN 2009nr, an apparently normal type Ia supernova (SN Ia). A plot of this object's brightness over time is known as a light curve. Because of the uniformity of their light curves, SNe Ia are valuable markers for determining the expansion of the universe and other cosmological parameters. Understanding the properties of these supernovae is vital in order to build our confidence in their use as standard candles. A small, but increasing number of SN Ia late-time observations have been made in the near-infrared (NIR). Most exhibit a flattening of the NIR power even as the visible light declines at a steady rate. It is still unclear as to why they exhibit this behavior and how typical this is. In order to characterize the late behavior of SNe Ia, images of SN 2009nr were analyzed using the Image Reduction and Analysis Facility (IRAF). NIR (J, H, K) images were taken with the 4m Mayall Telescope at Kitt Peak National-Observatory using the FLAMINGOS IR Imaging Spectrometer while visible (B, V, R, I) images used the Mosaic 1 imager. The supernova's apparent magnitude for each night of observation (by filter) was found by using reference stars. We present preliminary light curves of SN 2009nr and a comparison to another SN observed at similar epochs.

  3. Vibrational energy flow in photoactive yellow protein revealed by infrared pump-visible probe spectroscopy.

    PubMed

    Nakamura, Ryosuke; Hamada, Norio

    2015-05-14

    Vibrational energy flow in the electronic ground state of photoactive yellow protein (PYP) is studied by ultrafast infrared (IR) pump-visible probe spectroscopy. Vibrational modes of the chromophore and the surrounding protein are excited with a femtosecond IR pump pulse, and the subsequent vibrational dynamics in the chromophore are selectively probed with a visible probe pulse through changes in the absorption spectrum of the chromophore. We thus obtain the vibrational energy flow with four characteristic time constants. The vibrational excitation with an IR pulse at 1340, 1420, 1500, or 1670 cm(-1) results in ultrafast intramolecular vibrational redistribution (IVR) with a time constant of 0.2 ps. The vibrational modes excited through the IVR process relax to the initial ground state with a time constant of 6-8 ps in parallel with vibrational cooling with a time constant of 14 ps. In addition, upon excitation with an IR pulse at 1670 cm(-1), we observe the energy flow from the protein backbone to the chromophore that occurs with a time constant of 4.2 ps. PMID:25896223

  4. Oscillation wavelength shifts of visible and infrared laser diodes in a magnetic field

    NASA Astrophysics Data System (ADS)

    Sato, Takashi; Matsumoto, Kouichi; Toujou, Shin-ya; Nakagawa, Takayuki; Nakano, Hiroyuki; Ohkawa, Masashi; Maruyama, Takeo; Shimba, Minoru

    1998-10-01

    The shift, which occurs in the oscillation wavelength of a semiconductor laser in a magnetic field, has been the subject of great interest, since the early 60's. During the course of the investigation, the observed shift was toward the short wavelength side, i.e., a blue shift, which was well accounted for, in terms of the Landau level. At present, we are studying how wavelength shift is affected, by applying, at room temperature, a relatively weak magnetic field, using recently developed visible and infrared diode lasers. By doing so, we have observed a red shift and a decrease in laser output-power, under a certain magnetic field conditions in its strength and direction. Since these two changes in wavelength and output power correspond to those observed at higher temperatures, we assumed that the orientation of the magnetic field affects current density in laser diodes. And then it alters temperatures around the active layer, which in turn influence oscillation wavelength and laser output-power. Also of note, was the fact that the red shift and the decrease in laser output-power occurred simultaneously, revealing an almost linear dependency on one another. This might possibly explain the heat, which developed as the result of applying the magnetic field. However, we recently observed an instance, in which visible MQW laser diodes did not exhibit this linear dependence. Because this phenomenon cannot be traced simply to the effects of heat, we are now examining it in terms of current-density alteration.

  5. Simultaneous real-time visible and infrared video with single-pixel detectors.

    PubMed

    Edgar, Matthew P; Gibson, Graham M; Bowman, Richard W; Sun, Baoqing; Radwell, Neal; Mitchell, Kevin J; Welsh, Stephen S; Padgett, Miles J

    2015-01-01

    Conventional cameras rely upon a pixelated sensor to provide spatial resolution. An alternative approach replaces the sensor with a pixelated transmission mask encoded with a series of binary patterns. Combining knowledge of the series of patterns and the associated filtered intensities, measured by single-pixel detectors, allows an image to be deduced through data inversion. In this work we extend the concept of a 'single-pixel camera' to provide continuous real-time video at 10 Hz , simultaneously in the visible and short-wave infrared, using an efficient computer algorithm. We demonstrate our camera for imaging through smoke, through a tinted screen, whilst performing compressive sampling and recovering high-resolution detail by arbitrarily controlling the pixel-binning of the masks. We anticipate real-time single-pixel video cameras to have considerable importance where pixelated sensors are limited, allowing for low-cost, non-visible imaging systems in applications such as night-vision, gas sensing and medical diagnostics.

  6. Comparison of visible and near infrared reflectance spectroscopy on fat to authenticate dietary history of lambs.

    PubMed

    Huang, Y; Andueza, D; de Oliveira, L; Zawadzki, F; Prache, S

    2015-11-01

    Since consumers are showing increased interest in the origin and method of production of their food, it is important to be able to authenticate dietary history of animals by rapid and robust methods used in the ruminant products. Promising breakthroughs have been made in the use of spectroscopic methods on fat to discriminate pasture-fed and concentrate-fed lambs. However, questions remained on their discriminatory ability in more complex feeding conditions, such as concentrate-finishing after pasture-feeding. We compared the ability of visible reflectance spectroscopy (Vis RS, wavelength range: 400 to 700 nm) with that of visible-near-infrared reflectance spectroscopy (Vis-NIR RS, wavelength range: 400 to 2500 nm) to differentiate between carcasses of lambs reared with three feeding regimes, using partial least square discriminant analysis (PLS-DA) as a classification method. The sample set comprised perirenal fat of Romane male lambs fattened at pasture (P, n = 69), stall-fattened indoors on commercial concentrate and straw (S, n = 55) and finished indoors with concentrate and straw for 28 days after pasture-feeding (PS, n = 65). The overall correct classification rate was better for Vis-NIR RS than for Vis RS (99.0% v. 95.1%, P < 0.05). Vis-NIR RS allowed a correct classification rate of 98.6%, 100.0% and 98.5% for P, S and PS lambs, respectively, whereas Vis RS allowed a correct classification rate of 98.6%, 94.5% and 92.3% for P, S and PS lambs, respectively. This study suggests the likely implication of molecules absorbing light in the non-visible part of the Vis-NIR spectra (possibly fatty acids), together with carotenoid and haem pigments, in the discrimination of the three feeding regimes.

  7. TWINKLE – A Low Earth Orbit Visible and Infrared Exoplanet Spectroscopy Observatory

    NASA Astrophysics Data System (ADS)

    Tessenyi, Marcell; Savini, Giorgio; Tinetti, Giovanna; Tennyson, Jonathan; Dhesi, Mekhi; Joshua, Max

    2016-10-01

    Twinkle is a space mission designed for visible and near-IR spectroscopic observations of extrasolar planets. Twinkle's highly stable instrument will allow the photometric and spectroscopic observation of a wide range of planetary classes around different types of stars, with a focus on bright sources close to the ecliptic. The planets will be observed through transit and eclipse photometry and spectroscopy, as well as phase curves, eclipse mapping and multiple narrow-band time-series. The targets observed by Twinkle will be composed of known exoplanets mainly discovered by existing and upcoming ground surveys in our galaxy and will also feature new discoveries by space observatories (K2, GAIA, Cheops, TESS).Twinkle is a small satellite with a payload designed to perform high-quality astrophysical observations while adapting to the design of an existing Low Earth Orbit commercial satellite platform. The SSTL-300 bus, to be launched into a low-Earth sun-synchronous polar orbit by 2019, will carry a half-meter class telescope with two instruments (visible and near-IR spectrographs - between 0.4 and 4.5µm - with resolving power R~300 at the lower end of the wavelength scale) using mostly flight proven spacecraft systems designed by Surrey Satellite Technology Ltd and a combination of high TRL instrumentation and a few lower TRL elements built by a consortium of UK institutes.The Twinkle design will enable the observation of the chemical composition and weather of at least 100 exoplanets in the Milky Way, including super-Earths (rocky planets 1-10 times the mass of Earth), Neptunes, sub-Neptunes and gas giants like Jupiter. It will also allow the follow-up photometric observations of 1000+ exoplanets in the visible and infrared, as well as observations of Solar system objects, bright stars and disks.

  8. An infrared high resolution silicon immersion grating spectrometer for airborne and space missions

    NASA Astrophysics Data System (ADS)

    Ge, Jian; Zhao, Bo; Powell, Scott; Jiang, Peng; Uzakbaiuly, Berik; Tanner, David

    2014-08-01

    Broad-band infrared (IR) spectroscopy, especially at high spectral resolution, is a largely unexplored area for the far IR (FIR) and submm wavelength region due to the lack of proper grating technology to produce high resolution within the very constrained volume and weight required for space mission instruments. High resolution FIR spectroscopy is an essential tool to resolve many atomic and molecular lines to measure physical and chemical conditions and processes in the environments where galaxy, star and planets form. A silicon immersion grating (SIG), due to its over three times high dispersion over a traditional reflective grating, offers a compact and low cost design of new generation IR high resolution spectrographs for space missions. A prototype SIG high resolution spectrograph, called Florida IR Silicon immersion grating spectromeTer (FIRST), has been developed at UF and was commissioned at a 2 meter robotic telescope at Fairborn Observatory in Arizona. The SIG with 54.74 degree blaze angle, 16.1 l/mm groove density, and 50x86 mm2 grating area has produced R=50,000 in FIRST. The 1.4-1.8 um wavelength region is completely covered in a single exposure with a 2kx2k H2RG IR array. The on-sky performance meets the science requirements for ground-based high resolution spectroscopy. Further studies show that this kind of SIG spectrometer with an airborne 2m class telescope such as SOFIA can offer highly sensitive spectroscopy with R~20,000-30,000 at 20 to 55 microns. Details about the on-sky measurement performance of the FIRST prototype SIG spectrometer and its predicted performance with the SOFIA 2.4m telescope are introduced.

  9. Assessing stream temperature variation in the Pacific Northwest using airborne thermal infrared remote sensing.

    PubMed

    Tan, Jing; Cherkauer, Keith A

    2013-01-30

    The objective of this paper is to evaluate the temporal and spatial variability of stream temperatures and how stream temperatures are affected by land use through the use of airborne thermal infrared (TIR) imagery. Both five-meter and fifteen-meter MODIS/ASTER (MASTER) imagery were acquired along the main channel of the Green-Duwamish River in Washington State, U.S. in multiple straight line passes with image overlaps occurring at time intervals of between 3 and 45 min. Five- and fifteen-meter data were collected on August 25th, 2001, with a few additional five-meter images collected on August 27th. Image overlaps were studied to evaluate the time dependence between acquisition time and observed water temperature. Temperature change between adjacent images over the course of a few minutes was found to be negligible, but became significant at times greater than 45 min, with an estimated increase in water temperature of 2-3 °C between the first and last image collected for the complete five-meter resolution survey. Images captured from different days help identify persistent localized temperature differences. While accounting for temperature changes that occurred during the acquisition process, we still found that average stream reach temperatures increased with urbanization, while variability decreased. The same occurred in the immediate presence of a reservoir. This study suggests that urbanization affects stream temperature not only through the removal of riparian zone vegetation, but also through changes to sources in in-stream variability including the presence of rocks, woody debris and sandbars.

  10. Design considerations for a compact infrared airborne imager to meet alignment and assembly requirements

    NASA Astrophysics Data System (ADS)

    Spencer, Harvey

    2002-09-01

    Helicopter mounted optical systems require compact packaging, good image performance (approaching the diffraction-limit), and must survive and operate in a rugged shock and thermal environment. The always-present requirement for low weight in an airborne sensor is paramount when considering the optical configuration. In addition, the usual list of optical requirements which must be satisfied within narrow tolerances, including field-of-view, vignetting, boresight, stray light rejection, and transmittance drive the optical design. It must be determined early in the engineering process which internal optical alignment adjustment provisions must be included, which may be included, and which will have to be omitted, since adding alignment features often conflicts with the requirement for optical component stability during operation and of course adds weight. When the system is to be modular and mates with another optical system, a telescope designed by different contractor in this case, additional alignment requirements between the two systems must be specified and agreed upon. Final delivered cost is certainly critical and "touch labor" assembly time must be determined and controlled. A clear plan for the alignment and assembly steps must be devised before the optical design can even begin to ensure that an arrangement of optical components amenable to adjustment is reached. The optical specification document should be written contemporaneously with the alignment plan to insure compatibility. The optics decisions that led to the success of this project are described and the final optical design is presented. A description of some unique pupil alignment adjustments, never performed by us in the infrared, is described.

  11. An airborne spectrometer with three infrared lasers for trace gas measurements applied to convection case studies

    NASA Astrophysics Data System (ADS)

    Catoire, V.; Krysztofiak, G.; Robert, C.; Chartier, M.

    2012-12-01

    An infrared absorption spectrometer named SPIRIT (SPectromètre InfraRouge In situ Toute altitude) has been built for airborne simultaneous online measurements of trace gases. SPIRIT is based on two recent technological advances, leading to optimal performances and miniaturization: continuous wave quantum cascade lasers (CW-QCL) operating near room temperature coupled to a new, patented, multipass optical cell (Robert, Appl. Optics, 2007). An essential electronic development allows the sequential use of three QCLs with the same single cell. With judicious selected spectral micro-windows, this potentially leads to the measurements of at least four species at 0.7 Hz frequency. The first deployment of SPIRIT was made onboard the DLR Falcon-20 aircraft during the campaign associated to the EU SHIVA (Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere) project in Nov.-Dec. 2011 over Malaysia. In the present paper, the flight of 19 Nov. is presented in detail as an example of the SPIRIT performances, with CO, CO2, CH4 and N2O as measured species. The aircraft crossed four times the anvil of a severe thunderstorm from 11.3 km to 12.8 km altitude corresponding to a large convective system near Borneo island (6.0°N-115.5°E). During the crossing, carbon monoxide mixing ratios increase by 5 to 10 ppbv from the ambient cloud free environment to the anvil cloud correlated with an increase of CH4 mixing ratio. Using these observations, the fraction of boundary layer air contained in fresh convective outflow has been calculated. Other convection cases were detected, allowing for other fractions to be calculated, with results ranging between 0.15 and 0.55 and showing the variability of the mixing taking place during convective transport.

  12. Selective tumor imaging by a novel tumor specific aralin-infrared-to-visible phosphor conjugate

    NASA Astrophysics Data System (ADS)

    Kawasaki, Y.; Gotoh, Y.; Tokuzen, K.; Kamimura, M.; Komeno, T.; Tomatsu, M.; Todoroki, R.; Nagasaki, Y.; Soga, K.; Tashiro, F.

    2009-11-01

    Aralin is a novel cytotoxic protein from Aralia elata and selectively induces apoptosis in transformed cells as compared to normal cells (1). Aralin is a lectin specific for sugar chain such as galactose and possesses RNA N-glycosidase activity. In this study, antitumor potency of aralin was analyzed using the poly(ethyleneglycol) (PEG)/streptavidin co-immobilized infrared-to-visible upconversion phosphors, Y2O3 nanoparticles (2). Cy3-conjugated aralin could clearly detect the surface of SV40-transformed VA13 and human cervical carcinoma HeLa cells, but to a lesser extent on the normal human fibroblast WI-38 cells. Conjugation of aralin with PEGylated Y2O3 nanophosphor was carried out via biotin-avidin binding. The Y2O3-conjugated aralin also clearly visualize by a fluorescence microscope measurements equipped with near-infrared excitation source scanning in HeLa cells. It is also important to note that no remarkable damage to the cells was observed during these observations. Thus, these data imply that the Y2O3-conjugated aralin would potentially be useful material for tumor detection in vivo.

  13. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    SciTech Connect

    Medley, S.S.; Dimock, D.L.; Hayes, S.; Long, D.; Lowrence, J.L.; Mastrocola, V.; Renda, G.; Ulrickson, M.; Young, K.M.

    1985-05-01

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diameter fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (5/sup 0/, 20/sup 0/, and 60/sup 0/ field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35 mm Nikon F3 still camera, or (5) a 16 mm Locam II movie camera with variable framing up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented.

  14. Determination of geographical origin of alcoholic beverages using ultraviolet, visible and infrared spectroscopy: A review.

    PubMed

    Uríčková, Veronika; Sádecká, Jana

    2015-09-01

    The identification of the geographical origin of beverages is one of the most important issues in food chemistry. Spectroscopic methods provide a relative rapid and low cost alternative to traditional chemical composition or sensory analyses. This paper reviews the current state of development of ultraviolet (UV), visible (Vis), near infrared (NIR) and mid infrared (MIR) spectroscopic techniques combined with pattern recognition methods for determining geographical origin of both wines and distilled drinks. UV, Vis, and NIR spectra contain broad band(s) with weak spectral features limiting their discrimination ability. Despite this expected shortcoming, each of the three spectroscopic ranges (NIR, Vis/NIR and UV/Vis/NIR) provides average correct classification higher than 82%. Although average correct classification is similar for NIR and MIR regions, in some instances MIR data processing improves prediction. Advantage of using MIR is that MIR peaks are better defined and more easily assigned than NIR bands. In general, success in a classification depends on both spectral range and pattern recognition methods. The main problem still remains the construction of databanks needed for all of these methods.

  15. [Quality Analysis of Peanut Seed by Visible/Near-Infrared Spectra].

    PubMed

    Zheng, Tian-tian; Sun, Teng-fei; Cao, Zeng-hui; Zhang, Jun

    2015-03-01

    In this paper, three representative varieties of peanut seeds were selected for the experiment based on visible/near-infrared reflectance spectroscopy living in the wavelength rang from 600 to 1 100 nm. Firstly, spectral datas ware collected by the near-infrared fiber optic spectrometer, and the spectral features of the original spectral dates were extracted by the wavelet analysis. Then the principal component analysis (PCA) was used for cluster analysis of spectral features. Finally, the four principal components were applied as the inputs, the varieties category as the output and the Mahalanobis distance as the discriminant function of the recognition model, so a linear discriminant analysis model was established. In the 50 samples of each varieties, 30 samples were randomly selected as the training set, and the remaining 20 samples as the predictor set. The recognition model for three peanut varieties have a recognition rate of 95% on average. As the experimental results show that this method is reliable and effectively, and a new method to distinguish and discriminate the quality of peanut seeds was put forword.

  16. Determination of geographical origin of alcoholic beverages using ultraviolet, visible and infrared spectroscopy: A review

    NASA Astrophysics Data System (ADS)

    Uríčková, Veronika; Sádecká, Jana

    2015-09-01

    The identification of the geographical origin of beverages is one of the most important issues in food chemistry. Spectroscopic methods provide a relative rapid and low cost alternative to traditional chemical composition or sensory analyses. This paper reviews the current state of development of ultraviolet (UV), visible (Vis), near infrared (NIR) and mid infrared (MIR) spectroscopic techniques combined with pattern recognition methods for determining geographical origin of both wines and distilled drinks. UV, Vis, and NIR spectra contain broad band(s) with weak spectral features limiting their discrimination ability. Despite this expected shortcoming, each of the three spectroscopic ranges (NIR, Vis/NIR and UV/Vis/NIR) provides average correct classification higher than 82%. Although average correct classification is similar for NIR and MIR regions, in some instances MIR data processing improves prediction. Advantage of using MIR is that MIR peaks are better defined and more easily assigned than NIR bands. In general, success in a classification depends on both spectral range and pattern recognition methods. The main problem still remains the construction of databanks needed for all of these methods.

  17. Surface modification of organic polymer by dual action of extreme ultraviolet/visible-near infrared ultrashort pulses

    NASA Astrophysics Data System (ADS)

    Mocek, T.; Polan, J.; Homer, P.; Jakubczak, K.; Rus, B.; Kim, I. J.; Kim, C. M.; Lee, G. H.; Nam, C. H.; Hájková, V.; Chalupský, J.; Juha, L.

    2009-01-01

    We present the experimental evidence of structural surface modifications of poly(methyl methacrylate) (PMMA) caused by simultaneous action of extreme ultraviolet (XUV) (˜21 nm) and visible-near infrared (visible-NIR) (820/410 nm) ultrashort pulses. Although the fluence of each individual beam was far below the surface modification threshold, very efficient and specific material expansion was observed after irradiation of PMMA by more than ˜20 shots of mixed XUV/visible-NIR radiation. As the XUV photons generate free charge carriers, absorption of the optical radiation dramatically increases, which heats up the material and further enhances the XUV induced damage to the polymer chain.

  18. Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared

    SciTech Connect

    Gavel, D.T.; Morris, J.R. ); Vernon, R.G. )

    1992-08-01

    We are building an adaptive-optic telescope system that is based on the use of an artificial guide star created by laser-induced fluorescence of the sodium mesospheric layer. This paper discusses the system design for mid-visible to near-infrared compensation of a one meter telescope at Livermore and near-infrared compensation of the ten meter Keck telescope at Mauna Kea. We calculate the expected Strehl ratio and resolution for a 69 channel deformable mirror system and also for a possible 24 channel system upgrade. With the 69 actuator system we expect near diffraction limited resolution, about 0.2 arcsec, with a Strehl ratio of about 0.5 at {gamma}=0.8 {mu}m on the 1m telescope, and resolution of about 0.05 arcsec with a Strehl ratio of about 0.5 at {gamma}=2.0 {mu}m on the 10m telescope. Resolution will be limited by the performance of the tip/tilt correction loop, which uses an off-axis natural guide star as a reference. At Livermore, our design uses an existing high power (1 kW) laser source, which is expected to provide an approximately 6th magnitude artificial guide star. This strong beacon signal allows a short integration time in the wavefront sensor so that temporal changes in the atmospheric turbulence can be tracked accurately. For Mauna Kea, we explore how the system to be built for the Livermore site would perform in the infrared, assuming a 100 W laser source.

  19. Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared

    SciTech Connect

    Gavel, D.T.; Morris, J.R. ); Vernon, R.G. )

    1992-03-01

    We are building an adaptive-optic telescope system that is based on the use of an artificial guide star created by laser-induced fluorescence of the sodium mesospheric layer. This paper discusses the system design for mid-visible to near-infrared compensation of a one meter telescope at Livermore and near-infrared compensation of the ten meter Keck telescope at Mauna Kea. We calculate the expected Strehl ratio and resolution for a 69 channel deformable mirror system and also for a possible 241 channel system upgrade. With the 69 actuator system we expect near diffraction limited resolution, about 0.2 arcsec, with a Strehl ratio of about 0.5 at [lambda]=0.8,[mu]m on the 1m telescope, and resolution of about 0.05 arcsec with a Strehl ratio of about 0.5 at [lambda]=2.0 [mu]m on the 10m telescope. Resolution will be limited by the performance of the tip/tilt correction loop, which uses an off-axis natural guide star as a reference. The effects which degrade tip/tilt correction are described in a companion paper. At Livermore, our design uses an existing high power (1 kW) laser source, which is expected to provide an approximately 6'th magnitude artificial guide star. This strong beacon signal allows a short integration time in the wavefront sensor so that temporal changes in the atmospheric turbulence can be tracked accurately. For Mauna Kea, we explore how the system to be built for the Livermore site would perform in the infrared, assuming a 100 W laser source.

  20. Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared

    SciTech Connect

    Gavel, D.T.; Morris, J.R.; Vernon, R.G.

    1992-03-01

    We are building an adaptive-optic telescope system that is based on the use of an artificial guide star created by laser-induced fluorescence of the sodium mesospheric layer. This paper discusses the system design for mid-visible to near-infrared compensation of a one meter telescope at Livermore and near-infrared compensation of the ten meter Keck telescope at Mauna Kea. We calculate the expected Strehl ratio and resolution for a 69 channel deformable mirror system and also for a possible 241 channel system upgrade. With the 69 actuator system we expect near diffraction limited resolution, about 0.2 arcsec, with a Strehl ratio of about 0.5 at {lambda}=0.8,{mu}m on the 1m telescope, and resolution of about 0.05 arcsec with a Strehl ratio of about 0.5 at {lambda}=2.0 {mu}m on the 10m telescope. Resolution will be limited by the performance of the tip/tilt correction loop, which uses an off-axis natural guide star as a reference. The effects which degrade tip/tilt correction are described in a companion paper. At Livermore, our design uses an existing high power (1 kW) laser source, which is expected to provide an approximately 6`th magnitude artificial guide star. This strong beacon signal allows a short integration time in the wavefront sensor so that temporal changes in the atmospheric turbulence can be tracked accurately. For Mauna Kea, we explore how the system to be built for the Livermore site would perform in the infrared, assuming a 100 W laser source.

  1. Regional Sediment Management Experiment Using the Visible/Infrared Imager/Radiometer Suite and the Landsat Data Continuity Mission Sensor

    NASA Technical Reports Server (NTRS)

    Estep, Leland; Spruce, Joseph P.

    2007-01-01

    The central aim of this RPC (Rapid Prototyping Capability) experiment is to demonstrate the use of VIIRS (Visible/Infrared Imager/ Radiometer Suite and LDCM (Landsat Data Continuity Mission) sensors as key input to the RSM (Regional Sediment Management) GIS (geographic information system) DSS (Decision Support System). The project affects the Coastal Management National Application.

  2. Shelf life study of egg albumin in pasteurized and non-pasteurized eggs using visible-near infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A twelve week shelf life study was conducted on the egg albumen from both pasteurized and non-pasteurized shell eggs using visible-near infrared spectroscopy. The goal of the study was to correlate the chemical changes detected in the spectra to the measurement of Haugh units (measure of interior eg...

  3. Development of a system for classification of pork loins for tenderness using visible and near-infrared reflectance spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Boneless pork loins (n = 901) were evaluated either on the loin boning and trimming line of large-scale commercial plants (n = 465) or at the U.S. Meat Animal Research Center abattoir (n = 436). Exposed LM on the ventral side of boneless loins was evaluated with visible and near-infrared spectrosco...

  4. Comparison of optimal wavelengths selection methods for visible/near-infrared prediction of apple firmness and soluble solids content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visible and near-infrared (Vis-NIR) spectroscopy is now being used for nondestructive quality measurement of fruits and other food products. To implement the technology, it is necessary to develop an effective calibration model relating the acquired spectral data to the quality attribute(s) of inter...

  5. Implementing Metal-to-Ligand Charge Transfer in Organic Semiconductor for Improved Visible-Near-Infrared Photocatalysis.

    PubMed

    Li, Yanrui; Wang, Zhaowu; Xia, Tong; Ju, Huanxin; Zhang, Ke; Long, Ran; Xu, Qian; Wang, Chengming; Song, Li; Zhu, Junfa; Jiang, Jun; Xiong, Yujie

    2016-08-01

    The coordination of organic semiconductors with metal cations can induce metal-to-ligand charge transfer, which broadens light absorption to cover the visible-near-infrared (vis-NIR) spectrum. As a proof-of-concept demonstration, the g-C3 N4 -based complex exhibits dramatically enhanced photocatalytic H2 production with excellent durability under vis-NIR irradiation.

  6. Structure-Optical Property Correlations of Arsenic Sulfide Glasses in Visible, Infrared, and Sub-millimeter Regions

    SciTech Connect

    McCloy, John S.; Riley, Brian J.; Sundaram, S. K.; Qiao, Hong; Crum, Jarrod V.; Johnson, Bradley R.

    2010-06-01

    Optical properties and structural aspects of AsxS100-x glasses from visible to terahertz wavelengths were explored. A series of annealed, bulk AsxS100-x glasses (x = 30 to 42) were made and their refractive indices determined at terahertz, infrared, and visible frequencies using a combination of a quasi-optical backwards wave oscillator spectrometer for terahertz measurements and a prism coupler for visible and infrared measurements. It was found that refractive index at all frequencies increases with arsenic composition up to 40 atomic % arsenic then decreases with additional arsenic. Structure in x-ray diffraction patterns support the notion of a minimum volume at 40 atomic %, while the average covalent coordination number indicates the rigidity percolation threshold is reached there. At As concentrations > 40 atomic %, the network becomes over-constrained, the molar volume increases.

  7. Application of infrared radiometers for airborne detection of clear air turbulence and low level wind shear, airborne infrared low level wind shear detection test

    NASA Technical Reports Server (NTRS)

    Kuhn, P. M.

    1985-01-01

    The feasibility of infrared optical techniques for the advance detection and avoidance of low level wind shear (LLWS) or low altitude wind shear hazardous to aircraft operations was investigated. A primary feasibility research effort was conducted with infrared detectors and instrumentation aboard the NASA Ames Research Center Learjet. The main field effort was flown on the NASA-Ames Dryden B57B aircraft. The original approach visualized a forward-looking, infrared transmitting (KRS-5) window through which signals would reach the detector. The present concept of a one inch diameter light pipe with a 45 deg angled mirror enables a much simpler installation virtually anywhere on the aircraft coupled with the possibility of horizontal scanning via rotation of the forward directed mirror. Present infrared detectors and filters would certainly permit ranging and horizontal scanning in a variety of methods. CRT display technology could provide a contoured picture with possible shear intensity levels from the infrared detection system on the weather radar or a small adjunct display. This procedure shoud be further developed and pilot evaluated in a light aircraft such as a Cessna 207 or equivalent.

  8. Visible and Mid-Infrared Gypsum Optical Constants for Modeling of Martian Deposits

    NASA Astrophysics Data System (ADS)

    Roush, Ted L.; Esposito, Francesca; Rossmann, George R.; Colangeli, Luigi

    2007-08-01

    Introduction: Recent and on-going remote and in situ observations indicate that sulfates are present in significant abundances at various locations on Mars [1-7]. The Mars Reconnaissance Orbiter (MRO) imaging spectrometer (CRISM) is returning hyperspectral data at higher spatial resolution [8] than the OMEGA instrument on the Mars Express Mission [3]. Data from both OMEGA and CRISM have provided spectral evidence for the presence of gypsum and various hydrated sulfates on the Martian surface [e.g. 3-7] Thus, the optical properties of sulfates, in general, are of interest to quantitative interpretation of this increasing volume of remotely sensed data. This is because optical constants describe how a material interacts with electromagnetic radiation and represent the fundamental values used in radiative transfer calculations describing a variety of physical environments. Such environments include atmospheres where aerosols are present, planetary and satellite regoliths, and circumstellar dust clouds. Here we focus upon gypsum because of its applicability due to its identification on Mars. Also, gypsum is a mineral that is readily available in samples sizes that are suitable for study using a variety of spectral measurements. In the infrared (>5 μm) several studies reporting the optical constants of gypsum can be used in evaluating the approach used here. Most importantly, there is a general lack of data regarding the optical constants for gypsum at visible and mid-infrared wavelengths (0.4-5 μm) that are being observed by OMEGA and CRISM. Background: In the infrared, there have been several studies focused at determining the optical constants of gypsum using classical dispersion models [9-11]. These have used a variety of samples including; crystals, compressed pellets of pure materials, and grains suspended in a KBr matrix. Spectral measurements of gypsum, and other sulfates, have existed for about 100 years at visible and mid-infrared wavelengths (0.4-5 μm) [e

  9. Summaries of the Sixth Annual JPL Airborne Earth Science Workshop. Volume 1; AVIRIS Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O. (Editor)

    1996-01-01

    This publication contains the summaries for the Sixth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on March 4-8, 1996. The main workshop is divided into two smaller workshops as follows: (1) The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on March 4-6. The summaries for this workshop appear in Volume 1; (2) The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on March 6-8. The summaries for this workshop appear in Volume 2.

  10. Ion irradiation of the Murchison meteorite: Visible to mid-infrared spectroscopic results

    NASA Astrophysics Data System (ADS)

    Lantz, C.; Brunetto, R.; Barucci, M. A.; Dartois, E.; Duprat, J.; Engrand, C.; Godard, M.; Ledu, D.; Quirico, E.

    2015-05-01

    Aims: The goal of this study is to simulate space weathering processes on primitive bodies. We use ion implantation as a simulation of solar wind irradiation, which has been suggested by several authors to be the major component of space weathering on main belt asteroids. The laboratory analogs we irradiate and analyze are carbonaceous chondrites; we started the study with the Allende CV meteorite and in this companion paper we present results on the Murchison CM meteorite. Methods: We performed irradiations on pressed pellets of Murchison with 40 keV He+ and Ar+ ions using fluences up to 3 × 1016 ions/cm2. Reflectance spectra were acquired ex situ before and after irradiation in the visible to mid-infrared range (0.4-16 μm). A Raman analysis was also performed to investigate the modifications of the aromatic carbonaceous component. Results: Our results indicate that spectral variations after irradiation within the visible range are smaller than spectral variations due to sample grain size or viewing geometry of the Murchison meteorite. The aqueous alteration band profile near 3 μm changes after irradiation, as adsorbed water is removed, and phyllosilicates are affected. Raman spectroscopy highlights the insoluble organic matter (IOM) modification under irradiation. We observe a shift of the silicates band at 9.9 μm, probably due to a preferential loss of Mg (compared to Fe, the lighter Mg is more easily sputtered backward) and/or amorphization of Mg-rich materials. We compare our results to previous experiments on organic-rich materials (like asphaltite or carbonaceous chondrites), and on ordinary chondrites and olivine grains. We find that the reddening/darkening trend observed on silicate-rich surfaces is not valid for all carbonaceous chondrites, and that the spectral modifications after irradiation are a function of the initial albedo.

  11. An infrared astronomer's early vision of airborne astronomy: Paul Merrill 1920

    NASA Technical Reports Server (NTRS)

    Osterbrock, Donald E.

    1995-01-01

    The first published paper by a professional, research astronomer which discussed airborne astronomy from airplanes was by Paul W. Merrill. In it he proposed some of the types of observations which might be made, looking up at astronomical objects in the sky. This paper describes Merrill's paper, his education, training and subsequent career, and a few other aspects of the early history of airborne astronomy.

  12. Visible and near-infrared bulk optical properties of raw milk.

    PubMed

    Aernouts, B; Van Beers, R; Watté, R; Huybrechts, T; Lammertyn, J; Saeys, W

    2015-10-01

    The implementation of optical sensor technology to monitor the milk quality on dairy farms and milk processing plants would support the early detection of altering production processes. Basic visible and near-infrared spectroscopy is already widely used to measure the composition of agricultural and food products. However, to obtain maximal performance, the design of such optical sensors should be optimized with regard to the optical properties of the samples to be measured. Therefore, the aim of this study was to determine the visible and near-infrared bulk absorption coefficient, bulk scattering coefficient, and scattering anisotropy spectra for a diverse set of raw milk samples originating from individual cow milkings, representing the milk variability present on dairy farms. Accordingly, this database of bulk optical properties can be used in future simulation studies to efficiently optimize and validate the design of an optical milk quality sensor. In a next step of the current study, the relation between the obtained bulk optical properties and milk quality properties was analyzed in detail. The bulk absorption coefficient spectra were found to mainly contain information on the water, fat, and casein content, whereas the bulk scattering coefficient spectra were found to be primarily influenced by the quantity and the size of the fat globules. Moreover, a strong positive correlation (r ≥ 0.975) was found between the fat content in raw milk and the measured bulk scattering coefficients in the 1,300 to 1,400 nm wavelength range. Relative to the bulk scattering coefficient, the variability on the scattering anisotropy factor was found to be limited. This is because the milk scattering anisotropy is nearly independent of the fat globule and casein micelle quantity, while it is mainly determined by the size of the fat globules. As this study shows high correlations between the sample's bulk optical properties and the milk composition and fat globule size, a

  13. Physical Properties of Volcanic Material (Tephra) Using Visible Near-Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Necsoiu, M.; Hooper, D.; Roseberry, J.

    2007-12-01

    Sunset Crater, Arizona, offers the opportunity to investigate the relationship between visible near-infrared reflectance and physical properties of volcanic material as related to the evolution of a 900-year-old tephra deposit in a semiarid climate. This is an analog area for latent eruption and posteruption surface processes near the potential high-level waste repository at Yucca Mountain, Nevada. Quantitative and qualitative analyses were performed on tephra modified by eolian processes to investigate the effects of grain size, shape, texture, and weathering on spectral response. Reflectance spectra were collected from homogeneous sample splits separated by sieve fraction. Principal component analysis (PCA) was applied to decompose data by finding maximum variances, so the complexity of tephra samples could be easily interpreted. Partial least squares (PLS) was used for developing a linear calibration model between grain size and spectral reflectance of sieve fractions. The model was used to estimate grain-size distributions of other tephra samples collected from other locations in the study area. The trends observed in the spectral reflectance of these samples showed that a complex relationship exists between reflectance and geometry/grain size of the analyzed fractions. The first and second principal components were useful to separate the samples based on shape, texture, and the amount of weathering. As expected, the grain size of a homogeneous sample affects the reflectance properties such that an increase in grain size produces a decrease in reflectance. This trend is noticeable for grain-size sieve fractions less than 0.6 mm [0.02 in]. Through this research, we are improving our understanding of the relationships between physical properties and spectral response of volcanic material in the visible and near-infrared regions. These relationships are being used to support investigations of the extent of tephra deposit remobilization and redistribution

  14. Visible and near-infrared bulk optical properties of raw milk.

    PubMed

    Aernouts, B; Van Beers, R; Watté, R; Huybrechts, T; Lammertyn, J; Saeys, W

    2015-10-01

    The implementation of optical sensor technology to monitor the milk quality on dairy farms and milk processing plants would support the early detection of altering production processes. Basic visible and near-infrared spectroscopy is already widely used to measure the composition of agricultural and food products. However, to obtain maximal performance, the design of such optical sensors should be optimized with regard to the optical properties of the samples to be measured. Therefore, the aim of this study was to determine the visible and near-infrared bulk absorption coefficient, bulk scattering coefficient, and scattering anisotropy spectra for a diverse set of raw milk samples originating from individual cow milkings, representing the milk variability present on dairy farms. Accordingly, this database of bulk optical properties can be used in future simulation studies to efficiently optimize and validate the design of an optical milk quality sensor. In a next step of the current study, the relation between the obtained bulk optical properties and milk quality properties was analyzed in detail. The bulk absorption coefficient spectra were found to mainly contain information on the water, fat, and casein content, whereas the bulk scattering coefficient spectra were found to be primarily influenced by the quantity and the size of the fat globules. Moreover, a strong positive correlation (r ≥ 0.975) was found between the fat content in raw milk and the measured bulk scattering coefficients in the 1,300 to 1,400 nm wavelength range. Relative to the bulk scattering coefficient, the variability on the scattering anisotropy factor was found to be limited. This is because the milk scattering anisotropy is nearly independent of the fat globule and casein micelle quantity, while it is mainly determined by the size of the fat globules. As this study shows high correlations between the sample's bulk optical properties and the milk composition and fat globule size, a

  15. An infrared-visible image fusion scheme based on NSCT and compressed sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Qiong; Maldague, Xavier

    2015-05-01

    Image fusion, as a research hot point nowadays in the field of infrared computer vision, has been developed utilizing different varieties of methods. Traditional image fusion algorithms are inclined to bring problems, such as data storage shortage and computational complexity increase, etc. Compressed sensing (CS) uses sparse sampling without knowing the priori knowledge and greatly reconstructs the image, which reduces the cost and complexity of image processing. In this paper, an advanced compressed sensing image fusion algorithm based on non-subsampled contourlet transform (NSCT) is proposed. NSCT provides better sparsity than the wavelet transform in image representation. Throughout the NSCT decomposition, the low-frequency and high-frequency coefficients can be obtained respectively. For the fusion processing of low-frequency coefficients of infrared and visible images , the adaptive regional energy weighting rule is utilized. Thus only the high-frequency coefficients are specially measured. Here we use sparse representation and random projection to obtain the required values of high-frequency coefficients, afterwards, the coefficients of each image block can be fused via the absolute maximum selection rule and/or the regional standard deviation rule. In the reconstruction of the compressive sampling results, a gradient-based iterative algorithm and the total variation (TV) method are employed to recover the high-frequency coefficients. Eventually, the fused image is recovered by inverse NSCT. Both the visual effects and the numerical computation results after experiments indicate that the presented approach achieves much higher quality of image fusion, accelerates the calculations, enhances various targets and extracts more useful information.

  16. Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite Polarization Sensitivity Analysis

    NASA Technical Reports Server (NTRS)

    Sun, Junqiang; Xiong, Xiaoxiong; Waluschka, Eugene; Wang, Menghua

    2016-01-01

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of five instruments onboard the Suomi National Polar-Orbiting Partnership (SNPP) satellite that launched from Vandenberg Air Force Base, California, on October 28, 2011. It is a whiskbroom radiometer that provides +/-56.28deg scans of the Earth view. It has 22 bands, among which 14 are reflective solar bands (RSBs). The RSBs cover a wavelength range from 410 to 2250 nm. The RSBs of a remote sensor are usually sensitive to the polarization of incident light. For VIIRS, it is specified that the polarization factor should be smaller than 3% for 410 and 862 nm bands and 2.5% for other RSBs for the scan angle within +/-45deg. Several polarization sensitivity tests were performed prelaunch for SNPP VIIRS. The first few tests either had large uncertainty or were less reliable, while the last one was believed to provide the more accurate information about the polarization property of the instrument. In this paper, the measured data in the last polarization sensitivity test are analyzed, and the polarization factors and phase angles are derived from the measurements for all the RSBs. The derived polarization factors and phase angles are band, detector, and scan angle dependent. For near-infrared bands, they also depend on the half-angle mirror side. Nevertheless, the derived polarization factors are all within the specification, although the strong detector dependence of the polarization parameters was not expected. Compared to the Moderate Resolution Imaging Spectroradiometer on both Aqua and Terra satellites, the polarization effect on VIIRS RSB is much smaller.

  17. Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite polarization sensitivity analysis.

    PubMed

    Sun, Junqiang; Xiong, Xiaoxiong; Waluschka, Eugene; Wang, Menghua

    2016-09-20

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of five instruments onboard the Suomi National Polar-Orbiting Partnership (SNPP) satellite that launched from Vandenberg Air Force Base, California, on October 28, 2011. It is a whiskbroom radiometer that provides ±56.28° scans of the Earth view. It has 22 bands, among which 14 are reflective solar bands (RSBs). The RSBs cover a wavelength range from 410 to 2250 nm. The RSBs of a remote sensor are usually sensitive to the polarization of incident light. For VIIRS, it is specified that the polarization factor should be smaller than 3% for 410 and 862 nm bands and 2.5% for other RSBs for the scan angle within ±45°. Several polarization sensitivity tests were performed prelaunch for SNPP VIIRS. The first few tests either had large uncertainty or were less reliable, while the last one was believed to provide the more accurate information about the polarization property of the instrument. In this paper, the measured data in the last polarization sensitivity test are analyzed, and the polarization factors and phase angles are derived from the measurements for all the RSBs. The derived polarization factors and phase angles are band, detector, and scan angle dependent. For near-infrared bands, they also depend on the half-angle mirror side. Nevertheless, the derived polarization factors are all within the specification, although the strong detector dependence of the polarization parameters was not expected. Compared to the Moderate Resolution Imaging Spectroradiometer on both Aqua and Terra satellites, the polarization effect on VIIRS RSB is much smaller. PMID:27661594

  18. Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite polarization sensitivity analysis.

    PubMed

    Sun, Junqiang; Xiong, Xiaoxiong; Waluschka, Eugene; Wang, Menghua

    2016-09-20

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of five instruments onboard the Suomi National Polar-Orbiting Partnership (SNPP) satellite that launched from Vandenberg Air Force Base, California, on October 28, 2011. It is a whiskbroom radiometer that provides ±56.28° scans of the Earth view. It has 22 bands, among which 14 are reflective solar bands (RSBs). The RSBs cover a wavelength range from 410 to 2250 nm. The RSBs of a remote sensor are usually sensitive to the polarization of incident light. For VIIRS, it is specified that the polarization factor should be smaller than 3% for 410 and 862 nm bands and 2.5% for other RSBs for the scan angle within ±45°. Several polarization sensitivity tests were performed prelaunch for SNPP VIIRS. The first few tests either had large uncertainty or were less reliable, while the last one was believed to provide the more accurate information about the polarization property of the instrument. In this paper, the measured data in the last polarization sensitivity test are analyzed, and the polarization factors and phase angles are derived from the measurements for all the RSBs. The derived polarization factors and phase angles are band, detector, and scan angle dependent. For near-infrared bands, they also depend on the half-angle mirror side. Nevertheless, the derived polarization factors are all within the specification, although the strong detector dependence of the polarization parameters was not expected. Compared to the Moderate Resolution Imaging Spectroradiometer on both Aqua and Terra satellites, the polarization effect on VIIRS RSB is much smaller.

  19. Comparison of Two Methodologies for Calibrating Satellite Instruments in the Visible and Near Infrared

    NASA Technical Reports Server (NTRS)

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Xiong, Xiaoxiong (Jack); Butler, James J.

    2010-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance response in a two-step method. In the first step, the spectral response of the instrument is determined using a nearly monochromatic light source, such a lamp-illuminated monochromator. Such sources only provide a relative spectral response (RSR) for the instrument, since they do not act as calibrated sources of light nor do they typically fill the field-of-view of the instrument. In the second step, the instrument views a calibrated source of broadband light, such as lamp-illuminated integrating sphere. In the traditional method, the RSR and the sphere spectral radiance are combined and, with the instrument's response, determine the absolute spectral radiance responsivity of the instrument. More recently, an absolute calibration system using widely tunable monochromatic laser systems has been developed, Using these sources, the absolute spectral responsivity (ASR) of an instrument can be determined on a wavelength-hy-wavelength basis. From these monochromatic ASRs. the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. Here we describe the laser-based calibration and the traditional broad-band source-based calibration of the NPP VIIRS sensor, and compare the derived calibration coefficients for the instrument. Finally, we evaluate the impact of the new calibration approach on the on-orbit performance of the sensor.

  20. Altered rock spectra in the visible and near infrared. [western Nevada

    NASA Technical Reports Server (NTRS)

    Hunt, G. R.; Ashley, R. P. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. Visible and near-infrared (0.35 to 2.5 micron m) bidirectional reflection spectra recorded for a suite of well-characterized hydrothermally altered rock samples typically display well defined bands caused by both electronic and vibrational processes in the individual mineral constituents. Electronic transitions in the iron-bearing constituent minerals produce diagnostic minima near 0.43, 0.65, 0.85, and 0.93 micron m. Vibrational transitions in clay and water-bearing mineral constituents produce characteristic single or multiple features over limited spectral ranges near 1.4, 1.75, 1.9, 2.2, and 2.35 micron m. The most abundant feature-producing minerals present in these rocks are hematite, goethite, and alunite. Others frequently present are jarosite, kaolinite, potassium micas, pyrophyllite, montmorillonite, diaspore, and gypsum. The spectral region near 2.2 micron m is particularly important for detecting altered rocks by remote sensing.

  1. Discrimination between Sedimentary Rocks from Close-Range Visible and Very-Near-Infrared Images.

    PubMed

    Del Pozo, Susana; Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo; Kees Blom, Jan; González-Aguilera, Diego

    2015-01-01

    Variation in the mineral composition of rocks results in a change of their spectral response capable of being studied by imaging spectroscopy. This paper proposes the use of a low-cost handy sensor, a calibrated visible-very near infrared (VIS-VNIR) multispectral camera for the recognition of different geological formations. The spectral data was recorded by a Tetracam Mini-MCA-6 camera mounted on a field-based platform covering six bands in the spectral range of 0.530-0.801 µm. Twelve sedimentary formations were selected in the Rhône-Alpes region (France) to analyse the discrimination potential of this camera for rock types and close-range mapping applications. After proper corrections and data processing, a supervised classification of the multispectral data was performed trying to distinguish four classes: limestones, marlstones, vegetation and shadows. After a maximum-likelihood classification, results confirmed that this camera can be efficiently exploited to map limestone-marlstone alternations in geological formations with this mineral composition.

  2. Direct fusion of geostationary meteorological satellite visible and infrared images based on thermal physical properties.

    PubMed

    Han, Lei; Wulie, Buzha; Yang, Yiling; Wang, Hongqing

    2015-01-05

    This study investigated a novel method of fusing visible (VIS) and infrared (IR) images with the major objective of obtaining higher-resolution IR images. Most existing image fusion methods focus only on visual performance and many fail to consider the thermal physical properties of the IR images, leading to spectral distortion in the fused image. In this study, we use the IR thermal physical property to correct the VIS image directly. Specifically, the Stefan-Boltzmann Law is used as a strong constraint to modulate the VIS image, such that the fused result shows a similar level of regional thermal energy as the original IR image, while preserving the high-resolution structural features from the VIS image. This method is an improvement over our previous study, which required VIS-IR multi-wavelet fusion before the same correction method was applied. The results of experiments show that applying this correction to the VIS image directly without multi-resolution analysis (MRA) processing achieves similar results, but is considerably more computationally efficient, thereby providing a new perspective on VIS and IR image fusion.

  3. Time-resolved fluorescence polarization spectroscopy of visible and near infrared dyes in picosecond dynamics

    NASA Astrophysics Data System (ADS)

    Pu, Yang; Alfano, Robert R.

    2015-03-01

    Near-infrared (NIR) dyes absorb and emit light within the range from 700 to 900 nm have several benefits in biological studies for one- and/or two-photon excitation for deeper penetration of tissues. These molecules undergo vibrational and rotational motion in the relaxation of the excited electronic states, Due to the less than ideal anisotropy behavior of NIR dyes stemming from the fluorophores elongated structures and short fluorescence lifetime in picosecond range, no significant efforts have been made to recognize the theory of these dyes in time-resolved polarization dynamics. In this study, the depolarization of the fluorescence due to emission from rotational deactivation in solution will be measured with the excitation of a linearly polarized femtosecond laser pulse and a streak camera. The theory, experiment and application of the ultrafast fluorescence polarization dynamics and anisotropy are illustrated with examples of two of the most important medical based dyes. One is NIR dye, namely Indocyanine Green (ICG) and is compared with Fluorescein which is in visible range with much longer lifetime. A set of first-order linear differential equations was developed to model fluorescence polarization dynamics of NIR dye in picosecond range. Using this model, the important parameters of ultrafast polarization spectroscopy were identified: risetime, initial time, fluorescence lifetime, and rotation times.

  4. Highly sensitive visible to infrared MoTe2 photodetectors enhanced by the photogating effect.

    PubMed

    Huang, Hai; Wang, Jianlu; Hu, Weida; Liao, Lei; Wang, Peng; Wang, Xudong; Gong, Fan; Chen, Yan; Wu, Guangjian; Luo, Wenjin; Shen, Hong; Lin, Tie; Sun, Jinglan; Meng, Xiangjian; Chen, Xiaoshuang; Chu, Junhao

    2016-11-01

    Two-dimensional materials are promising candidates for electronic and optoelectronic applications. MoTe2 has an appropriate bandgap for both visible and infrared light photodetection. Here we fabricate a high-performance photodetector based on few-layer MoTe2. Raman spectral properties have been studied for different thicknesses of MoTe2. The photodetector based on few-layer MoTe2 exhibits broad spectral range photodetection (0.6-1.55 μm) and a stable and fast photoresponse. The detectivity is calculated to be 3.1 × 10(9) cm Hz(1/2) W(-1) for 637 nm light and 1.3 × 10(9) cm Hz(1/2) W(-1) for 1060 nm light at a backgate voltage of 10 V. The mechanisms of photocurrent generation have been analyzed in detail, and it is considered that a photogating effect plays an important role in photodetection. The appreciable performance and detection over a broad spectral range make it a promising material for high-performance photodetectors. PMID:27670378

  5. Assessment and mapping of soil nitrogen using Visible-Near-Infrared (Vis-NIR) spectra

    NASA Astrophysics Data System (ADS)

    Liu, Xiang; Guo, Yan; Wang, Qian-long; Zhang, Jian; Shi, Zhou

    2013-08-01

    Visible and near infrared (Vis-NIR) reflectance spectroscopy technology, which is rapid, cost-effective, in-situ and non-destructive, is getting more and more widely used in improving the prediction and digital mapping for soil properties. Soil available nitrogen (AN) is closely related to soil fertility and quality, assessing its content and mapping the spatial variability greatly satisfies precision agriculture. In this study, the Vis-NIR diffuse reflectance spectra collected by ASD FieldSpec Pro FR spectrometer with a performance of spectral range from 350 nm to 2500 nm, 1 nm resampling intervals, was used to model and characterize the spatial variability of available nitrogen. Firstly, the raw soil spectra was pre-processing by reducing to 400 nm - 2450 nm with transformation into apparent absorbance spectral using Log(1/R) and Savitzky-Golay smoothing. Secondly, spectral indices (normalized spectral index-NDI; difference index-DI; ratio index-RI) were convinced for seeking further relationship between AN. Afterwards, Partial Least Squares Regression (PLSR) method was employed to predict AN. The results indicated good predictions with RPD more than 1.4. Finally, the spatial variability of AN was mapped by (co)kriging method, digital mapping of the measured and predicted AN showed similar patterns and value ranges, though there are some minor differences. The resultant prediction and mapping demonstrated a promotion of assessing and mapping of soil properties by a rapid and reliable approach from lab to field in-situ.

  6. Optical system for tablet variety discrimination using visible/near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Shao, Yongni; He, Yong; Hu, Xingyue

    2007-12-01

    An optical system based on visible/near-infrared spectroscopy (Vis/NIRS) for variety discrimination of ginkgo (Ginkgo biloba L.) tablets was developed. This system consisted of a light source, beam splitter system, sample chamber, optical detector (diffuse reflection detector), and data collection. The tablet varieties used in the research include Da na kang, Xin bang, Tian bao ning, Yi kang, Hua na xing, Dou le, Lv yuan, Hai wang, and Ji yao. All samples (n=270) were scanned in the Vis/NIR region between 325 and 1075 nm using a spectrograph. The chemometrics method of principal component artificial neural network (PC-ANN) was used to establish discrimination models of them. In PC-ANN models, the scores of the principal components were chosen as the input nodes for the input layer of ANN, and the best discrimination rate of 91.1% was reached. Principal component analysis was also executed to select several optimal wavelengths based on loading values. Wavelengths at 481, 458, 466, 570, 1000, 662, and 400 nm were then used as the input data of stepwise multiple linear regression, the regression equation of ginkgo tablets was obtained, and the discrimination rate was researched 84.4%. The results indicated that this optical system could be applied to discriminating ginkgo (Ginkgo biloba L.) tablets, and it supplied a new method for fast ginkgo tablet variety discrimination.

  7. Visible and near infrared wavelength photonic crystal fiber splitter for multiwavelength spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Eom, Joo Beom; Min, Eun Jung; Lee, Byeong Ha

    2012-01-01

    We report the fabrication and performance of the 2×2 photonic crystal fiber (PCF) splitter that was designed as a single mode splitter at the visible and near infrared and used as the beam splitter for a spectral domain optical coherence tomography (SD-OCT) system. The PCF splitter has been made by coupling PCFs to a planar lightwave circuit (PLC) splitter chip. The PLC splitter chip was fabricated to have a single mode property with 630 nm cutoff wavelength and the PCFs were securely connected to the PLC chip through PCF block arrays having lithographically fabricated V grooves. The core width of the splitter chip was about 4 μm×4 μm and the core-cladding index difference was about 0.15%. With the implemented PCF PLC splitter, we have obtained a low excess loss of 1.2 dB and a low polarization-dependent loss of 0.19 dB at 680 nm with wide band coupling property. With the proposed 2×2 PCF splitter, SD-OCT images of human finger, nail, and tooth successfully obtained by using 680 nm, 840 nm, and 930 nm SLD source. This PCF PLC splitter is expected to have high resolution OCT.

  8. Visible and near-infrared spectroscopic survey of Jupiter Trojan asteroids: investigation of dynamical families

    NASA Astrophysics Data System (ADS)

    Dotto, E.; Fornasier, S.; Barucci, M. A.; Boehnhardt, H.; Hainaut, O.; Marzari, F.; Licandro, J.; de Bergh, C.

    2004-11-01

    Trojan asteroids located in the Jupiter Lagrangian points L4 and L5 (60 degrees ahead and behind Jupiter) are widely believed to be primordial bodies since their orbits are stable over the age of the Solar System. They seem to have been formed in a region of the solar nebula rich in frozen volatiles and to have never suffered selective induction heating. They probably still contain ices in their interiors.Moreover the discovery of several dynamical families among Trojans suggests that they are at least as collisionally evolved as the main asteroid belt. Since 2002, we started an observational program on Jupiter Trojans at ESO-NTT, ESO-VLT and TNG. In particular we concentrated on members of dynamical families, as defined by Beauge and Roig (2001), and we observed also several background objects. We carry out visible and near-infrared spectroscopy and photometry in order to i) characterize the mineralogical composition of families, ii) give evidence of ongoing space weathering, and iii) confirm family membership. As expected, the spectra of the non-family members are more heterogeneous compared to the spectra of family members. The obtained results will be presented and discussed.

  9. Infrared to visible magneto-optical effects in (Ga,Mn)As

    NASA Astrophysics Data System (ADS)

    Tesarova, N.; Ellis, C. T.; Acbas, G.; Mukherjee, A.; Vyborny, K.; Cerne, J.; Subrt, J.; Ostatnicky, T.; Nemec, P.; Novak, V.; Sinova, J.

    2012-02-01

    (Ga,Mn)As is perceived as a model material for future low-power spintronics devices due to its carrier mediated ferromagnetic properties. Despite the extensive theoretical and experimental studies, the energy band structure and the mechanism of ferromagnetic order (of Mn spins) still remains a matter of controversy [Ohya, Nature Physics 2011; Jungwirth, PRL 2010]. In our study, we employ magneto-optical Faraday and Kerr measurements to probe the character of the states near the Fermi energy, which is expected to be responsible for Mn-ordering. We also study the spectral dependence of magnetic linear dichroism that is mainly sensitive to the states mediating the Mn-Mn interaction [Kimel, PRL 2005]. The measurements are performed from the infrared to visible range (100 -- 2600 meV) on high quality samples with different Mn concentration (1.5 -- 14 %) with Curie temperatures up to 190 K. The results are compared with the predictions of k.p theory with antiferromagnetic p-d exchange. We acknowledge the financial support provided by NSF-DMR1006078 and Faculty of Mathematics and Physics, Charles University in Prague.

  10. Infrared and visible image fusion scheme based on NSCT and low-level visual features

    NASA Astrophysics Data System (ADS)

    Li, Huafeng; Qiu, Hongmei; Yu, Zhengtao; Zhang, Yafei

    2016-05-01

    Multi-scale transform (MST) is an efficient tool for image fusion. Recently, many fusion methods have been developed based on different MSTs, and they have shown potential application in many fields. In this paper, we propose an effective infrared and visible image fusion scheme in nonsubsampled contourlet transform (NSCT) domain, in which the NSCT is firstly employed to decompose each of the source images into a series of high frequency subbands and one low frequency subband. To improve the fusion performance we designed two new activity measures for fusion of the lowpass subbands and the highpass subbands. These measures are developed based on the fact that the human visual system (HVS) percept the image quality mainly according to its some low-level features. Then, the selection principles of different subbands are presented based on the corresponding activity measures. Finally, the merged subbands are constructed according to the selection principles, and the final fused image is produced by applying the inverse NSCT on these merged subbands. Experimental results demonstrate the effectiveness and superiority of the proposed method over the state-of-the-art fusion methods in terms of both visual effect and objective evaluation results.

  11. CHARACTERISTIC SIZE OF FLARE KERNELS IN THE VISIBLE AND NEAR-INFRARED CONTINUA

    SciTech Connect

    Xu, Yan; Jing, Ju; Wang, Haimin; Cao, Wenda

    2012-05-01

    In this Letter, we present a new approach to estimate the formation height of visible and near-infrared emission of an X10 flare. The sizes of flare emission cores in three wavelengths are accurately measured during the peak of the flare. The source size is the largest in the G band at 4308 A and shrinks toward longer wavelengths, namely the green continuum at 5200 A and NIR at 15600 A, where the emission is believed to originate from the deeper atmosphere. This size-wavelength variation is likely explained by the direct heating model as electrons need to move along converging field lines from the corona to the photosphere. Therefore, one can observe the smallest source, which in our case is 0.''65 {+-} 0.''02 in the bottom layer (represented by NIR), and observe relatively larger kernels in upper layers of 1.''03 {+-} 0.''14 and 1.''96 {+-} 0.''27, using the green continuum and G band, respectively. We then compare the source sizes with a simple magnetic geometry to derive the formation height of the white-light sources and magnetic pressure in different layers inside the flare loop.

  12. Rapid discrimination of enhanced quality pork by visible and near infrared spectroscopy.

    PubMed

    Prieto, N; Juárez, M; Larsen, I L; López-Campos, Ó; Zijlstra, R T; Aalhus, J L

    2015-12-01

    This study tested the ability of visible and near infrared spectroscopy (Vis-NIRS) to discriminate enhanced quality pork. Vis-NIR spectra were collected on intact chops from 148 pork carcasses using a portable LabSpec®4 spectrometer (350-2500 nm). Partial least squares discriminant analyses based on Vis-NIR spectra correctly classified 94, 95 and 100% of the 2d, and 95, 98 and 100% of the 14 d aged pork samples within Lacombe, Duroc and Iberian pig breeds, respectively. Moreover, Vis-NIRS correctly classified 97 and 99% of the moisture enhanced (ME) and Non-ME pork samples aged for 2d, and 94 and 95% of those aged for 14 d, as well as 94 and 97% of the 2 and 14 d aged pork samples, respectively. Conversely, Vis-NIRS technology could not differentiate pork samples based on pre-slaughter diet or post-slaughter carcass chilling process. Vis-NIRS can segregate enhanced quality pork according to production factors and post-mortem strategies such as pig breed, moisture enhancing and ageing period. PMID:26188360

  13. Highly sensitive visible to infrared MoTe2 photodetectors enhanced by the photogating effect.

    PubMed

    Huang, Hai; Wang, Jianlu; Hu, Weida; Liao, Lei; Wang, Peng; Wang, Xudong; Gong, Fan; Chen, Yan; Wu, Guangjian; Luo, Wenjin; Shen, Hong; Lin, Tie; Sun, Jinglan; Meng, Xiangjian; Chen, Xiaoshuang; Chu, Junhao

    2016-11-01

    Two-dimensional materials are promising candidates for electronic and optoelectronic applications. MoTe2 has an appropriate bandgap for both visible and infrared light photodetection. Here we fabricate a high-performance photodetector based on few-layer MoTe2. Raman spectral properties have been studied for different thicknesses of MoTe2. The photodetector based on few-layer MoTe2 exhibits broad spectral range photodetection (0.6-1.55 μm) and a stable and fast photoresponse. The detectivity is calculated to be 3.1 × 10(9) cm Hz(1/2) W(-1) for 637 nm light and 1.3 × 10(9) cm Hz(1/2) W(-1) for 1060 nm light at a backgate voltage of 10 V. The mechanisms of photocurrent generation have been analyzed in detail, and it is considered that a photogating effect plays an important role in photodetection. The appreciable performance and detection over a broad spectral range make it a promising material for high-performance photodetectors.

  14. Discrimination between Sedimentary Rocks from Close-Range Visible and Very-Near-Infrared Images

    PubMed Central

    Del Pozo, Susana; Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo; Kees Blom, Jan; González-Aguilera, Diego

    2015-01-01

    Variation in the mineral composition of rocks results in a change of their spectral response capable of being studied by imaging spectroscopy. This paper proposes the use of a low-cost handy sensor, a calibrated visible-very near infrared (VIS-VNIR) multispectral camera for the recognition of different geological formations. The spectral data was recorded by a Tetracam Mini-MCA-6 camera mounted on a field-based platform covering six bands in the spectral range of 0.530–0.801 µm. Twelve sedimentary formations were selected in the Rhône-Alpes region (France) to analyse the discrimination potential of this camera for rock types and close-range mapping applications. After proper corrections and data processing, a supervised classification of the multispectral data was performed trying to distinguish four classes: limestones, marlstones, vegetation and shadows. After a maximum-likelihood classification, results confirmed that this camera can be efficiently exploited to map limestone-marlstone alternations in geological formations with this mineral composition. PMID:26147309

  15. Highly sensitive visible to infrared MoTe2 photodetectors enhanced by the photogating effect

    NASA Astrophysics Data System (ADS)

    Huang, Hai; Wang, Jianlu; Hu, Weida; Liao, Lei; Wang, Peng; Wang, Xudong; Gong, Fan; Chen, Yan; Wu, Guangjian; Luo, Wenjin; Shen, Hong; Lin, Tie; Sun, Jinglan; Meng, Xiangjian; Chen, Xiaoshuang; Chu, Junhao

    2016-11-01

    Two-dimensional materials are promising candidates for electronic and optoelectronic applications. MoTe2 has an appropriate bandgap for both visible and infrared light photodetection. Here we fabricate a high-performance photodetector based on few-layer MoTe2. Raman spectral properties have been studied for different thicknesses of MoTe2. The photodetector based on few-layer MoTe2 exhibits broad spectral range photodetection (0.6–1.55 μm) and a stable and fast photoresponse. The detectivity is calculated to be 3.1 × 109 cm Hz1/2 W‑1 for 637 nm light and 1.3 × 109 cm Hz1/2 W‑1 for 1060 nm light at a backgate voltage of 10 V. The mechanisms of photocurrent generation have been analyzed in detail, and it is considered that a photogating effect plays an important role in photodetection. The appreciable performance and detection over a broad spectral range make it a promising material for high-performance photodetectors.

  16. A cryogenic dichroic mirror for separating visible light from wideband infrared

    NASA Astrophysics Data System (ADS)

    Enya, K.; Fujishiro, N.; Haze, K.; Kotani, T.; Kaneda, H.; Oyabu, S.; Ishihara, D.; Oseki, S.

    2014-08-01

    We present the design, fabrication and test results for a dichroic mirror, which was primarily developed for the SPICA Coronagraph Instrument (SCI), but is potentially useful for various types of astronomical instrument. The dichroic mirror is designed to reflect near- and mid-infrared but to transmit visible light. Two designs, one with 3 layers and one with 5 layers on BK7 glass substrates, are presented. The 3-layer design, consisting of Ag and ZnS, is simpler, and the 5-layer design, consisting of Ag and TiO2 is expected to have better performance. Tape tests, evaluation of the surface figure, and measurements of the reflectivity and transmittance were carried out at ambient temperature in air. The reflectivity obtained from measurements made on mirrors with 5 layers were < 80 % for wavelengths, λ, from 1.2 to 22 μm and < 90 % for λ from 1.8 to 20 μm. The transmittance obtained from measurements made on mirrors with 5 layers were < 70 % for λ between 0.4 and 0.8 μm. Optical ghosting is estimated to be smaller than 10-4 at λ < 1.5 μm. A protective coating for preventing corrosion was applied and its influence on the reflectivity and transmittance evaluated. A study examining the trade-offs imposed by various configurations for obtaining a telescope pointing correction signal was also undertaken.

  17. Discrimination between Sedimentary Rocks from Close-Range Visible and Very-Near-Infrared Images.

    PubMed

    Del Pozo, Susana; Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo; Kees Blom, Jan; González-Aguilera, Diego

    2015-01-01

    Variation in the mineral composition of rocks results in a change of their spectral response capable of being studied by imaging spectroscopy. This paper proposes the use of a low-cost handy sensor, a calibrated visible-very near infrared (VIS-VNIR) multispectral camera for the recognition of different geological formations. The spectral data was recorded by a Tetracam Mini-MCA-6 camera mounted on a field-based platform covering six bands in the spectral range of 0.530-0.801 µm. Twelve sedimentary formations were selected in the Rhône-Alpes region (France) to analyse the discrimination potential of this camera for rock types and close-range mapping applications. After proper corrections and data processing, a supervised classification of the multispectral data was performed trying to distinguish four classes: limestones, marlstones, vegetation and shadows. After a maximum-likelihood classification, results confirmed that this camera can be efficiently exploited to map limestone-marlstone alternations in geological formations with this mineral composition. PMID:26147309

  18. Radiometric measurement comparison using the Ocean Color Temperature Scanner (OCTS) visible and near infrared integrating sphere

    SciTech Connect

    Johnson, B.C.; Sakuma, F.; Butler, J.J.; Biggar, S.F.; Cooper, J.W.; Ishida, J.; Suzuki, K.

    1997-11-01

    As part of the pre-flight calibration and validation activities for the Ocean Color and Temperature Scanner (OCTS) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) ocean color satellite instruments, a radiometric measurement comparison was held in February 1995 at the NEC Corporation in Yokohama, Japan. Researchers from the National Institute of Standards and Technology (NIST), the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC), the University of Arizona Optical Sciences Center (UA), and the National Research Laboratory of Metrology (NRLM) in Tsukuba, Japan used their portable radiometers to measure the spectral radiance of the OCTS visible and near-infrared integrating sphere at four radiance levels. These four levels corresponded to the configuration of the OCTS integrating sphere when the calibration coefficients for five of the eight spectral channels, or bands, of the OCTS instrument were determined. The measurements of the four radiometers differed by {minus}2.7% to 3.9% when compared to the NEC calibration of the sphere and the overall agreement was within the combined measurement uncertainties. A comparison of the measurements from the participating radiometers also resulted in agreement within the combined measurement uncertainties. These results are encouraging and demonstrate the utility of comparisons using laboratory calibration integrating sphere sources. Other comparisons will focus on instruments that are scheduled for spacecraft in the NASA study of climate change, the Earth Observing System (EOS).

  19. Detection of canine skin and subcutaneous tumors by visible and near-infrared diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Cugmas, Blaž; Plavec, Tanja; Bregar, Maksimilijan; Naglič, Peter; Pernuš, Franjo; Likar, Boštjan; Bürmen, Miran

    2015-03-01

    Cancer is the main cause of canine morbidity and mortality. The existing evaluation of tumors requires an experienced veterinarian and usually includes invasive procedures (e.g., fine-needle aspiration) that can be unpleasant for the dog and the owner. We investigate visible and near-infrared diffuse reflectance spectroscopy (DRS) as a noninvasive optical technique for evaluation and detection of canine skin and subcutaneous tumors ex vivo and in vivo. The optical properties of tumors and skin were calculated in a spectrally constrained manner, using a lookup table-based inverse model. The obtained optical properties were analyzed and compared among different tumor groups. The calculated parameters of the absorption and reduced scattering coefficients were subsequently used for detection of malignant skin and subcutaneous tumors. The detection sensitivity and specificity of malignant tumors ex vivo were 90.0% and 73.5%, respectively, while corresponding detection sensitivity and specificity of malignant tumors in vivo were 88.4% and 54.6%, respectively. The obtained results show that the DRS is a promising noninvasive optical technique for detection and classification of malignant and benign canine skin and subcutaneous tumors. The method should be further investigated on tumors with common origin.

  20. Initial Reaction Dynamics of Proteorhodopsin Observed by Femtosecond Infrared and Visible Spectroscopy

    PubMed Central

    Neumann, Karsten; Verhoefen, Mirka-Kristin; Weber, Ingrid; Glaubitz, Clemens; Wachtveitl, Josef

    2008-01-01

    We present a comparative study using femtosecond pump/probe spectroscopy in the visible and infrared of the early photodynamics of solubilized proteorhodopsin (green absorbing variant) in D2O with deprotonated (pD 9.2) and protonated (pD 6.4) primary proton acceptor Asp-97. The vis-pump/vis-probe experiments show a kinetic isotope effect that is more pronounced for alkaline conditions, thus decreasing the previously reported pH-dependence of the primary reaction of proteorhodopsin in H2O. This points to a pH dependent H-bonding network in the binding pocket of proteorhodopsin, that directly influences the primary photo-induced dynamics. The vis-pump/IR-probe experiments were carried out in two different spectral regions and allowed to monitor the retinal C=C (1500 cm−1–1580 cm−1) and C=N stretching vibration as well as the amide I mode of the protein (1590 cm−1–1680 cm−1). Like the FTIR spectra of the K intermediate (PRK–PR difference spectra) in this spectral range, the kinetic parameters and also the quantum efficiency of photo-intermediate formation are found to be virtually independent of the pD value. PMID:18326639

  1. [Non-destructive brand identification of car wax using visible and near-infrared spectroscopy].

    PubMed

    Zhang, Yu; Tan, Li-Hong; He, Yong

    2014-02-01

    Visible and near-infrared (Vis-NIR) spectroscopy was applied to identify brands of car wax. A total of 104 samples were obtained for the analysis, in which 40 samples (calibration set) were used for model calibration, and the remaining 64 samples (prediction set) were used to validate the calibrated model independently. Linear discriminant analysis (LDA) and least square-support vector machine (LS-SVM) were respectively used to establish identification models for car wax with five brands based on their Vis-NIR spectra. Correct rates for prediction sample set were 84% and 97% for LDA and LS-SVM models, respectively. Spectral variable selection was further conducted by successive projections algorithm, (SPA), resulting in seven feature variables (351, 365, 401, 441, 605, 926, and 980 nm) selected from full range spectra that had 751 variables. The new LS-SVM model established using the feature variables selected by SPA also had the correct rate of 97%, showing that the selected variables had the most important information for brand identification, while other variables with no useful information were eliminated efficiently. The use of SPA and LS-SVM could not only obtain a high correct identification rate, but also simplify the model calibration and calculation. SPA-LS-SVM model could extract the useful information from the Vis-NIR spectra of car wax rapidly and accurately for the non-destructive brand identification of car wax.

  2. Two-scale image fusion of visible and infrared images using saliency detection

    NASA Astrophysics Data System (ADS)

    Bavirisetti, Durga Prasad; Dhuli, Ravindra

    2016-05-01

    Military, navigation and concealed weapon detection need different imaging modalities such as visible and infrared to monitor a targeted scene. These modalities provide complementary information. For better situation awareness, complementary information of these images has to be integrated into a single image. Image fusion is the process of integrating complementary source information into a composite image. In this paper, we propose a new image fusion method based on saliency detection and two-scale image decomposition. This method is beneficial because the visual saliency extraction process introduced in this paper can highlight the saliency information of source images very well. A new weight map construction process based on visual saliency is proposed. This process is able to integrate the visually significant information of source images into the fused image. In contrast to most of the multi-scale image fusion techniques, proposed technique uses only two-scale image decomposition. So it is fast and efficient. Our method is tested on several image pairs and is evaluated qualitatively by visual inspection and quantitatively using objective fusion metrics. Outcomes of the proposed method are compared with the state-of-art multi-scale fusion techniques. Results reveal that the proposed method performance is comparable or superior to the existing methods.

  3. Transmittance of MCF-7 breast tumor cell line through visible and near infrared spectrum

    NASA Astrophysics Data System (ADS)

    Tabakoǧlu, H. Ã.-zgür

    2016-03-01

    In this study, light transmittance of MCF-7 tumor cells from 450 nm to 1100 nm has been measured in their growing medium and evaluated. Transmittance differences have been tried to be put forward in cancer cell line on visible (VIS) and near infrared (NIR) spectrum as well as in between different numbers of cells in medium. An absorption-reflection spectrophotometer was used in the experiments. System has a tungsten light source, optical chopper, a monochromator, sample chamber, silicon detectors, lock-in amplifier and computer. System was controlled by software in order to adjust scan range, scan steps and grating configuration. Cells were grown in medium, and measurements were taken from cells while they were in 5 ml medium. According to our findings, there are significant differences between VIS and NIR regions for the same number of cells. There were found no statistical difference among different numbers of cells. Increasing number of cells has not affected the transmittance. Transmittance of medium is not significantly different from different concentration of cells.

  4. Origin of the infrared to visible upconversion mechanisms in Nd 3+-doped potassium lead chloride crystal

    NASA Astrophysics Data System (ADS)

    Mendioroz, A.; Balda, R.; Al-Saleh, M.; Fernández, J.

    2005-10-01

    The infrared to visible upconversion mechanisms of Nd3+ ions in potassium lead chloride crystal have been investigated at liquid nitrogen temperature (LNT). We have observed upconversion luminescence when pumping into both 4F3/2 and 4F5/2 bands and off-resonance, at 851 and 856 nm. The main bands appearing in the emission spectra are two blue bands located at 420 and 435 nm, corresponding to transitions 4D3/2 → 4I13/2 and 2P1/2 → 4I9/2 respectively, and green, orange and red emissions, located at 535, 595 and 668 nm, corresponding to 4G7/2-4G9/2 → 4I9/2, 4I11/2, 4I13/2 transitions, respectively. The results show that, upon excitation of either the 4F3/2 or 4F5/2 band at LNT, two- and three-body energy transfer upconversion process are responsible for the emissions coming from levels 4G7/2-4G9/2 (535, 595, and 668 nm) and 4D3/2 (420 nm), respectively. However, the experimental data indicate that the mechanisms leading to the luminescence coming from level 2P1/2 depend on the pumping wavelength and sample temperature.

  5. [Dynamic Detection of Fresh Jujube Based on ELM and Visible/Near Infrared Spectra].

    PubMed

    Yang, Yi; Zhang, Shu-juan; He, Yong

    2015-07-01

    Jujube was rich in nutrition and variety. In different varieties, there were very different from the market price to the qualities of internal and external. In order to realize the rapid and non-destructive detection of fresh jujubes' classification, Ban jujube, Jixin jujube and Xiang jujube were selected as research objects to collect their visible/near infrared spectral data dynamically. A combination of Moving Smoothing and Multiplicative Scatter Correction (MSC) was applied as the pretreatment method. After the pretreatment, the characteristic wavelengths extracted by Successive Projections Algorithm (SPA) were 980 nm, 1860, 1341, 1386, 2096, 1831, 1910, 1628, 441, 768 and 601 nm, respectively. And the importance reduced in accordance with the order. The 11 characteristic wavelengths were adopted as input variable to established Extreme Learning Machine (ELM) classification model, which was used for prediction. Comparing the ELM model's classification accuracy with other methods' classification accuracy such as Partial Least Squares Discriminant Analysis (PLS-DA) and Least Squares Support Vecor Machines (LS-SVM), the result indicated that: the R2 and the RMSEC of the SPA-ELM model was 0.97238 and 0.018724, respectively. The classification accuracy of the SPA-ELM model was 100% as good as the SPA-PLS-DA and SPA-LS-SVM. ELM was an effective classification method. This study provides a new theoretical basis for detection of fresh jujubes' classification. PMID:26717742

  6. Characterization of NPP Visible/Infrared Imager Radiometer Suite (VIIRS) Reflective Solar Bands Dual Gain Anomaly

    NASA Technical Reports Server (NTRS)

    Lee, Shihyan; McIntire, Jeff; Oudari, Hassan

    2012-01-01

    The Visible/Infrared Imager Radiometer Suite (VIIRS) contains six dual gain bands in the reflective solar spectrum. The dual gain bands are designed to switch gain mode at pre-defined thresholds to achieve high resolution at low radiances while maintaining the required dynamic range for science. During pre-launch testing, an anomaly in the electronic response before transitioning from high to low gain was discovered and characterized. On-orbit, the anomaly was confirmed using MODIS data collected during Simultaneous Nadir Overpasses (SNOs). The analysis of the Earth scene data shows that dual gain anomaly can be determined at the orbital basis. To characterize the dual gain anomaly, the anomaly region and electronic offsets were tracked per week during the first 8 month of VIIRS operation. The temporal analysis shows the anomaly region can drift 20 DN and is impacted by detectors DC Restore. The estimated anomaly flagging regions cover 2.5 % of the high gain dynamic range and are consistent with prelaunch and on-orbit LUT. The prelaunch results had a smaller anomaly range (30-50 DN) and are likely the results of more stable electronics from the shorter data collection time. Finally, this study suggests future calibration efforts to focus on the anomaly's impact on science products and possible correction method to reduce uncertainties.

  7. Proceedings of the 11th JPL Airborne Earth Science Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O.

    2002-01-01

    This publication contains the proceedings of the JPL Airborne Earth Science Workshop forum held to report science research and applications results with spectral images measured by the NASA Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). These papers were presented at the Jet Propulsion Laboratory from March 5-8, 2001. Electronic versions of these papers may be found at the A VIRIS Web http://popo.jpl.nasa.gov/pub/docs/workshops/aviris.proceedings.html

  8. Lunar Resources Using Moderate Spectral Resolution Visible and Near-infrared Spectroscopy: Al/si and Soil Maturity

    NASA Technical Reports Server (NTRS)

    Fischer, Erich M.; Pieters, Carle M.; Head, James W.

    1992-01-01

    Modern visible and near-infrared detectors are critically important for the accurate identification and relative abundance measurement of lunar minerals; however, even a very small number of well-placed visible and near-infrared bandpass channels provide a significant amount of general information about crucial lunar resources. The Galileo Solid State Imaging system (SSI) multispectral data are an important example of this. Al/Si and soil maturity will be discussed as examples of significant general lunar resource information that can be gleaned from moderate spectral resolution visible and near-infrared data with relative ease. Because quantitative-albedo data are necessary for these kinds of analyses, data such as those obtained by Galileo SSI are critical. SSI obtained synoptic digital multispectral image data for both the nearside and farside of the Moon during the first Galileo Earth-Moon encounter in December 1990. The data consist of images through seven filters with bandpasses ranging from 0.40 microns in the ultraviolet to 0.99 microns in the near-infrared. Although these data are of moderate spectral resolution, they still provide information for the following lunar resources: (1) titanium content of mature mare soils based upon the 0.40/0.56-micron (UV/VIS) ratio; (2) mafic mineral abundance based upon the 0.76/0.99-micron ratio; and (3) the maturity or exposure age of the soils based upon the 0.56-0.76-micron continuum and the 0.76/0.99-micron ratio. Within constraints, these moderate spectral resolution visible and near-infrared reflectance data can also provide elemental information such as Al/Si for mature highland soils.

  9. High Q micro-ring resonators fabricated from polycrystalline aluminum nitride films for near infrared and visible photonics.

    PubMed

    Pernice, Wolfram H P; Xiong, Chi; Tang, Hong X

    2012-05-21

    We demonstrate wideband integrated photonic circuits in sputter-deposited aluminum nitride (AlN) thin films. At both near-infrared and visible wavelengths, we achieve low propagation loss in integrated waveguides and realize high-quality optical resonators. In the telecoms C-band (1520-1580 nm), we obtain the highest optical Q factor of 440,000. Critical coupled devices show extinction ratio above 30 dB. For visible wavelengths (around 770 nm), intrinsic quality factors in excess of 30,000 is demonstrated. Our work illustrates the potential of AlN as a low loss material for wideband optical applications.

  10. Airborne measurements in the longwave infrared using an imaging hyperspectral sensor

    NASA Astrophysics Data System (ADS)

    Allard, Jean-Pierre; Chamberland, Martin; Farley, Vincent; Marcotte, Frédérick; Rolland, Matthias; Vallières, Alexandre; Villemaire, André

    2008-07-01

    Emerging applications in Defense and Security require sensors with state-of-the-art sensitivity and capabilities. Among these sensors, the imaging spectrometer is an instrument yielding a large amount of rich information about the measured scene. Standoff detection, identification and quantification of chemicals in the gaseous state is one important application. Analysis of the surface emissivity as a means to classify ground properties and usage is another one. Imaging spectrometers have unmatched capabilities to meet the requirements of these applications. Telops has developed the FIRST, a LWIR hyperspectral imager. The FIRST is based on the Fourier Transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. The FIRST, a man portable sensor, provides datacubes of up to 320×256 pixels at 0.35mrad spatial resolution over the 8-12 μm spectral range at spectral resolutions of up to 0.25cm-1. The FIRST has been used in several field campaigns, including the demonstration of standoff chemical agent detection [http://dx.doi.org/10.1117/12.788027.1]. More recently, an airborne system integrating the FIRST has been developed to provide airborne hyperspectral measurement capabilities. The airborne system and its capabilities are presented in this paper. The FIRST sensor modularity enables operation in various configurations such as tripod-mounted and airborne. In the airborne configuration, the FIRST can be operated in push-broom mode, or in staring mode with image motion compensation. This paper focuses on the airborne operation of the FIRST sensor.

  11. Broadly tunable Cr 4+-doped solid-state lasers in the near infrared and visible

    NASA Astrophysics Data System (ADS)

    Sennaroglu, Alphan

    2002-11-01

    This manuscript provides a comprehensive review of the characteristics of Cr 4+-doped solid-state lasers which produce broadly tunable coherent radiation in the near-infrared region of the electromagnetic spectrum between 1.13 and 1.63 μm. Cr 4+-doped gain media have several favorable characteristics including broad absorption bands that overlap with the operating wavelengths of several commercial pump lasers, a 4-level energy structure that allows continuous-wave as well as pulsed operation with low threshold pump powers, and the presence of broad amplification bands for the generation of ultrashort optical pulses. In addition, non-linear frequency conversion schemes can be readily employed to construct broadly tunable coherent visible sources based on Cr 4+-doped gain media. These favorable features make Cr 4+-doped lasers potentially important in many applications in optical communications, eye-safe imaging, medicine, and spectroscopy. After a description of the basic physical mechanisms that lead to broad emission in tunable solid-state lasers in general and Cr 4+-doped gain media in particular, the manuscript provides a detailed description of the operational characteristics of Cr 4+-doped lasers, including rate-equation analysis of power performance, role of thermal effects, and different mode-locking techniques for the generation of ultrashort optical pulses. Later sections focus on the work performed in the development and characterization of specific examples of Cr 4+-doped lasers. Particular attention is given to Cr 4+:forsterite and Cr 4+:YAG laser systems due to their superior power performance. Gain-switched, continuous-wave, and mode-locked operations of these lasers are described with a particular emphasis on recent developments. Studies carried out with other Cr 4+-doped lasers such as Cr 4+:Y 2SiO 5, Cr 4+-doped oxyapatite, Cr 4+-doped garnets, and Cr 4+:Ca 2GeO 4 are also described. Finally, use of non-linear conversion schemes in the generation

  12. An analysis of water in galactic infrared sources using the NASA Lear Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Smith, L. L.; Hilgeman, T.

    1979-01-01

    The Michelson interferometer system on the NASA Lear Jet Airborne Observatory is described as well as the data reduction procedures. The objects observed (standard stars, M stars, a nebula, planets, and the moon) are discussed and the observing parameters are listed for each flight date. The spectra obtained from these data flights are presented, grouped by class of object.

  13. Mineralogic Mapping of the Numisia region on Vesta from the Visible Infrared mapping spectrometer onboard NASA/Dawn

    NASA Astrophysics Data System (ADS)

    Frigeri, A.; De Sanctis, M. C.; Ammannito, E.; Tosi, F.; Capaccioni, F.; Capria, M. T.; Zambon, F.; Palomba, E.; Longobardo, A.; Fonte, S.; Giardino, M.; Buczkowski, D. L.; Jaumann, R.; Raymond, C.; Russell, C.

    2014-04-01

    The NASA/Dawn mission [1] has collected data from the asteroid Vesta for a year, from summer 2011 to summer 2012. During the phase of the mission around Vesta, The Visible and Infrared Mapping Spectrometer (VIR) acquired infrared and visible spectra from 0.2 to 5 microns, sampled in 864 channels with a spatial resolution reaching about 150 m/pixel. The good coverage and the resolution of the data from VIR allows to explore the mineral diversity of the surface of the asteroid at a good detail. Following the quadrangle scheme used for the imagery Atlas of Vesta [2], the VIR and Dawn team is studying the mineralogy of the quadrangles within the same geospatial framework where geomorphologic and geologic mapping activities had led to important results. In this work we analyze the mineralogic composition of this quadrangle using the data from VIR, integrated with dataset acquired from other experiments onboard the Dawn mission to Vesta.

  14. Temperature and salinity correction coefficients for light absorption by water in the visible to infrared spectral region.

    PubMed

    Röttgers, Rüdiger; McKee, David; Utschig, Christian

    2014-10-20

    The light absorption coefficient of water is dependent on temperature and concentration of ions, i.e. the salinity in seawater. Accurate knowledge of the water absorption coefficient, a, and/or its temperature and salinity correction coefficients, Ψ(T) and Ψ(S), respectively, is essential for a wide range of optical applications. Values are available from published data only at specific narrow wavelength ranges or at single wavelengths in the visible and infrared regions. Ψ(T) and Ψ(S) were therefore spectrophotometrically measured throughout the visible, near, and short wavelength infrared spectral region (400 to ~2700 nm). Additionally, they were derived from more precise measurements with a point-source integrating-cavity absorption meter (PSICAM) for 400 to 700 nm. When combined with earlier measurements from the literature in the range of 2600 - 14000 nm (wavenumber: 3800 - 700 cm(-1)), the coefficients are provided for 400 to 14000 nm (wavenumber: 25000 to 700 cm(-1)).

  15. Antimicrobial photodynamic therapy using visible light plus water-filtered infrared-A (wIRA).

    PubMed

    Al-Ahmad, A; Tennert, C; Karygianni, L; Wrbas, K T; Hellwig, E; Altenburger, M J

    2013-03-01

    The aim of this study was to investigate the effectiveness of antimicrobial photodynamic therapy (APDT) using visible light together with water-filtered infrared-A (VIS+wIRA) to eradicate single species of planktonic bacteria and micro-organisms during initial oral bacterial colonization in situ. A broadband VIS+wIRA radiator with a water-filtered spectrum in the range 580-1400 nm was used for irradiation. Toluidine blue (TB) was utilized as a photosensitizer at concentrations of 5, 10, 25 and 50 µg ml(-1). The unweighted (absolute) irradiance was 200 mW cm(-2) and it was applied for 1 min. Planktonic cultures of Streptococcus mutans and Enterococcus faecalis were treated with APDT. Salivary bacteria harvested by centrifugation of native human saliva were also tested. In addition, initial bacterial colonization of bovine enamel slabs carried in the mouths of six healthy volunteers was treated in the same way. Up to 2 log(10) of S. mutans and E. faecalis were killed by APDT. Salivary bacteria were eliminated to a higher extent of 3.7-5 log(10). All TB concentrations tested proved to be highly effective. The killing rate of bacteria in the initial oral bacterial colonization was significant (P=0.004) at all tested TB concentrations, despite the interindividual variations found among study participants. This study has shown that APDT in combination with TB and VIS+wIRA is a promising method for killing bacteria during initial oral colonization. Taking the healing effects of wIRA on human tissue into consideration, this technique could be helpful in the treatment of peri-implantitis and periodontitis.

  16. Local changes in arterial oxygen saturation induced by visible and near-infrared light radiation.

    PubMed

    Yesman, S S; Mamilov, S O; Veligotsky, D V; Gisbrecht, A I

    2016-01-01

    In this study, we investigate the efficiency of laser radiation on oxyhemoglobin (HbO2) rate in blood vessels and its wavelength dependence. The results of in vivo experimental measurements of the laser-induced photodissociation of HbO2 in cutaneous blood vessels in the visible and near-infrared (IR) spectral range are presented. Arterial oxygen saturation (SpO2) was measured by a method of fingertip pulse oximetry, which is based on the measurement of the modulated pulse wave of the blood. The light irradiating the finger was provided by corresponding light-emitting diodes (LED) at 15 wavelengths in the 400-940 nm spectrum range. Statistical results with a value of p < 0.05 were viewed as being significant for all volunteers. The results show that there is a decrease in SpO2 in the blood under the influence of the transcutaneous laser irradiation. Three maxima in the spectral range (530, 600, and 850 nm) are revealed, wherein decrease in the relative concentration of SpO2 reaches 5 % ± 0.5 %. Near-IR radiation plays a dominant role in absorption of laser radiation by oxyhemoglobin in deeper layers of tissue blood vessels. The obtained data correlate with the processes of light propagation in biological tissue. The observed reduction in SpO2 indicates the process of photodissociation of HbO2 in vivo and may result in local increase in O2 in the tissue. Such laser-induced enrichment of tissue oxygenation can be used in phototherapy of pathologies, where the elimination of local tissue hypoxia is critical. PMID:26637304

  17. Visible/near-infrared spectrogoniometric observations and modeling of dust-coated rocks

    USGS Publications Warehouse

    Johnson, J. R.; Grundy, W.M.; Shepard, M.K.

    2004-01-01

    Interpretations of visible/near-infrared reflectance spectra of Mars are often complicated by the effects of dust coatings that obscure the underlying materials of interest. The ability to separate the spectral reflectance signatures of coatings and substrates requires an understanding of how their individual and combined reflectance properties vary with phase angle. Toward this end, laboratory multispectral observations of rocks coated with different amounts of Mars analog dust were acquired under variable illumination and viewing geometries using the Bloomsburg University Goniometer (BUG). These bidirectional reflectance distribution function (BRDF) data were fit with a two-layer radiative transfer model, which replicated BUG observations of dust-coated basaltic andesite substrates relatively well. Derived single scattering albedo and phase function parameters for the dust were useful in testing the model's ability to derive the spectrum of a "blind" substrate (unknown to the modeler) coated with dust. Subsequent tests were run using subsets of the BUG data restricted by goniometric or coating thickness coverage. Using the entire data set provided the best constraints on model parameters, although some reductions in goniometric coverage could be tolerated without substantial degradation. Predictably, the most thinly coated samples provided the best information on the substrate, whereas the thickest coatings best replicated the dust. Dust zenith optical thickness values ???0.6-0.8 best constrain the substrate and coating simultaneously, particularly for large ranges of incidence or emission angles. The lack of sufficient angles can be offset by having a greater number and range of coatings thicknesses. Given few angles and thicknesses, few constraints can be placed concurrently on the spectral properties of the coating and substrate. ?? 2004 Elsevier Inc. All rights reserved.

  18. Visible and near infrared resonance plasmonic enhanced nanosecond laser optoporation of cancer cells

    PubMed Central

    St-Louis Lalonde, Bastien; Boulais, Étienne; Lebrun, Jean-Jacques; Meunier, Michel

    2013-01-01

    In this paper, we report a light driven, non-invasive cell membrane perforation technique based on the localized field amplification by a nanosecond pulsed laser near gold nanoparticles (AuNPs). The optoporation phenomena is investigated with pulses generated by a Nd:YAG laser for two wavelengths that are either in the visible (532 nm) or near infrared (NIR) (1064 nm). Here, the main objective is to compare on and off localized surface plasmonic resonance (LSPR) to introduce foreign material through the cell membrane using nanosecond laser pulses. The membrane permeability of human melanoma cells (MW278) has been successfully increased as shown by the intake of a fluorescent dye upon irradiation. The viability of this laser driven perforation method is evaluated by propidium iodide exclusion as well as MTT assay. Our results show that up to 25% of the cells are perforated with 532 nm pulses at 50 mJ/cm2 and around 30% of the cells are perforated with 1064 nm pulses at 1 J/cm2. With 532 nm pulses, the viability 2 h after treatment is 64% but it increases to 88% 72 h later. On the other hand, the irradiation with 1064 nm pulses leads to an improved 2 h viability of 81% and reaches 98% after 72 h. Scanning electron microscopy images show that the 5 pulses delivered during treatment induce changes in the AuNPs size distribution when irradiated by a 532 nm beam, while this distribution is barely affected when 1064 nm is used. PMID:23577284

  19. Local changes in arterial oxygen saturation induced by visible and near-infrared light radiation.

    PubMed

    Yesman, S S; Mamilov, S O; Veligotsky, D V; Gisbrecht, A I

    2016-01-01

    In this study, we investigate the efficiency of laser radiation on oxyhemoglobin (HbO2) rate in blood vessels and its wavelength dependence. The results of in vivo experimental measurements of the laser-induced photodissociation of HbO2 in cutaneous blood vessels in the visible and near-infrared (IR) spectral range are presented. Arterial oxygen saturation (SpO2) was measured by a method of fingertip pulse oximetry, which is based on the measurement of the modulated pulse wave of the blood. The light irradiating the finger was provided by corresponding light-emitting diodes (LED) at 15 wavelengths in the 400-940 nm spectrum range. Statistical results with a value of p < 0.05 were viewed as being significant for all volunteers. The results show that there is a decrease in SpO2 in the blood under the influence of the transcutaneous laser irradiation. Three maxima in the spectral range (530, 600, and 850 nm) are revealed, wherein decrease in the relative concentration of SpO2 reaches 5 % ± 0.5 %. Near-IR radiation plays a dominant role in absorption of laser radiation by oxyhemoglobin in deeper layers of tissue blood vessels. The obtained data correlate with the processes of light propagation in biological tissue. The observed reduction in SpO2 indicates the process of photodissociation of HbO2 in vivo and may result in local increase in O2 in the tissue. Such laser-induced enrichment of tissue oxygenation can be used in phototherapy of pathologies, where the elimination of local tissue hypoxia is critical.

  20. An improved version of the Visible and Near Infrared (VNIR) spectrometer of EChO

    NASA Astrophysics Data System (ADS)

    Bellucci, G.; Adriani, A.; Gambicorti, L.; Focardi, M.; Oliva, E.; Farina, M.; Di Giorgio, A. M.; Pace, E.; Piccioni, G.; Filacchione, G.; Pancrazzi, M.; Tozzi, A.; Micela, G.

    2014-08-01

    The Visible and Near Infrared (VNIR) is one of the modules of EChO, the Exoplanets Characterization Observatory proposed to ESA for an M-class mission. EChO is aimed to observe planets while transiting by their suns. Then the instrument has be designed to assure a high efficiency over the whole spectral range. In fact, it has to be able to observe stars with an apparent magnitude Mv= 9÷12 and able to see contrasts of 10-4÷10-5 in order to reveal the characteristics of the atmospheres of the exoplanets under investigation. VNIR was originally designed for covering the spectral range from 0.4 to 1.0 μm [1] but now the design has been reviewed and its spectral range has been extended up to 2.5 μm. It is a spectrometer in a cross-dispersed configuration that, then, uses the combination of a diffraction grating and a prism to spread the light in different wavelengths and in a useful number of orders of diffraction. Its resolving power is about 330 over the entire spectral range and its field of view is approximately 2 arcsec. The spectrometer is functionally split into two channels respectively working in the 0.4-1.0 μm and 1.0-2.5 μm spectral ranges. Such a solution is imposed by the fact the light at low wavelengths has to be shared with the EChO Fine Guiding System (FGS) devoted to the pointing of the stars under observation. The instrument works at 45K and its weight is 6 kg.

  1. Visible and near infrared sensitive photorefractive polymers for holographic display applications

    NASA Astrophysics Data System (ADS)

    Eralp, Muhsin

    This work presents recent advances in photorefractive polymer composites towards improved efficiency, speed, persistence of holograms and sensitivity at both visible and near infrared wavelengths. Besides the pure performance characteristics, a thin-device approach is presented to reduce operating voltage of these devices to practical levels and these materials are analyzed in both reflection and transmission geometries. The thin device operating at 1.3kV holds erasable, Bragg holograms with 80% efficiency in addition to its video-rate response time. The transition of hologram state from 'thick' to 'thin' is analyzed in detail. On the near IR portion of spectrum, new photorefractive polymer composites have been developed that enable high performance operation at 845nm and 975nm. Utilizing our novel photorefractive materials we demonstrate large diffraction efficiency in four-wave mixing experiments and video-rate response times. A major step towards achieving submillisecond response times is obtained through recording photorefractive gratings with individual nanosecond pulses at 532nm. At 4 mJ/cm2 illumination, a maximum diffraction efficiency of 56% has been obtained with a build-up time of only 300mus (t1). This fast response enables applications in optical processing requiring frame rates of 100Hz or more. Due to the short duration of the writing pulses, the recording is insensitive to vibrations. Combining molecules that have different frontier orbital energies in a copolymer system and utilizing thermal fixing approach has led to long grating lifetimes of more than several hours. Later, in this dissertation, two low-glass-transition photorefractive polymer composites are investigated in reflection geometry. 60% is diffraction efficiency is observed in 105mum thick devices of a PVK based composite. The reflection holograms are more sensitive to reading angle and slight birefringence due to the poling of chromophores has proven to cause a Bragg mismatch.

  2. The GIS data model of the Visible and Infrared mapping spectrometer (VIR) onboard NASA/Dawn

    NASA Astrophysics Data System (ADS)

    Frigeri, Alessandro; De Sanctis, Maria Cristina; Ammannito, Eleonora; Capaccioni, Fabrizio; VIR Team

    2016-10-01

    The spectrometer onboard Dawn mission to Vesta and Ceres (Russell et al., Earth Moon Planet (2007) 101:65–91) is a hyperspectral spectrometer with imaging capability which returns data useful for the determination of the mineral composition of surface materials in their geologic context. The VIR Spectrometer—covering the range from the near UV (0.25 μm) to the near IR (5.0 μm) and having moderate to high spectral resolution and imaging capabilities—is the appropriate instrument for the determination of Vesta's and Ceres' global and local properties (De Sanctis et al., SSR 2011). VIR combines two data channels in one compact instrument. The visible channel covers 0.25–1.05 μm and the infrared channel covers 1–5.0 μm. VIR is inherited from the VIRTIS mapping spectrometer (Coradini et al. in Planet. Space Sci. 46:1291–1304, 1998; Reininger et al. in Proc. SPIE 2819:66–77, 1996) on board the ESA Rosetta mission.Since the beginning of the scientific campaign, VIR calibrated data have been converted into a Geographic Information System (GIS) compatible format. Here we present the GIS data model we developed for VIR, which presents some unique peculiarities due to the specific NASA/Dawn mission design. The model has been developed starting from an object oriented modeling. This object oriented design gives the flexibility which is necessary to face, time to time, the unexpected aspects of remote sensing over planetary surfaces unobserved before with this kind of instruments.

  3. Analysis of visible and near infrared spectral reflectance for assessing metals in soil.

    PubMed

    Rathod, Paresh H; Müller, Ingo; Van der Meer, Freek D; de Smeth, Boudewijn

    2015-10-01

    Visible and near infrared reflectance (VNIR; 350-2500 nm) spectroscopy has greatly been used in soils, especially for studying variability in spectrally active soil components (e.g., organic carbon, clays, and Fe/Al oxides) based on their diagnostic spectral features. In recent years, this technique has also been applied to assess soil metallic ions. In this research, the feasibility of VNIR spectroscopy for determination of soil metals was investigated with two soil data sets: (i) artificially metal-spiked and (ii) in situ metal-contaminated soils. Results showed that reflectance spectra of neither metal-spiked soils with Cd, As, and Pb even at their higher concentrations of 20, 900, and 1200 mg kg(-1), respectively, nor in situ metal-contaminated soils (with concentrations of 30 mg Cd, 3019 mg As, and 5725 mg Pb kg(-1) soil) showed any recognized absorption peaks that correspond to soil metal concentrations. We observed variations in reflectance intensity for in situ metal-contaminated soils only, showing higher reflectance across the entire spectrum for strongly and lower for less metal-contaminated soils. A significant correlation was found between surface soil metals' concentrations and continuum removed spectra, while soil metals were also found significantly associated with soil organic matter and total Fe. A partial least square regression with cross-validation approach produced an acceptable prediction of metals (R (2) = 0.58-0.94) for both soil data sets, metal-spiked and in situ metal-contaminated soils. However, high values of root mean square error ruled out practical application of the achieved prediction models. PMID:27614958

  4. Detection of salmonid thermal refugia from airborne thermal infrared (TIR) imagery

    NASA Astrophysics Data System (ADS)

    Dugdale, S. J.; Bergeron, N.; Rousseau, M.

    2010-12-01

    During elevated summer temperatures, salmonid species seek out areas of cool, well-oxygenated river water to alleviate thermal stress. Collectively known as ‘thermal refugia’, these are of great significance to the ability of salmonids to survive increased water temperatures, and a better understanding of their spatial and temporal characteristics may aid mitigation strategies against the possible effects of climate change on rivers. However, thermal refugia are traditionally hard to detect, and their in-river abundance and spatial patterns are largely unknown. Although previous research has examined TIR imaging as a means to sense river temperatures, few have achieved a resolution amenable to the detection of small thermal anomalies typically used by salmonids, with the majority of literature focusing on the general application of thermal imaging to river temperature detection and analysis. From preliminary research, we note that riverine thermal anomalies (as viewed from TIR imagery) can comprise a number of different forms resulting from a diverse range of sources. Given that the structural, spatial and temporal dynamics of thermal refugia in gravel bed rivers are a presumably a function of the complex geomorphological processes within a catchment, the ability to discriminate multi-scale thermal refugia may aid our comprehension not only of the behaviour of salmonids during high temperature events, but also of the geomorphological phenomena that are fundamental in governing river temperature heterogeneity. Initial thermal infrared imagery acquired in August 2009 suggested that while it is possible to manually detect riverine temperature anomalies, the creation of a dedicated remote sensing platform capable of obtaining both TIR and RGB photography easily and with a resolution amenable to refugia detection would greatly aid our ability to discriminate true refugia from other thermal anomalies (false positives). To this end, we have developed a system able to

  5. Summaries of the Sixth Annual JPL Airborne Earth Science Workshop, March 4-8, 1996. Volume 2; AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Kim, Yunjin (Editor)

    1996-01-01

    This publication contains the summaries for the Sixth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on March 4-8, 1996. The main workshop is divided into two smaller workshops as follows: The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on March 4-6. The summaries for this workshop appear in Volume 1. The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on March 6-8. The summaries for this workshop appear in Volume 2.

  6. Remote sensing of soil moisture using airborne hyperspectral data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Institute for Technology Development (ITD) has developed an airborne hyperspectral sensor system that collects electromagnetic reflectance data of the terrain. The system consists of sensors for three different sections of the electromagnetic spectrum; the Ultra-Violet (UV), Visible/Near Infrare...

  7. NASA Stratospheric Observatory For Infrared Astronomy (SOFIA) Airborne Astronomy Ambassador Program Evaluation Results To Date

    NASA Astrophysics Data System (ADS)

    Harman, Pamela K.; Backman, Dana E.; Clark, Coral

    2015-08-01

    SOFIA is an airborne observatory, capable of making observations that are impossible for even the largest and highest ground-based telescopes, and inspires instrumention development.SOFIA is an 80% - 20% partnership of NASA and the German Aerospace Center (DLR), consisting of a modified Boeing 747SP aircraft carrying a diameter of 2.5 meters (100 inches) reflecting telescope. The SOFIA aircraft is based at NASA Armstrong Flight Research Center, Building 703, in Palmdale, California. The Science Program Office and Outreach Office is located at NASA Ames Research center. SOFIA is one of the programs in NASA's Science Mission Directorate, Astrophysics Division.SOFIA will be used to study many different kinds of astronomical objects and phenomena, including star birth and death, formation of new solar systems, identification of complex molecules in space, planets, comets and asteroids in our solar system, nebulae and dust in galaxies, and ecosystems of galaxies.Airborne Astronomy Ambassador Program:The SOFIA Education and Communications program exploits the unique attributes of airborne astronomy to contribute to national goals for the reform of science, technology, engineering, and math (STEM) education, and to the elevation of public scientific and technical literacy.SOFIA’s Airborne Astronomy Ambassadors (AAA) effort is a professional development program aspiring to improve teaching, inspire students, and inform the community. To date, 55 educators from 21 states; in three cohorts, Cycles 0, 1 and 2; have completed their astronomy professional development and their SOFIA science flight experience. Cycle 3 cohort of 28 educators will be completing their flight experience this fall. Evaluation has confirmed the program’s positive impact on the teacher participants, on their students, and in their communities. Teachers have incorporated content knowledge and specific components of their experience into their curricula, and have given hundreds of presentations and

  8. Simulating Visible/Infrared Imager Radiometer Suite Normalized Difference Vegetation Index Data Using Hyperion and MODIS

    NASA Technical Reports Server (NTRS)

    Ross, Kenton W.; Russell, Jeffrey; Ryan, Robert E.

    2006-01-01

    The success of MODIS (the Moderate Resolution Imaging Spectrometer) in creating unprecedented, timely, high-quality data for vegetation and other studies has created great anticipation for data from VIIRS (the Visible/Infrared Imager Radiometer Suite). VIIRS will be carried onboard the joint NASA/Department of Defense/National Oceanic and Atmospheric Administration NPP (NPOESS (National Polar-orbiting Operational Environmental Satellite System) Preparatory Project). Because the VIIRS instruments will have lower spatial resolution than the current MODIS instruments 400 m versus 250 m at nadir for the channels used to generate Normalized Difference Vegetation Index data, scientists need the answer to this question: how will the change in resolution affect vegetation studies? By using simulated VIIRS measurements, this question may be answered before the VIIRS instruments are deployed in space. Using simulated VIIRS products, the U.S. Department of Agriculture and other operational agencies can then modify their decision support systems appropriately in preparation for receipt of actual VIIRS data. VIIRS simulations and validations will be based on the ART (Application Research Toolbox), an integrated set of algorithms and models developed in MATLAB(Registerd TradeMark) that enables users to perform a suite of simulations and statistical trade studies on remote sensing systems. Specifically, the ART provides the capability to generate simulated multispectral image products, at various scales, from high spatial hyperspectral and/or multispectral image products. The ART uses acquired ( real ) or synthetic datasets, along with sensor specifications, to create simulated datasets. For existing multispectral sensor systems, the simulated data products are used for comparison, verification, and validation of the simulated system s actual products. VIIRS simulations will be performed using Hyperion and MODIS datasets. The hyperspectral and hyperspatial properties of Hyperion

  9. Detection of coastal and submarine discharge on the Florida Gulf Coast with an airborne thermal-infrared mapping system

    USGS Publications Warehouse

    Raabe, Ellen; Stonehouse, David; Ebersol, Kristin; Holland, Kathryn; Robbins, Lisa

    2011-01-01

    Along the Gulf Coast of Florida north of Tampa Bay lies a region characterized by an open marsh coast, low topographic gradient, water-bearing limestone, and scattered springs. The Floridan aquifer system is at or near land surface in this region, discharging water at a consistent 70-72°F. The thermal contrast between ambient water and aquifer discharge during winter months can be distinguished using airborne thermal-infrared imagery. An airborne thermal-infrared mapping system was used to collect imagery along 126 miles of the Gulf Coast from Jefferson to Levy County, FL, in March 2009. The imagery depicts a large number of discharge locations and associated warm-water plumes in ponds, creeks, rivers, and nearshore waters. A thermal contrast of 6°F or more was set as a conservative threshold for identifying sites, statistically significant at the 99% confidence interval. Almost 900 such coastal and submarine-discharge locations were detected, averaging seven to nine per mile along this section of coast. This represents approximately one hundred times the number of previously known discharge sites in the same area. Several known coastal springs in Taylor and Levy Counties were positively identified with the imagery and were used to estimate regional discharge equivalent to one 1st-order spring, discharging 100 cubic feet per second or more, for every two miles of coastline. The number of identified discharge sites is a conservative estimate and may represent two-thirds of existing features due to low groundwater levels at time of overflight. The role of aquifer discharge in coastal and estuarine health is indisputable; however, mapping and quantifying discharge in a complex karst environment can be an elusive goal. The results of this effort illustrate the effectiveness of the instrument and underscore the influence of coastal springs along this stretch of the Florida coast.

  10. Visible and Infrared Radiative Relationships as Measured by Satellite and Lidar

    NASA Technical Reports Server (NTRS)

    Wylie, Donald; Wolf, Walt; Eloranta, Edwin

    1996-01-01

    The impact of cirrus clouds on the heat balance of the Earth is dependent on their reflectivity of solar radiation and their absorptivity of terrestrial radiation. Any prediction of cloud cover changes that accompany climate change will have to know whether the visible/IR radiative characteristics of the clouds will also change. Few measurements of cirrus clouds have been made where both visible and IR data were collected simultaneously. To obtain the visible optical depths of cirrus clouds, the High Spectral Resolution Lidar (HSRL) and the Volume Imaging Lidar (VIL) were used. The VIL produced visible backscatter images of the clouds by scanning across the wind. Time advection was used to construct a horizontal image of visible backscatter from the VIL data. The HSRL was used to calibrate the VIL signal into backscatter cross sections of particulates.

  11. Calibration of the visible and near-infrared channels of the NOAA-9 AVHRR using high-altitude aircraft measurements from August 1985 and October 1986

    NASA Technical Reports Server (NTRS)

    Smith, Gilbert R.; Levin, Robert H.; Koyanagi, Robert S.; Wrigley, Robert C.

    1989-01-01

    Visible and near infrared wavelength sensors mounted on operational satellites now in use do not have onboard absolute calibration devices. One means of establishing an in-orbit calibration for a satellite sensor is to make simultaneous measurement of a bright, relatively uniform scene along the satellite view vector from a calibrated instrument on board a high altitude aircraft. Herein, aircraft data were recorded over White Sands, New Mexico at satellite overpass time. Comparison of the coincident aircraft and orbiting satellite data for the visible and near infrared wavelength channels of the NOAA-9 Advanced Very High Resolution Radiometer shows that the calibration of the visible channel was unchanged from prelaunch values, but that the near infrared channel has degraded 6 percent by Aug. 1985. By Oct. 1986 the visible channel had degraded 13 percent and the near infrared channel had degraded 19 percent.

  12. Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice

    NASA Astrophysics Data System (ADS)

    Barker, Beau J.; Berg, John M.; Kozimor, Stosh A.; Wozniak, Nicholas R.; Wilkerson, Marianne P.

    2016-03-01

    Visible and near-infrared illumination induces 5f-5f and ligand-to-metal charge-transfer (LMCT) transitions of the neptunyl tetrachloride anion in polycrystalline Cs2U(Np)O2Cl4, and results in near-infrared luminescence from the second electronically excited state to the ground state. This photoluminescence is used as a detection method to collect excitation spectra throughout the near-infrared and visible regions. The excitation spectra of LMCT transitions in excitation spectra were identified in previous work. Here the measurement and analysis is extended to include both LMCT and intra-5f transitions. The results manifest variation in structural properties of the neptunium-oxo bond among the low-lying electronic states. Vibronic intensity patterns and energy spacings are used to compare bond lengths and vibrational frequencies in the excited states, confirming significant characteristic differences between those excited by 5f-5f transitions from those due to LMCT transitions. Results are compared with recently published RASPT2/SO calculations of [NpO2Cl4]2-.

  13. CO photodissociation dynamics in cytochrome P450BM3 studied by subpicosecond visible and mid-infrared spectroscopy.

    PubMed

    Rupenyan, Alisa; Commandeur, Jan; Groot, Marie Louise

    2009-07-01

    Cytochrome P450BM3 is a bacterial enzyme with a heme cofactor that binds small diatomic ligands. Here we report the first study of carbon monoxide (CO) photodissociation and rebinding in ferrous P450BM3 on an ultrafast time scale. We monitored dissociation of carbon monoxide upon Soret band excitation using visible and infrared femtosecond spectroscopy between 100 fs and 4 ns. The dynamics of the ferric P450 was probed for reference in the visible spectral region. In the photodissociated ferrous P450-CO complex, the vibrational hot deligated ground state is populated in 0.2 ps and relaxes on a picosecond time scale. The onset of geminate recombination of CO with the heme is observed on a nanosecond time scale. In the mid-infrared spectral region, the bleached absorption due to the bound C=O stretch vibration is constant on the picosecond to 1 ns time scale, indicating that the photodissociation yield is 100% and that rebinding occurs after 1 ns. In the infrared absorption difference spectra, we additionally resolve two small bands of dissociated CO molecules at 2092 and 2114 cm(-1). This indicates that the escape of photolyzed CO to solvent and the geminate recombination are preceded by transient docking within the protein in a manner similar to that of globins. The bands partially decay with a time constant of 1 ps, possibly due to a relaxation of the protein around the CO docking site, allowing for greater orientational freedom of the CO molecules.

  14. Ground-based All-sky Mid-infrared and Visible Imagery for Purposes of Characterizing Cloud Properties

    SciTech Connect

    Klebe, Dimitri; Blatherwick, R. D.; Morris, Victor R.

    2014-02-24

    This paper describes the All Sky Infrared Visible Analyzer (ASIVA), a multi-purpose visible and infrared sky imaging and analysis instrument whose primary functionality is to provide radiometrically calibrated imagery in the mid-infrared (mid-IR) atmospheric window. This functionality enables the determination of diurnal hemispherical cloud fraction (HCF) and estimates of sky/cloud temperature from which one can derive estimates of cloud emissivity and cloud height. This paper describes the calibration methods and performance of the ASIVA instrument with particular emphasis on data products being developed for the meteorological community. Data presented here were collected during a field campaign conducted at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Climate Research Facility from May 21 to July 27, 2009. The purpose of this campaign was to determine the efficacy of IR technology in providing reliable nighttime HCF data. Significant progress has been made in the analysis of the campaign data over the past several years and the ASIVA has proven to be an excellent instrument for determining HCF as well as several other important cloud properties.

  15. Detecting and Segregating Black Tip-Damaged Wheat Kernels Using Visible and Near Infrared Spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detection of individual wheat kernels with black tip symptom (BTS) and black tip damage (BTD) was demonstrated using near infrared reflectance spectroscopy (NIRS) and silicon light-emitting-diode (LED) based instruments. The two instruments tested, a single kernel near-infrared spectroscopy instrume...

  16. Summaries of the 4th Annual JPL Airborne Geoscience Workshop. Volume 2: TIMS Workshop

    NASA Technical Reports Server (NTRS)

    Realmuto, Vincent J. (Editor)

    1993-01-01

    This is volume 2 of a three volume set of publications that contain the summaries for the Fourth Annual JPL Airborne Geoscience Workshop, held in Washington, D.C. on October 25-29, 1993. The main workshop is divided into three smaller workshops as follows: The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on October 25-26. The summaries for this workshop appear in Volume 1. The Thermal Infrared Multispectral Scanner (TIMS) workshop, on October 27. The summaries for this workshop appear in Volume 2. The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on October 28-29. The summaries for this workshop appear in Volume 3.

  17. Summaries of the Third Annual JPL Airborne Geoscience Workshop. Volume 1: AVIRIS Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O. (Editor)

    1992-01-01

    This publication contains the preliminary agenda and summaries for the Third Annual JPL Airborne Geoscience Workshop, held at the Jet Propulsion Laboratory, Pasadena, California, on 1-5 June 1992. This main workshop is divided into three smaller workshops as follows: (1) the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on June 1 and 2; (2) the Thermal Infrared Multispectral Scanner (TIMS) workshop, on June 3; and (3) the Airborne Synthetic Aperture Radar (AIRSAR) workshop, on June 4 and 5. The summaries are contained in Volumes 1, 2, and 3, respectively.

  18. Summaries of the 4th Annual JPL Airborne Geoscience Workshop. Volume 3: AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Vanzyl, Jakob (Editor)

    1993-01-01

    This publication contains the summaries for the Fourth Annual JPL Airborne Geoscience Workshop, held in Washington, D.C. on October 25-29, 1993. The main workshop is divided into three smaller workshops as follows: The Airborne Visible/Infrared Spectrometer (AVIRIS) workshop, on October 25-26, whose summaries appear in Volume 1; The Thermal Infrared Multispectral Scanner (TIMS) workshop, on October 27, whose summaries appear in Volume 2; and The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on October 28-29, whose summaries appear in this volume, Volume 3.

  19. Summaries of the Third Annual JPL Airborne Geoscience Workshop. Volume 2: TIMS Workshop

    NASA Technical Reports Server (NTRS)

    Realmuto, Vincent J. (Editor)

    1992-01-01

    This publication contains the preliminary agenda and summaries for the Third Annual JPL Airborne Geoscience Workshop, held at the Jet Propulsion Laboratory, Pasadena, California, on 1-5 June 1992. This main workshop is divided into three smaller workshops as follows: (1) the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on June 1 and 2; the summaries for this workshop appear in Volume 1; (2) the Thermal Infrared Multispectral Scanner (TIMS) workshop, on June 3; the summaries for this workshop appear in Volume 2; and (3) the Airborne Synthetic Aperture Radar (AIRSAR) workshop, on June 4 and 5; the summaries for this workshop appear in Volume 3.

  20. Summaries of the Fifth Annual JPL Airborne Earth Science Workshop. Volume 1: AVIRIS Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O. (Editor)

    1995-01-01

    This publication is the first of three containing summaries for the Fifth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on January 23-26, 1995. The main workshop is divided into three smaller workshops as follows: (1) The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on January 23-24. The summaries for this workshop appear in this volume; (2) The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on January 25-26. The summaries for this workshop appear in Volume 3; and (3) The Thermal Infrared Multispectral Scanner (TIMS) workshop, on January 26. The summaries for this workshop appear in Volume 2.

  1. Summaries of the Fifth Annual JPL Airborne Earth Science Workshop. Volume 2: TIMS Workshop

    NASA Technical Reports Server (NTRS)

    Realmuto, Vincent J. (Editor)

    1995-01-01

    This publication is the second volume of the summaries for the Fifth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on January 23-26, 1995. The main workshop is divided into three smaller workshops as follows: (1) The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop on January 23-24. The summaries for this workshop appear in Volume 1; (2) The Airborne Synthetic Aperture Radar (AIRSAR) workshop on January 25-26. The summaries for this workshop appear in volume 3; and (3) The Thermal Infrared Multispectral Scanner (TIMS) workshop on January 26. The summaries for this workshop appear in this volume.

  2. Summaries of the 4th Annual JPL Airborne Geoscience Workshop. Volume 1: AVIRIS Workshop

    NASA Technical Reports Server (NTRS)

    Green, Robert O. (Editor)

    1993-01-01

    This publication contains the summaries for the Fourth Annual JPL Airborne Geoscience Workshop, held in Washington, D. C. October 25-29, 1993 The main workshop is divided into three smaller workshops as follows: The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, October 25-26 (the summaries for this workshop appear in this volume, Volume 1); The Thermal Infrared Multispectral Scanner (TMIS) workshop, on October 27 (the summaries for this workshop appear in Volume 2); and The Airborne Synthetic Aperture Radar (AIRSAR) workshop, October 28-29 (the summaries for this workshop appear in Volume 3).

  3. Summaries of the Third Annual JPL Airborne Geoscience Workshop. Volume 3: AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Vanzyl, Jakob (Editor)

    1992-01-01

    This publication contains the preliminary agenda and summaries for the Third Annual JPL Airborne Geoscience Workshop, held at the Jet Propulsion Laboratory, Pasadena, California, on 1-5 June 1992. This main workshop is divided into three smaller workshops as follows: (1) the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on June 1 and 2; the summaries for this workshop appear in Volume 1; (2) the Thermal Infrared Multispectral Scanner (TIMS) workshop, on June 3; the summaries for this workshop appear in Volume 2; and (3) the Airborne Synthetic Aperture Radar (AIRSAR) workshop, on June 4 and 5; the summaries for this workshop appear in Volume 3.

  4. Summaries of the Fifth Annual JPL Airborne Earth Science Workshop. Volume 3: AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Vanzyl, Jakob (Editor)

    1995-01-01

    This publication is the third containing summaries for the Fifth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on January 23-26, 1995. The main workshop is divided into three smaller workshops as follows: (1) The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on January 23-24. The summaries for this workshop appear in Volume 1; (2) The Airborne synthetic Aperture Radar (AIRSAR) workshop, on January 25-26. The summaries for this workshop appear in this volume; and (3) The Thermal Infrared Multispectral Scanner (TIMS) workshop, on January 26. The summaries for this workshop appear in Volume 2.

  5. Wavelet-based decomposition of high resolution surface plasmon microscopy V(Z) curves at visible and near infrared wavelengths.

    PubMed

    Boyer-Provera, E; Rossi, A; Oriol, L; Dumontet, C; Plesa, A; Berguiga, L; Elezgaray, J; Arneodo, A; Argoul, F

    2013-03-25

    Surface plasmon resonance is conventionally conducted in the visible range and, during the past decades, it has proved its efficiency in probing molecular scale interactions. Here we elaborate on the first implementation of a high resolution surface plasmon microscope that operates at near infrared (IR) wavelength for the specific purpose of living matter imaging. We analyze the characteristic angular and spatial frequencies of plasmon resonance in visible and near IR lights and how these combined quantities contribute to the V(Z) response of a scanning surface plasmon microscope (SSPM). Using a space-frequency wavelet decomposition, we show that the V(Z) response of the SSPM for red (632.8 nm) and near IR (1550 nm) lights includes the frequential response of plasmon resonance together with additional parasitic frequencies induced by the objective pupil. Because the objective lens pupil profile is often unknown, this space-frequency decomposition turns out to be very useful to decipher the characteristic frequencies of the experimental V(Z) curves. Comparing the visible and near IR light responses of the SSPM, we show that our objective lens, primarily designed for visible light microscopy, is still operating very efficiently in near IR light. Actually, despite their loss in resolution, the SSPM images obtained with near IR light remain contrasted for a wider range of defocus values from negative to positive Z values. We illustrate our theoretical modeling with a preliminary experimental application to blood cell imaging.

  6. Wavelength-tunable visible to near-infrared photoluminescence of carbon dots: the role of quantum confinement and surface states

    NASA Astrophysics Data System (ADS)

    Ghamsari, Morteza Sasani; Bidzard, Ashkan Momeni; Han, Wooje; Park, Hyung-Ho

    2016-04-01

    Carbon quantum dots (C-QDs) with different size distributions and surface characteristics can exhibit good emission properties in the visible and near-infrared (NIR) regions, which can be applicable in optoelectronic devices as well as biomedical applications. Optical properties of colloidal C-QDs in distilled water at different concentrations produced using a method of alkali-assisted surfactant-free oxidation of cellulose acetate is presented. The structural and optical properties of colloidal C-QDs at different concentrations were investigated, with the aim of clarifying the main mechanisms of photoluminescence emissions. We observed a wide range of tunable visible to NIR emissions with good stability from the C-QD colloids at different applied excitation wavelengths. The colloids show dual emissions with maxima at ˜420 and 775 nm (blue and NIR emissions) when excited at the wavelength range near the energy gaps of the C-QDs. Moreover, by increasing the excitation wavelength, tunable visible emissions at the spectral range of 475 to 550 nm are observed. A detailed analysis of the results shows that the blue and NIR luminescence of colloidal C-QDs originate from the oxide-related surface effects whereas quantum confinement is the responsible mechanism for tunable visible emissions of the C-QD colloid.

  7. Wavelength-tunable visible to near-infrared photoluminescence of carbon dots: the role of quantum confinement and surface states

    NASA Astrophysics Data System (ADS)

    Ghamsari, Morteza Sasani; Bidzard, Ashkan Momeni; Han, Wooje; Park, Hyung-Ho

    2016-04-01

    Carbon quantum dots (C-QDs) with different size distributions and surface characteristics can exhibit good emission properties in the visible and near-infrared (NIR) regions, which can be applicable in optoelectronic devices as well as biomedical applications. Optical properties of colloidal C-QDs in distilled water at different concentrations produced using a method of alkali-assisted surfactant-free oxidation of cellulose acetate is presented. The structural and optical properties of colloidal C-QDs at different concentrations were investigated, with the aim of clarifying the main mechanisms of photoluminescence emissions. We observed a wide range of tunable visible to NIR emissions with good stability from the C-QD colloids at different applied excitation wavelengths. The colloids show dual emissions with maxima at ˜420 and 775 nm (blue and NIR emissions) when excited at the wavelength range near the energy gaps of the C-QDs. Moreover, by increasing the excitation wavelength, tunable visible emissions at the spectral range of 475 to 550 nm are observed. A detailed analysis of the results shows that the blue and NIR luminescence of colloidal C-QDs originate from the oxide-related surface effects whereas quantum confinement is the responsible mechanism for tunable visible emissions of the C-QD colloid.

  8. Revolutionary visible and infrared sensor detectors for the most advanced astronomical AO systems

    NASA Astrophysics Data System (ADS)

    Feautrier, Philippe; Gach, Jean-Luc; Guieu, Sylvain; Downing, Mark; Jorden, Paul; Rothman, Johan; de Borniol, Eric D.; Balard, Philippe; Stadler, Eric; Guillaume, Christian; Boutolleau, David; Coussement, Jérome; Kolb, Johann; Hubin, Norbert; Derelle, Sophie; Robert, Clélia; Tanchon, Julien; Trollier, Thierry; Ravex, Alain; Zins, Gérard; Kern, Pierre; Moulin, Thibaut; Rochat, Sylvain; Delpoulbé, Alain; Lebouqun, Jean-Baptiste

    2014-07-01

    We report in this paper decisive advance on the detector development for the astronomical applications that require very fast operation. Since the CCD220 and OCAM2 major success, new detector developments started in Europe either for visible and IR wavelengths. Funded by ESO and the FP7 Opticon European network, the NGSD CMOS device is fully dedicated to Natural and Laser Guide Star AO for the E-ELT with strong ESO involvement. The NGSD will be a 880x840 pixels CMOS detector with a readout noise of 3 e (goal 1e) at 700 Hz frame rate and providing digital outputs. A camera development, based on this CMOS device and also funded by the Opticon European network, is ongoing. Another major AO wavefront sensing detector development concerns IR detectors based on Avalanche Photodiode (e- APD) arrays within the RAPID project. Developed by the SOFRADIR and CEA/LETI manufacturers, the latter offers a 320x255 8 outputs 30 microns IR array, sensitive from 0.4 to 3 microns, with less than 2 e readout noise at 1600 fps. A rectangular window can also be programmed to speed up even more the frame rate when the full frame readout is not required. The high QE response, in the range of 70%, is almost flat over this wavelength range. Advanced packaging with miniature cryostat using pulse tube cryocoolers was developed in the frame of this programme in order to allow use on this detector in any type of environment. The characterization results of this device are presented here. Readout noise as low as 1.7 e at 1600 fps has been measured with a 3 microns wavelength cut-off chip and a multiplication gain of 14 obtained with a limited photodiode polarization of 8V. This device also exhibits excellent linearity, lower than 1%. The pulse tube cooling allows smart and easy cooling down to 55 K. Vibrations investigations using centroiding and FFT measurements were performed proving that the miniature pulse tube does not induce measurable vibrations to the optical bench, allowing use of this

  9. Visible-infrared remote-sensing model and applications for ocean waters. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Lee, Zhongping

    1994-01-01

    Remote sensing has become important in the ocean sciences, especially for research involving large spatial scales. To estimate the in-water constituents through remote sensing, whether carried out by satellite or airplane, the signal emitted from beneath the sea surface, the so called water-leaving radiance (L(w)), is of prime importance. The magnitude of L(w) depends on two terms: one is the intensity of the solar input, and the other is the reflectance of the in-water constituents. The ratio of the water-leaving radiance to the downwelling irradiance (E(d)) above the sear surface (remote-sensing reflectance, R(sub rs)) is independent of the intensity of the irradiance input, and is largely a function of the optical properties of the in-water constituents. In this work, a model is developed to interpret r(sub rs) for ocean water in the visible-infrared range. In addition to terms for the radiance scattered from molecules and particles, the model includes terms that describe contributions from bottom reflectance, fluorescence of gelbstoff or colored dissolved organic matter (CDOM), and water Raman scattering. By using this model, the measured R(sub rs) of waters from the West Florida Shelf to the Mississippi River plume, which covered a (concentration of chlorophyll a) range of 0.07 - 50 mg/cu m, were well interpreted. The average percentage difference (a.p.d.) between the measured and modeled R(sub rs) is 3.4%, and, for the shallow waters, the model-required water depth is within 10% of the chart depth. Simple mathematical simulations for the phytoplankton pigment absorption coefficient (a(sub theta)) are suggested for using the R(sub rs) model. The inverse problem of R(sub rs), which is to analytically derive the in-water constituents from R(sub rs) data alone, can be solved using the a(sub theta) functions without prior knowledge of the in-water optical properties. More importantly, this method avoids problems associated with a need for knowledge of the shape

  10. Active tuning of epsilon-near-zero point of hyperbolic metamaterial at visible and near-infrared regimes

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Zhao, Hua; Su, Hang; Hu, Guangwei; Zhang, Jingwen

    2016-09-01

    An active method of continuously tuning the effective permittivity of a hyperbolic metamaterial at visible and near-infrared spectra is introduced in this letter. A transparent conducting oxide, whose optical properties can be altered accurately by applying an external voltage, is inserted into a traditional metal-dielectric multilayer structure to increase the degree of freedom for tuning the epsilon-near-zero point by shifting the topological transition point. The tuning effect is explained in detail by combining the relationship between permittivity and voltage with wavevector analysis. This may promote other active applications of hyperbolic metamaterials and ultrafast tunable optoelectronic devices.

  11. Visible infrared spin-scan radiometers (VISSR) for the Geostationary Operational Environmental Satellite (GOES) B and C application

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Two visible infrared spin scan radiometer (VISSR) instruments provided for the Geostationary Operational Environmental Satellite B and C (GOES B and C) spacecrafts are described. The instruments are identical to those supplied previously are summarized. A significant number of changes primarily involving corrections of drawing errors and omissions were also performed. All electrical changes were breadboarded (where complexity required this), were incorporated into the test module, and subjected to verification of proper operation throughout fall instrument temperature range. Evaluation of the changes also included design operating safety margins to account for component variations and life.

  12. Visible and infrared mapping spectrometer for exploration of comets, asteroids, and the Saturnian system of rings and moons

    NASA Technical Reports Server (NTRS)

    Juergens, David W.; Duval, James E.; Lockhart, Robert F.; Langevin, Yves; Formisano, Vittorio; Bellucci, Giancarlo

    1991-01-01

    Consideration is given to a visible and infrared mapping spectrometer (VIMS) developed by American, Italian, and French scientists and engineers as a facility instrument for the Comet Rendezvous Asteroid Flyby (CRAF) mission and as a candidate facility instrument for the Cassini mission to explore Saturn and its rings and moons. VIMS is characterized by 0.35-5.2 micron spectral range with a nominal spatial resolution of 0.5 mrad and spectral resolutions of 7 nm at 0.35-1.0 micron wavelength and 16 nm at 1.0-5.2 micron wavelength.

  13. Simultaneous seeing measurement through the Subaru Telescope in the visible and near-infrared bands for the wavelength dependence evaluation

    NASA Astrophysics Data System (ADS)

    Oya, Shin; Terada, Hiroshi; Hayano, Yutaka; Watanabe, Makoto; Hattori, Masayuki; Minowa, Yosuke

    2016-08-01

    Stellar images have been obtained under natural seeing at visible and near-infrared wavelengths simultaneously through the Subaru Telescope at Mauna Kea. The image quality is evaluated by the full-width at the half-maximum (FWHM) of the stellar images. The observed ratio of FWHM in the V-band to the K-band is 1.54 ± 0.17 on average. The ratio shows tendency to decrease toward bad seeing as expected from the outer scale influence, though the number of the samples is still limited. The ratio is important for simulations to evaluate the performance of a ground-layer adaptive optics system at near-infrared wavelengths based on optical seeing statistics. The observed optical seeing is also compared with outside seeing to estimate the dome seeing of the Subaru Telescope.

  14. Imaging magnetographs for high-resolution solar observations in the visible and near-infrared wavelength region

    NASA Astrophysics Data System (ADS)

    Denker, C.; Didkovsky, L.; Ma, J.; Shumko, S.; Varsik, J.; Wang, J.; Wang, H.; Goode, P. R.

    The Coudé feed of the vacuum telescope (aperture D=65 cm) at the Big Bear Solar Observatory (BBSO) is currently completely remodelled to accommodate a correlation tracker and a high-order Adaptive Optics (AO) system. The AO system serves two imaging magnetograph systems located at a new optical laboratory on the observatory's 2nd floor. The InfraRed Imaging Magnetograph (IRIM) is an innovative magnetograph system for near-infrared (NIR) observations in the wavelength region from 1.0 mu m to 1.6 mu m. The Visible-light Imaging Magnetograph (VIM) is basically a twin of IRIM for observations in the wavelength range from 550 nm to 700 nm. Both instruments were designed for high spatial and high temporal observations of the solar photosphere and chromosphere. Real-time data processing is an integral part of the instruments and will enhance BBSO's capabilities in monitoring solar activity and predicting and forecasting space weather.

  15. Stray light test station for measuring point source transmission and thermal background of visible and infrared sensors

    NASA Astrophysics Data System (ADS)

    Peterson, Gary L.

    2008-08-01

    Breault Research Organization has designed and built a stray light test station. The station measures the point source transmission and background thermal irradiance of visible and infrared sensors. Two beam expanders, including a large 0.89 meter spherical mirror, expand and collimate light from laser sources at 0.658 and 10.6 µm. The large mirror is mounted on a gimbal to illuminate sensors at off-axis angles from 0° to 10°, and azimuths from 0° to 180°. Sensors with apertures as large as 0.3 meters can be tested with the existing facility. The large mirror is placed within a vacuum chamber so cryogenic infrared sensors can be tested in a vacuum environment. A dark cryogenic cold plate can be translated into the field of view of a sensor to measure its background thermal irradiance.

  16. Airborne Imagery

    NASA Technical Reports Server (NTRS)

    1983-01-01

    ATM (Airborne Thematic Mapper) was developed for NSTL (National Space Technology Companies) by Daedalus Company. It offers expanded capabilities for timely, accurate and cost effective identification of areas with prospecting potential. A related system is TIMS, Thermal Infrared Multispectral Scanner. Originating from Landsat 4, it is also used for agricultural studies, etc.

  17. Ultrafast Nonlinear Excitation Dynamics of Black Phosphorus Nanosheets from Visible to Mid-Infrared.

    PubMed

    Wang, Kangpeng; Szydłowska, Beata M; Wang, Gaozhong; Zhang, Xiaoyan; Wang, Jing Jing; Magan, John J; Zhang, Long; Coleman, Jonathan N; Wang, Jun; Blau, Werner J

    2016-07-26

    The recent progress on black phosphorus makes it a promising candidate material for broadband nanophotonic devices, especially operating in the mid-infrared spectral region. Here, the excited carrier dynamics and nonlinear optical response of unoxidized black phosphorus nanosheets and their wavelength dependence were systematically studied from 800 nm to 2.1 μm. The wavelength-dependent relaxation times of black phosphorus nanosheets are determined to be 360 fs to 1.36 ps with photon energies from 1.55 to 0.61 eV. In a comparative study with graphene, we found that black phosphorus has a faster carrier relaxation in near- and mid-infrared region. With regard to nonlinear optical absorption, the response of black phosphorus significantly increases from near- to mid-infrared, and black phosphorus is also confirmed to be better as saturable absorber to MoS2 in infrared region. PMID:27281449

  18. Ultrafast Nonlinear Excitation Dynamics of Black Phosphorus Nanosheets from Visible to Mid-Infrared.

    PubMed

    Wang, Kangpeng; Szydłowska, Beata M; Wang, Gaozhong; Zhang, Xiaoyan; Wang, Jing Jing; Magan, John J; Zhang, Long; Coleman, Jonathan N; Wang, Jun; Blau, Werner J

    2016-07-26

    The recent progress on black phosphorus makes it a promising candidate material for broadband nanophotonic devices, especially operating in the mid-infrared spectral region. Here, the excited carrier dynamics and nonlinear optical response of unoxidized black phosphorus nanosheets and their wavelength dependence were systematically studied from 800 nm to 2.1 μm. The wavelength-dependent relaxation times of black phosphorus nanosheets are determined to be 360 fs to 1.36 ps with photon energies from 1.55 to 0.61 eV. In a comparative study with graphene, we found that black phosphorus has a faster carrier relaxation in near- and mid-infrared region. With regard to nonlinear optical absorption, the response of black phosphorus significantly increases from near- to mid-infrared, and black phosphorus is also confirmed to be better as saturable absorber to MoS2 in infrared region.

  19. The Cytotoxic Effects of Low Intensity Visible and Infrared Light on Human Breast Cancer (MCF7) cells.

    PubMed

    Peidaee, P; Almansour, N; Shukla, R; Pirogova, E

    2013-01-01

    A concept of using low intensity light therapy (LILT) as an alternative approach to cancer treatment is at early stages of development; while the therapeutic effects of LILT as a non-invasive treatment modality for localized joint and soft tissue wound healing are widely corroborated. The LEDs-based exposure system was designed and constructed to irradiate the selected cancer and normal cells and evaluate the biological effects induced by light exposures in visible and infrared light range. In this study, human breast cancer (MCF7) cells and human epidermal melanocytes (HEM) cells (control) were exposed to selected far infrared light (3400nm, 3600nm, 3800nm, 3900nm, 4100nm and 4300nm) and visible and near infrared wavelengths (466nm, 585nm, 626nm, 810nm, 850nm and 950nm). The optical intensities of LEDs used for exposures were in the range of 15µW to 30µW. Cellular morphological changes of exposed and sham-exposed cells were evaluated using light microscopy. The cytotoxic effects of these low intensity light exposures on human cancer and normal cell lines were quantitatively determined by Lactate dehydrogenase (LDH) cytotoxic activity and PrestoBlue™ cell viability assays. Findings reveal that far-infrared exposures were able to reduce cell viability of MCF7 cells as measured by increased LDH release activity and PrestoBlue™ assays. Further investigation of the effects of light irradiation on different types of cancer cells, study of possible signaling pathways affected by electromagnetic radiation (EMR) and in vivo experimentation are required in order to draw a firm conclusion about the efficacy of low intensity light as an alternative non-invasive cancer treatment.

  20. [Development of a Surgical Navigation System with Beam Split and Fusion of the Visible and Near-Infrared Fluorescence].

    PubMed

    Yang, Xiaofeng; Wu, Wei; Wang, Guoan

    2015-04-01

    This paper presents a surgical optical navigation system with non-invasive, real-time, and positioning characteristics for open surgical procedure. The design was based on the principle of near-infrared fluorescence molecular imaging. The in vivo fluorescence excitation technology, multi-channel spectral camera technology and image fusion software technology were used. Visible and near-infrared light ring LED excitation source, multi-channel band pass filters, spectral camera 2 CCD optical sensor technology and computer systems were integrated, and, as a result, a new surgical optical navigation system was successfully developed. When the near-infrared fluorescence was injected, the system could display anatomical images of the tissue surface and near-infrared fluorescent functional images of surgical field simultaneously. The system can identify the lymphatic vessels, lymph node, tumor edge which doctor cannot find out with naked eye intra-operatively. Our research will guide effectively the surgeon to remove the tumor tissue to improve significantly the success rate of surgery. The technologies have obtained a national patent, with patent No. ZI. 2011 1 0292374. 1. PMID:26211271

  1. Small craft identification discrimination criteria N 50 and V 50 for visible and infrared sensors in maritime security

    NASA Astrophysics Data System (ADS)

    Krapels, Keith; Deaver, Dawne; Driggers, Ronald

    2006-09-01

    The new emphasis on Anti-Terrorism and Force Protection (AT/FP), for both shore and sea platform protection, has resulted in a need for infrared imager design and evaluation tools which demonstrate field performance against U.S. Navy AT/FP requirements. In the design of infrared imaging systems for target acquisition, a discrimination criterion is required for successful sensor realization. It characterizes the difficulty of the task being performed by the observer and varies for different target sets. This criterion is used in both assessment of existing infrared sensor and in the design of new conceptual sensors. In this experiment, we collected 12 small craft signatures (military and civilian) in the visible band during the day and the LWIR and MWIR spectra in both the day and the night environments. These signatures were processed to determine the targets' characteristic dimension and contrast. They were also processed to bandlimit the signature's spatial information content (simulating longer range) and a perception experiment was performed to determine the task difficulty (N 50 and V 50). The results are presented in this paper and can be used for Navy and Coast Guard imaging infrared sensor design and evaluation.

  2. Method And Apparatus For Examining A Tissue Using The Spectral Wing Emission Therefrom Induced By Visible To Infrared Photoexcitation.

    DOEpatents

    Alfano, Robert R.; Demos, Stavros G.; Zhang, Gang

    2003-12-16

    Method and an apparatus for examining a tissue using the spectral wing emission therefrom induced by visible to infrared photoexcitation. In one aspect, the method is used to characterize the condition of a tissue sample and comprises the steps of (a) photoexciting the tissue sample with substantially monochromatic light having a wavelength of at least 600 nm; and (b) using the resultant far red and near infrared spectral wing emission (SW) emitted from the tissue sample to characterize the condition of the tissue sample. In one embodiment, the substantially monochromatic photoexciting light is a continuous beam of light, and the resultant steady-state far red and near infrared SW emission from the tissue sample is used to characterize the condition of the tissue sample. In another embodiment, the substantially monochromatic photoexciting light is a light pulse, and the resultant time-resolved far red and near infrared SW emission emitted from the tissue sample is used to characterize the condition of the tissue sample. In still another embodiment, the substantially monochromatic photoexciting light is a polarized light pulse, and the parallel and perpendicular components of the resultant polarized time-resolved SW emission emitted from the tissue sample are used to characterize the condition of the tissue sample.

  3. Infrared-to-visible upconversion luminescence in neodymium-doped bismuth-borate glass

    NASA Astrophysics Data System (ADS)

    Oprea, Isabella-Ioana; Hesse, Hartmut; Betzler, Klaus

    2005-10-01

    The upconversion luminescence in Nd3+-doped bismuth-borate glass, excited by 0.8 μm light, was studied in the visible spectral region. Four distinct emission bands were found. From their kinetics, two mechanisms can be shown to be responsible for all four lines: energy-transfer upconversion, slightly dominating, and excited state absorption.

  4. A high performance, visible to mid-infrared photodetector based on graphene nanoribbons passivated with HfO2.

    PubMed

    Yu, Xuechao; Dong, Zhaogang; Liu, Yanping; Liu, Tao; Tao, Jin; Zeng, Yongquan; Yang, Joel K W; Wang, Qi Jie

    2016-01-01

    Graphene has drawn tremendous attention as a promising candidate for electronic and optoelectronic applications owing to its extraordinary properties, such as broadband absorption and ultrahigh mobility. Nevertheless, the absence of a bandgap makes graphene unfavorable for digital electronic or photonic applications. Although patterning graphene into nanostructures with the quantum confinement effect is able to open a bandgap, devices based on these graphene nanostructures generally suffer from low carrier mobility and scattering losses. In this paper, we demonstrated that encapsulation of an atomic layer deposited high-quality HfO2 film will greatly enhance the carrier mobility and decrease the scattering losses of graphene nanoribbons, because this high-k dielectric layer weakens carrier coulombic interactions. In addition, a photodetector based on HfO2 layer capped graphene nanoribbons can cover broadband wavelengths from visible to mid-infrared at room temperature, exhibiting ∼10 times higher responsivity than the one without a HfO2 layer in the visible regime and ∼8 times higher responsivity in the mid-infrared regime. The method employed here could be potentially used as a general approach to improve the performance of graphene nanostructures for electronic and optoelectronic applications. PMID:26610363

  5. Optimum combinations of visible and near-infrared reflectances for estimating the fraction of photosynthetically available radiation absorbed by plants

    NASA Technical Reports Server (NTRS)

    Podaire, Alain; Deschamps, Pierre-Yves; Frouin, R.; Asrar, Ghassem

    1991-01-01

    A useful parameter to estimate terrestrial primary productivity, that can be sensed from space, is the daily averaged fraction of Photosynthetically Available Radiation (PAR) absorbed by plants. To evaluate this parameter, investigators have relied on the fact that the relative amount of radiation reflected by a vegetated surface in the visible and near infrared depends on the fraction of the surface covered by the vegetation and therefore, correlates with absorbed PAR. They have used vegetation indices, namely normalized difference and simple ratio, to derive absorbed PAR. The problem with normalized difference and simple ratio is first, they are non linear functions of radiance or reflectance and therefore, cannot be readily applied to heterogeneous targets, second, they are used in generally nonlinear relationships, which make time integrals of the indices not proportional to primary productivity, and third, the relationships depend strongly on the type of canopy and background. To remove these limitations, linear combinations of visible and near infrared reflectances at optimum (one or two) viewing zenith angles are proposed.

  6. Monitoring light-induced structural changes of Channelrhodopsin-2 by UV-visible and Fourier transform infrared spectroscopy.

    PubMed

    Ritter, Eglof; Stehfest, Katja; Berndt, Andre; Hegemann, Peter; Bartl, Franz J

    2008-12-12

    Channelrhodopsin-2 (ChR2) is a microbial type rhodopsin and a light-gated cation channel that controls phototaxis in Chlamydomonas. We expressed ChR2 in COS-cells, purified it, and subsequently investigated this unusual photoreceptor by flash photolysis and UV-visible and Fourier transform infrared difference spectroscopy. Several transient photoproducts of the wild type ChR2 were identified, and their kinetics and molecular properties were compared with those of the ChR2 mutant E90Q. Based on the spectroscopic data we developed a model of the photocycle comprising six distinguishable intermediates. This photocycle shows similarities to the photocycle of the ChR2-related Channelrhodopsin of Volvox but also displays significant differences. We show that molecular changes include retinal isomerization, changes in hydrogen bonding of carboxylic acids, and large alterations of the protein backbone structure. These alterations are stronger than those observed in the photocycle of other microbial rhodopsins like bacteriorhodopsin and are related to those occurring in animal rhodopsins. UV-visible and Fourier transform infrared difference spectroscopy revealed two late intermediates with different time constants of tau = 6 and 40 s that exist during the recovery of the dark state. The carboxylic side chain of Glu(90) is involved in the slow transition. The molecular changes during the ChR2 photocycle are discussed with respect to other members of the rhodopsin family. PMID:18927082

  7. Capsaicinoids content prediction model development for Korean red-pepper powder using a visible and near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Lim, Jongguk; Mo, Changyeun; Noh, Sang Ha; Kang, Sukwon; Lee, Kangjin; Kim, Moon S.

    2012-05-01

    A nondestructive, real-time pungency measuring system with visible and near-infrared spectroscopy has been recently developed to measure capsaicinoids content in Korean red-pepper powder. One hundred twenty-five red-pepper powder samples produced from 11 regions in Republic of Korea were used for this investigation. The visible and near-infrared absorption spectra in the range from 450 to 950 nm were acquired and used for the development of prediction models of capsaicinoids contents in red-pepper powders without any chemical pretreatment to the samples. Partial Least Squares Regression (PLSR) models were developed to predict the regional capsaicinoids contents using the acquired absorption spectra. The chemical analysis of the total capsaicinoids (capsaicin and dihydrocapsaicin) was performed by a high performance liquid chromatographic (HPLC) method. The determination coefficient of validation (RV 2) and the standard error of prediction (SEP) for the capsaicinoids content prediction model, for a representative region in this study, were 0.9585 and +/-10.147 mg/100g, respectively.

  8. Waves of the Future (for Mars): In-Situ Mid-infrared, Near-infrared, and Visible Spectroscopic Analysis of Antarctic Cryptoendolithic Communities.

    NASA Astrophysics Data System (ADS)

    Hand, K. P.; Calrson, R.; Sun, H.; Anderson, M.; Wynn, W.; Levy, R.

    2005-12-01

    We have analyzed both the surface expression and depth profile of cryptoendolithic microbial communities at Battleship Promontory, in the Dry Valleys of Antarctica. Data was collected on site with an active mid-infrared Fourier transform microspectrometer (2.6 - 15 um), a near-infrared spectrometer (0.9-1.8 um), and a visible spectrometer (0.4-1 um). The trio of instruments are connected to microscopes that yield ~1 mm2 spatial resolution on the sample and they are mounted on two perpendicular motorized stages that allow for spatial scanning over an area of ~2cm2. Here we present results on the surface expression of the subsurface microbes in these three spectral regions and we present results on the analysis of a colonized sample examined in cross section. The former case has direct application to the remote, robotic detection of life within the rocks of Mars and the later case provides fundamental insights into the geological and biological interactions that make the Antarctic cryptoendolithic ecosystems possible. Non-invasive surface detection of cyanobacterial dominated communities was possible through the observation of several distinct bands: the carbon-hydrogen stretching modes (symmetric and asymmetric) for CH, CH2, and CH3 in the regions of 3.3-3.6 um and 3.6-3.7 um; the NH2 scissoring and C=O stretch near 6.0 um; the amide I of beta-pleated structures at ~6.1 um; and the 6.4 um - 6.6 um bands of N-H in plane bend of the amide II functional group. In combination, these bands make a strong case for carbohydrates and proteins associated with life. Not surprisingly, as the integrity of the amorphous silica surface varnish improved, our ability to detected the subsurface biosignature decreased. We note, however, that by utilizing the JPL rock crusher in Antarctica, a device designed to fly on the Mars Science Laboratory mission, the mid-infrared biosignature was easily detected. In the cross-section analysis the mid-infrared data provide a depth profile

  9. Near-opposition martian limb-darkening: Quantification and implication for visible-near-infrared bidirectional reflectance studies.

    NASA Astrophysics Data System (ADS)

    de Grenier, Muriel; Pinet, Patrick C.

    1995-06-01

    A nearly global coverage of the martian eastern hemisphere, acquired under small phase angles and varying observational geometries conditions, has been produced from 1988 opposition by spectral (0.5-1 μm) imaging data obtained at the Pic du Midi Observatory in France. From this data set, the methodology presented here permits a systematic analysis of martian photometric behavior at a regional scale of 100-300 km in the visible and near-infrared. The quantification of limb-darkening as a function of wavelength and surface albedo gives access in martian regional properties as a function of wavelength and surface albedo and results in the production of visible and near-infrared geometric albedo maps. A linear relation between the limb darkening parameter k and geometric albedo exists in the near infrared. Based on laboratory studies, it suggests a spectral response of particulate type for the martian soil. Conversely, in the visible, the value of k parameter is 0.6 independent of albedo and is consistent with a single scattering photometric behavior in the surface layer. However, the observed change in the martian photometry from single to multiple scattering may be partially due to a large contribution of atmospheric scattering above 0.7 μm. In the absence of a multitemporal dataset analysis, it must be emphasized that the present results are a priori only pertinent to the atmospheric and surface conditions existing on Mars at the time of observation. However, this analysis may contribute to characterize some physical properties, such as surface roughness. In the near-infrared, for bright terrains, k tends to 0.8 and agrees with the presence of very fine particulate materials. Photometry of dark areas is more irregular (0.48 < k < 0.64) and might result from surface roughness heterogeneities. However, a few dark areas reveal that k anomalous values in the range 0.7-0.8 may be caused by the presence of a coating of very fine materials or duricrust. Finally, we

  10. Evidence for subsidence in the 1989 Arctic winter stratosphere from airborne infrared composition measurements

    NASA Technical Reports Server (NTRS)

    Toon, G. C.; Farmer, C. B.; Schaper, P. W.; Lowes, L. L.; Norton, R. H.; Schoeberl, M. R.; Lait, L. R.; Newman, P. A.

    1992-01-01

    Simultaneous measurements of the stratospheric burdens of CO2, HCN, N2O, CH4, OCS, CF2Cl2, CFCl3, CHF2Cl and HF were made by the Jet propulsion Laboratory MkIV interferometer on board the NASA DC-8 aircraft during January and early February 1989 as part of the Airborne Arctic Stratosphere Experiment. Data were acquired on 11 flights at altitudes of up to 12 km over a geographic region covering the NE Atlantic Ocean, Iceland and Greenland. The results obtained show large variations in the burdens of these tracers due to the effects of transport. The tropospheric source gas burdens were reduced inside the polar vortex, suggesting that the air had subsided with respect to the surrounding midlatitude air. Increased HF burdens inside the vortex support this interpretation. The results obtained from the different tracers are highly consistent with each other and indicate that in the 15- to 20-km altitude range inside the vortex, surfaces of constant volume mixing ratio were located some 5-6 km lower in absolute altitude than outside the vortex. The results also indicate that the magnitude of this subsidence increases with altitude. These conclusions are consistent with other measurements.

  11. Composition measurements of the 1989 Arctic winter stratosphere by airborne infrared solar absorption spectroscopy

    NASA Technical Reports Server (NTRS)

    Toon, G. C.; Farmer, C. B.; Schaper, P. W.; Lowes, L. L.; Norton, R. H.

    1992-01-01

    The paper reports simultaneous measurements of the stratospheric burdens of H2O, HDO, OCS, CO2, O3, N2O, CO, CH4, CF2Cl2, CFCl3, CHF2Cl, C2H6, HCN, NO, NO2, HNO3, ClNO3, HOCl, HCl, and HF made by the JPL MkIV interferometer on board the NASA DC-8 aircraft during January and early February 1989 as part of the Airborne Arctic Stratosphere Experiment. Data were obtained on 11 flights at altitudes of up to 12 km over a geographic region covering the NE Atlantic Ocean, Iceland, and Greenland. Analyses of the chemically active gases reveal highly perturbed conditions within the vortex. The ClNO3 abundance was chemically enhanced near the edge of the vortex but was then depleted inside. NO2 was severely depleted inside the vortex. In contrast to Antarctica, H2O and HNO3 were both more abundant inside the vortex than outside. It is suggested that although the Arctic vortex did not get cold enough to produce any dehydration, or as vertically extensive denitrification as occurred in Antarctica, nevertheless, enough heterogeneous chemistry occurred to convert over 90 percent of the inorganic chlorine to active forms in the 14- to 27-km altitude range by early February 1989.

  12. Geological characterization of remote field sites using visible and infrared spectroscopy: Results from the 1999 Marsokhod field test

    USGS Publications Warehouse

    Johnson, J. R.; Ruff, S.W.; Moersch, J.; Roush, T.; Horton, K.; Bishop, J.; Cabrol, N.A.; Cockell, C.; Gazis, P.; Newsom, Horton E.; Stoker, C.

    2001-01-01

    Upcoming Mars Surveyor lander missions will include extensive spectroscopic capabilities designed to improve interpretations of the mineralogy and geology of landing sites on Mars. The 1999 Marsokhod Field Experiment (MFE) was a Mars rover simulation designed in part to investigate the utility of visible/near-infrared and thermal infrared field spectrometers to contribute to the remote geological exploration of a Mars analog field site in the California Mojave Desert. The experiment simultaneously investigated the abilities of an off-site science team to effectively analyze and acquire useful imaging and spectroscopic data and to communicate efficiently with rover engineers and an on-site field team to provide meaningful input to rover operations and traverse planning. Experiences gained during the MFE regarding effective communication between different mission operation teams will be useful to upcoming Mars mission teams. Field spectra acquired during the MFE mission exhibited features interpreted at the time as indicative of carbonates (both dolomitic and calcitic), mafic rocks and associated weathering products, and silicic rocks with desert varnish-like coatings. The visible/near-infrared spectra also suggested the presence of organic compounds, including chlorophyll in one rock. Postmission laboratory petrologic and spectral analyses of returned samples confirmed that all rocks identified as carbonates using field measurements alone were calc-silicates and that chlorophyll associated with endolithic organisms was present in the one rock for which it was predicted. Rocks classified from field spectra as silicics and weathered mafics were recognized in the laboratory as metamorphosed monzonites and diorite schists. This discrepancy was likely due to rock coatings sampled by the field spectrometers compared to fresh rock interiors analyzed petrographically, in addition to somewhat different surfaces analyzed by laboratory thermal spectroscopy compared to field

  13. Comparison of human skin opto-thermal response to near-infrared and visible laser irradiations: a theoretical investigation

    NASA Astrophysics Data System (ADS)

    Dai, Tianhong; Pikkula, Brian M.; Wang, Lihong V.; Anvari, Bahman

    2004-11-01

    Near-infrared wavelengths are absorbed less by epidermal melanin, and penetrate deeper into human skin dermis and blood than visible wavelengths. Therefore, laser irradiation using near-infrared wavelengths may improve the therapeutic outcome of cutaneous hyper-vascular malformations in moderately to heavily pigmented skin patients and those with large-sized blood vessels or blood vessels extending deeply into the skin. A mathematical model composed of a Monte Carlo algorithm to estimate the distribution of absorbed light, numerical solution of a bio-heat diffusion equation to calculate the transient temperature distribution, and a damage integral based on an empirical Arrhenius relationship to quantify the tissue damage was utilized to investigate the opto-thermal response of human skin to near-infrared and visible laser irradiations in conjunction with cryogen spray cooling. In addition, the thermal effects of a single continuous laser pulse and micropulse-composed laser pulse profiles were compared. Simulation results indicated that a 940 nm wavelength induces improved therapeutic outcome compared with a 585 and 595 nm wavelengths for the treatment of patients with large-sized blood vessels and moderately to heavily pigmented skin. On the other hand, a 585 nm wavelength shows the best efficacy in treating small-sized blood vessels, as characterized by the largest laser-induced blood vessel damage depth compared with 595 and 940 nm wavelengths. Dermal blood content has a considerable effect on the threshold incident dosage for epidermal damage, while the effect of blood vessel size is minimal. For the same macropulse duration and incident dosage, a micropulse-composed pulse profile results in higher peak temperature at the basal layer of skin epidermis than an ideal single continuous pulse profile.

  14. Detection of oil slicks at night with airborne infrared imagers. Final report, October 1993-April 1994

    SciTech Connect

    Daniels, G.M.; Hover, G.L.

    1994-12-01

    The detection of oil slicks on the ocean is a Coast Guard priority. Daytime detection in clear weather is routine; but nighttime detection requires sophisticated imaging sensors. Infrared imagers have demonstrated some capability to detect oil slicks at night in the marine environment. Infrared imagers sense the thermal radiation, and its variations, in a scene rather than the reflected radiation. Gimbal-mounted thermal imagers operating in the 8-12 micron region are currently flown on Coast Guard aircraft. This study compared the performance of these imagers with hand-held imagers operating in the 3-5 micron region. The comparison was primarily theoretical with semi-quantitative support from an uncalibrated data base of infrared images taken wit various sensors. It was found theoretically, and supported by image data, that the 8-12 micron instruments produced images with better water-oil contrast at night. This differential behavior was theoretically predicted to hold over a wide range of environmental conditions. The differential behavior was traced to the fact that the optical properties of water and oil are more different in the 8-12 than in the 3-5 micron bands. The utility of night-vision imagers or low-light level TVs was also assessed. Calculations indicated that typical water-oil contrasts would not be seen with current sensors. Image data appearing to contradict this conclusion was found to be defective in the sense that the conditions of the experiments were not representative of operational conditions. It is recommended that: the use of 8-12 micron imagers be continued for oil slick searches at night and the potential of new night-time imaging devices be assessed.

  15. Identifying trout refuges in the Indian and Hudson Rivers in northern New York through airborne thermal infrared remote sensing

    USGS Publications Warehouse

    Ernst, Anne G.; Baldigo, Barry P.; Calef, Fred J.; Freehafer, Douglas A.; Kremens, Robert L.

    2015-10-09

    The locations and sizes of potential cold-water refuges for trout were examined in 2005 along a 27-kilometer segment of the Indian and Hudson Rivers in northern New York to evaluate the extent of refuges, the effects of routine flow releases from an impoundment, and how these refuges and releases might influence trout survival in reaches that otherwise would be thermally stressed. This river segment supports small populations of brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) and also receives regular releases of reservoir-surface waters to support rafting during the summer, when water temperatures in both the reservoir and the river frequently exceed thermal thresholds for trout survival. Airborne thermal infrared imaging was supplemented with continuous, in-stream temperature loggers to identify potential refuges that may be associated with tributary inflows or groundwater seeps and to define the extent to which the release flows decrease the size of existing refuges. In general, the release flows overwhelmed the refuge areas and greatly decreased the size and number of the areas. Mean water temperatures were unaffected by the releases, but small-scale heterogeneity was diminished. At a larger scale, water temperatures in the upper and lower segments of the reach were consistently warmer than in the middle segment, even during passage of release waters. The inability of remote thermal infrared images to consistently distinguish land from water (in shaded areas) and to detect groundwater seeps (away from the shallow edges of the stream) limited data analysis and the ability to identify potential thermal refuge areas.

  16. Identifying trout refuges in the Indian and Hudson Rivers in northern New York through airborne thermal infrared remote sensing

    USGS Publications Warehouse

    Ernst, Anne G.; Baldigo, Barry P.; Calef, Fred J.; Freehafer, Douglas A.; Kremens, Robert L.

    2015-01-01

    The locations and sizes of potential cold-water refuges for trout were examined in 2005 along a 27-kilometer segment of the Indian and Hudson Rivers in northern New York to evaluate the extent of refuges, the effects of routine flow releases from an impoundment, and how these refuges and releases might influence trout survival in reaches that otherwise would be thermally stressed. This river segment supports small populations of brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) and also receives regular releases of reservoir-surface waters to support rafting during the summer, when water temperatures in both the reservoir and the river frequently exceed thermal thresholds for trout survival. Airborne thermal infrared imaging was supplemented with continuous, in-stream temperature loggers to identify potential refuges that may be associated with tributary inflows or groundwater seeps and to define the extent to which the release flows decrease the size of existing refuges. In general, the release flows overwhelmed the refuge areas and greatly decreased the size and number of the areas. Mean water temperatures were unaffected by the releases, but small-scale heterogeneity was diminished. At a larger scale, water temperatures in the upper and lower segments of the reach were consistently warmer than in the middle segment, even during passage of release waters. The inability of remote thermal infrared images to consistently distinguish land from water (in shaded areas) and to detect groundwater seeps (away from the shallow edges of the stream) limited data analysis and the ability to identify potential thermal refuge areas.

  17. Simultaneous infrared and UV-visible absorption spectra of matrix-isolated carbon vapor

    NASA Technical Reports Server (NTRS)

    Kurtz, Joe; Huffman, Donald R.

    1989-01-01

    Carbon molecules were suggested as possible carriers of the diffuse interstellar bands. In particular, it was proposed that the 443 nm diffuse interstellar band is due to the same molecule which gives rise to the 447 nm absorption feature in argon matrix-isolated carbon vapor. If so, then an associated C-C stretching mode should be seen in the IR. By doing spectroscopy in both the IR and UV-visible regions on the same sample, the present work provides evidence for correlating UV-visible absorption features with those found in the IR. Early data indicates no correlation between the strongest IR feature (1997/cm) and the 447 nm band. Correlation with weaker IR features is being investigated.

  18. Emerging Techniques for Vicarious Calibration of Visible Through Short Wave Infrared Remote Sensing Systems

    NASA Technical Reports Server (NTRS)

    Ryan, Robert E.; Harrington, Gary; Holekamp, Kara; Pagnutti, Mary; Russell, Jeffrey; Frisbie, Troy; Stanley, Thomas

    2007-01-01

    Autonomous Visible to SWIR ground-based vicarious Cal/Val will be an essential Cal/Val component with such a large number of systems. Radiometrically calibrated spectroradiometers can improve confidence in current ground truth data through validation of radiometric modeling and validation or replacement of traditional sun photometer measurement. They also should enable significant reduction in deployed equipment such as equipment used in traditional sun photometer approaches. Simple, field-portable, white-light LED calibration source shows promise for visible range (420-750 nm). Prototype demonstrated <0.5% drift over 10-40 C temperature range. Additional complexity (more LEDs) will be necessary for extending spectral range into the NIR and SWIR. LED long lifetimes should produce at least several hundreds of hours or more of stability, minimizing the need for expensive calibrations and supporting long-duration field campaigns.

  19. Toward a UV-visible-near-infrared hyperspectral imaging platform for fast multiplex reflection spectroscopy.

    PubMed

    Li, Jianping; Chan, Robert K Y

    2010-10-15

    A reflection hyperspectral imaging system covering a 350-1000nm spectral range is realized by a UV-visible-near-IR Fourier transform imaging spectrometer. The system has a simple design and good spectral and spatial resolving performance. Accurate and fast microspectroscopic measurement results on novel colloidal crystal beads demonstrate the system has practical potential for high-throughput molecular multiplex assays. PMID:20967056

  20. Fabrication and characterization of silicone-based tissue phantoms with tunable optical properties in the visible and near infrared domain

    NASA Astrophysics Data System (ADS)

    Ayers, Frederick; Grant, Alex; Kuo, Danny; Cuccia, David J.; Durkin, Anthony J.

    2008-02-01

    We present a fabrication process for Polydimethylsiloxane (PDMS) tissue simulating phantoms with tunable optical properties to be used for optical system calibration and performance testing. Compared to liquid phantoms, cured PDMS phantoms are easier to transport and use, and have a longer usable life than gelatin based phantoms. Additionally, the deformability of cured PDMS makes it a better option over hard phantoms such as polyurethane optical phantoms when using optical probes which require tissue contact. PDMS has a refractive index of about 1.43 in the near infrared domain which is in the range of the refractive index of tissue. Absorption properties are determined through the addition of india ink, a broad band absorber in the visible and near infrared spectrum. Scattering properties are set by adding titanium dioxide, an inexpensive and widely available scattering agent which yields a wavelength dependent scattering coefficient similar to that observed in tissue in the near infrared. Phantom properties were characterized and validated using a two-distance, broadband frequency-domain photon migration system. Repeatability and predictability for the phantom fabrication process will be presented.

  1. Real-time sensor mapping display for airborne imaging sensor test with the adaptive infrared imaging spectroradiometer (AIRIS)

    NASA Astrophysics Data System (ADS)

    Burton, Megan M.; Cruger, William E.; Gittins, Christopher; Kindle, Harry; Ricks, Timothy P.

    2005-11-01

    Captive flight testing (CFT) of sensors and seekers requires accurate data collection and display for sensor performance evaluation. The U.S. Army Redstone Technical Test Center (RTTC), in support of the U.S. Army Edgewood Chemical Biological Center (ECBC), has developed a data collection suite to facilitate airborne test of hyperspectral chemical/biological sensors. The data collection suite combines global positioning system (GPS) tracking, inertial measurement unit (IMU) data, accurate timing streams, and other test scenario information. This data collection suite also contains an advanced real-time display of aircraft and sensor field-of-view information. The latest evolution of this system has been used in support of the Adaptive InfraRed Imaging Spectroradiometer (AIRIS), currently under development by Physical Sciences Incorporated for ECBC. For this test, images from the AIRIS sensor were overlaid on a digitized background of the test area, with latencies of 1 second or less. Detects of surrogate chemicals were displayed and geo-referenced. Video overlay was accurate and reliable. This software suite offers great versatility in the display of imaging sensor data; support of future tests with the AIRIS sensor are planned as the system evolves.

  2. Source Attribution of Methane Emission from Petroleum Production Operations using High-Resolution Airborne Thermal-Infrared Imaging Spectrometry

    NASA Astrophysics Data System (ADS)

    Tratt, D. M.; Buckland, K. N.; Young, S. J.; Riley, D.; Leifer, I.

    2012-12-01

    High spatio-spectral resolution airborne thermal-infrared (TIR) imaging spectrometry is shown to be effective in detecting and tracking gaseous emissions from petroleum production facilities. The high spatial resolution (1-2 m) of the sensor permits unequivocal trace-back of emission plumes to their source. The high spectral resolution (44 nm across the 7.5-13.5 μm TIR band) enables precise identification and discrimination of primary and subsidiary plume components through the application of spectral matched filtering and adaptive coherence estimation techniques. Operation in the TIR spectral region allows operations to be conducted throughout the diurnal cycle, since the measurement relies on observation of emissive radiation and the intrinsic thermal contrast between the fugitive plume gases and the underlying scene. Methane plumes associated with petroleum production operations and natural emissions have been identified in a variety of environmental settings. The accompanying figure shows a grayscale thermal image of a marine production platform off the California coast. A gas plume (identified as methane) being released from a venting boom is shown superimposed in false color.

  3. Photoreactivation in Airborne Mycobacterium parafortuitum

    PubMed Central

    Peccia, Jordan; Hernandez, Mark

    2001-01-01

    Photoreactivation was observed in airborne Mycobacterium parafortuitum exposed concurrently to UV radiation (254 nm) and visible light. Photoreactivation rates of airborne cells increased with increasing relative humidity (RH) and decreased with increasing UV dose. Under a constant UV dose with visible light absent, the UV inactivation rate of airborne M. parafortuitum cells decreased by a factor of 4 as RH increased from 40 to 95%; however, under identical conditions with visible light present, the UV inactivation rate of airborne cells decreased only by a factor of 2. When irradiated in the absence of visible light, cellular cyclobutane thymine dimer content of UV-irradiated airborne M. parafortuitum and Serratia marcescens increased in response to RH increases. Results suggest that, unlike in waterborne bacteria, cyclobutane thymine dimers are not the most significant form of UV-induced DNA damage incurred by airborne bacteria and that the distribution of DNA photoproducts incorporated into UV-irradiated airborne cells is a function of RH. PMID:11526027

  4. Prediction of leaf chemistry by the use of visible and near infrared reflectance spectroscopy

    NASA Technical Reports Server (NTRS)

    Card, Don H.; Peterson, David L.; Matson, Pamela A.; Aber, John D.

    1988-01-01

    The chemical content of dry, ground leaf material sampled from deciduous and conifer tree species from sites in Alaska, Wisconsin, and California was estimated using visible and shortwave IR spectroscopy. Seven chemical components - sugar, starch, protein, cellulose, total chlorophyll, lignin, and total nitrogen - were analyzed by wet chemical methods and their concentrations regressed against log 1/rho and first and second differences of log 1/rho (where rho is measured reflectance) at wavelengths selected by stepwise regression. Predictions of chemical concentrations based on cross validation suggest that this technique may be useful for extracting vegetation canopy biochemical information by remote sensing.

  5. Visible/Infrared Optical Depths of Cirrus as Seen by Satellite and Scanning Lidar

    NASA Technical Reports Server (NTRS)

    Wylie, Donald; Wolf, Walt; Piironen, Paivi; Eloranta, Edwin

    1996-01-01

    The High Spectral Resolution Lidar (HSRL) and the Volume Imaging Lidar (VIL) were combined to produce a quantitative image of the visible optical depth of cirrus clouds. The HSRL was used to calibrate the VIL signal into backscatter cross sections of particulates. The backscatter cross sections were related to extinction by a constant backscatter phase function determined from the HSRL data. This produced a three dimensional image of visual extinction in the cirrus clouds over a one hour period. Two lidar images were constructed from one hour VIL cross section records.

  6. Emerging Techniques for Vicarious Calibration of Visible Through Short Wave Infrared Remote Sensing Systems

    NASA Technical Reports Server (NTRS)

    Ryan, Robert E.

    2006-01-01

    Simple field-portable white light LED calibration source shows promise for visible range (420-750 nm) 1) Prototype demonstrated <0.5% drift over 10-40 C temperature range; 2) Additional complexity (more LEDs) will be necessary for extending spectral range into the NIR and SWIR; 3) LED long lifetimes should produce at least several hundreds of hours or more stability, minimizing need for expensive calibrations and supporting long-duration field campaigns; and 4) Enabling technology for developing autonomous sites.

  7. Integration of Multiple Plasmonic and Co-Catalyst Nanostructures on TiO2 Nanosheets for Visible-Near-Infrared Photocatalytic Hydrogen Evolution.

    PubMed

    Jiang, Wenya; Bai, Song; Wang, Limin; Wang, Xijun; Yang, Li; Li, Yanrui; Liu, Dong; Wang, Xiaonong; Li, Zhengquan; Jiang, Jun; Xiong, Yujie

    2016-03-23

    Utilization of visible and near-infrared light has always been the pursuit of photocatalysis research. In this article, an approach is developed to integrate dual plasmonic nanostructures with TiO2 semiconductor nanosheets for photocatalytic hydrogen production in visible and near-infrared spectral regions. Specifically, the Au nanocubes and nanocages used in this work can harvest visible and near-infrared light, respectively, and generate and inject hot electrons into TiO2 . Meanwhile, Pd nanocubes that can trap the energetic electrons from TiO2 and efficiently participate in the hydrogen evolution reaction are employed as co-catalysts for improved catalytic activity. Enabled by this unique integration design, the hydrogen production rate achieved is dramatically higher than those of its counterpart structures. This work represents a step toward the rational design of semiconductor-metal hybrid structures for broad-spectrum photocatalysis.

  8. A Wavelength Optimization Study on Visible and Infrared Propagation Systems in Coastal Environments

    NASA Technical Reports Server (NTRS)

    Reid, J. S.; Tsay, Si-Chee; Moision, W. K.; Gasso, S.; Cook, J. R.; Westphal, D. L.; Paulus, R. A.; Bucholtz, A.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Electro-optical (EO) systems employed for communications, surveillance and weapons systems are commonly assessed in the North American and European continents. However, the atmospheric propagation environment in these regions is often dissimilar to most other parts of the world. In particular, atmospheric dust, industrial pollution, and smoke frequently reduce visibility to less than 5 km in Asia and South America significantly hampering EO system performance. Because atmospheric aerosol species vary considerably in size and chemistry, optimal wavelengths for EO systems vary from region to region. In this paper we examine the extinction effects from aerosol particles and water vapor on a regional basis. Theoretical studies are coupled with visibility and satellite climatologies to make an assessment for the coastal regions of the world. While longer wavelengths permit higher transmission by particles in regions significantly hampered by fine mode particles (such as industrial pollution and smoke), this advantage is commonly offset by high extinction values from water vapor. This offsetting effect is particularly strong in industrial and developing countries in the tropics and sub-tropics such as Southeast Asia and South America. Conversely, the advantage of low water vapor concentrations in longer wavelengths is offset by high mass-extinction efficiencies of atmospheric dust in this portion of the spectrum.

  9. Rapid identification of soil cadmium pollution risk at regional scale based on visible and near-infrared spectroscopy.

    PubMed

    Chen, Tao; Chang, Qingrui; Clevers, J G P W; Kooistra, L

    2015-11-01

    Soil heavy metal pollution due to long-term sewage irrigation is a serious environmental problem in many irrigation areas in northern China. Quickly identifying its pollution status is an important basis for remediation. Visible-near-infrared reflectance spectroscopy (VNIRS) provides a useful tool. In a case study, 76 soil samples were collected and their reflectance spectra were used to estimate cadmium (Cd) concentration by partial least squares regression (PLSR) and back propagation neural network (BPNN). To reduce noise, six pre-treatments were compared, in which orthogonal signal correction (OSC) was first used in soil Cd estimation. Spectral analysis and geostatistics were combined to identify Cd pollution hotspots. Results showed that Cd was accumulated in topsoil at the study area. OSC can effectively remove irrelevant information to improve prediction accuracy. More accurate estimation was achieved by applying a BPNN. Soil Cd pollution hotspots could be identified by interpolating the predicted values obtained from spectral estimates.

  10. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies

    PubMed Central

    Giannios, Panagiotis; Toutouzas, Konstantinos G.; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M.; Zografos, George C.; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools. PMID:27297034

  11. Effects of mercury on visible/near-infrared reflectance spectra of mustard spinach plants (Brassica rapa P.).

    PubMed

    Dunagan, Sarah C; Gilmore, Martha S; Varekamp, Johan C

    2007-07-01

    Mustard spinach plants were grown in mercury-spiked and contaminated soils collected in the field under controlled laboratory conditions over a full growth cycle to test if vegetation grown in these soils has discernible characteristics in visible/near-infrared (VNIR) spectra. Foliar Hg concentrations (0.174-3.993ppm) of the Mustard spinach plants were positively correlated with Hg concentration of soils and varied throughout the growing season. Equations relating foliar Hg concentration to spectral reflectance, its first derivative, and selected vegetation indices were generated using stepwise multiple linear regression. Significant correlations are found for limited wavelengths for specific treatments and dates. Ratio Vegetation Index (RVI) and Red Edge Position (REP) values of plants in Hg-spiked and field-contaminated soils are significantly lower relative to control plants during the early and middle portions of the growth cycle which may be related to lower chlorophyll abundance or functioning in Hg-contaminated plants.

  12. Wide angle and narrow-band asymmetric absorption in visible and near-infrared regime through lossy Bragg stacks

    PubMed Central

    Shu, Shiwei; Zhan, Yawen; Lee, Chris; Lu, Jian; Li, Yang Yang

    2016-01-01

    Absorber is an important component in various optical devices. Here we report a novel type of asymmetric absorber in the visible and near-infrared spectrum which is based on lossy Bragg stacks. The lossy Bragg stacks can achieve near-perfect absorption at one side and high reflection at the other within the narrow bands (several nm) of resonance wavelengths, whereas display almost identical absorption/reflection responses for the rest of the spectrum. Meanwhile, this interesting wavelength-selective asymmetric absorption behavior persists for wide angles, does not depend on polarization, and can be ascribed to the lossy characteristics of the Bragg stacks. Moreover, interesting Fano resonance with easily tailorable peak profiles can be realized using the lossy Bragg stacks. PMID:27251768

  13. Coherent octave spanning near-infrared and visible supercontinuum generation in all-normal dispersion photonic crystal fibers.

    PubMed

    Heidt, Alexander M; Hartung, Alexander; Bosman, Gurthwin W; Krok, Patrizia; Rohwer, Erich G; Schwoerer, Heinrich; Bartelt, Hartmut

    2011-02-14

    We present the first detailed demonstrations of octave-spanning SC generation in all-normal dispersion photonic crystal fibers (ANDi PCF) in the visible and near-infrared spectral regions. The resulting spectral profiles are extremely flat without significant fine structure and with excellent stability and coherence properties. The key benefit of SC generation in ANDi PCF is the conservation of a single ultrashort pulse in the time domain with smooth and recompressible phase distribution. For the first time we confirm the exceptional temporal properties of the generated SC pulses experimentally and demonstrate their applicability in ultrafast transient absorption spectroscopy. The experimental results are in excellent agreement with numerical simulations, which are used to illustrate the SC generation dynamics by self-phase modulation and optical wave breaking. To our knowledge, we present the broadest spectra generated in the normal dispersion regime of an optical fiber. PMID:21369202

  14. Apparatus for measuring the emittance of materials from far infrared to visible wavelengths in extreme conditions of temperature

    NASA Astrophysics Data System (ADS)

    De Sousa Meneses, D.; Melin, P.; del Campo, L.; Cosson, L.; Echegut, P.

    2015-03-01

    A computer controlled circular turntable equipped with a blackbody reference and an integrated axisymmetric heating system based on a CO2 laser is at the heart of the reported device. It allows performing emittance measurements in the spectral domain ranging from far infrared up to visible light and in a wide range of temperature. The apparatus includes two spectrometers and was built to achieve optimal experimental conditions of measurement, i.e. environmental stability and single optical path for the acquisition of the thermal fluxes. The specific design of the apparatus is firstly described; applied procedures for the characterization of the blackbody reference, laser heating and the retrieval of the emittance spectra are given after. Finally measurements obtained for ruby, NdGaO3 and platinum are presented to illustrate the capacities of the apparatus.

  15. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies.

    PubMed

    Giannios, Panagiotis; Toutouzas, Konstantinos G; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M; Zografos, George C; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools. PMID:27297034

  16. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies

    NASA Astrophysics Data System (ADS)

    Giannios, Panagiotis; Toutouzas, Konstantinos G.; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M.; Zografos, George C.; Moutzouris, Konstantinos

    2016-06-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools.

  17. Observation of enhanced visible and infrared emissions in photonic crystal thin-film light-emitting diodes

    SciTech Connect

    Cheung, Y. F.; Li, K. H.; Hui, R. S. Y.; Choi, H. W.

    2014-08-18

    Photonic crystals, in the form of closed-packed nano-pillar arrays patterned by nanosphere lithography, have been formed on the n-faces of InGaN thin-film vertical light-emitting diodes (LEDs). Through laser lift-off of the sapphire substrate, the thin-film LEDs conduct vertically with reduced dynamic resistances, as well as reduced thermal resistances. The photonic crystal plays a role in enhancing light extraction, not only at visible wavelengths but also at infrared wavelengths boosting heat radiation at high currents, so that heat-induced effects on internal quantum efficiencies are minimized. The observations are consistent with predictions from finite-difference time-domain simulations.

  18. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies.

    PubMed

    Giannios, Panagiotis; Toutouzas, Konstantinos G; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M; Zografos, George C; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools.

  19. Extinction of visible and infrared radiation in rain Comparison of theory and experiment

    NASA Technical Reports Server (NTRS)

    Ulbrich, C. W.; Atlas, D.

    1985-01-01

    A critical review is given of the experimental and theoretical results concerning the measurement of rainfall using optical extinction, i.e., the attenuation of radiation with wavelength less than or equal to that of the infrared band. It is shown that rainfall rates found from an empirical relation involving optical extinction generally display average deviations without regard for sign of only 25 percent when compared with those measured by raingages directly beneath the optical beam. It is also shown that the differences between experimental and theoretical results can be explained in terms of variations of the shape of the raindrop size distribution, i.e., deviations from exponentiality.

  20. Infrared, visible and ultraviolet absorptions of transition metal doped ZnS crystals with spin-polarized bands

    SciTech Connect

    Zhang, J.H.; Ding, J.W.; Cao, J.X.; Zhang, Y.L.

    2011-03-15

    The formation energies, electronic structures and optical properties of TM:ZnS systems (TM=Cr{sup 2+}, Mn{sup 2+}, Fe{sup 2+}, Co{sup 2+} and Ni{sup 2+}) are investigated by using the first principles method. It is found that the wurtzite and zinc-blende structures have about the same stability, and thus can coexist in the TM:ZnS system. From the wurtzite TM:ZnS, especially, a partially filled intermediate band (IB) is obtained at TM=Cr{sup 2+}, Ni{sup 2+} and Fe{sup 2+}, while it is absent at TM=Mn{sup 2+} and Co{sup 2+}. The additional absorptions are obtained in infrared, visible and ultraviolet (UV) regions, due to the completely spin-polarized IB at Fermi level. The results are very helpful for both the designs and applications of TM:ZnS opto-electronics devices, such as solar-cell prototype. -- Graphical abstract: Absorption coefficients of w-TM{sub x}Zn{sub 1-x}S crystals (TM=Cr{sup 2+}, Mn{sup 2+}, Fe{sup 2+}, Co{sup 2+} and Ni{sup 2+}) at x=0.028. The results may be helpful for the design and applications of TM:ZnS devices, especially for the new high efficiency solar-cell prototype, UV detector and UV LEDs. Display Omitted Research highlights: > It is found that the wurtzite and zinc-blende structures can coexist in TM:ZnS. > An intermediate band is obtained in TM:ZnS at TM=Cr{sup 2+}, Ni{sup 2+} and Fe{sup 2+}. > The absorption coefficients are obtained in infrared, visible and ultraviolet regions.

  1. [Application of visible/near-infrared spectroscopy to the determination of catalase and peroxidase content in barley leaves].

    PubMed

    Zhao, Yun; Zhang, Chu; Liu, Fei; Kong, Wen-Wen; He, Yong

    2014-09-01

    Visible/near-infrared spectroscopy was applied to determine the content of catalase (CAT) and peroxidase (POD) in barley leaves under the herbicide stress of propyl 4-(2-(4, 6-dimethoxypyrimidin-2-yloxy) benzylamino) benzoate (ZJ0273). The spectral data of the barley leaves in the range of 500-900 nm were preprocessed by moving average with 11 points. Seven outlier samples for CAT and 8 outlier samples for POD were detected and removed by Monte Carlo-partial least squares (MCPLS). PLS, least-squares support vector machine (LS-SVM) and extreme learning machine (ELM) models were built for both CAT and POD. ELM model obtained best results for CAT, with correlation coefficient of calibration (Rc) of 0.916 and correlation co-efficient of prediction (Rp) of 0.786. PLS model obtained best prediction results for POD, with Rc of 0.984 and Rp of 0.876. Successive projections algorithm (SPA) was applied to select 8 and 19 effective wavelengths for CAT and POD, respectively. PLS, LS-SVM and ELM models were built using the selected effective wavelengths of CAT and POD. ELM model performed best for CAT and POD prediction, with Rc of 0.928 and Rp of 0.790 for CAT and Rp of 0.965 and Rp of 0.941 for POD. The prediction results using the full spectral data and the effective wavelengths were quite close, and the prediction performance for POD was much better than the prediction performance for CAT, and the studies should be further explored to build more precise and more robust models for CAT and POD determination. The overall results indicated that it was feasible to use visible/near-infrared spectroscopy for CAT and POD content determination in barley leaves under the stress of ZJ0273.

  2. Evaluation of airborne thermal-infrared image data for monitoring aquatic habitats and cultural resources within the Grand Canyon

    USGS Publications Warehouse

    Davis, Philip A.

    2002-01-01

    This study examined thermal-infrared (TIR) image data acquired using the airborne Advanced Thematic Mapper (ATM) sensor in the afternoon of July 25th, 2000 over a portion of the Colorado River corridor to determine the capability of these 100-cm resolution data to address some biologic and cultural resource requirements for GCMRC. The requirements investigated included the mapping of warm backwaters that may serve as fish habitats and the detection (and monitoring) of archaeological structures and natural springs that occur on land. This report reviews the procedure for calibration of the airborne TIR data to obtain surface water temperatures and shows the results for various river reaches within the acquired river corridor. With respect to mapping warm backwater areas, our results show that TIR data need to be acquired with a gain setting that optimizes the range of temperatures found within the water to increase sensitivity of the resulting data to a level of 0.1 °C and to reduce scan-line noise. Data acquired within a two-hour window around maximum solar heating (1:30 PM) is recommended to provide maximum solar heating of the water and to minimize cooling effects of late-afternoon shadows. Ground-truth data within the temperature range of the warm backwaters are necessary for calibration of the TIR data. The ground-truth data need to be collected with good locational accuracy. The derived water-temperature data provide the capability for rapid, wide-area mapping of warm-water fish habitats using a threshold temperature for such habitats. The collected daytime TIR data were ineffective in mapping (detecting) both archaeological structures and natural springs (seeps). The inability of the daytime TIR data to detect archaeological structures is attributed to the low thermal sensitivity (0.3 °C) of the collected data. The detection of subtle thermal differences between geologic materials requires sensitivities of at least 0.1 °C, which can be obtained by most TIR

  3. Visible to short wavelength infrared In2Se3-nanoflake photodetector gated by a ferroelectric polymer

    NASA Astrophysics Data System (ADS)

    Wu, Guangjian; Wang, Xudong; Wang, Peng; Huang, Hai; Chen, Yan; Sun, Shuo; Shen, Hong; Lin, Tie; Wang, Jianlu; Zhang, Shangtao; Bian, Lifeng; Sun, Jinglan; Meng, Xiangjian; Chu, Junhao

    2016-09-01

    Photodetectors based on two-dimensional (2D) transition-metal dichalcogenides have been studied extensively in recent years. However, the detective spectral ranges, dark current and response time are still unsatisfactory, even under high gate and source–drain bias. In this work, the photodetectors of In2Se3 have been fabricated on a ferroelectric field effect transistor structure. Based on this structure, high performance photodetectors have been achieved with a broad photoresponse spectrum (visible to 1550 nm) and quick response (200 μs). Most importantly, with the intrinsic huge electric field derived from the polarization of ferroelectric polymer (P(VDF-TrFE)) gating, a low dark current of the photodetector can be achieved without additional gate bias. These studies present a crucial step for further practical applications for 2D semiconductors.

  4. Visible to infrared low temperature photoluminescence of rare earth doped bismuth germanate crystals.

    PubMed

    Canimoglu, A; Ayvacikli, M; Karabulut, Y; Karali, T; Can, N

    2016-05-01

    In this paper, the influence of a series of rare earth (Eu, Tm, Nd) and Cr ion doping on the optical properties of BGO was investigated by means of photoluminescence (PL) from visible to IR region in the 10-300K temperature range using different types of detectors, namely, photomultiplier tube (PMT), InGaAs (IGA), and Si. Several samples were investigated having dopants concentrations of 0.3wt%Nd, 0.4wt%Tm, 0.06wt% Cr and 3ppm Eu. The PL spectra of the samples showed different luminescence behaviour which is assigned to the 4f intra shell transition from rare earth ions. The temperature dependence of the PL from rare earth doped BGO crystals is also examined. PMID:26943903

  5. Visible to short wavelength infrared In2Se3-nanoflake photodetector gated by a ferroelectric polymer

    NASA Astrophysics Data System (ADS)

    Wu, Guangjian; Wang, Xudong; Wang, Peng; Huang, Hai; Chen, Yan; Sun, Shuo; Shen, Hong; Lin, Tie; Wang, Jianlu; Zhang, Shangtao; Bian, Lifeng; Sun, Jinglan; Meng, Xiangjian; Chu, Junhao

    2016-09-01

    Photodetectors based on two-dimensional (2D) transition-metal dichalcogenides have been studied extensively in recent years. However, the detective spectral ranges, dark current and response time are still unsatisfactory, even under high gate and source-drain bias. In this work, the photodetectors of In2Se3 have been fabricated on a ferroelectric field effect transistor structure. Based on this structure, high performance photodetectors have been achieved with a broad photoresponse spectrum (visible to 1550 nm) and quick response (200 μs). Most importantly, with the intrinsic huge electric field derived from the polarization of ferroelectric polymer (P(VDF-TrFE)) gating, a low dark current of the photodetector can be achieved without additional gate bias. These studies present a crucial step for further practical applications for 2D semiconductors.

  6. Visible to short wavelength infrared In2Se3-nanoflake photodetector gated by a ferroelectric polymer.

    PubMed

    Wu, Guangjian; Wang, Xudong; Wang, Peng; Huang, Hai; Chen, Yan; Sun, Shuo; Shen, Hong; Lin, Tie; Wang, Jianlu; Zhang, Shangtao; Bian, Lifeng; Sun, Jinglan; Meng, Xiangjian; Chu, Junhao

    2016-09-01

    Photodetectors based on two-dimensional (2D) transition-metal dichalcogenides have been studied extensively in recent years. However, the detective spectral ranges, dark current and response time are still unsatisfactory, even under high gate and source-drain bias. In this work, the photodetectors of In2Se3 have been fabricated on a ferroelectric field effect transistor structure. Based on this structure, high performance photodetectors have been achieved with a broad photoresponse spectrum (visible to 1550 nm) and quick response (200 μs). Most importantly, with the intrinsic huge electric field derived from the polarization of ferroelectric polymer (P(VDF-TrFE)) gating, a low dark current of the photodetector can be achieved without additional gate bias. These studies present a crucial step for further practical applications for 2D semiconductors. PMID:27478899

  7. Detecting Thermal Barrier Coating Delamination Using Visible and Near-Infrared Luminescence from Erbium-Doped Sublayers

    NASA Technical Reports Server (NTRS)

    Eldridge, J. I.; Bencic, T. J.; Martin, R. E.; Singh, J.; Wolfe, D. E.

    2007-01-01

    Nondestructive diagnostic tools are needed to monitor early stages of delamination progression in thermal barrier coatings (TBCs) because the risk of delamination induced coating failure will compromise engine performance and safety. Previous work has demonstrated that for TBCs composed of yttria-stabilized zirconia (YSZ), luminescence from a buried europium-doped sublayer can be utilized to identify the location of TBC delamination from the substantially higher luminescence intensity observed from the delaminated regions of the TBC. Luminescence measurements from buried europium-doped layers depend on sufficient transmittance of the 532 nm excitation and 606 nm emission wavelengths through the attenuating undoped YSZ overlayer to produce easily detected luminescence. In the present work, improved delamination indication is demonstrated using erbium-doped YSZ sublayers. For visible-wavelength luminescence, the erbium-doped sublayer offers the advantage of a very strong excitation peak at 517 nm that can be conveniently excited a 514 nm Ar ion laser. More importantly, the erbium-doped sublayer also produces near-infrared luminescence at 1550 nm that is effectively excited by a 980 nm laser diode. Both the 980 nm excitation and the 1550 nm emission are transmitted through the TBC with much less attenuation than visible wavelengths and therefore show great promise for delamination monitoring through thicker or more highly scattering TBCs. The application of this approach for both electron beam physical vapor deposited (EB-PVD) and plasma-sprayed TBCs is discussed.

  8. Visible and near-infrared photothermal catalyzed hydrogenation of gaseous CO2 over nanostructured Pd@Nb2O5

    DOE PAGES

    Jia, Jia; O'Brien, Paul G.; He, Le; Qiao, Qiao; Fei, Teng; Reyes, Laura M.; Burrow, Timothy E.; Dong, Yuchan; Liao, Kristine; Varela, Maria; et al

    2016-07-05

    The reverse water gas shift (RWGS) reaction driven by Nb2O5 nanorod-supported Pd nanocrystals without external heating using visible and near infrared (NIR) light is demonstrated. By measuring the dependence of the RWGS reaction rates on the intensity and spectral power distribution of filtered light incident onto the nanostructured Pd@Nb2O5 catalyst, it is determined that the RWGS reaction is activated photothermally. That is the RWGS reaction is initiated by heat generated from thermalization of charge carriers in the Pd nanocrystals that are excited by interband and intraband absorption of visible and NIR light. Taking advantage of this photothermal effect, a visiblemore » and NIR responsive Pd@Nb2O5 hybrid catalyst that efficiently hydrogenates CO2 to CO at an impressive rate as high as 1.8 mmol gcat–1 h–1 is developed. The mechanism of this photothermal reaction involves H2 dissociation on Pd nanocrystals and subsequent spillover of H to the Nb2O5 nanorods whereupon adsorbed CO2 is hydrogenated to CO. Here, this work represents a significant enhancement in our understanding of the underlying mechanism of photothermally driven CO2 reduction and will help guide the way toward the development of highly efficient catalysts that exploit the full solar spectrum to convert gas-phase CO2 to valuable chemicals and fuels.« less

  9. A Bi2 WO6 -based hybrid photocatalyst with broad spectrum photocatalytic properties under UV, visible, and near-infrared irradiation.

    PubMed

    Tian, Jian; Sang, Yuanhua; Yu, Guangwei; Jiang, Huaidong; Mu, Xiaoning; Liu, Hong

    2013-09-25

    Near-infrared active photocatalytic properties of Bi2 WO6 nanosheets owing to the oxygen vacancies of the Bi2 WO6 nanosheets are reported. The broad spectrum photocatalyst, Bi2 WO6 -TiO2 nanobelt heterostructures, are obtained by assembling Bi2 WO6 nanocrystals on TiO2 nanobelts. The active light band of the novel hybrid photocatalyst with high photocatalytic activity covers full-spectrum solar light including the UV, visible, and near-infrared ranges.

  10. Time-resolved visible and infrared study of the cyano complexes of myoglobin and of hemoglobin I from Lucina pectinata.

    PubMed

    Helbing, Jan; Bonacina, Luigi; Pietri, Ruth; Bredenbeck, Jens; Hamm, Peter; van Mourik, Frank; Chaussard, Frédéric; Gonzalez-Gonzalez, Alejandro; Chergui, Majed; Ramos-Alvarez, Cacimar; Ruiz, Carlos; López-Garriga, Juan

    2004-09-01

    The dynamics of the ferric CN complexes of the heme proteins Myoglobin and Hemoglobin I from the clam Lucina pectinata upon Soret band excitation is monitored using infrared and broad band visible pump-probe spectroscopy. The transient response in the UV-vis spectral region does not depend on the heme pocket environment and is very similar to that known for ferrous proteins. The main feature is an instantaneous, broad, short-lived absorption signal that develops into a narrower red-shifted Soret band. Significant transient absorption is also observed in the 360-390 nm range. At all probe wavelengths the signal decays to zero with a longest time constant of 3.6 ps. The infrared data on MbCN reveal a bleaching of the C triple bond N stretch vibration of the heme-bound ligand, and the formation of a five-times weaker transient absorption band, 28 cm(-1) lower in energy, within the time resolution of the experiment. The MbC triple bond N stretch vibration provides a direct measure for the return of population to the ligated electronic (and vibrational) ground state with a 3-4 ps time constant. In addition, the CN-stretch frequency is sensitive to the excitation of low frequency heme modes, and yields independent information about vibrational cooling, which occurs on the same timescale.

  11. Model-based deduction of CMYK surface coverages from visible and infrared spectral measurements of halftone prints

    NASA Astrophysics Data System (ADS)

    Bugnon, Thomas; Brichon, Mathieu; Hersch, Roger David

    2007-01-01

    The Yule-Nielsen modified Spectral Neugebauer reflection prediction model enhanced with an ink spreading model provides high accuracy when predicting reflectance spectra from ink surface coverages. In the present contribution, we try to inverse the model, i.e. to deduce the surface coverages of a printed color halftone patch from its measured reflectance spectrum. This process yields good results for cyan, magenta, and yellow inks, but unstable results when simultaneously fitting cyan, magenta, yellow, and black inks due to redundancy between these four inks: black can be obtained by printing either the black ink or similar amounts of the cyan, magenta, and yellow inks. To overcome this problem, we use the fact that the black pigmented ink absorbs light in the infrared domain, whereas cyan, magenta, and yellow inks do not. Therefore, with reflection spectra measurements spanning both the visible and infrared domain, it is possible to accurately deduce the black ink coverage. Since there is no redundancy anymore, the cyan, magenta, yellow, and pigmented black ink coverages can be recovered with high accuracy.

  12. Visible and near-infrared (0.4-2.5 μm) reflectance spectra of playa evaporite minerals

    USGS Publications Warehouse

    Crowley, James K.

    1991-01-01

    Visible and near-infrared (VNIR; 0.4–2.4 μm) reflectance spectra were recorded for 35 saline minerals that represent the wide range of mineral and brine chemical compositions found in playa evaporite settings. The spectra show that many of the saline minerals exhibit diagnostic near-infrared absorption bands, chiefly attributable to vibrations of hydrogen-bonded structural water molecules. VNIR reflectance spectra can be used to detect minor hydrate phases present in mixtures dominated by anhydrous halite or thenardite, and therefore will be useful in combination with X ray diffraction data for characterizing natural saline mineral assemblages. In addition, VNIR reflectance spectra are sensitive to differences in sample hydration state and should facilitate in situ studies of minerals that occur as fragile, transitory dehydration products in natural salt crusts. The use of spectral reflectance measurements in playa studies should aid in mapping evaporite mineral distributions and may provide insight into the geochemical and hydrological controls on playa mineral and brine development.

  13. Design and performance of 4 x 5120-element visible and 2 x 2560-element shortwave infrared multispectral focal planes

    NASA Technical Reports Server (NTRS)

    Tower, J. R.; Cope, A. D.; Pellon, L. E.; Mccarthy, B. M.; Strong, R. T.

    1986-01-01

    Two solid-state sensors for use in remote sensing instruments operating in the pushbroom mode are examined. The design and characteristics of the visible/near-infrared (VIS/NIR) device and the short-wavelength infrared (SWIR) device are described. The VIS/NIR is a CCD imager with four parallel sensor lines, each 1024 pixel long; the chip design and filter system of the VIS/NIR are studied. The performance of the VIS/NIR sensor with mask and its system performance are measured. The SWIR is a dual-band line imager consisting of palladium silicide Schottky-barrier detectors coupled to CCD multiplexers; the performance of the device is analyzed. The substrate materials and layout designs used to assemble the 4 x 5120-element VIS/NIR array and the 2 x 2560-element SWIR array are discussed, and the planarity of the butted arrays are verified using a profilometer. The optical and electrical characteristics, and the placement and butting accuracy of the arrays are evaluated. It is noted that the arrays met or exceed their expected performance.

  14. The added value of a visible channel to a geostationary thermal infrared instrument to monitor ozone for air quality

    NASA Astrophysics Data System (ADS)

    Hache, E.; Attié, J.-L.; Tourneur, C.; Ricaud, P.; Coret, L.; Lahoz, W. A.; El Amraoui, L.; Josse, B.; Hamer, P.; Warner, J.; Liu, X.; Chance, K.; Höpfner, M.; Spurr, R.; Natraj, V.; Kulawik, S.; Eldering, A.; Orphal, J.

    2014-02-01

    Ozone is a tropospheric pollutant and plays a key role in determining the air quality that affects human wellbeing. In this study, we compare the capability of two hypothetical grating spectrometers onboard a geostationary (GEO) satellite to sense ozone in the lowermost troposphere (surface and the 0-1 km column). We consider one week during the Northern Hemisphere summer simulated by a chemical transport model, and use the two GEO instrument configurations to measure ozone concentration (1) in the thermal infrared (GEO TIR) and (2) in the thermal infrared and the visible (GEO TIR+VIS). These configurations are compared against each other, and also against an ozone reference state and a priori ozone information. In a first approximation, we assume clear sky conditions neglecting the influence of aerosols and clouds. A number of statistical tests are used to assess the performance of the two GEO configurations. We consider land and sea pixels and whether differences between the two in the performance are significant. Results show that the GEO TIR+VIS configuration provides a better representation of the ozone field both for surface ozone and the 0-1 km ozone column during the daytime especially over land.

  15. The added value of a visible channel to a geostationary thermal infrared instrument to monitor ozone for air quality

    NASA Astrophysics Data System (ADS)

    Hache, E.; Attié, J.-L.; Tourneur, C.; Ricaud, P.; Coret, L.; Lahoz, W. A.; El Amraoui, L.; Josse, B.; Hamer, P.; Warner, J.; Liu, X.; Chance, K.; Höpfner, M.; Spurr, R.; Natraj, V.; Kulawik, S.; Eldering, A.; Orphal, J.

    2014-07-01

    Ozone is a tropospheric pollutant and plays a key role in determining the air quality that affects human wellbeing. In this study, we compare the capability of two hypothetical grating spectrometers onboard a geostationary (GEO) satellite to sense ozone in the lowermost troposphere (surface and the 0-1 km column). We consider 1 week during the Northern Hemisphere summer simulated by a chemical transport model, and use the two GEO instrument configurations to measure ozone concentration (1) in the thermal infrared (GEO TIR) and (2) in the thermal infrared and the visible (GEO TIR+VIS). These configurations are compared against each other, and also against an ozone reference state and a priori ozone information. In a first approximation, we assume clear sky conditions neglecting the influence of aerosols and clouds. A number of statistical tests are used to assess the performance of the two GEO configurations. We consider land and sea pixels and whether differences between the two in the performance are significant. Results show that the GEO TIR+VIS configuration provides a better representation of the ozone field both for surface ozone and the 0-1 km ozone column during the daytime especially over land.

  16. Comparison of two atmospheric correction models for a vegetated Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) scene

    NASA Technical Reports Server (NTRS)

    Vandenbosch, Jeannette Marie; Alley, R. E.

    1991-01-01

    Current atmospheric correction models applied to imaging spectroscopy data include such methods as residual (scene average) and flat field correction, regression method, and the LOWTRAN 7 method. Due to the limitations of using residual and flat field corrections on vegetated scenes, regression and LOWTRAN 7 are compared. Field measured targets taken at the time of the 13 April, 1989 AVIRIS overflight of Jasper Ridge, California (U.S.) were used to formulate the regression atmospheric correction. Assuming the regressed image represents ground truth, results show that the LOWTRAN 7 method with radiosonde data does not compensate as well for atmospheric water vapor as the regression method, but it may be easier to obtain a posteriori information to perform the LOWTRAN 7 atmospheric correction.

  17. Comparison of three atmospheric correction models for a vegetated airborne visible/infrared imaging spectrometer (AVIRIS) scene

    NASA Technical Reports Server (NTRS)

    Van Den Bosch, J. M.; Alley, R. E.

    1991-01-01

    Current atmospheric correction models applied to imaging spectroscopy data include such methods as residual or scene average, flat field correction, regression method or empirical line algorithm, the continuum interpolated band ratio (CIBR) derivation and the LOWTRAN 7 method. Due to the limitations of using residual and flat field corrections on vegetated scenes, three methods will be compared: regression, CIBR derivation and LOWTRAN 7. Field-measured bright and dark targets taken at the time of the 13 April, 1989 AVIRIS overflight of Jasper Ridge, California were used to formulate the regression method atmospheric correction. Using this corrected scene as 'ground truth', the CIBR derivation and the LOWTRAN 7 method with both input models are compared on the vegetated Jasper Ridge scene. Although representing a qualitative approach, this is a first approximation and shows the need for more quantitative analysis.

  18. Using Combined THEMIS Visible and Infrared Images to map Martian Topography and Slope- corrected Surface Thermal Properties

    NASA Astrophysics Data System (ADS)

    Cushing, G. E.; Titus, T. N.; Soderblom, L. A.; Kirk, R. L.

    2007-12-01

    Kirk et al. (2005) empirically deconvolved visible and thermal-infrared THEMIS data, isolating topographic information that produced an accurate digital-terrain model (DTM). Described here is the next step wherein we use the same dataset (Columbia Hills area, Mars) in conjunction with the KRC thermal model (Kieffer et al., 1977) to quantitatively derive and map slope-corrected thermophysical properties. Observed surface temperatures, at high spatial resolution, are a function of many variables such as: slope, albedo, thermal inertia, time, season and atmospheric opacity. We constrain each of these variables to construct a DTM and maps of slope-corrected albedo, slope/albedo-corrected thermal inertia, and surface temperatures across an entire scene for any time of day or year and any atmospheric opacity. DTMs greatly facilitate analyses of the Martian surface, but generating these data is a challenge. The MOLA global dataset does not have sufficient resolution (~3 km) to be combined with newer datasets (e.g. HiRISE, CTX, THEMIS, MOC, and CRISM), so new techniques to derive high-resolution DTMs are always being explored. Stereo imaging produces quality, high-resolution DTMs but is limited in the amount of available coverage. Photoclinometry techniques on visible-wavelength images have been widely investigated with varying degrees of success, but accounting for albedo variations across a scene has been an historical weakness of this method. Here we discuss a technique of combining THEMIS visible and thermal infrared (both daytime and nighttime) observations (Christensen et al., 2004) in such a manner that albedo variations in the scene are cancelled, allowing the production of a high-resolution DTM via photoclinometry techniques that are largely free of albedo-induced errors. We employ the KRC thermal-diffusion model to generate models of slope-corrected thermal properties from the resultant DTM and THEMIS observations. This technique can provide new perspectives and

  19. The Hubble Space Telescope: UV, Visible, and Near-Infrared Pursuits

    NASA Technical Reports Server (NTRS)

    Wiseman, Jennifer

    2010-01-01

    The Hubble Space Telescope continues to push the limits on world-class astrophysics. Cameras including the Advanced Camera for Surveys and the new panchromatic Wide Field Camera 3 which was installed nu last year's successful servicing mission S2N4,o{fer imaging from near-infrared through ultraviolet wavelengths. Spectroscopic studies of sources from black holes to exoplanet atmospheres are making great advances through the versatile use of STIS, the Space Telescope Imaging Spectrograph. The new Cosmic Origins Spectrograph, also installed last year, is the most sensitive UV spectrograph to fly io space and is uniquely suited to address particular scientific questions on galaxy halos, the intergalactic medium, and the cosmic web. With these outstanding capabilities on HST come complex needs for laboratory astrophysics support including atomic and line identification data. I will provide an overview of Hubble's current capabilities and the scientific programs and goals that particularly benefit from the studies of laboratory astrophysics.

  20. Dual optical frequency comb architecture with capabilities from visible to mid-infrared.

    PubMed

    Jerez, Borja; Martín-Mateos, Pedro; Prior, Estefanía; de Dios, Cristina; Acedo, Pablo

    2016-06-27

    In this paper, a new approach to dual comb generation based on well-known optical techniques (Gain-Switching and Optical Injection Locking) is presented. The architecture can be implemented using virtually every kind of continuous-wave semiconductor laser source (DFB, VCSEL, QCL) and without the necessity of electro-optic modulators. This way, a frequency-agile and adaptive dual-comb architecture is provided with potential implementation capabilities from mid-infrared to near ultraviolet. With a RF comb comprising around 70 teeth, the system is validated in the 1.5 μm region measuring the absorption feature of H13CN at 1538.523 nm with a minimum integration time of 10 μs.

  1. Analysis of Vegetation Within A Semi-Arid Urban Environment Using High Spatial Resolution Airborne Thermal Infrared Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Ridd, Merrill K.

    1998-01-01

    High spatial resolution (5 m) remote sensing data obtained using the airborne Thermal Infrared Multispectral Scanner (TIMS) sensor for daytime and nighttime have been used to measure thermal energy responses for 2 broad classes and 10 subclasses of vegetation typical of the Salt Lake City, Utah urban landscape. Polygons representing discrete areas corresponding to the 10 subclasses of vegetation types have been delineated from the remote sensing data and are used for analysis of upwelling thermal energy for day, night, and the change in response between day and night or flux, as measured by the TIMS. These data have been used to produce three-dimensional graphs of energy responses in W/ sq m for day, night, and flux, for each urban vegetation land cover as measured by each of the six channels of the TIMS sensor. Analysis of these graphs provides a unique perspective for both viewing and understanding thermal responses, as recorded by the TIMS, for selected vegetation types common to Salt Lake City. A descriptive interpretation is given for each of the day, night, and flux graphs along with an analysis of what the patterns mean in reference to the thermal properties of the vegetation types surveyed in this study. From analyses of these graphs, it is apparent that thermal responses for vegetation can be highly varied as a function of the biophysical properties of the vegetation itself, as well as other factors. Moreover, it is also seen where vegetation, particularly trees, has a significant influence on damping or mitigating the amount of thermal radiation upwelling into the atmosphere across the Salt Lake City urban landscape. Published by Elsevier Science Ltd.

  2. COMET 22P/KOPFF: DUST ENVIRONMENT AND GRAIN EJECTION ANISOTROPY FROM VISIBLE AND INFRARED OBSERVATIONS

    SciTech Connect

    Moreno, Fernando; Pozuelos, Francisco; Aceituno, Francisco; Casanova, Victor; Sota, Alfredo

    2012-06-20

    We present optical observations and Monte Carlo models of the dust coma, tail, and trail structures of the comet 22P/Kopff during the 2002 and 2009 apparitions. Dust loss rates, ejection velocities, and power-law size distribution functions are derived as functions of the heliocentric distance using pre- and post-perihelion imaging observations during both apparitions. The 2009 post-perihelion images can be accurately fitted by an isotropic ejection model. On the other hand, strong dust ejection anisotropies are required to fit the near-coma regions at large heliocentric distances (both inbound at r{sub h} = 2.5 AU and outbound at r{sub h} = 2.6 AU) for the 2002 apparition. These asymmetries are compatible with a scenario where dust ejection is mostly seasonally driven, coming mainly from regions near subsolar latitudes at far heliocentric distances inbound and outbound. At intermediate to near-perihelion heliocentric distances, the outgassing would affect much more extended latitude regions, the emission becoming almost isotropic near perihelion. We derived a maximum dust production rate of 260 kg s{sup -1} at perihelion, and an averaged production rate over one orbit of 40 kg s{sup -1}. An enhanced emission rate, also accompanied by a large ejection velocity, is predicted at r{sub h} > 2.5 pre-perihelion. The model has also been extended to the thermal infrared in order to be applied to available trail observations of this comet taken with IRAS and Infrared Space Observatory spacecrafts. The modeled trail intensities are in good agreement with those observations, which is remarkable taking into account that those data are sensitive to dust ejection patterns corresponding to several orbits before the 2002 and 2009 apparitions.

  3. Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared. Revision 1

    SciTech Connect

    Gavel, D.T.; Morris, J.R.; Vernon, R.G.

    1992-08-01

    We are building an adaptive-optic telescope system that is based on the use of an artificial guide star created by laser-induced fluorescence of the sodium mesospheric layer. This paper discusses the system design for mid-visible to near-infrared compensation of a one meter telescope at Livermore and near-infrared compensation of the ten meter Keck telescope at Mauna Kea. We calculate the expected Strehl ratio and resolution for a 69 channel deformable mirror system and also for a possible 24 channel system upgrade. With the 69 actuator system we expect near diffraction limited resolution, about 0.2 arcsec, with a Strehl ratio of about 0.5 at {gamma}=0.8 {mu}m on the 1m telescope, and resolution of about 0.05 arcsec with a Strehl ratio of about 0.5 at {gamma}=2.0 {mu}m on the 10m telescope. Resolution will be limited by the performance of the tip/tilt correction loop, which uses an off-axis natural guide star as a reference. At Livermore, our design uses an existing high power (1 kW) laser source, which is expected to provide an approximately 6th magnitude artificial guide star. This strong beacon signal allows a short integration time in the wavefront sensor so that temporal changes in the atmospheric turbulence can be tracked accurately. For Mauna Kea, we explore how the system to be built for the Livermore site would perform in the infrared, assuming a 100 W laser source.

  4. Mid-Infrared Pumped Laser-Induced Thermal Grating Spectroscopy for Detection of Acetylene in the Visible Spectral Range.

    PubMed

    Sahlberg, Anna-Lena; Kiefer, Johannes; Aldén, Marcus; Li, Zhongshan

    2016-06-01

    We present mid-infrared laser-induced thermal grating spectroscopy (IR-LITGS) using excitation radiation around 3 µm generated by a simple broadband optical parametric oscillator (OPO). Acetylene as a typical small hydrocarbon molecule is used as an example target species. A mid-infrared broadband OPO pumped by the fundamental output of a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser was used to generate the pump beams, with pulse energies of 6-10 mJ depending on the wavelength. The line width of the OPO idler beam was ∼5 cm(-1), which is large enough to cover up to six adjacent acetylene lines. The probe beam was the radiation of a 532 nm cw solid state laser with 190 mW output power. Signals were generated in atmospheric pressure gas flows of N2, air, CO2 and Ar with small admixtures of C2H2 A detection limit of less than 300 ppm was found for a point measurement of C2H2 diluted in N2 As expected, the oscillation frequency of the IR-LITGS signal was found to have a large dependency on the buffer gas, which allows determination of the speed of sound. Moreover, the results reveal a very strong collisional energy exchange between C2H2 and CO2 compared to the other gases. This manifests as significant local heating. In summary, the MIR-LITGS technique enables spectroscopy of fundamental vibrational transitions in the infrared via detection in the visible spectral range. PMID:27091904

  5. Soot scattering measurements in the visible and near-infrared spectrum

    SciTech Connect

    ZHU,JINYU; CHOI,MUN YOUNG; MULHOLLAND,GEORGE W.; GRITZO,LOUIS A.

    2000-02-08

    Scattering to extinction cross-section ratios, {rho}{sub se} were measured using the NIST Large Agglomerate Optics Facility for soot produced from ethene and acetylene laminar diffusion flames. Measurements were performed using light sources at 543.5 nm, 632.8 nm and 856 nm. The average scattering to extinction cross-section ratios for these wavelengths are equal to 0.246, 0.196, and 0.196 for ethene and 0.316, 0.230, and 0.239 for acetylene. The 856 nm measurements represent the longest wavelength for which accurate scattering measurements have been performed for soot. The size distribution and fractal properties of the two soots were determined to assess the effects of limited acceptance angle range, finite size of the sensor, and departure from cosine response on the uncertainty in the measurement of {rho}{sub se} The expanded relative uncertainty (95% confidence level) was found to be {+-}6% at the two visible wavelengths and {+-}8% at 856 nm. Both the magnitude and wavelength dependence of {rho}{sub se} for the present experiments are significantly different from those reported by Krishnan et al. for overfire soot produced using a turbulent flame. The results are compared with the predictions of fractal optics.

  6. Visible vs near-infrared optical fiber plasmonics: performance comparison for protein sensing

    NASA Astrophysics Data System (ADS)

    Caucheteur, Christophe; Ribaut, Clotilde; Wattiez, Ruddy

    2016-04-01

    In this work, two plasmonic optical fiber sensor configurations are used for protein sensing and their relative performances in terms of limit of detection and sensitivity are compared. The first configuration consists in unclad 200 μm optical fibers that produce a broadband resonance in the visible wavelength range around 650 nm while the second configuration makes use of multiple narrowband resonances produced in the C+L bands with weakly tilted fiber Bragg gratings photo-inscribed in telecommunication-grade single-mode optical fibers. In both cases, the sensitive regions are surrounded by a ~50 nm gold layer so that the evanescent wave can excite a surface plasmon polariton at the metalsurrounding medium interface. Both configurations are used to sense green fluorescent proteins. Our experimental results demonstrate that the two sensor configurations present a complementary measurement dynamics as a function of the investigated concentration in the range 10-12 - 10-7 g/ml. We attribute this difference of sensitivity to the difference of penetration depth of the evanescent wave in the surrounding medium, which is proportional to the light wavelength.

  7. [Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance].

    PubMed

    Zheng, Xiao-po; Sun, Yue-jun; Qin, Qi-ming; Ren, Hua-zhong; Gao, Zhong-ling; Wu, Ling; Meng, Qing-ye; Wang, Jin-liang; Wang, Jian-hua

    2015-08-01

    Soil is the loose solum of land surface that can support plants. It consists of minerals, organics, atmosphere, moisture, microbes, et al. Among its complex compositions, soil moisture varies greatly. Therefore, the fast and accurate inversion of soil moisture by using remote sensing is very crucial. In order to reduce the influence of soil type on the retrieval of soil moisture, this paper proposed a normalized spectral slope and absorption index named NSSAI to estimate soil moisture. The modeling of the new index contains several key steps: Firstly, soil samples with different moisture level were artificially prepared, and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company. Secondly, the moisture absorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after analyzing the regular spectral feature change patterns of different soil at different moisture conditions. Then advantages of the two features at reducing soil types' effects was synthesized to build the NSSAI. Thirdly, a linear relationship between NSSAI and soil moisture was established. The result showed that NSSAI worked better (correlation coefficient is 0.93) than most of other traditional methods in soil moisture extraction. It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy. PMID:26672277

  8. Nature of light scattering in dental enamel and dentin at visible and near-infrared wavelengths

    NASA Astrophysics Data System (ADS)

    Fried, Daniel; Glena, Richard E.; Featherstone, John D. B.; Seka, Wolf

    1995-03-01

    The light-scattering properties of dental enamel and dentin were measured at 543, 632, and 1053 nm. Angularly resolved scattering distributions for these materials were measured from 0 deg to 180 deg using a rotating goniometer. Surface scattering was minimized by immersing the samples in an index-matching bath. The scattering and absorption coefficients and the scattering phase function were deduced by comparing the measured scattering data with angularly resolved Monte Carlo light-scattering simulations. Enamel and dentin were best represented by a linear combination of a highly forward-peaked Henyey-Greenstein (HG) phase function and an isotropic phase function. Enamel weakly scatters light between 543 nm and 1.06 mu m, with the scattering coefficient ( mu s) ranging from mu s = 15 to 105 cm-1. The phase function is a combination of a HG function with g = 0.96 and a 30-60% isotropic phase function. For enamel, absorption is negligible. Dentin scatters strongly in the visible and near IR ( mu s approximately equals 260 cm-1) and absorbs weakly ( mu a approximately equals 4 cm-1). The scattering phase function for dentin is described by a HG function with g = 0.93 and a very weak isotropic scattering component ( approximately 2%).

  9. Alteration of hydrovolcanic basaltic ash - Observations with visible and near-infrared spectrometry

    NASA Technical Reports Server (NTRS)

    Farrand, William H.; Singer, Robert B.

    1992-01-01

    Altered basaltic tephras from tuff rings and tuff cones across the Basin and Range were examined using visible and NIR (Vis/IR) reflectance spectrometry and a variety of other techniques. It was found that Vis/IR spectrometry is sensitive to subtle changes in the hydration and oxidation state of these tephras. In the tuffs examined, ferrous and ferric iron minerals produce one composite absorption feature rather than two resolvable bands. Different styles of alteration were noted between thinly bedded tuff ring deposits emplaced by high energy, largely dry, pyroclastic surge and massively bedded tuff cone deposits emplaced by wetter, lower energy pyroclastic flow. The former class of tephras become hydrated and only moderately oxidized with some limited development of dioctehedral smectite clay minerals and minimal palagomitization. The latter class of tephras are highly palagonitized which implies a high degree of hydration and oxidation. In the most of highly altered tephras, all the Fe(2+) that is initially in the volcanic glass is converted to Fe(3+) within nanophase and bulk ferric oxide phases in the palagonite. There is also more extensive development in tuff cone beds of zeolite and phyllosilicate minerals. The differences in reflectance spectra of altered basaltic tephras can be traced to initial differences in the water/magma ratio extant at the volcanic vent.

  10. [Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance].

    PubMed

    Zheng, Xiao-po; Sun, Yue-jun; Qin, Qi-ming; Ren, Hua-zhong; Gao, Zhong-ling; Wu, Ling; Meng, Qing-ye; Wang, Jin-liang; Wang, Jian-hua

    2015-08-01

    Soil is the loose solum of land surface that can support plants. It consists of minerals, organics, atmosphere, moisture, microbes, et al. Among its complex compositions, soil moisture varies greatly. Therefore, the fast and accurate inversion of soil moisture by using remote sensing is very crucial. In order to reduce the influence of soil type on the retrieval of soil moisture, this paper proposed a normalized spectral slope and absorption index named NSSAI to estimate soil moisture. The modeling of the new index contains several key steps: Firstly, soil samples with different moisture level were artificially prepared, and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company. Secondly, the moisture absorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after analyzing the regular spectral feature change patterns of different soil at different moisture conditions. Then advantages of the two features at reducing soil types' effects was synthesized to build the NSSAI. Thirdly, a linear relationship between NSSAI and soil moisture was established. The result showed that NSSAI worked better (correlation coefficient is 0.93) than most of other traditional methods in soil moisture extraction. It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy.

  11. Toward consistent radiometric calibration of the NOAA AVHRR visible and near-infrared data record

    NASA Astrophysics Data System (ADS)

    Bhatt, Rajendra; Doelling, David R.; Scarino, Benjamin R.; Gopalan, Arun; Haney, Conor O.

    2015-09-01

    The 35-year Advanced Very High Resolution Radiometer (AVHRR) satellite-instrument data record is critical for studying decadal climate change, provided that the AVHRR sensors are consistently calibrated. Owing to the lack of onboard calibration capability, the AVHRR data need to be adjusted using vicarious approaches. One of the greatest challenges hampering these vicarious calibration techniques, however, is the degrading orbits of the NOAA satellites that house the instruments, or, more specifically, the fact that the satellites eventually drift into a terminator orbit several years after launch. This paper presents a uniform sensor calibration approach for the AVHRR visible (VIS) and nearinfrared (NIR) records using specifically designed NOAA-16 AVHRR-based, top-of-atmosphere (TOA) calibration models that take into account orbit degradation. These models are based on multiple invariant Earth targets, including Saharan deserts, polar ice scenes, and tropical deep-convective clouds. All invariant targets are referenced to the Aqua- MODIS Collection-6 calibration via transfer of the Aqua-MODIS calibration to NOAA-16 AVHRR using simultaneous nadir overpass (SNO) comparisons over the North Pole. A spectral band adjustment factor, based on SCanning Imaging Absorption SpectroMeter for Atmospheric CartograpHY (SCIAMACHY) spectral radiances, is used to account for the spectrally-induced biases caused by the spectral response function (SRF) differences of the AVHRR and MODIS sensors. Validation of the AVHRR Earth target calibration is performed by comparisons with contemporary MODIS SNOs. Calibration consistency between Earth targets validates the historical AVHRR record.

  12. Visible and Infrared Wavefront Sensing detectors review in Europe - part I

    NASA Astrophysics Data System (ADS)

    Feautrier, Philippe; Gach, Jean-luc

    2013-12-01

    The purpose of this review is to give an overview of the state of the art wavefront sensor detectors developments held in Europe for the last decade. A major breakthrough has been achieved with the development by e2v technologies of the CCD220 between 2004 and 2012. Another major breakthrough is currently achieved with the very successful development of fast low noise infrared arrays called RAPID. The astonishing results of this device will be showed for the first time in an international conference at AO4ELT3.The CCD220, a 240x240 pixels 8 outputs EMCCD (CCD with internal multiplication), offers less than 0.2 e readout noise at a frame rate of 1500 Hz with negligible dark current. The OCAM2 camera is the commercial product that drives this advanced device. This system, commercialized by First Light Imaging, is quickly described in this paper. An upgrade of OCAM2 is currently developed to boost its frame rate to 2 kHz, opening the window of XAO wavefront sensing for the ELT using 4 synchronized cameras and pyramid wavefront sensing. This upgrade and the results obtained are described extensively elsewhere in this conference (Gach et al).Since this major success, new detector developments started in Europe. The NGSD CMOS device is fully dedicated to Natural and Laser Guide Star AO for the E-ELT with ESO involvement. The spot elongation from a LGS Shack Hartman wavefront sensor necessitates an increase of the pixel format. The NGSD will be a 880x840 pixels CMOS detector with a readout noise of 3 e (goal 1e) at 700 Hz frame rate. New technologies will be developed for that purpose: advanced CMOS pixel architecture, CMOS back thinned and back illuminated device for very high QE, full digital outputs with signal digital conversion on chip. This innovative device will be used on the European ELT but also interests potentially all giant telescopes.Additional developments also started in 2009 for wavefront sensing in the infrared based on a new technological breakthrough

  13. Radiative transfer in water and ice clouds in the visible and infrared region.

    PubMed

    Plass, G N; Kattawar, G W

    1971-04-01

    The radiance and polarization are calculated at six wavelengths from 0.7 micro to 6.05 micro for the photons reflected from and transmitted through two model clouds representing water and ice clouds with modal radii of 12 micro and 50 micro, respectively. The single scattering matrix is obtained from the Mie theory for spherical particles from the measured values of the complex index of refraction for water and ice. Multiple scattering to all orders is taken into account by a Monte Carlo technique which computes the exact three-dimensional paths of the photons. The upward and downward radiance and polarization are given as a function of optical thickness for each cloud model. The mean optical path of the photon, the cloud albedo, and the flux at the lower and upper boundaries are also given. The reflected radiance is considerably less for the ice than for the nimbostatus (water) model at all angles at most infrared wavelengths, particularly at wavelengths of 1.7 micro, 2.1 micro, and 3.5 micro. The polarization of the reflected photons is often very much greater for the ice than for the nimbostratus model, particularly at wavelengths of 1.7 micro, 2.1 micro, and 3.5 micro. These differences may be used in order to discriminate between water and ice clouds from measurements of the reflected radiation.

  14. Two-color fluorescent (near-infrared and visible) triphasic perfluorocarbon nanoemulsions

    PubMed Central

    Patel, Sravan Kumar; Patrick, Michael J.; Pollock, John A.

    2013-01-01

    Abstract. Design and development of a new formulation as a unique assembly of distinct fluorescent reporters with nonoverlapping fluorescence spectra and a F19 magnetic resonance imaging agent into colloidally and optically stable triphasic nanoemulsion are reported. Specifically, a cyanine dye-perfluorocarbon (PFC) conjugate was introduced into the PFC phase of the nanoemulsion and a near-infrared dye was introduced into the hydrocarbon (HC) layer. To the best of our knowledge, this is the first report of a triphasic nanoemulsion system where each oil phase, HC, and PFC are fluorescently labeled and formulated into an optically and colloidally stable nanosystem. Having, each oil phase separately labeled by a fluorescent dye allows for improved correlation between in vivo imaging and histological data. Further, dual fluorescent labeling can improve intracellular tracking of the nanodroplets and help assess the fate of the nanoemulsion in biologically relevant media. The nanoemulsions were produced by high shear processing (microfluidization) and stabilized with biocompatible nonionic surfactants resulting in mono-modal size distribution with average droplet size less than 200 nm. Nanoemulsions demonstrate excellent colloidal stability and only moderate changes in the fluorescence signal for both dyes. Confocal fluorescence microscopy of macrophages exposed to nanoemulsions shows the presence of both fluorescence agents in the cytoplasm. PMID:23912666

  15. Automatic multispectral ultraviolet, visible and near-infrared capturing system for the study of artwork

    NASA Astrophysics Data System (ADS)

    Herrera, Jorge; Vilaseca, Meritxell; Pujol, Jaume

    2011-03-01

    This paper shows the simulations of the usage of a LED cluster as the illumination source for a multispectral imaging system covering the range of wavelengths from 350 to 1650 nm. The system can be described as being composed of two modules determined by the spectral range of the imaging sensors responses, one of them covering the range from 350- 950nm (CCD camera) and the other one covering the wavelengths from 900-1650nm (InGaAs camera). A well known method of reflectance estimation, the pseudo-inverse method, jointly with the experimentally measured data of the spectral responses of the cameras and the spectral emission of the LED elements are used for the simulations. The performance of the system for spectral estimation under ideal conditions and realistic noise influence is evaluated through different spectral and colorimetric metrics like the GFC, RMS error and CIEDE2000 color difference formula. The results show that is expectable a rather good performance of the real setup. However, they also reveal a difference in the performances of the modules. The second module has poorer performance due to the less narrow spectral emission and less number of LED elements that covers the near-infrared spectral range.

  16. A method for computing visible and infrared polarized monochromatic radiation in planetary atmospheres

    NASA Astrophysics Data System (ADS)

    Wauben, W. M. F.; de Haan, J. F.; Hovenier, J. W.

    1994-02-01

    In this paper we present a computational method, based on the so-called adding principle, for calculating the polarized monochromatic radiation in plane-parallel vertically inhomogeneous atmospheres. Our computer code is verified by comparing numerical results with those obtained by other investigators using different methods. We consider not only the well-known case of illumination by a unidirectional beam of light at the top of the atmosphere, but also illumination by isotropically radiating internal sources and illumination by an isotropically radiating ground surface below the atmosphere. Numerical results for all relevant Stokes parameters are tabulated for a two-layer atmosphere containing molecules and haze particles. These results pertain to the three types of illumination mentioned above. Furthermore, we describe some general features of polarized radiation in an optically thick homogeneous atmosphere containing cloud C1 water droplets. It is shown that multiple scattering of radiation in such a cloudy atmosphere may not be ignored at infrared wavelengths if molecular absorption is negligible.

  17. Visible and infrared emission from GaN:Er thin films grown by sputtering

    SciTech Connect

    Chen, H.; Gurumurugan, K.; Kordesch, M.E.; Jadwisienczak, W.M.; Lozykowski, H.J.

    2000-07-01

    Erbium-doped films were grown on sapphire and silicon substrates by reactive sputtering, with different Er concentrations in the film. GaN films deposited at 800 K were determined to be polycrystalline by x-ray diffraction analysis, and retained their polycrystalline structure after annealing in nitrogen at 1,250 K. The Er-doped films showed optical transmission beginning at about 360 nm, and the Er dose and film purity were determined with Rutherford backscattering spectroscopy. Photoluminescence and cathodoluminescence spectroscopy showed sharp emission lines corresponding to Er{sup 3+} intra 4f{sup n} shell transitions over the range from 9--300 K. At above-bandgap optical and electron excitation, the {sup 4}S{sub 3/2} and {sup 4}F{sub 9/2} transition dominate, and are superposed on the yellow band emission. The infrared emission line at 1,543 nm, corresponding to the Er {sup 4}I{sub 13/2} to {sup 4}I{sub 5/2} transition is also observed.

  18. Optical fabrication and metrology for a visible through thermal infrared multi-band imaging system

    SciTech Connect

    Magner, J.; Henson, T.

    1998-04-01

    The optical fabrication, metrology, and system wavefront testing of an off-axis three mirror anastigmatic telescope will be presented. The telescope is part of a multi-band imaging system which includes a single mechanically cooled focal plane with 15 spectral bands covering a wavelength range from 0.45 microns to 10.7 microns and an on board calibration subsystem. The imaging system is to be operated in a low earth orbit in a pushbroom scanning mode. The telescope has a 36 cm aperture, a 1.38 degree cross track by 1.82 degree along-track field of view (FOV), near diffraction limited performance in the visible, and strictly diffraction limited performance from 1.3 microns to 10.7 microns. The primary and the tertiary mirrors are general aspheres which have undergone 80% lightweighting. The secondary mirror is a hyperbola. The primary mirror was extremely difficult to fabricate and test due to its large departure from sphericity, fast f-number, and large off axis distance. The tertiary mirror has a small departure from sphericity and is only slightly off-axis, but it has a very fast f-number also. The surface wavefront measurements for the three mirrors after final figuring and lightweighting are 0.048 waves rms {at}0.6328 microns for the primary mirror and 0.025 waves rms {at}0.6328 microns for the secondary and tertiary mirrors. The telescope wavefront requirement at the center of the along-track FOV is 0.178 waves rms {at}0.6328 microns and at the edge of the along-track FOV is 0.677 waves rms {at} 0.6328 microns.

  19. Measurement of moisture, soluble solids, and sucrose content and mechanical properties in sugar beet using portable visible and near-infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visible and near-infrared spectroscopy, coupled with partial least squares regression, was used to predict the moisture, soluble solids and sucrose content and mechanical properties of sugar beet. Interactance spectra were acquired from both intact and sliced beets, using two portable spectrometers ...

  20. Visible and near-infrared reflectance spectroscopy of planetary analog materials. Experimental facility at Laboratoire de Planetologie de Grenoble.

    NASA Astrophysics Data System (ADS)

    Pommerol, A.; Brissaud, O.; Schmitt, B.; Quirico, E.; Doute, S.

    2007-08-01

    We have developed an original experimental facility designed to measure the bidirectional reflectance spectra of planetary analog materials. These measurements are helpful to interpret the observations of the spectrometers on board space probes in orbit around various Solar System bodies. The central part of the facility is the LPG spectrogonio- radiometer (Brissaud et al., 2004). This instrument provides measurements of samples BRDF (Bidirectional Reflectance Distribution Function) with high photometric and spectrometric accuracy in the spectral range of visible and near-infrared (0.3 - 4.8 microns). Measurements can be made at any value of incidence and emergence angle up to 80°. Azimuth angle is allowed to vary between 0 and 180°. The instrument was recently installed in a cold room allowing ambient temperatures as low as -20°C. This makes possible the measurements on different kinds of water ice samples (slab ice, frost, snow...) and mixtures of minerals and water ice with unprecedented accuracy. We also have designed and built a simulation chamber to measure spectra of samples (water ice and/or minerals) under an atmosphere with perfectly controlled temperature, pressure and composition. The main objective of this last improvement is the study of water exchange between planetary regolith analogs and atmosphere (adsorption/ desorption, condensation/sublimation). Experimental results will mainly apply to Martian water cycle and hydrated mineralogy. This simulation chamber also provides an efficient way to obtain bidirectional reflectance spectra of dry materials (removal of adsorbed water) with implications for planetary bodies without atmospheric or surface water (Titan, asteroids...). The reflectance spectroscopy facility is part of a large panel of instruments and techniques available at Laboratoire de Planetologie de Grenoble that provide complementary measurements on the same samples: infrared transmission spectroscopy of thin ice films, thick liquid and

  1. Influence of pre-existing topography on downflow lava discharge rates estimated from thermal infrared airborne data

    NASA Astrophysics Data System (ADS)

    Lombardo, V.

    2016-04-01

    Remote sensing thermal data of active lava flows allow the evaluation of effusion rates. This is made possible by a simple formula relating the lava effusion rate to the heat flux radiated per unit time from the surface of the flow. Due to the assumptions of the model, this formula implies that heat flux, surface temperature and lava temperature vary as a function of the flow thickness. These relationships, never verified or validated before, have been used by several authors as a proof of the weakness of the model. Here, multispectral infrared and visible imaging spectrometer (MIVIS) high spatial resolution (5-10 m) thermal data acquired during Etna's 2001 eruption were used to investigate downflow heat flux variations in the lava flow emitted from a vent located at 2100 m a.s.l. A high correlation between the downflow heat flux and the lava flow thickness (measured from a pre-existing digital elevation model) was found. Topography beneath the flow appears to play an important role both in lava emplacement mechanisms and flow dynamics. MIVIS-derived downflow effusion rates are consistent with the law of conservation of mass assessing the reliability of remote sensing techniques.

  2. Ten new predicted covalent organic frameworks with strong optical response in the visible and near infrared

    NASA Astrophysics Data System (ADS)

    Yang, Li-Ming; Dornfeld, Matthew; Hui, Pik-Mai; Frauenheim, Thomas; Ganz, Eric

    2015-06-01

    We use density functional theory to predict and evaluate 10 novel covalent organic frameworks (COFs), labeled (X4Y)(BDC)3, (X = C/Si; Y = C, Si, Ge, Sn, and Pb), with topology based on metal organic framework isoreticular metal-organic framework (IRMOF-1), but with new elements substituted for the corner atoms. We show that these new materials are stable structures using frequency calculations. For two structures, (C4C and Si4C) molecular dynamics simulations were performed to demonstrate stability of the systems up to 600 K for 10 ps. This demonstrates the remarkable stability of these systems, some of which may be experimentally accessible. For the C4C material, we also explored the stability of isolated corners and linkers and vacuum and started to build the structure from these pieces. We discuss the equilibrium lattice parameters, formation enthalpies, electronic structures, chemical bonding, and mechanical and optical properties. The predicted bulk moduli of these COFs range from 18.9 to 23.9 GPa, larger than that of IRMOF-1 (ca. 15.4 GPa), and larger than many existing 3D COF materials. The band gaps range from 1.5 to 2.1 eV, corresponding to 600-830 nm wavelength (orange through near infrared). The negative values of the formation enthalpy suggest that they are stable and should be experimentally accessible under suitable conditions. Seven materials distort the crystal structure to a lower space group symmetry Fm-3, while three materials maintain the original Fm-3m space group symmetry. All of the new materials are highly luminescent. We hope that this work will inspire efforts for experimental synthesis of these new materials.

  3. Ten new predicted covalent organic frameworks with strong optical response in the visible and near infrared.

    PubMed

    Yang, Li-Ming; Dornfeld, Matthew; Hui, Pik-Mai; Frauenheim, Thomas; Ganz, Eric

    2015-06-28

    We use density functional theory to predict and evaluate 10 novel covalent organic frameworks (COFs), labeled (X4Y)(BDC)3, (X = C/Si; Y = C, Si, Ge, Sn, and Pb), with topology based on metal organic framework isoreticular metal-organic framework (IRMOF-1), but with new elements substituted for the corner atoms. We show that these new materials are stable structures using frequency calculations. For two structures, (C4C and Si4C) molecular dynamics simulations were performed to demonstrate stability of the systems up to 600 K for 10 ps. This demonstrates the remarkable stability of these systems, some of which may be experimentally accessible. For the C4C material, we also explored the stability of isolated corners and linkers and vacuum and started to build the structure from these pieces. We discuss the equilibrium lattice parameters, formation enthalpies, electronic structures, chemical bonding, and mechanical and optical properties. The predicted bulk moduli of these COFs range from 18.9 to 23.9 GPa, larger than that of IRMOF-1 (ca. 15.4 GPa), and larger than many existing 3D COF materials. The band gaps range from 1.5 to 2.1 eV, corresponding to 600-830 nm wavelength (orange through near infrared). The negative values of the formation enthalpy suggest that they are stable and should be experimentally accessible under suitable conditions. Seven materials distort the crystal structure to a lower space group symmetry Fm-3, while three materials maintain the original Fm-3m space group symmetry. All of the new materials are highly luminescent. We hope that this work will inspire efforts for experimental synthesis of these new materials.

  4. The structure of the planetary nebula NGC 2371 in the visible and mid-infrared

    NASA Astrophysics Data System (ADS)

    Ramos-Larios, Gerardo; Phillips, J. P.

    2012-09-01

    We investigate the structure of the planetary nebula NGC 2371 using [O III] λ5007 imaging taken with the Jacobus Kapteyn 1.0 m telescope, and [N II] λ6584, [O III] λ5007 and Hα results acquired with the Hubble Space Telescope. These are supplemented with archival mid-infrared (MIR) observations taken with the Spitzer Space Telescope. We note the presence of off-axis low-ionization spokes along a position angle of 65°, and associated collars of enhanced [O III] emission. The spokes appear to consist of dense condensations having low-excitation tails, possibly arising due to ultraviolet shadowing and/or ram-pressure stripping of material. Line ratios imply that most of the emission arises through photoionization, and is unlikely to derive from post-shock cooling regions. An analysis of these features in the MIR suggests that they may also be associated with high levels of emission from polycyclic aromatic hydrocarbons (PAHs), together with various permitted and forbidden line transitions. Such high levels of PAH emission, where they are confirmed, may develop as a result of preferentially enhanced far-ultraviolet pumping of the molecules, or shattering of larger grains within local shocks. Although H2 emission may also contribute to these trends, it is argued that shock-excited transitions would lead to markedly differing results. We finally note that thin filaments and ridges of [O III] emission may indicate the presence of shock activity at the limits of the interior envelope, as well as at various positions within the shell itself. We also note that radially increasing fluxes at 3.6, 5.8 and 8.0 μm, relative to the emission at 4.5 μm, may arise due to enhanced PAH emission in external photodissociative regions.

  5. Fire detection and monitoring using MSG Spinning Enhanced Visible and Infrared Imager (SEVIRI) data

    NASA Astrophysics Data System (ADS)

    Calle, A.; Casanova, J. L.; Romo, A.

    2006-12-01

    Detection and parameterization of forest fires is a task traditionally performed by polar-orbiting sensors, mainly advanced very high resolution radiometer (AVHRR) advanced along track scanning radiometer (AATSR), bispectral infrared detection (BIRD), and Moderate Resolution Imaging Spectroradiometer (MODIS). However, their time resolution is a problem to operate in real time. New geostationary sensors have proven their capacity for Earth observation. GOES, MSG, and MTSAT are already operative with time resolutions below 30 min. The international community feels that a real-time global observation network may become a reality, which is the aim of the Global Observations of Forest Cover and Land Cover Dynamics (GOFC/GOLD) FIRE Mapping and Monitoring program, focusing internationally on decision-making concerning research into global change. This paper shows the operation in real time by the MSG SEVIRI sensor over the Iberian Peninsula. For fire detection, a temporal gradient of temperature 3.9 μm is used, which is more efficient at eliminating incoming false alarms from solar reflection. Capacity to detect hot forest fires below 0.3 ha in Mediterranean latitudes has been analyzed along with the conditions in which it is possible to apply the MODIS methodology to establish the fire radiative energy (FRE) by means of experimental relation. We found that in this case, fire size can introduce maximum differences of 40% in FRE for small-scale fires. The capacity of this sensor is shown in different cases that have greatly impacted Spain and Portugal because of the loss of human life.

  6. Ten new predicted covalent organic frameworks with strong optical response in the visible and near infrared

    SciTech Connect

    Yang, Li-Ming E-mail: ganzx001@umn.edu; Frauenheim, Thomas; Dornfeld, Matthew; Hui, Pik-Mai; Ganz, Eric E-mail: ganzx001@umn.edu

    2015-06-28

    We use density functional theory to predict and evaluate 10 novel covalent organic frameworks (COFs), labeled (X{sub 4}Y)(BDC){sub 3}, (X = C/Si; Y = C, Si, Ge, Sn, and Pb), with topology based on metal organic framework isoreticular metal-organic framework (IRMOF-1), but with new elements substituted for the corner atoms. We show that these new materials are stable structures using frequency calculations. For two structures, (C{sub 4}C and Si{sub 4}C) molecular dynamics simulations were performed to demonstrate stability of the systems up to 600 K for 10 ps. This demonstrates the remarkable stability of these systems, some of which may be experimentally accessible. For the C{sub 4}C material, we also explored the stability of isolated corners and linkers and vacuum and started to build the structure from these pieces. We discuss the equilibrium lattice parameters, formation enthalpies, electronic structures, chemical bonding, and mechanical and optical properties. The predicted bulk moduli of these COFs range from 18.9 to 23.9 GPa, larger than that of IRMOF-1 (ca. 15.4 GPa), and larger than many existing 3D COF materials. The band gaps range from 1.5 to 2.1 eV, corresponding to 600–830 nm wavelength (orange through near infrared). The negative values of the formation enthalpy suggest that they are stable and should be experimentally accessible under suitable conditions. Seven materials distort the crystal structure to a lower space group symmetry Fm-3, while three materials maintain the original Fm-3m space group symmetry. All of the new materials are highly luminescent. We hope that this work will inspire efforts for experimental synthesis of these new materials.

  7. Visible up-conversion and near-infrared luminescence of Er3+/Yb3+ co-doped SbPO4-GeO2 glasses

    NASA Astrophysics Data System (ADS)

    Manzani, D.; Montesso, M.; Mathias, C. F.; Krishanaiah, K. Venkata; Ribeiro, S. J. L.; Nalin, M.

    2016-07-01

    Recent advances in glass chemistry have led to new multifunctional optical glasses of great technological importance. Glasses containing high amounts of antimony have been studied for use in nonlinear optics, near-infrared transmission, and as hosts for rare-earth ions in photonic devices. This work describes a luminescence study of Er3+ and Er3+/Yb3+ co-doping in a new SbPO4-GeO2 binary glass system. Near-infrared and visible up-conversion emissions were observed in the green and red regions, which are enhanced when the samples are co-doped with Yb3+. Near-infrared emissions have good quantum efficiency and full width half maximum of 61 nm. Visible up-conversion emissions are governed by two photons and described by excited state absorption, energy transfer and cross-relaxation processes.

  8. A Cryogenic, Insulating Suspension System for the High Resolution Airborne Wideband Camera (HAWC)and Submillemeter And Far Infrared Experiment (SAFIRE) Adiabatic Demagnetization Refrigerators (ADRs)

    NASA Technical Reports Server (NTRS)

    Voellmer, George M.; Jackson, Michael L.; Shirron, Peter J.; Tuttle, James G.

    2002-01-01

    The High Resolution Airborne Wideband Camera (HAWC) and the Submillimeter And Far Infrared Experiment (SAFIRE) will use identical Adiabatic Demagnetization Refrigerators (ADR) to cool their detectors to 200mK and 100mK, respectively. In order to minimize thermal loads on the salt pill, a Kevlar suspension system is used to hold it in place. An innovative, kinematic suspension system is presented. The suspension system is unique in that it consists of two parts that can be assembled and tensioned offline, and later bolted onto the salt pill.

  9. Dispersion properties and low infrared optical losses in epitaxial AlN on sapphire substrate in the visible and infrared range

    SciTech Connect

    Soltani, A. Stolz, A.; Gerbedoen, J.-C.; Rousseau, M.; Bourzgui, N.; De Jaeger, J.-C.; Charrier, J.; Mattalah, M.; Barkad, H. A.; Mortet, V.

    2014-04-28

    Optical waveguiding properties of a thick wurtzite aluminum nitride highly [002]-textured hetero-epitaxial film on (001) basal plane of sapphire substrate are studied. The physical properties of the film are determined by X-ray diffraction, atomic force microscopy, microRaman, and photocurrent spectroscopy. The refractive index and the thermo-optic coefficients are determined by m-lines spectroscopy using the classical prism coupling technique. The optical losses of this planar waveguide are also measured in the spectral range of 450–1553 nm. The lower value of optical losses is equal to 0.7 dB/cm at 1553 nm. The optical losses due to the surface scattering are simulated showing that the contribution is the most significant at near infrared wavelength range, whereas the optical losses are due to volume scattering and material absorption in the visible range. The good physical properties and the low optical losses obtained from this planar waveguide are encouraging to achieve a wide bandgap optical guiding platform from these aluminum nitride thin films.

  10. An airborne infrared laser spectrometer for in-situ trace gas measurements: application to tropical convection case studies

    NASA Astrophysics Data System (ADS)

    Catoire, V.; Krysztofiak, G.; Robert, C.; Chartier, M.; Jacquet, P.; Guimbaud, C.; Hamer, P. D.; Marécal, V.

    2015-09-01

    A three-channel laser absorption spectrometer called SPIRIT (SPectromètre InfraRouge In situ Toute altitude) has been developed for airborne measurements of trace gases in the troposphere and lower stratosphere. More than three different species can be measured simultaneously with high time resolution (each 1.6 s) using three individual CW-DFB-QCLs (Continuous Wave Distributed FeedBack Quantum Cascade Lasers) coupled to a single Robert multipass optical cell. The lasers are operated in a time-multiplexed mode. Absorption of the mid-infrared radiations occur in the cell (2.8 L with effective path lengths of 134 to 151 m) at reduced pressure, with detection achieved using a HgCdTe detector cooled by Stirling cycle. The performances of the instrument are described, in particular precisions of 1, 1 and 3 %, and volume mixing ratio (vmr) sensitivities of 0.4, 6 and 2.4 ppbv are determined at 1.6 s for CO, CH4 and N2O, respectively (at 1σ confidence level). Estimated accuracies without calibration are about 6 %. Dynamic measuring ranges of about four decades are established. The first deployment of SPIRIT was realized aboard the Falcon-20 research aircraft operated by DLR (Deutsches Zentrum für Luft- und Raumfahrt) within the frame of the SHIVA (Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere) European project in November-December 2011 over Malaysia. The convective outflows from two large convective systems near Borneo Island (6.0° N-115.5° E and 5.5° N-118.5° E) were sampled above 11 km in altitude on 19 November and 9 December, respectively. Correlated enhancements in CO and CH4 vmr were detected when the aircraft crossed the outflow anvil of both systems. These enhancements were interpreted as the fingerprint of transport from the boundary layer up through the convective system and then horizontal advection in the outflow. Using these observations, the fraction of boundary layer air contained in fresh convective outflow was calculated to range

  11. Applications of airborne remote sensing in atmospheric sciences research

    NASA Technical Reports Server (NTRS)

    Serafin, R. J.; Szejwach, G.; Phillips, B. B.

    1984-01-01

    This paper explores the potential for airborne remote sensing for atmospheric sciences research. Passive and active techniques from the microwave to visible bands are discussed. It is concluded that technology has progressed sufficiently in several areas that the time is right to develop and operate new remote sensing instruments for use by the community of atmospheric scientists as general purpose tools. Promising candidates include Doppler radar and lidar, infrared short range radiometry, and microwave radiometry.

  12. Geographic classification of spanish and Australian tempranillo red wines by visible and near-infrared spectroscopy combined with multivariate analysis.

    PubMed

    Liu, L; Cozzolino, D; Cynkar, W U; Gishen, M; Colby, C B

    2006-09-01

    Visible (vis) and near-infrared (NIR) spectroscopy combined with multivariate analysis was used to classify the geographical origin of commercial Tempranillo wines from Australia and Spain. Wines (n = 63) were scanned in the vis and NIR regions (400-2500 nm) in a monochromator instrument in transmission. Principal component analysis (PCA), discriminant partial least-squares discriminant analysis (PLS-DA) and linear discriminant analysis (LDA) based on PCA scores were used to classify Tempranillo wines according to their geographical origin. Full cross-validation (leave-one-out) was used as validation method when PCA and LDA classification models were developed. PLS-DA models correctly classified 100% and 84.7% of the Australian and Spanish Tempranillo wine samples, respectively. LDA calibration models correctly classified 72% of the Australian wines and 85% of the Spanish wines. These results demonstrate the potential use of vis and NIR spectroscopy, combined with chemometrics as a rapid method to classify Tempranillo wines accordingly to their geographical origin.

  13. Application of Visible and Near-Infrared Hyperspectral Imaging to Determine Soluble Protein Content in Oilseed Rape Leaves.

    PubMed

    Zhang, Chu; Liu, Fei; Kong, Wenwen; He, Yong

    2015-01-01

    Visible and near-infrared hyperspectral imaging covering spectral range of 380-1030 nm as a rapid and non-destructive method was applied to estimate the soluble protein content of oilseed rape leaves. Average spectrum (500-900 nm) of the region of interest (ROI) of each sample was extracted, and four samples out of 128 samples were defined as outliers by Monte Carlo-partial least squares (MCPLS). Partial least squares (PLS) model using full spectra obtained dependable performance with the correlation coefficient (r(p)) of 0.9441, root mean square error of prediction (RMSEP) of 0.1658 mg/g and residual prediction deviation (RPD) of 2.98. The weighted regression coefficient (Bw), successive projections algorithm (SPA) and genetic algorithm-partial least squares (GAPLS) selected 18, 15, and 16 sensitive wavelengths, respectively. SPA-PLS model obtained the best performance with r(p) of 0.9554, RMSEP of 0.1538 mg/g and RPD of 3.25. Distribution of protein content within the rape leaves were visualized and mapped on the basis of the SPA-PLS model. The overall results indicated that hyperspectral imaging could be used to determine and visualize the soluble protein content of rape leaves. PMID:26184198

  14. Visible and near-infrared light transmission: A hybrid imaging method for non-destructive meat quality evaluation

    NASA Astrophysics Data System (ADS)

    Ziadi, A.; Maldague, X.; Saucier, L.; Duchesne, C.; Gosselin, R.

    2012-09-01

    Visual inspection of the amount of external marbling (intramuscular fat) on the meat surface is the official method used to assign the quality grading level of meat. However, this method is based exclusively on the analysis of the meat surface without any information about the internal content of the meat sample. In this paper, a new method using visible (VIS) and near-infrared (NIR) light transmission is used to evaluate the quality of beef meat based on the marbling detection. It is demonstrated that using NIR light in transmission mode, it is possible to detect the fat not only on the surface, as in traditional methods, but also under the surface. Moreover, in combining the analysis of the two sides of the meat simple, it is possible to estimate the volumetric marbling which is not accessible by visual methods commonly proposed in computer vision. To the best of our knowledge, no similar work or method has been published or developed. The experimental results confirm the expected properties of the proposed method and illustrate the quality of the results obtained.

  15. Mapping hydrothermal alteration using aircraft VNIR scanners at the Rosemont porphyry copper deposit. [Visible-Near Infrared

    NASA Technical Reports Server (NTRS)

    Sadowski, R. M.; Abrams, M. J.

    1983-01-01

    Two Visible-Near Infrared (VNIR) scanners, the NS-001 and the M2S, were flown over the Rosemont porphyry copper deposit as part of the NASA/JPL/GEOSAT test site program. This program was established to determine the feasibility and limitations of mapping hydrothermal alteration with multispectral scanners. Data from the NS-001 at 0.83 and 2.2 microns were used to identify Fe(3+) and OH enriched outcrops. These areas were then correlated with three alteration assemblages. The first correlation, hematite-epidote, was the most obvious and appeared as a strong ferric iron signature associated with hematite stained Cretaceous arkoses and andesites. The second correlation, qtz-sericite, showed a combined ferric-hydroxyl signature for a phyllicly altered quartz monzonite. The third correlation, skarn, was identified only after a review of calc-silicate mineral VNIR spectra. Altered limestones that outcrop west of the deposit have a similar ferric iron-hydroxyl signature as the quartz-sericite altered quartz monzonite. This skarn signature has been interpreted to indicate the presence of andradite, hydro-grossularite and idocrase. Data from the second scanner, M2S, was used to search for variation in ferric iron mineral type. Resulting imagery data indicated that hematite was the dominant ferric iron mineral present in the Rosemont area.

  16. Visible and near-infrared multispectral analysis of rocks at Meridiani Planum, Mars, by the Mars Exploration Rover Opportunity

    USGS Publications Warehouse

    Farrand, W. H.; Bell, J.F.; Johnson, J. R.; Jolliff, B.L.; Knoll, A.H.; McLennan, S.M.; Squyres, S. W.; Calvin, W.M.; Grotzinger, J.P.; Morris, R.V.; Soderblom, J.; Thompson, S.D.; Watters, W.A.; Yen, A. S.

    2007-01-01

    Multispectral measurements in the visible and near infrared of rocks at Meridiani Planum by the Mars Exploration Rover Opportunity's Pancam are described. The Pancam multispectral data show that the outcrops of the Burns formation consist of two main spectral units which in stretched 673, 535, 432 nm color composites appear buff- and purple-colored. These units are referred to as the HFS and LFS spectral units based on higher and lower values of 482 to 535 nm slope. Spectral characteristics are consistent with the LFS outcrop consisting of less oxidized, and the HFS outcrop consisting of more oxidized, iron-bearing minerals. The LFS surfaces are not as common and appear, primarily, at the distal ends of outcrop layers and on steep, more massive surfaces, locations that are subject to greater eolian erosion. Consequently, the HFS surfaces are interpreted as a weathering rind. Further inherent spectral differences between layer's and between different outcrop map units, both untouched and patches abraded by the rover's Rock Abrasion Tool, are also described. Comparisons of the spectral parameters of the Meridiani outcrop with a set of laboratory reflectance measurements of Fe3+-bearing minerals show that the field of outcrop measurements plots near the fields of hematite, ferrihydrite, poorly crystalline goethite, and schwertmannite. Rind and fracture fill materials, observed intermittently at outcrop exposures, are intermediate in their spectral character between both the HFS and LFS spectral classes and other, less oxidized, surface materials (basaltic sands, spherules, and cobbles). Copyright 2007 by the American Geophysical Union.

  17. SeaWiFS Technical Report Series. Volume 7: Cloud screening for polar orbiting visible and infrared (IR) satellite sensors

    NASA Technical Reports Server (NTRS)

    Darzi, Michael; Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor)

    1992-01-01

    Methods for detecting and screening cloud contamination from satellite derived visible and infrared data are reviewed in this document. The methods are applicable to past, present, and future polar orbiting satellite radiometers. Such instruments include the Coastal Zone Color Scanner (CZCS), operational from 1978 through 1986; the Advanced Very High Resolution Radiometer (AVHRR); the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), scheduled for launch in August 1993; and the Moderate Resolution Imaging Spectrometer (IMODIS). Constant threshold methods are the least demanding computationally, and often provide adequate results. An improvement to these methods are the least demanding computationally, and often provide adequate results. An improvement to these methods is to determine the thresholds dynamically by adjusting them according to the areal and temporal distributions of the surrounding pixels. Spatial coherence methods set thresholds based on the expected spatial variability of the data. Other statistically derived methods and various combinations of basic methods are also reviewed. The complexity of the methods is ultimately limited by the computing resources. Finally, some criteria for evaluating cloud screening methods are discussed.

  18. Application of Visible and Near-Infrared Hyperspectral Imaging to Determine Soluble Protein Content in Oilseed Rape Leaves

    PubMed Central

    Zhang, Chu; Liu, Fei; Kong, Wenwen; He, Yong

    2015-01-01

    Visible and near-infrared hyperspectral imaging covering spectral range of 380–1030 nm as a rapid and non-destructive method was applied to estimate the soluble protein content of oilseed rape leaves. Average spectrum (500–900 nm) of the region of interest (ROI) of each sample was extracted, and four samples out of 128 samples were defined as outliers by Monte Carlo-partial least squares (MCPLS). Partial least squares (PLS) model using full spectra obtained dependable performance with the correlation coefficient (rp) of 0.9441, root mean square error of prediction (RMSEP) of 0.1658 mg/g and residual prediction deviation (RPD) of 2.98. The weighted regression coefficient (Bw), successive projections algorithm (SPA) and genetic algorithm-partial least squares (GAPLS) selected 18, 15, and 16 sensitive wavelengths, respectively. SPA-PLS model obtained the best performance with rp of 0.9554, RMSEP of 0.1538 mg/g and RPD of 3.25. Distribution of protein content within the rape leaves were visualized and mapped on the basis of the SPA-PLS model. The overall results indicated that hyperspectral imaging could be used to determine and visualize the soluble protein content of rape leaves. PMID:26184198

  19. Determination of citric acid of lemon vinegar using visible/near infrared spectroscopy and least squares-support vector machine

    NASA Astrophysics Data System (ADS)

    Liu, Fei; Wang, Li; He, Yong

    2008-11-01

    The determination of citric acid of lemon vinegar was processed using visible and near infrared (Vis/NIR) spectroscopy combined with least squares-support vector machine (LS-SVM). Five concentration levels (100%, 80%, 60%, 40% and 20%) of lemon vinegar were studied. The calibration set was consisted of 225 samples (45 samples for each level) and the remaining 75 samples for the validation set. Partial least squares (PLS) analysis was employed for the calibration models as well as extraction of certain latent variables (LVs) and effective wavelengths (EWs). Different preprocessing methods were compared in PLS models including smoothing, standard normal variate (SNV), the first and second derivative. The selected LVs and EWs were employed as the inputs to develop least square-support vector machine (LSSVM) models. The optimal prediction results were achieved by LV-LS-SVM model, and the correlation coefficient (r), root mean square error of prediction (RMSEP) and bias for validation set were 0.9990, 0.1972 and -0.0334, respectively. Moreover, the EW-LS-SVM model was also acceptable and slightly better than all PLS models. The results indicated that Vis/NIR spectroscopy could be utilized as a parsimonious and efficient way for the determination of citric acid of lemon vinegar based on LS-SVM method.

  20. FPGA-based data processing module design of on-board radiometric calibration in visible/near infrared bands

    NASA Astrophysics Data System (ADS)

    Zhou, Guoqing; Li, Chenyang; Yue, Tao; Liu, Na; Jiang, Linjun; Sun, Yue; Li, Mingyan

    2015-12-01

    FPGA technology has long been applied to on-board radiometric calibration data processing however the integration of FPGA program is not good enough. For example, some sensors compressed remote sensing images and transferred to ground station to calculate the calibration coefficients. It will affect the timeliness of on-board radiometric calibration. This paper designs an integrated flow chart of on-board radiometric calibration. Building FPGA-based radiometric calibration data processing modules uses system generator. Thesis focuses on analyzing the calculation accuracy of FPGA-based two-point method and verifies the feasibility of this method. Calibration data was acquired by hardware platform which was built using integrating sphere, CMOS camera (canon 60d), ASD spectrometers and light filter (center wavelength: 690nm, bandwidth: 45nm). The platform can simulate single-band on-board radiometric calibration data acquisition in visible/near infrared band. Making an experiment of calibration coefficients calculation uses obtained data and FPGA modules. Experimental results show that: the camera linearity is above 99% meeting the experimental requirement. Compares with MATLAB the calculation accuracy of two-point method by FPGA are as follows: the error of gain value is 0.0053%; the error of offset value is 0.00038719%. Those results meet experimental accuracy requirement.

  1. Far-infrared through visible optical characterization of polymer-based electrochromic devices on single-walled carbon nanotube electrodes

    NASA Astrophysics Data System (ADS)

    Nasrollahi, Zahra; Vasilyeva, Svetlana V.; Donoghue, Evan P.; Rinzler, Andrew G.; Tanner, D. B.

    2012-02-01

    Electrochromic polymers (ECPs) exhibit reversible optical modulation in a wide spectral range as a function of an externally applied voltage. In this work, ECPs have been used in absorptive/transmissive electrochromic devices as candidates for smart window applications. The electrochromic devices were fabricated on flexible polyethylene substrates and used ECPs sandwiched between thin films of single-walled carbon nanotubes serving as conductive and flexible electrodes. Unlike ITO, the nanotube films are highly transmissive in the visible and infrared region of the spectrum. The transmission and reflection of the individual device components as well as assembled devices were measured over a wide spectral range (FIR to UV). The devices were switched in situ in the spectrometers. The optical constants of the constituent layers were calculated using the Drude-Lorentz model. The devices demonstrated high transmission contrasts between their colored and bleached states in the VIS, NIR, and MIR spectra, enabling electrically tunable control over the transmission or reflection of both light and heat. This control could lead to reduced heating or cooling costs in real world applications and the flexible nature of the device components allows many applications.

  2. Calibration of the Visible and Near-Infrared Channels of the Advanced Very High Resolution Radiometer (AVHRR) After Launch

    NASA Technical Reports Server (NTRS)

    Rao, C. R. Nagaraja; Chen, Jianhua

    1993-01-01

    The relative degradation in time of the visible(channel 1: approx.0.58-0.6 microns) and near-infrared(channel 2: approx. O.72-1.1 microns) channels of the Advanced Very High Resolution Radiometer(AVHRR), onboard the NOAA Polar-orbiting Operational Environmental Satellites(POES), has been determined, using the southeastern Libyan desert(21-23 deg N latitude; 28- 29 deg E longitude) as a time-invariant calibration target. A statistical procedure was used on the reflectance data for the two channels from the B3 data of the International Satellite Cloud Climatology Project(ISCCP) to obtain the degradation rates for the AVERRs on NOAA-7, -9, and -11 spacecraft. The degradation rates per year for channels 1 and 2 are respectively: 3.6% and 4.3%(NOAA-7); 5.9% and 3.5%(NOAA-9); and 1.2% and 2.0%(NOAA-11). The use of the degradation rates thus determined, in conjunction with 'absolute' calibrations obtained from congruent aircraft and satellite measurements, in the development of correction algorithms is illustrated with the AVHRR on the NOAA-9 spacecraft.

  3. Application of Visible and Near Infrared Spectroscopy for Rapid Analysis of Chrysin and Galangin in Chinese Propolis

    PubMed Central

    Nie, Pengcheng; Xia, Zhengyan; Sun, Da-Wen; He, Yong

    2013-01-01

    A novel method for the rapid determination of chrysin and galangin in Chinese propolis of poplar origin by means of visible and near infrared spectroscopy (Vis-NIR) was developed. Spectral data of 114 Chinese propolis samples were acquired in the 325 to 1,075 nm wavelength range using a Vis-NIR spectroradiometer. The reference values of chrysin and galangin of the samples were determined by high performance liquid chromatography (HPLC). Partial least squares (PLS) models were established using the spectra analyzed by different preprocessing methods. The effective wavelengths were selected by successive projections algorithm (SPA) and employed as the inputs of PLS, back propagation-artificial neural networks (BP-ANN), multiple linear regression (MLR) and least square-support vector machine (LS-SVM) models. The best results were achieved by SPA-BP-ANN models established with the Savitzky-Golay smoothing (SG) preprocessed spectra, where the r and RMSEP were 0.9823 and 1.5239 for galangin determination and 0.9668 and 2.4841 for chrysin determination, respectively. The results show that Vis-NIR demosntrates powerful capability for the rapid determination of chrysin and galangin contents in Chinese propolis. PMID:23945741

  4. Comparison of visible and near-infrared reflectance spectra of CM2 carbonaceous chondrites and primitive asteroids

    NASA Technical Reports Server (NTRS)

    Vilas, F.; Hiroi, T.; Zolensky, M. E.

    1993-01-01

    Spectra of primitive asteroids (defined as C, P, and D classes and associated subclasses) were compared to the limited number of spectra of CM2 carbonaceous chondrites. An absorption feature located at 0.7 microns attributed to an Fe(+2) - Fe(+3) charge transfer absorption in iron oxides in phyllosilicates is apparent in some of the CM2 carbonaceous chondrite spectra and many of the asteroid spectra. Sawyer found a correlation between the area of the 0.7 micron feature and the mean semimajor axis of the asteroids. Spectra of a larger sample of carbonaceous chondrites, including 7 CM2 chondrites, covering a spectral interval of 0.30-2.5 microns were recently obtained using the Relab instrument at Brown University. These spectra were compared with spectrophotometric asteroid observations in a separate abstract. Those spectra of CM2 chondrites were isolated into the UV, visible and near-infrared spectral regions in order to compare them with high-quality narrowband reflectance spectra.

  5. Wildlife Multispecies Remote Sensing Using Visible and Thermal Infrared Imagery Acquired from AN Unmanned Aerial Vehicle (uav)

    NASA Astrophysics Data System (ADS)

    Chrétien, L.-P.; Théau, J.; Ménard, P.

    2015-08-01

    Wildlife aerial surveys require time and significant resources. Multispecies detection could reduce costs to a single census for species that coexist spatially. Traditional methods are demanding for observers in terms of concentration and are not adapted to multispecies censuses. The processing of multispectral aerial imagery acquired from an unmanned aerial vehicle (UAV) represents a potential solution for multispecies detection. The method used in this study is based on a multicriteria object-based image analysis applied on visible and thermal infrared imagery acquired from a UAV. This project aimed to detect American bison, fallow deer, gray wolves, and elks located in separate enclosures with a known number of individuals. Results showed that all bison and elks were detected without errors, while for deer and wolves, 0-2 individuals per flight line were mistaken with ground elements or undetected. This approach also detected simultaneously and separately the four targeted species even in the presence of other untargeted ones. These results confirm the potential of multispectral imagery acquired from UAV for wildlife census. Its operational application remains limited to small areas related to the current regulations and available technology. Standardization of the workflow will help to reduce time and expertise requirements for such technology.

  6. Visible-lesion threshold dependency on retinal spot size for ultrashort laser pulses in the near infrared

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; Toth, Cynthia A.; Noojin, Gary D.; Stolarski, David J.; Payne, Dale J.; Rockwell, Benjamin A.

    1998-05-01

    Single pulses in the near-infrared (1060 nanometers) were used to measure retinal spot size dependence of minimum visible lesion (MVL) thresholds in rhesus monkey eyes at a pulsewidth of 150 femtoseconds. We report the MVL thresholds determined at 1 hour and 24 hours post exposure which were obtained with 2 different lenses placed in front of the eye to vary the retinal spot size. Also we report the fluorescein angiography thresholds (FAVL) for the above measurements. These new data points will be added to the databank for Retinal Maximum Permissible Exposure (MPE) as a function of spot size for this pulsewidth and a comparison will be made with previous spot size dependency studies. Our measurements show that the retinal ED50 threshold fluence decreases for increasing retinal spot sizes. The fluence at the MVL threshold decreased by a factor of 3 for an increase in retinal image diameter by a factor of 4.5 times from the smallest to largest spot size.

  7. Wavelength dependence of linear polarization in the visible and near infrared domain for large levitating grains (PROGRA2 instruments)

    NASA Astrophysics Data System (ADS)

    Renard, J.-B.; Hadamcik, E.; Couté, B.; Jeannot, M.; Levasseur-Regourd, A. C.

    2014-10-01

    Remote sensing measurements of light scattered by dust in solar system objects can provide clues on their physical properties. Databases obtained in the laboratory with numerous samples are necessary to interpret these measurements. We present here first studies of the wavelength dependence of the linear polarization between 545 nm and 1.5 μm, using the imaging polarimeters PROGRA2 for large levitating compact grains (PROGRA2-VIS in the visible domain, and the new instrument PROGRA2-IR in the near infrared). The measurements are conducted in microgravity conditions during parabolic flights for glass beads, quartz, sands, silicon carbides, anthracite, and lunar and Martian simulants. Comparison between measurements on glass beads and Mie calculations with glass spheres provides an assessment of the quality of the instruments. The dependence of the polarization on the wavelength is related to the complex refractive index of the particles, i.e. to their composition and to the size of the grains. More laboratory measurements will be necessary, in particular with smaller grains in aggregates, to better reproduce the remote sensing observations of solar system bodies.

  8. Detection and quantification of species authenticity and adulteration in crabmeat using visible and near-infrared spectroscopy.

    PubMed

    Gayo, Javier; Hale, Scott A

    2007-02-01

    Seafood processing often removes morphological properties of seafood species that enable the consumer to distinguish one type of organism from another. For this reason, species substitution is the most common form of economic adulteration in the seafood industry. Visible and near-infrared spectroscopy (Vis/NIR) has been used to detect and quantify species authenticity and adulteration in crabmeat samples. Atlantic blue crabmeat was adulterated with blue swimmer crabmeat in 10% increments. Water absorption bands dominated the main features in the crabmeat spectra, with a decrease in sample absorbance with increasing adulteration percentage. Several data pretreatments, i.e., moving average, combing, first and second derivatives, and multiplicative scatter correction, in addition to the raw data, were investigated for prediction and quantitative data analysis using partial least-squares. In addition, quantitative analysis was done using the full spectrum and a sequential approach in which 50 wavelengths were added sequentially to determine a new model and find an optimal solution. The results suggest that Vis/NIR spectroscopy is a suitable technology that can be applied to detect and quantify species authenticity and adulteration in crabmeat.

  9. A Non-Destructive Distinctive Method for Discrimination of Automobile Lubricant Variety by Visible and Short-Wave Infrared Spectroscopy

    PubMed Central

    Jiang, Lulu; Liu, Fei; He, Yong

    2012-01-01

    A novel method which is a combination of wavelet packet transform (WPT), uninformative variable elimination by partial least squares (UVE-PLS) and simulated annealing (SA) to extract best variance information among different varieties of lubricants is presented. A total of 180 samples (60 for each variety) were characterized on the basis of visible and short-wave infrared spectroscopy (VIS-SWNIR), and 90 samples (30 for each variety) were randomly selected for the calibration set, whereas, the remaining 90 samples (30 for each variety) were used for the validation set. The spectral data was split into different frequency bands by WPT, and different frequency bands were obtained. SA was employed to look for the best variance band (BVB) among different varieties of lubricants. In order to improve prediction precision further, BVB was processed by UVE-PLS and the optimal cutoff threshold of UVE was found by SA. Finally, five variables were mined, and were set as inputs for a least square-support vector machine (LS-SVM) to build the recognition model. An optimal model with a correlation coefficient (R) of 0.9850 and root mean square error of prediction (RMSEP) of 0.0827 was obtained. The overall results indicated that the method of combining WPT, UVE-PLS and SA was a powerful way to select diagnostic information for discrimination among different varieties of lubricating oil, furthermore, a more parsimonious and efficient LS-SVM model could be obtained. PMID:22737021

  10. Light-controlled release of nitric oxide from solid polymer composite materials using visible and near infra-red light.

    PubMed

    Mase, Jonathan D; Razgoniaev, Anton O; Tschirhart, Megan K; Ostrowski, Alexis D

    2015-04-01

    Photochemical Nitric oxide releasing composite materials (Photo-NORMs) were prepared using biocompatible polymers and the photochemical nitric oxide donor complex (CrONO). We have demonstrated nitric oxide (NO) release from the solid composites for extended (>30 hours) and controlled (20-100 pmoles s(-1)) durations after visible light irradiation. Quantitation of the efficiency of NO release from the composites shows that polymer gas permeability most dramatically affects the overall efficiency (QY) of photochemical NO release, where polymers with higher gas permeability have a higher QY of nitric oxide release. Composites were also prepared with β-phase lanthanide-doped NaYF4 upconverting nanoparticles (UCNPs). Controlled Nitric oxide release was achieved via near infrared (NIR) irradiation. A prototype LED device shows proof-of-concept that such photoresponsive NO-releasing composites could be applied to implantable systems, where the amount of NO released is modulated by changing irradiation time and light intensity. This research provides the guidelines necessary to move towards device fabrication and testing in actual tissue to evaluate the photo-NORMS as a reliable option for nitric oxide release in vivo.

  11. Triple-layer Fabry-Perot/SPP aluminum absorber in the visible and near-infrared region.

    PubMed

    Shu, Shiwei; Li, Yang Yang

    2015-03-15

    We report a theoretical study on a novel type of absorber that can achieve near perfect absorption in the visible and near-infrared regions by utilizing the Fabry-Perot and the surface plasmon polariton (SPP) effects. The absorber consists of an Al/dielectric/Al triple-layered structure with the top Al layer consisting of an array of holes. The absorption features can be easily controlled by tuning the structural parameters, particularly the porous features of the top Al layer. When the porous features in the top Al layer are significantly smaller than the wavelength, light absorption is enabled through the Fabry-Perot effect. On the other hand, when the porous features in the top layer are at the subwavelength scale, new absorption peaks emerge due to the SPP effect. Furthermore, when the top Al layer consists of an array of hollow rings, the electric field at the interface between the top Al layer and the middle dielectric layer is greatly enhanced due to the plasmonic effect, indicating that the absorber reported here may be suitable for novel applications, e.g., the surface-enhanced Raman spectroscopy (SERS) substrates.

  12. Aluminum nanopyramid array with tunable ultraviolet-visible-infrared wavelength plasmon resonances for rapid detection of carbohydrate antigen 199.

    PubMed

    Li, Wanbo; Qiu, Yongcai; Zhang, Li; Jiang, Lelun; Zhou, Zhangkai; Chen, Huanjun; Zhou, Jianhua

    2016-05-15

    Aluminum-based localized surface plasmon resonance (LSPR) holds attractive properties include low cost, high natural abundance, and ease of processing by a wide variety of methods including complementary metal oxide semiconductor process, making itself having an edge over conventional ones induced by noble metal. However, the inherent drawbacks of plasmonic mode limited on UV-green wavelength, low refractive index sensitivity, as well as heavy-shape-dependence greatly prevent aluminum plasmonics from real-life biosensing. Here, we demonstrated a uniform quasi-3-dimensional Al nanopyramid array (NPA) structure with tunable ultraviolet-visible-infrared (UV-vis-NIR) plasmon resonances for biosensing. By changing the reflection measuring angle, we could easily obtain typical peaks simultaneously exhibited on the reflectance spectrum across UV-vis-NIR wave region. The Al NPAs carried out high refractive index sensitivities which even comparable with that of noble metal, and can be used as a biosensor for directly detecting cytochrome c and carbohydrate antigen 199 in air after the sensing surface was washed cleanly and dried; the limits of detection were determined to be 800 nM and 29 ng/mL, respectively. Our proposed work therefore initiates the low-cost, high-performance biosensing using aluminum plasmonics, which would find wide applications in rapid diagnosis, mobile-healthcare and environmental monitoring.

  13. Rapid Erosion Modeling in a Western Kenya Watershed using Visible Near Infrared Reflectance, Classification Tree Analysis and 137Cesium

    PubMed Central

    deGraffenried, Jeff B.; Shepherd, Keith D.

    2010-01-01

    Human induced soil erosion has severe economic and environmental impacts throughout the world. It is more severe in the tropics than elsewhere and results in diminished food production and security. Kenya has limited arable land and 30 percent of the country experiences severe to very severe human induced soil degradation. The purpose of this research was to test visible near infrared diffuse reflectance spectroscopy (VNIR) as a tool for rapid assessment and benchmarking of soil condition and erosion severity class. The study was conducted in the Saiwa River watershed in the northern Rift Valley Province of western Kenya, a tropical highland area. Soil 137Cs concentration was measured to validate spectrally derived erosion classes and establish the background levels for difference land use types. Results indicate VNIR could be used to accurately evaluate a large and diverse soil data set and predict soil erosion characteristics. Soil condition was spectrally assessed and modeled. Analysis of mean raw spectra indicated significant reflectance differences between soil erosion classes. The largest differences occurred between 1,350 and 1,950 nm with the largest separation occurring at 1,920 nm. Classification and Regression Tree (CART) analysis indicated that the spectral model had practical predictive success (72%) with Receiver Operating Characteristic (ROC) of 0.74. The change in 137Cs concentrations supported the premise that VNIR is an effective tool for rapid screening of soil erosion condition. PMID:27397933

  14. Low-cost tissue simulating phantoms with adjustable wavelength-dependent scattering properties in the visible and infrared ranges

    NASA Astrophysics Data System (ADS)

    Saager, Rolf B.; Quach, Alan; Rowland, Rebecca A.; Baldado, Melissa L.; Durkin, Anthony J.

    2016-06-01

    We present a method for low-cost fabrication of polydimethylsiloxane (PDMS) tissue simulating phantoms with tunable scattering spectra, spanning visible, and near-infrared regimes. These phantoms use optical polishing agents (aluminum oxide powders) at various grit sizes to approximate in vivo tissue scattering particles across multiple size distributions (range: 17 to 3 μm). This class of tunable scattering phantoms is used to mimic distinct changes in wavelength-dependent scattering properties observed in tissue pathologies such as partial thickness burns. Described by a power-law dependence on wavelength, the scattering magnitude of these phantoms scale linearly with particle concentration over a physiologic range [μs‧=(0.5 to 2.0 mm-1)] whereas the scattering spectra, specific to each particle size distribution, correlate to distinct exponential coefficients (range: 0.007 to 0.32). Aluminum oxide powders used in this investigation did not detectably contribute to the absorption properties of these phantoms. The optical properties of these phantoms are verified through inverse adding-doubling methods and the tolerances of this fabrication method are discussed.

  15. Recognition of Banknote Fitness Based on a Fuzzy System Using Visible Light Reflection and Near-infrared Light Transmission Images.

    PubMed

    Kwon, Seung Yong; Pham, Tuyen Danh; Park, Kang Ryoung; Jeong, Dae Sik; Yoon, Sungsoo

    2016-01-01

    Fitness classification is a technique to assess the quality of banknotes in order to determine whether they are usable. Banknote classification techniques are useful in preventing problems that arise from the circulation of substandard banknotes (such as recognition failures, or bill jams in automated teller machines (ATMs) or bank counting machines). By and large, fitness classification continues to be carried out by humans, and this can cause the problem of varying fitness classifications for the same bill by different evaluators, and requires a lot of time. To address these problems, this study proposes a fuzzy system-based method that can reduce the processing time needed for fitness classification, and can determine the fitness of banknotes through an objective, systematic method rather than subjective judgment. Our algorithm was an implementation to actual banknote counting machine. Based on the results of tests on 3856 banknotes in United States currency (USD), 3956 in Korean currency (KRW), and 2300 banknotes in Indian currency (INR) using visible light reflection (VR) and near-infrared light transmission (NIRT) imaging, the proposed method was found to yield higher accuracy than prevalent banknote fitness classification methods. Moreover, it was confirmed that the proposed algorithm can operate in real time, not only in a normal PC environment, but also in an embedded system environment of a banknote counting machine. PMID:27294940

  16. Recognition of Banknote Fitness Based on a Fuzzy System Using Visible Light Reflection and Near-infrared Light Transmission Images.

    PubMed

    Kwon, Seung Yong; Pham, Tuyen Danh; Park, Kang Ryoung; Jeong, Dae Sik; Yoon, Sungsoo

    2016-06-11

    Fitness classification is a technique to assess the quality of banknotes in order to determine whether they are usable. Banknote classification techniques are useful in preventing problems that arise from the circulation of substandard banknotes (such as recognition failures, or bill jams in automated teller machines (ATMs) or bank counting machines). By and large, fitness classification continues to be carried out by humans, and this can cause the problem of varying fitness classifications for the same bill by different evaluators, and requires a lot of time. To address these problems, this study proposes a fuzzy system-based method that can reduce the processing time needed for fitness classification, and can determine the fitness of banknotes through an objective, systematic method rather than subjective judgment. Our algorithm was an implementation to actual banknote counting machine. Based on the results of tests on 3856 banknotes in United States currency (USD), 3956 in Korean currency (KRW), and 2300 banknotes in Indian currency (INR) using visible light reflection (VR) and near-infrared light transmission (NIRT) imaging, the proposed method was found to yield higher accuracy than prevalent banknote fitness classification methods. Moreover, it was confirmed that the proposed algorithm can operate in real time, not only in a normal PC environment, but also in an embedded system environment of a banknote counting machine.

  17. Potential use of visible and near-infrared spectroscopy for the analysis and diagnosis of chronic fatigue syndrome (Review).

    PubMed

    Sakudo, Akikazu

    2016-09-01

    At present, chronic fatigue syndrome (CFS) is diagnosed on the basis of clinical symptoms. Although various psychological, endocrinological and immunological abnormalities of patients with CFS have been reported, no clear consensus exists regarding the symptoms for this disorder. Thus, an objective diagnostic method for CFS is urgently required. The present study investigated the diagnosis and analysis of CFS using visible and near‑infrared (Vis‑NIR) spectroscopy. Previous studies have demonstrated the potential of Vis-NIR spectroscopy for diagnosing CFS by analyzing either serum samples as an invasive approach or thumbs as a non‑invasive approach. Analysis of the Vis‑NIR spectra of blood and thumbs suggested that factors absorbing in this spectral region are altered in patients with CFS compared with healthy individuals. These findings are likely to facilitate the search for biomarkers associated with CFS and to increase our understanding of the pathophysiology of the disorder. The current review aimed to outline the latest studies and discuss the future perspectives for CFS made possible by Vis-NIR spectroscopy. PMID:27430297

  18. Thermal radiative and thermodynamic properties of solid and liquid uranium and plutonium carbides in the visible-near-infrared range

    NASA Astrophysics Data System (ADS)

    Fisenko, Anatoliy I.; Lemberg, Vladimir F.

    2016-09-01

    The knowledge of thermal radiative and thermodynamic properties of uranium and plutonium carbides under extreme conditions is essential for designing a new metallic fuel materials for next generation of a nuclear reactor. The present work is devoted to the study of the thermal radiative and thermodynamic properties of liquid and solid uranium and plutonium carbides at their melting/freezing temperatures. The Stefan-Boltzmann law, total energy density, number density of photons, Helmholtz free energy density, internal energy density, enthalpy density, entropy density, heat capacity at constant volume, pressure, and normal total emissivity are calculated using experimental data for the frequency dependence of the normal spectral emissivity of liquid and solid uranium and plutonium carbides in the visible-near infrared range. It is shown that the thermal radiative and thermodynamic functions of uranium carbide have a slight difference during liquid-to-solid transition. Unlike UC, such a difference between these functions have not been established for plutonium carbide. The calculated values for the normal total emissivity of uranium and plutonium carbides at their melting temperatures is in good agreement with experimental data. The obtained results allow to calculate the thermal radiative and thermodynamic properties of liquid and solid uranium and plutonium carbides for any size of samples. Based on the model of Hagen-Rubens and the Wiedemann-Franz law, a new method to determine the thermal conductivity of metals and carbides at the melting points is proposed.

  19. Recognition of Banknote Fitness Based on a Fuzzy System Using Visible Light Reflection and Near-infrared Light Transmission Images

    PubMed Central

    Kwon, Seung Yong; Pham, Tuyen Danh; Park, Kang Ryoung; Jeong, Dae Sik; Yoon, Sungsoo

    2016-01-01

    Fitness classification is a technique to assess the quality of banknotes in order to determine whether they are usable. Banknote classification techniques are useful in preventing problems that arise from the circulation of substandard banknotes (such as recognition failures, or bill jams in automated teller machines (ATMs) or bank counting machines). By and large, fitness classification continues to be carried out by humans, and this can cause the problem of varying fitness classifications for the same bill by different evaluators, and requires a lot of time. To address these problems, this study proposes a fuzzy system-based method that can reduce the processing time needed for fitness classification, and can determine the fitness of banknotes through an objective, systematic method rather than subjective judgment. Our algorithm was an implementation to actual banknote counting machine. Based on the results of tests on 3856 banknotes in United States currency (USD), 3956 in Korean currency (KRW), and 2300 banknotes in Indian currency (INR) using visible light reflection (VR) and near-infrared light transmission (NIRT) imaging, the proposed method was found to yield higher accuracy than prevalent banknote fitness classification methods. Moreover, it was confirmed that the proposed algorithm can operate in real time, not only in a normal PC environment, but also in an embedded system environment of a banknote counting machine. PMID:27294940

  20. Using airborne thermal infrared imagery and helicopter EM conductivity to locate mine pools and discharges in the Kettle Creek watershed, north-central Pennsylvania

    SciTech Connect

    Love, E.; Hammack, R.W.; Harbert, W.P.; Sams, J.I.; Veloski, G.A.; Ackman, T.E.

    2005-11-01

    The Kettle Creek watershed contains 50–100-year-old surface and underground coal mines that are a continuing source of acid mine drainage (AMD). To characterize the mining-altered hydrology of this watershed, an airborne reconnaissance was conducted in 2002 using airborne thermal infrared imagery (TIR) and helicopter-mounted electromagnetic (HEM) surveys. TIR uses the temperature differential between surface water and groundwater to locate areas where groundwater emerges at the surface. TIR anomalies located in the survey included seeps and springs, as well as mine discharges. In a follow-up ground investigation, hand-held GPS units were used to locate 103 of the TIR anomalies. Of the sites investigated, 26 correlated with known mine discharges, whereas 27 were previously unknown. Seven known mine discharges previously obscured from TIR imagery were documented. HEM surveys were used to delineate the groundwater table and also to locate mine pools, mine discharges, and groundwater recharge zones. These surveys located 12 source regions and flow paths for acidic, metal-containing (conductive) mine drainage; areas containing acid-generating mine spoil; and areas of groundwater recharge and discharge, as well as identifying potential mine discharges previously obscured from TIR imagery by nondeciduous vegetation. Follow-up ground-based electromagnetic surveys verified the results of the HEM survey. Our study suggests that airborne reconnaissance can make the remediation of large watersheds more efficient by focusing expensive ground surveys on small target areas.