Science.gov

Sample records for high-resolution snapshot imaging

  1. High-intensity x-ray holography: an approach to high-resolution snapshot imaging of biological specimens

    SciTech Connect

    Solem, J.C.

    1982-08-01

    The crucial physical and technological issues pertaining to the holographic imaging of biological structures with a short-pulse, high-intensity, high-quantum-energy laser were examined. The limitations of x-ray optics are discussed. Alternative holographic techniques were considered, and it was concluded that far-field Fresnel transform holography (Fraunhofer holography) using a photoresist recording surface is most tractable with near term technology. The hydrodynamic expansion of inhomogeneities within the specimen is discussed. It is shown that expansion is the major source of image blurring. Analytic expressions were derived for the explosion of protein concentrations in an x-ray transparent cytoplasm, compared with numerical calculations, and corrections derived to account for the competitive transport processes by which these inhomogeneities lose energy. It is concluded that for the near term Fresnel transform holography, particularly, far-field or Fraunhofer holography, is more practical than Fourier transform holography. Of the alternative fine grain recording media for use with Fresnel transform holography, a photo-resist is most attractive. For best resolution, exposure times must be limited to a few picoseconds, and this calls for investigation of mechanisms to shutter the laser or gate the recording surface. The best contrast ratio between the nitrogen-bearing polymers (protein and the nucleic acids) and water is between the K-edges of oxygen and nitrogen.

  2. High Resolution Doppler Imager

    NASA Technical Reports Server (NTRS)

    Hays, Paul B.

    1999-01-01

    This report summarizes the accomplishments of the High Resolution Doppler Imager (HRDI) on UARS spacecraft during the period 4/l/96 - 3/31/99. During this period, HRDI operation, data processing, and data analysis continued, and there was a high level of vitality in the HRDI project. The HRDI has been collecting data from the stratosphere, mesosphere, and lower thermosphere since instrument activation on October 1, 1991. The HRDI team has stressed three areas since operations commenced: 1) operation of the instrument in a manner which maximizes the quality and versatility of the collected data; 2) algorithm development and validation to produce a high-quality data product; and 3) scientific studies, primarily of the dynamics of the middle atmosphere. There has been no significant degradation in the HRDI instrument since operations began nearly 8 years ago. HRDI operations are fairly routine, although we have continued to look for ways to improve the quality of the scientific product, either by improving existing modes, or by designing new ones. The HRDI instrument has been programmed to collect data for new scientific studies, such as measurements of fluorescence from plants, measuring cloud top heights, and lower atmosphere H2O.

  3. High resolution imaging

    NASA Technical Reports Server (NTRS)

    Goody, R.; Papaliolios, C.; Beletic, J.

    1986-01-01

    Diffraction-limited telescopic observations were obtained of solar system objects and a program of research into Uranus, Neptune, Pluto and the asteroids based upon the data obtained was persued. Two camera systems appropriate for this work were developed. Most importantly, the PAPA photon address camera was developed and proven. Algorithms were developed for both phase and amplitude recovery and were validated on theoretical and laboratory data and to a limited extent on telescopic data. A laboratory simulator was constructed that was used for development but is also available for controlled investigation of image reconstruction. During 1985 two successful expeditions were made to Hawaii and Cerro Tololo and a large body of data on Pluto, Uranus, Neptune and two asteroids are on tape.

  4. High-Resolution Radar Imaging

    DTIC Science & Technology

    1990-01-14

    vThe goal of this project is to formulate and investigate new approaches for forming images of radar targets from spotlight-mode, delay-doppler...the new methods we are studying. There are two modules in the program. The first module produces simulated radar back-scatter data. The simulation...gives the model and fundamental estimation equations for the method we are developing. The abstract is: "A new approach to high resolution radar

  5. High resolution imaging at Palomar

    NASA Technical Reports Server (NTRS)

    Kulkarni, Shrinivas R.

    1992-01-01

    For the last two years we have embarked on a program of understanding the ultimate limits of ground-based optical imaging. We have designed and fabricated a camera specifically for high resolution imaging. This camera has now been pressed into service at the prime focus of the Hale 5 m telescope. We have concentrated on two techniques: the Non-Redundant Masking (NRM) and Weigelt's Fully Filled Aperture (FFA) method. The former is the optical analog of radio interferometry and the latter is a higher order extension of the Labeyrie autocorrelation method. As in radio Very Long Baseline Interferometry (VLBI), both these techniques essentially measure the closure phase and, hence, true image construction is possible. We have successfully imaged binary stars and asteroids with angular resolution approaching the diffraction limit of the telescope and image quality approaching that of a typical radio VLBI map. In addition, we have carried out analytical and simulation studies to determine the ultimate limits of ground-based optical imaging, the limits of space-based interferometric imaging, and investigated the details of imaging tradeoffs of beam combination in optical interferometers.

  6. A Snapshot Imaging Spectropolarimeter

    DTIC Science & Technology

    2001-08-01

    Distribution UnliuLt:ýJ Abstract A revolutionary technique for snapshot imaging spectropolarimetry has been developed because of the recent availability...of large focal plane arrays and fast computers. The technique involves the combination of spectropolarimetry with computed tomography imaging...operate through the fusion of two techniques: channeled spectropolarimetry " 2 and computed tomography imaging spectrometry. Accordingly, it is

  7. HIRAS, high resolution IRAS images

    NASA Astrophysics Data System (ADS)

    Bontekoe, Tj. R.; Kester, D. J. M.; Wesselius, P. R.

    The IRAS Software Telescope allows everyone to obtain the state-of-the-art IRAS products (survey, pointed observations, as well as low-resolution spectra) from raw uncalibrated scan data to FITS maps and any stage in between, any size area up to five by five degree, within 24 hours response time, and without the tedious proposal and refereeing process. This is done via an electronic mail server, without manual interaction. High Resolution Images can also be made by running HIRAS, which drives the MemSys5 (Gull & Skilling 1991) maximum entropy package. Herewith a resolution of order one arc-minute, instead of the usual five arc-minutes, can be obtained.

  8. High-resolution infrared imaging

    NASA Astrophysics Data System (ADS)

    Falco, Charles M.

    2010-08-01

    The hands and mind of an artist are intimately involved in the creative process of image formation, intrinsically making paintings significantly more complex than photographs to analyze. In spite of this difficulty, several years ago the artist David Hockney and I identified optical evidence within a number of paintings that demonstrated artists began using optical projections as early as c1425 - nearly 175 years before Galileo - as aids for producing portions of their images. In the course of our work, Hockney and I developed insights that I have been applying to a new approach to computerized image analysis. Recently I developed and characterized a portable high resolution infrared for capturing additional information from paintings. Because many pigments are semi-transparent in the IR, in a number of cases IR photographs ("reflectograms") have revealed marks made by the artists that had been hidden under paint ever since they were made. I have used this IR camera to capture photographs ("reflectograms") of hundreds of paintings in over a dozen museums on three continents and, in some cases, these reflectograms have provided new insights into decisions the artists made in creating the final images that we see in the visible.

  9. Snapshot-Imaging Spectropolarimeter

    DTIC Science & Technology

    2005-11-17

    this backprojection+filtering is the process that the pseudoinverse matrix represents for this system. 3. CHANNELLED SPECTROPOLARIMETRY (CHSP...channel shown in Fig. 9.8 4. SNAPSHOT IMAGING SPECTROPOLARIMETRY (CTICS) By combining the techniques of CTIS with CHSP, we can construct an instrument... spectropolarimetry . PhD thesis, University of Arizona, Tucson, Arizona, 2002. 9. D. H. Goldstein, D. B. Chenault, W. G. Egan, and M. J. Duggin, eds., Polarization Analysis, Measurement, and Remote Sensing IV, Proc. SPIE 4481, 2001. 20

  10. High Resolution Orientation Imaging Microscopy

    DTIC Science & Technology

    2012-05-02

    Functions, ICCES 2010, Las Vegas. 17. David Fullwood, Brent Adams, Mike Miles, Stuart Rogers, Ali Khosravani, Raj Mishra, Design for Ductility : Defect... Pseudo -Symmetries by High Resolution EBSD Methods, MS&T. 2009: Pittsburgh. 27. Oliver Johnson, Calvin Gardner, David Fullwood, Brent Adams, George...applied to strain measurements ................................... 6 2.3 Recovery of Lattice Tetragonality and Pseudo -Symmetry Resolution

  11. High Resolution Frequency Swept Imaging.

    DTIC Science & Technology

    1980-02-14

    image resolution comparable to an ordinary photographic camera. In addition to inconvenient size, the cost of filling such a large aperture with... cost of implementing a LFTDR. Because of the large difference between the high frequency imaging frequencies and the low frequency reference frequency... cost . In addition since the measured reference phase must be multiplied by a factor a equal to the ratio of the imaging to the reference frequency

  12. Semiconductor crystal high resolution imager

    NASA Technical Reports Server (NTRS)

    Levin, Craig S. (Inventor); Matteson, James (Inventor)

    2011-01-01

    A radiation imaging device (10). The radiation image device (10) comprises a subject radiation station (12) producing photon emissions (14), and at least one semiconductor crystal detector (16) arranged in an edge-on orientation with respect to the emitted photons (14) to directly receive the emitted photons (14) and produce a signal. The semiconductor crystal detector (16) comprises at least one anode and at least one cathode that produces the signal in response to the emitted photons (14).

  13. Miniature snapshot multispectral imager

    NASA Astrophysics Data System (ADS)

    Gupta, Neelam; Ashe, Philip R.; Tan, Songsheng

    2011-03-01

    We present a miniature snapshot multispectral imager based on using a monolithic filter array that operates in the short wavelength infrared spectral region and has a number of defense and commercial applications. The system is low-weight, portable with a miniature platform, and requires low power. The imager uses a 4×4 Fabry-Pérot filter array operating from 1487 to 1769 nm with a spectral bandpass ~10 nm. The design of the filters is based on using a shadow mask technique to fabricate an array of Fabry-Pérot etalons with two multilayer dielectric mirrors. The filter array is installed in a commercial handheld InGaAs camera, replacing the imaging lens with a custom designed 4×4 microlens assembly with telecentric imaging performance in each of the 16 subimaging channels. We imaged several indoor and outdoor scenes. The microlens assembly and filter design is quite flexible and can be tailored for any wavelength region from the ultraviolet to the longwave infrared, and the spectral bandpass can also be customized to meet sensing requirements. In this paper we discuss the design and characterization of the filter array, the microlens optical assembly, and imager and present imaging results.

  14. Passive High Resolution RF Imaging

    DTIC Science & Technology

    2006-05-02

    sensing applications: 1. Imaging with potential resolution of meters sq. 1.1 Forests areas controlling 1.2 Foliage mass evaluation 1.3...from TOPCON. Currently, work is in progress to study and customise the software and satellite position extraction from the receiver. 6. BRIEF

  15. High Resolution Frequency Swept Imaging.

    DTIC Science & Technology

    1983-09-30

    elements can be em- ployed to cut cost. However a systematic study of ordered and random aperture thinning [1], [21 Indicates rapid deterioration in...yield 3-D image information. Impulse illumination is desirable incertain instances of rapid target motion but may be more difficlt to implement than...various slices are seen in depth * at different VFT planes that are determined by the positions of the axially incremented point source. Repeated rapid

  16. High Resolution Imaging with AEOS

    SciTech Connect

    Patience, J; Macintosh, B A; Max, C E

    2001-08-27

    The U. S. Air Force Advanced Electro-Optical System (AEOS) which includes a 941 actuator adaptive optics system on a 3.7m telescope has recently been made available for astronomical programs. Operating at a wavelength of 750 nm, the diffraction-limited angular resolution of the system is 0.04 inches; currently, the magnitude limit is V {approx} 7 mag. At the distances of nearby open clusters, diffraction-limited images should resolve companions with separations as small as 4-6 AU--comparable to the Sun-Jupiter distance. The ability to study such close separations is critical, since most companions are expected to have separations in the few AU to tens of AU range. With the exceptional angular resolution of the current AEOS setup, but restricted target magnitude range, we are conducting a companion search of a large, well-defined sample of bright early-type stars in nearby open clusters and in the field. Our data set will both characterize this relatively new adaptive optics system and answer questions in binary star formation and stellar X-ray activity. We will discuss our experience using AEOS, the data analysis involved, and our initial results.

  17. Pyramidal fractal dimension for high resolution images.

    PubMed

    Mayrhofer-Reinhartshuber, Michael; Ahammer, Helmut

    2016-07-01

    Fractal analysis (FA) should be able to yield reliable and fast results for high-resolution digital images to be applicable in fields that require immediate outcomes. Triggered by an efficient implementation of FA for binary images, we present three new approaches for fractal dimension (D) estimation of images that utilize image pyramids, namely, the pyramid triangular prism, the pyramid gradient, and the pyramid differences method (PTPM, PGM, PDM). We evaluated the performance of the three new and five standard techniques when applied to images with sizes up to 8192 × 8192 pixels. By using artificial fractal images created by three different generator models as ground truth, we determined the scale ranges with minimum deviations between estimation and theory. All pyramidal methods (PM) resulted in reasonable D values for images of all generator models. Especially, for images with sizes ≥1024×1024 pixels, the PMs are superior to the investigated standard approaches in terms of accuracy and computation time. A measure for the possibility to differentiate images with different intrinsic D values did show not only that the PMs are well suited for all investigated image sizes, and preferable to standard methods especially for larger images, but also that results of standard D estimation techniques are strongly influenced by the image size. Fastest results were obtained with the PDM and PGM, followed by the PTPM. In terms of absolute D values best performing standard methods were magnitudes slower than the PMs. Concluding, the new PMs yield high quality results in short computation times and are therefore eligible methods for fast FA of high-resolution images.

  18. High-Resolution Anamorphic SPECT Imaging

    PubMed Central

    Durko, Heather L.; Barrett, Harrison H.; Furenlid, Lars R.

    2015-01-01

    We have developed a gamma-ray imaging system that combines a high-resolution silicon detector with two sets of movable, half-keel-edged copper-tungsten blades configured as crossed slits. These apertures can be positioned independently between the object and detector, producing an anamorphic image in which the axial and transaxial magnifications are not constrained to be equal. The detector is a 60 mm × 60 mm, one-millimeter-thick, one-megapixel silicon double-sided strip detector with a strip pitch of 59 μm. The flexible nature of this system allows the application of adaptive imaging techniques. We present system details; calibration, acquisition, and reconstruction methods; and imaging results. PMID:26160983

  19. High resolution millimeter-wave imaging sensor

    NASA Technical Reports Server (NTRS)

    Wilson, W. J.; Howard, R. J.; Parks, G. S.

    1985-01-01

    A scanning 3-mm radiometer is described that has been built for use on a small aircraft to produce real time high resolution images of the ground when atmospheric conditions such as smoke, dust, and clouds make IR and visual sensors unusable. The sensor can be used for a variety of remote sensing applications such as measurements of snow cover and snow water equivalent, precipitation mapping, vegetation type and extent, surface moisture and temperature, and surface thermal inertia. The advantages of millimeter waves for cloud penetration and the ability to observe different physical phenomena make this system an attractive supplement to visible and IR remote sensing systems.

  20. Limiting liability via high resolution image processing

    SciTech Connect

    Greenwade, L.E.; Overlin, T.K.

    1996-12-31

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as `evidence ready`, even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  1. Ultra-high resolution computed tomography imaging

    DOEpatents

    Paulus, Michael J.; Sari-Sarraf, Hamed; Tobin, Jr., Kenneth William; Gleason, Shaun S.; Thomas, Jr., Clarence E.

    2002-01-01

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  2. LWIR Snapshot Imaging Polarimeter

    SciTech Connect

    Dr. Robert E Sampson

    2009-04-01

    This report describes the results of a phase 1 STTR to design a longwave infrared imaging polarimeter. The system design, expected performance and components needed to construct the imaging polarimeter are described. Expected performance is modeled and sytem specifications are presented.

  3. High-resolution imaging using endoscopic holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1990-08-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help to their control. 1.

  4. Holographic high-resolution endoscopic image recording

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1991-03-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help

  5. High-resolution ophthalmic imaging system

    DOEpatents

    Olivier, Scot S.; Carrano, Carmen J.

    2007-12-04

    A system for providing an improved resolution retina image comprising an imaging camera for capturing a retina image and a computer system operatively connected to the imaging camera, the computer producing short exposures of the retina image and providing speckle processing of the short exposures to provide the improved resolution retina image. The system comprises the steps of capturing a retina image, producing short exposures of the retina image, and speckle processing the short exposures of the retina image to provide the improved resolution retina image.

  6. "Phase-Enhanced" 3D Snapshot ISAR Imaging and Interferometric SAR

    DTIC Science & Technology

    2009-12-28

    document when it is no longer needed. Massachusetts Institute of Technology Lincoln Laboratory ttPhase-Lnhanced,, 3D Snapshot ISAR Imaging and...inverse synthetie aperture radar ( ISAR ) images based on recent developments in high resolution spectral estimation theory. Because this technique requires...the radar sensor. This report develops a framework based on 3D snapshot imaging of sparse angle sectors of ISAR data, extending these results to 3D

  7. High Resolution Image From Viking Lander 1

    NASA Image and Video Library

    1996-12-12

    NASA's Viking 1 took this high-resolution picture today, its third day on Mars. Distance from the camera to the nearfield (bottom) is about 4 meters (13 feet); to the horizon, about 3 kilometers (1.8 miles). The photo shows numerous angular blocks ranging in size from a few centimeters to several meters. The surface between the blocks is composed of fine-grained material. Accumulation of some fine-grained material behind blocks indicates wind deposition of dust and sand downwind of obstacles. The large block on the horizon is about 4 meters (13 feet) wide. Distance across the horizon is about 34 meters (110 feet). http://photojournal.jpl.nasa.gov/catalog/PIA00385

  8. Multiple snapshot colored compressive spectral imager

    NASA Astrophysics Data System (ADS)

    Correa, Claudia V.; Hinojosa, Carlos A.; Arce, Gonzalo R.; Arguello, Henry

    2017-04-01

    The snapshot colored compressive spectral imager (SCCSI) is a recent compressive spectral imaging (CSI) architecture that senses the spatial and spectral information of a scene in a single snapshot by means of a colored mosaic FPA detector and a dispersive element. Commonly, CSI architectures allow multiple snapshot acquisition, yielding improved reconstructions of spatially detailed and spectrally rich scenes. Each snapshot is captured employing a different coding pattern. In principle, SCCSI does not admit multiple snapshots since the pixelated tiling of optical filters is directly attached to the detector. This paper extends the concept of SCCSI to a system admitting multiple snapshot acquisition by rotating the dispersive element, so the dispersed spatio-spectral source is coded and integrated at different detector pixels in each rotation. Thus, a different set of coded projections is captured using the same optical components of the original architecture. The mathematical model of the multishot SCCSI system is presented along with several simulations. Results show that a gain up to 7 dB of peak signal-to-noise ratio is achieved when four SCCSI snapshots are compared to a single snapshot reconstruction. Furthermore, a gain up to 5 dB is obtained with respect to state-of-the-art architecture, the multishot CASSI.

  9. Spatially adaptive regularized iterative high-resolution image reconstruction algorithm

    NASA Astrophysics Data System (ADS)

    Lim, Won Bae; Park, Min K.; Kang, Moon Gi

    2000-12-01

    High resolution images are often required in applications such as remote sensing, frame freeze in video, military and medical imaging. Digital image sensor arrays, which are used for image acquisition in many imaging systems, are not dense enough to prevent aliasing, so the acquired images will be degraded by aliasing effects. To prevent aliasing without loss of resolution, a dense detector array is required. But it may be very costly or unavailable, thus, many imaging systems are designed to allow some level of aliasing during image acquisition. The purpose of our work is to reconstruct an unaliased high resolution image from the acquired aliased image sequence. In this paper, we propose a spatially adaptive regularized iterative high resolution image reconstruction algorithm for blurred, noisy and down-sampled image sequences. The proposed approach is based on a Constrained Least Squares (CLS) high resolution reconstruction algorithm, with spatially adaptive regularization operators and parameters. These regularization terms are shown to improve the reconstructed image quality by forcing smoothness, while preserving edges in the reconstructed high resolution image. Accurate sub-pixel motion registration is the key of the success of the high resolution image reconstruction algorithm. However, sub-pixel motion registration may have some level of registration error. Therefore, a reconstruction algorithm which is robust against the registration error is required. The registration algorithm uses a gradient based sub-pixel motion estimator which provides shift information for each of the recorded frames. The proposed algorithm is based on a technique of high resolution image reconstruction, and it solves spatially adaptive regularized constrained least square minimization functionals. In this paper, we show that the reconstruction algorithm gives dramatic improvements in the resolution of the reconstructed image and is effective in handling the aliased information. The

  10. O-space with high resolution readouts outperforms radial imaging.

    PubMed

    Wang, Haifeng; Tam, Leo; Kopanoglu, Emre; Peters, Dana C; Constable, R Todd; Galiana, Gigi

    2017-04-01

    While O-Space imaging is well known to accelerate image acquisition beyond traditional Cartesian sampling, its advantages compared to undersampled radial imaging, the linear trajectory most akin to O-Space imaging, have not been detailed. In addition, previous studies have focused on ultrafast imaging with very high acceleration factors and relatively low resolution. The purpose of this work is to directly compare O-Space and radial imaging in their potential to deliver highly undersampled images of high resolution and minimal artifacts, as needed for diagnostic applications. We report that the greatest advantages to O-Space imaging are observed with extended data acquisition readouts. A sampling strategy that uses high resolution readouts is presented and applied to compare the potential of radial and O-Space sequences to generate high resolution images at high undersampling factors. Simulations and phantom studies were performed to investigate whether use of extended readout windows in O-Space imaging would increase k-space sampling and improve image quality, compared to radial imaging. Experimental O-Space images acquired with high resolution readouts show fewer artifacts and greater sharpness than radial imaging with equivalent scan parameters. Radial images taken with longer readouts show stronger undersampling artifacts, which can cause small or subtle image features to disappear. These features are preserved in a comparable O-Space image. High resolution O-Space imaging yields highly undersampled images of high resolution and minimal artifacts. The additional nonlinear gradient field improves image quality beyond conventional radial imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Distributed MIMO Radar for Imaging and High Resolution Target Localization

    DTIC Science & Technology

    2012-02-02

    28-2012 Final Report 04/15/2009 - 11/30/2011 Distributed MIMO Radar for Imaging and High Resolution Target Localization FA9550-09-1-0303 Alexander M...randomly placed sensors. MIMO radar, High-Resolution radar 19 Distributed MIMO Radar for Imaging and High Resolution Target Localization Air Force Office...configured with its antennas collocated [6] or distributed over an area [7, 8]. We refer to radio elements of a MIMO radar as nodes. Nodes may be equipped

  12. High resolution imaging of live mitochondria.

    PubMed

    Jakobs, Stefan

    2006-01-01

    Classically, mitochondria have been studied by biochemical, genetic and electron microscopic approaches. In the last two decades, it became evident that mitochondria are highly dynamic organelles that are frequently dividing and fusing, changing size and shape and traveling long distances throughout the life of a cell. The study of the complex structural changes of mitochondria in vivo became possible with the advent of fluorescent labeling techniques in combination with live cell imaging microscopy. This review aims to provide an overview on novel fluorescent markers that are used in combination with mitochondrial fusion assays and various live cell microscopy techniques to study mitochondrial dynamics. In particular, approaches to study the movement of mitochondrial proteins and novel imaging techniques (FRET imaging-, 4Pi- and STED-microscopy) that provide high spatial resolution are considered.

  13. High resolution in galaxy photometry and imaging

    NASA Astrophysics Data System (ADS)

    Nieto, J.-L.; Lelievre, G.

    Techniques for increasing the resolution of ground-based photometric observations of galaxies are discussed. The theoretical limitations on resolution and their implications for choosing telescope size at a given site considered, with an emphasis on the importance of the Fried (1966) parameter r0. The techniques recommended are shortening exposure time, selection of the highest-resolution images, and a posteriori digital image processing (as opposed to active-mirror image stabilization or the cine-CCD system of Fort et al., 1984). The value of the increased resolution (by a factor of 2) achieved at Pic du Midi observatory for studies of detailed structure in extragalactic objects, for determining the distance to galaxies, and for probing the central cores of galaxies is indicated.

  14. Reproducible high-resolution multispectral image acquisition in dermatology

    NASA Astrophysics Data System (ADS)

    Duliu, Alexandru; Gardiazabal, José; Lasser, Tobias; Navab, Nassir

    2015-07-01

    Multispectral image acquisitions are increasingly popular in dermatology, due to their improved spectral resolution which enables better tissue discrimination. Most applications however focus on restricted regions of interest, imaging only small lesions. In this work we present and discuss an imaging framework for high-resolution multispectral imaging on large regions of interest.

  15. High-Resolution MOC Image of Phobos

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. This image shows a close-up of the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater, and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Thermal Emission Spectrometer is operated by Arizona State University and was built by Raytheon Santa Barbara Remote Sensing. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  16. High-Resolution MOC Image of Phobos

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. This image shows a close-up of the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater, and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Thermal Emission Spectrometer is operated by Arizona State University and was built by Raytheon Santa Barbara Remote Sensing. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  17. Invariant high resolution optical skin imaging

    NASA Astrophysics Data System (ADS)

    Murali, Supraja; Rolland, Jannick

    2007-02-01

    Optical Coherence Microscopy (OCM) is a bio-medical low coherence interferometric imaging technique that has become a topic of active research because of its ability to provide accurate, non-invasive cross-sectional images of biological tissue with much greater resolution than the current common technique ultrasound. OCM is a derivative of Optical Coherence Tomography (OCT) that enables greater resolution imposed by the implementation of an optical confocal design involving high numerical aperture (NA) focusing in the sample. The primary setback of OCM, however is the depth dependence of the lateral resolution obtained that arises from the smaller depth of focus of the high NA beam. We propose to overcome this limitation using a dynamic focusing lens design that can achieve quasi-invariant lateral resolution up to 1.5mm depth of skin tissue.

  18. High resolution image measurements of nuclear tracks

    NASA Technical Reports Server (NTRS)

    Shirk, E. K.; Price, P. B.

    1980-01-01

    The striking clarity and high contrast of the mouths of tracks etched in CR-39 plastic detectors allow automatic measurement of track parameters to be made with simple image-recognition equipment. Using a commercially available Vidicon camera system with a microprocessor-controlled digitizer, resolution for normally incident C-12 and N-14 ions at 32 MeV/amu equivalent to a 14sigma separation of adjacent charges was demonstrated.

  19. Medusae Fossae Formation - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. The crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

    The image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The best Viking view of the area (VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  20. Medusae Fossae Formation - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. The crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

    The image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The best Viking view of the area (VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  1. High-resolution colorimetric imaging of paintings

    NASA Astrophysics Data System (ADS)

    Martinez, Kirk; Cupitt, John; Saunders, David R.

    1993-05-01

    With the aim of providing a digital electronic replacement for conventional photography of paintings, a scanner has been constructed based on a 3000 X 2300 pel resolution camera which is moved precisely over a 1 meter square area. Successive patches are assembled to form a mosaic which covers the whole area at c. 20 pels/mm resolution, which is sufficient to resolve the surface textures, particularly craquelure. To provide high color accuracy, a set of seven broad-band interference filters are used to cover the visible spectrum. A calibration procedure based upon a least-mean-squares fit to the color of patches from a Macbeth Colorchecker chart yields an average color accuracy of better than 3 units in the CMC uniform color space. This work was mainly carried out as part of the VASARI project funded by the European Commission's ESPRIT program, involving companies and galleries from around Europe. The system is being used to record images for conservation research, for archival purposes and to assist in computer-aided learning in the field of art history. The paper will describe the overall system design, including the selection of the various hardware components and the design of controlling software. The theoretical basis for the color calibration methodology is described as well as the software for its practical implementation. The mosaic assembly procedure and some of the associated image processing routines developed are described. Preliminary results from the research will be presented.

  2. High-resolution imaging with AEOS

    NASA Astrophysics Data System (ADS)

    Patience, Jennifer; Macintosh, Bruce A.; Max, Claire E.

    2001-12-01

    The U.S. Air Force Advanced Electro-Optical System (AEOS) which includes a 941 actuator adaptive optics system on a 3.7 m telescope has recently been made available for astronomical programs. Operating at a wavelength of 750 nm, the diffraction-limited angular resolution of the system is 0'.04; currently, the magnitude limit is V approximately 7 mag. At the distances of nearby open clusters, diffraction- limited images should resolve companions with separations as small as 4 - 6 AU - comparable to the Sun-Jupiter distance. The ability to study such close separations is critical, since most companions are expected to have separations in the few AU to tens of AU range. With the exceptional angular resolution of the current AEOS setup, but restricted target magnitude range, we are conducting a companion search of a large, well-defined sample of bright early-type stars in nearby open clusters and in the field. Our data set will both characterize this relatively new adaptive optics system and answer questions in binary star formation and stellar X- ray activity. We will discuss our experience using AEOS, the data analysis involved, and our initial results.

  3. Obtaining high resolution XUV coronal images

    NASA Technical Reports Server (NTRS)

    Golub, L.; Spiller, E.

    1992-01-01

    Photographs obtained during three flights of an 11 inch diameter normal incident soft X-ray (wavelength 63.5 A) telescope are analyzed and the data are compared to the results expected from tests of the mirror surfaces. Multilayer coated X ray telescopes have the potential for 0.01 arcsec resolution, and there is optimism that such high quality mirrors can be built. Some of the factors which enter into the performance actually achieved in practice are as follows: quality of the mirror substrate, quality of the multilayer coating, and number of photons collected. Measurements of multilayer mirrors show that the actual performance achieved in the solar X-ray images demonstrates a reduction in the scattering compared to that calculated from the topography of the top surface of the multilayer. In the brief duration of a rocket flight, the resolution is also limited by counting statistics from the number of photons collected. At X-ray Ultraviolet (XUV) wavelengths from 171 to 335 A the photon flux should be greater than 10(exp 10) ph/sec, so that a resolution better than 0.1 arcsec might be achieved, if mirror quality does not provide a limit first. In a satellite, a large collecting area will be needed for the highest resolution.

  4. High Resolution X-ray Imaging

    NASA Technical Reports Server (NTRS)

    Cash, Webster

    2002-01-01

    set of two major x-ray astronomy missions based on the concepts I developed and demonstrated under this SR&T grant. The first Maxim is to image the sky at 100 micro-arcsecond resolution. That is one thousand times higher resolution than Hubble. The full Maxim has the ultimate goal of imaging the event horizon of a black hole in an active galactic nucleus (ALAN). This will require 0.1 micro-arcsecond resolution - one million times higher than Hubble! Nonetheless, using the techniques developed under this grant, it has become possible. Maxim Pathfinder is now in the NASA planning for a new start in approximately 20 10. The full Maxim is carried as a vision mission for the post 2015 timeframe. Finally, this grant is the evolved version of the SR&T grant we carried during the 1980s and up to 1994. At that point in time this grant was also working on x-ray optics, but concentrating on x-ray spectroscopy. The techniques developed by 1990 were not chosen for use on Chandra or XMM-Newton because they were too new. During the last year, however, the Constellation-X mission recognized the need for better spectroscopy techniques and tapped our expertise. We were able to support the initial work on Con-X through this program. It now appears that the off-plane mount will be used in Con-X, increasing performance and decreasing cost and risk.

  5. Snapshots

    NASA Astrophysics Data System (ADS)

    Smorodinskaya, Noemi

    It may sound too trivial, but it is very important that life consists of details. It becomes still more important when you are trying to get together the recollections using the details you remember. Snapshots render memorable moments in imperfect images. This is exactly what is presented below viewed by an external observer...

  6. Snapshot retinal imaging Mueller matrix polarimeter

    NASA Astrophysics Data System (ADS)

    Wang, Yifan; Kudenov, Michael; Kashani, Amir; Schwiegerling, Jim; Escuti, Michael

    2015-09-01

    Early diagnosis of glaucoma, which is a leading cause for visual impairment, is critical for successful treatment. It has been shown that Imaging polarimetry has advantages in early detection of structural changes in the retina. Here, we theoretically and experimentally present a snapshot Mueller Matrix Polarimeter fundus camera, which has the potential to record the polarization-altering characteristics of retina with a single snapshot. It is made by incorporating polarization gratings into a fundus camera design. Complete Mueller Matrix data sets can be obtained by analyzing the polarization fringes projected onto the image plane. In this paper, we describe the experimental implementation of the snapshot retinal imaging Mueller matrix polarimeter (SRIMMP), highlight issues related to calibration, and provide preliminary images acquired from the camera.

  7. Wide swath and high resolution optical imaging satellite of Japan

    NASA Astrophysics Data System (ADS)

    Katayama, Haruyoshi; Kato, Eri; Imai, Hiroko; Sagisaka, Masakazu

    2016-05-01

    The "Advanced optical satellite" (tentative name) is a follow-on mission from ALOS. Mission objectives of the advanced optical satellite is to build upon the existing advanced techniques for global land observation using optical sensors, as well as to promote data utilization for social needs. Wide swath and high resolution optical imager onboard the advanced optical satellite will extend the capabilities of earlier ALOS missions. The optical imager will be able to collect high-resolution (< 1 m) and wide-swath (70 km) images with high geo-location accuracy. This paper introduces a conceptual design of the advanced optical satellite.

  8. High-resolution Urban Image Classification Using Extended Features

    SciTech Connect

    Vatsavai, Raju

    2011-01-01

    High-resolution image classification poses several challenges because the typical object size is much larger than the pixel resolution. Any given pixel (spectral features at that location) by itself is not a good indicator of the object it belongs to without looking at the broader spatial footprint. Therefore most modern machine learning approaches that are based on per-pixel spectral features are not very effective in high- resolution urban image classification. One way to overcome this problem is to extract features that exploit spatial contextual information. In this study, we evaluated several features in- cluding edge density, texture, and morphology. Several machine learning schemes were tested on the features extracted from a very high-resolution remote sensing image and results were presented.

  9. Applications of high-resolution remote sensing image data

    NASA Technical Reports Server (NTRS)

    Strome, W. M.; Leckie, D.; Miller, J.; Buxton, R.

    1990-01-01

    There are many situations in which the image resolution of satellite data is insufficient to provide the detail required for resource management and environmental monitoring. This paper will focus on applications of high-resolution (0.4 to 10 m) airborne multispectral and imaging spectrometer data acquired in Canada using the MEIS II multispectral line imager and the PMI imaging spectrometer. Applications discussed will include forestry, mapping, and geobotany.

  10. Texture analysis of high-resolution FLAIR images for TLE

    NASA Astrophysics Data System (ADS)

    Jafari-Khouzani, Kourosh; Soltanian-Zadeh, Hamid; Elisevich, Kost

    2005-04-01

    This paper presents a study of the texture information of high-resolution FLAIR images of the brain with the aim of determining the abnormality and consequently the candidacy of the hippocampus for temporal lobe epilepsy (TLE) surgery. Intensity and volume features of the hippocampus from FLAIR images of the brain have been previously shown to be useful in detecting the abnormal hippocampus in TLE. However, the small size of the hippocampus may limit the texture information. High-resolution FLAIR images show more details of the abnormal intensity variations of the hippocampi and therefore are more suitable for texture analysis. We study and compare the low and high-resolution FLAIR images of six epileptic patients. The hippocampi are segmented manually by an expert from T1-weighted MR images. Then the segmented regions are mapped on the corresponding FLAIR images for texture analysis. The 2-D wavelet transforms of the hippocampi are employed for feature extraction. We compare the ability of the texture features from regular and high-resolution FLAIR images to distinguish normal and abnormal hippocampi. Intracranial EEG results as well as surgery outcome are used as gold standard. The results show that the intensity variations of the hippocampus are related to the abnormalities in the TLE.

  11. High resolution ultraviolet imaging spectrometer for latent image analysis.

    PubMed

    Lyu, Hang; Liao, Ningfang; Li, Hongsong; Wu, Wenmin

    2016-03-21

    In this work, we present a close-range ultraviolet imaging spectrometer with high spatial resolution, and reasonably high spectral resolution. As the transmissive optical components cause chromatic aberration in the ultraviolet (UV) spectral range, an all-reflective imaging scheme is introduced to promote the image quality. The proposed instrument consists of an oscillating mirror, a Cassegrain objective, a Michelson structure, an Offner relay, and a UV enhanced CCD. The finished spectrometer has a spatial resolution of 29.30μm on the target plane; the spectral scope covers both near and middle UV band; and can obtain approximately 100 wavelength samples over the range of 240~370nm. The control computer coordinates all the components of the instrument and enables capturing a series of images, which can be reconstructed into an interferogram datacube. The datacube can be converted into a spectrum datacube, which contains spectral information of each pixel with many wavelength samples. A spectral calibration is carried out by using a high pressure mercury discharge lamp. A test run demonstrated that this interferometric configuration can obtain high resolution spectrum datacube. The pattern recognition algorithm is introduced to analyze the datacube and distinguish the latent traces from the base materials. This design is particularly good at identifying the latent traces in the application field of forensic imaging.

  12. A High Resolution X-Ray Imaging Devicm

    NASA Astrophysics Data System (ADS)

    Roehrig, Hans; Dallas, William J.; Ovitt, Theron W.; Lamoreaux, Richard D.; Vercillo, Richard; McNeill, Kevin M.

    1989-04-01

    This paper describes a high resolution x-ray imaging device, which is under development at the University of Arizona. It is sponsored by NIH for application in coronary angiography, but has also application in other x-ray imaging fields requi ing high spatial resolution, such as mammography and nondestructive tasting. It consists of a 6" diameter external modular sensor, coupled fiber optically to the input of a 6" proximity focussed image intensifier. The intensifier's output is coupled via 6 fiber optic tapers to 6 CCD's for readout. The tapers are joined at the large end to form a 6" by 6" coplanar fiber optic taper assembly. The electronics is designed to form a composite image out of the 6 individual images provided by the 6 CCD's and display the image in full resolution (1152 x 1152) on a high resolution physicians review console. The paper discusses the design considerations, the features, the major problems and some preliminary results.

  13. High-resolution Mueller matrix imaging polarimetry for understanding high-resolution optoelectronic modulators

    NASA Astrophysics Data System (ADS)

    Pezzaniti, J. Larry; Chipman, Russell A.

    1994-09-01

    A high resolution Mueller matrix imaging polarimetry test bed has been constructed and calibrated that has unique capabilities for characterizing optoelectronic devices, such as liquid crystal modulators, PLZT modulators, quantum well modulators, and surface emitting lasers. Similarly, the instrument can perform end-to-end measurements on optoelectronic systems including optical computers, interconnects, and correlators. It addresses, at the systems level, the need for incorporating polarimetric analysis and measurement techniques into the design, alignment, and testing of photonics technologies. The polarimeter maps the polarization altering characteristics of optical devices and optical systems, producing means of the retardance, the diattenuation, and the depolarization. The polarization mappings may be obtained across individual pixels or across large pixel arrays. The data sets provide a wealth of information not otherwise accessible for characterizing device uniformity, operating parameters, angular bandwidth, as well as identifying non-ideal polarization characteristics.

  14. Design of UAV high resolution image transmission system

    NASA Astrophysics Data System (ADS)

    Gao, Qiang; Ji, Ming; Pang, Lan; Jiang, Wen-tao; Fan, Pengcheng; Zhang, Xingcheng

    2017-02-01

    In order to solve the problem of the bandwidth limitation of the image transmission system on UAV, a scheme with image compression technology for mini UAV is proposed, based on the requirements of High-definition image transmission system of UAV. The video codec standard H.264 coding module and key technology was analyzed and studied for UAV area video communication. Based on the research of high-resolution image encoding and decoding technique and wireless transmit method, The high-resolution image transmission system was designed on architecture of Android and video codec chip; the constructed system was confirmed by experimentation in laboratory, the bit-rate could be controlled easily, QoS is stable, the low latency could meets most applied requirement not only for military use but also for industrial applications.

  15. Vehicle Detection and Classification from High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Abraham, L.; Sasikumar, M.

    2014-11-01

    In the past decades satellite imagery has been used successfully for weather forecasting, geographical and geological applications. Low resolution satellite images are sufficient for these sorts of applications. But the technological developments in the field of satellite imaging provide high resolution sensors which expands its field of application. Thus the High Resolution Satellite Imagery (HRSI) proved to be a suitable alternative to aerial photogrammetric data to provide a new data source for object detection. Since the traffic rates in developing countries are enormously increasing, vehicle detection from satellite data will be a better choice for automating such systems. In this work, a novel technique for vehicle detection from the images obtained from high resolution sensors is proposed. Though we are using high resolution images, vehicles are seen only as tiny spots, difficult to distinguish from the background. But we are able to obtain a detection rate not less than 0.9. Thereafter we classify the detected vehicles into cars and trucks and find the count of them.

  16. Practical Applications Using A High Resolution Infrared Imaging System

    NASA Astrophysics Data System (ADS)

    Baraniak, David W.

    1981-01-01

    Infrared imaging systems can be classified into three general categories, low resolution, medium resolution and high resolution. It is the purpose of this paper to highlight specific applications best suited to high resolution, television capatable, infrared data acquisition techniques. The data was collected from both ground loped andoaerial based mobile positions where the temperature differentials varied from 15 C to 25 C. Specific applications include scanning building complexes from the exterior using a ground based moving vehicle, scanning buildings, concrete bridge decks and terrain from the air using a helicopter and scanning building interiors using a mobile hand truck.

  17. High resolution imaging systems for spin-stabilized Probe spacecraft

    NASA Astrophysics Data System (ADS)

    Danielson, G. E.; Malin, M. C.; Delamere, W. A.

    1981-01-01

    A novel design for a high-resolution imaging system which includes on-board data editing and optical navigation, suggests high quality images can be acquired from spin-stabilized spacecraft oriented towards high velocity, short duration planetary missions ('Probes'). The approach to designing imaging systems requires that mission objectives be met within the physical and fiscal constraints imposed by the spacecraft and mission design. Severe constraints imposed on a Comet Halley probe (for example, 57 km/sec encounter velocity with a small, 10 km diameter, object) coupled with a great uncertainty in encounter time and distance, were overcome by innovative use of existing technology. Such designs suggest that 3-axis stabilization or nonspinning platforms are not necessary to acquire high resolution, high quality planetary images.

  18. High resolution SPM imaging of organic molecules with functionalized tips

    NASA Astrophysics Data System (ADS)

    Jelínek, Pavel

    2017-08-01

    One of the most remarkable and exciting achievements in the field of scanning probe microscopy (SPM) in the last years is the unprecedented sub-molecular resolution of both atomic and electronic structures of single molecules deposited on solid state surfaces. Despite its youth, the technique has already brought many new possibilities to perform different kinds of measurements, which cannot be accomplished by other techniques. This opens new perspectives in advanced characterization of physical and chemical processes and properties of molecular structures on surfaces. Here, we discuss the history and recent progress of the high resolution imaging with a functionalized probe by means of atomic force microscopy (AFM), scanning tunnelling microscopy (STM) and inelastic electron tunneling spectroscopy (IETS). We describe the mechanisms responsible for the high-resolution AFM, STM and IETS-STM contrast. The complexity of this technique requires new theoretical approaches, where a relaxation of the functionalized probe is considered. We emphasise the similarities of the mechanism driving high-resolution SPM with other imaging methods. We also summarise briefly significant achievements and progress in different branches. Finally we provide brief perspectives and remaining challenges of the further refinement of these high-resolution methods.

  19. High resolution multiplexed functional imaging in live embyros (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Xu, Dongli; Peng, Leilei

    2016-03-01

    Optical projection tomography (OPT) creates isotropic 3D imaging of tissue. Two approaches exist today: Wide-field OPT illuminates the entire sample and acquires projection images with a camera; Scanning-laser optical tomography (SLOT) generates the projection with a moving laser beam and point detector. SLOT has superior light collecting efficiency than wide-field optical tomography, making it ideal for tissue fluorescence imaging. Regardless the approach, traditional OPT has to compromise between the resolution and the depth of view. In traditional SLOT, the focused Gaussian beam diverges quickly from the focused plane, making it impossible to achieve high resolution imaging through a large volume specimen. We report using Bessel beam instead of Gaussian beam to perform SLOT. By illuminating samples with a narrow Bessel beam throughout an extended depth, high-resolution projection images can be measured in large volume. Under Bessel illumination, the projection image contains signal from annular-rings of the Bessel beam. Traditional inverse Radon transform of these projections will result in ringing artifacts in reconstructed imaging. Thus a modified 3D filtered back projection algorithm is developed to perform tomography reconstructing of Bessel-illuminated projection images. The resulting 3D imaging is free of artifact and achieved cellular resolution in extended sample volume. The system is applied to in-vivo imaging of transgenic Zebrafish embryos. Results prove Bessel SLOT a promising imaging method in development biology research.

  20. Adaptive optics with pupil tracking for high resolution retinal imaging.

    PubMed

    Sahin, Betul; Lamory, Barbara; Levecq, Xavier; Harms, Fabrice; Dainty, Chris

    2012-02-01

    Adaptive optics, when integrated into retinal imaging systems, compensates for rapidly changing ocular aberrations in real time and results in improved high resolution images that reveal the photoreceptor mosaic. Imaging the retina at high resolution has numerous potential medical applications, and yet for the development of commercial products that can be used in the clinic, the complexity and high cost of the present research systems have to be addressed. We present a new method to control the deformable mirror in real time based on pupil tracking measurements which uses the default camera for the alignment of the eye in the retinal imaging system and requires no extra cost or hardware. We also present the first experiments done with a compact adaptive optics flood illumination fundus camera where it was possible to compensate for the higher order aberrations of a moving model eye and in vivo in real time based on pupil tracking measurements, without the real time contribution of a wavefront sensor. As an outcome of this research, we showed that pupil tracking can be effectively used as a low cost and practical adaptive optics tool for high resolution retinal imaging because eye movements constitute an important part of the ocular wavefront dynamics.

  1. Adaptive optics with pupil tracking for high resolution retinal imaging

    PubMed Central

    Sahin, Betul; Lamory, Barbara; Levecq, Xavier; Harms, Fabrice; Dainty, Chris

    2012-01-01

    Adaptive optics, when integrated into retinal imaging systems, compensates for rapidly changing ocular aberrations in real time and results in improved high resolution images that reveal the photoreceptor mosaic. Imaging the retina at high resolution has numerous potential medical applications, and yet for the development of commercial products that can be used in the clinic, the complexity and high cost of the present research systems have to be addressed. We present a new method to control the deformable mirror in real time based on pupil tracking measurements which uses the default camera for the alignment of the eye in the retinal imaging system and requires no extra cost or hardware. We also present the first experiments done with a compact adaptive optics flood illumination fundus camera where it was possible to compensate for the higher order aberrations of a moving model eye and in vivo in real time based on pupil tracking measurements, without the real time contribution of a wavefront sensor. As an outcome of this research, we showed that pupil tracking can be effectively used as a low cost and practical adaptive optics tool for high resolution retinal imaging because eye movements constitute an important part of the ocular wavefront dynamics. PMID:22312577

  2. High-resolution imaging of globular cluster cores

    NASA Technical Reports Server (NTRS)

    Weir, N.; Piotto, G.; Djorgovski, S.

    1990-01-01

    An approach based on the maximum entropy method aimed at increasing angular resolution to study globular cluster cores is presented. To perform the image restoration the Gull-Skilling (1989) MEMSYS-3 code for maximum entropy reconstruction of arbitrary data sets was used. This software was recently applied to restoration of ESO images of the R136 object in the core of the 30 Doradus nebula. It was demonstrated that the software made it possible to restore an image at subpixel spatial scales which facilitates the detection of very high-resolution structure in the restored image.

  3. Compact and mobile high resolution PET brain imager

    DOEpatents

    Majewski, Stanislaw [Yorktown, VA; Proffitt, James [Newport News, VA

    2011-02-08

    A brain imager includes a compact ring-like static PET imager mounted in a helmet-like structure. When attached to a patient's head, the helmet-like brain imager maintains the relative head-to-imager geometry fixed through the whole imaging procedure. The brain imaging helmet contains radiation sensors and minimal front-end electronics. A flexible mechanical suspension/harness system supports the weight of the helmet thereby allowing for patient to have limited movements of the head during imaging scans. The compact ring-like PET imager enables very high resolution imaging of neurological brain functions, cancer, and effects of trauma using a rather simple mobile scanner with limited space needs for use and storage.

  4. Saturn - high-resolution filtered image of Enceladus

    NASA Technical Reports Server (NTRS)

    1981-01-01

    This high-resolution filtered image of Enceladus was made from several images obtained Aug. 25 by Voyager 2 from a range of 119,000 kilometers (74,000 miles). It shows further surface detail on this Saturnian moon (also viewed in the accompanying release P-23955C/BW, S-2-50, imaged about the same time). Enceladus is seen to resemble Jupiter's Galilean satellite Ganymede, which is, however, about 10 times larger. Faintly visible here in 'Saturnshine' is the hemisphere turned away from the sun. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.

  5. Multispectral high-resolution hologram generation using orthographic projection images

    NASA Astrophysics Data System (ADS)

    Muniraj, I.; Guo, C.; Sheridan, J. T.

    2016-08-01

    We present a new method of synthesizing a digital hologram of three-dimensional (3D) real-world objects from multiple orthographic projection images (OPI). A high-resolution multiple perspectives of 3D objects (i.e., two dimensional elemental image array) are captured under incoherent white light using synthetic aperture integral imaging (SAII) technique and their OPIs are obtained respectively. The reference beam is then multiplied with the corresponding OPI and integrated to form a Fourier hologram. Eventually, a modified phase retrieval algorithm (GS/HIO) is applied to reconstruct the hologram. The principle is validated experimentally and the results support the feasibility of the proposed method.

  6. Saturn - high-resolution filtered image of Enceladus

    NASA Technical Reports Server (NTRS)

    1981-01-01

    This high-resolution filtered image of Enceladus was made from several images obtained Aug. 25 by Voyager 2 from a range of 119,000 kilometers (74,000 miles). It shows further surface detail on this Saturnian moon (also viewed in the accompanying release P-23955C/BW, S-2-50, imaged about the same time). Enceladus is seen to resemble Jupiter's Galilean satellite Ganymede, which is, however, about 10 times larger. Faintly visible here in 'Saturnshine' is the hemisphere turned away from the sun. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.

  7. Next generation high resolution adaptive optics fundus imager

    NASA Astrophysics Data System (ADS)

    Fournier, P.; Erry, G. R. G.; Otten, L. J.; Larichev, A.; Irochnikov, N.

    2005-12-01

    The spatial resolution of retinal images is limited by the presence of static and time-varying aberrations present within the eye. An updated High Resolution Adaptive Optics Fundus Imager (HRAOFI) has been built based on the development from the first prototype unit. This entirely new unit was designed and fabricated to increase opto-mechanical integration and ease-of-use through a new user interface. Improved camera systems for the Shack-Hartmann sensor and for the scene image were implemented to enhance the image quality and the frequency of the Adaptive Optics (AO) control loop. An optimized illumination system that uses specific wavelength bands was applied to increase the specificity of the images. Sample images of clinical trials of retinas, taken with and without the system, are shown. Data on the performance of this system will be presented, demonstrating the ability to calculate near diffraction-limited images.

  8. Extraction and labeling high-resolution images from PDF documents

    NASA Astrophysics Data System (ADS)

    Chachra, Suchet K.; Xue, Zhiyun; Antani, Sameer; Demner-Fushman, Dina; Thoma, George R.

    2013-12-01

    Accuracy of content-based image retrieval is affected by image resolution among other factors. Higher resolution images enable extraction of image features that more accurately represent the image content. In order to improve the relevance of search results for our biomedical image search engine, Open-I, we have developed techniques to extract and label high-resolution versions of figures from biomedical articles supplied in the PDF format. Open-I uses the open-access subset of biomedical articles from the PubMed Central repository hosted by the National Library of Medicine. Articles are available in XML and in publisher supplied PDF formats. As these PDF documents contain little or no meta-data to identify the embedded images, the task includes labeling images according to their figure number in the article after they have been successfully extracted. For this purpose we use the labeled small size images provided with the XML web version of the article. This paper describes the image extraction process and two alternative approaches to perform image labeling that measure the similarity between two images based upon the image intensity projection on the coordinate axes and similarity based upon the normalized cross-correlation between the intensities of two images. Using image identification based on image intensity projection, we were able to achieve a precision of 92.84% and a recall of 82.18% in labeling of the extracted images.

  9. High resolution multiplexed functional imaging in live embryos (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Xu, Dongli; Zhou, Weibin; Peng, Leilei

    2017-02-01

    Fourier multiplexed fluorescence lifetime imaging (FmFLIM) scanning laser optical tomography (FmFLIM-SLOT) combines FmFLIM and Scanning laser optical tomography (SLOT) to perform multiplexed 3D FLIM imaging of live embryos. The system had demonstrate multiplexed functional imaging of zebrafish embryos genetically express Foster Resonant Energy Transfer (FRET) sensors. However, previous system has a 20 micron resolution because the focused Gaussian beam diverges quickly from the focused plane, makes it difficult to achieve high resolution imaging over a long projection depth. Here, we present a high-resolution FmFLIM-SLOT system with achromatic Bessel beam, which achieves 3 micron resolution in 3D deep tissue imaging. In Bessel-FmFLIM-SLOT, multiple laser excitation lines are firstly intensity modulated by a Michelson interferometer with a spinning polygon mirror optical delay line, which enables Fourier multiplexed multi-channel lifetime measurements. Then, a spatial light modulator and a prism are used to transform the modulated Gaussian laser beam to an achromatic Bessel beam. The achromatic Bessel beam scans across the whole specimen with equal angular intervals as sample rotated. After tomography reconstruction and the frequency domain lifetime analysis method, both the 3D intensity and lifetime image of multiple excitation-emission can be obtained. Using Bessel-FmFLIM-SLOT system, we performed cellular-resolution FLIM tomography imaging of live zebrafish embryo. Genetically expressed FRET sensors in these embryo will allow non-invasive observation of multiple biochemical processes in vivo.

  10. Providing Internet Access to High-Resolution Lunar Images

    NASA Technical Reports Server (NTRS)

    Plesea, Lucian

    2008-01-01

    The OnMoon server is a computer program that provides Internet access to high-resolution Lunar images, maps, and elevation data, all suitable for use in geographical information system (GIS) software for generating images, maps, and computational models of the Moon. The OnMoon server implements the Open Geospatial Consortium (OGC) Web Map Service (WMS) server protocol and supports Moon-specific extensions. Unlike other Internet map servers that provide Lunar data using an Earth coordinate system, the OnMoon server supports encoding of data in Moon-specific coordinate systems. The OnMoon server offers access to most of the available high-resolution Lunar image and elevation data. This server can generate image and map files in the tagged image file format (TIFF) or the Joint Photographic Experts Group (JPEG), 8- or 16-bit Portable Network Graphics (PNG), or Keyhole Markup Language (KML) format. Image control is provided by use of the OGC Style Layer Descriptor (SLD) protocol. Full-precision spectral arithmetic processing is also available, by use of a custom SLD extension. This server can dynamically add shaded relief based on the Lunar elevation to any image layer. This server also implements tiled WMS protocol and super-overlay KML for high-performance client application programs.

  11. Providing Internet Access to High-Resolution Mars Images

    NASA Technical Reports Server (NTRS)

    Plesea, Lucian

    2008-01-01

    The OnMars server is a computer program that provides Internet access to high-resolution Mars images, maps, and elevation data, all suitable for use in geographical information system (GIS) software for generating images, maps, and computational models of Mars. The OnMars server is an implementation of the Open Geospatial Consortium (OGC) Web Map Service (WMS) server. Unlike other Mars Internet map servers that provide Martian data using an Earth coordinate system, the OnMars WMS server supports encoding of data in Mars-specific coordinate systems. The OnMars server offers access to most of the available high-resolution Martian image and elevation data, including an 8-meter-per-pixel uncontrolled mosaic of most of the Mars Global Surveyor (MGS) Mars Observer Camera Narrow Angle (MOCNA) image collection, which is not available elsewhere. This server can generate image and map files in the tagged image file format (TIFF), Joint Photographic Experts Group (JPEG), 8- or 16-bit Portable Network Graphics (PNG), or Keyhole Markup Language (KML) format. Image control is provided by use of the OGC Style Layer Descriptor (SLD) protocol. The OnMars server also implements tiled WMS protocol and super-overlay KML for high-performance client application programs.

  12. Coregistration of high-resolution Mars orbital images

    NASA Astrophysics Data System (ADS)

    Sidiropoulos, Panagiotis; Muller, Jan-Peter

    2015-04-01

    The systematic orbital imaging of the Martian surface started 4 decades ago from NASA's Viking Orbiter 1 & 2 missions, which were launched in August 1975, and acquired orbital images of the planet between 1976 and 1980. The result of this reconnaissance was the first medium-resolution (i.e. ≤ 300m/pixel) global map of Mars, as well as a variety of high-resolution images (reaching up to 8m/pixel) of special regions of interest. Over the last two decades NASA has sent 3 more spacecraft with onboard instruments for high-resolution orbital imaging: Mars Global Surveyor (MGS) having onboard the Mars Orbital Camera - Narrow Angle (MOC-NA), Mars Odyssey having onboard the Thermal Emission Imaging System - Visual (THEMIS-VIS) and the Mars Reconnaissance Orbiter (MRO) having on board two distinct high-resolution cameras, Context Camera (CTX) and High-Resolution Imaging Science Experiment (HiRISE). Moreover, ESA has the multispectral High resolution Stereo Camera (HRSC) onboard ESA's Mars Express with resolution up to 12.5m since 2004. Overall, this set of cameras have acquired more than 400,000 high-resolution images, i.e. with resolution better than 100m and as fine as 25 cm/pixel. Notwithstanding the high spatial resolution of the available NASA orbital products, their accuracy of areo-referencing is often very poor. As a matter of fact, due to pointing inconsistencies, usually form errors in roll attitude, the acquired products may actually image areas tens of kilometers far away from the point that they are supposed to be looking at. On the other hand, since 2004, the ESA Mars Express has been acquiring stereo images through the High Resolution Stereo Camera (HRSC), with resolution that is usually 12.5-25 metres per pixel. The achieved coverage is more than 64% for images with resolution finer than 20 m/pixel, while for ~40% of Mars, Digital Terrain Models (DTMs) have been produced with are co-registered with MOLA [Gwinner et al., 2010]. The HRSC images and DTMs

  13. Thin polymer etalon arrays for high-resolution photoacoustic imaging

    PubMed Central

    Hou, Yang; Huang, Sheng-Wen; Ashkenazi, Shai; Witte, Russell; O’Donnell, Matthew

    2009-01-01

    Thin polymer etalons are demonstrated as high-frequency ultrasound sensors for three-dimensional (3-D) high-resolution photoacoustic imaging. The etalon, a Fabry-Perot optical resonator, consists of a thin polymer slab sandwiched between two gold layers. It is probed with a scanning continuous-wave (CW) laser for ultrasound array detection. Detection bandwidth of a 20-μm-diam array element exceeds 50 MHz, and the ultrasound sensitivity is comparable to polyvinylidene fluoride (PVDF) equivalents of similar size. In a typical photoacoustic imaging setup, a pulsed laser beam illuminates the imaging target, where optical energy is absorbed and acoustic waves are generated through the thermoelastic effect. An ultrasound detection array is formed by scanning the probing laser beam on the etalon surface in either a 1-D or a 2-D configuration, which produces 2-D or 3-D images, respectively. Axial and lateral resolutions have been demonstrated to be better than 20 μm. Detailed characterizations of the optical and acoustical properties of the etalon, as well as photoacoustic imaging results, suggest that thin polymer etalon arrays can be used as ultrasound detectors for 3-D high-resolution photoacoustic imaging applications. PMID:19123679

  14. High-resolution three-dimensional imaging radar

    NASA Technical Reports Server (NTRS)

    Cooper, Ken B. (Inventor); Chattopadhyay, Goutam (Inventor); Siegel, Peter H. (Inventor); Dengler, Robert J. (Inventor); Schlecht, Erich T. (Inventor); Mehdi, Imran (Inventor); Skalare, Anders J. (Inventor)

    2010-01-01

    A three-dimensional imaging radar operating at high frequency e.g., 670 GHz, is disclosed. The active target illumination inherent in radar solves the problem of low signal power and narrow-band detection by using submillimeter heterodyne mixer receivers. A submillimeter imaging radar may use low phase-noise synthesizers and a fast chirper to generate a frequency-modulated continuous-wave (FMCW) waveform. Three-dimensional images are generated through range information derived for each pixel scanned over a target. A peak finding algorithm may be used in processing for each pixel to differentiate material layers of the target. Improved focusing is achieved through a compensation signal sampled from a point source calibration target and applied to received signals from active targets prior to FFT-based range compression to extract and display high-resolution target images. Such an imaging radar has particular application in detecting concealed weapons or contraband.

  15. The High Resolution Imaging Instrument for HEAO-B

    NASA Technical Reports Server (NTRS)

    Kubierschky, K.; Austin, G. K.; Harrison, D. C.; Roy, A. G.

    1978-01-01

    The High Resolution Imaging Instrument for the HEAO-B X-ray Telescope satellite is designed to reproduce images of celestial X-ray sources in the range of 0.2 to 4.0 keV. It provides both imaging and temporal data. The basic detector is a two-stage microchannel plate with a crossed-grid charge detector. Preamplifiers, detector bias supplies, and some processing circuits are colocated with the detector. The remaining electronic circuits are located in a remote central electronic assembly. The processing system is designed for single-photon processing. The imaging data rate is limited to 100 data points per second. Non-imaging total-field count rate is acquired with a maximum dead time of 14 microseconds per event.

  16. High-resolution QWIP thermal imager for AFV upgrade

    NASA Astrophysics Data System (ADS)

    Dahlberg, Anders G. M.

    2004-08-01

    Following on the success of the BIRC clip on thermal imaging sight for the BILL Anti-Tank Missile System, which was in fact the world's first military QWIP based thermal imager, and which has been successfully delivered to the Swedish Army in serial quantities, several new QWIP-based products from FLIR Systems AB in Sweden are now under contract for defense customers worldwide. These include the new Forward Observation Systems for Norway and Sweden, Airborne Search & Rescue Systems, and a new clip on thermal imager for the Bofors RBS 70 Air Defense Missile System. The latest of these products is the development of a High Resolution QWIP Thermal Imager, LIRC, under contract for an upgrade of a number of Swedish CV9040C Armored Fighting Vehicles for Swedish Army International Operations. The paper will focus on the rationale behind the system selection, the development of the military qualified QWIP Thermal Imagers and the current status of the program.

  17. Digital watermarking scheme for extremely high-resolution printing images

    NASA Astrophysics Data System (ADS)

    Honjo, Yuji; Tanaka, Kiyoshi

    2002-04-01

    In this work, we propose a new digital watermarking scheme for extremely high-resolution printing images applicable to On-Demand Publishing (ODP) system. We designed our scheme by considering the following requirements: (i) high image quality, (ii) high security, and (iii) watermark immunity (robustness). In order to attain these requirements we employ the idea of Spread Spectrum (SS) watermarking technique in our scheme and modify it to be applicable to color (CMYK) binary printing images. Simulation results verified that we could embed a watermark spreading over the entire output image as a weak energy and still keep high image quality. Also the watermark could be robustly decoded by controlling some parameters even after some possible attacks by a third party.

  18. Live CLEM imaging to analyze nuclear structures at high resolution.

    PubMed

    Haraguchi, Tokuko; Osakada, Hiroko; Koujin, Takako

    2015-01-01

    Fluorescence microscopy (FM) and electron microscopy (EM) are powerful tools for observing molecular components in cells. FM can provide temporal information about cellular proteins and structures in living cells. EM provides nanometer resolution images of cellular structures in fixed cells. We have combined FM and EM to develop a new method of correlative light and electron microscopy (CLEM), called "Live CLEM." In this method, the dynamic behavior of specific molecules of interest is first observed in living cells using fluorescence microscopy (FM) and then cellular structures in the same cell are observed using electron microscopy (EM). Following image acquisition, FM and EM images are compared to enable the fluorescent images to be correlated with the high-resolution images of cellular structures obtained using EM. As this method enables analysis of dynamic events involving specific molecules of interest in the context of specific cellular structures at high resolution, it is useful for the study of nuclear structures including nuclear bodies. Here we describe Live CLEM that can be applied to the study of nuclear structures in mammalian cells.

  19. High-resolution electronic imaging system for schlieren recording

    NASA Astrophysics Data System (ADS)

    Honour, Joseph

    2001-04-01

    High speed Schlieren photography is a reliable means of visualizing small changes of refractive index resulting from density differences within a transparent media. Schlieren techniques are frequently used for investigating the aerodynamics of high velocity projectiles to confirm the formation of shock waves on leading edge surfaces so that optimum design performance can be achieved. Traditionally this type of investigation would have been undertaken using film cameras, however, improvements in image quality provided by the rapid development of intensified silicon based sensors and associated electronics has offered a reliable alternative, without the inherent difficulties in quantitative data extraction. The development of a high resolution sixteen image electronic camera system provides the researcher with versatile recording system that can be used to capture detailed image sequences at framing rates up to two hundred million pictures per second. The number of information points is maintained, irrespective of framing rate, making it ideal for recording the complexity of detail available from these sensitive Schlieren techniques. The high resolution images, which are displayed within twenty seconds of capture, flexibility of operation, and comprehensive analysis software provide fast reliable access to experimental data.

  20. High resolution three-dimensional prostate ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Li, Yinbo; Patil, Abhay; Hossack, John A.

    2006-03-01

    This work reports on the application of ultrasound elastography to prostate cancer detection using a high resolution three-dimensional (3D) ultrasound imaging system. The imaging was performed at a relatively high frequency (14 MHz), yielding very fine resolution that is optimal for prostate ultrasound imaging. The fine resolution achieved aids in locating smaller lesions than are normally detectable. Elasticity was measured with a quantitative and automatically controlled "Synthetic Digital Rectal Examination (SDRE)" wherein a smoothly increasing force was applied by injecting water, controlled by an electronic syringe pump, into a latex cover over the transrectal transducer. The lesion identified as stiffened tissue was visually enhanced by colorizing and superimposing it over the conventional B-mode image. Experimental results using a tissue-mimicking phantom demonstrated that the reconstruction accuracy of the I-Beam transducer resulted in less than 15% volumetric error. Thus, this high resolution 3D prostate elastography is possible and may provide reliable and accurate determination of the size and the location of cancers, which may result in improved specificity and sensitivity of cancer detection.

  1. High resolution ultrasound and photoacoustic imaging of single cells.

    PubMed

    Strohm, Eric M; Moore, Michael J; Kolios, Michael C

    2016-03-01

    High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level.

  2. A high resolution capacitive imaging sensor for manufacturing applications

    SciTech Connect

    Novak, J.L.; Wiczer, J.J.

    1990-09-06

    A high resolution capacitive image sensing technique for measuring edge and surface profiles during manufacturing processes has been invented. A prototype device utilizing this technique consists of two 0.020 in. (500 {mu}m) diameter electrodes fabricated on a printed circuit board with a 0.010 in. (250 {mu}m) gap between them. As the device is mechanically scanned over the workpiece, the spatial variations in the edge or surface to be measured interfere with an electric field imposed between the electrodes, altering the mutual capacitance. The sensor functions as a near field proximity sensor producing range images of surface imperfections. This sensor has been used in applications requiring a preview image of burrs on the edge of a machined part and other processes requiring an inspection image after automated deburring operations. 10 refs., 8 figs.

  3. High resolution ultrasound and photoacoustic imaging of single cells

    PubMed Central

    Strohm, Eric M.; Moore, Michael J.; Kolios, Michael C.

    2016-01-01

    High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level. PMID:27114911

  4. Very High Resolution Image of Icy Cliffs on Europa

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image, taken by the camera onboard NASA's Galileo spacecraft, is a very high resolution view of the Conamara Chaos region on Jupiter's moon Europa. It shows an area where icy plates have been broken apart and moved around laterally. The top of this image is dominated by corrugated plateaus ending in icy cliffs over a hundred meters (a few hundred feet) high. Debris piled at the base of the cliffs can be resolved down to blocks the size of a house. A fracture that runs horizontally across and just below the center of the Europa image is about the width of a freeway.

    North is to the top right of the image, and the sun illuminates the surface from the east. The image is centered at approximately 9 degrees north latitude and 274 degrees west longitude. The image covers an area approximately 1.7 kilometers by 4 kilometers (1 mile by 2.5 miles). The resolution is 9 meters (30 feet) per picture element. This image was taken on December 16, 1997 at a range of 900 kilometers (540 miles) by Galileo's solid state imaging system.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/ galileo.

  5. High Resolution Diffusion Tensor Imaging of Human Nerves in Forearm

    PubMed Central

    Zhou, Yuxiang; Narayana, Ponnada A; Kumaravel, Manickam; Athar, Parveen; Patel, Vipulkumar S; Sheikh, Kazim A

    2013-01-01

    Purpose To implement high resolution diffusion tensor imaging (DTI) for visualization and quantification of peripheral nerves in human forearm. Materials and Methods This HIPAA-compliant study was approved by our Institutional Review Board and written informed consent was obtained from all the study participants. Images were acquired with T1-and T2-weighted turbo spin echo with/without fat saturation, short tau inversion recovery (STIR). In addition, high spatial resolution (1.0 × 1.0 × 3.0 mm3) DTI sequence was optimized for clearly visualizing ulnar, superficial radial and median nerves in the forearm. Maps of the DTI derived indices, FA, mean diffusivity (MD), longitudinal diffusivity (λ//) and radial diffusivity (λ⊥) were generated. Results For the first time the three peripheral nerves, ulnar, superficial radial and median, were visualized unequivocally on high resolution DTI-derived maps. DTI delineated the forearm nerves more clearly than other sequences. Significant differences in the DTI-derived measures, FA, MD, λ// and λ⊥, were observed among the three nerves. A strong correlation between the nerve size derived from FA map and T2-weighted images was observed. Conclusions High spatial resolution DTI is superior in identifying and quantifying the median, ulnar and superficial radial nerves in human forearm. Consistent visualization of small nerves and nerve branches is possible with high spatial resolution DTI. These normative data could potentially help in identifying pathology in diseased nerves. PMID:24243801

  6. Unsupervised Feature Learning for High-Resolution Satellite Image Classification

    SciTech Connect

    Cheriyadat, Anil M

    2013-01-01

    The rich data provided by high-resolution satellite imagery allow us to directly model geospatial neighborhoods by understanding their spatial and structural patterns. In this paper we explore an unsupervised feature learning approach to model geospatial neighborhoods for classification purposes. While pixel and object based classification approaches are widely used for satellite image analysis, often these approaches exploit the high-fidelity image data in a limited way. In this paper we extract low-level features to characterize the local neighborhood patterns. We exploit the unlabeled feature measurements in a novel way to learn a set of basis functions to derive new features. The derived sparse feature representation obtained by encoding the measured features in terms of the learned basis function set yields superior classification performance. We applied our technique on two challenging image datasets: ORNL dataset representing one-meter spatial resolution satellite imagery representing five land-use categories and, UCMERCED dataset consisting of 21 different categories representing sub-meter resolution overhead imagery. Our results are highly promising and, in the case of UCMERCED dataset we outperform the best results obtained for this dataset. We show that our feature extraction and learning methods are highly effective in developing a detection system that can be used to automatically scan large-scale high-resolution satellite imagery for detecting large-facility.

  7. Limiting liability via high-resolution image processing

    NASA Astrophysics Data System (ADS)

    Greenwade, L. E.; Overlin, Trudy K.

    1997-01-01

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as 'evidence ready,' even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  8. High-resolution three-dimensional imaging with compress sensing

    NASA Astrophysics Data System (ADS)

    Wang, Jingyi; Ke, Jun

    2016-10-01

    LIDAR three-dimensional imaging technology have been used in many fields, such as military detection. However, LIDAR require extremely fast data acquisition speed. This makes the manufacture of detector array for LIDAR system is very difficult. To solve this problem, we consider using compress sensing which can greatly decrease the data acquisition and relax the requirement of a detection device. To use the compressive sensing idea, a spatial light modulator will be used to modulate the pulsed light source. Then a photodetector is used to receive the reflected light. A convex optimization problem is solved to reconstruct the 2D depth map of the object. To improve the resolution in transversal direction, we use multiframe image restoration technology. For each 2D piecewise-planar scene, we move the SLM half-pixel each time. Then the position where the modulated light illuminates will changed accordingly. We repeat moving the SLM to four different directions. Then we can get four low-resolution depth maps with different details of the same plane scene. If we use all of the measurements obtained by the subpixel movements, we can reconstruct a high-resolution depth map of the sense. A linear minimum-mean-square error algorithm is used for the reconstruction. By combining compress sensing and multiframe image restoration technology, we reduce the burden on data analyze and improve the efficiency of detection. More importantly, we obtain high-resolution depth maps of a 3D scene.

  9. Segmentation Based Fuzzy Classification of High Resolution Images

    NASA Astrophysics Data System (ADS)

    Rao, Mukund; Rao, Suryaprakash; Masser, Ian; Kasturirangan, K.

    images, we build a much needed bridge between the methodology domains of GIS and Image Analysis. The idea of having an integrated 'geographical information processing' environment is becoming much more realistic now that 'GIS' objects can be used for analysing an image and vice versa, new 'GIS' objects can be directly generated without ignoring the rich information environment of geographical concepts, relations and scales. In the above scenario, the main aim of this project is to assess whether object-oriented classification techniques would be more suitable for remote sensing images - specifically in the context of high resolution images. The paper basically examines potentials of classification techniques - especially segmentation based methods that is based on an object-semantics and that uses not only the spectral information but also the spatial characteristics; studies the integration of segmentation and fuzzy-classification to derive user-oriented information from the high resolution images and evaluates how such segmentation based classification compares with the more common pixel- based statistical technique. Segmentation based fuzzy classification is applied to high resolution images from IRS and for 1m images from satellites - especially to extract urban information.

  10. High-resolution MR imaging of the normal rotator cuff.

    PubMed

    Middleton, W D; Kneeland, J B; Carrera, G F; Cates, J D; Kellman, G M; Campagna, N G; Jesmanowicz, A; Froncisz, W; Hyde, J S

    1987-03-01

    The shoulders of six normal volunteers were imaged with high-resolution MR in the axial, sagittal, and coronal planes. An angled pair of counter-rotating current loop-gap resonators designed specifically for the shoulder was used as a local coil. All images were compared with corresponding cryomicrotome sections from cadaver shoulders. The rotator cuff was analyzed in detail. It appeared as a complex, heterogeneous band to tissue superficial to the humeral head. The areas of low signal intensity corresponded to the central tendons of the four rotator cuff muscles. These tendons could be distinguished from each other as well as from the intervening components of the cuff, which have a moderate intensity. We concluded that MR is capable of imaging the normal rotator cuff and of separating the various components. This may allow for improved precision in the diagnosis of rotator cuff disorders.

  11. Detection of Barchan Dunes in High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Azzaoui, M. A.; Adnani, M.; El Belrhiti, H.; Chaouki, I. E.; Masmoudi, C.

    2016-06-01

    Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction filters. Then, the second step proceeds to eliminate the parts of the image having a texture different from that of the barchans dunes. Using supervised learning, we tested a coarse to fine textural analysis based on Kolomogorov Smirnov test and Youden's J-statistic on co-occurrence matrix. As an output we obtained a mask that we used in the next step to reduce the search area. In the third step we used a gliding window on the mask and check SURF features with SVM to get barchans dunes candidates. Detected barchans dunes were considered as the fusion of overlapping candidates. The results of this approach were very satisfying in processing time and precision.

  12. High Resolution Energetic X-ray Imager (HREXI)

    NASA Astrophysics Data System (ADS)

    Grindlay, Jonathan

    We propose to design and build the first imaging hard X-ray detector system that incorporates 3D stacking of closely packed detector readouts in finely-spaced imaging arrays with their required data processing and control electronics. In virtually all imaging astronomical detectors, detector readout is done with flex connectors or connections that are not vertical but rather horizontal , requiring loss of focal plane area. For high resolution pixel detectors needed for high speed event-based X-ray imaging, from low energy applications (CMOS) with focusing X-ray telescopes, to hard X-ray applications with pixelated CZT for large area coded aperture telescopes, this new detector development offers great promise. We propose to extend our previous and current APRA supported ProtoEXIST program that has developed the first large area imaging CZT detectors and demonstrated their astrophysical capabilities on two successful balloon flight to a next generation High Resolution Energetic X-ray Imager (HREXI), which would incorporate microvia technology for the first time to connect the readout ASIC on each CZT crystal directly to its control and data processing system. This 3-dimensional stacking of detector and readout/control system means that large area (>2m2) imaging detector planes for a High Resolution Wide-field hard X-ray telescope can be built with initially greatly reduced detector gaps and ultimately with no gaps. This increases detector area, efficiency, and simplicity of detector integration. Thus higher sensitivity wide-field imagers will be possible at lower cost. HREXI will enable a post-Swift NASA mission such as the EREXS concept proposed to PCOS to be conducted as a future MIDEX mission. This mission would conduct a high resolution (<2 arcmin) , broad band (5 200 keV) hard X-ray survey of black holes on all scales with ~10X higher sensitivity than Swift. In the current era of Time Domain Astrophysics, such a survey capability, in conjunction with a n

  13. All-Optical Ultrasound Transducers for High Resolution Imaging

    NASA Astrophysics Data System (ADS)

    Sheaff, Clay Smith

    High frequency ultrasound (HFUS) has increasingly been used within the past few decades to provide high resolution (< 200 mum) imaging in medical applications such as endoluminal imaging, intravascular imaging, ophthalmology, and dermatology. The optical detection and generation of HFUS using thin films offers numerous advantages over traditional piezoelectric technology. Circumvention of an electronic interface with the device head is one of the most significant given the RF noise, crosstalk, and reduced capacitance that encumbers small-scale electronic transducers. Thin film Fabry-Perot interferometers - also known as etalons - are well suited for HFUS receivers on account of their high sensitivity, wide bandwidth, and ease of fabrication. In addition, thin films can be used to generate HFUS when irradiated with optical pulses - a method referred to as Thermoelastic Ultrasound Generation (TUG). By integrating a polyimide (PI) film for TUG into an etalon receiver, we have created for the first time an all-optical ultrasound transducer that is both thermally stable and capable of forming fully sampled 2-D imaging arrays of arbitrary configuration. Here we report (1) the design and fabrication of PI-etalon transducers; (2) an evaluation of their optical and acoustic performance parameters; (3) the ability to conduct high-resolution imaging with synthetic 2-D arrays of PI-etalon elements; and (4) work towards a fiber optic PI-etalon for in vivo use. Successful development of a fiber optic imager would provide a unique field-of-view thereby exposing an abundance of prospects for minimally-invasive analysis, diagnosis, and treatment of disease.

  14. High-resolution adaptive imaging with a single photodiode

    PubMed Central

    Soldevila, F.; Salvador-Balaguer, E.; Clemente, P.; Tajahuerce, E.; Lancis, J.

    2015-01-01

    During the past few years, the emergence of spatial light modulators operating at the tens of kHz has enabled new imaging modalities based on single-pixel photodetectors. The nature of single-pixel imaging enforces a reciprocal relationship between frame rate and image size. Compressive imaging methods allow images to be reconstructed from a number of projections that is only a fraction of the number of pixels. In microscopy, single-pixel imaging is capable of producing images with a moderate size of 128 × 128 pixels at frame rates under one Hz. Recently, there has been considerable interest in the development of advanced techniques for high-resolution real-time operation in applications such as biological microscopy. Here, we introduce an adaptive compressive technique based on wavelet trees within this framework. In our adaptive approach, the resolution of the projecting patterns remains deliberately small, which is crucial to avoid the demanding memory requirements of compressive sensing algorithms. At pattern projection rates of 22.7 kHz, our technique would enable to obtain 128 × 128 pixel images at frame rates around 3 Hz. In our experiments, we have demonstrated a cost-effective solution employing a commercial projection display. PMID:26382114

  15. High-Resolution Mars Camera Test Image of Moon (Infrared)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This crescent view of Earth's Moon in infrared wavelengths comes from a camera test by NASA's Mars Reconnaissance Orbiter spacecraft on its way to Mars. The mission's High Resolution Imaging Science Experiment camera took the image on Sept. 8, 2005, while at a distance of about 10 million kilometers (6 million miles) from the Moon. The dark feature on the right is Mare Crisium. From that distance, the Moon would appear as a star-like point of light to the unaided eye. The test verified the camera's focusing capability and provided an opportunity for calibration. The spacecraft's Context Camera and Optical Navigation Camera also performed as expected during the test.

    The Mars Reconnaissance Orbiter, launched on Aug. 12, 2005, is on course to reach Mars on March 10, 2006. After gradually adjusting the shape of its orbit for half a year, it will begin its primary science phase in November 2006. From the mission's planned science orbit about 300 kilometers (186 miles) above the surface of Mars, the high resolution camera will be able to discern features as small as one meter or yard across.

  16. High resolution 3D imaging of synchrotron generated microbeams

    SciTech Connect

    Gagliardi, Frank M.; Cornelius, Iwan; Blencowe, Anton; Franich, Rick D.; Geso, Moshi

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  17. Feature preserving compression of high resolution SAR images

    NASA Astrophysics Data System (ADS)

    Yang, Zhigao; Hu, Fuxiang; Sun, Tao; Qin, Qianqing

    2006-10-01

    Compression techniques are required to transmit the large amounts of high-resolution synthetic aperture radar (SAR) image data over the available channels. Common Image compression methods may lose detail and weak information in original images, especially at smoothness areas and edges with low contrast. This is known as "smoothing effect". It becomes difficult to extract and recognize some useful image features such as points and lines. We propose a new SAR image compression algorithm that can reduce the "smoothing effect" based on adaptive wavelet packet transform and feature-preserving rate allocation. For the reason that images should be modeled as non-stationary information resources, a SAR image is partitioned to overlapped blocks. Each overlapped block is then transformed by adaptive wavelet packet according to statistical features of different blocks. In quantifying and entropy coding of wavelet coefficients, we integrate feature-preserving technique. Experiments show that quality of our algorithm up to 16:1 compression ratio is improved significantly, and more weak information is reserved.

  18. Two simple image slicers for high resolution spectroscopy

    NASA Astrophysics Data System (ADS)

    Tala, M.; Vanzi, L.; Avila, G.; Guirao, C.; Pecchioli, E.; Zapata, A.; Pieralli, F.

    2017-01-01

    We present the design, manufacturing, test and performance of two image slicers for high resolution spectroscopy. Based on the classical Bowen-Walraven concept, our slicers allow to make two slices of the image of the input fibre. We introduce the idea of a second fibre that can be cropped in half to reach the same width of the science target fibre and that can be used for simultaneous wavelength reference. The slicers presented are mirror and prism based, respectively. Both devices work within expectation, showing differences mainly in their efficiency. The prism based slicer is the solution that was adopted for the FIDEOS spectrograph, an instrument built by the AIUC for the ESO 1m telescope of La Silla. Test spectra obtained with this instrument are included as examples of a real application of the device.

  19. Galileo at Io: results from high-resolution imaging.

    PubMed

    McEwen, A S; Belton, M J; Breneman, H H; Fagents, S A; Geissler, P; Greeley, R; Head, J W; Hoppa, G; Jaeger, W L; Johnson, T V; Keszthelyi, L; Klaasen, K P; Lopes-Gautier, R; Magee, K P; Milazzo, M P; Moore, J M; Pappalardo, R T; Phillips, C B; Radebaugh, J; Schubert, G; Schuster, P; Simonelli, D P; Sullivan, R; Thomas, P C; Turtle, E P; Williams, D A

    2000-05-19

    During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather than from the source of silicate lava (caldera or fissure, often with red pyroclastic deposits). Most of the active flows in equatorial regions are being emplaced slowly beneath insulated crust, but rapidly emplaced channelized flows are also found at all latitudes. There is no evidence for high-viscosity lava, but some bright flows may consist of sulfur rather than mafic silicates. The mountains, plateaus, and calderas are strongly influenced by tectonics and gravitational collapse. Sapping channels and scarps suggest that many portions of the upper approximately 1 kilometer are rich in volatiles.

  20. Optical diffraction tomography for high resolution live cell imaging.

    PubMed

    Sung, Yongjin; Choi, Wonshik; Fang-Yen, Christopher; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S

    2009-01-05

    We report the experimental implementation of optical diffraction tomography for quantitative 3D mapping of refractive index in live biological cells. Using a heterodyne Mach-Zehnder interferometer, we record complex field images of light transmitted through a sample with varying directions of illumination. To quantitatively reconstruct the 3D map of complex refractive index in live cells, we apply optical diffraction tomography based on the Rytov approximation. In this way, the effect of diffraction is taken into account in the reconstruction process and diffraction-free high resolution 3D images are obtained throughout the entire sample volume. The quantitative refractive index map can potentially serve as an intrinsic assay to provide the molecular concentrations without the addition of exogenous agents and also to provide a method for studying the light scattering properties of single cells.

  1. High-resolution imaging of solar system objects

    NASA Technical Reports Server (NTRS)

    Goldberg, Bruce A.

    1988-01-01

    The strategy of this investigation has been to develop new high-resolution imaging capabilities and to apply them to extended observing programs. These programs have included Io's neutral sodium cloud and comets. The Io observing program was carried out at Table Mountain Observatory (1976 to 1981), providing a framework interpreting Voyager measurements of the Io torus, and serving as an important reference for studying asymmetries and time variabilities in the Jovian magnetosphere. Comet observations made with the 3.6 m Canada-France-Hawaii Telescope and 1.6 m AMOS telescope (1984 to 1987) provide basis for studying early coma development in Halley, the kinematics of its nucleus, and the internal and external structure of the nucleus. Images of GZ from the ICE encounter period form the basis for unique comparisons with in situ magnetic field and dust impact measurements to determine the ion tail and dust coma structure, respectively.

  2. Galileo at Io: Results from High-Resolution Imaging

    NASA Astrophysics Data System (ADS)

    McEwen, A. S.; Belton, M. J. S.; Breneman, H. H.; Fagents, S. A.; Geissler, P.; Greeley, R.; Head, J. W.; Hoppa, G.; Jaeger, W. L.; Johnson, T. V.; Keszthelyi, L.; Klaasen, K. P.; Lopes-Gautier, R.; Magee, K. P.; Milazzo, M. P.; Moore, J. M.; Pappalardo, R. T.; Phillips, C. B.; Radebaugh, J.; Schubert, G.; Schuster, P.; Simonelli, D. P.; Sullivan, R.; Thomas, P. C.; Turtle, E. P.; Williams, D. A.

    2000-05-01

    During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather than from the source of silicate lava (caldera or fissure, often with red pyroclastic deposits). Most of the active flows in equatorial regions are being emplaced slowly beneath insulated crust, but rapidly emplaced channelized flows are also found at all latitudes. There is no evidence for high-viscosity lava, but some bright flows may consist of sulfur rather than mafic silicates. The mountains, plateaus, and calderas are strongly influenced by tectonics and gravitational collapse. Sapping channels and scarps suggest that many portions of the upper ~1 kilometer are rich in volatiles.

  3. Two simple image slicers for high resolution spectroscopy

    NASA Astrophysics Data System (ADS)

    Tala, M.; Vanzi, L.; Avila, G.; Guirao, C.; Pecchioli, E.; Zapata, A.; Pieralli, F.

    2017-04-01

    We present the design, manufacturing, test and performance of two image slicers for high resolution spectroscopy. Based on the classical Bowen-Walraven concept, our slicers allow to make two slices of the image of the input fibre. We introduce the idea of a second fibre that can be cropped in half to reach the same width of the science target fibre and that can be used for simultaneous wavelength reference. The slicers presented are mirror and prism based, respectively. Both devices work within expectation, showing differences mainly in their efficiency. The prism based slicer is the solution that was adopted for the FIDEOS spectrograph, an instrument built by the AIUC for the ESO 1m telescope of La Silla. Test spectra obtained with this instrument are included as examples of a real application of the device.

  4. High resolution microphotonic needle for endoscopic imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Tadayon, Mohammad Amin; Mohanty, Aseema; Roberts, Samantha P.; Barbosa, Felippe; Lipson, Michal

    2017-02-01

    GRIN (Graded index) lens have revolutionized micro endoscopy enabling deep tissue imaging with high resolution. The challenges of traditional GRIN lenses are their large size (when compared with the field of view) and their limited resolution. This is because of the relatively weak NA in standard graded index lenses. Here we introduce a novel micro-needle platform for endoscopy with much higher resolution than traditional GRIN lenses and a FOV that corresponds to the whole cross section of the needle. The platform is based on polymeric (SU-8) waveguide integrated with a microlens micro fabricated on a silicon substrate using a unique molding process. Due to the high index of refraction of the material the NA of the needle is much higher than traditional GRIN lenses. We tested the probe in a fluorescent dye solution (19.6 µM Alexa Flour 647 solution) and measured a numerical aperture of 0.25, focal length of about 175 µm and minimal spot size of about 1.6 µm. We show that the platform can image a sample with the field of view corresponding to the cross sectional area of the waveguide (80x100 µm2). The waveguide size can in principle be modified to vary size of the imaging field of view. This demonstration, combined with our previous work demonstrating our ability to implant the high NA needle in a live animal, shows that the proposed system can be used for deep tissue imaging with very high resolution and high field of view.

  5. High resolution reversible color images on photonic crystal substrates.

    PubMed

    Kang, Pilgyu; Ogunbo, Samuel O; Erickson, David

    2011-08-16

    When light is incident on a crystalline structure with appropriate periodicity, some colors will be preferentially reflected (Joannopoulos, J. D.; Meade, R. D.; Winn, J. N. Photonic crystals: molding the flow of light; Princeton University Press: Princeton, NJ, 1995; p ix, 137 pp). These photonic crystals and the structural color they generate represent an interesting method for creating reflective displays and drawing devices, since they can achieve a continuous color response and do not require back lighting (Joannopoulos, J. D.; Villeneuve, P. R.; Fan, S. H. Photonic crystals: Putting a new twist on light. Nature 1997, 386, 143-149; Graham-Rowe, D. Tunable structural colour. Nat. Photonics 2009, 3, 551-553.; Arsenault, A. C.; Puzzo, D. P.; Manners, I.; Ozin, G. A. Photonic-crystal full-colour displays. Nat. Photonics 2007, 1, 468-472; Walish, J. J.; Kang, Y.; Mickiewicz, R. A.; Thomas, E. L. Bioinspired Electrochemically Tunable Block Copolymer Full Color Pixels. Adv. Mater.2009, 21, 3078). Here we demonstrate a technique for creating erasable, high-resolution, color images using otherwise transparent inks on self-assembled photonic crystal substrates (Fudouzi, H.; Xia, Y. N. Colloidal crystals with tunable colors and their use as photonic papers. Langmuir 2003, 19, 9653-9660). Using inkjet printing, we show the ability to infuse fine droplets of silicone oils into the crystal, locally swelling it and changing the reflected color (Sirringhaus, H.; Kawase, T.; Friend, R. H.; Shimoda, T.; Inbasekaran, M.; Wu, W.; Woo, E. P. High-resolution inkjet printing of all-polymer transistor circuits. Science 2000, 290, 2123-2126). Multicolor images with resolutions as high as 200 μm are obtained from oils of different molecular weights with the lighter oils being able to penetrate deeper, yielding larger red shifts. Erasing of images is done simply by adding a low vapor pressure oil which dissolves the image, returning the substrate to its original state.

  6. High Resolution Imaging of Kepler Objects of Interest (KOI)

    NASA Astrophysics Data System (ADS)

    Dupree, Andrea K.; Adams, E.; Ciardi, D. R.; Gautier, T. N., III; Howell, S.; Kulesa, C.; McCarthy, D.; Kepler Science Team

    2011-05-01

    The spatial resolution of the Kepler telescope is designed to be 4 arcsec ( 1 pixel) which could allow background stars to contribute to the light of a Kepler target. Thus an observed transit might be a false positive due to a background eclipsing binary. In addition, dilution of the transit signal by a background star can severely compromise the parameters derived for a planet candidate. The Kepler Follow on Program (KFOP) includes high resolution images of the KOI targets, obtained principally at the following facilities: speckle imaging in V and R with the two-color speckle camera on the 3.5m WIYN telescope; Adaptive Optics imaging in J band and Ks with the PHARO near-infrared camera on the 200-in Hale Telescope; Adaptive Optics imaging in J and Ks band with the ARIES camera on the 6.5m MMT Telescope; AO imaging in J band and Ks with IRCAL on the 3-m telescope at Lick Observatory. Results from the follow up observations will be shown as well as the implications for the derivation of planetary characteristics. High spatial resolution images are a key part of the follow-up program for high-confidence level acceptance for Earth and super Earth-size planets.

  7. High resolution imaging of dynamic surface processes from the ISS

    NASA Astrophysics Data System (ADS)

    Donnellan, A.; Green, J. J.; De Jong, E. M.; Knight, R.; Bills, B.; Arrowsmith, R.

    Spaceborne persistent multi-angle imaging allows staring at selected targets during an orbit pass. From its vantage point on the International Space Station (ISS) a persistent Earth imaging telescope would provide hundreds of high-resolution images simultaneously. Observations could be in visible and SWIR bands as it stares at a scene of interest. These images provide rich multi-angle stereo views enabling understanding of rapidly changing Earth features with many applications to Earth science and disaster response. Current academic state-of-the-art is driven by single images taken with a near nadir view. Persistent imaging could address NASA's goal of understanding how and why the Earth's environment is changing, and could be used for forecasting and mitigating the effects of natural disasters. Specifically such a mission could be used to answer the questions: 1) How are Earth's vulnerable systems reflecting changes in climate? and 2) What processes and features characterize the magnitude and extent of disasters? A mission would meet geomorphologists' requirements observing changing features such as landslides, earthquakes, floods, volcanoes, and glaciers.

  8. Graph - Based High Resolution Satellite Image Segmentation for Object Recognition

    NASA Astrophysics Data System (ADS)

    Ravali, K.; Kumar, M. V. Ravi; Venugopala Rao, K.

    2014-11-01

    Object based image processing and analysis is challenging research in very high resolution satellite utilisation. Commonly ei ther pixel based classification or visual interpretation is used to recognize and delineate land cover categories. The pixel based classification techniques use rich spectral content of satellite images and fail to utilise spatial relations. To overcome th is drawback, traditional time consuming visual interpretation methods are being used operational ly for preparation of thematic maps. This paper addresses computational vision principles to object level image segmentation. In this study, computer vision algorithms are developed to define the boundary between two object regions and segmentation by representing image as graph. Image is represented as a graph G (V, E), where nodes belong to pixels and, edges (E) connect nodes belonging to neighbouring pixels. The transformed Mahalanobis distance has been used to define a weight function for partition of graph into components such that each component represents the region of land category. This implies that edges between two vertices in the same component have relatively low weights and edges between vertices in different components should have higher weights. The derived segments are categorised to different land cover using supervised classification. The paper presents the experimental results on real world multi-spectral remote sensing images of different landscapes such as Urban, agriculture and mixed land cover. Graph construction done in C program and list the run time for both graph construction and segmentation calculation on dual core Intel i7 system with 16 GB RAM, running 64bit window 7.

  9. High resolution imaging of objects located within a wall

    NASA Astrophysics Data System (ADS)

    Greneker, Eugene F.; Showman, Gregory A.; Trostel, John M.; Sylvester, Vincent

    2006-05-01

    Researchers at Georgia Tech Research Institute have developed a high resolution imaging radar technique that allows large sections of a test wall to be scanned in X and Y dimensions. The resulting images that can be obtained provide information on what is inside the wall, if anything. The scanning homodyne radar operates at a frequency of 24.1 GHz at with an output power level of approximately 10 milliwatts. An imaging technique that has been developed is currently being used to study the detection of toxic mold on the back surface of wallboard using radar as a sensor. The moisture that is associated with the mold can easily be detected. In addition to mold, the technique will image objects as small as a 4 millimeter sphere on the front or rear of the wallboard and will penetrate both sides of a wall made of studs and wallboard. Signal processing is performed on the resulting data to further sharpen the image. Photos of the scanner and images produced by the scanner are presented. A discussion of the signal processing and technical challenges are also discussed.

  10. Observing submesoscale currents from high resolution surface roughness images

    NASA Astrophysics Data System (ADS)

    Rascle, N.; Chapron, B.; Nouguier, F.; Mouche, A.; Ponte, A.

    2015-12-01

    At times, high resolution sea surface roughness variations can provide stunning details of submesoscale upper ocean dynamics. As interpreted, transformations of short scale wind waves by horizontal current gradients are responsible for those spectacular observations. Here we present tow major advances towards the quantitative interpretation of those observations. First, we show that surface roughness variations mainly trace two particular characteristics of the current gradient tensor, the divergence and the strain in the wind direction. Local vorticity and shear in the wind direction should not affect short scale roughness distribution and would not be detectable. Second, we discuss the effect of the viewing direction using sets of quasi-simultaneous sun glitter images, taken from different satellites to provide different viewing configurations. We show that upwind and crosswind viewing observations can be markedly different. As further confirmed with idealized numerical simulations, this anisotropy well traces surface current strain area, while more isotropic contrasts likely trace areas dominated by surface divergence conditions. These findings suggest the potential to directly observe surface currents at submesoscale by using high resolution roughness observations at multiple azimuth viewing angles.

  11. DTM modeling from remote sensing image with high resolution

    NASA Astrophysics Data System (ADS)

    Zhang, Jianqing; Zheng, Shunyi; Zhang, Yong

    2003-09-01

    Two key important techniques of DTM (Digital Terrain Model) modelling from remote sensing image pair with high resolution (RSIPHR) are introduced in this paper. First is determining conjugate point pair automatically by image matching. Because the approximate epipolar image pair of some RSIPHR remains quite large y-parallelx after relative registration, 2 D relaxation matching sh ould be used in the DTM Modeling. The procedure includes feature point extraction, approximate value estimation, matching and refining, check and filter. Second is the calculation of the spatial coordinates for the conjugate point pair from matching. For IKONS and QUICKBIRD images, it can be based on the RPC/RPB (Rational Polynomial Coefficients) parameters. Because the coordinate accuracy, computed by RPC/RPB parameters, is quite lower in many cases, a block adjustment with an affine transform of image coordinates should be completed based on some control points. Then, the affine transform and RPC/RPB parameters should be used in computation. If there are control points more than 4, the new, simple and strict geometric model based on affine transformation could be applied for any RSIPHR. Only 8 affine coefficients and one slantwise angle need to be determined by control points. Then, they can be applied in the computation.

  12. WFC3 UVIS High-resolution Imaging Performance

    NASA Astrophysics Data System (ADS)

    Gilliland, R. L.; Rajan, A.

    2011-01-01

    The sharp and stable point spread function of HST and WFC3 allows for the detection of stellar companions at small offsets from target stars. Deep images obtained through six UVIS filters are used to assess this ability to detect faint companions of brighter targets. Analogous capabilities from the ground make use of Adaptive Optics and Speckle imaging. We contrast the capabilities of HST/WFC3 with several existing AO systems for imaging of V 12 stars for which detection of faint companions as close as possible is desired, and to a delta-magnitude of 10. The observations under comparison are motivated by high-resolution imaging applications for the Kepler Mission to constrain the existence of fainter background stars which, if eclipsing binaries, could mimic transits. The HST/WFC3 observations are found to be superior in the comparisons made to Keck, MMT and Palomar AO and WIYN Speckle systems in terms of delta-magnitude limits outside of about 0.3 arcseconds. In a metric of fraction of phase space that can be probed for delta-magnitude to 10 companions out to 2 arcsecs the UVIS imaging out performs all other approaches by a factor > 5.

  13. High resolution imaging with impulse based thermoacoustic tomography

    NASA Astrophysics Data System (ADS)

    Kellnberger, Stephan; Hajiaboli, Amir; Sergiadis, George; Razansky, Daniel; Ntziachristos, Vasilis

    2011-07-01

    Existing imaging modalities like microwave- or radiofrequency (RF) induced thermoacoustic tomography systems show the potential for resolving structures deep inside tissue due to the high penetration properties of RF. However, one of the major drawbacks of existing thermoacoustic tomography systems with pulse modulated carrier frequency excitation is the compromise between efficient signal generation and attainable spatial resolution. In order to overcome limitations of conventional thermoacoustic imaging methods, we herein present and experimentally validate our novel approach towards high resolution thermoacoustic tomography. Instead of carrier-frequency amplification, we utilize ultrahigh-energy electromagnetic impulses at nanosecond duration with near-field energy coupling, thus maintaining thermoacoustic signal strength without compromising spatial resolution. Preliminary experiments on highly absorbing objects, consisting of copper wires with characteristic sizes of ~100 μm, reveal the resolution performance which yields 160 μm. Furthermore, benefits like its cost effectiveness, simplicity and compactness with the potential application in small animal imaging as well as human body imaging show that thermoacoustic tomography with impulse excitation is a promising imaging modality which has a broad range of applications.

  14. Ultrasound-aided high-resolution biophotonic imaging

    NASA Astrophysics Data System (ADS)

    Wang, Lihong V.

    2003-10-01

    We develop novel biophotonic imaging for early-cancer detection, a grand challenge in cancer research, using nonionizing electromagnetic and ultrasonic waves. Unlike ionizing x-ray radiation, nonionizing electromagnetic waves such as optical waves are safe for biomedical applications and reveal new contrast mechanisms and functional information. For example, our spectroscopic oblique-incidence reflectometry can detect skin cancers based on functional hemoglobin parameters and cell nuclear size with 95% accuracy. Unfortunately, electromagnetic waves in the nonionizing spectral region do not penetrate biological tissue in straight paths as do x-rays. Consequently, high-resolution tomography based on nonionizing electromagnetic waves alone, as demonstrated by our Mueller optical coherence tomography, is limited to superficial tissue imaging. Ultrasonic imaging, on the contrary, furnishes good imaging resolution but has poor contrast in early-stage tumors and has strong speckle artifacts as well. We developed ultrasound-mediated imaging modalities by combining electromagnetic and ultrasonic waves synergistically. The hybrid modalities yield speckle-free electromagnetic-contrast at ultrasonic resolution in relatively large biological tissue. In ultrasound-modulated (acousto)-optical tomography, a focused ultrasonic wave encodes diffuse laser light in scattering biological tissue. In photo-acoustic (thermo-acoustic) tomography, a low-energy laser (RF) pulse induces ultrasonic waves in biological tissue due to thermoelastic expansion.

  15. A mechanical microcompressor for high resolution imaging of motile specimens.

    PubMed

    Zinskie, Jessica A; Shribak, Michael; Bruist, Michael F; Aufderheide, Karl J; Janetopoulos, Chris

    2015-10-01

    In order to obtain fine details in 3 dimensions (3D) over time, it is critical for motile biological specimens to be appropriately immobilized. Of the many immobilization options available, the mechanical microcompressor offers many benefits. Our device, previously described, achieves gentle flattening of a cell, allowing us to image finely detailed structures of numerous organelles and physiological processes in living cells. We have imaged protozoa and other small metazoans using differential interference contrast (DIC) microscopy, orientation-independent (OI) DIC, and real-time birefringence imaging using a video-enhanced polychromatic polscope. We also describe an enhancement of our previous design by engineering a new device where the coverslip mount is fashioned onto the top of the base; so the entire apparatus is accessible on top of the stage. The new location allows for easier manipulation of the mount when compressing or releasing a specimen on an inverted microscope. Using this improved design, we imaged immobilized bacteria, yeast, paramecia, and nematode worms and obtained an unprecedented view of cell and specimen details. A variety of microscopic techniques were used to obtain high resolution images of static and dynamic cellular and physiological events. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Secure distribution for high resolution remote sensing images

    NASA Astrophysics Data System (ADS)

    Liu, Jin; Sun, Jing; Xu, Zheng Q.

    2010-09-01

    The use of remote sensing images collected by space platforms is becoming more and more widespread. The increasing value of space data and its use in critical scenarios call for adoption of proper security measures to protect these data against unauthorized access and fraudulent use. In this paper, based on the characteristics of remote sensing image data and application requirements on secure distribution, a secure distribution method is proposed, including users and regions classification, hierarchical control and keys generation, and multi-level encryption based on regions. The combination of the three parts can make that the same remote sensing images after multi-level encryption processing are distributed to different permission users through multicast, but different permission users can obtain different degree information after decryption through their own decryption keys. It well meets user access control and security needs in the process of high resolution remote sensing image distribution. The experimental results prove the effectiveness of the proposed method which is suitable for practical use in the secure transmission of remote sensing images including confidential information over internet.

  17. Wind measurements with the High Resolution Doppler Imager (HRDI)

    NASA Technical Reports Server (NTRS)

    Skinner, W. R.; Hays, P. B.; Abreu, V. J.

    1985-01-01

    The Upper Atmosphere Research Satellite (UARS), to be launched in 1989, is to provide a global data set required to understand the mechanisms controlling upper atmosphere structure and processes, as well as the response of the upper atmosphere to natural and human perturbations. The High Resolution Doppler Imager (HRDI) is the primary instrument for measuring the dynamics of the stratosphere and mesosphere. The goal of HRDI is to measure wind velocities in the stratosphere and mesosphere during the day and the mesosphere and thermosphere at night with an accuracy of 5 m/sec. HRDI will determine winds by measuring Doppler shifts of atmosphere absorption and emission features. Line of sight winds will be taken in two directions, thus allowing the wind vector to be formed. The HRDI instrument is overviewed. The basis of the measurement is explained, as is an outline of the instrument. Since neither instrument nor observational techniques is fully mature, only a brief sketch is presented.

  18. Imaging plasmodesmata with high-resolution scanning electron microscopy.

    PubMed

    Barton, Deborah A; Overall, Robyn L

    2015-01-01

    High-resolution scanning electron microscopy (HRSEM) is an effective tool to investigate the distribution of plasmodesmata within plant cell walls as well as to probe their complex, three-dimensional architecture. It is a useful alternative to traditional transmission electron microscopy (TEM) in which plasmodesmata are sectioned to reveal their internal substructures. Benefits of adopting an HRSEM approach to studies of plasmodesmata are that the specimen preparation methods are less complex and time consuming than for TEM, many plasmodesmata within a large region of tissue can be imaged in a single session, and three-dimensional information is readily available without the need for reconstructing TEM serial sections or employing transmission electron tomography, both of which are lengthy processes. Here we describe methods to prepare plant samples for HRSEM using pre- or postfixation extraction of cellular material in order to visualize plasmodesmata embedded within plant cell walls.

  19. Precision cosmology with time delay lenses: high resolution imaging requirements

    SciTech Connect

    Meng, Xiao-Lei; Liao, Kai; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Marshall, Philip J. E-mail: tt@astro.ucla.edu E-mail: mauger@ast.cam.ac.uk E-mail: dr.phil.marshall@gmail.com

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ''Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρ{sub tot}∝ r{sup −γ'} for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

  20. Precision cosmology with time delay lenses: High resolution imaging requirements

    SciTech Connect

    Meng, Xiao -Lei; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Liao, Kai; Marshall, Philip J.

    2015-09-28

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtot∝ r–γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. Furthermore, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

  1. Theme issue "High Resolution Earth Imaging for Geospatial Information"

    NASA Astrophysics Data System (ADS)

    Heipke, Christian; Soergel, Uwe; Rottensteiner, Franz; Jutzi, Boris

    2015-02-01

    Earth imaging from air and space has undergone major changes over the last decade. Examples of new and significant developments comprise the development and constant improvement of digital aerial cameras, multiple-echo and full-waveform laser scanners and the appearance of geosensor networks and unconventional platforms, most notably unmanned aircraft systems (UAS), sometimes called unmanned aerial vehicles (UAV) or remotely piloted aircraft systems (RPAS), and the ever increasing number of high-resolution and hyperspectral optical and SAR satellite sensors, small satellites and satellite constellations, which allow for both, a continued availability of satellite data over long periods of time, and a very short revisit time for any location on the globe. To give few examples: the latest Landsat satellite, appropriately called the Landsat data continuity mission or LDCM was launched on February 2013, continuing the Landsat mission which began back in 1972; during 2013 and 2014 France has put the SPOT 6 and 7 twin satellites into orbit, extending the history of high resolution space images, which started in 1986; and in April 2014 the European Space Agency (ESA) successfully launched the Sentinel 1A satellite with a synthetic aperture radar (SAR) sensor, the first of a fleet of different sensors that will be sent into space in the coming years. Sentinel 1A together with its twin system Sentinel 1B, to be launched in 2016, will continue the tremendous success story of ESA's C band SAR satellite activities dating back to 1991. Like the predecessors ERS 1, ERS 2, and Envisat ASAR, the Sentinel 1 systems are designed to cover the entire land mass with medium resolution, the repeat cycle is 12 days for Sentinel 1A alone and will even drop to six days as soon as both satellites are operational.

  2. Radiation length imaging with high-resolution telescopes

    NASA Astrophysics Data System (ADS)

    Stolzenberg, U.; Frey, A.; Schwenker, B.; Wieduwilt, P.; Marinas, C.; Lütticke, F.

    2017-02-01

    The construction of low mass vertex detectors with a high level of system integration is of great interest for next generation collider experiments. Radiation length images with a sufficient spatial resolution can be used to measure and disentangle complex radiation length X/X0 profiles and contribute to the understanding of vertex detector systems. Test beam experiments with multi GeV particle beams and high-resolution tracking telescopes provide an opportunity to obtain precise 2D images of the radiation length of thin planar objects. At the heart of the X/X0 imaging is a spatially resolved measurement of the scattering angles of particles traversing the object under study. The main challenges are the alignment of the reference telescope and the calibration of its angular resolution. In order to demonstrate the capabilities of X/X0 imaging, a test beam experiment has been conducted. The devices under test were two mechanical prototype modules of the Belle II vertex detector. A data sample of 100 million tracks at 4 GeV has been collected, which is sufficient to resolve complex material profiles on the 30 μm scale.

  3. Cortical Surface Reconstruction from High-Resolution MR Brain Images

    PubMed Central

    Osechinskiy, Sergey; Kruggel, Frithjof

    2012-01-01

    Reconstruction of the cerebral cortex from magnetic resonance (MR) images is an important step in quantitative analysis of the human brain structure, for example, in sulcal morphometry and in studies of cortical thickness. Existing cortical reconstruction approaches are typically optimized for standard resolution (~1 mm) data and are not directly applicable to higher resolution images. A new PDE-based method is presented for the automated cortical reconstruction that is computationally efficient and scales well with grid resolution, and thus is particularly suitable for high-resolution MR images with submillimeter voxel size. The method uses a mathematical model of a field in an inhomogeneous dielectric. This field mapping, similarly to a Laplacian mapping, has nice laminar properties in the cortical layer, and helps to identify the unresolved boundaries between cortical banks in narrow sulci. The pial cortical surface is reconstructed by advection along the field gradient as a geometric deformable model constrained by topology-preserving level set approach. The method's performance is illustrated on exvivo images with 0.25–0.35 mm isotropic voxels. The method is further evaluated by cross-comparison with results of the FreeSurfer software on standard resolution data sets from the OASIS database featuring pairs of repeated scans for 20 healthy young subjects. PMID:22481909

  4. Automatic Crowd Analysis from Very High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Sirmacek, B.; Reinartz, P.

    2011-04-01

    Recently automatic detection of people crowds from images became a very important research field, since it can provide crucial information especially for police departments and crisis management teams. Due to the importance of the topic, many researchers tried to solve this problem using street cameras. However, these cameras cannot be used to monitor very large outdoor public events. In order to bring a solution to the problem, herein we propose a novel approach to detect crowds automatically from remotely sensed images, and especially from very high resolution satellite images. To do so, we use a local feature based probabilistic framework. We extract local features from color components of the input image. In order to eliminate redundant local features coming from other objects in given scene, we apply a feature selection method. For feature selection purposes, we benefit from three different type of information; digital elevation model (DEM) of the region which is automatically generated using stereo satellite images, possible street segment which is obtained by segmentation, and shadow information. After eliminating redundant local features, remaining features are used to detect individual persons. Those local feature coordinates are also assumed as observations of the probability density function (pdf) of the crowds to be estimated. Using an adaptive kernel density estimation method, we estimate the corresponding pdf which gives us information about dense crowd and people locations. We test our algorithm usingWorldview-2 satellite images over Cairo and Munich cities. Besides, we also provide test results on airborne images for comparison of the detection accuracy. Our experimental results indicate the possible usage of the proposed approach in real-life mass events.

  5. Heuristic optimization in penumbral image for high resolution reconstructed image

    SciTech Connect

    Azuma, R.; Nozaki, S.; Fujioka, S.; Chen, Y. W.; Namihira, Y.

    2010-10-15

    Penumbral imaging is a technique which uses the fact that spatial information can be recovered from the shadow or penumbra that an unknown source casts through a simple large circular aperture. The size of the penumbral image on the detector can be mathematically determined as its aperture size, object size, and magnification. Conventional reconstruction methods are very sensitive to noise. On the other hand, the heuristic reconstruction method is very tolerant of noise. However, the aperture size influences the accuracy and resolution of the reconstructed image. In this article, we propose the optimization of the aperture size for the neutron penumbral imaging.

  6. Schiaparelli Crater Rim and Interior Deposits - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    A portion of the rim and interior of the large impact crater Schiaparelli is seen at high resolution in this image acquired October 18, 1997 by the Mars Global Surveyor Orbiter Camera (MOC). The area covered is very small--3.9 X 10.2 km (2.4 X 6.33 mi)--but is seen at 63 times higher resolution than the Viking image. The subdued relief and bright surface are attributed to blanketing by dust; many small craters have been completely filled in, and only the most recent (and very small) craters appear sharp and bowl-shaped. Some of the small craters are only 10-12 m (30-35 feet) across. Occasional dark streaks on steeper slopes are small debris slides that have probably occurred in the past few decades. The two prominent, narrow ridges in the center of the image may be related to the adjustment of the crater floor to age or the weight of the material filling the basin.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  7. Structure recognition from high resolution images of ceramic composites

    SciTech Connect

    Ushizima, Daniela; Perciano, Talita; Krishnan, Harinarayan; Loring, Burlen; Bale, Hrishikesh; Parkinson, Dilworth; Sethian, James

    2015-01-05

    Fibers provide exceptional strength-to-weight ratio capabilities when woven into ceramic composites, transforming them into materials with exceptional resistance to high temperature, and high strength combined with improved fracture toughness. Microcracks are inevitable when the material is under strain, which can be imaged using synchrotron X-ray computed micro-tomography (mu-CT) for assessment of material mechanical toughness variation. An important part of this analysis is to recognize fibrillar features. This paper presents algorithms for detecting and quantifying composite cracks and fiber breaks from high-resolution image stacks. First, we propose recognition algorithms to identify the different structures of the composite, including matrix cracks and fibers breaks. Second, we introduce our package F3D for fast filtering of large 3D imagery, implemented in OpenCL to take advantage of graphic cards. Results show that our algorithms automatically identify micro-damage and that the GPU-based implementation introduced here takes minutes, being 17x faster than similar tools on a typical image file.

  8. Spin resolved bandstructure imaging with a high resolution momentum microscope.

    PubMed

    Tusche, Christian; Krasyuk, Alexander; Kirschner, Jürgen

    2015-12-01

    We present a spin resolving "momentum microscope" for the high resolution imaging of the momentum distribution of photoelectrons. Measurements of the band structure of a Au(111) single crystal surface demonstrate an energy resolution of ΔE=12 meV and a momentum resolution of Δk∥=0.0049 Å(-1), measured at the line-width of the spin-orbit split Shockley surface state. The relative accuracy of the k∥ measurement in the order of 10(-4) Å(-1) reveals a deviation from the ideal two-dimensional free electron gas model of the Shockley surface state, manifested in a threefold radial symmetry. Spin resolution in the full momentum image is obtained by an imaging spin-filter based on low-energy electron diffraction at a Au passivated Ir(100) single crystal. Using working points at 10.5 eV and 11.5 eV scattering energy with a completely reversed asymmetry of ±60% we demonstrate the efficient mapping of the spin texture of the Au(111) surface state.

  9. High-resolution SIT TV tube for subnanosecond image shuttering

    NASA Astrophysics Data System (ADS)

    Yates, G. J.; Vine, B. H.; Aeby, I.; Dunbar, D. L.; King, N. S. P.; Jaramillo, S. A.; Thayer, N. N.; Noel, B. W.

    1984-09-01

    A new ultrafast high-resolution image shutter tube with reasonable gain and shuttering efficiency has been designed and tested. The design uses a grid-gated silicon-intensified-target (SIT) image section and a high-speed focus projection and scan (FPS) vidicon read-out section in one envelope to eliminate resolution losses from external coupling. The design features low-gate-interface capacity, a high-conductivity shutter grid, and a segmented low-resistivity photocathode for optimum gating speed. Optical gate widths as short as 400 ps + or - 100 ps for full shuttering of the 25-mm-diam input window with spatial resolution as high as 15 1p/mm have been measured. Some design criteria, most of the electrical and optical performance data for several variations in the basic design, and a comparison (of several key response functions) with similarly tested 18- and 25-mm-diam proximity-focused microchannel-plate (MCP) image intensifier tubes (MCPTs) are included.

  10. Cheetah: A high frame rate, high resolution SWIR image camera

    NASA Astrophysics Data System (ADS)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  11. High resolution myelin water imaging incorporating local tissue susceptibility analysis.

    PubMed

    Wu, Zhe; He, Hongjian; Sun, Yi; Du, Yiping; Zhong, Jianhui

    2017-10-01

    Quantitative myelin water imaging (MWI) from signal T2* decay acquired with multiple Gradient-Recalled Echo (mGRE) sequence has been widely used since its first report. A recent study showed that with low resolution data (2mm isotropic voxels), direct application of complex fitting to a three-pool WM model with frequency shift terms could produce more stable parameter estimation for myelin water fraction mapping. MWI maps of higher spatial resolution resulting in more detailed tissue structures and reduced partial volume effects around white matter/gray matter (WM/GM) interface, however, is more desirable. Furthermore, as signal-to-noise ratio (SNR) of original images decreases due to reduced voxel size, the direct complex fitting procedure of myelin water imaging becomes more prone to systematic errors which severely compromised stability and reliability of the result. Instead of using the original part of T2* decay, this work presents a new method based on the WM-induced phase from tissue susceptibility calculated with the same mGRE dataset, in a three-pool WM model (water of myelin, axonal and extracellular water), to improve high resolution MWI. Compared with direct complex fitting for the higher spatial resolution case, the proposed method is shown to provide a more stable and accurate estimation of MWI parameters, and finer details near WM/GM boundaries with greatly reduced partial volume effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. WINKLER - An imaging high resolution gamma-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Nakano, G. H.; Sandie, W. G.; Kilner, J. R.; Pang, F.; Imai, B. B.

    1991-04-01

    The WINKLER high-resolution gamma-ray spectrometer was originally developed to fly on a high-altitude aircraft. Following the discovery of Supernova 1987A in the Large Magellanic Cloud, arrangements were made to perform balloon-borne observations of this event. The instrument was quickly adapted to fit on a gondola furnished by NASA/MSFC in a collaborative effort and was flown in a series of three successful flights from Alice Springs, Australia. The second flight on October 29-31, 1987 resulted in the first high-resolution detection of the 847-keV line emission from the decay of 56Co and provided definitive confirmation of the explosive nucleosynthesis process. WINKLER comprises an array of nine coaxial n-type germanium detectors which are housed in a common vaccuum cryostat and surrounded by an NaI(Tl) scintillator shield that suppresses Compton interactions and gamma-ray background. Gamma-ray images are obtained with a rotational modulation collimator system attached to the spectrometer. Collimator holes in the upper section of the shield define the angular field of view of the instrument to 22 deg FWHM. The energy range of the spectrometer is 20 eV to 8 MeV, and the composite energy resolution from all detectors is 1.5 keV at 100 keV and about 2.5 keV at 1.33 MeV. The total frontal area of the sensor array is 214 cm2 with a volume of 1177 cm3, providing sufficient detection sensitivity for gamma-ray astronomy as well as for land-based applications such as treaty verification monitoring.

  13. NASA Releases New High-Resolution Earthrise Image

    NASA Image and Video Library

    2017-09-28

    must be rolled to the side (in this case 67 degrees), then the spacecraft slews with the direction of travel to maximize the width of the lunar horizon in LROC's Narrow Angle Camera image. All this takes place while LRO is traveling faster than 3,580 miles per hour (over 1,600 meters per second) relative to the lunar surface below the spacecraft! The high-resolution Narrow Angle Camera (NAC) on LRO takes black-and-white images, while the lower resolution Wide Angle Camera (WAC) takes color images, so you might wonder how we got a high-resolution picture of the Earth in color. Since the spacecraft, Earth, and moon are all in motion, we had to do some special processing to create an image that represents the view of the Earth and moon at one particular time. The final Earth image contains both WAC and NAC information. WAC provides the color, and the NAC provides high-resolution detail. "From the Earth, the daily moonrise and moonset are always inspiring moments," said Mark Robinson of Arizona State University in Tempe, principal investigator for LROC. "However, lunar astronauts will see something very different: viewed from the lunar surface, the Earth never rises or sets. Since the moon is tidally locked, Earth is always in the same spot above the horizon, varying only a small amount with the slight wobble of the moon. The Earth may not move across the 'sky', but the view is not static. Future astronauts will see the continents rotate in and out of view and the ever-changing pattern of clouds will always catch one's eye, at least on the nearside. The Earth is never visible from the farside; imagine a sky with no Earth or moon - what will farside explorers think with no Earth overhead?" NASA's first Earthrise image was taken with the Lunar Orbiter 1 spacecraft in 1966. Perhaps NASA's most iconic Earthrise photo was taken by the crew of the Apollo 8 mission as the spacecraft entered lunar orbit on Christmas Eve Dec. 24, 1968. That evening, the astronauts -- Commander

  14. Wide-Field-of-View, High-Resolution, Stereoscopic Imager

    NASA Technical Reports Server (NTRS)

    Prechtl, Eric F.; Sedwick, Raymond J.

    2010-01-01

    A device combines video feeds from multiple cameras to provide wide-field-of-view, high-resolution, stereoscopic video to the user. The prototype under development consists of two camera assemblies, one for each eye. One of these assemblies incorporates a mounting structure with multiple cameras attached at offset angles. The video signals from the cameras are fed to a central processing platform where each frame is color processed and mapped into a single contiguous wide-field-of-view image. Because the resolution of most display devices is typically smaller than the processed map, a cropped portion of the video feed is output to the display device. The positioning of the cropped window will likely be controlled through the use of a head tracking device, allowing the user to turn his or her head side-to-side or up and down to view different portions of the captured image. There are multiple options for the display of the stereoscopic image. The use of head mounted displays is one likely implementation. However, the use of 3D projection technologies is another potential technology under consideration, The technology can be adapted in a multitude of ways. The computing platform is scalable, such that the number, resolution, and sensitivity of the cameras can be leveraged to improve image resolution and field of view. Miniaturization efforts can be pursued to shrink the package down for better mobility. Power savings studies can be performed to enable unattended, remote sensing packages. Image compression and transmission technologies can be incorporated to enable an improved telepresence experience.

  15. Searching for novel biomarkers using high resolution diffusion tensor imaging.

    PubMed

    Yassa, Michael A

    2011-01-01

    Diffusion tensor imaging is capable of resolving large fiber bundles (e.g. the corpus callosum) and has been quite informative in understanding the overall structural connectivity of the brain. Recent data has shown that traditional resolution limitations can be exceeded in humans in vivo to submillimeter resolution. This chapter discusses these new techniques, and specific applications to small pathways such as the perforant path in the medial temporal lobe. High-resolution diffusion tensor imaging is a promising new tool that can be used to discover novel biomarkers for Alzheimer's disease and other disorders. It allows for a much more detailed investigation of brain white matter than previously possible, perhaps offering clues into the first signs of synaptic deterioration that may precede frank neuron loss. Although these methods are still in their infancy and many challenges have to be overcome before they can be used in a clinical fashion, results so far have been promising. Challenges and future directions are discussed in detail.

  16. High Resolution Thermal Infrared Imaging of NGC 6334 I

    NASA Astrophysics Data System (ADS)

    De Buizer, J. M.; Pina, R. K.; Telesco, C. M.

    2000-12-01

    NGC 6334 I is one of the northern-most sites of massive star formation in the 20 parsec long train of molecular clouds and HII regions known as NGC 6334. At the center of NGC 6334 I lies a bright, cometary UCHII region named NGC 6334 F. Recent observations of NGC 6334 F and its vicinity at mid-infrared wavelengths have revealed several separate sources (Persi et al. 1998, Kraemer et al. 1999). Furthermore, a new source has been detected at 7 mm by Carral et al. (1997) just west of NGC 6334 F. Here we present new mid-infrared images of the sources in this area acquired with OSCIR at the CTIO 4-m and the Keck II 10-m telescopes. These new high-resolution images, coupled with already existent data on outflow and distribution of molecular material, allow new insights into the nature of the sources in NGC 6334 I, and the roles that outflow and masers play in this region.

  17. High-resolution retinal imaging with micro adaptive optics system.

    PubMed

    Niu, Saisai; Shen, Jianxin; Liang, Chun; Zhang, Yunhai; Li, Bangming

    2011-08-01

    Based on the dynamic characteristics of human eye aberration, a microadaptive optics retina imaging system set is established for real-time wavefront measurement and correction. This paper analyzes the working principles of a 127-unit Hartmann-Shack wavefront sensor and a 37-channel micromachine membrane deformable mirror adopted in the system. The proposed system achieves wavefront reconstruction through the adaptive centroid detection method and the mode reconstruction algorithm of Zernike polynomials, so that human eye aberration can be measured accurately. Meanwhile, according to the adaptive optics aberration correction control model, a closed-loop iterative aberration correction algorithm based on Smith control is presented to realize efficient and real-time correction of human eye aberration with different characteristics, and characteristics of the time domain of the system are also optimized. According to the experiment results tested on a USAF 1951 standard resolution target and a living human retina (subject ZHY), the resolution of the system can reach 3.6 LP/mm, and the human eye wavefront aberration of 0.728λ (λ=785 nm) can be corrected to 0.081λ in root mean square (RMS) so as to achieve the diffraction limit (Strehl ratio is 0.866), then high-resolution retina images are obtained.

  18. ROSAT High Resolution Imager observations of PSR 0656 + 14

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.; Cordova, F. A.; Pavlov, G. G.; Robinson, C. R.; Thompson, R. J., Jr.

    1993-01-01

    We have used the High Resolution Imager (HRI) on ROSAT to image PSR 0656 + 14 at soft X-ray energies. With a net observing time of 10,326 s, we obtained a source event rate of 0.382 +/- 0.007 counts/s. Comparing the radial distribution of these counts between 15 and 100 arcsec to an empirically derived point spread function for HRI soft sources, we find no evidence of a spatially extended X-ray nebula to a limiting surface brightness of 1.67 x 10 exp -6 counts/s/sq arcsec, corresponding to a limit of 14 percent of the observed flux out to a radius of 100 arcsec. The X-ray emission of the pulsar is pulsed at the 0.385 s period of the radio pulsar, with a pulse fraction of 7 +/- 2.2 percent and a FWHM of 0.10 s. We discuss some models of the X-ray radiation of PSR 0656 + 14 compatible with both the HRI and PSPC results.

  19. High resolution imaging system for Udaipur Solar Observatory

    NASA Astrophysics Data System (ADS)

    Bayanna, A. Raja; Louis, Rohan Eugene; Kumar, Brajesh; Mathew, Shibu K.; Venkatakrishnan, P.

    2007-09-01

    A Multi-Application Solar Telescope (MAST) is proposed to be installed at the Udaipur Solar Observatory (USO) in India to monitor the Sun in optical and near infra-red wavelengths. The median value of the Fried's parameter at this site is 4 cm. USO is in the process of building an Adaptive optics (AO) system in order to have diffraction limited performance of the MAST under this moderate seeing condition. AO helps in achieving high-resolution imaging by compensating the atmospheric turbulence in real-time. We have performed simulations to evaluate the performance of AO for various seeing conditions. It was concluded that with the present availability of AO system components, a 55 cm aperture telescope would yield optimum performance with AO, in combination with post-processing techniques like speckle imaging and phase diversity. At present, we are developing a proto-type AO system at USO to demonstrate its performance with a 15 cm Coudé refracting telescope as a preparation for the main AO system to be deployed on the MAST. The prototype AO system is being realized in two phases. In the first phase, we have developed an image stabilization system to compensate the global tilt of the wave-front. The second phase consists of sensing and correcting the local tilts of the wave-front by integrating a micro-machined membrane deformable mirror with the image stabilization system and is currently in progress. Here, we present the details of our proto-type AO system. We also present preliminary results obtained from simulations using Phase Diversity as a post processing technique.

  20. High resolution imaging of the outflow channels on Mars

    NASA Astrophysics Data System (ADS)

    Davatzes, A. K.; Gulick, V. C.

    2008-12-01

    We report observations of the outflow channels on Mars from HiRISE images in MRO's first Martian year. Several hundred images of the outflow channels on Mars have been collected to date from HiRISE, as well as coordinated images with CTX and CRISM. Depositional features, such as slackwater deposits and small bedforms that are expected to be visible at the resolution of HiRISE have not yet been observed, largely due to post-fluvial modification of the channels. Many of the channels have been subsequently covered by a thin layer of lava, ash, dust, or lineated valley fill. Although altered slightly by later aeolian modification, Ares Valles and Kasei Valles preserve much of the original fluvial erosional forms, particularly cataracts and longitudinal grooves that can be used to infer the mechanics of the flow. Cataracts, steep knickpoints in the large outflow channels, were once large waterfalls on the Martian surface. These have been observed in all of the larger outflow systems, including Kasai, Athabasca, Mangala, and Reull Valles. High resolution imaging shows that all of the cataract systems have multiple generations of erosion, with smaller subchannels within the cataract system. Based on the length of the recession and the morphological evidence most of the large channels experienced multiple flooding events or pulses. The tectonically sourced outflow channels, such as Athabasca and Mangala Valles, show sourcing at regions of complex fault geometries, specifically at fault relays. In terrestrial systems, relays tend to be regions of concentrated stress that can produce dilation manifested as high joint density, as well as point sources for hydrothermal outflow on Earth. Athabasca and Mangala Valles, sourced proximal to large volcanic centers, may have been regions of major hydrothermal activity in the past.

  1. High Resolution 3D Radar Imaging of Comet Interiors

    NASA Astrophysics Data System (ADS)

    Asphaug, E. I.; Gim, Y.; Belton, M.; Brophy, J.; Weissman, P. R.; Heggy, E.

    2012-12-01

    Knowing the interiors of comets and other primitive bodies is fundamental to our understanding of how planets formed. We have developed a Discovery-class mission formulation, Comet Radar Explorer (CORE), based on the use of previously flown planetary radar sounding techniques, with the goal of obtaining high resolution 3D images of the interior of a small primitive body. We focus on the Jupiter-Family Comets (JFCs) as these are among the most primitive bodies reachable by spacecraft. Scattered in from far beyond Neptune, they are ultimate targets of a cryogenic sample return mission according to the Decadal Survey. Other suitable targets include primitive NEOs, Main Belt Comets, and Jupiter Trojans. The approach is optimal for small icy bodies ~3-20 km diameter with spin periods faster than about 12 hours, since (a) navigation is relatively easy, (b) radar penetration is global for decameter wavelengths, and (c) repeated overlapping ground tracks are obtained. The science mission can be as short as ~1 month for a fast-rotating JFC. Bodies smaller than ~1 km can be globally imaged, but the navigation solutions are less accurate and the relative resolution is coarse. Larger comets are more interesting, but radar signal is unlikely to be reflected from depths greater than ~10 km. So, JFCs are excellent targets for a variety of reasons. We furthermore focus on the use of Solar Electric Propulsion (SEP) to rendezvous shortly after the comet's perihelion. This approach leaves us with ample power for science operations under dormant conditions beyond ~2-3 AU. This leads to a natural mission approach of distant observation, followed by closer inspection, terminated by a dedicated radar mapping orbit. Radar reflections are obtained from a polar orbit about the icy nucleus, which spins underneath. Echoes are obtained from a sounder operating at dual frequencies 5 and 15 MHz, with 1 and 10 MHz bandwidths respectively. The dense network of echoes is used to obtain global 3D

  2. High Resolution Image Reconstruction from Projection of Low Resolution Images DIffering in Subpixel Shifts

    NASA Technical Reports Server (NTRS)

    Mareboyana, Manohar; Le Moigne-Stewart, Jacqueline; Bennett, Jerome

    2016-01-01

    In this paper, we demonstrate a simple algorithm that projects low resolution (LR) images differing in subpixel shifts on a high resolution (HR) also called super resolution (SR) grid. The algorithm is very effective in accuracy as well as time efficiency. A number of spatial interpolation techniques using nearest neighbor, inverse-distance weighted averages, Radial Basis Functions (RBF) etc. used in projection yield comparable results. For best accuracy of reconstructing SR image by a factor of two requires four LR images differing in four independent subpixel shifts. The algorithm has two steps: i) registration of low resolution images and (ii) shifting the low resolution images to align with reference image and projecting them on high resolution grid based on the shifts of each low resolution image using different interpolation techniques. Experiments are conducted by simulating low resolution images by subpixel shifts and subsampling of original high resolution image and the reconstructing the high resolution images from the simulated low resolution images. The results of accuracy of reconstruction are compared by using mean squared error measure between original high resolution image and reconstructed image. The algorithm was tested on remote sensing images and found to outperform previously proposed techniques such as Iterative Back Projection algorithm (IBP), Maximum Likelihood (ML), and Maximum a posterior (MAP) algorithms. The algorithm is robust and is not overly sensitive to the registration inaccuracies.

  3. High-Resolution Imaging of Asteroids/Satellites with AO

    NASA Astrophysics Data System (ADS)

    Merline, William

    2012-02-01

    We propose to make high-resolution observations of asteroids using AO, to measure size, shape, and pole position (spin vectors), and/or to search for satellites. We have demonstrated that AO imaging allows determination of the pole/dimensions in 1 or 2 nights on a single target, rather than the years of observations with lightcurve inversion techniques that only yield poles and axial ratios, not true dimensions. Our new technique (KOALA) combines AO imaging with lightcurve and occultation data for optimum size/shape determinations. We request that LGS be available for faint targets, but using NGS AO, we will measure several large and intermediate asteroids that are favorably placed in spring/summer of 2012 for size/shape/pole. Accurately determining the volume from the often-irregular shape allows us to derive densities to much greater precision in cases where the mass is known, e.g., from the presence of a satellite. We will search several d! ozen asteroids for the presence of satellites, particularly in under-studied populations, particularly NEOs (we have recently achieved the first-ever optical image of an NEO binary [Merline et al. 2008b, IAUC 8977]). Satellites provide a real-life lab for testing collisional models. We will search for satellites around special objects at the request of lightcurve observers, and we will make a search for debris in the vicinity of Pluto, in support of the New Horizons mission. Our shape/size work requires observations over most of a full rotation period (typically several hours).

  4. A Stretching Device for High Resolution Live-Cell Imaging

    PubMed Central

    Huang, Lawrence; Mathieu, Pattie S.; Helmke, Brian P.

    2012-01-01

    Several custom-built and commercially available devices are available to investigate cellular responses to substrate strain. However, analysis of structural dynamics by microscopy in living cells during stretch is not readily feasible. We describe a novel stretch device optimized for high-resolution live-cell imaging. The unit assembles onto standard inverted microscopes and applies constant magnitude or cyclic stretch at physiological magnitudes to cultured cells on elastic membranes. Interchangeable modular indenters enable delivery of equibiaxial and uniaxial stretch profiles. Strain analysis performed by tracking fluorescent microspheres adhered onto the substrate demonstrated reproducible application of stretch profiles. In endothelial cells transiently expressing EGFP-vimentin and paxillin-DsRed2 and subjected to constant magnitude equibiaxial stretch, the 2-D strain tensor demonstrated efficient transmission through the extracellular matrix and focal adhesions. Decreased transmission to the intermediate filament network was measured, and a heterogeneous spatial distribution of maximum stretch magnitude revealed discrete sites of strain focusing. Spatial correlation of vimentin and paxillin displacement vectors provided an estimate of the extent of mechanical coupling between the structures. Interestingly, switching the spatial profile of substrate strain reveals that actin-mediated edge ruffling is not desensitized to repeated mechano-stimulation. These initial observations show that the stretch device is compatible with live-cell microscopy and is a novel tool for measuring dynamic structural remodeling under mechanical strain. PMID:20195762

  5. Coded aperture subreflector array for high resolution radar imaging

    NASA Astrophysics Data System (ADS)

    Lynch, Jonathan J.; Herrault, Florian; Kona, Keerti; Virbila, Gabriel; McGuire, Chuck; Wetzel, Mike; Fung, Helen; Prophet, Eric

    2017-05-01

    HRL Laboratories has been developing a new approach for high resolution radar imaging on stationary platforms. High angular resolution is achieved by operating at 235 GHz and using a scalable tile phased array architecture that has the potential to realize thousands of elements at an affordable cost. HRL utilizes aperture coding techniques to minimize the size and complexity of the RF electronics needed for beamforming, and wafer level fabrication and integration allow tiles containing 1024 elements to be manufactured with reasonable costs. This paper describes the results of an initial feasibility study for HRL's Coded Aperture Subreflector Array (CASA) approach for a 1024 element micromachined antenna array with integrated single-bit phase shifters. Two candidate electronic device technologies were evaluated over the 170 - 260 GHz range, GaN HEMT transistors and GaAs Schottky diodes. Array structures utilizing silicon micromachining and die bonding were evaluated for etch and alignment accuracy. Finally, the overall array efficiency was estimated to be about 37% (not including spillover losses) using full wave array simulations and measured device performance, which is a reasonable value at 235 GHz. Based on the measured data we selected GaN HEMT devices operated passively with 0V drain bias due to their extremely low DC power dissipation.

  6. Special issue on high-resolution optical imaging

    NASA Astrophysics Data System (ADS)

    Smith, Peter J. S.; Davis, Ilan; Galbraith, Catherine G.; Stemmer, Andreas

    2013-09-01

    The pace of development in the field of advanced microscopy is truly breath-taking, and is leading to major breakthroughs in our understanding of molecular machines and cell function. This special issue of Journal of Optics draws attention to a number of interesting approaches, ranging from fluorescence and imaging of unlabelled cells, to computational methods, all of which are describing the ever increasing detail of the dynamic behaviour of molecules in the living cell. This is a field which traditionally, and currently, demonstrates a marvellous interplay between the disciplines of physics, chemistry and biology, where apparent boundaries to resolution dissolve and living cells are viewed in ever more clarity. It is fertile ground for those interested in optics and non-conventional imaging to contribute high-impact outputs in the fields of cell biology and biomedicine. The series of articles presented here has been selected to demonstrate this interdisciplinarity and to encourage all those with a background in the physical sciences to 'dip their toes' into the exciting and dynamic discoveries surrounding cell function. Although single molecule super-resolution microscopy is commercially available, specimen preparation and interpretation of single molecule data remain a major challenge for scientists wanting to adopt the techniques. The paper by Allen and Davidson [1] provides a much needed detailed introduction to the practical aspects of stochastic optical reconstruction microscopy, including sample preparation, image acquisition and image analysis, as well as a brief description of the different variants of single molecule localization microscopy. Since super-resolution microscopy is no longer restricted to three-dimensional imaging of fixed samples, the review by Fiolka [2] is a timely introduction to techniques that have been successfully applied to four-dimensional live cell super-resolution microscopy. The combination of multiple high-resolution techniques

  7. Thoracic Sarcoidosis: Imaging with High Resolution Computed Tomography

    PubMed Central

    Singh, Sarvinder; Jain, Megha; Singh, Satyendra Narayan; Sharma, Rajat Kumar

    2017-01-01

    Introduction Sarcoidosis is a disease of unknown aetiology that primarily affects the lungs. Clinical and radiological findings with demonstration of non caseating granulomas on pathology is utilised for diagnosing the disease. Aim To assess and evaluate the features of thoracic sarcoidosis on High Resolution Computed Tomography (HRCT) chest. Materials and Methods A total of 40 (31 males and 9 females) cases of pulmonary sarcoidosis in a period of three years were included in this study. Patients underwent detailed clinical evaluation, imaging, Pulmonary Function Tests (PFT) and pathological confirmation of disease. Chest radiograph was obtained in all patients. HRCT was done on 16 slice Computed Tomography (CT) using 1 mm slice thickness and high spatial frequency algorithm for image re-construction. Images were viewed and evaluated using appropriate lung and mediastinal windows. The lymph nodes were classified as hilar and mediastinal with Maximum Short Axis Diameter (MSAD) more than 10 mm taken as cut-off for enlargement. Pulmonary opacities were classified as nodules (micronodules 1-4 mm and macronodules >5 mm), reticular opacities, fibrotic lesions, ground glass opacities and consolidations. Nodule distribution classified as perilymphatic centrilobular and random. Repeat scanning done on follow up or as clinically indicated. Results A total of five patients had Stage I disease, 24 patients had Stage II disease, eight patients had Stage III disease and three patients had stage IV disease. Mediastinal lymphdenopathy present in 29 patients. Bilateral hilar adenopathy was the predominant pattern seen in 22 patients. Lung parenchymal lesions excluding end stage disease noted in 32 patients. The characteristic HRCT lung parenchymal involvement of micronodules with a perilymphatic distribution was seen in 26 patients. HRCT features of predominant upper and middle lobe distribution seen in majority of patients. Documented atypical lesions and the characteristic

  8. Polarization disks in near-infrared high-resolution imaging

    NASA Astrophysics Data System (ADS)

    Murakawa, K.

    2010-07-01

    A polarization disk is a characteristic feature of optical and near-infrared (NIR) polarimetric images of young stellar objects (YSOs) and is regarded as convincing evidence that a dust disk is present. We analyze high-resolution linear polarization maps of a sample of low-mass YSO disk models by means of radiative transfer calculations to investigate the effects of the disk geometry and grain sizes on polarization properties. Our modeling assumes spherical grains with a power-law size distribution of n(a)∝ a-3.5; 0.005 μm ≤ a ≤ a_max and with a fixed a_max of 0.25 μm for the outer envelope and a different a_max for the disk. The parameters to examine are the disk height (i.e. the ratio of the disk height to the outer disk radius H of 0.1 to 1.0) and the dust sizes in the disk (i.e. a_max of 0.25 to 1000.0 μm). In a near pole-on view, the polarization vectors are centro-symmetrically aligned even towards the disk, but the degree of polarization can be different from the envelope. We predict that the pole-on disk can be distinguished from the envelope. In contrast, the model images show a bipolar nebulosity and a polarization disk with a vector alignment in edge-on view. The polarization is low (<10%) for large grains or low H values and high (up to ~80%) for small grains and high H values. In contrast, comparably constant polarizations (20-40%) are obtained in the optical. The wavelength dependence in low NIR polarization cases is often detected in many T Tauri stars, suggesting that grain growth or an advanced disk accretion is expected in these objects. The opposite trend in high NIR polarization cases, which is found in some low-mass protostars, is reproduced with spherical grain models. To understand our results, we developed a generalized scattering model, which is an extension of the vector alignment mechanism. In the low-mass star disk case, multiple-scattered light behaves as if it chooses paths of comparably low optical density region (e.g. the

  9. High Resolution Seismic Imaging of the Brawley Seismic Fault Zone

    NASA Astrophysics Data System (ADS)

    Goldman, M.; Catchings, R. D.; Rymer, M. J.; Lohman, R. B.; McGuire, J. J.; Sickler, R. R.; Criley, C.; Rosa, C.

    2011-12-01

    In March 2010, we acquired a series of high-resolution P-wave seismic reflection and refraction data sets across faults in the Brawley seismic zone (BSZ) within the Salton Sea Geothermal Field (SSGF). Our objectives were to determine the dip, possible structural complexities, and seismic velocities within the BSZ. One dataset was 3.4 km long trending east-west, and consisted of 334 shots recorded by a 2.4 km spread of 40 hz geophones placed every 10 meters. The spread was initially laid out from the first station at the eastern end of the profile to roughly 2/3 into the profile. After about half the shots, the spread was shifted from roughly 1/3 into the profile to the last station at the western end of the profile. P-waves were generated by Betsy-Seisgun 'shots' spaced every 10 meters. Initial analysis of first breaks indicate near-surface velocities of ~500-600 meters/sec, and deeper velocities of around 2000 meters/sec. Preliminary investigation of shot gathers indicate a prominent fault that extends to the ground surface. This fault is on a projection of the Kalin fault from about 40 m to the south, and broke the surface down to the west with an approximately north-south strike during a local swarm of earthquakes in 2005 and also slipped at the surface in association with the 2010 El Mayor-Cucapah earthquake in Baja California. The dataset is part of the combined Obsidian Creep data set, and provides the most detailed, publicly available subsurface images of fault structures in the BSZ and SSGF.

  10. [High resolution diffusion-weighted imaging for characterising nasopharyngeal carcinoma].

    PubMed

    Wang, Y; Wang, G J; Ye, Y; Lu, Y T; Wu, W H; Li, S L

    2017-05-09

    Objective: To evaluate the characteristics of high resolution diffusion-weighted imaging(DWI) using readout segmentation of long variable echo trains (RESOLVE ) for nasopharyngeal carcinoma (NPC). Methods: A total of 131 with newly diagnosed NPC patients from the 5th Affiliated Hospital of Sun Yat-sen University were included in this study from October 2013 to April 2016.DWI using RESOLVE technique was performed. The signal intensity (SI(lesion)), and mean(ADC(mean)), maximum(ADC(max)), minimum (ADC(min))ADCs of NPC were calculated. The signal intensity (SI(normal))and ADC (ADC(normal))of normal nasopharyngeal tissue were calculated. These quantitative parameters of NPC and normal nasopharyngeal tissue were compared.Statistical difference of ADC(mean), ADC(max) and ADC(min) between the clinical tumor stages were assessed. Results: On the DWI, all NPCs were clearly shown as high signal intensity relative to the surrounding normal nasopharyngeal structure(F=70.019, P=0.000). The ADC(mean)(F=20.442, P=0.000), ADC(max)(F=35.374, P=0.000), ADC(min)(F=61.534, P=0.000) in the carcinoma were significantly lower compared with that of normal nasopharyngeal structure. There was no statistically significant difference of ADC(mean), ADC(max) and ADC(min) (P>0.05)in different clinical stages of NPC. Conclusion: NPC can be clearly detected by RESOLVE-DWI, but the ADC(mean), ADC(max) and ADC(min) can not be used for differentiating the clinical stage of NPC.

  11. High resolution Ceres HAMO atlas derived from Dawn FC images

    NASA Astrophysics Data System (ADS)

    Roatsch, Thomas; Kersten, Elke; Matz, Klaus-Dieter; Preusker, Frank; Scholten, Frank; Jaumann, Ralf; Raymond, Carol A.; Russell, Chris T.

    2016-04-01

    Introduction: NASA's Dawn spacecraft entered the orbit of dwarf planet Ceres in March 2015, and will characterize the geology, elemental and mineralogical composition, topography, shape, and internal structure of Ceres. One of the major goals of the mission is a global mapping of Ceres. Data: The Dawn mission was mapping Ceres in HAMO (High Altitude Mapping Orbit, 1475 km altitude) between August and October 2015. The framing camera took about 2,600 clear filter images with a resolution of about 140 m/pixel during these cycles. The images were taken with different viewing angles and different illumination conditions. We selected images from one cycle (cycle #1) for the mosaicking process to have similar viewing and illumination conditions. Very minor gaps in the coverage were filled with a few images from cycle #2. Data Processing: The first step of the processing chain towards the cartographic products is to ortho-rectify the images to the proper scale and map projec-tion type. This process requires detailed information of the Dawn orbit and attitude data and of the topography of the targets. Both, improved orientation and a high-resolution shape model, are provided by stereo processing (bundle block adjustment) of the HAMO stereo image dataset [3]. Ceres's HAMO shape model was used for the calculation of the ray intersection points while the map projection itself was done onto the reference sphere of Ceres with a radius of 470 km. The final step is the controlled mosaicking) of all images to a global mosaic of Ceres, the so-called basemap. Ceres map tiles: The Ceres atlas was produced in a scale of 1:750,000 and consists of 15 tiles that conform to the quadrangle scheme proposed by Greeley and Batson [4]. A map scale of 1:750,000 guarantees a mapping at the highest available Dawn resolution in HAMO. The individual tiles were extracted from the global mosaic and reprojected. Nomenclature: The Dawn team proposed 81 names for geological features. By international

  12. High resolution reconstruction of solar prominence images observed by the New Vacuum Solar Telescope

    NASA Astrophysics Data System (ADS)

    Xiang, Yong-yuan; Liu, Zhong; Jin, Zhen-yu

    2016-11-01

    A high resolution image showing fine structures is crucial for understanding the nature of solar prominence. In this paper, high resolution imaging of solar prominence on the New Vacuum Solar Telescope (NVST) is introduced, using speckle masking. Each step of the data reduction especially the image alignment is discussed. Accurate alignment of all frames and the non-isoplanatic calibration of each image are the keys for a successful reconstruction. Reconstructed high resolution images from NVST also indicate that under normal seeing condition, it is feasible to carry out high resolution observations of solar prominence by a ground-based solar telescope, even in the absence of adaptive optics.

  13. Snapshot imaging polarimeters using spatial modulation

    NASA Astrophysics Data System (ADS)

    Luo, Haitao

    The recent demonstration of a novel snapshot imaging polarimeter using the fringe modulation technique shows a promise in building a compact and moving-parts-free device. As just demonstrated in principle, this technique has not been adequately studied. In the effort of advancing this technique, we build a complete theory framework that can address the key issues regarding the polarization aberrations caused by using the functional elements. With this model, we can have the necessary knowledge in designing, analyzing and optimizing the systems. Also, we propose a broader technique that uses arbitrary modulation instead of sinusoidal fringes, which can give us more engineering freedom and can be the solution of achromatizing the system. In the hardware aspect, several important progresses are made. We extend the polarimeter technique from visible to middle wavelength infrared by using the yttrium vanadate crystals. Also, we incorporate a Savart Plate polarimter into a fundus camera to measure the human eye's retinal retardance, useful information for glaucoma diagnosis. Thirdly, a world-smallest imaging polarimeter is proposed and demonstrated, which may open many applications in security, remote sensing and bioscience.

  14. High resolution VESTA LAMO atlas derived from Dawn FC images.

    NASA Astrophysics Data System (ADS)

    Roatsch, Thomas; Kersten, Elke; Matz, Klaus-Dieter; Preusker, Frank; Scholten, Frank; Jaumann, Ralf; Raymond, Carol A.; Russell, Cris T.

    2013-04-01

    Introduction: NASA's Dawn spacecraft entered orbit of the inner main belt asteroid 4 Vesta on July 16, 2011, and spent about one year in orbit to characterize the geology, elemental and mineralogical composition, topography, shape, and internal structure of Vesta before it departed to asteroid 1 Ceres in late 2012. One of the major goals of the mission was a global mapping of Vesta. Data: The DAWN mission was mapping Vesta from three different orbit heights during Survey orbit (3100 km altitude), HAMO (High Altitude Mapping Orbit, 700 km altitude), and LAMO (Low Altitude Mapping Orbit, 210 km altitude) [1]. The Dawn mission is equipped with a framing camera (FC) [2] which was the prime instrument during the LAMO phase. DAWN orbited Vesta during LAMO in 21 cycles between December 2011 and end of April 2012. The framing camera took about 10,000 clear filter images with a resolution of about 20 m/pixel during these cycles. The images were taken with different viewing angles and different illumination conditions. We selected about 8,000 images for the global coverage of Vesta. Data Processing: The first step of the processing chain is to ortho rectify the images to the proper scale and map projection type. This process requires detailed high-resolution information of the local topography of Vesta. The global topgraphy was calculated during the stereo processing of the HAMO images [3] and was used here. The shape model was used for the calculation of the ray intersection points while the map projection itself was done onto a sphere with a mean radius of 255 km. The next step was the mosaicking of all images to one global mosaic of Vesta, the so called basemap. Vesta map tiles: The Vesta atlas was produced in a scale of 1:200,000 and consists of 30 tiles that conform to the quadrangle scheme proposed by Greeley and Batson [4] and is used for example for mapping Mars in a scale of 1:5,000,000. A map scale of 1:200,000 guarantees a mapping at the highest available DAWN

  15. High-Resolution Snapshots of Proteasome Inhibitors in Action Revise Inhibition Paradigms and Inspire Next-Generation Inhibitor Design.

    PubMed

    Carmony, Kimberly; Lee, Wooin; Kim, Kyung Bo

    2016-11-17

    New high-resolution crystal structures reported by Schrader and colleagues refine our understanding of how peptide epoxyketone anticancer drugs inactivate their target: the human proteasome. These findings provide important clues for the design of next-generation proteasome inhibitor drugs. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. A VLSI Processor Design of Real-Time Data Compression for High-Resolution Imaging Radar

    NASA Technical Reports Server (NTRS)

    Fang, W.

    1994-01-01

    For the high-resolution imaging radar systems, real-time data compression of raw imaging data is required to accomplish the science requirements and satisfy the given communication and storage constraints. The Block Adaptive Quantizer (BAQ) algorithm and its associated VLSI processor design have been developed to provide a real-time data compressor for high-resolution imaging radar systems.

  17. Parallel image registration method for snapshot Fourier transform imaging spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Zhu, Shuaishuai; Lin, Jie; Zhu, Feijia; Jin, Peng

    2017-08-01

    A fast and precise registration method for multi-image snapshot Fourier transform imaging spectroscopy is proposed. This method accomplishes registration of an image array using the positional relationship between homologous points in the subimages, which are obtained offline by preregistration. Through the preregistration process, the registration problem is converted to the problem of using a registration matrix to interpolate subimages. Therefore, the hardware interpolation of graphics processing unit (GPU) texture memory, which has speed advantages for its parallel computing, can be used to significantly enhance computational efficiency. Compared to a central processing unit, GPU performance showed ˜27 times acceleration in registration efficiency.

  18. An integral design strategy combining optical system and image processing to obtain high resolution images

    NASA Astrophysics Data System (ADS)

    Wang, Jiaoyang; Wang, Lin; Yang, Ying; Gong, Rui; Shao, Xiaopeng; Liang, Chao; Xu, Jun

    2016-05-01

    In this paper, an integral design that combines optical system with image processing is introduced to obtain high resolution images, and the performance is evaluated and demonstrated. Traditional imaging methods often separate the two technical procedures of optical system design and imaging processing, resulting in the failures in efficient cooperation between the optical and digital elements. Therefore, an innovative approach is presented to combine the merit function during optical design together with the constraint conditions of image processing algorithms. Specifically, an optical imaging system with low resolution is designed to collect the image signals which are indispensable for imaging processing, while the ultimate goal is to obtain high resolution images from the final system. In order to optimize the global performance, the optimization function of ZEMAX software is utilized and the number of optimization cycles is controlled. Then Wiener filter algorithm is adopted to process the image simulation and mean squared error (MSE) is taken as evaluation criterion. The results show that, although the optical figures of merit for the optical imaging systems is not the best, it can provide image signals that are more suitable for image processing. In conclusion. The integral design of optical system and image processing can search out the overall optimal solution which is missed by the traditional design methods. Especially, when designing some complex optical system, this integral design strategy has obvious advantages to simplify structure and reduce cost, as well as to gain high resolution images simultaneously, which has a promising perspective of industrial application.

  19. Snapshot spectral and polarimetric imaging; target identification with multispectral video

    NASA Astrophysics Data System (ADS)

    Bartlett, Brent D.; Rodriguez, Mikel D.

    2013-05-01

    As the number of pixels continue to grow in consumer and scientific imaging devices, it has become feasible to collect the incident light field. In this paper, an imaging device developed around light field imaging is used to collect multispectral and polarimetric imagery in a snapshot fashion. The sensor is described and a video data set is shown highlighting the advantage of snapshot spectral imaging. Several novel computer vision approaches are applied to the video cubes to perform scene characterization and target identification. It is shown how the addition of spectral and polarimetric data to the video stream allows for multi-target identification and tracking not possible with traditional RGB video collection.

  20. High-Resolution Views of Io's Emakong Patera: Latest Galileo Imaging Results

    NASA Technical Reports Server (NTRS)

    Williams, D. A.; Keszthelyi, L. P.; Davies, A. G.; Greeley, R.; Head, J. W., III

    2002-01-01

    This presentation will discuss analyses of the latest Galileo SSI (solid state imaging) high-resolution images of the Emakong lava channels and flow field on Jupiter's moon Io. Additional information is contained in the original extended abstract.

  1. High-Resolution Views of Io's Emakong Patera: Latest Galileo Imaging Results

    NASA Technical Reports Server (NTRS)

    Williams, D. A.; Keszthelyi, L. P.; Davies, A. G.; Greeley, R.; Head, J. W., III

    2002-01-01

    This presentation will discuss analyses of the latest Galileo SSI (solid state imaging) high-resolution images of the Emakong lava channels and flow field on Jupiter's moon Io. Additional information is contained in the original extended abstract.

  2. High resolution imaging of tunnels by magnetic resonance neurography

    PubMed Central

    Wang, Kenneth C.; Thawait, Shrey K.; Williams, Eric H.; Hashemi, Shahreyar Shar; Machado, Antonio J.; Carrino, John A.; Chhabra, Avneesh

    2011-01-01

    Peripheral nerves often traverse confined fibro-osseous and fibro-muscular tunnels in the extremities, where they are particularly vulnerable to entrapment and compressive neuropathy. This gives rise to various tunnel syndromes, characterized by distinct patterns of muscular weakness and sensory deficits. This article focuses on several upper and lower extremity tunnels, in which direct visualization of the normal and abnormal nerve in question is possible with high resolution 3T MR neurography (MRN). MRN can also serve as a useful adjunct to clinical and electrophysiologic exams by discriminating adhesive lesions (perineural scar) from compressive lesions (such as tumor, ganglion, hypertrophic callous, or anomalous muscles) responsible for symptoms, thereby guiding appropriate treatment. PMID:21479520

  3. High-Resolution Radio Imaging of the "Cosmic Hand"

    NASA Astrophysics Data System (ADS)

    Ng, Chi-Yung; Gaensler, Bryan; Slane, Patrick; Harvey-Smith, Lisa

    2012-10-01

    The 'Cosmic Hand' is an extremely complex pulsar wind nebula system powered by the energetic pulsar B1509-58 in supernova remnant G320.4-1.2 (MSH 15-52). Our recent ATCA observations revealed an intriguing jet-like linear feature of 1'-scale surrounding the pulsar. This could be the first known radio jet from a young pulsar, or a synchrotron wisp extending to high latitude. We propose here high-resolution observations to resolve its detailed morphology and to detect any time variability, with the aim to identify its physical nature. Confirming the jet nature could help reveal its launching mechanism and the particle acceleration process, while a wisp can indicate the flow structure beyond the equatorial plane. In either case, this will set an important example to refine our understanding of pulsar wind physics.

  4. Lensfree on-chip high-resolution imaging using two-way lighting, and its limitations

    NASA Astrophysics Data System (ADS)

    Adachi, Yasuhiko; Tamaki, Tokuhiko; Motomura, Hideto; Kato, Yoshihisa

    2016-03-01

    A high-magnification image of a biological sample can generally be obtained by an optical microscope with an objective lens, moving the image sensor with a sub-pixel shift and the subsequent image processing for super-resolution. However, to obtain a high-resolution image, a large number of images will be required for the super-resolution, and thus it is difficult to achieve real-time operation, and the field-of-view (FOV) is not sufficiently wide. The currently proposed digital holography technique places a sample on the image sensor and captures the interference fringe (hologram) to reconstruct a 3D high-resolution image in a computer. This technique ensures the features of a wide FOV, whereas the high resolution obtained by image processing cannot ensure real-time operation, because it requires recursive calculations of light propagation and adequate computer resources. To realize wide FOV and the real-time operation at the same time, we have developed a new technique: Lensfree on-chip high-resolution imaging using two-way lighting. High-resolution image is immediately obtained by image processing of the low-resolution images of the samples. This makes it possible to ensure a wide FOV, a deep depth of focus without the need for focus adjustment, and a continuously expanding operation. We also discuss the limitations of the high resolution.

  5. A new high-resolution electromagnetic method for subsurface imaging

    NASA Astrophysics Data System (ADS)

    Feng, Wanjie

    For most electromagnetic (EM) geophysical systems, the contamination of primary fields on secondary fields ultimately limits the capability of the controlled-source EM methods. Null coupling techniques were proposed to solve this problem. However, the small orientation errors in the null coupling systems greatly restrict the applications of these systems. Another problem encountered by most EM systems is the surface interference and geologic noise, which sometimes make the geophysical survey impossible to carry out. In order to solve these problems, the alternating target antenna coupling (ATAC) method was introduced, which greatly removed the influence of the primary field and reduced the surface interference. But this system has limitations on the maximum transmitter moment that can be used. The differential target antenna coupling (DTAC) method was proposed to allow much larger transmitter moments and at the same time maintain the advantages of the ATAC method. In this dissertation, first, the theoretical DTAC calculations were derived mathematically using Born and Wolf's complex magnetic vector. 1D layered and 2D blocked earth models were used to demonstrate that the DTAC method has no responses for 1D and 2D structures. Analytical studies of the plate model influenced by conductive and resistive backgrounds were presented to explain the physical phenomenology behind the DTAC method, which is the magnetic fields of the subsurface targets are required to be frequency dependent. Then, the advantages of the DTAC method, e.g., high-resolution, reducing the geologic noise and insensitive to surface interference, were analyzed using surface and subsurface numerical examples in the EMGIMA software. Next, the theoretical advantages, such as high resolution and insensitive to surface interference, were verified by designing and developing a low-power (moment of 50 Am 2) vertical-array DTAC system and testing it on controlled targets and scaled target coils. At last, a

  6. High Resolution Digital Radar Imaging of Rotating Objects

    DTIC Science & Technology

    1980-06-01

    1980 e ’ET Department of Electrical Engineering Image Processing Institute University of Southern California Los Angeles, California 90007 C tcSponsored...its disbibution i7 ~l;l,t• 3 IPI IMAGE PROCESSING INSTITUTE SRO 0i 009 64 USCIPIQ!? 970 p iGHkJESOLUTION.,,PGITAL jADAR -IMAGING OF ROTATING PBJECTS...by’ Yeh-Hua Peter/Chuan Department of Electrical Engineering Image Processing Institute University of Southern California Los Angeles, California

  7. High-resolution high-speed panoramic cardiac imaging system

    PubMed Central

    Evertson (In Memoriam), Dale W.; Holcomb, Mark R.; Eames, Matthew D.C.; Bray, Mark-Anthony P.; Sidorov, Veniamin Y.; Xu, Junkai; Wingard, Holley; Dobrovolny, Hana M.; Woods, Marcella C.; Gauthier, Daniel J.; Wikswo, John P.

    2008-01-01

    A panoramic cardiac imaging system consisting of three high-speed CCD cameras has been developed to image the surface electrophysiology of a rabbit heart via fluorescence imaging using a voltage-sensitive fluorescent dye. A robust, unique mechanical system was designed to accommodate the three cameras and to adapt to the requirements of future experiments. A unified computer interface was created for this application – a single workstation controls all three CCD cameras, illumination, and stimulation, and the stepping motor rotates the heart. The geometric reconstruction algorithms were adapted from a previous cardiac imaging system. We demonstrate the system by imaging a polymorphic cardiac tachycardia. PMID:18334422

  8. High Resolution Imaging of the Sun with CORONAS-1

    NASA Technical Reports Server (NTRS)

    Karovska, Margarita

    1998-01-01

    We applied several image restoration and enhancement techniques, to CORONAS-I images. We carried out the characterization of the Point Spread Function (PSF) using the unique capability of the Blind Iterative Deconvolution (BID) technique, which recovers the real PSF at a given location and time of observation, when limited a priori information is available on its characteristics. We also applied image enhancement technique to extract the small scale structure imbeded in bright large scale structures on the disk and on the limb. The results demonstrate the capability of the image post-processing to substantially increase the yield from the space observations by improving the resolution and reducing noise in the images.

  9. Towards Adaptive High-Resolution Images Retrieval Schemes

    NASA Astrophysics Data System (ADS)

    Kourgli, A.; Sebai, H.; Bouteldja, S.; Oukil, Y.

    2016-06-01

    Nowadays, content-based image-retrieval techniques constitute powerful tools for archiving and mining of large remote sensing image databases. High spatial resolution images are complex and differ widely in their content, even in the same category. All images are more or less textured and structured. During the last decade, different approaches for the retrieval of this type of images have been proposed. They differ mainly in the type of features extracted. As these features are supposed to efficiently represent the query image, they should be adapted to all kind of images contained in the database. However, if the image to recognize is somewhat or very structured, a shape feature will be somewhat or very effective. While if the image is composed of a single texture, a parameter reflecting the texture of the image will reveal more efficient. This yields to use adaptive schemes. For this purpose, we propose to investigate this idea to adapt the retrieval scheme to image nature. This is achieved by making some preliminary analysis so that indexing stage becomes supervised. First results obtained show that by this way, simple methods can give equal performances to those obtained using complex methods such as the ones based on the creation of bag of visual word using SIFT (Scale Invariant Feature Transform) descriptors and those based on multi scale features extraction using wavelets and steerable pyramids.

  10. Noninvasive mapping of subcutaneous vasculature with high resolution photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Lao, Yeqi; Xing, Da; Yang, Sihua

    2007-11-01

    As a novel hybrid imaging modality, photoacoustic (PA) imaging combines the merits of high optical contrast, good ultrasonic resolution and sufficient imaging depth, which may be of great benefit to noninvasively detect and monitor the pathological changes of subcutaneous vasculature, e.g., congenital vascular tumor and vascular malformation. In this paper, we apply a set of photoacoustic imaging system to image a sample of subcutaneous blood vessels, which is used to simulate the location of human's subcutaneous vasculature. Furthermore, an image of subcutaneous vasculature of the abdomen in a mouse is acquired in vivo. Laser pulses at a wavelength of 532 nm from a Q-switched Nd:YAG laser are employed as light source to generate PA signals in the experiments, because the optical absorption of whole blood is much stronger than that of other tissues at this wavelength. A needle polyvinylidene fluoride (PVDF) hydrophone with a diameter of 1mm is used to capture PA signals through a circular scan. The experimental results show that detailed structural information of subcutaneous vasculature, such as the shape and position of the blood vessels and the vessel branching, is clearly revealed by the PA imaging system. The spatial resolution of the PA imaging system reaches 80μm. Moreover, the reconstructed image of a mouse's abdomen in vivo demonstrates that this technique is suitable for noninvasive subcutaneous vasculature imaging. All of the results prove that the PA imaging can be used as a helpful tool for monitoring the pathological changes of subcutaneous vasculature.

  11. Towards Adaptive High-Resolution Images Retrieval Schemes

    NASA Astrophysics Data System (ADS)

    Kourgli, A.; Sebai, H.; Bouteldja, S.; Oukil, Y.

    2016-10-01

    Nowadays, content-based image-retrieval techniques constitute powerful tools for archiving and mining of large remote sensing image databases. High spatial resolution images are complex and differ widely in their content, even in the same category. All images are more or less textured and structured. During the last decade, different approaches for the retrieval of this type of images have been proposed. They differ mainly in the type of features extracted. As these features are supposed to efficiently represent the query image, they should be adapted to all kind of images contained in the database. However, if the image to recognize is somewhat or very structured, a shape feature will be somewhat or very effective. While if the image is composed of a single texture, a parameter reflecting the texture of the image will reveal more efficient. This yields to use adaptive schemes. For this purpose, we propose to investigate this idea to adapt the retrieval scheme to image nature. This is achieved by making some preliminary analysis so that indexing stage becomes supervised. First results obtained show that by this way, simple methods can give equal performances to those obtained using complex methods such as the ones based on the creation of bag of visual word using SIFT (Scale Invariant Feature Transform) descriptors and those based on multi scale features extraction using wavelets and steerable pyramids.

  12. High resolution PET breast imager with improved detection efficiency

    DOEpatents

    Majewski, Stanislaw

    2010-06-08

    A highly efficient PET breast imager for detecting lesions in the entire breast including those located close to the patient's chest wall. The breast imager includes a ring of imaging modules surrounding the imaged breast. Each imaging module includes a slant imaging light guide inserted between a gamma radiation sensor and a photodetector. The slant light guide permits the gamma radiation sensors to be placed in close proximity to the skin of the chest wall thereby extending the sensitive region of the imager to the base of the breast. Several types of photodetectors are proposed for use in the detector modules, with compact silicon photomultipliers as the preferred choice, due to its high compactness. The geometry of the detector heads and the arrangement of the detector ring significantly reduce dead regions thereby improving detection efficiency for lesions located close to the chest wall.

  13. Using Adobe Acrobat to create high-resolution line art images.

    PubMed

    Woo, Hyoun Sik; Lee, Jeong Min

    2009-08-01

    The purpose of this article is to introduce a method for using Adobe Acrobat to make high-resolution and high-quality line art images. High-resolution and high-quality line art images for radiology journal submission can be generated using Adobe Acrobat as a steppingstone, and the customized PDF conversion settings can be used for converting hybrid images, including both bitmap and vector components.

  14. Video Snapshots: Creating High-Quality Images from Video Clips.

    PubMed

    Sunkavalli, Kalyan; Joshi, Neel; Kang, Sing Bing; Cohen, Michael F; Pfister, Hanspeter

    2012-11-01

    We describe a unified framework for generating a single high-quality still image ("snapshot") from a short video clip. Our system allows the user to specify the desired operations for creating the output image, such as super resolution, noise and blur reduction, and selection of best focus. It also provides a visual summary of activity in the video by incorporating saliency-based objectives in the snapshot formation process. We show examples on a number of different video clips to illustrate the utility and flexibility of our system.

  15. Virtually distortion-free imaging system for large field, high resolution lithography

    DOEpatents

    Hawryluk, A.M.; Ceglio, N.M.

    1993-01-05

    Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position.

  16. Virtually distortion-free imaging system for large field, high resolution lithography

    DOEpatents

    Hawryluk, Andrew M.; Ceglio, Natale M.

    1993-01-01

    Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position.

  17. A high-resolution radio image of a young supernova

    NASA Technical Reports Server (NTRS)

    Bartel, N.; Rupen, M. P.; Shapiro, I. I.; Preston, R. A.; Rius, A.

    1991-01-01

    A VLBI radio images of the bright supernova 1986J, which occurred in the galaxy NGC891 at a distance of about 12 Mpc, is presented. No detailed image of any supernova or remnant has been obtained before so soon after the explosion. The image shows a shell of emission with jetlike protrusions. Analysis of the images should advance understanding of the dynamics of the expanding debris, the dissipation of energy into the surrounding circumstellar medium, and the evolution of the supernova into the remnant.

  18. High resolution image processing on low-cost microcomputers

    NASA Technical Reports Server (NTRS)

    Miller, R. L.

    1993-01-01

    Recent advances in microcomputer technology have resulted in systems that rival the speed, storage, and display capabilities of traditionally larger machines. Low-cost microcomputers can provide a powerful environment for image processing. A new software program which offers sophisticated image display and analysis on IBM-based systems is presented. Designed specifically for a microcomputer, this program provides a wide-range of functions normally found only on dedicated graphics systems, and therefore can provide most students, universities and research groups with an affordable computer platform for processing digital images. The processing of AVHRR images within this environment is presented as an example.

  19. High-Resolution and Animal Imaging Instrumentation and Techniques

    NASA Astrophysics Data System (ADS)

    Belcari, Nicola; Guerra, AlbertoDel

    During the last decade we have observed a growing interest in "in vivo" imaging techniques for small animals. This is due to the necessity of studying biochemical processes at a molecular level for pharmacology, genetic, and pathology investigations. This field of research is usually called "molecular imaging."Advances in biological understanding have been accompanied by technological advances in instrumentation and techniques and image-reconstruction software, resulting in improved image quality, visibility, and interpretation. The main technological challenge is then the design of systems with high spatial resolution and high sensitivity.

  20. High-Resolution Solar Imaging With Photon Sieves

    NASA Astrophysics Data System (ADS)

    Oktem, F. S.; Kamalabadi, F.; Davila, J. M.

    2014-12-01

    A photon sieve is a modification of a Fresnel zone plate in which open zones are replaced by a large number of circular holes. This lightweight optical device offers a superior image forming capability compared with the Fresnel zone plate, and is specially suited to observations at UV and x-ray wavelengths where refractive lenses are not available due to strong absorption of materials, and reflective mirrors are difficult to manufacture to achieve near diffraction-limited resolution. At these shorter wavelengths, photon sieves enable diffraction-limited imaging performance with relaxed manufacturing tolerances, and simple and low-cost fabrication. In this work, we present a new photon sieve imaging modality that, unlike previous designs, takes advantage of chromatic aberration. The fact that different wavelengths are focused at different distances from photon sieve is exploited to develop a novel multi-spectral imaging technique. The idea is to use a photon sieve imaging system with a moving detector which records images at different planes. Each measurement consists of superimposed images of different wavelengths, with each individual image being either in focus or out of focus. For spatially incoherent illumination, we study the problem of recovering the individual images from these superimposed measurements. We first formulate the discrete forward problem using the closed-form Fresnel imaging formulas. The inverse problem is then a multi-frame deconvolution problem involving multiple objects, and is formulated as a maximum posterior estimation problem. The resulting nonlinear optimization problem is solved using a fixed-point iterative algorithm. In contrast to traditional spectral imagers employing a series of wavelength filters, the proposed technique relies on a simple optical system, but incorporates powerful image processing methods to form spectral images computationally. In addition to diffraction-limited high spatial resolution enabled by photon sieves

  1. A High Resolution Imaging Survey of A Stars with AEOS

    NASA Astrophysics Data System (ADS)

    Patience, J.; Macintosh, B. A.; Max, C. E.

    2001-12-01

    We are conducting a companion search to field and cluster A stars using the U. S. Air Force Advanced Electro-Optical System (AEOS) which includes a 941 actuator adaptive optics system on a 3.7m telescope on Haleakala. Operating at I-band, the diffraction limit of the system is 0".05. This program is designed to address questions in binary star formation and stellar X-ray activity. The first goal of our project is to obtain high resolution adaptive optics observations of a large sample of early-type stars in order to extend the mass range covered by binary star searches and to test binary formation theories. In addition to providing insight into the star formation process, studies of companion stars may also explain the unexpected detection of X-rays from A stars. Since A stars lack both the strong winds of the earlier spectral types and the dynamos of the later spectral types, they are not expected to produce X-rays, however, some A stars are detected as X-ray sources. Typical ROSAT error boxes can include a companion star and the second goal of our program is to investigate the possibility that companions are the true source of X-ray emission from A stars. A stars in the young open clusters Coma Berenices and the Pleiades have been targeted as well as field A stars. Our initial results show a binary fraction for X-ray detected A stars that is twice as high as that of non-detected A stars. We gratefully acknowledge support from the Air Force Office of Scientific Research through grant AFOSR-ISSA-01-NM-016. This work was performed under the auspices of the US Department of Energy by the University of California Lawrence Livermore National Laboratory under contract W-7405-ENG-48.

  2. High-resolution light field reconstruction using a hybrid imaging system.

    PubMed

    Wang, Xiang; Li, Lin; Hou, GuangQi

    2016-04-01

    Recently, light field cameras have drawn much attraction for their innovative performance in photographic and scientific applications. However, narrow baselines and constrained spatial resolution of current light field cameras impose restrictions on their usability. Therefore, we design a hybrid imaging system containing a light field camera and a high-resolution digital single lens reflex camera, and these two kinds of cameras share the same optical path with a beam splitter so as to achieve the reconstruction of high-resolution light fields. The high-resolution 4D light fields are reconstructed with a phase-based perspective variation strategy. First, we apply complex steerable pyramid decomposition on the high-resolution image from the digital single lens reflex camera. Then, we perform phase-based perspective-shift processing with the disparity value, which is extracted from the upsampled light field depth map, to create high-resolution synthetic light field images. High-resolution digital refocused images and high-resolution depth maps can be generated in this way. Furthermore, controlling the magnitude of the perspective shift enables us to change the depth of field rendering in the digital refocused images. We show several experimental results to demonstrate the effectiveness of our approach.

  3. High-resolution adaptive imaging of a single atom

    NASA Astrophysics Data System (ADS)

    Wong-Campos, J. D.; Johnson, K. G.; Neyenhuis, B.; Mizrahi, J.; Monroe, C.

    2016-09-01

    Optical imaging systems are used extensively in the life and physical sciences because of their ability to non-invasively capture details on the microscopic and nanoscopic scales. Such systems are often limited by source or detector noise, image distortions and human operator misjudgement. Here, we report a general, quantitative method to analyse and correct these errors. We use this method to identify and correct optical aberrations in an imaging system for single atoms and realize an atomic position sensitivity of ˜0.5 nm Hz-1/2 with a minimum uncertainty of 1.7 nm, allowing the direct imaging of atomic motion. This is the highest position sensitivity ever measured for an isolated atom and opens up the possibility of performing out-of-focus three-dimensional particle tracking, imaging of atoms in three-dimensional optical lattices or sensing forces at the yoctonewton (10-24 N) scale.

  4. Maximum bandwidth snapshot channeled imaging polarimeter with polarization gratings

    NASA Astrophysics Data System (ADS)

    LaCasse, Charles F.; Redman, Brian J.; Kudenov, Michael W.; Craven, Julia M.

    2016-05-01

    Compact snapshot imaging polarimeters have been demonstrated in literature to provide Stokes parameter estimations for spatially varying scenes using polarization gratings. However, the demonstrated system does not employ aggressive modulation frequencies to take full advantage of the bandwidth available to the focal plane array. A snapshot imaging Stokes polarimeter is described and demonstrated through results. The simulation studies the challenges of using a maximum bandwidth configuration for a snapshot polarization grating based polarimeter, such as the fringe contrast attenuation that results from higher modulation frequencies. Similar simulation results are generated and compared for a microgrid polarimeter. Microgrid polarimeters are instruments where pixelated polarizers are superimposed onto a focal plan array, and this is another type of spatially modulated polarimeter, and the most common design uses a 2x2 super pixel of polarizers which maximally uses the available bandwidth of the focal plane array.

  5. Study of fish response using particle image velocimetry and high-speed, high-resolution imaging

    SciTech Connect

    Deng, Z.; Richmond, M. C.; Mueller, R. P.; Gruensch, G. R.

    2004-10-01

    Fish swimming has fascinated both engineers and fish biologists for decades. Digital particle image velocimetry (DPIV) and high-speed, high-resolution digital imaging are recently developed analysis tools that can help engineers and biologists better understand how fish respond to turbulent environments. This report details studies to evaluate DPIV. The studies included a review of existing literature on DPIV, preliminary studies to test the feasibility of using DPIV conducted at our Flow Biology Laboratory in Richland, Washington September through December 2003, and applications of high-speed, high-resolution digital imaging with advanced motion analysis to investigations of fish injury mechanisms in turbulent shear flows and bead trajectories in laboratory physical models. Several conclusions were drawn based on these studies, which are summarized as recommendations for proposed research at the end of this report.

  6. Dedicated mobile high resolution prostate PET imager with an insertable transrectal probe

    DOEpatents

    Majewski, Stanislaw; Proffitt, James

    2010-12-28

    A dedicated mobile PET imaging system to image the prostate and surrounding organs. The imaging system includes an outside high resolution PET imager placed close to the patient's torso and an insertable and compact transrectal probe that is placed in close proximity to the prostate and operates in conjunction with the outside imager. The two detector systems are spatially co-registered to each other. The outside imager is mounted on an open rotating gantry to provide torso-wide 3D images of the prostate and surrounding tissue and organs. The insertable probe provides closer imaging, high sensitivity, and very high resolution predominately 2D view of the prostate and immediate surroundings. The probe is operated in conjunction with the outside imager and a fast data acquisition system to provide very high resolution reconstruction of the prostate and surrounding tissue and organs.

  7. Development toward high-resolution X-ray phase imaging.

    PubMed

    Momose, Atsushi

    2017-06-01

    Since the 1990s, the use of X-ray phase contrast has been extensively studied for imaging weakly absorbing objects consisting of low-Z elements such as biological soft tissues and polymers. The development of X-ray microscopy was also progressing during this time, although absorption contrast was only available. It was straightforward and important to develop phase-contrast X-ray microscopy. One characteristic in the development is that quantitative phase measurement is possible through the acquisition of phase-contrast images under a specific procedure, thanks to digital X-ray image detectors. Therefore, such a technique is called 'phase imaging' rather than phase-contrast imaging in this review. Highly sensitive three-dimensional phase imaging is feasible in combination with tomography. This article reviews the progress in X-ray phase imaging, especially with regards to X-ray microscopy. © The Author 2017. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. High-Resolution Image of Europa's Ridged Plains

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This spectacular image taken by NASA's Galileo spacecraft camera shows a region of ridged plains on Jupiter's moon Europa. The plains are comprised of many parallel and cross-cutting ridges, commonly in pairs. The majority of the region is of very bright, but darker material is seen primarily in valleys between ridges. Some of the most prominent ridges have dark deposits along their margins and in their central valleys. Some of this dark material probably moved down the flanks of the ridges and has piled up along their bases. The most prominent ridges are about a kilometer in width (less than a mile). In the top right hand corner of the image the end of a dark wide ridge (about 2 kilometers or 1.2 miles across) is visible. Several deep fractures cut through this ridge and continue into the plains. The brightness of the region suggests that frost covers much of Europa's surface. This image looks different from those obtained earlier in Galileo's mission, because this image was taken with the Sun higher in Europa's sky.

    This image was taken on December 16, 1997 at a range of 1,300 kilometers (800 miles) by Galileo's solid state imaging system. North is to the top of the picture, and the Sun illuminates the surface from the upper left. This image, centered at approximately 14 degrees south latitude and 194 degrees west longitude, covers an area approximately 20 kilometers (12 miles) on each side. The resolution is 26 meters (85 feet) per picture element.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/ galileo.

  9. High-Resolution Image of Europa's Ridged Plains

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This spectacular image taken by NASA's Galileo spacecraft camera shows a region of ridged plains on Jupiter's moon Europa. The plains are comprised of many parallel and cross-cutting ridges, commonly in pairs. The majority of the region is of very bright, but darker material is seen primarily in valleys between ridges. Some of the most prominent ridges have dark deposits along their margins and in their central valleys. Some of this dark material probably moved down the flanks of the ridges and has piled up along their bases. The most prominent ridges are about a kilometer in width (less than a mile). In the top right hand corner of the image the end of a dark wide ridge (about 2 kilometers or 1.2 miles across) is visible. Several deep fractures cut through this ridge and continue into the plains. The brightness of the region suggests that frost covers much of Europa's surface. This image looks different from those obtained earlier in Galileo's mission, because this image was taken with the Sun higher in Europa's sky.

    This image was taken on December 16, 1997 at a range of 1,300 kilometers (800 miles) by Galileo's solid state imaging system. North is to the top of the picture, and the Sun illuminates the surface from the upper left. This image, centered at approximately 14 degrees south latitude and 194 degrees west longitude, covers an area approximately 20 kilometers (12 miles) on each side. The resolution is 26 meters (85 feet) per picture element.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/ galileo.

  10. Adaptive Optics Technology for High-Resolution Retinal Imaging

    PubMed Central

    Lombardo, Marco; Serrao, Sebastiano; Devaney, Nicholas; Parravano, Mariacristina; Lombardo, Giuseppe

    2013-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging. PMID:23271600

  11. Adaptive optics technology for high-resolution retinal imaging.

    PubMed

    Lombardo, Marco; Serrao, Sebastiano; Devaney, Nicholas; Parravano, Mariacristina; Lombardo, Giuseppe

    2012-12-27

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging.

  12. High Resolution Imaging of Circumstellar Disks at Millimeter Wavelengths

    NASA Technical Reports Server (NTRS)

    Wilner, David J.

    2004-01-01

    We summarize progress on our program to use high angular resolution imaging of thermal dust continuum emission at millimeter and submillimeter wavelengths to probe the structure of protoplanetary disks and debris disks around nearby stars.

  13. Hypertelescopes: The Challenge of Direct Imaging at High Resolution

    NASA Astrophysics Data System (ADS)

    Labeyrie, A.

    2013-03-01

    Sparse optical interferometric arrays of many apertures can produce direct images in the densified-pupil mode, also called "hypertelescope" mode. Pending the introduction of adaptive optics for cophasing, indirect images can also be reconstructed with speckle imaging techniques. But adaptive phasing is preferable, when a sufficiently bright guide star is available. Several wave sensing techniques, by-products of those used on monolithic telescopes for some of them, are potentially usable. For cophased direct images of very faint sources in the absence of a natural guide star, a modified form of the Laser Guide Star techniques demonstrated on conventional and segmented telescopes is described. Preliminary testing in laboratory suggests further investigation. Recorded images, assumed co-phased, are also improvable post-detection with optical aperture-synthesis techniques such as Earth rotation synthesis, where data from successive exposures are combined incoherently. Nevertheless, the gain becomes modest if hundreds of sub-apertures are used. Image deconvolution techniques are also applicable, if suitably modified as demonstrated by Aime et al. (2012), and Mary (2012). Their modified deconvolution algorithms can extend the Direct Imaging Field (also called Clean Field) of hypertelescopes. More sub-apertures at given collecting area, implying that their size is reduced, improve the direct-imaging performance. The predictable trend thus favors systems combining hundreds of sub-apertures of modest size, if workable designs can be evolved. One such design, the "Ubaye Hypertelescope" entering the initial testing phase in the southern Alps, has a fixed spherical meta-mirror with a 57 m effective aperture, expandable to 200 m. Preliminary results suggest that larger versions, whether spherical or active paraboloidal, can reach a kilometric aperture size at terrestrial sites having a suitable concave topography. In space, hypertelescope meta-apertures spanning up to 100 000

  14. Innovative Techniques for High-Resolution Imaging and Precision Tracking

    DTIC Science & Technology

    1990-04-20

    Gorlin , and M. Elbaum, "Imaging Corrrelography", preprint, 1987 8. M. Elbaum, D. Brenner, B. Kingsbury, J. Nowakowski, "Autodyning Tracking of Moving...10. M. Elbaum, J. Nowakowski, D. Gutkowicz-Krusin, M. Wlodawski, and Y. Gorlin , Opt. Len. 13, 81 (1988) C49-701 -7. RIVERSIDE RESEARCH INSTITUTE 2... Gorlin , and M. Elbaum, "Imaging Correlography", RRI preprint, (1987). 5. J. Nowakowski. "Analysis of Autodyne Detection", RRI preprint (1987). 6. P

  15. High Resolution Global Topography of Eros from NEAR Imaging and LIDAR Data

    NASA Technical Reports Server (NTRS)

    Gaskell, Robert W.; Konopliv, A.; Barnouin-Jha, O.; Scheeres, D.

    2006-01-01

    Principal Data Products: Ensemble of L-maps from SPC, Spacecraft state, Asteroid pole and rotation. Secondary Products: Global topography model, inertia tensor, gravity. Composite high resolution topography. Three dimensional image maps.

  16. Evaluation of image quality characteristics of reduction image in high resolution liquid crystal display

    NASA Astrophysics Data System (ADS)

    Kimura, Yukiyoshi; Yokoyama, Daigo; Fujita, Naotoshi; Kodera, Yoshie

    2011-03-01

    With recent developments, digital mammograms can be obtained with a small pixel size, i.e., high resolution; however, the matrix size increases. Therefore, when the image is thinned out, image information is lost when the image is displayed on a liquid crystal display (LCD). To resolve this issue, we have developed a super high resolution liquid crystal display (SHR-LCD) by using a novel resolution enhancement technology for independent subpixel driving (ISD) with three subpixels in each pixel element. However, the lack of image information caused by thinning of the image cannot be ignored because the matrix size of a phase contrast mammogram (PCM) is very large as compared to that of a conventional mammogram. We obtained noise and edge images by using the geometrical layouts of the PCM (7080 x 9480). We measured the Wiener spectrum (WS), modulation transfer function (MTF), and noise-equivalent number of quanta (NEQ) of the images reduced by the nearest-neighbor, bilinear, and bicubic (sharpness and smooth) interpolations. The reduction rate was approximately 0.14. We measured the WS and MTF when the PCM image was displayed on a 5-megapixel (MP) and 15-MP LCD. The bilinear interpolation technique gave the best image quality. The image quality was further improved by using a 15-MP SHR-LCD.

  17. High-resolution photoacoustic imaging of ocular tissues.

    PubMed

    Silverman, Ronald H; Kong, Fanting; Chen, Y C; Lloyd, Harriet O; Kim, Hyung Ham; Cannata, Jonathan M; Shung, K Kirk; Coleman, D Jackson

    2010-05-01

    Optical coherence tomography (OCT) and ultrasound (US) are methods widely used for diagnostic imaging of the eye. These techniques detect discontinuities in optical refractive index and acoustic impedance, respectively. Because these both relate to variations in tissue density or composition, OCT and US images share a qualitatively similar appearance. In photoacoustic imaging (PAI), short light pulses are directed at tissues, pressure is generated due to a rapid energy deposition in the tissue volume and thermoelastic expansion results in generation of broadband US. PAI thus depicts optical absorption, which is independent of the tissue characteristics imaged by OCT or US. Our aim was to demonstrate the application of PAI in ocular tissues and to do so with lateral resolution comparable to OCT. We developed two PAI assemblies, both of which used single-element US transducers and lasers sharing a common focus. The first assembly had optical and 35-MHz US axes offset by a 30 degrees angle. The second assembly consisted of a 20-MHz ring transducer with a coaxial optics. The laser emitted 5-ns pulses at either 532 nm or 1064 nm, with spot sizes at the focus of 35 microm for the angled probe and 20 microm for the coaxial probe. We compared lateral resolution by scanning 12.5 microm diameter wire targets with pulse/echo US and PAI at each wavelength. We then imaged the anterior segment in whole ex vivo pig eyes and the choroid and ciliary body region in sectioned eyes. PAI data obtained at 1064 nm in the near infrared had higher penetration but reduced signal amplitude compared to that obtained using the 532 nm green wavelength. Images were obtained of the iris, choroid and ciliary processes. The zonules and anterior cornea and lens surfaces were seen at 532 nm. Because the laser spot size was significantly smaller than the US beamwidth at the focus, PAI images had superior resolution than those obtained using conventional US.

  18. High-resolution passive microwave imaging of the surface of the Earth

    NASA Technical Reports Server (NTRS)

    Swift, C. T.

    1981-01-01

    The physics of passive microwave observations of the Earth and the system requirements for high-resolution imaging within this spectral band are summarized. High resolution is achieved in a straightforward manner by increasing the size of the primary antenna. However, with a single receiver, it is shown that the combination of high resolution and crosstrack scanning cannot produce images which have valuable geophysical content. The concept of a multiple receiver array located in the focal plane is presented as the only practical solution to the dilemma. Exploring this concept, system requirements are generated which, for the first order, appear to offer solutions to the problem.

  19. High resolution resonance ionization imaging detector and method

    DOEpatents

    Winefordner, James D.; Matveev, Oleg I.; Smith, Benjamin W.

    1999-01-01

    A resonance ionization imaging device (RIID) and method for imaging objects using the RIID are provided, the RIID system including a RIID cell containing an ionizable vapor including monoisotopic atoms or molecules, the cell being positioned to intercept scattered radiation of a resonance wavelength .lambda..sub.1 from the object which is to be detected or imaged, a laser source disposed to illuminate the RIID cell with laser radiation having a wavelength .lambda..sub.2 or wavelengths .lambda..sub.2, .lambda..sub.3 selected to ionize atoms in the cell that are in an excited state by virtue of having absorbed the scattered resonance laser radiation, and a luminescent screen at the back surface of the RIID cell which presents an image of the number and position of charged particles present in the RIID cell as a result of the ionization of the excited state atoms. The method of the invention further includes the step of initially illuminating the object to be detected or imaged with a laser having a wavelength selected such that the object will scatter laser radiation having the resonance wavelength .lambda..sub.1.

  20. High resolution spatial map imaging of a gaseous target

    NASA Astrophysics Data System (ADS)

    Stei, Martin; von Vangerow, Johannes; Otto, Rico; Kelkar, Aditya H.; Carrascosa, Eduardo; Best, Thorsten; Wester, Roland

    2013-06-01

    Electrostatic ion imaging with the velocity map imaging mode is a widely used method in atomic and molecular physics and physical chemistry. In contrast, the spatial map imaging (SMI) mode has received very little attention, despite the fact that it has been proposed earlier [A. T. J. B. Eppink and D. H. Parker, Rev. Sci. Instrum. 68, 3477 (1997)], 10.1063/1.1148310. Here, we present a detailed parametric characterization of SMI both by simulation and experiment. One-, two- and three-dimensional imaging modes are described. The influence of different parameters on the imaging process is described by means of a Taylor expansion. To experimentally quantify elements of the Taylor expansion and to infer the spatial resolution of our spectrometer, photoionization of toluene with a focused laser beam has been carried out. A spatial resolution of better than 4 μm out of a focal volume of several mm in diameter has been achieved. Our results will be useful for applications of SMI to the characterization of laser beams, the overlap control of multiple particle or light beams, and the determination of absolute collision cross sections.

  1. Black phosphorus photodetector for multispectral, high-resolution imaging.

    PubMed

    Engel, Michael; Steiner, Mathias; Avouris, Phaedon

    2014-11-12

    Black phosphorus is a layered semiconductor that is intensely researched in view of applications in optoelectronics. In this letter, we investigate a multilayer black phosphorus photodetector that is capable of acquiring high-contrast (V > 0.9) images both in the visible (λVIS = 532 nm) as well as in the infrared (λIR = 1550 nm) spectral regime. In a first step, by using photocurrent microscopy, we map the active area of the device and we characterize responsivity and gain. In a second step, by deploying the black phosphorus device as a point-like detector in a confocal microsope setup, we acquire diffraction-limited optical images with submicron resolution. The results demonstrate the usefulness of black phosphorus as an optoelectronic material for hyperspectral imaging applications.

  2. High Resolution SZE Imaging of Galaxy Clusters with MUSTANG-2

    NASA Astrophysics Data System (ADS)

    Mason, Brian S.; Romero, Charles; Dicker, Simon; Mroczkowski, Tony; Stanchfield, Sara; Sayers, Jack; Czakon, Nicole G.; Sarazin, Craig L.; Golwala, Sunil R.; Devlin, Mark J.

    2016-01-01

    Over the past several years the 3.3mm MUSTANG bolometer camera on the GBT has been making pioneering, 10" resolution images of the Sunyaev-Zel'dovich Effect (SZE) in galaxy clusters. These measurements, focusing mainly on the CLASH sample, provide a view of the ICM state and dynamics which complements that provided by other common probes (x-ray imaging and spectroscopy and lower resolution SZE imaging). We present results from this survey, including ICM pressure profile measurements obtained by combining MUSTANG and BOLOCAM data, and discuss work that is underway. In early 2015, MUSTANG's next-generation successor (MUSTANG-2) achieved first light in an engineering run on the GBT. In early 2016 the fully populated 215-feedhorn MUSTANG-2 camera will be installed for an early science run. We present an overview of key SZ science that this instrument aims to address.

  3. Development of high resolution imaging detectors for x ray astronomy

    NASA Technical Reports Server (NTRS)

    Murray, S. S.; Schwartz, D. A.

    1992-01-01

    This final report summarizes our past activities and discusses the work performed over the period of 1 April 1990 through 1 April 1991 on x-ray optics, soft x-ray (0.1 - 10 KeV) imaging detectors, and hard x-ray (10 - 300 KeV) imaging detectors. If microchannel plates (MCPs) can be used to focus x-rays with a high efficiency and good angular resolution, they will revolutionize the field of x-ray optics. An x-ray image of a point source through an array of square MCP pores compared favorably with our ray tracing model for the MCP. Initial analysis of this image demonstrates the feasibility of MCPs for soft x-rays. Our work continues with optimizing the performance of our soft x-ray MCP imaging detectors. This work involves readout technology that should provide improved MCP readout devices (thin film crossed grid, curved, and resistive sheets), defect removal in MCPs, and photocathode optimization. In the area of hard x-ray detector development we have developed two different techniques for producing a CsI photocathode thickness of 10 to 100 microns, such that it is thick enough to absorb the high energy x-rays and still allow the photoelectrons to escape to the top MCP of a modified soft x-ray imaging detector. The methods involve vacuum depositing a thick film of CsI on a strong back, and producing a converter device that takes the place of the photocathode.

  4. High Resolution Emission and Transmission Imaging Using the Same Detector.

    PubMed

    Panse, Ashish S; Jain, A; Wang, W; Yao, R; Bednarek, D R; Rudin, S

    2010-10-30

    We demonstrate the capability of one detector, the Micro-Angiographic Fluoroscope (MAF) detector, to image for two types of applications: nuclear medicine imaging and radiography. The MAF has 1024 × 1024 pixels with an effective pixel size of 35 microns and is capable of real-time imaging at 30 fps. It has a CCD camera coupled by a fiber-optic taper to a light image intensifier (LII) viewing a 300-micron thick CsI phosphor. The large variable gain of the LII provides quantum-limited operation with little additive instrumentation noise and enables operation in both energy-integrating (EI) and sensitive low-exposure single photon counting (SPC) modes. We used the EI mode to take a radiograph, and the SPC mode to image a custom phantom filled with 1 mCi of I-125. The phantom is made of hot rods with diameters ranging from 0.9 mm to 2.3 mm. A 1 mm diameter parallel hole, medium energy gamma camera collimator was placed between the phantom and the MAF and was moved multiple times at equal intervals in random directions to eliminate the grid pattern corresponding to the collimator septa. Data was acquired at 20 fps. Two algorithms to localize the events were used: 1) simple threshold and 2) a weighted centroid method. Although all the hot rods could be clearly identified, the image generated with the simple threshold method shows more blurring than that with the weighted centroid method. With the diffuse cluster of pixels from each single detection event localized to a single pixel, the weighted centroid method shows improved spatial resolution. A radiograph of the phantom was taken with the same MAF in EI mode without the collimator. It shows clear structural details of the rods. Compared to the radiograph, the sharpness of the emission image is limited by the collimator resolution and could be improved by optimized collimator design. This study demonstrated that the same MAF detector can be used in both radioisotope and x-ray imaging, combining the benefits of each.

  5. Low power, high resolution MAPS for particle tracking and imaging

    NASA Astrophysics Data System (ADS)

    Giubilato, P.; Cavicchioli, C.; Chalmet, P.; Kugathasan, T.; Marin Tobon, C.; Mattiazzo, S.; Mugnier, H.; Pantano, D.; Pozzobon, N.; Rousset, J.; Snoeys, W.; Yang, P.

    2015-05-01

    We describe here the first monolithic pixel detector prototype embedding the OrthoPix architecture, specifically designed to deal with imaging applications where the relevant number of pixel hit per frame (occupancy) is small (on the order or less than 1%), like in High Energy Physics, Medical Imaging and other applications. Current state of the art employs complex circuitry into the pixel cell to discriminate relevant signals, leading to an extremely effective, non-destructive compression at the price of large power consumption and pixel area limitations. The OrthoPix architecture instead implements a passive projective compression scheme, leading to low power, small pixel cell and large area devices.

  6. Fast, High-Resolution Terahertz Radar Imaging at 25 Meters

    NASA Technical Reports Server (NTRS)

    Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria; Talukder, Ashit; Panangadan, Anand V.; Peay, Chris S.; Siegel, Peter H.

    2010-01-01

    We report improvements in the scanning speed and standoff range of an ultra-wide bandwidth terahertz (THz) imaging radar for person-borne concealed object detection. Fast beam scanning of the single-transceiver radar is accomplished by rapidly deflecting a flat, light-weight subreflector in a confocal Gregorian optical geometry. With RF back-end improvements also implemented, the radar imaging rate has increased by a factor of about 30 compared to that achieved previously in a 4 m standoff prototype instrument. In addition, a new 100 cm diameter ellipsoidal aluminum reflector yields beam spot diameters of approximately 1 cm over a 50x50 cm field of view at a range of 25 m, although some aberrations are observed that probably arise from misaligned optics. Through-clothes images of a concealed threat at 25 m range, acquired in 5 seconds, are presented, and the impact of reduced signal-to-noise from an even faster frame rate is analyzed. These results inform the system requirements for eventually achieving sub-second or video-rate THz radar imaging.

  7. A high-resolution unconventional imager for missile defense applications

    NASA Astrophysics Data System (ADS)

    1995-05-01

    During this reporting period a detailed MathCAD (trademark) - based ASI signal performance model was completed and checked. Also, the laser energy requirements were estimated for the three potential ASI military applications reported last period. The results were discouragingly high, ranging from 35 Joules to 135 Joules per pulse (The laser pulses N times to collect an N x N pixel image). This led to a careful analysis of tradeoffs affecting transmit energy requirements. A significant understanding resulted: the ASI imager works extremely well (from a laser energy point of view) when very small objects like missiles or space debris are imaged over large distances. Also, laser energy requirements decrease when the transmitter wavelength is increased. In each case the smallest speckle lobe increases in size and more photons are collected as the subaperture size is scaled accordingly. Interestingly, this suggests that ASI can fill a very unique niche where radar cannot supply the spatial resolution and conventional optics are too bulky and expensive to perform long-range non-cooperative target identification of small targets. Hence ASI may be 'the only game in town' as an adjunct sensor for Patriot missile batteries, as a non-cooperative target I.D. sensor on fighter aircraft protecting a Navy carrier group or as a space debris imager protecting the space shuttle or space station.

  8. High-resolution imaging using a translating coded aperture

    NASA Astrophysics Data System (ADS)

    Mahalanobis, Abhijit; Shilling, Richard; Muise, Robert; Neifeld, Mark

    2017-08-01

    It is well known that a translating mask can optically encode low-resolution measurements from which higher resolution images can be computationally reconstructed. We experimentally demonstrate that this principle can be used to achieve substantial increase in image resolution compared to the size of the focal plane array (FPA). Specifically, we describe a scalable architecture with a translating mask (also referred to as a coded aperture) that achieves eightfold resolution improvement (or 64∶1 increase in the number of pixels compared to the number of focal plane detector elements). The imaging architecture is described in terms of general design parameters (such as field of view and angular resolution, dimensions of the mask, and the detector and FPA sizes), and some of the underlying design trades are discussed. Experiments conducted with different mask patterns and reconstruction algorithms illustrate how these parameters affect the resolution of the reconstructed image. Initial experimental results also demonstrate that the architecture can directly support task-specific information sensing for detection and tracking, and that moving objects can be reconstructed separately from the stationary background using motion priors.

  9. Fast high-resolution terahertz radar imaging at 25 meters

    NASA Astrophysics Data System (ADS)

    Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria; Talukder, Ashit; Panangadan, Anand V.; Peay, Chris S.; Mehdi, Imran; Siegel, Peter H.

    2010-04-01

    We report improvements in the scanning speed and standoff range of an ultra-wide bandwidth terahertz (THz) imaging radar for person-borne concealed object detection. Fast beam scanning of the single-transceiver radar is accomplished by rapidly deflecting a flat, light-weight subreflector in a confocal Gregorian optical geometry. With RF back-end improvements also implemented, the radar imaging rate has increased by a factor of about 30 compared to that achieved previously in a 4 m standoff prototype instrument. In addition, a new 100 cm diameter ellipsoidal aluminum reflector yields beam spot diameters of approximately 1 cm over a 50×50 cm field of view at a range of 25 m, although some aberrations are observed that probably arise from misaligned optics. Through-clothes images of concealed pipes at 25 m range, acquired in 5 seconds, are presented, and the impact of reduced signal-to-noise from an even faster frame rate is analyzed. These results inform the requirements for eventually achieving sub-second or video-rate THz radar imaging.

  10. Fast, High-Resolution Terahertz Radar Imaging at 25 Meters

    NASA Technical Reports Server (NTRS)

    Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria; Talukder, Ashit; Panangadan, Anand V.; Peay, Chris S.; Siegel, Peter H.

    2010-01-01

    We report improvements in the scanning speed and standoff range of an ultra-wide bandwidth terahertz (THz) imaging radar for person-borne concealed object detection. Fast beam scanning of the single-transceiver radar is accomplished by rapidly deflecting a flat, light-weight subreflector in a confocal Gregorian optical geometry. With RF back-end improvements also implemented, the radar imaging rate has increased by a factor of about 30 compared to that achieved previously in a 4 m standoff prototype instrument. In addition, a new 100 cm diameter ellipsoidal aluminum reflector yields beam spot diameters of approximately 1 cm over a 50x50 cm field of view at a range of 25 m, although some aberrations are observed that probably arise from misaligned optics. Through-clothes images of a concealed threat at 25 m range, acquired in 5 seconds, are presented, and the impact of reduced signal-to-noise from an even faster frame rate is analyzed. These results inform the system requirements for eventually achieving sub-second or video-rate THz radar imaging.

  11. High-Resolution MOC Image of Phobos with Graphics Overlay

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. The white boxes indicate the location of the subframes or close-ups: that on the left is C and that on the right is D. Each box is 1.92 kilometers (1.19 miles) square. The image shows several new features of this lumpy moon -- features that are associated with the prominent crater seen in the upper left quarter of the image. This is the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater (D), and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. The far wall of the crater shows lighter and darker streaks going down the slopes (C). Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Thermal Emission Spectrometer is operated by Arizona State University and was built by Raytheon Santa Barbara Remote Sensing. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  12. High-Resolution MOC Image of Phobos with Graphics Overlay

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. The white boxes indicate the location of the subframes or close-ups: that on the left is C and that on the right is D. Each box is 1.92 kilometers (1.19 miles) square. The image shows several new features of this lumpy moon -- features that are associated with the prominent crater seen in the upper left quarter of the image. This is the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater (D), and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. The far wall of the crater shows lighter and darker streaks going down the slopes (C). Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Thermal Emission Spectrometer is operated by Arizona State University and was built by Raytheon Santa Barbara Remote Sensing. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  13. High-Resolution MOC Image of Phobos' Face

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. The minimum distance between the spacecraft and Phobos was 1,080 kilometers (671 miles). Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite. The image shows several new features of this lumpy moon -- features that are associated with the prominent crater seen in the upper left quarter of the image. This is the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater (D), and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. The far wall of the crater shows lighter and darker streaks going down the slopes (C). The presence of material of different brightness on the far crater slopes and in some of the grooves shows that the satellite is heterogeneous (that is, it is made of a mixture of different types of materials). The motion of debris down slopes is guided by gravity, which is only about 1/1000th that of the Earth -- e.g., a 68-kilogram (150- pound) person would weigh only about 57 grams (2 ounces) on Phobos. Previous images from the Viking spacecraft in the 1970's were not of sufficient resolution to show the effectiveness of gravity on Phobos in moving material down slopes.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA

  14. High-Resolution MOC Image of Phobos' Face

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. The minimum distance between the spacecraft and Phobos was 1,080 kilometers (671 miles). Phobos was observed by both the Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES). This image is one of the highest resolution images (4 meters or 13 feet per picture element or pixel) ever obtained of the Martian satellite. The image shows several new features of this lumpy moon -- features that are associated with the prominent crater seen in the upper left quarter of the image. This is the largest crater on Phobos, Stickney, 10 kilometers (6 miles) in diameter. Individual boulders are visible on the near rim of the crater (D), and are presumed to be ejecta blocks from the impact that formed Stickney. Some of these boulders are enormous - more than 50 meters (160 feet) across. Also crossing at and near the rim of Stickney are shallow, elongated depressions called grooves. This crater is nearly half the size of Phobos and these grooves may be fractures caused by its formation. The far wall of the crater shows lighter and darker streaks going down the slopes (C). The presence of material of different brightness on the far crater slopes and in some of the grooves shows that the satellite is heterogeneous (that is, it is made of a mixture of different types of materials). The motion of debris down slopes is guided by gravity, which is only about 1/1000th that of the Earth -- e.g., a 68-kilogram (150- pound) person would weigh only about 57 grams (2 ounces) on Phobos. Previous images from the Viking spacecraft in the 1970's were not of sufficient resolution to show the effectiveness of gravity on Phobos in moving material down slopes.

    Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA

  15. Building identification from very high-resolution satellite images

    NASA Astrophysics Data System (ADS)

    Lhomme, Stephane

    Urbanisation still remains one of the main problems worldwide. The extent and rapidity of the urban growth induce a number of socio-economic and environmental conflicts everywhere. In order to reduce these problems, urban planners need to integrate spatial information in planning tools. Actually high expectations are made on Very High Spatial Resolution imagery (VHSR). These high-spatial resolution images are available at a reasonable price and due to short revisit periods, they offer a high degree of actuality. However, interpretation methods seem not to be adapted to this new type of images. The aim of our study is to develop a new method for semi-automatic building extraction with VHSR. The different steps performed to achieve our objective are each presented in a chapter. In the first chapter, the general context of our research is described with the definition of our objective. After a short historical review of urbanisation, we focus on urban growth and associated problems. In the following we discuss the possible contributions of geography to reduce these problems. After discussing concepts, theories and methodologies of geographical analysis in urban areas, we present existing general urban planning tools. Finally, we show the special interest of our study that is due to a growing need to integrate spatial information in these decision support tools. In the second chapter we verify the possibility of reaching our objective by analysing the technical characteristics of the images, the noise and the distortions which affect the images. Quality and interpretability of the studied image is analysed in order to show the capacity of these image to represent urban objects as close to reality as possible. The results confirm the potential of VHSR Imagery for urban objects analysis. The third chapter deal with the preliminary steps necessary for the elaboration of our method of building extraction. First, we evaluate the quality of the Sherbrooke Ikonos image

  16. Advanced DTM Generation from Very High Resolution Satellite Stereo Images

    NASA Astrophysics Data System (ADS)

    Perko, R.; Raggam, H.; Gutjahr, K. H.; Schardt, M.

    2015-03-01

    This work proposes a simple filtering approach that can be applied to digital surface models in order to extract digital terrain models. The method focusses on robustness and computational efficiency and is in particular tailored to filter DSMs that are extracted from satellite stereo images. It represents an evolution of an existing DTM generation method and includes distinct advancement through the integration of multi-directional processing as well as slope dependent filtering, thus denoted "MSD filtering". The DTM generation workflow is fully automatic and requires no user interaction. Exemplary results are presented for a DSM generated from a Pléiades tri-stereo image data set. Qualitative and quantitative evaluations with respect to highly accurate reference LiDAR data confirm the effectiveness of the proposed algorithm.

  17. Enhanced Beetle Luciferase for High-Resolution Bioluminescence Imaging

    PubMed Central

    Nakajima, Yoshihiro; Yamazaki, Tomomi; Nishii, Shigeaki; Noguchi, Takako; Hoshino, Hideto; Niwa, Kazuki; Viviani, Vadim R.; Ohmiya, Yoshihiro

    2010-01-01

    We developed an enhanced green-emitting luciferase (ELuc) to be used as a bioluminescence imaging (BLI) probe. ELuc exhibits a light signal in mammalian cells that is over 10-fold stronger than that of the firefly luciferase (FLuc), which is the most widely used luciferase reporter gene. We showed that ELuc produces a strong light signal in primary cells and tissues and that it enables the visualization of gene expression with high temporal resolution at the single-cell level. Moreover, we successfully imaged the nucleocytoplasmic shuttling of importin α by fusing ELuc at the intracellular level. These results demonstrate that the use of ELuc allows a BLI spatiotemporal resolution far greater than that provided by FLuc. PMID:20368807

  18. Adaptive Beamforming Algorithms for High Resolution Microwave Imaging

    DTIC Science & Technology

    1991-04-01

    Water pouring over the radomes covering some of the receivers could induce randot phase shifts to the waves passing through. Again, dynamic self... water tower, the power plant build- ing, and two connected storage silos. The microwave image of the white blocked area in the upper figure is shown...applying the MSA to the best set of three range bins; it reveals the two high stacks (A and B), the water tower (C), the two con- nected silos (D), and the

  19. Computer Model of a High-Resolution Imaging Sonar

    DTIC Science & Technology

    1990-07-01

    This is a very efficient method of obtaining imagcs in near-real-time. These sonars have found wide use in underwater vehicles and submersibles...perceived by an optical camera at the sonar location is generated by the method of range shading. This image serves as a reference for the subsequent efforts...Bhawan New Delhi, 110003 INDIA 10. Dr. V.P. Kodali Adviser Electronics Commission Lok Nayak Bhawan New Delhi, 110003 INDIA 11. Professor A.K. Jain

  20. High Resolution Imaging Using Phase Retrieval. Volume 2

    DTIC Science & Technology

    1991-10-01

    interferometer, then the modulus, but not the phase, of the Fourier transform of the object can be measured, despite the aberrations. We have developed and...analyzed phase retrieval algorithms that recover the unknown Fourier phase, which allows a fine-resolution image to be reconstructed despite the...THIS PAGE 19. Abstract (Continued) The theory of the amplitude interferometer was advanced and alternative estimators of the Fourier modulus (the

  1. High resolution and image processing of otoconia matrix

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.

    1993-01-01

    This study was designed to investigate patterns of fibrils organization in histochemically stained otoconia. Transmission electron microscope and video imaging were used. These data indicate that otoconia of the chick (Gallus domesticus) inner ear may have central cores in vivo. The data also show that the ultrastructural organization of fibrils fixed with aldehydes and histochemical stains follows trajectories that conform to the hexagonal shape of otoconia. These changes in direction may contribute to the formation of a central core. The existence of central cores is important for the in vivo buoyancy of otoconia. Packing of fibrils is tighter after phosphotungstic acid (PTA) stained otoconia than with other histochemical stains, which usually produce looser packing of fibrils and seemingly larger central core. TEM of tilted and untilted material showed that turning of fibrils occurs at the points where the face angles of otoconia form and where central cores exist. Video image processing of the images allowed reconstructing a template which, if assumed to repeat and change trajectories, would fit the pattern of fibrils seen in fixed otoconia. Since it is highly unlikely that aldehyde primary fixation or PTA stain caused such drastic change in the direction of fibrils, the template derived from these results may closely approximate patterns of otoconia fibrils packing in vivo. However, if the above is correct, the perfect crystallographic diffraction pattern of unfixed otoconia do not correspond to patterns of fixed fibrils.

  2. ERIS: the exoplanet high-resolution image simulator for CHARIS

    NASA Astrophysics Data System (ADS)

    Limbach, Mary Anne; Groff, Tyler D.; Kasdin, N. J.; Brandt, Timothy; Mede, Kyle; Loomis, Craig; Hayashi, Masahiko; Takato, Naruhisa

    2014-07-01

    ERIS is an image simulator for CHARIS, the high-contrast exoplanet integral field spectrograph (IFS) being built at Princeton University for the Subaru telescope. We present here the software design and implementation of the ERIS code. ERIS simulates CHARIS FITS images and data cubes that are used for developing the data reduction pipeline and verifying the expected CHARIS performance. Components of the software include detailed models of the light source (such as a star or exoplanet), atmosphere, telescope, adaptive optics systems (AO188 and SCExAO), CHARIS IFS and the Hawaii2-RG infrared detector. Code includes novel details such as the phase errors at the lenslet array, optical wavefront error maps and pinholes for reducing crosstalk, just to list a few. The details of the code as well as several simulated images are presented in this paper. This IFS simulator is critical for the CHARIS data analysis pipeline development, minimizing troubleshooting in the lab and on-sky and the characterization of crosstalk.

  3. High resolution and image processing of otoconia matrix

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.

    1993-01-01

    This study was designed to investigate patterns of fibrils organization in histochemically stained otoconia. Transmission electron microscope and video imaging were used. These data indicate that otoconia of the chick (Gallus domesticus) inner ear may have central cores in vivo. The data also show that the ultrastructural organization of fibrils fixed with aldehydes and histochemical stains follows trajectories that conform to the hexagonal shape of otoconia. These changes in direction may contribute to the formation of a central core. The existence of central cores is important for the in vivo buoyancy of otoconia. Packing of fibrils is tighter after phosphotungstic acid (PTA) stained otoconia than with other histochemical stains, which usually produce looser packing of fibrils and seemingly larger central core. TEM of tilted and untilted material showed that turning of fibrils occurs at the points where the face angles of otoconia form and where central cores exist. Video image processing of the images allowed reconstructing a template which, if assumed to repeat and change trajectories, would fit the pattern of fibrils seen in fixed otoconia. Since it is highly unlikely that aldehyde primary fixation or PTA stain caused such drastic change in the direction of fibrils, the template derived from these results may closely approximate patterns of otoconia fibrils packing in vivo. However, if the above is correct, the perfect crystallographic diffraction pattern of unfixed otoconia do not correspond to patterns of fixed fibrils.

  4. a Spatio-Spectral Camera for High Resolution Hyperspectral Imaging

    NASA Astrophysics Data System (ADS)

    Livens, S.; Pauly, K.; Baeck, P.; Blommaert, J.; Nuyts, D.; Zender, J.; Delauré, B.

    2017-08-01

    Imaging with a conventional frame camera from a moving remotely piloted aircraft system (RPAS) is by design very inefficient. Less than 1 % of the flying time is used for collecting light. This unused potential can be utilized by an innovative imaging concept, the spatio-spectral camera. The core of the camera is a frame sensor with a large number of hyperspectral filters arranged on the sensor in stepwise lines. It combines the advantages of frame cameras with those of pushbroom cameras. By acquiring images in rapid succession, such a camera can collect detailed hyperspectral information, while retaining the high spatial resolution offered by the sensor. We have developed two versions of a spatio-spectral camera and used them in a variety of conditions. In this paper, we present a summary of three missions with the in-house developed COSI prototype camera (600-900 nm) in the domains of precision agriculture (fungus infection monitoring in experimental wheat plots), horticulture (crop status monitoring to evaluate irrigation management in strawberry fields) and geology (meteorite detection on a grassland field). Additionally, we describe the characteristics of the 2nd generation, commercially available ButterflEYE camera offering extended spectral range (475-925 nm), and we discuss future work.

  5. High resolution fluorescent bio-imaging with electron beam excitation.

    PubMed

    Kawata, Yoshimasa; Nawa, Yasunori; Inami, Wataru

    2014-11-01

    We have developed electron beam excitation assisted (EXA) optical microscope[1-3], and demonstrated its resolution higher than 50 nm. In the microscope, a light source in a few nanometers size is excited by focused electron beam in a luminescent film. The microscope makes it possible to observe dynamic behavior of living biological specimens in various surroundings, such as air or liquids. Scan speed of the nanometric light source is faster than that in conventional near-field scanning optical microscopes. The microscope enables to observe optical constants such as absorption, refractive index, polarization, and their dynamic behavior on a nanometric scale. The microscope opens new microscopy applications in nano-technology and nano-science.Figure 1(a) shows schematic diagram of the proposed EXA microscope. An electron beam is focused on a luminescent film. A specimen is put on the luminescent film directly. The inset in Fig. 1(a) shows magnified image of the luminescent film and the specimen. Nanometric light source is excited in the luminescent film by the focused electron beam. The nanometric light source illuminates the specimen, and the scattered or transmitted radiation is detected with a photomultiplier tube (PMT). The light source is scanned by scanning of the focused electron beam in order to construct on image. Figure 1(b) shows a luminescence image of the cells acquired with the EXA microscope, and Fig. 1(c) shows a phase contrast microscope image. Cells were observed in culture solution without any treatments, such as fixation and drying. The shape of each cell was clearly recognized and some bright spots were observed in cells. We believe that the bright spots indicated with arrows were auto-fluorescence of intracellular granules and light- grey regions were auto-fluorescence of cell membranes. It is clearly demonstrated that the EXA microscope is useful tool for observation of living biological cells in physiological conditions.jmicro;63/suppl_1/i

  6. High Resolution Imaging of Io's Volcanoes with LBTI

    NASA Astrophysics Data System (ADS)

    Conrad, Al; Leisenring, Jarron; de Kleer, Katherine; Skemer, Andy; Hinz, Philip; Skrutskie, Michael; Veillet, Christian; de Pater, Imke; Bertero, Mario; Boccacci, Patrizia; Defrère, Denis; Hofmann, Karl-Heinz; La Camera, Andrea; Schertl, Dieter; Spencer, John; Weigelt, Gerd; Woodward, Charles E.

    2014-11-01

    The Large Binocular Telescope (LBT), located on Mount Graham in eastern Arizona, employs two 8.4 meter mirrors with a 14.4 center-to-center separation on a common mount. Coherent combination of these two AO-corrected apertures via the LBT Interferometer (LBTI) produces Fizeau interferometric images with spatial resolution consistent with the diffraction limit of the 22.8-meter aperture. In particular LBTI resolves thermal signatures (i.e., features observed at M-band) on the surface of Io down to ~150 kilometers; a two-fold improvement over what has previously been possible from the ground. We show images collected with LBTI on December 24, 2013, in which Loki's shape is clearly resolved and at least fourteen additional volcanic hot spots are detected.We analyze three locations in the LBTI data: emission features within Loki Patera, the area near Rarog and Heno Patarae, and a hot spot seen in the Colchis Regio.For Loki Patera, we interpret spatially resolved variation in the emission within that region. With M-band resolution that is comparable to what has previously been achievable only at K-band, we compare localized emission features with what has been seen in earlier observations at shorter wavelengths.Thermal emission from activity at Rarog and Heno Patarae is well resolved in these images, while a third hot-spot in the nearby Lerna Regio is also clearly resolved. This area is of special interest since it was the site of two high-effusion outbursts on August 15th, 2013 [de Pater et al. (2014) Icarus].Lastly, we explore a hot-spot seen in the Colchis Regio that may be a remnant of a violent outburst detected on August 29th, 2013 [de Kleer et al. (2014) Icarus].

  7. Bathymetric Extraction Using WORLDVIEW-2 High Resolution Images

    NASA Astrophysics Data System (ADS)

    Deidda, M.; Sanna, G.

    2012-07-01

    The fundamental principle underlying the methods used to extract bathymetric information from remote-sensed imagery is that different wavelengths of the solar light penetrate the water body to different depths. In order to extract bathymetric values from multispectral satellite imagery we implemented the Jupp method (Jupp, 1988), in IDL language and integrated it in the ENVI menu structure. In this experiment we apply this method to two images of the Poetto beach in Cagliari (Sardinia, Italy) acquired from the new-generation WorldView-2 sensor. Launched in October 2009, the WorldView-2 sensor provides, among others, one (named Coastal) that was designed specifically for this kind of analysis; we chose to use the Coastal band in place of the Blue one when applying the model. The images (a stereoscopic pair) were acquired on June 17, 2011. The 5419 scene was pre-processed in order to separate the sea bottom classes. This class was then georeferenced to overlap on the 5318 scene. A traditional bathymetric survey was performed, up to 1,50 m, planned and carried out in order to calibrate the model. For each scene, 10 calibration areas were selected, and for each of them a digital model of the sea bottom was generated. Precision and accuracy of the method were evaluated by analyzing the results extracted from the stereo-pairs and by examining the correlation between the surveyed depth values and the calculated ones, between the different models calculated from the same scene using different calibration areas, and between the models obtained from the two images.

  8. Monitoring plant growth using high resolution micro-CT images

    SciTech Connect

    Paquit, Vincent C; Gleason, Shaun Scott; Kalluri, Udaya C

    2011-01-01

    A multidisciplinary research conducted at the Oak Ridge National Laboratory aims at understanding the molecular controls of partitioning, transport and fate of carbon xed by photosynthesis in plants and its correlation with other measured plant system properties. Ultimately, we intend to develop a modeling framework to assess, correlate and predict as to which spatiotemporal changes in system dynamics are key to predicting emergent properties of system. Within this research, this paper relates to the quantitative morphological imaging of the main structures forming a plant (stem, roots, and leaves), their internal sub-structures, and changes occurring overtime.

  9. New High-Resolution Images of Summer Arctic Sea Ice

    NASA Astrophysics Data System (ADS)

    Kwok, Ronald; Untersteiner, Norbert

    2011-02-01

    In 1995 a group of government and academic scientists were appointed by the vice president of the United States to review and advise on acquisitions of imagery obtained by classified intelligence satellites (National Technical Means) and to recommend the declassification of certain data sets for the benefit of science. The group is called MEDEA and was first described by Richelson [1998]. MEDEA disbanded in 2000 but reassembled in 2008. On 15 June 2009, under the auspices of MEDEA, the U.S. Geological Survey (USGS) released to the public as Literal Image Derived Products (LIDPs) numerous images with 1-meter resolution acquired since 1999 at six locations in the Arctic Basin (Beaufort Sea, Canadian Arctic, Fram Strait, East Siberian Sea, Chukchi Sea, and Point Barrow). These locations are named “fiducial sites” to suggest that the collected imagery establishes a baseline data set for understanding recent and future changes. Data in the Global Fiducials Library (GFL) can be accessed via http://gfl.usgs.gov/. This data repository is updated by USGS as additional data become available.

  10. Fast and high resolution single-cell BRET imaging

    PubMed Central

    Goyet, Elise; Bouquier, Nathalie; Ollendorff, Vincent; Perroy, Julie

    2016-01-01

    Resonance Energy Transfer (RET)-based technologies are used to report protein-protein interactions in living cells. Among them, Bioluminescence-initiated RET (BRET) provides excellent sensitivity but the low light intensity intrinsic to the bioluminescent process hampers its use for the localization of protein complexes at the sub-cellular level. Herein we have characterized the methodological conditions required to reliably perform single-cell BRET imaging using an extremely bright luciferase, Nanoluciferase (Nluc). With this, we achieved an unprecedented performance in the field of protein-protein interaction imaging in terms of temporal and spatial resolution, duration of signal stability, signal sensitivity and dynamic range. As proof-of-principle, an Nluc-containing BRET-based sensor of ERK activity enabled the detection of subtle, transient and localized variations in ERK activity in neuronal dendritic spines, induced by the activation of endogenous synaptic NMDA receptors. This development will improve our comprehension of both the spatio-temporal dynamics of protein-protein interactions and the activation patterns of specific signaling pathways. PMID:27302735

  11. High Resolution HST Images of Pluto and Charon

    NASA Astrophysics Data System (ADS)

    1994-05-01

    At the Edge of the Solar System Click here to jump to photo. The remote planet Pluto and its moon Charon orbit the Sun at a mean distance of almost 6,000 million kilometres, or nearly fourty times farther out than the Earth. During a recent investigation by an international group of astronomers [1], the best picture ever of Pluto and Charon [2] was secured with the European Space Agency's Faint Object Camera at the Hubble Space Telescope (HST). It shows the two objects as individual disks, and it is likely that further image enhancement will allow us to see surface features on Pluto. A Very Special Pair of Celestial Objects Almost all the known facts about these two bodies show that they are quite unusual: Pluto's orbit around the Sun is much more elongated and more inclined to the main plane of the Solar System than that of any other major planet; Charon's orbit around Pluto is nearly perpendicular to this plane; their mutual distance is amazingly small when compared to their size; Charon is half the size of Pluto and the ratio of their masses is much closer to unity than is the case for all other planets and their moons. Moreover, both are small and solid bodies, in contrast to the other, large and gaseous planets in the outer Solar System. We do not know why this is so. But there is another important aspect which makes Pluto and Charon even more interesting: at this very large distance from the Sun, any evolutionary changes happen very slowly. It is therefore likely that Pluto and Charon hold important clues to the conditions that prevailed in the early Solar System and thus to the origin and the evolution of the Solar System as a whole. Long and Difficult Analysis Ahead The present image shows that the overall quality of the new data obtained with the ESA Faint Object Camera on the refurbished Hubble Space Telescope is extremely good. However, such an image represents only the first step of a subsequent, detailed analysis with the ultimate goal of determining

  12. New High Sensitivity, High Resolution Dual Color Calibrated Imaging Radiometer

    NASA Astrophysics Data System (ADS)

    Silver, Alan; Carlen, Frank R.; Zegel, Ferdinand H.

    1988-07-01

    A dual color calibrated imaging radiometer is being developed by Magnavox under government sponsorship to provide background and signature data and ground truth for the Automatic Target Recognizer (ATR) community. The system features high spatial and thermal resolution to be consistent with second generation imaging systems using currently available technology. Special design features are incorporated to yield accurate apparent temperature readings in both the 3-5 and 8-12 micron regions with pixel to pixel registration. The system consists of a fully militarized sensor head and remote processing electronics containing a mixture of customized and commercial processing equipment. The electronics may be up to 150 feet from the sensor head. The system output consists of two simultaneous video signals, one for each color. The videos are available in both an RS-170 format and an ATRWG digital format. The system produces 12 bit video. The video of each channel is analyzed by a dedicated microcomputer to provide real time data reduction to the operator.

  13. High resolution hyperspectral imaging with a high throughput virtual slit

    NASA Astrophysics Data System (ADS)

    Gooding, Edward A.; Gunn, Thomas; Cenko, Andrew T.; Hajian, Arsen R.

    2016-05-01

    Hyperspectral imaging (HSI) device users often require both high spectral resolution, on the order of 1 nm, and high light-gathering power. A wide entrance slit assures reasonable étendue but degrades spectral resolution. Spectrometers built using High Throughput Virtual Slit™ (HTVS) technology optimize both parameters simultaneously. Two remote sensing use cases that require high spectral resolution are discussed. First, detection of atmospheric gases with intrinsically narrow absorption lines, such as hydrocarbon vapors or combustion exhaust gases such as NOx and CO2. Detecting exhaust gas species with high precision has become increasingly important in the light of recent events in the automobile industry. Second, distinguishing reflected daylight from emission spectra in the visible and NIR (VNIR) regions is most easily accomplished using the Fraunhofer absorption lines in solar spectra. While ground reflectance spectral features in the VNIR are generally quite broad, the Fraunhofer lines are narrow and provide a signature of intrinsic vs. extrinsic illumination. The High Throughput Virtual Slit enables higher spectral resolution than is achievable with conventional spectrometers by manipulating the beam profile in pupil space. By reshaping the instrument pupil with reflective optics, HTVS-equipped instruments create a tall, narrow image profile at the exit focal plane, typically delivering 5X or better the spectral resolution achievable with a conventional design.

  14. IRAC Snapshot Imaging of Red Herschel Galaxies

    NASA Astrophysics Data System (ADS)

    Cooray, Asantha; Nayyeri, Hooshang; Wardlow, Julie; Ivison, Rob; Perez-Fournon, Ismael; Riechers, Dominik; Clements, David; Oliver, Seb; Oteo, Ivan

    2016-08-01

    Wide-field submillimeter surveys with Herschel have produced large samples of rare populations, which provide some of the most stringent constraints on galaxy formation theories. In this proposal we request IRAC observations of 'red' Herschel sources, which are the most extreme DSFGs at z>4. The proposed snapshot IRAC 3.6 and 4.5um data will probe the stellar emission from these systems - complementary data to the far-infrared dust emission that led to their identification. We will use these data to extend the SEDs into the near-IR regime and measure more reliable stellar masses than otherwise available. They will be combined with existing survey data and dedicated follow-up programs to map the evolution of DSFGs as a function of redshift, stellar mass and far-IR luminosity.

  15. High resolution neutron imaging of water in PEM fuel cells

    SciTech Connect

    Mukundan, Rangachary; Borup, Rodney L; Davey, John R; Spendelow, Jacob S

    2008-01-01

    Optimal water management in Polymer Electrolyte Membrane (PEM) fuel cells is critical to improving the performance and durability of fuel cell systems especially during transient, start-up and shut-down operations. For example, while a high water content is desirable for improved membrane and catalyst ionomer conductivity, high water content can also block gas access to the triple-phase boundary resulting in lowered performance due to catalyst and gas diffusion layer (GDL) flooding. Visualizing liquid water by neutron imaging has been used over the past decade to study the water distribution inside operating fuel cells. In this paper, the results from our imaging at NIST using their recently installed higher resolution ({approx} 25 mm) Microchannel Plate (MCP) detector with a pixel pitch of 14.7 mm are presented. This detector is capable of quantitatively imaging the water inside the MEA (Membrane Electrode Assembly)/GDL (Gas Diffusion Layer) of working fuel cells and can provide the water profiles within these various components in addition to the channel water. Specially designed fuel cells (active area = 2.25 cm{sup 2}) have been used in order to take advantage of the full detector resolution. The cell design is illustrated in a figure where one of the current collector/end plates is shown. The serpentine pattern was machined into a block of aluminum and plated with nickel and then gold to form the flow field. The measurements were performed using beam no. 1 and aperture no. 2 with a fluence rate of 1.9 x 10{sup 6} neutrons cm{sup -2} sec{sup -1}. The cells were assembled with Gore{sup TM} Primea{sup R} MEAs and SGL Sigracet {sup R} 24 series GDLs (PRIMEA, GORE-SELECT and GORE are trademarks of W. L. Gore & Associates, Inc). All the cells were tested at 80 {sup o}C with 1.2 stoichiometry H{sub 2} and 2.0 stoichiometry air flows.

  16. High resolution LBT imaging of Io and Jupiter

    NASA Astrophysics Data System (ADS)

    Conrad, A.; de Kleer, K.; Leisenring, J.; La Camera, A.; Arcidiacono, C.; Bertero, M.; Boccacci, P.; Defrère, D.; de Pater, I.; Hinz, P.; Hoffman, K.-H.; Kürster, M.; Rathbun, J.; Schertl, D.; Skemer, A.; Skrutskie, M.; Spencer, J.; Veillet, C.; Weigelt, G.; Woodward, C.

    2015-10-01

    We report here results from observing Io at high angular resolution, ˜32 mas at 4.8 μm, with LBT at two favorable oppositions as described in our report given at the 2011 EPSC [1]. Analysis of datasets acquired during the last two oppositions has yielded spatially resolved M-band emission at Loki Patera [2], L-band fringes at an eruption site, an occultation of Loki and Pele by Europa, and sufficient sub-earth longitude (SEL) and parallactic angle coverage to produce a full disk map.We summarize completed results for the first of these, and give brief progress reports for the latter three. Finally, we provide plans for imaging the full disk of Jupiter using the MCAO system which is in its commissioning phase at LBT.

  17. Accuracy Analysis on Large Blocks of High Resolution Images

    NASA Technical Reports Server (NTRS)

    Passini, Richardo M.

    2007-01-01

    Although high altitude frequencies effects are removed at the time of basic image generation, low altitude (Yaw) effects are still present in form of affinity/angular affinity. They are effectively removed by additional parameters. Bundle block adjustment based on properly weighted ephemeris/altitude quaternions (BBABEQ) are not enough to remove the systematic effect. Moreover, due to the narrow FOV of the HRSI, position and altitude are highly correlated making it almost impossible to separate and remove their systematic effects without extending the geometric model (Self-Calib.) The systematic effects gets evident on the increase of accuracy (in terms of RMSE at GCPs) for looser and relaxed ground control at the expense of large and strong block deformation with large residuals at check points. Systematic errors are most freely distributed and their effects propagated all over the block.

  18. Nanedi Vallis: Sustained Water Flow? - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This picture of a canyon on the Martian surface was obtained a few minutes after 10 PM PST, January 8, 1998 by the Mars Orbiter Camera (MOC), during the 87th orbit around Mars of the Mars Global Surveyor spacecraft. It shows the canyon of Nanedi Vallis, one of the Martian valley systems cutting through cratered plains in the Xanthe Terra region of Mars. The picture covers an area 9.8 km by 18.5 km (6.1 mi by 11.5 mi), and features as small as 12 m (39 ft) can be seen. The canyon is about 2.5 km (1.6 mi) wide. Rocky outcrops are found along the upper canyon walls; weathered debris found on the lower canyon slopes and along the canyon floor. The origin of this canyon is enigmatic: some features, such as terraces within the canyon (as seen near the top of the frame) and the small 200 m (660 ft) wide channel (also seen near the top of the frame) suggest continual fluid flow and downcutting. Other features, such as the lack of a contributing pattern of smaller channels on the surface surrounding the canyon, box-headed tributaries, and the size and tightness of the apparent meanders (as seen, for example, in the Viking image 89A32), suggest formation by collapse. It is likely that both continual flow and collapse have been responsible for the canyon as it now appears. Further observations, especially in areas west of the present image, will be used to help separate the relative effects of these and other potential formation and modification processes.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  19. High Resolution MALDI Imaging Mass Spectrometry of Retinal Tissue Lipids

    PubMed Central

    Anderson, David M. G.; Ablonczy, Zsolt; Koutalos, Yiannis; Spraggins, Jeffrey; Crouch, Rosalie K.; Caprioli, Richard M.; Schey, Kevin L.

    2014-01-01

    Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has the ability to provide an enormous amount of information on the abundances and spatial distributions of molecules within biological tissues. The rapid progress in the development of this technology significantly improves our ability to analyze smaller and smaller areas and features within tissues. The mammalian eye has evolved over millions of years to become an essential asset for survival, providing important sensory input of an organism’s surroundings. The highly complex sensory retina of the eye is comprised of numerous cell types organized into specific layers with varying dimensions, the thinnest of which is the 10 μm retinal pigment epithelium (RPE). This single cell layer and the photoreceptor layer contain the complex biochemical machinery required to convert photons of light into electrical signals that are transported to the brain by axons of retinal ganglion cells. Diseases of the retina including age related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy occur when the functions of these cells are interrupted by molecular processes that are not fully understood. In this report, we demonstrate the use of high spatial resolution MALDI IMS and FT-ICR tandem mass spectrometry in the Abca4−/− knockout mouse model of Stargardt disease, a juvenile onset form of macular degeneration. The spatial distributions and identity of lipid and retinoid metabolites are shown to be unique to specific retinal cell layers. PMID:24819461

  20. High resolution spectroscopic imaging of GABA at 3 Tesla.

    PubMed

    Zhu, He; Edden, Richard A E; Ouwerkerk, Ronald; Barker, Peter B

    2011-03-01

    A spin echo-based MRSI sequence was developed to acquire edited spectra of γ-aminobutyric acid in an entire slice. Water and lipid signals were suppressed by a dual-band presaturation sequence, which included integrated outer volume suppression pulses for additional lipid suppression. Experiments in three normal volunteers were performed at 3 T using a 32-channel head coil. High signal-to-noise ratio spectra and metabolic images of γ-aminobutyric acid were acquired from nominal 4.5 cm3 voxels (estimated actual voxel size 7.0 cm3) in a scan time of 17 min. The sequence is also expected to co-edit homocarnosine and macromolecules, giving a composite γ-aminobutyric acid+ resonance. The γ-aminobutyric acid+ to water ratio was measured using a companion water MRSI scan and was found to correlate linearly with the % gray matter (GM) of each voxel (γ-aminobutyric acid+/water=(1.5×GM+3.2)×10(-5), R=0.27), with higher γ-aminobutyric acid+ levels in gray matter compared with white. In conclusion, high signal-to-noise ratio γ-aminobutyric acid-MRSI is possible at 3 T within clinically feasible scan times. Copyright © 2010 Wiley-Liss, Inc.

  1. High Resolution Spectroscopic Imaging of GABA at 3 Tesla

    PubMed Central

    Zhu, He; Edden, Richard A. E.; Ouwerkerk, Ronald; Barker, Peter B.

    2011-01-01

    A spin echo-based MRSI sequence was developed to acquire edited spectra of γ-aminobutyric acid in an entire slice. Water and lipid signals were suppressed by a dual-band presaturation sequence, which included integrated outer volume suppression pulses for additional lipid suppression. Experiments in three normal volunteers were performed at 3 T using a 32-channel head coil. High signal-to-noise ratio spectra and metabolic images of γ-aminobutyric acid were acquired from nominal 4.5 cm3 voxels (estimated actual voxel size 7.0 cm3) in a scan time of 17 min. The sequence is also expected to co-edit homocarnosine and macromolecules, giving a composite γ-aminobutyric acid+ resonance. The γ-aminobutyric acid+ to water ratio was measured using a companion water MRSI scan and was found to correlate linearly with the % gray matter (GM) of each voxel (γ-aminobutyric acid+/water = (1.5 × GM + 3.2) × 10−5, R = 0.27), with higher γ-aminobutyric acid+ levels in gray matter compared with white. In conclusion, high signal-to-noise ratio γ-aminobutyric acid-MRSI is possible at 3 T within clinically feasible scan times. PMID:21337399

  2. High resolution MALDI imaging mass spectrometry of retinal tissue lipids.

    PubMed

    Anderson, David M G; Ablonczy, Zsolt; Koutalos, Yiannis; Spraggins, Jeffrey; Crouch, Rosalie K; Caprioli, Richard M; Schey, Kevin L

    2014-08-01

    Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has the ability to provide an enormous amount of information on the abundances and spatial distributions of molecules within biological tissues. The rapid progress in the development of this technology significantly improves our ability to analyze smaller and smaller areas and features within tissues. The mammalian eye has evolved over millions of years to become an essential asset for survival, providing important sensory input of an organism's surroundings. The highly complex sensory retina of the eye is comprised of numerous cell types organized into specific layers with varying dimensions, the thinnest of which is the 10 μm retinal pigment epithelium (RPE). This single cell layer and the photoreceptor layer contain the complex biochemical machinery required to convert photons of light into electrical signals that are transported to the brain by axons of retinal ganglion cells. Diseases of the retina, including age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy, occur when the functions of these cells are interrupted by molecular processes that are not fully understood. In this report, we demonstrate the use of high spatial resolution MALDI IMS and FT-ICR tandem mass spectrometry in the Abca4(-/-) knockout mouse model of Stargardt disease, a juvenile onset form of macular degeneration. The spatial distributions and identity of lipid and retinoid metabolites are shown to be unique to specific retinal cell layers.

  3. High Resolution MALDI Imaging Mass Spectrometry of Retinal Tissue Lipids

    NASA Astrophysics Data System (ADS)

    Anderson, David M. G.; Ablonczy, Zsolt; Koutalos, Yiannis; Spraggins, Jeffrey; Crouch, Rosalie K.; Caprioli, Richard M.; Schey, Kevin L.

    2014-08-01

    Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has the ability to provide an enormous amount of information on the abundances and spatial distributions of molecules within biological tissues. The rapid progress in the development of this technology significantly improves our ability to analyze smaller and smaller areas and features within tissues. The mammalian eye has evolved over millions of years to become an essential asset for survival, providing important sensory input of an organism's surroundings. The highly complex sensory retina of the eye is comprised of numerous cell types organized into specific layers with varying dimensions, the thinnest of which is the 10 μm retinal pigment epithelium (RPE). This single cell layer and the photoreceptor layer contain the complex biochemical machinery required to convert photons of light into electrical signals that are transported to the brain by axons of retinal ganglion cells. Diseases of the retina, including age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy, occur when the functions of these cells are interrupted by molecular processes that are not fully understood. In this report, we demonstrate the use of high spatial resolution MALDI IMS and FT-ICR tandem mass spectrometry in the Abca4 -/- knockout mouse model of Stargardt disease, a juvenile onset form of macular degeneration. The spatial distributions and identity of lipid and retinoid metabolites are shown to be unique to specific retinal cell layers.

  4. High-Resolution Large-Field-of-View Ultrasound Breast Imager

    DTIC Science & Technology

    2014-08-01

    Ultrasound Breast Imager PRINCIPAL INVESTIGATOR: Patrick LaRiviere CONTRACTING...May 2014 4. TITLE AND SUBTITLE High-Resolution Large-Field-of-View Ultrasound Breast Imager 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11...work, we sought to construct and test the first practical full-field transmission ultrasound breast imaging system. The system will ultimately have a

  5. Information Extraction of High Resolution Remote Sensing Images Based on the Calculation of Optimal Segmentation Parameters.

    PubMed

    Zhu, Hongchun; Cai, Lijie; Liu, Haiying; Huang, Wei

    2016-01-01

    Multi-scale image segmentation and the selection of optimal segmentation parameters are the key processes in the object-oriented information extraction of high-resolution remote sensing images. The accuracy of remote sensing special subject information depends on this extraction. On the basis of WorldView-2 high-resolution data, the optimal segmentation parameters methodof object-oriented image segmentation and high-resolution image information extraction, the following processes were conducted in this study. Firstly, the best combination of the bands and weights was determined for the information extraction of high-resolution remote sensing image. An improved weighted mean-variance method was proposed andused to calculatethe optimal segmentation scale. Thereafter, the best shape factor parameter and compact factor parameters were computed with the use of the control variables and the combination of the heterogeneity and homogeneity indexes. Different types of image segmentation parameters were obtained according to the surface features. The high-resolution remote sensing images were multi-scale segmented with the optimal segmentation parameters. Ahierarchical network structure was established by setting the information extraction rules to achieve object-oriented information extraction. This study presents an effective and practical method that can explain expert input judgment by reproducible quantitative measurements. Furthermore the results of this procedure may be incorporated into a classification scheme.

  6. Information Extraction of High Resolution Remote Sensing Images Based on the Calculation of Optimal Segmentation Parameters

    PubMed Central

    Zhu, Hongchun; Cai, Lijie; Liu, Haiying; Huang, Wei

    2016-01-01

    Multi-scale image segmentation and the selection of optimal segmentation parameters are the key processes in the object-oriented information extraction of high-resolution remote sensing images. The accuracy of remote sensing special subject information depends on this extraction. On the basis of WorldView-2 high-resolution data, the optimal segmentation parameters methodof object-oriented image segmentation and high-resolution image information extraction, the following processes were conducted in this study. Firstly, the best combination of the bands and weights was determined for the information extraction of high-resolution remote sensing image. An improved weighted mean-variance method was proposed andused to calculatethe optimal segmentation scale. Thereafter, the best shape factor parameter and compact factor parameters were computed with the use of the control variables and the combination of the heterogeneity and homogeneity indexes. Different types of image segmentation parameters were obtained according to the surface features. The high-resolution remote sensing images were multi-scale segmented with the optimal segmentation parameters. Ahierarchical network structure was established by setting the information extraction rules to achieve object-oriented information extraction. This study presents an effective and practical method that can explain expert input judgment by reproducible quantitative measurements. Furthermore the results of this procedure may be incorporated into a classification scheme. PMID:27362762

  7. Retrieving high-resolution images over the Internet from an anatomical image database

    NASA Astrophysics Data System (ADS)

    Strupp-Adams, Annette; Henderson, Earl

    1999-12-01

    The Visible Human Data set is an important contribution to the national collection of anatomical images. To enhance the availability of these images, the National Library of Medicine has supported the design and development of a prototype object-oriented image database which imports, stores, and distributes high resolution anatomical images in both pixel and voxel formats. One of the key database modules is its client-server Internet interface. This Web interface provides a query engine with retrieval access to high-resolution anatomical images that range in size from 100KB for browser viewable rendered images, to 1GB for anatomical structures in voxel file formats. The Web query and retrieval client-server system is composed of applet GUIs, servlets, and RMI application modules which communicate with each other to allow users to query for specific anatomical structures, and retrieve image data as well as associated anatomical images from the database. Selected images can be downloaded individually as single files via HTTP or downloaded in batch-mode over the Internet to the user's machine through an applet that uses Netscape's Object Signing mechanism. The image database uses ObjectDesign's object-oriented DBMS, ObjectStore that has a Java interface. The query and retrieval systems has been tested with a Java-CDE window system, and on the x86 architecture using Windows NT 4.0. This paper describes the Java applet client search engine that queries the database; the Java client module that enables users to view anatomical images online; the Java application server interface to the database which organizes data returned to the user, and its distribution engine that allow users to download image files individually and/or in batch-mode.

  8. Single photon imaging at ultra-high resolution

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Spandre, G.; Minuti, M.; Brez, A.; Baldini, L.; Latronico, L.; Omodei, N.; Sgrò, C.; Bregeon, J.; Razzano, M.; Pinchera, M.; Tremsin, A.; McPhate, J.; Vallerga, J. V.; Siegmund, O.

    2008-06-01

    We present a detection system capable of imaging both single photon/positive ion and multiple coincidence photons/positive ions with extremely high spatial resolution. In this detector the photoelectrons excited by the incoming photons are multiplied by microchannel plate(s) (MCP). The process of multiplication is spatially constrained within an MCP pore, which can be as small as 4 μm for commercially available MCPs. An electron cloud originated by a single photoelectron is then encoded by a pixellated custom analog ASIC consisting of 105 K charge sensitive pixels of 50 μm in size arranged on a hexagonal grid. Each pixel registers the charge with an accuracy of <100 electrons rms. Computation of the event centroid from the readout charges results in an accurate event position. A large number of simultaneous photons spatially separated by ˜0.4 mm can be detected simultaneously allowing multiple coincidence operation for the experiments where a large number of incoming photons/positive ions have to be detected simultaneously. The experimental results prove that the spatial resolution of the readout system itself is ˜3 μm FWHM enabling detection resolution better than 6 μm for the small pore MCPs. An attractive feature of the detection system is its capability to register the timing of each incoming photon/positive ion (in single photon detection mode) or of the first incoming particle (for the multiple coincidence detection) with an accuracy of ˜130 ps FWHM. There is also virtually no dark count noise in the detection system making it suitable for low count rate applications.

  9. Computational high-resolution optical imaging of the living human retina

    NASA Astrophysics Data System (ADS)

    Shemonski, Nathan D.; South, Fredrick A.; Liu, Yuan-Zhi; Adie, Steven G.; Scott Carney, P.; Boppart, Stephen A.

    2015-07-01

    High-resolution in vivo imaging is of great importance for the fields of biology and medicine. The introduction of hardware-based adaptive optics (HAO) has pushed the limits of optical imaging, enabling high-resolution near diffraction-limited imaging of previously unresolvable structures. In ophthalmology, when combined with optical coherence tomography, HAO has enabled a detailed three-dimensional visualization of photoreceptor distributions and individual nerve fibre bundles in the living human retina. However, the introduction of HAO hardware and supporting software adds considerable complexity and cost to an imaging system, limiting the number of researchers and medical professionals who could benefit from the technology. Here we demonstrate a fully automated computational approach that enables high-resolution in vivo ophthalmic imaging without the need for HAO. The results demonstrate that computational methods in coherent microscopy are applicable in highly dynamic living systems.

  10. High Resolution X-Ray Phase Contrast Imaging With Acoustic Tissue-Selective Contrast Enhancement

    DTIC Science & Technology

    2006-06-01

    microfocus x - ray source. Rev. Sci. Instr. 68, 2774 (1997). 8. Krol, A. et al. Laser-based microfocused x - ray source for mammography: Feasibility study...W81XWH-04-1-0481 TITLE: High Resolution X - ray Phase Contrast Imaging With Acoustic Tissue-Selective Contrast Enhancement PRINCIPAL...REPORT TYPE Annual 3. DATES COVERED (From - To) 1 Jun 2005 – 31 May 2006 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER High Resolution X - ray

  11. High-resolution imaging of compact high-velocity clouds

    NASA Astrophysics Data System (ADS)

    de Heij, V.; Braun, R.; Burton, W. B.

    2002-08-01

    We have imaged five compact high-velocity clouds in H I with arcmin angular resolution and km s-1 spectral resolution using the Westerbork Synthesis Radio Telescope. These CHVCs have a characteristic morphology, consisting of one or more quiescent, low-dispersion compact cores embedded in a diffuse warm halo. The compact cores can be unambiguously identified with the cool neutral medium of condensed atomic hydrogen, since their linewidths are significantly narrower than the thermal linewidth of the warm neutral medium. Because of the limited sensitivity to diffuse emission inherent to interferometric data, the warm medium is not directly detected in the WSRT observations. Supplementary total-power data, which is fully sensitive to both the cool and warm components of H I, is available for comparison for all the sources, albeit with angular resolutions that vary from 3' to 36'. The fractional H I flux in compact CNM components varies from 4% to 16% in our sample. All objects have at least one local peak in the CNM column density which exceeds about 1019;cm-2 when observed with arcmin resolution. It is plausible that a peak column density of 1-2 x 1019;cm-2 is a prerequisite for the long-term survival of these sources. One object in our sample, CHVC 120-20-443 (Davies' cloud), lies in close projected proximity to the disk of M 31. This object is characterized by exceptionally broad linewidths in its CNM concentrations, more than 5 times greater than the median value found in the 13 CHVCs studied to date at comparable resolution. These CNM concentrations lie in an arc on the edge of the source facing the M 31 disk. The diffuse H I component of this source, seen in total-power data from the NRAO 140-foot telescope, has a positional offset in the direction of the M 31 disk. All of these attributes suggest that CHVC 120-20-443 is in a different evolutionary state than most of the other CHVCs which have been studied. Similarly broad CNM linewidths have only been detected

  12. Experimental validation of a high-resolution diffuse optical imaging modality: photomagnetic imaging

    NASA Astrophysics Data System (ADS)

    Nouizi, Farouk; Luk, Alex; Thayer, Dave; Lin, Yuting; Ha, Seunghoon; Gulsen, Gultekin

    2016-01-01

    We present experimental results that validate our imaging technique termed photomagnetic imaging (PMI). PMI illuminates the medium under investigation with a near-infrared light and measures the induced temperature increase using magnetic resonance imaging. A multiphysics solver combining light and heat propagation is used to model spatiotemporal distribution of temperature increase. Furthermore, a dedicated PMI reconstruction algorithm has been developed to reveal high-resolution optical absorption maps from temperature measurements. Being able to perform measurements at any point within the medium, PMI overcomes the limitations of conventional diffuse optical imaging. We present experimental results obtained on agarose phantoms mimicking biological tissue with inclusions having either different sizes or absorption contrasts, located at various depths. The reconstructed images show that PMI can successfully resolve these inclusions with high resolution and recover their absorption coefficient with high-quantitative accuracy. Even a 1-mm inclusion located 6-mm deep is recovered successfully and its absorption coefficient is underestimated by only 32%. The improved PMI system presented here successfully operates under the maximum skin exposure limits defined by the American National Standards Institute, which opens up the exciting possibility of its future clinical use for diagnostic purposes.

  13. Experimental validation of a high-resolution diffuse optical imaging modality: photomagnetic imaging

    PubMed Central

    Nouizi, Farouk; Luk, Alex; Thayer, Dave; Lin, Yuting; Ha, Seunghoon; Gulsen, Gultekin

    2016-01-01

    Abstract. We present experimental results that validate our imaging technique termed photomagnetic imaging (PMI). PMI illuminates the medium under investigation with a near-infrared light and measures the induced temperature increase using magnetic resonance imaging. A multiphysics solver combining light and heat propagation is used to model spatiotemporal distribution of temperature increase. Furthermore, a dedicated PMI reconstruction algorithm has been developed to reveal high-resolution optical absorption maps from temperature measurements. Being able to perform measurements at any point within the medium, PMI overcomes the limitations of conventional diffuse optical imaging. We present experimental results obtained on agarose phantoms mimicking biological tissue with inclusions having either different sizes or absorption contrasts, located at various depths. The reconstructed images show that PMI can successfully resolve these inclusions with high resolution and recover their absorption coefficient with high-quantitative accuracy. Even a 1-mm inclusion located 6-mm deep is recovered successfully and its absorption coefficient is underestimated by only 32%. The improved PMI system presented here successfully operates under the maximum skin exposure limits defined by the American National Standards Institute, which opens up the exciting possibility of its future clinical use for diagnostic purposes. PMID:26790644

  14. Application of Convolutional Neural Network in Classification of High Resolution Agricultural Remote Sensing Images

    NASA Astrophysics Data System (ADS)

    Yao, C.; Zhang, Y.; Zhang, Y.; Liu, H.

    2017-09-01

    With the rapid development of Precision Agriculture (PA) promoted by high-resolution remote sensing, it makes significant sense in management and estimation of agriculture through crop classification of high-resolution remote sensing image. Due to the complex and fragmentation of the features and the surroundings in the circumstance of high-resolution, the accuracy of the traditional classification methods has not been able to meet the standard of agricultural problems. In this case, this paper proposed a classification method for high-resolution agricultural remote sensing images based on convolution neural networks(CNN). For training, a large number of training samples were produced by panchromatic images of GF-1 high-resolution satellite of China. In the experiment, through training and testing on the CNN under the toolbox of deep learning by MATLAB, the crop classification finally got the correct rate of 99.66 % after the gradual optimization of adjusting parameter during training. Through improving the accuracy of image classification and image recognition, the applications of CNN provide a reference value for the field of remote sensing in PA.

  15. High-resolution far-field ghost imaging via sparsity constraint

    PubMed Central

    Gong, Wenlin; Han, Shensheng

    2015-01-01

    Ghost imaging (GI) is a method to nonlocally image an object with a single-pixel detector. However, the speckle's transverse size at the object plane limits the system's imaging resolution for conventional GI linear reconstruction algorithm. By combining the sparsity constraint of imaging object with ghost imaging method, we demonstrate experimentally that ghost imaging via sparsity constraint (GISC) can dramatically enhance the imaging resolution even using the random measurements far below the Nyquist limit. The image reconstruction algorithm of GISC is based on compressive sensing. Factors affecting the reconstruction quality of high-resolution GISC, such as the receiving system's numerical aperture and the object's sparse representation basis, are also investigated experimentally. This high-resolution imaging technique will have great applications in the microscopy and remote-sensing areas. PMID:25787897

  16. Snapshot Imaging Spectrometry in the Visible and Long Wave Infrared

    NASA Astrophysics Data System (ADS)

    Maione, Bryan David

    Imaging spectrometry is an optical technique in which the spectral content of an object is measured at each location in space. The main advantage of this modality is that it enables characterization beyond what is possible with a conventional camera, since spectral information is generally related to the chemical composition of the object. Due to this, imaging spectrometers are often capable of detecting targets that are either morphologically inconsistent, or even under resolved. A specific class of imaging spectrometer, known as a snapshot system, seeks to measure all spatial and spectral information simultaneously, thereby rectifying artifacts associated with scanning designs, and enabling the measurement of temporally dynamic scenes. Snapshot designs are the focus of this dissertation. Three designs for snapshot imaging spectrometers are developed, each providing novel contributions to the field of imaging spectrometry. In chapter 2, the first spatially heterodyned snapshot imaging spectrometer is modeled and experimentally validated. Spatial heterodyning is a technique commonly implemented in non-imaging Fourier transform spectrometry. For Fourier transform imaging spectrometers, spatial heterodyning improves the spectral resolution trade space. Additionally, in this chapter a unique neural network based spectral calibration is developed and determined to be an improvement beyond Fourier and linear operator based techniques. Leveraging spatial heterodyning as developed in chapter 2, in chapter 3, a high spectral resolution snapshot Fourier transform imaging spectrometer, based on a Savart plate interferometer, is developed and experimentally validated. The sensor presented in this chapter is the highest spectral resolution sensor in its class. High spectral resolution enables the sensor to discriminate narrowly spaced spectral lines. The capabilities of neural networks in imaging spectrometry are further explored in this chapter. Neural networks are used to

  17. Interactive Display of High-Resolution Images on the World Wide Web.

    ERIC Educational Resources Information Center

    Clyde, Stephen W.; Hirschi, Gregory W.

    Viewing high-resolution images on the World Wide Web at a level of detail necessary for collaborative research is still a problem today, given the Internet's current bandwidth limitations and its ever increasing network traffic. ImageEyes is an interactive display tool being developed at Utah State University that addresses this problem by…

  18. A high-resolution airborne four-camera imaging system for agricultural remote sensing

    USDA-ARS?s Scientific Manuscript database

    This paper describes the design and testing of an airborne multispectral digital imaging system for remote sensing applications. The system consists of four high resolution charge coupled device (CCD) digital cameras and a ruggedized PC equipped with a frame grabber and image acquisition software. T...

  19. High-resolution harmonic motion imaging (HR-HMI) for tissue biomechanical property characterization.

    PubMed

    Ma, Teng; Qian, Xuejun; Chiu, Chi Tat; Yu, Mingyue; Jung, Hayong; Tung, Yao-Sheng; Shung, K Kirk; Zhou, Qifa

    2015-02-01

    Elastography, capable of mapping the biomechanical properties of biological tissues, serves as a useful technique for clinicians to perform disease diagnosis and determine stages of many diseases. Many acoustic radiation force (ARF) based elastography, including acoustic radiation force impulse (ARFI) imaging and harmonic motion imaging (HMI), have been developed to remotely assess the elastic properties of tissues. However, due to the lower operating frequencies of these approaches, their spatial resolutions are insufficient for revealing stiffness distribution on small scale applications, such as cancerous tumor margin detection, atherosclerotic plaque composition analysis and ophthalmologic tissue characterization. Though recently developed ARF-based optical coherence elastography (OCE) methods open a new window for the high resolution elastography, shallow imaging depths significantly limit their usefulness in clinics. The aim of this study is to develop a high-resolution HMI method to assess the tissue biomechanical properties with acceptable field of view (FOV) using a 4 MHz ring transducer for efficient excitation and a 40 MHz needle transducer for accurate detection. Under precise alignment of two confocal transducers, the high-resolution HMI system has a lateral resolution of 314 µm and an axial resolution of 
147 µm with an effective FOV of 2 mm in depth. The performance of this high resolution imaging system was validated on the agar-based tissue mimicking phantoms with different stiffness distributions. These data demonstrated the imaging system's improved resolution and sensitivity on differentiating materials with varying stiffness. In addition, ex vivo imaging of a human atherosclerosis coronary artery demonstrated the capability of high resolution HMI in identifying layer-specific structures and characterizing atherosclerotic plaques based on their stiffness differences. All together high resolution HMI appears to be a promising ultrasound

  20. High-resolution harmonic motion imaging (HR-HMI) for tissue biomechanical property characterization

    PubMed Central

    Ma, Teng; Qian, Xuejun; Chiu, Chi Tat; Yu, Mingyue; Jung, Hayong; Tung, Yao-Sheng; Shung, K. Kirk

    2015-01-01

    Background Elastography, capable of mapping the biomechanical properties of biological tissues, serves as a useful technique for clinicians to perform disease diagnosis and determine stages of many diseases. Many acoustic radiation force (ARF) based elastography, including acoustic radiation force impulse (ARFI) imaging and harmonic motion imaging (HMI), have been developed to remotely assess the elastic properties of tissues. However, due to the lower operating frequencies of these approaches, their spatial resolutions are insufficient for revealing stiffness distribution on small scale applications, such as cancerous tumor margin detection, atherosclerotic plaque composition analysis and ophthalmologic tissue characterization. Though recently developed ARF-based optical coherence elastography (OCE) methods open a new window for the high resolution elastography, shallow imaging depths significantly limit their usefulness in clinics. Methods The aim of this study is to develop a high-resolution HMI method to assess the tissue biomechanical properties with acceptable field of view (FOV) using a 4 MHz ring transducer for efficient excitation and a 40 MHz needle transducer for accurate detection. Under precise alignment of two confocal transducers, the high-resolution HMI system has a lateral resolution of 314 µm and an axial resolution of 
147 µm with an effective FOV of 2 mm in depth. Results The performance of this high resolution imaging system was validated on the agar-based tissue mimicking phantoms with different stiffness distributions. These data demonstrated the imaging system’s improved resolution and sensitivity on differentiating materials with varying stiffness. In addition, ex vivo imaging of a human atherosclerosis coronary artery demonstrated the capability of high resolution HMI in identifying layer-specific structures and characterizing atherosclerotic plaques based on their stiffness differences. Conclusions All together high resolution HMI

  1. Super-Resolution Reconstruction of High-Resolution Satellite ZY-3 TLC Images

    PubMed Central

    Li, Lin; Wang, Wei; Luo, Heng; Ying, Shen

    2017-01-01

    Super-resolution (SR) image reconstruction is a technique used to recover a high-resolution image using the cumulative information provided by several low-resolution images. With the help of SR techniques, satellite remotely sensed images can be combined to achieve a higher-resolution image, which is especially useful for a two- or three-line camera satellite, e.g., the ZY-3 high-resolution Three Line Camera (TLC) satellite. In this paper, we introduce the application of the SR reconstruction method, including motion estimation and the robust super-resolution technique, to ZY-3 TLC images. The results show that SR reconstruction can significantly improve both the resolution and image quality of ZY-3 TLC images. PMID:28481287

  2. Super-Resolution Reconstruction of High-Resolution Satellite ZY-3 TLC Images.

    PubMed

    Li, Lin; Wang, Wei; Luo, Heng; Ying, Shen

    2017-05-07

    Super-resolution (SR) image reconstruction is a technique used to recover a high-resolution image using the cumulative information provided by several low-resolution images. With the help of SR techniques, satellite remotely sensed images can be combined to achieve a higher-resolution image, which is especially useful for a two- or three-line camera satellite, e.g., the ZY-3 high-resolution Three Line Camera (TLC) satellite. In this paper, we introduce the application of the SR reconstruction method, including motion estimation and the robust super-resolution technique, to ZY-3 TLC images. The results show that SR reconstruction can significantly improve both the resolution and image quality of ZY-3 TLC images.

  3. Content based sub-image retrieval system for high resolution pathology images using salient interest points.

    PubMed

    Mehta, Neville; Alomari, Raja' S; Chaudhary, Vipin

    2009-01-01

    Content-based image retrieval systems for digital pathology require sub-image retrieval rather than the whole image retrieval for the system to be of clinical use. Digital pathology images are huge in size and thus the pathologist is interested in retrieving specific structures from the whole images in the database along with the previous diagnosis of the retrieved sub-image. We propose a content-based sub-image retrieval system (sCBIR) framework for high resolution digital pathology images. We utilize scale-invariant feature extraction and present an efficient and robust searching mechanism for indexing the images as well as for query execution of sub-image retrieval. We present a working sCBIR system and show results of testing our system on a set of queries for specific structures of interest for pathologists in clinical use. The outcomes of the sCBIR system are compared to manual search and there is an 80% match in the top five searches.

  4. Fast access to reduced-resolution subsamples of high-resolution images

    NASA Astrophysics Data System (ADS)

    Isaacson, Joel S.

    1991-08-01

    Frequently, displaying a digital image requires reducing the volume of data contained in a high-resolution image. This reduction can be performed by sub- sampling pixels from the high resolution image. Some examples of systems that need fast access to reduced resolution images are: modern digital prepress production; flight simulators; terrestrial planetary and astronomical imaging systems. On standard workstations, a lower resolution image cannot be read without essentially reading the whole high-resolution image. This paper demonstrates a method that allows fast access to lower scale resolution images. The method has the following characteristics. The proposed storage format greatly lessens the time needed to read a low-resolution image typically by an order of magnitude. The storage format supports efficient reading of multiple scale reduced resolutions. The image file size remains the same as in current formats. No penalty is imposed by using this new format for any operation that uses the image at full resolution. Additionally, an efficient method for rotating images in this format is demonstrated that is many times faster than methods currently employed. The last section gives benchmarks that demonstrate the utility of this format for reading an image at low resolution.

  5. Automatic cloud-free image generation from high-resolution multitemporal imagery

    NASA Astrophysics Data System (ADS)

    Han, Youkyung; Bovolo, Francesca; Lee, Won Hee

    2017-04-01

    The aim of this paper is to document the automatic reconstruction of clouds and their cast shadows for the generation of spontaneous cloud-free images from high-resolution multitemporal images. To apply the proposed technique, a cloud-free reference image, which has the same position as a target image acquired at a different time, is required. First, the cloud region in the target image is detected based on integration of thick and peripheral cloud candidate regions. Next, the detected cloud region is restored using the pixel values of the target image by considering their location relative to the reference images. Finally, the pixel values of the restored image are separately normalized to the values of the reference image to generate a natural-looking cloud-free image. Multitemporal KOMPSAT-2 high-resolution images are used to construct study sites for evaluation of the proposed method in diverse cloud-cover cases. The experimental results show that the proposed method can automatically generate cloud-free images from high-resolution multitemporal images with reasonable qualitative and quantitative performance.

  6. High Resolution Photoelectron Spectroscopy of Au_2^- and Au_4^- by Photoelectron Imaging

    NASA Astrophysics Data System (ADS)

    Leon, Iker; Yang, Zheng; Wang, Lai-Sheng

    2013-06-01

    We report high resolution photoelectron spectra of Au_2^- and Au_4^- obtained with a newly-built photoelectron imaging apparatus. Gold anions are produced by laser vaporization and the desired specie is mass selected and focused into the collinear velocity-map imaging (VMI) lens assembly. The design of the imaging lens has allowed us to obtain less than 0.9% energy resolution for high kinetic energy electrons ( > 1eV) while maintaining wavenumber resolution for low kinetic energy electrons. Although gold dimer and tetramer have been studied in the past, we present spectroscopic results under high resolution. For Au_2^-, we report high resolution spectra with an accurate determination of the electron affinity together with a complete vibrational assignment, for both the anion and neutral ground states, while for Au_4^-, we are able to resolve a low frequency mode and obtain accurately the adiabatic detachment energy.

  7. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    SciTech Connect

    Kotasidis, Fotis A.; Angelis, Georgios I.; Anton-Rodriguez, Jose; Matthews, Julian C.; Reader, Andrew J.; Zaidi, Habib

    2014-05-15

    Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution

  8. A snapshot multispectral imager with integrated tiled filters and optical duplication

    NASA Astrophysics Data System (ADS)

    Geelen, Bert; Tack, Nicolaas; Lambrechts, Andy

    2013-03-01

    Although the potential of spectral imaging has been demonstrated in research environments, its adoption by industry has so far been limited due to the lack of high speed, low cost and compact spectral cameras. We have previously presented work to overcome this limitation by monolithically integrating optical interference filters on top of standard CMOS image sensors for high resolution pushbroom hyperspectral cameras. These cameras require a scanning of the scene and therefore introduce operator complexity due to the need for synchronization and alignment of the scanning to the camera. This typically leads to problems with motion blur, reduced SNR in high speed applications and detection latency and overall restricts the types of applications that can use this system. This paper introduces a novel snapshot multispectral imager concept based on optical filters monolithically integrated on top of a standard CMOS image sensor. By using monolithic integration for the dedicated, high quality spectral filters at its core, it enables the use of mass-produced fore-optics, reducing the total system cost. It overcomes the problems mentioned for scanning applications by snapshot acquisition, where an entire multispectral data cube is sensed at one discrete point in time. This is achieved by applying a novel, tiled filter layout and an optical sub-system which simultaneously duplicates the scene onto each filter tile. Through the use of monolithically integrated optical filters it retains the qualities of compactness, low cost and high acquisition speed, differentiating it from other snapshot spectral cameras based on heterogeneously integrated custom optics. Moreover, thanks to a simple cube assembly process, it enables real-time, low-latency operation. Our prototype camera can acquire multispectral image cubes of 256x256 pixels over 32 bands in the spectral range of 600-1000nm at a speed of about 30 cubes per second at daylight conditions up to 340 cubes per second at higher

  9. Ultra-high resolution of radiocesium distribution detection based on Cherenkov light imaging

    NASA Astrophysics Data System (ADS)

    Yamamoto, Seiichi; Ogata, Yoshimune; Kawachi, Naoki; Suzui, Nobuo; Yin, Yong-Gen; Fujimaki, Shu

    2015-03-01

    After the nuclear disaster in Fukushima, radiocesium contamination became a serious scientific concern and research of its effects on plants increased. In such plant studies, high resolution images of radiocesium are required without contacting the subjects. Cherenkov light imaging of beta radionuclides has inherently high resolution and is promising for plant research. Since 137Cs and 134Cs emit beta particles, Cherenkov light imaging will be useful for the imaging of radiocesium distribution. Consequently, we developed and tested a Cherenkov light imaging system. We used a high sensitivity cooled charge coupled device (CCD) camera (Hamamatsu Photonics, ORCA2-ER) for imaging Cherenkov light from 137Cs. A bright lens (Xenon, F-number: 0.95, lens diameter: 25 mm) was mounted on the camera and placed in a black box. With a 100-μm 137Cs point source, we obtained 220-μm spatial resolution in the Cherenkov light image. With a 1-mm diameter, 320-kBq 137Cs point source, the source was distinguished within 2-s. We successfully obtained Cherenkov light images of a plant whose root was dipped in a 137Cs solution, radiocesium-containing samples as well as line and character phantom images with our imaging system. Cherenkov light imaging is promising for the high resolution imaging of radiocesium distribution without contacting the subject.

  10. High-resolution myocardial perfusion mapping in small animals in vivo by spin-labeling gradient-echo imaging.

    PubMed

    Kober, Frank; Iltis, Isabelle; Izquierdo, Marguerite; Desrois, Martine; Ibarrola, Danielle; Cozzone, Patrick J; Bernard, Monique

    2004-01-01

    An ECG and respiration-gated spin-labeling gradient-echo imaging technique is proposed for the quantitative and completely noninvasive measurement and mapping of myocardial perfusion in small animals in vivo. In contrast to snapshot FLASH imaging, the spatial resolution of the perfusion maps is not limited by the heart rate. A significant improvement in image quality is achieved by synchronizing the inversion pulse to the respiration movements of the animals, thereby allowing for spontaneous respiration. High-resolution myocardial perfusion maps (in-plane resolution=234 x 468 microm2) demonstrating the quality of the perfusion measurement were obtained at 4.7 T in a group of seven freely breathing Wistar-Kyoto rats under isoflurane anesthesia. The mean perfusion value (group average +/- SD) was 5.5 +/- 0.7 ml g(-1)min(-1). In four animals, myocardial perfusion was mapped and measured under cardiac dobutamine stress. Perfusion increased to 11.1 +/- 1.9 ml g(-1)min(-1). The proposed method is particularly useful for the study of small rodents at high fields.

  11. Toward an image compression algorithm for the high-resolution electronic still camera

    NASA Technical Reports Server (NTRS)

    Nerheim, Rosalee

    1989-01-01

    Taking pictures with a camera that uses a digital recording medium instead of film has the advantage of recording and transmitting images without the use of a darkroom or a courier. However, high-resolution images contain an enormous amount of information and strain data-storage systems. Image compression will allow multiple images to be stored in the High-Resolution Electronic Still Camera. The camera is under development at Johnson Space Center. Fidelity of the reproduced image and compression speed are of tantamount importance. Lossless compression algorithms are fast and faithfully reproduce the image, but their compression ratios will be unacceptably low due to noise in the front end of the camera. Future efforts will include exploring methods that will reduce the noise in the image and increase the compression ratio.

  12. High-Resolution Imaging of Dendrimers Used in Drug Delivery via Scanning Probe Microscopy.

    PubMed

    Shi, Lifang; Fleming, Christopher J; Riechers, Shawn L; Yin, Nai-Ning; Luo, Juntao; Lam, Kit S; Liu, Gang-Yu

    2011-01-01

    Dendrimers and telodendrimer micelles represent two new classes of vehicles for drug delivery that have attracted much attention recently. Their structural characterization at the molecular and submolecular level remains a challenge due to the difficulties in reaching high resolution when imaging small particles in their native media. This investigation offers a new approach towards this challenge, using scanning tunneling microscopy (STM) and atomic force microscopy (AFM). By using new sample preparation protocols, this work demonstrates that (a) intramolecular features such as drug molecules and dendrimer termini can be resolved; and (b) telodendrimer micelles can be immobilized on the surface without compromising structural integrity, and as such, high resolution AFM imaging may be performed to attain 3D information. This high-resolution structural information should enhance our knowledge of the nanocarrier structure and nanocarrier-drug interaction and, therefore, facilitate design and optimization of the efficiency in drug delivery.

  13. Utility of high-resolution MR imaging in demonstrating transmural pathologic changes in Crohn disease.

    PubMed

    Sinha, Rakesh; Rajiah, Prabhakar; Murphy, Paul; Hawker, Peter; Sanders, Scott

    2009-10-01

    Magnetic resonance (MR) imaging has emerged as an imaging modality that can be used to help diagnose and evaluate Crohn disease of the small and large bowel. MR imaging has high diagnostic accuracy in the detection of Crohn disease, and high-resolution thin-section MR images can demonstrate transmural pathologic changes of Crohn disease from the level of the mucosa to that of the mesentery. High-resolution MR image data also may be used to construct high-quality multiplanar and endoluminal views that may provide additional diagnostic information. Knowledge of the MR imaging findings of Crohn disease and how they correlate with the pathologic features of the disease is important to facilitate accurate diagnosis and detect complications.

  14. Magellan radar image compared to high resolution Earth-based image of Venus

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A strip of a Magellan radar image (left) is compared to a high resolution Earth-based radar image of Venus, obtained by the U.S. National Astronomy and Ionosphere Center's Arecibo Observatory in Puerto Rico. The small white box in the Arecibo image corresponds to the Magellan image. This portion of the Magellan imagery shows a small region on the east flank of a major volcanic upland called Beta Regio. The image is centered at 23 degrees north latitude and 286.7 degrees east longitude. The ridge and valley network in the middle part of the image is formed by intersecting faults which have broken the Venusian crust into a complex deformed type of surface called tessera, the Latin word for tile. The parallel mountains and valleys resemble the Basin and Range Province in the western United States. The irregular dark patch near the top of the image is a smooth surface, probably formed, according to scientists, by lava flows in a region about 10 kilometers (6 miles) across. Similar dark sur

  15. High-resolution bone imaging for osteoporosis diagnostics and therapy monitoring using clinical MDCT and MRI.

    PubMed

    Baum, T; Karampinos, D C; Liebl, H; Rummeny, E J; Waldt, S; Bauer, J S

    2013-01-01

    Osteoporosis is classified as a public health problem due to its increased risk for fragility fractures. Osteoporotic fractures, in particular spine and hip fractures, are associated with a high morbidity and mortality, and generate immense financial cost. The World Health Organisation (WHO) based the diagnosis of osteoporosis on the measurement of bone mineral density (BMD) using dual-energy X-ray absorptiometry (DXA). However, BMD values of subjects with versus without osteoporotic fractures overlap. Furthermore, it was reported that the anti-fracture effects of drugs could be only partially explained by their effects on BMD. Bone strength reflects the integration of BMD and bone quality. The later can be partly determined by measurements of bone microstructure. Therefore, substantial research efforts have been undertaken to assess bone microstructure by using high-resolution imaging techniques, including high-resolution peripheral quantitative computed tomography (hr-pQCT), high-resolution multi-detector computed tomography (MDCT), and high-resolution magnetic resonance imaging (MRI). Clinical MDCT and MRI systems are broadly available and allow an adequate depiction of the bone microstructure at the clinically most important fracture sites, i.e. radius, spine and hip. Bone microstructure parameters and finite element models can be computed in high-resolution MDCT and MR images. These measurements improved the prediction of bone strength beyond the DXA-derived BMD and revealed pharmacotherapy effects, which are partly not captured by BMD. Therefore, high-resolution bone imaging using clinical MDCT and MRI may be beneficial for osteoporosis diagnostics and allow a highly sensitive monitoring of drug treatment, which plays an important role in the prevention of fragility fractures.

  16. The Potential for Bayesian Compressive Sensing to Significantly Reduce Electron Dose in High Resolution STEM Images

    SciTech Connect

    Stevens, Andrew J.; Yang, Hao; Carin, Lawrence; Arslan, Ilke; Browning, Nigel D.

    2014-02-11

    The use of high resolution imaging methods in the scanning transmission electron microscope (STEM) is limited in many cases by the sensitivity of the sample to the beam and the onset of electron beam damage (for example in the study of organic systems, in tomography and during in-situ experiments). To demonstrate that alternative strategies for image acquisition can help alleviate this beam damage issue, here we apply compressive sensing via Bayesian dictionary learning to high resolution STEM images. These experiments successively reduce the number of pixels in the image (thereby reducing the overall dose while maintaining the high resolution information) and show promising results for reconstructing images from this reduced set of randomly collected measurements. We show that this approach is valid for both atomic resolution images and nanometer resolution studies, such as those that might be used in tomography datasets, by applying the method to images of strontium titanate and zeolites. As STEM images are acquired pixel by pixel while the beam is scanned over the surface of the sample, these post acquisition manipulations of the images can, in principle, be directly implemented as a low-dose acquisition method with no change in the electron optics or alignment of the microscope itself.

  17. Wide-aperture aspherical lens for high-resolution terahertz imaging

    NASA Astrophysics Data System (ADS)

    Chernomyrdin, Nikita V.; Frolov, Maxim E.; Lebedev, Sergey P.; Reshetov, Igor V.; Spektor, Igor E.; Tolstoguzov, Viktor L.; Karasik, Valeriy E.; Khorokhorov, Alexei M.; Koshelev, Kirill I.; Schadko, Aleksander O.; Yurchenko, Stanislav O.; Zaytsev, Kirill I.

    2017-01-01

    In this paper, we introduce wide-aperture aspherical lens for high-resolution terahertz (THz) imaging. The lens has been designed and analyzed by numerical methods of geometrical optics and electrodynamics. It has been made of high-density polyethylene by shaping at computer-controlled lathe and characterized using a continuous-wave THz imaging setup based on a backward-wave oscillator and Golay detector. The concept of image contrast has been implemented to estimate image quality. According to the experimental data, the lens allows resolving two points spaced at 0.95λ distance with a contrast of 15%. To highlight high resolution in the THz images, the wide-aperture lens has been employed for studying printed electronic circuit board containing sub-wavelength-scale elements. The observed results justify the high efficiency of the proposed lens design.

  18. Wide-aperture aspherical lens for high-resolution terahertz imaging.

    PubMed

    Chernomyrdin, Nikita V; Frolov, Maxim E; Lebedev, Sergey P; Reshetov, Igor V; Spektor, Igor E; Tolstoguzov, Viktor L; Karasik, Valeriy E; Khorokhorov, Alexei M; Koshelev, Kirill I; Schadko, Aleksander O; Yurchenko, Stanislav O; Zaytsev, Kirill I

    2017-01-01

    In this paper, we introduce wide-aperture aspherical lens for high-resolution terahertz (THz) imaging. The lens has been designed and analyzed by numerical methods of geometrical optics and electrodynamics. It has been made of high-density polyethylene by shaping at computer-controlled lathe and characterized using a continuous-wave THz imaging setup based on a backward-wave oscillator and Golay detector. The concept of image contrast has been implemented to estimate image quality. According to the experimental data, the lens allows resolving two points spaced at 0.95λ distance with a contrast of 15%. To highlight high resolution in the THz images, the wide-aperture lens has been employed for studying printed electronic circuit board containing sub-wavelength-scale elements. The observed results justify the high efficiency of the proposed lens design.

  19. High Resolution Bathymetry Estimation Improvement with Single Image Super-Resolution Algorithm Super-Resolution Forests

    DTIC Science & Technology

    2017-01-26

    bathymetry data. Borrowing the machine -learning technique of “training and testing” on a dictionary of sets data, we could create high resolution estimates...interpolation. 26-01-2017 Memorandum Report Bathymetry Super-Resolution Machine learning Single image Estimation Naval Research Laboratory, Code 5514

  20. Automatic Detection of Sub-Kilometer Craters in High Resolution Images of Mars

    NASA Astrophysics Data System (ADS)

    Urbach, E. R.; Stepinski, T. F.

    2008-03-01

    A method for automatic detection of impact craters in high resolution images of Mars is presented. This new method enables detection of sub-kilometer craters that are too small to be cataloged by previous methods and too numerous for manual detection.

  1. A compact high-resolution 3-D imaging spectrometer for discovering Oases on Mars

    USGS Publications Warehouse

    Ge, J.; Ren, D.; Lunine, J.I.; Brown, R.H.; Yelle, R.V.; Soderblom, L.A.; ,

    2002-01-01

    A new design for a very lightweight, very high throughput reflectance sectrometer enabled by two new technologies being developed is presented. These new technologies include integral field unit optics to enable simultaneous imaging and spectroscopy at high spatial resolution with an infrared (IR) array, and silicon grisms to enable compact and high-resolution spectroscopy.

  2. A high resolution magneto-optical system for imaging of individual magnetic flux quanta.

    PubMed

    Golubchik, Daniel; Polturak, Emil; Koren, Gad; Lipson, Stephen G

    2009-08-31

    A high-resolution magneto-optical imaging system is described. In this system magneto-optical Kerr effect is utilized for resolving individual flux quanta in a type II superconductor. Using an ultra thin EuSe indicator a spatial resolution of 0.8 microm is achieved.

  3. Multiscale snapshot imaging spectrometer with large FOV and fast speed

    NASA Astrophysics Data System (ADS)

    Ji, Yiqun; Sasian, Jose; Chen, Yuheng; Zhou, Jiankang

    2014-11-01

    A novel snapshot imaging spectrometer with large field-of-view (FOV) up to 100° is achieved by taking the advantages of a multiscale fore-optics and a compact Offner imaging spectrograph. Based on the diffraction imaging theory, the multiscale fore-optics composed of a monocentric spherical lens and multi-channel microlens array is designed, over which panchromatic images with small FOV are of uniform image quality. And identical imaging spectrographs with a dimension less than 30 cubic millimeters and with a high spectral resolution of about 2nm are designed correspondingly. The presented imaging spectrometer works at the visible wavelength range which is from 400nm to 780nm. It is of a fast speed about F/2.4 and a compact configuration of only 200mm×300mm×300mm in dimension. But the smile and keystone distortions are negligible.

  4. Research On The Classification Of High Resolution Image Based On Object-oriented And Class Rule

    NASA Astrophysics Data System (ADS)

    Li, C. K.; Fang, W.; Dong, X. J.

    2015-06-01

    With the development of remote sensing technology, the spatial resolution, spectral resolution and time resolution of remote sensing data is greatly improved. How to efficiently process and interpret the massive high resolution remote sensing image data for ground objects, which with spatial geometry and texture information, has become the focus and difficulty in the field of remote sensing research. An object oriented and rule of the classification method of remote sensing data has presents in this paper. Through the discovery and mining the rich knowledge of spectrum and spatial characteristics of high-resolution remote sensing image, establish a multi-level network image object segmentation and classification structure of remote sensing image to achieve accurate and fast ground targets classification and accuracy assessment. Based on worldview-2 image data in the Zangnan area as a study object, using the object-oriented image classification method and rules to verify the experiment which is combination of the mean variance method, the maximum area method and the accuracy comparison to analysis, selected three kinds of optimal segmentation scale and established a multi-level image object network hierarchy for image classification experiments. The results show that the objectoriented rules classification method to classify the high resolution images, enabling the high resolution image classification results similar to the visual interpretation of the results and has higher classification accuracy. The overall accuracy and Kappa coefficient of the object-oriented rules classification method were 97.38%, 0.9673; compared with object-oriented SVM method, respectively higher than 6.23%, 0.078; compared with object-oriented KNN method, respectively more than 7.96%, 0.0996. The extraction precision and user accuracy of the building compared with object-oriented SVM method, respectively higher than 18.39%, 3.98%, respectively better than the object-oriented KNN method 21

  5. High resolution retinal image restoration with wavefront sensing and self-extracted filtering

    NASA Astrophysics Data System (ADS)

    Yang, Shuyu; Erry, Gavin; Nemeth, Sheila; Mitra, Sunanda; Soliz, Peter

    2005-04-01

    Diagnosis and treatment of retinal diseases such as diabetic retinopathy commonly rely on a clear view of the retina. The challenge in obtaining high quality retinal image lies in the design of the imaging system that can reduce the strong aberrations of the human eye. Since the amplitudes of human eye aberrations decrease rapidly as the aberration order goes up, it is more cost-effective to correct low order aberrations with adaptive optical devices while process high order aberrations through image processing. A cost effective fundus imaging device that can capture high quality retinal images with 2-5 times higher resolution than conventional retinal images has been designed [1]. This imager improves image quality by attaching complementary adaptive optical components to a conventional fundus camera. However, images obtained with the high resolution camera are still blurred due to some uncorrected aberrations as well as defocusing resulting from non-isoplanatic effect. Therefore, advanced image restoration algorithms have been employed for further improvement in image quality. In this paper, we use wavefront-based and self-extracted blind deconvolution techniques to restore images captured by the high resolution fundus camera. We demonstrate that through such techniques, pathologies that are critical to retinal disease diagnosis but not clear or not observable in the original image can be observed clearly in the restored images. Image quality evaluation is also used to finalize the development of a cost-effective, fast, and automated diagnostic system that can be used clinically.

  6. A methodology for high resolution digital image correlation in high temperature experiments

    NASA Astrophysics Data System (ADS)

    Blaber, Justin; Adair, Benjamin S.; Antoniou, Antonia

    2015-03-01

    We propose a methodology for performing high resolution Digital Image Correlation (DIC) analysis during high-temperature mechanical tests. Specifically, we describe a technique for producing a stable, high-quality pattern on metal surfaces along with a simple optical system that uses a visible-range camera and a long-range microscope. The results are analyzed with a high-quality open-source DIC software developed by us. Using the proposed technique, we successfully acquired high-resolution strain maps of the crack tip field in a nickel superalloy sample at 1000 °C.

  7. Development of a Miniature Snapshot Multispectral Imager

    DTIC Science & Technology

    2010-09-01

    Martins, J. S.; Wolffenbuttel, R. F.; Correia, J. H. An Array of Fabry – Perot Optical – Channels for Biological Fluids Analysis. Sensors and...applications. The system is low weight and portable with a miniature platform, and requires low power. The imager uses a 4×4 Fabry - Perot filter array...shadow mask technique to fabricate a Fabry - Perot etalon with multilayer dielectric mirrors. The filter array subsystem is installed in a commercial

  8. Quantitative analysis of high-resolution microendoscopic images for diagnosis of esophageal squamous cell carcinoma.

    PubMed

    Shin, Dongsuk; Protano, Marion-Anna; Polydorides, Alexandros D; Dawsey, Sanford M; Pierce, Mark C; Kim, Michelle Kang; Schwarz, Richard A; Quang, Timothy; Parikh, Neil; Bhutani, Manoop S; Zhang, Fan; Wang, Guiqi; Xue, Liyan; Wang, Xueshan; Xu, Hong; Anandasabapathy, Sharmila; Richards-Kortum, Rebecca R

    2015-02-01

    High-resolution microendoscopy is an optical imaging technique with the potential to improve the accuracy of endoscopic screening for esophageal squamous neoplasia. Although these microscopic images can be interpreted readily by trained personnel, quantitative image analysis software could facilitate the use of this technology in low-resource settings. In this study, we developed and evaluated quantitative image analysis criteria for the evaluation of neoplastic and non-neoplastic squamous esophageal mucosa. We performed an image analysis of 177 patients undergoing standard upper endoscopy for screening or surveillance of esophageal squamous neoplasia, using high-resolution microendoscopy, at 2 hospitals in China and at 1 hospital in the United States from May 2010 to October 2012. Biopsy specimens were collected from imaged sites (n = 375), and a consensus diagnosis was provided by 2 expert gastrointestinal pathologists and used as the standard. Quantitative information from the high-resolution images was used to develop an algorithm to identify high-grade squamous dysplasia or invasive squamous cell cancer, based on histopathology findings. Optimal performance was obtained using the mean nuclear area as the basis for classification, resulting in sensitivities and specificities of 93% and 92% in the training set, 87% and 97% in the test set, and 84% and 95% in an independent validation set, respectively. High-resolution microendoscopy with quantitative image analysis can aid in the identification of esophageal squamous neoplasia. Use of software-based image guides may overcome issues of training and expertise in low-resource settings, allowing for widespread use of these optical biopsy technologies. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. Quantitative Analysis of High-Resolution Microendoscopic Images for Diagnosis of Esophageal Squamous Cell Carcinoma

    PubMed Central

    Shin, Dongsuk; Protano, Marion-Anna; Polydorides, Alexandros D.; Dawsey, Sanford M.; Pierce, Mark C.; Kim, Michelle Kang; Schwarz, Richard A.; Quang, Timothy; Parikh, Neil; Bhutani, Manoop S.; Zhang, Fan; Wang, Guiqi; Xue, Liyan; Wang, Xueshan; Xu, Hong; Anandasabapathy, Sharmila; Richards-Kortum, Rebecca R.

    2014-01-01

    Background & Aims High-resolution microendoscopy is an optical imaging technique with the potential to improve the accuracy of endoscopic screening for esophageal squamous neoplasia. Although these microscopic images can readily be interpreted by trained personnel, quantitative image analysis software could facilitate the use of this technology in low-resource settings. In this study we developed and evaluated quantitative image analysis criteria for the evaluation of neoplastic and non-neoplastic squamous esophageal mucosa. Methods We performed image analysis of 177 patients undergoing standard upper endoscopy for screening or surveillance of esophageal squamous neoplasia, using high-resolution microendoscopy, at 2 hospitals in China and 1 in the United States from May 2010 to October 2012. Biopsies were collected from imaged sites (n=375); a consensus diagnosis was provided by 2 expert gastrointestinal pathologists and used as the standard. Results Quantitative information from the high-resolution images was used to develop an algorithm to identify high-grade squamous dysplasia or invasive squamous cell cancer, based on histopathology findings. Optimal performance was obtained using mean nuclear area as the basis for classification, resulting in sensitivities and specificities of 93% and 92% in the training set, 87% and 97% in the test set, and 84% and 95% in an independent validation set, respectively. Conclusions High-resolution microendoscopy with quantitative image analysis can aid in the identification of esophageal squamous neoplasia. Use of software-based image guides may overcome issues of training and expertise in low-resource settings, allowing for widespread use of these optical biopsy technologies. PMID:25066838

  10. Direct high-resolution label-free imaging of cellular nanostructure dynamics in living cells

    NASA Astrophysics Data System (ADS)

    Heo, Chaejeong; Lee, Sohee; Lee, Si Young; Jeong, Mun Seok; Lee, Young Hee; Suh, Minah

    2013-06-01

    We report the application of an optical microscope equipped with a high-resolution dark-field condenser for detecting dynamic responses of cellular nanostructures in real time. Our system provides an easy-to-use technique to visualize biological specimens without any staining. This system can visualize the dynamic behavior of nanospheres and nanofibers, such as F-actin, at the leading edges of adjacent neuronal cells. We confirmed that the nanofibers imaged with this high-resolution optical microscopic technique are F-actin by using fluorescence microscopy after immunostaining the F-actin of fixed cells. Furthermore, cellular dynamics are enhanced by applying noncontact electric field stimulation through a transparent graphene electric field stimulator. High-resolution label-free optical microscopy enables the visualization of nanofiber dynamics initiated by filopodial nanofiber contacts. In conclusion, our optical microscopy system allows the visualization of nanoscale cellular dynamics under various external stimuli in real time without specific staining.

  11. Object Manifold Alignment for Multi-Temporal High Resolution Remote Sensing Images Classification

    NASA Astrophysics Data System (ADS)

    Gao, G.; Zhang, M.; Gu, Y.

    2017-05-01

    Multi-temporal remote sensing images classification is very useful for monitoring the land cover changes. Traditional approaches in this field mainly face to limited labelled samples and spectral drift of image information. With spatial resolution improvement, "pepper and salt" appears and classification results will be effected when the pixelwise classification algorithms are applied to high-resolution satellite images, in which the spatial relationship among the pixels is ignored. For classifying the multi-temporal high resolution images with limited labelled samples, spectral drift and "pepper and salt" problem, an object-based manifold alignment method is proposed. Firstly, multi-temporal multispectral images are cut to superpixels by simple linear iterative clustering (SLIC) respectively. Secondly, some features obtained from superpixels are formed as vector. Thirdly, a majority voting manifold alignment method aiming at solving high resolution problem is proposed and mapping the vector data to alignment space. At last, all the data in the alignment space are classified by using KNN method. Multi-temporal images from different areas or the same area are both considered in this paper. In the experiments, 2 groups of multi-temporal HR images collected by China GF1 and GF2 satellites are used for performance evaluation. Experimental results indicate that the proposed method not only has significantly outperforms than traditional domain adaptation methods in classification accuracy, but also effectively overcome the problem of "pepper and salt".

  12. High resolution quantitative phase imaging of live cells with constrained optimization approach

    NASA Astrophysics Data System (ADS)

    Pandiyan, Vimal Prabhu; Khare, Kedar; John, Renu

    2016-03-01

    Quantitative phase imaging (QPI) aims at studying weakly scattering and absorbing biological specimens with subwavelength accuracy without any external staining mechanisms. Use of a reference beam at an angle is one of the necessary criteria for recording of high resolution holograms in most of the interferometric methods used for quantitative phase imaging. The spatial separation of the dc and twin images is decided by the reference beam angle and Fourier-filtered reconstructed image will have a very poor resolution if hologram is recorded below a minimum reference angle condition. However, it is always inconvenient to have a large reference beam angle while performing high resolution microscopy of live cells and biological specimens with nanometric features. In this paper, we treat reconstruction of digital holographic microscopy images as a constrained optimization problem with smoothness constraint in order to recover only complex object field in hologram plane even with overlapping dc and twin image terms. We solve this optimization problem by gradient descent approach iteratively and the smoothness constraint is implemented by spatial averaging with appropriate size. This approach will give excellent high resolution image recovery compared to Fourier filtering while keeping a very small reference angle. We demonstrate this approach on digital holographic microscopy of live cells by recovering the quantitative phase of live cells from a hologram recorded with nearly zero reference angle.

  13. Multi-Scale Segmentation of High Resolution Remote Sensing Images by Integrating Multiple Features

    NASA Astrophysics Data System (ADS)

    Di, Y.; Jiang, G.; Yan, L.; Liu, H.; Zheng, S.

    2017-05-01

    Most of multi-scale segmentation algorithms are not aiming at high resolution remote sensing images and have difficulty to communicate and use layers' information. In view of them, we proposes a method of multi-scale segmentation of high resolution remote sensing images by integrating multiple features. First, Canny operator is used to extract edge information, and then band weighted distance function is built to obtain the edge weight. According to the criterion, the initial segmentation objects of color images can be gained by Kruskal minimum spanning tree algorithm. Finally segmentation images are got by the adaptive rule of Mumford-Shah region merging combination with spectral and texture information. The proposed method is evaluated precisely using analog images and ZY-3 satellite images through quantitative and qualitative analysis. The experimental results show that the multi-scale segmentation of high resolution remote sensing images by integrating multiple features outperformed the software eCognition fractal network evolution algorithm (highest-resolution network evolution that FNEA) on the accuracy and slightly inferior to FNEA on the efficiency.

  14. High resolution remote sensing image segmentation based on graph theory and fractal net evolution approach

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Li, H. T.; Han, Y. S.; Gu, H. Y.

    2015-06-01

    Image segmentation is the foundation of further object-oriented image analysis, understanding and recognition. It is one of the key technologies in high resolution remote sensing applications. In this paper, a new fast image segmentation algorithm for high resolution remote sensing imagery is proposed, which is based on graph theory and fractal net evolution approach (FNEA). Firstly, an image is modelled as a weighted undirected graph, where nodes correspond to pixels, and edges connect adjacent pixels. An initial object layer can be obtained efficiently from graph-based segmentation, which runs in time nearly linear in the number of image pixels. Then FNEA starts with the initial object layer and a pairwise merge of its neighbour object with the aim to minimize the resulting summed heterogeneity. Furthermore, according to the character of different features in high resolution remote sensing image, three different merging criterions for image objects based on spectral and spatial information are adopted. Finally, compared with the commercial remote sensing software eCognition, the experimental results demonstrate that the efficiency of the algorithm has significantly improved, and the result can maintain good feature boundaries.

  15. Automatic optimization high-speed high-resolution OCT retinal imaging at 1μm

    NASA Astrophysics Data System (ADS)

    Cua, Michelle; Liu, Xiyun; Miao, Dongkai; Lee, Sujin; Lee, Sieun; Bonora, Stefano; Zawadzki, Robert J.; Mackenzie, Paul J.; Jian, Yifan; Sarunic, Marinko V.

    2015-03-01

    High-resolution OCT retinal imaging is important in providing visualization of various retinal structures to aid researchers in better understanding the pathogenesis of vision-robbing diseases. However, conventional optical coherence tomography (OCT) systems have a trade-off between lateral resolution and depth-of-focus. In this report, we present the development of a focus-stacking optical coherence tomography (OCT) system with automatic optimization for high-resolution, extended-focal-range clinical retinal imaging. A variable-focus liquid lens was added to correct for de-focus in real-time. A GPU-accelerated segmentation and optimization was used to provide real-time layer-specific enface visualization as well as depth-specific focus adjustment. After optimization, multiple volumes focused at different depths were acquired, registered, and stitched together to yield a single, high-resolution focus-stacked dataset. Using this system, we show high-resolution images of the ONH, from which we extracted clinically-relevant parameters such as the nerve fiber layer thickness and lamina cribrosa microarchitecture.

  16. Gas scintillation glass GEM detector for high-resolution X-ray imaging and CT

    NASA Astrophysics Data System (ADS)

    Fujiwara, T.; Mitsuya, Y.; Fushie, T.; Murata, K.; Kawamura, A.; Koishikawa, A.; Toyokawa, H.; Takahashi, H.

    2017-04-01

    A high-spatial-resolution X-ray-imaging gaseous detector has been developed with a single high-gas-gain glass gas electron multiplier (G-GEM), scintillation gas, and optical camera. High-resolution X-ray imaging of soft elements is performed with a spatial resolution of 281 μm rms and an effective area of 100×100 mm. In addition, high-resolution X-ray 3D computed tomography (CT) is successfully demonstrated with the gaseous detector. It shows high sensitivity to low-energy X-rays, which results in high-contrast radiographs of objects containing elements with low atomic numbers. In addition, the high yield of scintillation light enables fast X-ray imaging, which is an advantage for constructing CT images with low-energy X-rays.

  17. High Resolution Electromechanical Imaging of Ferroelectric Materials in a Liquid Environment by Piezoresponse Force Microscopy

    SciTech Connect

    Rodriguez, Brian J; Jesse, Stephen; Baddorf, Arthur P; Kalinin, Sergei V

    2006-01-01

    High-resolution imaging of ferroelectric materials using piezoresponse force microscopy (PFM) is demonstrated in an aqueous environment. The elimination of both long-range electrostatic forces and capillary interactions results in a localization of the ac field to the tip-surface junction and allows the tip-surface contact area to be controlled. This approach results in spatial resolutions approaching the limit of the intrinsic domain-wall width. Imaging at frequencies corresponding to high-order cantilever resonances minimizes the viscous damping and added mass effects on cantilever dynamics and allows sensitivities comparable to ambient conditions. PFM in liquids will provide novel opportunities for high-resolution studies of ferroelectric materials, imaging of soft polymer materials, and imaging of biological systems in physiological environments on, ultimately, the molecular level.

  18. Buildings in High Resolution SAR Images - Identification Based on Citygml Data

    NASA Astrophysics Data System (ADS)

    Auer, S.; Donaubauer, A.

    2015-03-01

    Motivated by the distinct appearance of facades in high resolution SAR images with respect to signal incidence angles and polarizations, this paper introduces a way to fuse SAR imagery and 3D GIS (geoinformation system) data (format: CityGML) based on SAR simulation methods. To this end, the known building geometry is used to simulate the extent of building layover for identifying the related image parts in high resolution TerraSAR-X images. The simulated SAR images are generated and geocoded by an automated processing chain which is initialized by the automated parsing of the CityGML dataset and the TerraSAR-X orbit file. Confirming the functionality of the developed interface between simulation and CityGML, first results are presented for an urban scene in the Munich city center in order to discuss future opportunities in the context of change detection applications.

  19. High-resolution thermal imaging methodology for non-destructive evaluation of historic structures

    NASA Astrophysics Data System (ADS)

    Hess, Michael; Vanoni, David; Petrovic, Vid; Kuester, Falko

    2015-11-01

    This paper presents a methodology for automated, portable thermography, for the acquisition of high-resolution thermal image mosaics supporting the non-destructive evaluation of historic structures. The presented approach increases the spatial resolution of thermal surveys to a level of detail needed for building scale analysis. The integration of a robotic camera platform enables automated alignment of multiple images into a high-resolution thermal image mosaic giving a holistic view of the structure while maintaining a level of detail equaling or exceeding that of traditional spot surveys using existing cameras. Providing a digital workflow for automated data and metadata recording increases the consistency and accuracy of surveys regardless of the location or operator. An imaging workflow and instrumentation are shown for a case-study on buildings in Florence, Italy demonstrating the effectiveness of this methodology for structural diagnostics.

  20. High resolution MRI imaging at 1. 5T using surface coils

    SciTech Connect

    Blinder, R.A.; Herfkens, R.J.; Coleman, R.E.; Johnson, G.A.; Schenck, J.F.; Hart, H.R. Jr.; Foster, T.H.; Edelstein, W.A.

    1985-05-01

    The potential utility of high resolution MRI imaging in various pathologic conditions was explored. As the voxel size of MRI images is decreased the signal per pixel diminishes due to the geometric decrease in volume. In very high resolution images the signal can be small enough to be obscured by Johnson noise. High magnetic field strength (1.5T) coupled with surface coil imaging increases the signal to noise ratio. The surface coils used were single turn coils with diameters of 6 or 11 cm depending on the body part being imaged. A ''clam shell'' crossed coil was used for imaging the knees. Using a 1.5T prototype MRI imaging system we have obtained images with 14.5 cm field of view that are 256 by 256 pixels with a slice thickness of 3 mm. Good signal to noise is obtained using 2DTF imaging with only 2 excitations per phase encoding step (1 average). Images obtained of peripheral joints demonstrate articular cartilage, ligamentous structures, and trabeculae in medullary bone. These exams have demonstrated the changes of rheumatoid arthritis, and the extent of neoplastic involvement in bone. Images of the temporomandibular joint and the neck have been obtained. Parathyroid adenomas have been identified. Surface coil imaging and high magnetic fields allow for high resolution MRI imaging of various anatomic structures. Good signal to noise can be accomplished without extensive signal averaging so that reasonable imaging times and throughput can be realized with voxel dimensions of 0.6 x 0.6 x 3mm.

  1. [Diagnostic efficiency on digital snapshots of the standard radiology imaging].

    PubMed

    Campanella, Nando; Antico, Ettore; Dini, Leonardo; Morosini, Pierpaolo

    2004-12-01

    The authors had experienced the telediagnosis on digital snapshots of standard radiology imaging (chest, abdomen, and bones), sent by e-mailing, to support the medical doctors working in remote areas of developing countries. In order to validate the overall procedure, the authors have set up a simulating model and estimated some parameters of accuracy of the diagnosis on digital snapshots against the golden standard of the diagnosis by direct look. The study concerned the standard X-ray tests of one hundred randomly-selected patients out of a hospital archive. Four years later the diagnosis by direct look, the team of radiologists carried out the blind cross check on the digital snapshots of the radiograms and stated their second diagnosis. Sensibility, specificity, predictive value of positives, predictive value of negatives and efficiency of the whole series have been 83.0, 95.1, 96.1, 79.6 and 88.0%. By breaking up the series by apparatus, the skeleton test shows similar data of the whole series. The chest test shows a specificity and predictive value of positives of 100.0%. Although the number of cases is low, the abdomen test apparently shows a sensibility and predictive value of negatives as high as 100%, but a lower specificity and predictive value of negatives (85.7 and 87.5%). Though this data is supportive to the validation of the procedure, even better results are supposedly achieved by increasing the quality of the snapshots and by improving the skills of using the software.

  2. High Resolution Velocity Map Imaging Photoelectron Spectroscopy of the Beryllium Oxide Anion, BeO-

    NASA Astrophysics Data System (ADS)

    Dermer, Amanda Reed; Mascaritolo, Kyle; Heaven, Michael

    2016-06-01

    The photodetachment spectrum of BeO- has been studied using high resolution velocity map imaging photoelectron spectroscopy. The vibrational contours were imaged and compared with Franck-Condon simulations for the ground and excited states of the neutral. The electron affinity of BeO was measured for the first time, and anisotropies of several transitions were determined. Experimental findings are compared to high level ab initio calculations.

  3. Computational Burden Resulting from Image Recognition of High Resolution Radar Sensors

    PubMed Central

    López-Rodríguez, Patricia; Fernández-Recio, Raúl; Bravo, Ignacio; Gardel, Alfredo; Lázaro, José L.; Rufo, Elena

    2013-01-01

    This paper presents a methodology for high resolution radar image generation and automatic target recognition emphasizing the computational cost involved in the process. In order to obtain focused inverse synthetic aperture radar (ISAR) images certain signal processing algorithms must be applied to the information sensed by the radar. From actual data collected by radar the stages and algorithms needed to obtain ISAR images are revised, including high resolution range profile generation, motion compensation and ISAR formation. Target recognition is achieved by comparing the generated set of actual ISAR images with a database of ISAR images generated by electromagnetic software. High resolution radar image generation and target recognition processes are burdensome and time consuming, so to determine the most suitable implementation platform the analysis of the computational complexity is of great interest. To this end and since target identification must be completed in real time, computational burden of both processes the generation and comparison with a database is explained separately. Conclusions are drawn about implementation platforms and calculation efficiency in order to reduce time consumption in a possible future implementation. PMID:23609804

  4. Computational burden resulting from image recognition of high resolution radar sensors.

    PubMed

    López-Rodríguez, Patricia; Fernández-Recio, Raúl; Bravo, Ignacio; Gardel, Alfredo; Lázaro, José L; Rufo, Elena

    2013-04-22

    This paper presents a methodology for high resolution radar image generation and automatic target recognition emphasizing the computational cost involved in the process. In order to obtain focused inverse synthetic aperture radar (ISAR) images certain signal processing algorithms must be applied to the information sensed by the radar. From actual data collected by radar the stages and algorithms needed to obtain ISAR images are revised, including high resolution range profile generation, motion compensation and ISAR formation. Target recognition is achieved by comparing the generated set of actual ISAR images with a database of ISAR images generated by electromagnetic software. High resolution radar image generation and target recognition processes are burdensome and time consuming, so to determine the most suitable implementation platform the analysis of the computational complexity is of great interest. To this end and since target identification must be completed in real time, computational burden of both processes the generation and comparison with a database is explained separately. Conclusions are drawn about implementation platforms and calculation efficiency in order to reduce time consumption in a possible future implementation.

  5. High-resolution and LIDAR imaging support to the Haiti earthquake relief effort

    NASA Astrophysics Data System (ADS)

    Messinger, David W.; van Aardt, Jan; McKeown, Don; Casterline, May; Faulring, Jason; Raqueño, Nina; Basener, Bill; Velez-Reyes, Miguel

    2010-08-01

    The Wildfire Airborne Sensor Program (WASP) is an imaging system designed, built, and operated by the RIT Center for Imaging Science. The system consists of four cameras: a high resolution color camera and SWIR, MWIR, and LWIR cameras. When flown with our corporate partners, Kucera International, the imaging system is combined with a high-resolution LIDAR. This combination provides a full-spectrum, multimodal data collection platform unique to RIT. Under funding by the World Bank, the WASP system was used to image over 250 sq. mi. in Haiti (approximately 15,000 visible and 45,000 infrared frames) from January 21 - 27, 2010 in support of the earthquake relief efforts. Priorities of collection were the area surrounding Port au Prince, the city of Leogane, several other badly damaged towns, and, at the request of the USGS, a high resolution LIDAR collection over the fault line. The imagery was used in the field by disaster relief workers and by collaborators at the University of Buffalo and ImageCat, Inc. to perform building damage and road network trafficability assessments. Additionally, large area mosaics and semi-automatic processing algorithms were developed for value-added product development. In particular, a methodology was developed to extract the locations of blue tarps (indicative of displaced persons) from the images. All imagery was made available to the public through outlets such as Google Earth, the University of Buffalo, the US Geological Survey, the United Nations, and other sites.

  6. VizieR Online Data Catalog: KOIs companions from high-resolution imaging (Hirsch+, 2017)

    NASA Astrophysics Data System (ADS)

    Hirsch, L. A.; Ciardi, D. R.; Howard, A. W.; Everett, M. E.; Furlan, E.; Saylors, M.; Horch, E. P.; Howell, S. B.; Teske, J.; Marcy, G. W.

    2017-07-01

    We report on 176 close (<2'') stellar companions detected with high-resolution imaging near 170 hosts of Kepler Objects of Interest (KOIs). Our sample consists of 170 stellar hosts of Kepler Objects of Interest (KOIs) observed with various high-resolution imaging campaigns. This sample was drawn from the overall sample of KOI stars observed with high-resolution imaging, described in the imaging compilation paper by Furlan et al. 2017 (Cat. J/AJ/153/71). We choose targets for this study by requiring that at least one companion was detected within 2'', and that the companion was detected in two or more filters, providing color information. We choose the 2'' separation limit to include all companions falling on the same Kepler pixel as the primary KOI host star. Furlan et al. 2017 (Cat. J/AJ/153/71) details the observations and measured differential magnitudes (Δm=m2-m1) for stars with high-resolution imaging, including our target systems. Each companion within 2'' must have at least two measured Δm values from the full set of filters used for follow-up observations, in order to be included in our sample. These filters include J-band, H-band, and K-band from adaptive optics imaging from the Keck/NIRC2, Palomar/PHARO, Lick/IRCAL, and MMT/Aries instruments; 562, 692 and 880nm filters from the Differential Speckle Survey Instrument (DSSI) at the Gemini North and WIYN telescopes; i and z bands from the AstraLux lucky imaging campaign at the Calar Alto 2.2m telescope; and LP600 and i bands from Palomar/RoboAO. We also include seeing-limited observations in the U-, B-, and V-bands from the UBV survey (Everett et al.) and "secure" detections (noise probability <10%) in the J-band from the UKIRT Kepler field survey. (3 data files).

  7. Feasibility of Transoral Robotic-Assisted High Resolution Microendoscopic Imaging of Oropharyngeal Squamous Cell Carcinoma

    PubMed Central

    Patsias, Alexis; Giraldez-Rodriguez, Laureano A.; Polydorides, Alexandros D.; Richards-Kortum, Rebecca; Anandasabapathy, Sharmila; Quang, Timothy; Sikora, Andrew G.; Miles, Brett A.

    2015-01-01

    Background Transoral robotic-assisted oncologic surgery of the head and neck offers promising functional results. Nonetheless, the efficacy of oncologic surgery remains critically dependent on obtaining negative margins. We aimed to integrate a miniaturized high resolution fiberoptic microendoscope (HRME), which provides real time histological assessment, with the da Vinci robotic system (Intuitive Surgical Inc., Sunnyvale, CA). Methods Three patients undergoing transoral robotic surgery were prospectively enrolled. Optical imaging of the oropharynx was performed intraoperatively with the robotic-assisted HRME. Results All patients underwent the procedure successfully with no complications. The HRME was successfully integrated with the Da Vinci Robotic system. Several sites of the oropharynx and associated malignancy were imaged, which correlated with the standard histopathological analysis. Conclusions Transoral robotic-assisted high resolution microendoscopic imaging of the oropharynx is a safe and technically feasible approach, providing a real time histological assessment and may serve as a valuable aid in oncologic surgery. PMID:25327825

  8. Fast blood flow visualization of high-resolution laser speckle imaging data using graphics processing unit.

    PubMed

    Liu, Shusen; Li, Pengcheng; Luo, Qingming

    2008-09-15

    Laser speckle contrast analysis (LASCA) is a non-invasive, full-field optical technique that produces two-dimensional map of blood flow in biological tissue by analyzing speckle images captured by CCD camera. Due to the heavy computation required for speckle contrast analysis, video frame rate visualization of blood flow which is essentially important for medical usage is hardly achieved for the high-resolution image data by using the CPU (Central Processing Unit) of an ordinary PC (Personal Computer). In this paper, we introduced GPU (Graphics Processing Unit) into our data processing framework of laser speckle contrast imaging to achieve fast and high-resolution blood flow visualization on PCs by exploiting the high floating-point processing power of commodity graphics hardware. By using GPU, a 12-60 fold performance enhancement is obtained in comparison to the optimized CPU implementations.

  9. REVIEW ARTICLE: Techniques for high resolution imaging of wood structure: a review

    NASA Astrophysics Data System (ADS)

    Bucur, V.

    2003-12-01

    High resolution imaging of wood requires the development of measurement techniques for nondestructive characterization of this material. The techniques, ranging from ionizing radiation to thermal techniques, microwaves, ultrasonics and nuclear magnetic resonance, provide excellent means of obtaining information about the internal structure of wood. High resolution images of wood structure can be obtained from a complete set of projections of relevant physical parameters such as x-ray attenuation, ultrasonic velocities, dielectric properties, etc. In this article the criterion selected for the description of the measurement techniques is the wavelength of the radiation which interacts with wood. The most relevant technique for the imaging of the cross section of the specimen under test will depend upon the particular application and material being studied: trees, logs, timber and wood-based composites.

  10. A High-resolution Multi-wavelength Simultaneous Imaging System with Solar Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Rao, Changhui; Zhu, Lei; Gu, Naiting; Rao, Xuejun; Zhang, Lanqiang; Bao, Hua; Kong, Lin; Guo, Youming; Zhong, Libo; Ma, Xue’an; Li, Mei; Wang, Cheng; Zhang, Xiaojun; Fan, Xinlong; Chen, Donghong; Feng, Zhongyi; Wang, Xiaoyun; Wang, Zhiyong

    2017-10-01

    A high-resolution multi-wavelength simultaneous imaging system from visible to near-infrared bands with a solar adaptive optics system, in which seven imaging channels, including the G band (430.5 nm), the Na i line (589 nm), the Hα line (656.3 nm), the TiO band (705.7 nm), the Ca ii IR line (854.2 nm), the He i line (1083 nm), and the Fe i line (1565.3 nm), are chosen, is developed to image the solar atmosphere from the photosphere layer to the chromosphere layer. To our knowledge, this is the solar high-resolution imaging system with the widest spectral coverage. This system was demonstrated at the 1 m New Vaccum Solar Telescope and the on-sky high-resolution observational results were acquired. In this paper, we will illustrate the design and performance of the imaging system. The calibration and the data reduction of the system are also presented.

  11. Automatic change detection using very high-resolution SAR images and prior knowledge about the scene

    NASA Astrophysics Data System (ADS)

    Villamil Lopez, C.; Kempf, T.; Speck, R.; Anglberger, H.; Stilla, U.

    2017-05-01

    Change detection using very high resolution SAR images is an important source of information for reconnaissance applications. Modern SAR sensors are capable of acquiring many images in short periods of time, which creates the need for a reliable automatic change detection method. In this paper, we will describe a new automatic change detection approach that combines very high resolution SAR images with prior knowledge about the imaged scene. In this case, the prior knowledge about the scene will come from vector maps, which can be obtained from a Geographic Information System (GIS). These vector maps will allow us to determine which regions are of interest for the change detection, and what kind of changes/objects can be expected there. The algorithm described in this paper will be applied to a time series of high resolution TerraSAR-X images of a port with military shipyards, and used to automatically detect ship activity and extract information about the detected ships. In this case, the vector maps were obtained from a Geographic Information System (GIS) containing map data from OpenStreetMap

  12. Disaster phenomena of Wenchuan earthquake in high resolution airborne synthetic aperture radar images

    NASA Astrophysics Data System (ADS)

    Wang, Chao; Zhang, Hong; Wu, Fan; Zhang, Bo; Tang, Yixian; Wu, Hongan; Wen, Xiaoyang; Yan, Dongmei

    2009-05-01

    The devastating Wenchuan Earthquake occurred in Sichuan Province, Southwestern China, with a magnitude of 8.0 on May 12, 2008. Most buildings along the seismic zone were ruined, resulting in infrastructure damage to factories, traffic facilities and power supplies. The earthquake also triggered geological disasters, such as landslides, debris flow, landslide lakes, etc. During the rescue campaign the remote sensing aircrafts of the Chinese Academy of Sciences (CAS), equipped with synthetic aperture radar (SAR) and optical sensors, flew over the disaster area and acquired many high resolution airborne SAR images. We first describe the basic characteristics of SAR imagery. The SAR images of buildings are simulated, and the backscattering mechanism of the buildings is analyzed. Finally, the various disaster phenomena are described and analyzed in the high resolution airborne SAR images. It is shown that certain phenomena of ruins could be identified clearly in high resolution SAR images in proper imaging conditions, while the functional destruction is quite difficult to detect. With calibrated data, the polarmetric SAR interferometry could be used to analyze the scattering mechanism and 3D distribution of the scattering center, which are redound to earthquake damage assessment.

  13. Interactive Change Detection Using High Resolution Remote Sensing Images Based on Active Learning with Gaussian Processes

    NASA Astrophysics Data System (ADS)

    Ru, Hui; Yu, Huai; Huang, Pingping; Yang, Wen

    2016-06-01

    Although there have been many studies for change detection, the effective and efficient use of high resolution remote sensing images is still a problem. Conventional supervised methods need lots of annotations to classify the land cover categories and detect their changes. Besides, the training set in supervised methods often has lots of redundant samples without any essential information. In this study, we present a method for interactive change detection using high resolution remote sensing images with active learning to overcome the shortages of existing remote sensing image change detection techniques. In our method, there is no annotation of actual land cover category at the beginning. First, we find a certain number of the most representative objects in unsupervised way. Then, we can detect the change areas from multi-temporal high resolution remote sensing images by active learning with Gaussian processes in an interactive way gradually until the detection results do not change notably. The artificial labelling can be reduced substantially, and a desirable detection result can be obtained in a few iterations. The experiments on Geo-Eye1 and WorldView2 remote sensing images demonstrate the effectiveness and efficiency of our proposed method.

  14. Interval TYPE-2 Fuzzy Based Neural Network for High Resolution Remote Sensing Image Segmentation

    NASA Astrophysics Data System (ADS)

    Wang, Chunyan; Xu, Aigong; Li, Chao; Zhao, Xuemei

    2016-06-01

    Recently, high resolution remote sensing image segmentation is a hot issue in image procesing procedures. However, it is a difficult task. The difficulties derive from the uncertainties of pixel segmentation and decision-making model. To this end, we take spatial relationship into consideration when constructing the interval type-2 fuzzy neural networks for high resolution remote sensing image segmentation. First, the proposed algorithm constructs a Gaussian model as a type-1 fuzzy model to describe the uncertainty contained in the image. Second, interval type-2 fuzzy model is obtained by blurring the mean and variance in type-1 model. The proposed interval type-2 model can strengthen the expression of uncertainty and simultaneously decrease the uncertainty in the decision model. Then the fuzzy membership function itself and its upper and lower fuzzy membership functions of the training samples are used as the input of neuron network which acts as the decision model in proposed algorithm. Finally, the relationship of neighbour pixels is taken into consideration and the fuzzy membership functions of the detected pixel and its neighbourhood are used to decide the class of each pixel to get the final segmentation result. The proposed algorithm, FCM and HMRF-FCM algorithm and an interval type-2 fuzzy neuron networks without spatial relationships are performed on synthetic and real high resolution remote sensing images. The qualitative and quantitative analyses demonstrate the efficient of the proposed algorithm, especially for homogeneous regions which contains a great difference in its gray level (for example forest).

  15. High-resolution magnetic resonance imaging of the lower extremity nerves.

    PubMed

    Burge, Alissa J; Gold, Stephanie L; Kuong, Sharon; Potter, Hollis G

    2014-02-01

    Magnetic resonance (MR) imaging of the nerves, commonly known as MR neurography is increasingly being used as noninvasive means of diagnosing peripheral nerve disease. High-resolution imaging protocols aimed at imaging the nerves of the hip, thigh, knee, leg, ankle, and foot can demonstrate traumatic or iatrogenic injury, tumorlike lesions, or entrapment of the nerves, causing a potential loss of motor and sensory function in the affected area. A thorough understanding of normal MR imaging and gross anatomy, as well as MR findings in the presence of peripheral neuropathies will aid in accurate diagnosis and ultimately help guide clinical management. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Localization of tissues in high-resolution digital anatomic pathology images

    NASA Astrophysics Data System (ADS)

    Alomari, Raja S.; Allen, Ron; Sabata, Bikash; Chaudhary, Vipin

    2009-02-01

    High resolution digital pathology images have a wide range of variability in color, shape, size, number, appearance, location, and texture. The segmentation problem is challenging in this environment. We introduce a hybrid method that combines parametric machine learning with heuristic methods for feature extraction as well as pre- and post-processing steps for localizing diverse tissues in slide images. The method uses features such as color, intensity, texture, and spatial distribution. We use principal component analysis for feature reduction and train a two layer back propagation neural network (with one hidden layer). We perform image labeling at pixel-level and achieve higher than 96% automatic localization accuracy on 294 test images.

  17. Snapshot imaging Fraunhofer line discriminator for detection of plant fluorescence

    NASA Astrophysics Data System (ADS)

    Gupta Roy, S.; Kudenov, M. W.

    2015-05-01

    Non-invasive quantification of plant health is traditionally accomplished using reflectance based metrics, such as the normalized difference vegetative index (NDVI). However, measuring plant fluorescence (both active and passive) to determine photochemistry of plants has gained importance. Due to better cost efficiency, lower power requirements, and simpler scanning synchronization, detecting passive fluorescence is preferred over active fluorescence. In this paper, we propose a high speed imaging approach for measuring passive plant fluorescence, within the hydrogen alpha Fraunhofer line at ~656 nm, using a Snapshot Imaging Fraunhofer Line Discriminator (SIFOLD). For the first time, the advantage of snapshot imaging for high throughput Fraunhofer Line Discrimination (FLD) is cultivated by our system, which is based on a multiple-image Fourier transform spectrometer and a spatial heterodyne interferometer (SHI). The SHI is a Sagnac interferometer, which is dispersion compensated using blazed diffraction gratings. We present data and techniques for calibrating the SIFOLD to any particular wavelength. This technique can be applied to quantify plant fluorescence at low cost and reduced complexity of data collection.

  18. High resolution crustal image of South California Continental Borderland: Reverse time imaging including multiples

    NASA Astrophysics Data System (ADS)

    Bian, A.; Gantela, C.

    2014-12-01

    Strong multiples were observed in marine seismic data of Los Angeles Regional Seismic Experiment (LARSE).It is crucial to eliminate these multiples in conventional ray-based or one-way wave-equation based depth image methods. As long as multiples contain information of target zone along travelling path, it's possible to use them as signal, to improve the illumination coverage thus enhance the image quality of structural boundaries. Reverse time migration including multiples is a two-way wave-equation based prestack depth image method that uses both primaries and multiples to map structural boundaries. Several factors, including source wavelet, velocity model, back ground noise, data acquisition geometry and preprocessing workflow may influence the quality of image. The source wavelet is estimated from direct arrival of marine seismic data. Migration velocity model is derived from integrated model building workflow, and the sharp velocity interfaces near sea bottom needs to be preserved in order to generate multiples in the forward and backward propagation steps. The strong amplitude, low frequency marine back ground noise needs to be removed before the final imaging process. High resolution reverse time image sections of LARSE Lines 1 and Line 2 show five interfaces: depth of sea-bottom, base of sedimentary basins, top of Catalina Schist, a deep layer and a possible pluton boundary. Catalina Schist shows highs in the San Clemente ridge, Emery Knoll, Catalina Ridge, under Catalina Basin on both the lines, and a minor high under Avalon Knoll. The high of anticlinal fold in Line 1 is under the north edge of Emery Knoll and under the San Clemente fault zone. An area devoid of any reflection features are interpreted as sides of an igneous plume.

  19. Applicability of a high-resolution small semiconductor gamma camera to small animal imaging.

    PubMed

    Kiyono, Yasushi; Kuge, Yuji; Katada, Yumiko; Kawashima, Hidekazu; Magata, Yasuhiro; Saji, Hideo

    2007-09-01

    Recently, small semiconductor gamma cameras (SSGCs) with high resolution and sensitivity, which are much more convenient to use as compared with SPECT and PET, have been developed for mapping the sentinel lymph node. The high resolution and sensitivity of the SSGCs may make them useful for small animal imaging. Therefore, we assessed the applicability of the SSGC to small animal imaging using a rat model of focal cerebral ischaemia. The right middle cerebral artery (MCA) of anaesthetized rats was occluded intraluminally with a nylon monofilament. Twenty-four hours after the occlusion, 99mTc-HMPAO (3.7 MBq) was injected and a static acquisition (5 min) was performed using the SSGC. Regions of interest (ROIs) were set on each hemisphere of the horizontal brain images. After the acquisition, the brains were removed and the radioactivity in each hemisphere was measured using an NaI scintillation counter. Reduced CBF in the right MCA territory was clearly visualized with the SSGC in vivo. The radioactivity in the ROIs determined by the SSGC was significantly correlated with that determined by the ex vivo counting method (P<0.001, R2=0.74). Furthermore, in both of the in-vivo imaging and ex-vivo counting methods, the right to left count ratio (R/L ratio) was significantly lower in the MCA-occluded rats than that in normal rats (MCA-occluded rats: 0.77+/-0.08, normal rats: 1.01+/-0.07, P<0.005). The SSGC clearly visualized and quantitatively detected the reduced CBF in MCA-occluded rats. Furthermore, these high resolution and sensitivity of SSGC can avoid the disadvantage of small animal imaging with PET and SPECT, such as a large mass injected tracer and the exposure of investigators to radiation. Thus, the high resolution and sensitivity of the SSGC make it useful for small animal imaging.

  20. The research of road and vehicle information extraction algorithm based on high resolution remote sensing image

    NASA Astrophysics Data System (ADS)

    Zhou, Tingting; Gu, Lingjia; Ren, Ruizhi; Cao, Qiong

    2016-09-01

    With the rapid development of remote sensing technology, the spatial resolution and temporal resolution of satellite imagery also have a huge increase. Meanwhile, High-spatial-resolution images are becoming increasingly popular for commercial applications. The remote sensing image technology has broad application prospects in intelligent traffic. Compared with traditional traffic information collection methods, vehicle information extraction using high-resolution remote sensing image has the advantages of high resolution and wide coverage. This has great guiding significance to urban planning, transportation management, travel route choice and so on. Firstly, this paper preprocessed the acquired high-resolution multi-spectral and panchromatic remote sensing images. After that, on the one hand, in order to get the optimal thresholding for image segmentation, histogram equalization and linear enhancement technologies were applied into the preprocessing results. On the other hand, considering distribution characteristics of road, the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used to suppress water and vegetation information of preprocessing results. Then, the above two processing result were combined. Finally, the geometric characteristics were used to completed road information extraction. The road vector extracted was used to limit the target vehicle area. Target vehicle extraction was divided into bright vehicles extraction and dark vehicles extraction. Eventually, the extraction results of the two kinds of vehicles were combined to get the final results. The experiment results demonstrated that the proposed algorithm has a high precision for the vehicle information extraction for different high resolution remote sensing images. Among these results, the average fault detection rate was about 5.36%, the average residual rate was about 13.60% and the average accuracy was approximately 91.26%.

  1. Multi-illumination Gabor holography recorded in a single camera snap-shot for high-resolution phase retrieval in digital in-line holographic microscopy

    NASA Astrophysics Data System (ADS)

    Sanz, Martin; Picazo-Bueno, Jose A.; Garcia, Javier; Micó, Vicente

    2015-05-01

    In this contribution we introduce MISHELF microscopy, a new concept and design of a lensless holographic microscope based on wavelength multiplexing, single hologram acquisition and digital image processing. The technique which name comes from Multi-Illumination Single-Holographic-Exposure Lensless Fresnel microscopy, is based on the simultaneous illumination and recording of three diffraction patterns in the Fresnel domain. In combination with a novel and fast iterative phase retrieval algorithm, MISHELF microscopy is capable of high-resolution (micron range) phase-retrieved (twin image elimination) biological imaging of dynamic events (video rate recording speed) since it avoids the time multiplexing needed for the in-line hologram sequence recording when using conventional phase-shifting or phase retrieval algorithms. MISHELF microscopy is validated using two different experimental layouts: one using RGB illumination and detection schemes and another using IRRB as illumination while keeping the RGB color camera as detection device. Preliminary experimental results are provided for both experimental layouts using a synthetic object (USAF resolution test target).

  2. High resolution in vivo intra-arterial imaging with optical coherence tomography

    PubMed Central

    Fujimoto, J; Boppart, S; Tearney, G; Bouma, B; Pitris, C; Brezinski, M

    1999-01-01

    BACKGROUND—Optical coherence tomography (OCT) is a new method of catheter based micron scale imaging. OCT is analogous to ultrasound, measuring the intensity of backreflected infrared light rather than sound waves.
OBJECTIVE—To demonstrate the ability of OCT to perform high resolution imaging of arterial tissue in vivo.
METHODS—OCT imaging of the abdominal aorta of New Zealand white rabbits was performed using a 2.9 F OCT imaging catheter. Using an ultrashort pulse laser as a light source for imaging, an axial resolution of 10 µm was achieved.
RESULTS—Imaging was performed at 4 frames/second and data were saved in either super VHS or digital format. Saline injections were required during imaging because of the signal attenuation caused by blood. Microstructure was sharply defined within the arterial wall and correlated with histology. Some motion artefacts were noted at 4 frames/second.
CONCLUSIONS—In vivo imaging of the rabbit aorta was demonstrated at a source resolution of 10 µm, but required the displacement of blood with saline. The high resolution of OCT allows imaging to be performed near the resolution of histopathology, offering the potential to have an impact both on the identification of high risk plaques and the guidance of interventional procedures.


Keywords: imaging; intravascular ultrasound; plaque rupture; optical coherence tomography PMID:10409522

  3. High resolution Cerenkov light imaging of induced positron distribution in proton therapy

    SciTech Connect

    Yamamoto, Seiichi Fujii, Kento; Morishita, Yuki; Okumura, Satoshi; Komori, Masataka; Toshito, Toshiyuki

    2014-11-01

    Purpose: In proton therapy, imaging of the positron distribution produced by fragmentation during or soon after proton irradiation is a useful method to monitor the proton range. Although positron emission tomography (PET) is typically used for this imaging, its spatial resolution is limited. Cerenkov light imaging is a new molecular imaging technology that detects the visible photons that are produced from high-speed electrons using a high sensitivity optical camera. Because its inherent spatial resolution is much higher than PET, the authors can measure more precise information of the proton-induced positron distribution with Cerenkov light imaging technology. For this purpose, they conducted Cerenkov light imaging of induced positron distribution in proton therapy. Methods: First, the authors evaluated the spatial resolution of our Cerenkov light imaging system with a {sup 22}Na point source for the actual imaging setup. Then the transparent acrylic phantoms (100 × 100 × 100 mm{sup 3}) were irradiated with two different proton energies using a spot scanning proton therapy system. Cerenkov light imaging of each phantom was conducted using a high sensitivity electron multiplied charge coupled device (EM-CCD) camera. Results: The Cerenkov light’s spatial resolution for the setup was 0.76 ± 0.6 mm FWHM. They obtained high resolution Cerenkov light images of the positron distributions in the phantoms for two different proton energies and made fused images of the reference images and the Cerenkov light images. The depths of the positron distribution in the phantoms from the Cerenkov light images were almost identical to the simulation results. The decay curves derived from the region-of-interests (ROIs) set on the Cerenkov light images revealed that Cerenkov light images can be used for estimating the half-life of the radionuclide components of positrons. Conclusions: High resolution Cerenkov light imaging of proton-induced positron distribution was possible. The

  4. Rayleigh-wave dispersive energy imaging using a high-resolution linear radon transform

    USGS Publications Warehouse

    Luo, Y.; Xia, J.; Miller, R.D.; Xu, Y.; Liu, J.; Liu, Q.

    2008-01-01

    Multichannel Analysis of Surface Waves (MASW) analysis is an efficient tool to obtain the vertical shear-wave profile. One of the key steps in the MASW method is to generate an image of dispersive energy in the frequency-velocity domain, so dispersion curves can be determined by picking peaks of dispersion energy. In this paper, we propose to image Rayleigh-wave dispersive energy by high-resolution linear Radon transform (LRT). The shot gather is first transformed along the time direction to the frequency domain and then the Rayleigh-wave dispersive energy can be imaged by high-resolution LRT using a weighted preconditioned conjugate gradient algorithm. Synthetic data with a set of linear events are presented to show the process of generating dispersive energy. Results of synthetic and real-world examples demonstrate that, compared with the slant stacking algorithm, high-resolution LRT can improve the resolution of images of dispersion energy by more than 50%. ?? Birkhaueser 2008.

  5. High-resolution interferometric radar images of equatorial spread F scattering structures using Capon's method

    NASA Astrophysics Data System (ADS)

    Zewdie, G. K.; Rodrigues, F. S.; Paula, E. R.

    2015-12-01

    Coherent backscatter radar imaging techniques use measurements made by multiple antenna baselines (visibility estimates) to infer the spatial distribution of the scatterers (brightness function) responsible for the observed echoes. It has been proposed that the Capon method for spectral estimation can be used for high-resolution estimation of the brightness distribution. We investigate the application of the Capon method to measurements made by a small (7-baseline) 30 MHz ionospheric coherent backscatter radar interferometer in Sao Luis, Brazil. The longest baseline of the interferometer is only 15 times the wavelength of radar signal (10 m), and the ionospheric radar soundings have been made using only 4-8 kW transmitters. Nevertheless, we have been able to obtain high-resolution (kilometric scales in the zonal direction) images of scattering structures during equatorial spread F (ESF) events over a wide field of view (+/- 10 degrees off zenith). We will present numerical simulations demonstrating the performance of the technique for the Sao Luis radar setup as well as results of the Capon technique applied to actual measurements. We will discuss the behavior of the ESF scattering structures as seen in the Capon images. The high-resolution images can assist our interpretation of plasma instabilities in the equatorial ionosphere and serve to test our ability to model the behavior of ionospheric irregularities during space weather events such as those associated with ESF.

  6. High-Resolution Imaging of Patients with Bietti Crystalline Dystrophy with CYP4V2 Mutation.

    PubMed

    Gocho, Kiyoko; Kameya, Shuhei; Akeo, Keiichiro; Kikuchi, Sachiko; Usui, Ayumi; Yamaki, Kunihiko; Hayashi, Takaaki; Tsuneoka, Hiroshi; Mizota, Atsushi; Takahashi, Hiroshi

    2014-01-01

    The purpose of this study was to determine the retinal morphology of eyes with Bietti crystalline dystrophy (BCD) associated with a CYP4V2 mutation using high-resolution imaging techniques. Three subjects with BCD underwent detailed ophthalmic examinations. High-resolution fundus images were obtained with an adaptive optics (AO) fundus camera. A common homozygous mutation was detected in the three patients. Funduscopic examination of the three patients revealed the presence of crystalline deposits in the retina, and all of the crystalline deposits were also detected in the infrared (IR) images. The crystals observed in the IR images were seen as bright reflective plaques located on the RPE layer in the SD-OCT images. The clusters of hyperreflective signals in the AO images corresponded to the crystals in the IR images. High-magnification AO images revealed that the clusters of hyperreflective signals consisted of circular spots that are similar to the signals of cone photoreceptors. Most of these circular spots were detected in healthy areas in the FAF images. There is a possibility that circular spots observed by AO are residual cone photoreceptors located over the crystals.

  7. Low-noise small-size microring ultrasonic detectors for high-resolution photoacoustic imaging

    PubMed Central

    Chen, Sung-Liang; Ling, Tao; Guo, L. Jay

    2011-01-01

    Small size polymer microring resonators have been exploited for photoacoustic (PA) imaging. To demonstrate the advantages of the wide acceptance angle of ultrasound detection of small size microrings, photoacoustic tomography (PAT), and delay-and-sum beamforming PA imaging was conducted. In PAT, we compared the imaging quality using different sizes of detectors with similar noise-equivalent pressures and the same wideband response: 500 μm hydrophone and 100, 60, and 40 μm microrings. The results show significantly improved imaging contrast and high resolution over the whole imaging region using smaller size detectors. The uniform high resolution in PAT imaging using 40 μm microrings indicates the potential to resolve microvasculature over a large imaging region. The improved lateral resolution of two-dimensional and three-dimensional delay-and-sum beamforming PA imaging using a synthetic array demonstrate another advantageous application of small microrings. The small microrings can also be applied to other ultrasound-related imaging applications. PMID:21639569

  8. High resolution in vivo intra-arterial imaging with optical coherence tomography.

    PubMed

    Fujimoto, J G; Boppart, S A; Tearney, G J; Bouma, B E; Pitris, C; Brezinski, M E

    1999-08-01

    Optical coherence tomography (OCT) is a new method of catheter based micron scale imaging. OCT is analogous to ultrasound, measuring the intensity of backreflected infrared light rather than sound waves. To demonstrate the ability of OCT to perform high resolution imaging of arterial tissue in vivo. OCT imaging of the abdominal aorta of New Zealand white rabbits was performed using a 2.9 F OCT imaging catheter. Using an ultrashort pulse laser as a light source for imaging, an axial resolution of 10 micrometer was achieved. Imaging was performed at 4 frames/second and data were saved in either super VHS or digital format. Saline injections were required during imaging because of the signal attenuation caused by blood. Microstructure was sharply defined within the arterial wall and correlated with histology. Some motion artefacts were noted at 4 frames/second. In vivo imaging of the rabbit aorta was demonstrated at a source resolution of 10 micrometer, but required the displacement of blood with saline. The high resolution of OCT allows imaging to be performed near the resolution of histopathology, offering the potential to have an impact both on the identification of high risk plaques and the guidance of interventional procedures.

  9. A fast and automatic mosaic method for high-resolution satellite images

    NASA Astrophysics Data System (ADS)

    Chen, Hongshun; He, Hui; Xiao, Hongyu; Huang, Jing

    2015-12-01

    We proposed a fast and fully automatic mosaic method for high-resolution satellite images. First, the overlapped rectangle is computed according to geographical locations of the reference and mosaic images and feature points on both the reference and mosaic images are extracted by a scale-invariant feature transform (SIFT) algorithm only from the overlapped region. Then, the RANSAC method is used to match feature points of both images. Finally, the two images are fused into a seamlessly panoramic image by the simple linear weighted fusion method or other method. The proposed method is implemented in C++ language based on OpenCV and GDAL, and tested by Worldview-2 multispectral images with a spatial resolution of 2 meters. Results show that the proposed method can detect feature points efficiently and mosaic images automatically.

  10. WAHRSIS: A low-cost high-resolution whole sky imager with near-infrared capabilities

    NASA Astrophysics Data System (ADS)

    Dev, Soumyabrata; Savoy, Florian M.; Lee, Yee Hui; Winkler, Stefan

    2014-05-01

    Cloud imaging using ground-based whole sky imagers is essential for a fine-grained understanding of cloud formations, which can be useful in many applications. Some such imagers are available commercially, but their cost is relatively high, and their flexibility is limited. Therefore, we built a new daytime Whole Sky Imager (WSI) called Wide Angle High-Resolution Sky Imaging System (WAHRSIS). The strengths of our new design are its simplicity, low manufacturing cost, and high image resolution. Our imager captures the entire hemisphere in a single picture using a digital camera with a Fish-eye lens. The camera was modified to capture light across the visible and near-infrared spectral ranges. This paper describes the design of the device as well as the geometric and radiometric calibration of the imaging system.

  11. Image Registration of High-Resolution Uav Data: the New Hypare Algorithm

    NASA Astrophysics Data System (ADS)

    Bahr, T.; Jin, X.; Lasica, R.; Giessel, D.

    2013-08-01

    Unmanned aerial vehicles play an important role in the present-day civilian and military intelligence. Equipped with a variety of sensors, such as SAR imaging modes, E/O- and IR sensor technology, they are due to their agility suitable for many applications. Hence, the necessity arises to use fusion technologies and to develop them continuously. Here an exact image-to-image registration is essential. It serves as the basis for important image processing operations such as georeferencing, change detection, and data fusion. Therefore we developed the Hybrid Powered Auto-Registration Engine (HyPARE). HyPARE combines all available spatial reference information with a number of image registration approaches to improve the accuracy, performance, and automation of tie point generation and image registration. We demonstrate this approach by the registration of 39 still images from a high-resolution image stream, acquired with a Aeryon Photo3S™ camera on an Aeryon Scout micro-UAV™.

  12. High-resolution X-ray imaging of Plasmodium falciparum-infected red blood cells.

    PubMed

    Williams, Garth J; Hanssen, Eric; Peele, Andrew G; Pfeifer, Mark A; Clark, Jesse; Abbey, Brian; Cadenazzi, Guido; de Jonge, Martin D; Vogt, Stefan; Tilley, Leann; Nugent, Keith A

    2008-10-01

    Methods for imaging cellular architecture and ultimately macromolecular complexes and individual proteins, within a cellular environment, are an important goal for cell and molecular biology. Coherent diffractive imaging (CDI) is a method of lensless imaging that can be applied to any individual finite object. A diffraction pattern from a single biological structure is recorded and an iterative Fourier transform between real space and reciprocal space is used to reconstruct information about the architecture of the sample to high resolution. As a test system for cellular imaging, we have applied CDI to an important human pathogen, the malaria parasite, Plasmodium falciparum. We have employed a novel CDI approach, known as Fresnel CDI, which uses illumination with a curved incident wavefront, to image red blood cells infected with malaria parasites. We have examined the intrinsic X-ray absorption contrast of these cells and compared them with cells contrasted with heavy metal stains or immunogold labeling. We compare CDI images with data obtained from the same cells using scanning electron microscopy, light microscopy, and scanning X-ray fluorescence microscopy. We show that CDI can offer new information both within and at the surface of complex biological specimens at a spatial resolution of better than 40 nm. and we demonstrate an imaging modality that conveniently combines scanning X-ray fluorescence microscopy with CDI. The data provide independent confirmation of the validity of the coherent diffractive image and demonstrate that CDI offers the potential to become an important and reliable new high-resolution imaging modality for cell biology. CDI can detect features at high resolution within unsectioned cells.

  13. MRO's High Resolution Imaging Science Experiment (HiRISE): Education and Public Outreach Plans

    NASA Technical Reports Server (NTRS)

    Gulick, V.; McEwen, A.; Delamere, W. A.; Eliason, E.; Grant, J.; Hansen, C.; Herkenhoff, K.; Keszthelyi, L.; Kirk, R.; Mellon, M.

    2003-01-01

    The High Resolution Imaging Experiment, described by McEwen et al. and Delamere et al., will fly on the Mars 2005 Orbiter. In conjunction with the NASA Mars E/PO program, the HiRISE team plans an innovative and aggressive E/PO effort to complement the unique high-resolution capabilities of the camera. The team is organizing partnerships with existing educational outreach programs and museums and plans to develop its own educational materials. In addition to other traditional E/PO activities and a strong web presence, opportunities will be provided for the public to participate in image targeting and science analysis. The main aspects of our program are summarized.

  14. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map

    PubMed Central

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen

    2015-01-01

    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate. PMID:26378543

  15. Mapping the electrostatic force field of single molecules from high-resolution scanning probe images

    PubMed Central

    Hapala, Prokop; Švec, Martin; Stetsovych, Oleksandr; van der Heijden, Nadine J.; Ondráček, Martin; van der Lit, Joost; Mutombo, Pingo; Swart, Ingmar; Jelínek, Pavel

    2016-01-01

    How electronic charge is distributed over a molecule determines to a large extent its chemical properties. Here, we demonstrate how the electrostatic force field, originating from the inhomogeneous charge distribution in a molecule, can be measured with submolecular resolution. We exploit the fact that distortions typically observed in high-resolution atomic force microscopy images are for a significant part caused by the electrostatic force acting between charges of the tip and the molecule of interest. By finding a geometrical transformation between two high-resolution AFM images acquired with two different tips, the electrostatic force field or potential over individual molecules and self-assemblies thereof can be reconstructed with submolecular resolution. PMID:27230940

  16. High-resolution Ceres High Altitude Mapping Orbit atlas derived from Dawn Framing Camera images

    NASA Astrophysics Data System (ADS)

    Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

    2016-09-01

    The Dawn spacecraft Framing Camera (FC) acquired over 2400 clear filter images of Ceres with a resolution of about 140 m/pixel during the six cycles in the High Altitude Mapping Orbit (HAMO) phase between August 18 and October 21, 2015. We ortho-rectified the images from the first cycle and produced a global, high-resolution, controlled photomosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 15 tiles mapped at a scale of 1:750,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The full atlas is available to the public through the Dawn Geographical Information System (GIS) web page

  17. High-resolution Ceres Low Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images

    NASA Astrophysics Data System (ADS)

    Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

    2017-06-01

    The Dawn spacecraft Framing Camera (FC) acquired over 31,300 clear filter images of Ceres with a resolution of about 35 m/pxl during the eleven cycles in the Low Altitude Mapping Orbit (LAMO) phase between December 16 2015 and August 8 2016. We ortho-rectified the images from the first four cycles and produced a global, high-resolution, uncontrolled photomosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 62 tiles mapped at a scale of 1:250,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The full atlas is available to the public through the Dawn Geographical Information System (GIS) web page [http://dawngis.dlr.de/atlas] and will become available through the NASA Planetary Data System (PDS) (http://pdssbn.astro.umd.edu/).

  18. High Resolution Surface Geometry and Albedo by Combining Laser Altimetry and Visible Images

    NASA Technical Reports Server (NTRS)

    Morris, Robin D.; vonToussaint, Udo; Cheeseman, Peter C.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    The need for accurate geometric and radiometric information over large areas has become increasingly important. Laser altimetry is one of the key technologies for obtaining this geometric information. However, there are important application areas where the observing platform has its orbit constrained by the other instruments it is carrying, and so the spatial resolution that can be recorded by the laser altimeter is limited. In this paper we show how information recorded by one of the other instruments commonly carried, a high-resolution imaging camera, can be combined with the laser altimeter measurements to give a high resolution estimate both of the surface geometry and its reflectance properties. This estimate has an accuracy unavailable from other interpolation methods. We present the results from combining synthetic laser altimeter measurements on a coarse grid with images generated from a surface model to re-create the surface model.

  19. MRO's High Resolution Imaging Science Experiment (HiRISE): Education and Public Outreach Plans

    NASA Technical Reports Server (NTRS)

    Gulick, V.; McEwen, A.; Delamere, W. A.; Eliason, E.; Grant, J.; Hansen, C.; Herkenhoff, K.; Keszthelyi, L.; Kirk, R.; Mellon, M.

    2003-01-01

    The High Resolution Imaging Experiment, described by McEwen et al. and Delamere et al., will fly on the Mars 2005 Orbiter. In conjunction with the NASA Mars E/PO program, the HiRISE team plans an innovative and aggressive E/PO effort to complement the unique high-resolution capabilities of the camera. The team is organizing partnerships with existing educational outreach programs and museums and plans to develop its own educational materials. In addition to other traditional E/PO activities and a strong web presence, opportunities will be provided for the public to participate in image targeting and science analysis. The main aspects of our program are summarized.

  20. Relationship Model Between Nightlight Data and Floor Area Ratio from High Resolution Images

    NASA Astrophysics Data System (ADS)

    Yan, M.; Xu, L.

    2017-09-01

    It is a hotpot that extraction the floor area ratio from high resolution remote sensing images. It is a development trend of using nightlight data to survey the urban social and economic information. This document aims to provide a conference relationship model for VIIRS/NPP nightlight data and floor Area Ratio from High Resolution ZY-3 Images. It shows that there is a lineal relationship between the shadow and the floor area ratio, and the R2 is 0.98. It shows that there is a quadratic polynomial relationship between the floor area ratio and the nightlight, and the R2 is 0.611. We can get a conclusion that, VIIRS/NPP nightlights data may show the floor area ratio in an extent at level of administrative street.

  1. Plastic embedding immunolabeled large-volume samples for three-dimensional high-resolution imaging.

    PubMed

    Gang, Yadong; Liu, Xiuli; Wang, Xiaojun; Zhang, Qi; Zhou, Hongfu; Chen, Ruixi; Liu, Ling; Jia, Yao; Yin, Fangfang; Rao, Gong; Chen, Jiadong; Zeng, Shaoqun

    2017-08-01

    High-resolution three-dimensional biomolecule distribution information of large samples is essential to understanding their biological structure and function. Here, we proposed a method combining large sample resin embedding with iDISCO immunofluorescence staining to acquire the profile of biomolecules with high spatial resolution. We evaluated the compatibility of plastic embedding with an iDISCO staining technique and found that the fluorophores and the neuronal fine structures could be well preserved in the Lowicryl HM20 resin, and that numerous antibodies and fluorescent tracers worked well upon Lowicryl HM20 resin embedding. Further, using fluorescence Micro-Optical sectioning tomography (fMOST) technology combined with ultra-thin slicing and imaging, we were able to image the immunolabeled large-volume tissues with high resolution.

  2. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map.

    PubMed

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen

    2015-09-11

    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate.

  3. Principles and simulations of high-resolution STM imaging with a flexible tip apex

    NASA Astrophysics Data System (ADS)

    Krejčí, Ondrej; Hapala, Prokop; Ondráček, Martin; Jelínek, Pavel

    2017-01-01

    We present a robust but still efficient simulation approach for high-resolution scanning tunneling microscopy (STM) with a flexible tip apex showing sharp submolecular features. The approach takes into account the electronic structure of the sample and tip as well as relaxation of the tip apex. We validate our model by achieving good agreement with various experimental images which allows us to explain the origin of several observed features. Namely, we have found that the high-resolution STM mechanism consists of standard STM imaging, convolving electronic states of the sample and the tip apex orbital structure, with the contrast heavily distorted by the relaxation of the flexible apex caused by interaction with the substrate.

  4. Plastic embedding immunolabeled large-volume samples for three-dimensional high-resolution imaging

    PubMed Central

    Gang, Yadong; Liu, Xiuli; Wang, Xiaojun; Zhang, Qi; Zhou, Hongfu; Chen, Ruixi; Liu, Ling; Jia, Yao; Yin, Fangfang; Rao, Gong; Chen, Jiadong; Zeng, Shaoqun

    2017-01-01

    High-resolution three-dimensional biomolecule distribution information of large samples is essential to understanding their biological structure and function. Here, we proposed a method combining large sample resin embedding with iDISCO immunofluorescence staining to acquire the profile of biomolecules with high spatial resolution. We evaluated the compatibility of plastic embedding with an iDISCO staining technique and found that the fluorophores and the neuronal fine structures could be well preserved in the Lowicryl HM20 resin, and that numerous antibodies and fluorescent tracers worked well upon Lowicryl HM20 resin embedding. Further, using fluorescence Micro-Optical sectioning tomography (fMOST) technology combined with ultra-thin slicing and imaging, we were able to image the immunolabeled large-volume tissues with high resolution. PMID:28856037

  5. Unsupervised Semantic Labeling Framework for Identification of Complex Facilities in High-resolution Remote Sensing Images

    SciTech Connect

    Vatsavai, Raju; Cheriyadat, Anil M; Gleason, Shaun Scott

    2010-01-01

    Nuclear proliferation is a major national security concern for many countries. Existing feature extraction and classification approaches are not suitable for monitoring proliferation activity using high-resolution multi-temporal remote sensing imagery. In this paper we present an unsupervised semantic labeling framework based on the Latent Dirichlet Allocation method. This framework is used to analyze over 70 images collected under different spatial and temporal settings over the globe representing two major semantic categories: nuclear and coal power plants. Initial experimental results show a reasonable discrimination of these two categories even though they share highly overlapping and common objects. This research also identified several research challenges associated with nuclear proliferation monitoring using high resolution remote sensing images.

  6. Thallium-201 myocardial imaging: comparison of the high sensitivity and high resolution collimators

    SciTech Connect

    Wynant, G.E.

    1981-03-01

    Thallium-201 myocardial images of 20 patients undergoing treadmill exercise were evaluated as to the ability of the high sensitivity collimator (HSC) to reveal perfusion defects compared to images obtained using the high resolution collimator (HRC). The study acquired 200,000 count images in the anterior, 45/sup 0/ left anterior oblique, and left lateral projections. Average acquisition times were: HSC 3.41 min, and HRC 6.08 min. Fifteen patients who had clearly visible perfusion defects using the HRC showed degraded definition or appreciable loss of definition of the same defects when using the HSC.

  7. Human oral mucosal epithelial cell sheets imaging with high-resolution phase-diversity homodyne OCT

    NASA Astrophysics Data System (ADS)

    Senda, Naoko; Osawa, Kentaro

    2015-03-01

    There is a need for development of non-invasive technique to evaluate regenerative tissues such as cell sheets for transplantation. We demonstrated non-invasive imaging inside living cell sheets of human oral mucosal epithelial cells by phase-diversity homodyne optical coherence tomography (OCT). The new method OCT developed in Hitachi enables cell imaging because of high resolution (axial resolution; ~2.6 μm, lateral resolution; ~1 μm, in the air). Nuclei inside cell sheets were imaged with sufficient spatial resolution to identify each cell. It suggested that the new method OCT could be useful for non-invasive cell sheet evaluation test.

  8. The Role of Imaging for Trigeminal Neuralgia: A Segmental Approach to High-Resolution MRI.

    PubMed

    Seeburg, Daniel P; Northcutt, Benjamin; Aygun, Nafi; Blitz, Ari M

    2016-07-01

    High-resolution MRI affords exquisite anatomic detail and allows radiologists to scrutinize the entire course of the trigeminal nerve (cranial nerve [CN] V). This article focuses first on the normal MRI appearance of the course of CN V and how best to image each segment. Special attention is then devoted to the role of MRI in presurgical evaluation of patients with neurovascular conflict and in identifying secondary causes of trigeminal neuralgia, including multiple sclerosis. Fundamental concepts in postsurgical imaging after neurovascular decompression are also addressed. Finally, how imaging has been used to better understand the etiology of trigeminal neuralgia is discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Rapid calibrated high-resolution hyperspectral imaging using tunable laser source

    NASA Astrophysics Data System (ADS)

    Nguyen, Lam K.; Margalith, Eli

    2009-05-01

    We present a novel hyperspectral imaging technique based on tunable laser technology. By replacing the broadband source and tunable filters of a typical NIR imaging instrument, several advantages are realized, including: high spectral resolution, highly variable field-of-views, fast scan-rates, high signal-to-noise ratio, and the ability to use optical fiber for efficient and flexible sample illumination. With this technique, high-resolution, calibrated hyperspectral images over the NIR range can be acquired in seconds. The performance of system features will be demonstrated on two example applications: detecting melamine contamination in wheat gluten and separating bovine protein from wheat protein in cattle feed.

  10. High-resolution diffusion kurtosis imaging at 3T enabled by advanced post-processing

    PubMed Central

    Mohammadi, Siawoosh; Tabelow, Karsten; Ruthotto, Lars; Feiweier, Thorsten; Polzehl, Jörg; Weiskopf, Nikolaus

    2015-01-01

    Diffusion Kurtosis Imaging (DKI) is more sensitive to microstructural differences and can be related to more specific micro-scale metrics (e.g., intra-axonal volume fraction) than diffusion tensor imaging (DTI), offering exceptional potential for clinical diagnosis and research into the white and gray matter. Currently DKI is acquired only at low spatial resolution (2–3 mm isotropic), because of the lower signal-to-noise ratio (SNR) and higher artifact level associated with the technically more demanding DKI. Higher spatial resolution of about 1 mm is required for the characterization of fine white matter pathways or cortical microstructure. We used restricted-field-of-view (rFoV) imaging in combination with advanced post-processing methods to enable unprecedented high-quality, high-resolution DKI (1.2 mm isotropic) on a clinical 3T scanner. Post-processing was advanced by developing a novel method for Retrospective Eddy current and Motion ArtifacT Correction in High-resolution, multi-shell diffusion data (REMATCH). Furthermore, we applied a powerful edge preserving denoising method, denoted as multi-shell orientation-position-adaptive smoothing (msPOAS). We demonstrated the feasibility of high-quality, high-resolution DKI and its potential for delineating highly myelinated fiber pathways in the motor cortex. REMATCH performs robustly even at the low SNR level of high-resolution DKI, where standard EC and motion correction failed (i.e., produced incorrectly aligned images) and thus biased the diffusion model fit. We showed that the combination of REMATCH and msPOAS increased the contrast between gray and white matter in mean kurtosis (MK) maps by about 35% and at the same time preserves the original distribution of MK values, whereas standard Gaussian smoothing strongly biases the distribution. PMID:25620906

  11. High-resolution diffusion kurtosis imaging at 3T enabled by advanced post-processing.

    PubMed

    Mohammadi, Siawoosh; Tabelow, Karsten; Ruthotto, Lars; Feiweier, Thorsten; Polzehl, Jörg; Weiskopf, Nikolaus

    2014-01-01

    Diffusion Kurtosis Imaging (DKI) is more sensitive to microstructural differences and can be related to more specific micro-scale metrics (e.g., intra-axonal volume fraction) than diffusion tensor imaging (DTI), offering exceptional potential for clinical diagnosis and research into the white and gray matter. Currently DKI is acquired only at low spatial resolution (2-3 mm isotropic), because of the lower signal-to-noise ratio (SNR) and higher artifact level associated with the technically more demanding DKI. Higher spatial resolution of about 1 mm is required for the characterization of fine white matter pathways or cortical microstructure. We used restricted-field-of-view (rFoV) imaging in combination with advanced post-processing methods to enable unprecedented high-quality, high-resolution DKI (1.2 mm isotropic) on a clinical 3T scanner. Post-processing was advanced by developing a novel method for Retrospective Eddy current and Motion ArtifacT Correction in High-resolution, multi-shell diffusion data (REMATCH). Furthermore, we applied a powerful edge preserving denoising method, denoted as multi-shell orientation-position-adaptive smoothing (msPOAS). We demonstrated the feasibility of high-quality, high-resolution DKI and its potential for delineating highly myelinated fiber pathways in the motor cortex. REMATCH performs robustly even at the low SNR level of high-resolution DKI, where standard EC and motion correction failed (i.e., produced incorrectly aligned images) and thus biased the diffusion model fit. We showed that the combination of REMATCH and msPOAS increased the contrast between gray and white matter in mean kurtosis (MK) maps by about 35% and at the same time preserves the original distribution of MK values, whereas standard Gaussian smoothing strongly biases the distribution.

  12. High resolution neutron imaging of water in the polymer electrolyte fuel cell membrane

    SciTech Connect

    Mukherjee, Partha P; Makundan, Rangachary; Spendelow, Jacob S; Borup, Rodney L; Hussey, D S; Jacobson, D L; Arif, M

    2009-01-01

    Water transport in the ionomeric membrane, typically Nafion{reg_sign}, has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, high resolution neutron imaging of the Nafion{reg_sign} membrane is presented in order to measure water content and through-plane gradients in situ under disparate temperature and humidification conditions.

  13. Collimator selection for SPECT brain imaging: the advantage of high resolution

    SciTech Connect

    Mueller, S.P.; Polak, J.F.; Kijewski, M.F.; Holman, B.L.

    1986-11-01

    We compared a prototype long-bore (LB) high-resolution collimator with a low-energy, general-purpose collimator (LEGP) using 99mTc and /sup 123/I. The LB collimator provided a 56% improvement in tomographic resolution (autocorrelation width) over the LEGP for 99mTc; for /sup 123/I, the gain was 79%, providing substantially improved contrast for small structures. The sensitivity of the LB collimator, however, is only 32% of that of the LEGP. The imaging tasks to be performed on (/sup 123/I)IMP brain scans involve localization and discrimination of small, high-contrast brain structures and detection of abnormalities in shape, size, or uptake, rather than simple detection of lesions. Observer performance in such higher-order imaging tasks is known to depend on high spatial resolution, even at the cost of sensitivity. Patient studies confirmed that, for resolution-limited tasks, the increase in resolution outweighs the increased noise due to a loss in sensitivity. When the tomographic resolution of the LB collimator was degraded by smoothing to that of the LEGP, the noise in the LB images was lower than that of the LEGP by a factor of 2.9 for the same imaging time, demonstrating the advantage of high-resolution detectors and a smooth reconstruction filter over low-resolution detectors without smoothing. Therefore, collimators designed for high resolution, even at substantial cost in sensitivity, are expected to yield significant improvements for brain SPECT. Geometric calculations show that commercially available low-energy, high-resolution cast collimators promise to meet these requirements.

  14. InSAR Forensics: Tracing InSAR Scatterers in High Resolution Optical Image

    NASA Astrophysics Data System (ADS)

    Wang, Yuanyuan; Zhu, XiaoXiang

    2015-05-01

    This paper presents a step towards a better interpretation of the scattering mechanism of different objects and their deformation histories in SAR interferometry (InSAR). The proposed technique traces individual SAR scatterer in high resolution optical images where their geometries, materials, and other properties can be better analyzed and classified. And hence scatterers of a same object can be analyzed in group, which brings us to a new level of InSAR deformation monitoring.

  15. High Resolution Imager (HRI) for the Roentgen Satellite (ROSAT) definition study

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The design of the high resolution imager (HRI) on HEAO 2 was modified for use in the instrument complement of the Roentgen Satellite (ROSAT). Mechanical models of the front end assembly, central electronics assembly, and detector assembly were used to accurately represent the HRI envelope for both fit checks and focal plane configuration studies. The mechanical and electrical interfaces were defined and the requirements for electrical ground support equipment were established. A summary description of the ROSAT telescope and mission is included.

  16. Motion immune diffusion imaging using augmented MUSE for high-resolution multi-shot EPI.

    PubMed

    Guhaniyogi, Shayan; Chu, Mei-Lan; Chang, Hing-Chiu; Song, Allen W; Chen, Nan-Kuei

    2016-02-01

    To develop new techniques for reducing the effects of microscopic and macroscopic patient motion in diffusion imaging acquired with high-resolution multishot echo-planar imaging. The previously reported multiplexed sensitivity encoding (MUSE) algorithm is extended to account for macroscopic pixel misregistrations, as well as motion-induced phase errors in a technique called augmented MUSE (AMUSE). Furthermore, to obtain more accurate quantitative diffusion-tensor imaging measures in the presence of subject motion, we also account for the altered diffusion encoding among shots arising from macroscopic motion. MUSE and AMUSE were evaluated on simulated and in vivo motion-corrupted multishot diffusion data. Evaluations were made both on the resulting imaging quality and estimated diffusion tensor metrics. AMUSE was found to reduce image blurring resulting from macroscopic subject motion compared to MUSE but yielded inaccurate tensor estimations when neglecting the altered diffusion encoding. Including the altered diffusion encoding in AMUSE produced better estimations of diffusion tensors. The use of AMUSE allows for improved image quality and diffusion tensor accuracy in the presence of macroscopic subject motion during multishot diffusion imaging. These techniques should facilitate future high-resolution diffusion imaging. © 2015 Wiley Periodicals, Inc.

  17. Quantitative 3D high resolution transmission ultrasound tomography: creating clinically relevant images (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wiskin, James; Klock, John; Iuanow, Elaine; Borup, Dave T.; Terry, Robin; Malik, Bilal H.; Lenox, Mark

    2017-03-01

    There has been a great deal of research into ultrasound tomography for breast imaging over the past 35 years. Few successful attempts have been made to reconstruct high-resolution images using transmission ultrasound. To this end, advances have been made in 2D and 3D algorithms that utilize either time of arrival or full wave data to reconstruct images with high spatial and contrast resolution suitable for clinical interpretation. The highest resolution and quantitative accuracy result from inverse scattering applied to full wave data in 3D. However, this has been prohibitively computationally expensive, meaning that full inverse scattering ultrasound tomography has not been considered clinically viable. Here we show the results of applying a nonlinear inverse scattering algorithm to 3D data in a clinically useful time frame. This method yields Quantitative Transmission (QT) ultrasound images with high spatial and contrast resolution. We reconstruct sound speeds for various 2D and 3D phantoms and verify these values with independent measurements. The data are fully 3D as is the reconstruction algorithm, with no 2D approximations. We show that 2D reconstruction algorithms can introduce artifacts into the QT breast image which are avoided by using a full 3D algorithm and data. We show high resolution gross and microscopic anatomic correlations comparing cadaveric breast QT images with MRI to establish imaging capability and accuracy. Finally, we show reconstructions of data from volunteers, as well as an objective visual grading analysis to confirm clinical imaging capability and accuracy.

  18. Progress in BazookaSPECT: High-Resolution, Dynamic Scintigraphy with Large-Area Imagers

    PubMed Central

    Miller, Brian W.; Barber, H. Bradford; Barrett, Harrison H.; Liu, Zhonglin; Nagarkar, Vivek V.; Furenlid, Lars R.

    2015-01-01

    We present recent progress in BazookaSPECT, a high-resolution, photon-counting gamma-ray detector. It is a new class of scintillation detector that combines columnar scintillators, image intensifiers, and CCD (charge-coupled device) or CMOS (complementary metal-oxide semiconductors) sensors for high-resolution imaging. A key feature of the BazookaSPECT paradigm is the capability to easily design custom detectors in terms of the desired intrinsic detector resolution and event detection rate. This capability is possible because scintillation light is optically amplified by the image intensifier prior to being imaging onto the CCD/CMOS sensor, thereby allowing practically any consumer-grade CCD/CMOS sensor to be used for gamma-ray imaging. Recent efforts have been made to increase the detector area by incorporating fiber-optic tapers between the scintillator and image intensifier, resulting in a 16× increase in detector area. These large-area BazookaSPECT detectors can be used for full-body imaging and we present preliminary results of their use as dynamic scintigraphy imagers for mice and rats. Also, we discuss ongoing and future developments in BazookaSPECT and the improved event-detection rate capability that is achieved using Graphics Processing Units (GPUs), multi-core processors, and new high-speed, USB 3.0 CMOS cameras. PMID:26346514

  19. Relative Orientation and Modified Piecewise Epipolar Resampling for High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Gong, K.; Fritsch, D.

    2017-05-01

    High resolution, optical satellite sensors are boosted to a new era in the last few years, because satellite stereo images at half meter or even 30cm resolution are available. Nowadays, high resolution satellite image data have been commonly used for Digital Surface Model (DSM) generation and 3D reconstruction. It is common that the Rational Polynomial Coefficients (RPCs) provided by the vendors have rough precision and there is no ground control information available to refine the RPCs. Therefore, we present two relative orientation methods by using corresponding image points only: the first method will use quasi ground control information, which is generated from the corresponding points and rough RPCs, for the bias-compensation model; the second method will estimate the relative pointing errors on the matching image and remove this error by an affine model. Both methods do not need ground control information and are applied for the entire image. To get very dense point clouds, the Semi-Global Matching (SGM) method is an efficient tool. However, before accomplishing the matching process the epipolar constraints are required. In most conditions, satellite images have very large dimensions, contrary to the epipolar geometry generation and image resampling, which is usually carried out in small tiles. This paper also presents a modified piecewise epipolar resampling method for the entire image without tiling. The quality of the proposed relative orientation and epipolar resampling method are evaluated, and finally sub-pixel accuracy has been achieved in our work.

  20. Progress in BazookaSPECT: high-resolution dynamic scintigraphy with large-area imagers

    NASA Astrophysics Data System (ADS)

    Miller, Brian W.; Barber, H. Bradford; Barrett, Harrison H.; Liu, Zhonglin; Nagarkar, Vivek V.; Furenlid, Lars R.

    2012-10-01

    We present recent progress in BazookaSPECT, a high-resolution, photon-counting gamma-ray detector. It is a new class of scintillation detector that combines columnar scintillators, image intensifiers, and CCD (charge- coupled device) or CMOS (complementary metal-oxide semiconductors) sensors for high-resolution imaging. A key feature of the BazookaSPECT paradigm is the capability to easily design custom detectors in terms of the desired intrinsic detector resolution and event detection rate. This capability is possible because scintillation light is optically amplfied by the image intensifier prior to being imaging onto the CCD/CMOS sensor, thereby allowing practically any consumer-grade CCD/CMOS sensor to be used for gamma-ray imaging. Recent efforts have been made to increase the detector area by incorporating fiber-optic tapers between the scintillator and image intensi_er, resulting in a 16x increase in detector area. These large-area BazookaSPECT detectors can be used for full-body imaging and we present preliminary results of their use as dynamic scintigraphy imagers for mice and rats. Also, we discuss ongoing and future developments in BazookaSPECT and the improved event- detection rate capability that is achieved using Graphics Processing Units (GPUs), multi-core processors, and new high-speed, USB 3.0 CMOS cameras.

  1. Progress in BazookaSPECT: High-Resolution, Dynamic Scintigraphy with Large-Area Imagers.

    PubMed

    Miller, Brian W; Barber, H Bradford; Barrett, Harrison H; Liu, Zhonglin; Nagarkar, Vivek V; Furenlid, Lars R

    2012-08-12

    We present recent progress in BazookaSPECT, a high-resolution, photon-counting gamma-ray detector. It is a new class of scintillation detector that combines columnar scintillators, image intensifiers, and CCD (charge-coupled device) or CMOS (complementary metal-oxide semiconductors) sensors for high-resolution imaging. A key feature of the BazookaSPECT paradigm is the capability to easily design custom detectors in terms of the desired intrinsic detector resolution and event detection rate. This capability is possible because scintillation light is optically amplified by the image intensifier prior to being imaging onto the CCD/CMOS sensor, thereby allowing practically any consumer-grade CCD/CMOS sensor to be used for gamma-ray imaging. Recent efforts have been made to increase the detector area by incorporating fiber-optic tapers between the scintillator and image intensifier, resulting in a 16× increase in detector area. These large-area BazookaSPECT detectors can be used for full-body imaging and we present preliminary results of their use as dynamic scintigraphy imagers for mice and rats. Also, we discuss ongoing and future developments in BazookaSPECT and the improved event-detection rate capability that is achieved using Graphics Processing Units (GPUs), multi-core processors, and new high-speed, USB 3.0 CMOS cameras.

  2. High resolution computational on-chip imaging of biological samples using sparsity constraint (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rivenson, Yair; Wu, Chris; Wang, Hongda; Zhang, Yibo; Ozcan, Aydogan

    2017-03-01

    Microscopic imaging of biological samples such as pathology slides is one of the standard diagnostic methods for screening various diseases, including cancer. These biological samples are usually imaged using traditional optical microscopy tools; however, the high cost, bulkiness and limited imaging throughput of traditional microscopes partially restrict their deployment in resource-limited settings. In order to mitigate this, we previously demonstrated a cost-effective and compact lens-less on-chip microscopy platform with a wide field-of-view of >20-30 mm^2. The lens-less microscopy platform has shown its effectiveness for imaging of highly connected biological samples, such as pathology slides of various tissue samples and smears, among others. This computational holographic microscope requires a set of super-resolved holograms acquired at multiple sample-to-sensor distances, which are used as input to an iterative phase recovery algorithm and holographic reconstruction process, yielding high-resolution images of the samples in phase and amplitude channels. Here we demonstrate that in order to reconstruct clinically relevant images with high resolution and image contrast, we require less than 50% of the previously reported nominal number of holograms acquired at different sample-to-sensor distances. This is achieved by incorporating a loose sparsity constraint as part of the iterative holographic object reconstruction. We demonstrate the success of this sparsity-based computational lens-less microscopy platform by imaging pathology slides of breast cancer tissue and Papanicolaou (Pap) smears.

  3. Repeated, noninvasive, high resolution spectral domain optical coherence tomography imaging of zebrafish embryos

    PubMed Central

    Kagemann, Larry; Ishikawa, Hiroshi; Zou, Jian; Charukamnoetkanok, Puwat; Wollstein, Gadi; Townsend, Kelly A.; Gabriele, Michelle L.; Bahary, Nathan; Wei, Xiangyun; Fujimoto, James G.

    2008-01-01

    Purpose To demonstrate a new imaging method for high resolution spectral domain optical coherence tomography (SD-OCT) for small animal developmental imaging. Methods Wildtype zebrafish that were 24, 48, 72, and 120 h post fertilization (hpf) and nok gene mutant (48 hpf) embryos were imaged in vivo. Three additional embryos were imaged twice, once at 72 hpf and again at 120 hpf. Images of the developing eye, brain, heart, whole body, proximal yolk sac, distal yolk sac, and tail were acquired. Three-dimensional OCT data sets (501×180 axial scans) were obtained as well as oversampled frames (8,100 axial scans) and repeated line scans (180 repeated frames). Scan volumes ranged from 750×750 µm to 3×3 mm, each 1.8 mm thick. Three-dimenstional data sets allowed construction of C-mode slabs of the embryo. Results SD-OCT provided ultra-high resolution visualization of the eye, brain, heart, ear, and spine of the developing embryo as early as 24 hpf, and allowed development to be documented in each of these organ systems in consecutive sessions. Repeated line scanning with averaging optimized the visualization of static and dynamic structures contained in SD-OCT images. Structural defects caused by a mutation in the nok gene were readily observed as impeded ocular development, and enlarged pericardial cavities. Conclusions SD-OCT allowed noninvasive, in vivo, ultra-high resolution, high-speed imaging of zebrafish embryos in their native state. The ability to measure structural and functional features repeatedly on the same specimen, without the need to sacrifice, promises to be a powerful tool in small animal developmental imaging. PMID:19052656

  4. High resolution OCT image generation using super resolution via sparse representation

    NASA Astrophysics Data System (ADS)

    Asif, Muhammad; Akram, Muhammad Usman; Hassan, Taimur; Shaukat, Arslan; Waqar, Razi

    2017-02-01

    In this paper we propose a technique for obtaining a high resolution (HR) image from a single low resolution (LR) image -using joint learning dictionary - on the basis of image statistic research. It suggests that with an appropriate choice of an over-complete dictionary, image patches can be well represented as a sparse linear combination. Medical imaging for clinical analysis and medical intervention is being used for creating visual representations of the interior of a body, as well as visual representation of the function of some organs or tissues (physiology). A number of medical imaging techniques are in use like MRI, CT scan, X-rays and Optical Coherence Tomography (OCT). OCT is one of the new technologies in medical imaging and one of its uses is in ophthalmology where it is being used for analysis of the choroidal thickness in the eyes in healthy and disease states such as age-related macular degeneration, central serous chorioretinopathy, diabetic retinopathy and inherited retinal dystrophies. We have proposed a technique for enhancing the OCT images which can be used for clearly identifying and analyzing the particular diseases. Our method uses dictionary learning technique for generating a high resolution image from a single input LR image. We train two joint dictionaries, one with OCT images and the second with multiple different natural images, and compare the results with previous SR technique. Proposed method for both dictionaries produces HR images which are comparatively superior in quality with the other proposed method of SR. Proposed technique is very effective for noisy OCT images and produces up-sampled and enhanced OCT images.

  5. High-resolution, continuous field-of-view (FOV), non-rotating imaging system

    NASA Technical Reports Server (NTRS)

    Huntsberger, Terrance L. (Inventor); Stirbl, Robert C. (Inventor); Aghazarian, Hrand (Inventor); Padgett, Curtis W. (Inventor)

    2010-01-01

    A high resolution CMOS imaging system especially suitable for use in a periscope head. The imaging system includes a sensor head for scene acquisition, and a control apparatus inclusive of distributed processors and software for device-control, data handling, and display. The sensor head encloses a combination of wide field-of-view CMOS imagers and narrow field-of-view CMOS imagers. Each bank of imagers is controlled by a dedicated processing module in order to handle information flow and image analysis of the outputs of the camera system. The imaging system also includes automated or manually controlled display system and software for providing an interactive graphical user interface (GUI) that displays a full 360-degree field of view and allows the user or automated ATR system to select regions for higher resolution inspection.

  6. Mechanism of high-resolution STM, AFM and IETS-STM imaging with functionalized tips

    NASA Astrophysics Data System (ADS)

    Temirov, R.; Hapala, P.; Tautz, F. S.; Jelinek, P.

    2015-03-01

    High-resolution AFM and STM with functionalized tips is well established, but a detailed understanding of the image mechanism is still missing. Moreover, recently this family of imaging techniques has been complemented by a method based on inelastic electron tunneling spectroscopy. Here we present a comprehensive mechanical and transport simulation model that explains essentially all image features in functionalized tip STM, AFM and IETS-STM. Important aspects of the mechanism are: (i) Images are dominantly determined by Pauli repulsion, (ii) in STM and IETS STM this force signal is transduced into an elastic or inelastic conductance signal, (iii) probe particle relaxation leads to image sharpening, (iv) the apparent imaging of hydrogen bonds can be explained by a relaxation effect, and (v) electrostatic forces may also influence the image contrast.

  7. Optical contrast enhancement of high-resolution ocular fundus imaging in vivo using polarimetry

    NASA Astrophysics Data System (ADS)

    Yang, Hansheng; Rao, Xuejun; Zhang, Yudong

    2007-11-01

    The adaptive optics (AO) retina imaging was performed with contrast enhancement by characterizing polarization parameters of the living retina. A removable pair of polarization state generating unit near the optical source and analysis unit near the CCD camera was incorporated into the basic 37-channle deformable mirror AO microscopic ophthalmoscope. Double-pass imaging polarimetry of the human eye was carried out, then incomplete Mueller matrix was calculated and analyzed to optimize the retina imaging condition using polarized light, which caused the subretinal structures with different polarization properties to emerge from the scattering light background, so the contrast of the image can be substantially enhanced. This method is demonstrated briefly and its validity was tested in the laboratory. The high-resolution images of ocular fundus are compared with 8-frame-averaging images we obtained prior to this method. The experiment results now show improved visualization of fundus structures to some extent without greatly sacrificing image resolution.

  8. Multi-Sensor Fusion of Infrared and Electro-Optic Signals for High Resolution Night Images

    PubMed Central

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-01-01

    Electro-optic (EO) image sensors exhibit the properties of high resolution and low noise level at daytime, but they do not work in dark environments. Infrared (IR) image sensors exhibit poor resolution and cannot separate objects with similar temperature. Therefore, we propose a novel framework of IR image enhancement based on the information (e.g., edge) from EO images, which improves the resolution of IR images and helps us distinguish objects at night. Our framework superimposing/blending the edges of the EO image onto the corresponding transformed IR image improves their resolution. In this framework, we adopt the theoretical point spread function (PSF) proposed by Hardie et al. for the IR image, which has the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we design an inverse filter for the proposed PSF and use it for the IR image transformation. The framework requires four main steps: (1) inverse filter-based IR image transformation; (2) EO image edge detection; (3) registration; and (4) blending/superimposing of the obtained image pair. Simulation results show both blended and superimposed IR images, and demonstrate that blended IR images have better quality over the superimposed images. Additionally, based on the same steps, simulation result shows a blended IR image of better quality when only the original IR image is available. PMID:23112602

  9. Multi-sensor fusion of infrared and electro-optic signals for high resolution night images.

    PubMed

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-01-01

    Electro-optic (EO) image sensors exhibit the properties of high resolution and low noise level at daytime, but they do not work in dark environments. Infrared (IR) image sensors exhibit poor resolution and cannot separate objects with similar temperature. Therefore, we propose a novel framework of IR image enhancement based on the information (e.g., edge) from EO images, which improves the resolution of IR images and helps us distinguish objects at night. Our framework superimposing/blending the edges of the EO image onto the corresponding transformed IR image improves their resolution. In this framework, we adopt the theoretical point spread function (PSF) proposed by Hardie et al. for the IR image, which has the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we design an inverse filter for the proposed PSF and use it for the IR image transformation. The framework requires four main steps: (1) inverse filter-based IR image transformation; (2) EO image edge detection; (3) registration; and (4) blending/superimposing of the obtained image pair. Simulation results show both blended and superimposed IR images, and demonstrate that blended IR images have better quality over the superimposed images. Additionally, based on the same steps, simulation result shows a blended IR image of better quality when only the original IR image is available.

  10. FFT-enhanced IHS transform method for fusing high-resolution satellite images

    USGS Publications Warehouse

    Ling, Y.; Ehlers, M.; Usery, E.L.; Madden, M.

    2007-01-01

    Existing image fusion techniques such as the intensity-hue-saturation (IHS) transform and principal components analysis (PCA) methods may not be optimal for fusing the new generation commercial high-resolution satellite images such as Ikonos and QuickBird. One problem is color distortion in the fused image, which causes visual changes as well as spectral differences between the original and fused images. In this paper, a fast Fourier transform (FFT)-enhanced IHS method is developed for fusing new generation high-resolution satellite images. This method combines a standard IHS transform with FFT filtering of both the panchromatic image and the intensity component of the original multispectral image. Ikonos and QuickBird data are used to assess the FFT-enhanced IHS transform method. Experimental results indicate that the FFT-enhanced IHS transform method may improve upon the standard IHS transform and the PCA methods in preserving spectral and spatial information. ?? 2006 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).

  11. High Resolution Imaging of Satellites with Ground-Based 10-m Astronomical Telescopes

    SciTech Connect

    Marois, C

    2007-01-04

    High resolution imaging of artificial satellites can play an important role in current and future space endeavors. One such use is acquiring detailed images that can be used to identify or confirm damage and aid repair plans. It is shown that a 10-m astronomical telescope equipped with an adaptive optics system (AO) to correct for atmospheric turbulence using a natural guide star can acquire high resolution images of satellites in low-orbits using a fast shutter and a near-infrared camera even if the telescope is not capable of tracking satellites. With the telescope pointing towards the satellite projected orbit and less than 30 arcsec away from a guide star, multiple images of the satellite are acquired on the detector using the fast shutter. Images can then be shifted and coadded by post processing to increase the satellite signal to noise ratio. Using the Keck telescope typical Strehl ratio and anisoplanatism angle as well as a simple diffusion/reflection model for a satellite 400 km away observed near Zenith at sunset or sunrise, it is expected that such system will produced > 10{sigma} K-band images at a resolution of 10 cm inside a 60 arcsec diameter field of view. If implemented, such camera could deliver the highest resolution satellite images ever acquired from the ground.

  12. Design and fabrication of a passive droplet dispenser for portable high resolution imaging system.

    PubMed

    Kamal, Tahseen; Watkins, Rachel; Cen, Zijian; Rubinstein, Jaden; Kong, Gary; Lee, Woei Ming

    2017-01-27

    Moldless lens manufacturing techniques using standard droplet dispensing technology often require precise control over pressure to initiate fluid flow and control droplet formation. We have determined a series of interfacial fluid parameters optimised using standard 3D printed tools to extract, dispense and capture a single silicone droplet that is then cured to obtain high quality lenses. The dispensing process relies on the recapitulation of liquid dripping action (Rayleigh-Plateau instability) and the capturing method uses the interplay of gravitational force, capillary forces and liquid pinning to control the droplet shape. The key advantage of the passive lens fabrication approach is rapid scale-up using 3D printing by avoiding complex dispensing tools. We characterise the quality of the lenses fabricated using the passive approach by measuring wavefront aberration and high resolution imaging. The fabricated lenses are then integrated into a portable imaging system; a wearable thimble imaging device with a detachable camera housing, that is constructed for field imaging. This paper provides the full exposition of steps, from lens fabrication to imaging platform, necessary to construct a standalone high resolution imaging system. The simplicity of our methodology can be implemented using a regular desktop 3D printer and commercially available digital imaging systems.

  13. Mitigating atmospheric effects in high-resolution infra-red surveillance imagery with bispectral speckle imaging

    SciTech Connect

    Carrano, C J

    2006-05-30

    Obtaining a high-resolution image of an object or scene from a long distance away can be very problematic, even with the best optical system. This is because atmospheric blurring and distortion will limit the resolution and contrast of high-resolution imaging systems with substantial sized apertures over horizontal and slant paths. Much of the horizontal and slant-path surveillance imagery we have previously collected and successfully enhanced has been collected at visible wavelengths where atmospheric effects are the strongest. Imaging at longer wavelengths has the benefit of seeing through obscurants or even at night, but even though the atmospheric effects are noticeably reduced, they are nevertheless present, especially near the ground. This paper will describe our recent work on enhanced infrared (IR) surveillance using bispectral speckle imaging. Bispectral speckle imaging in this context is an image postprocessing algorithm that aims to solve the atmospheric blurring and distortion problem of imaging through horizontal or slant path turbulence. A review of the algorithm as well as descriptions of the IR camera and optical systems used in our data collections will be given. Examples of horizontal and slant-path imagery before and after speckle processing will also be presented to demonstrate the resolution improvement gained by the processing. Comparisons of IR imagery to visible wavelength imagery of the same target under the same conditions will be shown to demonstrate the tradeoffs of going to longer wavelengths.

  14. Design and fabrication of a passive droplet dispenser for portable high resolution imaging system

    NASA Astrophysics Data System (ADS)

    Kamal, Tahseen; Watkins, Rachel; Cen, Zijian; Rubinstein, Jaden; Kong, Gary; Lee, Woei Ming

    2017-01-01

    Moldless lens manufacturing techniques using standard droplet dispensing technology often require precise control over pressure to initiate fluid flow and control droplet formation. We have determined a series of interfacial fluid parameters optimised using standard 3D printed tools to extract, dispense and capture a single silicone droplet that is then cured to obtain high quality lenses. The dispensing process relies on the recapitulation of liquid dripping action (Rayleigh-Plateau instability) and the capturing method uses the interplay of gravitational force, capillary forces and liquid pinning to control the droplet shape. The key advantage of the passive lens fabrication approach is rapid scale-up using 3D printing by avoiding complex dispensing tools. We characterise the quality of the lenses fabricated using the passive approach by measuring wavefront aberration and high resolution imaging. The fabricated lenses are then integrated into a portable imaging system; a wearable thimble imaging device with a detachable camera housing, that is constructed for field imaging. This paper provides the full exposition of steps, from lens fabrication to imaging platform, necessary to construct a standalone high resolution imaging system. The simplicity of our methodology can be implemented using a regular desktop 3D printer and commercially available digital imaging systems.

  15. Design and fabrication of a passive droplet dispenser for portable high resolution imaging system

    PubMed Central

    Kamal, Tahseen; Watkins, Rachel; Cen, Zijian; Rubinstein, Jaden; Kong, Gary; Lee, Woei Ming

    2017-01-01

    Moldless lens manufacturing techniques using standard droplet dispensing technology often require precise control over pressure to initiate fluid flow and control droplet formation. We have determined a series of interfacial fluid parameters optimised using standard 3D printed tools to extract, dispense and capture a single silicone droplet that is then cured to obtain high quality lenses. The dispensing process relies on the recapitulation of liquid dripping action (Rayleigh-Plateau instability) and the capturing method uses the interplay of gravitational force, capillary forces and liquid pinning to control the droplet shape. The key advantage of the passive lens fabrication approach is rapid scale-up using 3D printing by avoiding complex dispensing tools. We characterise the quality of the lenses fabricated using the passive approach by measuring wavefront aberration and high resolution imaging. The fabricated lenses are then integrated into a portable imaging system; a wearable thimble imaging device with a detachable camera housing, that is constructed for field imaging. This paper provides the full exposition of steps, from lens fabrication to imaging platform, necessary to construct a standalone high resolution imaging system. The simplicity of our methodology can be implemented using a regular desktop 3D printer and commercially available digital imaging systems. PMID:28128365

  16. High-resolution Fiber-optic Microendoscopy for in situ Cellular Imaging

    PubMed Central

    Pierce, Mark; Yu, Dihua; Richards-Kortum, Rebecca

    2011-01-01

    Many biological and clinical studies require the longitudinal study and analysis of morphology and function with cellular level resolution. Traditionally, multiple experiments are run in parallel, with individual samples removed from the study at sequential time points for evaluation by light microscopy. Several intravital techniques have been developed, with confocal, multiphoton, and second harmonic microscopy all demonstrating their ability to be used for imaging in situ 1. With these systems, however, the required infrastructure is complex and expensive, involving scanning laser systems and complex light sources. Here we present a protocol for the design and assembly of a high-resolution microendoscope which can be built in a day using off-the-shelf components for under US$5,000. The platform offers flexibility in terms of image resolution, field-of-view, and operating wavelength, and we describe how these parameters can be easily modified to meet the specific needs of the end user. We and others have explored the use of the high-resolution microendoscope (HRME) in in vitro cell culture 2-5, in excised 6 and living animal tissues 2,5, and in human tissues in vivo 2,7. Users have reported the use of several different fluorescent contrast agents, including proflavine 2-4, benzoporphyrin-derivative monoacid ring A (BPD-MA) 5, and fluoroscein 6,7, all of which have received full, or investigational approval from the FDA for use in human subjects. High-resolution microendoscopy, in the form described here, may appeal to a wide range of researchers working in the basic and clinical sciences. The technique offers an effective and economical approach which complements traditional benchtop microscopy, by enabling the user to perform high-resolution, longitudinal imaging in situ. PMID:21248707

  17. High-resolution fiber-optic microendoscopy for in situ cellular imaging.

    PubMed

    Pierce, Mark; Yu, Dihua; Richards-Kortum, Rebecca

    2011-01-11

    Many biological and clinical studies require the longitudinal study and analysis of morphology and function with cellular level resolution. Traditionally, multiple experiments are run in parallel, with individual samples removed from the study at sequential time points for evaluation by light microscopy. Several intravital techniques have been developed, with confocal, multiphoton, and second harmonic microscopy all demonstrating their ability to be used for imaging in situ. With these systems, however, the required infrastructure is complex and expensive, involving scanning laser systems and complex light sources. Here we present a protocol for the design and assembly of a high-resolution microendoscope which can be built in a day using off-the-shelf components for under US$5,000. The platform offers flexibility in terms of image resolution, field-of-view, and operating wavelength, and we describe how these parameters can be easily modified to meet the specific needs of the end user. We and others have explored the use of the high-resolution microendoscope (HRME) in in vitro cell culture, in excised and living animal tissues, and in human tissues in vivo. Users have reported the use of several different fluorescent contrast agents, including proflavine, benzoporphyrin-derivative monoacid ring A (BPD-MA), and fluoroscein, all of which have received full, or investigational approval from the FDA for use in human subjects. High-resolution microendoscopy, in the form described here, may appeal to a wide range of researchers working in the basic and clinical sciences. The technique offers an effective and economical approach which complements traditional benchtop microscopy, by enabling the user to perform high-resolution, longitudinal imaging in situ.

  18. Video rate spectral imaging using a coded aperture snapshot spectral imager.

    PubMed

    Wagadarikar, Ashwin A; Pitsianis, Nikos P; Sun, Xiaobai; Brady, David J

    2009-04-13

    We have previously reported on coded aperture snapshot spectral imagers (CASSI) that can capture a full frame spectral image in a snapshot. Here we describe the use of CASSI for spectral imaging of a dynamic scene at video rate. We describe significant advances in the design of the optical system, system calibration procedures and reconstruction method. The new optical system uses a double Amici prism to achieve an in-line, direct view configuration, resulting in a substantial improvement in image quality. We describe NeAREst, an algorithm for estimating the instantaneous three-dimensional spatio-spectral data cube from CASSI's two-dimensional array of encoded and compressed measurements. We utilize CASSI's snapshot ability to demonstrate a spectral image video of multi-colored candles with live flames captured at 30 frames per second.

  19. Object-oriented recognition of high-resolution remote sensing image

    NASA Astrophysics Data System (ADS)

    Wang, Yongyan; Li, Haitao; Chen, Hong; Xu, Yuannan

    2016-01-01

    With the development of remote sensing imaging technology and the improvement of multi-source image's resolution in satellite visible light, multi-spectral and hyper spectral , the high resolution remote sensing image has been widely used in various fields, for example military field, surveying and mapping, geophysical prospecting, environment and so forth. In remote sensing image, the segmentation of ground targets, feature extraction and the technology of automatic recognition are the hotspot and difficulty in the research of modern information technology. This paper also presents an object-oriented remote sensing image scene classification method. The method is consist of vehicles typical objects classification generation, nonparametric density estimation theory, mean shift segmentation theory, multi-scale corner detection algorithm, local shape matching algorithm based on template. Remote sensing vehicles image classification software system is designed and implemented to meet the requirements .

  20. Occluded target viewing and identification high-resolution 2D imaging laser radar

    NASA Astrophysics Data System (ADS)

    Grasso, Robert J.; Dippel, George F.; Cecchetti, Kristen D.; Wikman, John C.; Drouin, David P.; Egbert, Paul I.

    2007-09-01

    BAE SYSTEMS has developed a high-resolution 2D imaging laser radar (LADAR) system that has proven its ability to detect and identify hard targets in occluded environments, through battlefield obscurants, and through naturally occurring image-degrading atmospheres. Limitations of passive infrared imaging for target identification using medium wavelength infrared (MWIR) and long wavelength infrared (LWIR) atmospheric windows are well known. Of particular concern is that as wavelength is increased the aperture must be increased to maintain resolution, hence, driving apertures to be very larger for long-range identification; impractical because of size, weight, and optics cost. Conversely, at smaller apertures and with large f-numbers images may become photon starved with long integration times. Here, images are most susceptible to distortion from atmospheric turbulence, platform vibration, or both. Additionally, long-range identification using passive thermal imaging is clutter limited arising from objects in close proximity to the target object.

  1. Change detection in high resolution SAR images based on multiscale texture features

    NASA Astrophysics Data System (ADS)

    Wen, Caihuan; Gao, Ziqiang

    2011-12-01

    This paper studied on change detection algorithm of high resolution (HR) Synthetic Aperture Radar (SAR) images based on multi-scale texture features. Firstly, preprocessed multi-temporal Terra-SAR images were decomposed by 2-D dual tree complex wavelet transform (DT-CWT), and multi-scale texture features were extracted from those images. Then, log-ratio operation was utilized to get difference images, and the Bayes minimum error theory was used to extract change information from difference images. Lastly, precision assessment was done. Meanwhile, we compared with the result of method based on texture features extracted from gray-level cooccurrence matrix (GLCM). We had a conclusion that, change detection algorithm based on multi-scale texture features has a great more improvement, which proves an effective method to change detect of high spatial resolution SAR images.

  2. Motion immune diffusion imaging using augmented MUSE (AMUSE) for high-resolution multi-shot EPI

    PubMed Central

    Guhaniyogi, Shayan; Chu, Mei-Lan; Chang, Hing-Chiu; Song, Allen W.; Chen, Nan-kuei

    2015-01-01

    Purpose To develop new techniques for reducing the effects of microscopic and macroscopic patient motion in diffusion imaging acquired with high-resolution multi-shot EPI. Theory The previously reported Multiplexed Sensitivity Encoding (MUSE) algorithm is extended to account for macroscopic pixel misregistrations as well as motion-induced phase errors in a technique called Augmented MUSE (AMUSE). Furthermore, to obtain more accurate quantitative DTI measures in the presence of subject motion, we also account for the altered diffusion encoding among shots arising from macroscopic motion. Methods MUSE and AMUSE were evaluated on simulated and in vivo motion-corrupted multi-shot diffusion data. Evaluations were made both on the resulting imaging quality and estimated diffusion tensor metrics. Results AMUSE was found to reduce image blurring resulting from macroscopic subject motion compared to MUSE, but yielded inaccurate tensor estimations when neglecting the altered diffusion encoding. Including the altered diffusion encoding in AMUSE produced better estimations of diffusion tensors. Conclusion The use of AMUSE allows for improved image quality and diffusion tensor accuracy in the presence of macroscopic subject motion during multi-shot diffusion imaging. These techniques should facilitate future high-resolution diffusion imaging. PMID:25762216

  3. Automatic detection of sub-km craters in high resolution planetary images

    NASA Astrophysics Data System (ADS)

    Urbach, Erik R.; Stepinski, Tomasz F.

    2009-06-01

    Impact craters are among the most studied geomorphic planetary features because they yield information about the past geological processes and provide a tool for measuring relative ages of observed geologic formations. Surveying impact craters is an important task which traditionally has been achieved by means of visual inspection of images. The shear number of smaller craters present in high resolution images makes visual counting of such craters impractical. In this paper we present a method that brings together a novel, efficient crater identification algorithm with a data processing pipeline; together they enable a fully automatic detection of sub-km craters in large panchromatic images. The technical details of the method are described and its performance is evaluated using a large, 12.5 m/pixel image centered on the Nanedi Valles on Mars. The detection percentage of the method is ˜70%. The system detects over 35,000 craters in this image; average crater density is 0.5craters/km2, but localized spots of much higher crater density are present. The method is designed to produce "million craters" global catalogs of sub-km craters on Mars and other planets wherever high resolution images are available. Such catalogs could be utilized for deriving high spatial resolution and high temporal precision stratigraphy on regional or even planetary scale.

  4. Tapping-mode atomic force microscopy produces faithful high-resolution images of protein surfaces.

    PubMed Central

    Möller, C; Allen, M; Elings, V; Engel, A; Müller, D J

    1999-01-01

    Compared to contact-mode atomic force microscopy (CMAFM), tapping-mode atomic force microscopy (TMAFM) has the advantage of allowing imaging surfaces of macromolecules, even when they are only weakly attached to the support. In this study, TMAFM is applied to two different regular protein layers whose structures are known to great detail, the purple membrane from Halobacterium salinarum and the hexagonally packed intermediate (HPI) layer from Deinococcus radiodurans, to assess the faithfulness of high-resolution TMAFM images. Topographs exhibited a lateral resolution between 1.1 and 1. 5 nm and a vertical resolution of approximately 0.1 nm. For all protein surfaces, TMAFM and CMAFM topographs were in excellent agreement. TMAFM was capable of imaging the fragile polypeptide loop connecting the transmembrane alpha-helices E and F of bacteriorhodopsin in its native extended conformation. The standard deviation (SD) of averages calculated from TMAFM topographs exhibited an enhanced minimum (between 0.1 and 0.9 nm) that can be assigned to the higher noise of the raw data. However, the SD difference, indicating the flexibility of protein subunits, exhibited an excellent agreement between the two imaging modes. This demonstrates that the recently invented imaging-mode TMAFM has the ability to faithfully record high-resolution images and has sufficient sensitivity to contour individual peptide loops without detectable deformations. PMID:10423460

  5. Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner

    PubMed Central

    Kakinuma, Ryutaro; Moriyama, Noriyuki; Muramatsu, Yukio; Gomi, Shiho; Suzuki, Masahiro; Nagasawa, Hirobumi; Kusumoto, Masahiko; Aso, Tomohiko; Muramatsu, Yoshihisa; Tsuchida, Takaaki; Tsuta, Koji; Maeshima, Akiko Miyagi; Tochigi, Naobumi; Watanabe, Shun-ichi; Sugihara, Naoki; Tsukagoshi, Shinsuke; Saito, Yasuo; Kazama, Masahiro; Ashizawa, Kazuto; Awai, Kazuo; Honda, Osamu; Ishikawa, Hiroyuki; Koizumi, Naoya; Komoto, Daisuke; Moriya, Hiroshi; Oda, Seitaro; Oshiro, Yasuji; Yanagawa, Masahiro; Tomiyama, Noriyuki; Asamura, Hisao

    2015-01-01

    Purpose The image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT) scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT) scanners. Materials and Methods This study was approved by the institutional review board. A U-HRCT scanner prototype with 0.25 mm x 4 rows and operating at 120 mAs was used. The C-HRCT images were obtained using a 0.5 mm x 16 or 0.5 mm x 64 detector-row CT scanner operating at 150 mAs. Images from both scanners were reconstructed at 0.1-mm intervals; the slice thickness was 0.25 mm for the U-HRCT scanner and 0.5 mm for the C-HRCT scanners. For both scanners, the display field of view was 80 mm. The image noise of each scanner was evaluated using a phantom. U-HRCT and C-HRCT images of 53 images selected from 37 lung nodules were then observed and graded using a 5-point score by 10 board-certified thoracic radiologists. The images were presented to the observers randomly and in a blinded manner. Results The image noise for U-HRCT (100.87 ± 0.51 Hounsfield units [HU]) was greater than that for C-HRCT (40.41 ± 0.52 HU; P < .0001). The image quality of U-HRCT was graded as superior to that of C-HRCT (P < .0001) for all of the following parameters that were examined: margins of subsolid and solid nodules, edges of solid components and pulmonary vessels in subsolid nodules, air bronchograms, pleural indentations, margins of pulmonary vessels, edges of bronchi, and interlobar fissures. Conclusion Despite a larger image noise, the prototype U-HRCT scanner had a significantly better image quality than the C-HRCT scanners. PMID:26352144

  6. Image processing enhancement of high-resolution TEM micrographs of nanometer-size metal particles

    NASA Technical Reports Server (NTRS)

    Artal, P.; Avalos-Borja, M.; Soria, F.; Poppa, H.; Heinemann, K.

    1989-01-01

    The high-resolution TEM detectability of lattice fringes from metal particles supported on substrates is impeded by the substrate itself. Single value decomposition (SVD) and Fourier filtering (FFT) methods were applied to standard high resolution micrographs to enhance lattice resolution from particles as well as from crystalline substrates. SVD produced good results for one direction of fringes, and it can be implemented as a real-time process. Fourier methods are independent of azimuthal directions and allow separation of particle lattice planes from those pertaining to the substrate, which makes it feasible to detect possible substrate distortions produced by the supported particle. This method, on the other hand, is more elaborate, requires more computer time than SVD and is, therefore, less likely to be used in real-time image processing applications.

  7. Remote sensing of mesospheric winds with the High-Resolution Doppler Imager

    NASA Technical Reports Server (NTRS)

    Hays, Paul B.; Abreu, V. J.; Burrage, M. D.; Gell, D. A.; Grassi, H. J.; Marshall, A. R.; Morton, Y. T.; Ortland, D. A.; Skinner, W. R.; Wu, D. L.

    1992-01-01

    Observations of the winds in the upper atmosphere obtained with the High-Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) are discussed. This instrument is a very stable high-resolution triple-etalon Fabry-Perot interferometer, which is used to observe the slight Doppler shifts of absorption and emission lines in the O2 Atmospheric bands induced by atmospheric motions. Preliminary observations indicate that the winds in the mesosphere and lower thermosphere are a mixture of migrating and non-migrating tides, and planetary-scale waves. The mean meridional winds are dominated by the 1,1 diurnal tide which is easily extracted from the daily zonal means of the satellite observations. The daily mean zonal winds are a mixture of the diurnal tide and a zonal flow which is consistent with theoretical expectations.

  8. Image processing enhancement of high-resolution TEM micrographs of nanometer-size metal particles

    NASA Technical Reports Server (NTRS)

    Artal, P.; Avalos-Borja, M.; Soria, F.; Poppa, H.; Heinemann, K.

    1989-01-01

    The high-resolution TEM detectability of lattice fringes from metal particles supported on substrates is impeded by the substrate itself. Single value decomposition (SVD) and Fourier filtering (FFT) methods were applied to standard high resolution micrographs to enhance lattice resolution from particles as well as from crystalline substrates. SVD produced good results for one direction of fringes, and it can be implemented as a real-time process. Fourier methods are independent of azimuthal directions and allow separation of particle lattice planes from those pertaining to the substrate, which makes it feasible to detect possible substrate distortions produced by the supported particle. This method, on the other hand, is more elaborate, requires more computer time than SVD and is, therefore, less likely to be used in real-time image processing applications.

  9. A New Framework for Quality Assessment of High-Resolution Fingerprint Images.

    PubMed

    Teixeira, Raoni F S; Leite, Neucimar J

    2017-10-01

    The quality assessment of sets of features extracted from patterns of epidermal ridges on our fingers is a biometric challenge problem with implications on questions concerning security, privacy and identity fraud. In this work, we introduced a new methodology to analyze the quality of high-resolution fingerprint images containing sets of fingerprint pores. Our approach takes into account the spatial interrelationship between the considered features and some basic transformations involving point process and anisotropic analysis. We proposed two new quality index algorithms following spatial and structural classes of analysis. These algorithms have proved to be effective as a performance predictor and as a filter excluding low-quality features in a recognition process. The experiments using error reject curves show that the proposed approaches outperform the state-of-the-art quality assessment algorithm for high-resolution fingerprint recognition, besides defining a new method for reconstructing their friction ridge phases in a very consistent way.

  10. High Resolution Three-Dimensional MR Imaging of the Skull Base: Compartments, Boundaries, and Critical Structures.

    PubMed

    Blitz, Ari Meir; Aygun, Nafi; Herzka, Daniel A; Ishii, Masaru; Gallia, Gary L

    2017-01-01

    High-resolution 3D MRI of the skull base allows for a more detailed and accurate assessment of normal anatomic structures as well as the location and extent of skull base pathologies than has previously been possible. This article describes the techniques employed for high-resolution skull base MRI including pre- and post-contrast constructive interference in the steady state (CISS) imaging and their utility for evaluation of the many small structures of the skull base, focusing on those regions and concepts most pertinent to localization of cranial nerve palsies and in providing pre-operative guidance and post-operative assessment. The concept of skull base compartments as a means of conceptualizing the various layers of the skull base and their importance in assessment of masses of the skull base is discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals

    DOEpatents

    Smither, Robert K [Hinsdale, IL

    2008-12-23

    A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

  12. High resolution X-ray diffraction imaging of lead tin telluride

    NASA Technical Reports Server (NTRS)

    Steiner, Bruce; Dobbyn, Ronald C.; Black, David; Burdette, Harold; Kuriyama, Masao; Spal, Richard; Simchick, Richard; Fripp, Archibald

    1991-01-01

    High resolution X-ray diffraction images of two directly comparable crystals of lead tin telluride, one Bridgman-grown on Space Shuttle STS 61A and the other terrestrially Bridgman-grown under similar conditions from identical material, present different subgrain structure. In the terrestrial, sample 1 the appearance of an elaborate array of subgrains is closely associated with the intrusion of regions that are out of diffraction in all of the various images. The formation of this elaborate subgrain structure is inhibited by growth in microgravity.

  13. Applying high resolution remote sensing image and DEM to falling boulder hazard assessment

    NASA Astrophysics Data System (ADS)

    Huang, Changqing; Shi, Wenzhong; Ng, K. C.

    2005-10-01

    Boulder fall hazard assessing generally requires gaining the boulder information. The extensive mapping and surveying fieldwork is a time-consuming, laborious and dangerous conventional method. So this paper proposes an applying image processing technology to extract boulder and assess boulder fall hazard from high resolution remote sensing image. The method can replace the conventional method and extract the boulder information in high accuracy, include boulder size, shape, height and the slope and aspect of its position. With above boulder information, it can be satisfied for assessing, prevention and cure boulder fall hazard.

  14. High resolution x-ray medical sequential image acquisition and processing system based on PCI interface

    NASA Astrophysics Data System (ADS)

    Lu, Dongming; Chen, Qian; Gu, Guohua

    2003-11-01

    In the field of medical application, it is of great importance to adopt digital image processing technique. Based on the characteristics of medical image, we introduced the digital image processing method to the X-ray imaging system, and developed a high resolution x-ray medical sequential image acquisition and processing system that employs image enhancer and CCD. This system consists of three basic modules, namely sequential image acquisition, data transfer and system control, and image processing. Under the control of FPGA (Field Programmable Gate Array), images acquired by the front-end circuit are transmitted to a PC through high speed PCI bus, and then optimized by the image processing program. The software kits, which include PCI Device Driver and Image Processing Package, are developed with Visual C++ Language based on Windows OS. In this paper, we present a general introduction to the principle and the operating procedure of X-ray Sequential Image Acquisition and Processing System, with special emphasis on the key issues of the hardware design. In addition, the context, principle, status quo and the digitizing trend of X-ray Imaging are explained succinctly. Finally, the preliminary experimental results are shown to demonstrate that the system is capable of achieving high quality X-ray sequential images.

  15. High-resolution 3D X-ray imaging of intracranial nitinol stents.

    PubMed

    Snoeren, Rudolph M; Söderman, Michael; Kroon, Johannes N; Roijers, Ruben B; de With, Peter H N; Babic, Drazenko

    2012-02-01

    To assess an optimized 3D imaging protocol for intracranial nitinol stents in 3D C-arm flat detector imaging. For this purpose, an image quality simulation and an in vitro study was carried out. Nitinol stents of various brands were placed inside an anthropomorphic head phantom, using iodine contrast. Experiments with objects were preceded by image quality and dose simulations. We varied X-ray imaging parameters in a commercially interventional X-ray system to set 3D image quality in the contrast-noise-sharpness space. Beam quality was varied to evaluate contrast of the stents while keeping absorbed dose below recommended values. Two detector formats were used, paired with an appropriate pixel size and X-ray focus size. Zoomed reconstructions were carried out and snapshot images acquired. High contrast spatial resolution was assessed with a CT phantom. We found an optimal protocol for imaging intracranial nitinol stents. Contrast resolution was optimized for nickel-titanium-containing stents. A high spatial resolution larger than 2.1 lp/mm allows struts to be visualized. We obtained images of stents of various brands and a representative set of images is shown. Independent of the make, struts can be imaged with virtually continuous strokes. Measured absorbed doses are shown to be lower than 50 mGy Computed Tomography Dose Index (CTDI). By balancing the modulation transfer of the imaging components and tuning the high-contrast imaging capabilities, we have shown that thin nitinol stent wires can be reconstructed with high contrast-to-noise ratio and good detail, while keeping radiation doses within recommended values. Experimental results compare well with imaging simulations.

  16. Solid-state fluoroscopic imager for high-resolution angiography: Parallel-cascaded linear systems analysis

    PubMed Central

    Vedantham, Srinivasan; Karellas, Andrew; Suryanarayanan, Sankararaman

    2008-01-01

    Cascaded linear systems based modeling techniques have been used in the past to predict important system parameters that have a direct impact on image quality. Such models are also useful in optimizing system parameters to improve image quality. In this work, detailed analysis of a solid-state fluoroscopic imaging system intended for high-resolution angiography is presented with the use of such a model. The imaging system analyzed through this model uses four 8×8 cm three-side buttable interlined charge-coupled devices (CCDs) specifically designed for high-resolution angiography and tiled in a seamless fashion to achieve a field of view (FOV) of 16×16 cm. Larger FOVs can be achieved by tiling more CCDs in a similar manner. The system employs a CsI:Tl scintillator coupled to the CCDs by straight (nontapering) fiberoptics and can potentially be operated in 78, 156, or 234 μm pixel pitch modes. The system parameters analyzed through this model include presampling modulation transfer function, noise power spectrum, and detective quantum efficiency (DQE). The results of the simulations performed indicate that DQE(0) in excess of 0.6 is achievable, with the imager operating at 156 μm pixel pitch, 30 frames/s, and employing a 450-μm-thick CsI:Tl scintillator, even at a low fluoroscopic exposure rate of 1 μR/frame. Further, at a nominal fluoroscopic exposure rate of 2.5 μR/frame there was no noticeable degradation of the DQE even at the 78 μm pixel pitch mode suggesting that it is feasible to perform high-resolution angiography hitherto unattainable in clinical practice. PMID:15191318

  17. Solid-state fluoroscopic imager for high-resolution angiography: parallel-cascaded linear systems analysis.

    PubMed

    Vedantham, Srinivasan; Karellas, Andrew; Suryanarayanan, Sankararaman

    2004-05-01

    Cascaded linear systems based modeling techniques have been used in the past to predict important system parameters that have a direct impact on image quality. Such models are also useful in optimizing system parameters to improve image quality. In this work, detailed analysis of a solid-state fluoroscopic imaging system intended for high-resolution angiography is presented with the use of such a model. The imaging system analyzed through this model uses four 8 x 8 cm three-side buttable interlined charge-coupled devices (CCDs) specifically designed for high-resolution angiography and tiled in a seamless fashion to achieve a field of view (FOV) of 16 x 16 cm. Larger FOVs can be achieved by tiling more CCDs in a similar manner. The system employs a CsI:Tl scintillator coupled to the CCDs by straight (nontapering) fiberoptics and can potentially be operated in 78, 156, or 234 microm pixel pitch modes. The system parameters analyzed through this model include presampling modulation transfer function, noise power spectrum, and detective quantum efficiency (DQE). The results of the simulations performed indicate that DQE(0) in excess of 0.6 is achievable, with the imager operating at 156 microm pixel pitch, 30 frames/s, and employing a 450-microm-thick CsI:Tl scintillator, even at a low fluoroscopic exposure rate of 1 microR/frame. Further, at a nominal fluoroscopic exposure rate of 2.5 microR/frame there was no noticeable degradation of the DQE even at the 78 microm pixel pitch mode suggesting that it is feasible to perform high-resolution angiography hitherto unattainable in clinical practice.

  18. A low-cost, high-resolution, video-rate imaging optical radar

    SciTech Connect

    Sackos, J.T.; Nellums, R.O.; Lebien, S.M.; Diegert, C.F.; Grantham, J.W.; Monson, T.

    1998-04-01

    Sandia National Laboratories has developed a unique type of portable low-cost range imaging optical radar (laser radar or LADAR). This innovative sensor is comprised of an active floodlight scene illuminator and an image intensified CCD camera receiver. It is a solid-state device (no moving parts) that offers significant size, performance, reliability, and simplicity advantages over other types of 3-D imaging sensors. This unique flash LADAR is based on low cost, commercially available hardware, and is well suited for many government and commercial uses. This paper presents an update of Sandia`s development of the Scannerless Range Imager technology and applications, and discusses the progress that has been made in evolving the sensor into a compact, low, cost, high-resolution, video rate Laser Dynamic Range Imager.

  19. Label-free high-resolution imaging of live cells with deconvolved spatial light interference microscopy.

    PubMed

    Haldar, Justin P; Wang, Zhuo; Popescu, Gabriel; Liang, Zhi-Pei

    2010-01-01

    Spatial light interference microscopy (SLIM) is a powerful new quantitative phase optical imaging technique that can be used for studying live cells without the need for exogenous contrast agents. This paper proposes a novel deconvolution-based approach to reconstructing SLIM data, which dramatically improves the visual quality of the images. The proposed deconvolution formulation is tailored to the physics of SLIM imaging of biological samples, and a new fast algorithm is designed for computationally-efficient image reconstruction in this setting. Simulation and experimental results demonstrate that deconvolution can reduce the width of the point-spread function by at least 20%, and can significantly improve the contrast of high-resolution features. Temporally-resolved SLIM imaging with the high spatial resolution enabled by deconvolution provides new opportunities for studying the dynamics of cellular and sub-cellular processes.

  20. Automatic rocks detection and classification on high resolution images of planetary surfaces

    NASA Astrophysics Data System (ADS)

    Aboudan, A.; Pacifici, A.; Murana, A.; Cannarsa, F.; Ori, G. G.; Dell'Arciprete, I.; Allemand, P.; Grandjean, P.; Portigliotti, S.; Marcer, A.; Lorenzoni, L.

    2013-12-01

    High-resolution images can be used to obtain rocks location and size on planetary surfaces. In particular rock size-frequency distribution is a key parameter to evaluate the surface roughness, to investigate the geologic processes that formed the surface and to assess the hazards related with spacecraft landing. The manual search for rocks on high-resolution images (even for small areas) can be a very intensive work. An automatic or semi-automatic algorithm to identify rocks is mandatory to enable further processing as determining the rocks presence, size, height (by means of shadows) and spatial distribution over an area of interest. Accurate rocks and shadows contours localization are the key steps for rock detection. An approach to contour detection based on morphological operators and statistical thresholding is presented in this work. The identified contours are then fitted using a proper geometric model of the rocks or shadows and used to estimate salient rocks parameters (position, size, area, height). The performances of this approach have been evaluated both on images of Martian analogue area of Morocco desert and on HiRISE images. Results have been compared with ground truth obtained by means of manual rock mapping and proved the effectiveness of the algorithm. The rock abundance and rocks size-frequency distribution derived on selected HiRISE images have been compared with the results of similar analyses performed for the landing site certification of Mars landers (Viking, Pathfinder, MER, MSL) and with the available thermal data from IRTM and TES.

  1. High-Resolution In Vivo Imaging of Regimes of Laser Damage to the Primate Retina

    PubMed Central

    Pocock, Ginger M.; Oliver, Jeffrey W.; Specht, Charles S.; Estep, J. Scot; Noojin, Gary D.; Schuster, Kurt; Rockwell, Benjamin A.

    2014-01-01

    Purpose. To investigate fundamental mechanisms of regimes of laser induced damage to the retina and the morphological changes associated with the damage response. Methods. Varying grades of photothermal, photochemical, and photomechanical retinal laser damage were produced in eyes of eight cynomolgus monkeys. An adaptive optics confocal scanning laser ophthalmoscope and spectral domain optical coherence tomographer were combined to simultaneously collect complementary in vivo images of retinal laser damage during and following exposure. Baseline color fundus photography was performed to complement high-resolution imaging. Monkeys were perfused with 10% buffered formalin and eyes were enucleated for histological analysis. Results. Laser energies for visible retinal damage in this study were consistent with previously reported damage thresholds. Lesions were identified in OCT images that were not visible in direct ophthalmoscopic examination or fundus photos. Unique diagnostic characteristics, specific to each damage regime, were identified and associated with shape and localization of lesions to specific retinal layers. Previously undocumented retinal healing response to blue continuous wave laser exposure was recorded through a novel experimental methodology. Conclusion. This study revealed increased sensitivity of lesion detection and improved specificity to the laser of origin utilizing high-resolution imaging when compared to traditional ophthalmic imaging techniques in the retina. PMID:24891943

  2. High-resolution in vivo imaging of regimes of laser damage to the primate retina.

    PubMed

    Pocock, Ginger M; Oliver, Jeffrey W; Specht, Charles S; Estep, J Scot; Noojin, Gary D; Schuster, Kurt; Rockwell, Benjamin A

    2014-01-01

    Purpose. To investigate fundamental mechanisms of regimes of laser induced damage to the retina and the morphological changes associated with the damage response. Methods. Varying grades of photothermal, photochemical, and photomechanical retinal laser damage were produced in eyes of eight cynomolgus monkeys. An adaptive optics confocal scanning laser ophthalmoscope and spectral domain optical coherence tomographer were combined to simultaneously collect complementary in vivo images of retinal laser damage during and following exposure. Baseline color fundus photography was performed to complement high-resolution imaging. Monkeys were perfused with 10% buffered formalin and eyes were enucleated for histological analysis. Results. Laser energies for visible retinal damage in this study were consistent with previously reported damage thresholds. Lesions were identified in OCT images that were not visible in direct ophthalmoscopic examination or fundus photos. Unique diagnostic characteristics, specific to each damage regime, were identified and associated with shape and localization of lesions to specific retinal layers. Previously undocumented retinal healing response to blue continuous wave laser exposure was recorded through a novel experimental methodology. Conclusion. This study revealed increased sensitivity of lesion detection and improved specificity to the laser of origin utilizing high-resolution imaging when compared to traditional ophthalmic imaging techniques in the retina.

  3. High-resolution x-ray imaging using a structured scintillator

    SciTech Connect

    Hormozan, Yashar Sychugov, Ilya; Linnros, Jan

    2016-02-15

    Purpose: In this study, the authors introduce a new generation of finely structured scintillators with a very high spatial resolution (a few micrometers) compared to conventional scintillators, yet maintaining a thick absorbing layer for improved detectivity. Methods: Their concept is based on a 2D array of high aspect ratio pores which are fabricated by ICP etching, with spacings (pitches) of a few micrometers, on silicon and oxidation of the pore walls. The pores were subsequently filled by melting of powdered CsI(Tl), as the scintillating agent. In order to couple the secondary emitted photons of the back of the scintillator array to a CCD device, having a larger pixel size than the pore pitch, an open optical microscope with adjustable magnification was designed and implemented. By imaging a sharp edge, the authors were able to calculate the modulation transfer function (MTF) of this finely structured scintillator. Results: The x-ray images of individually resolved pores suggest that they have been almost uniformly filled, and the MTF measurements show the feasibility of a few microns spatial resolution imaging, as set by the scintillator pore size. Compared to existing techniques utilizing CsI needles as a structured scintillator, their results imply an almost sevenfold improvement in resolution. Finally, high resolution images, taken by their detector, are presented. Conclusions: The presented work successfully shows the functionality of their detector concept for high resolution imaging and further fabrication developments are most likely to result in higher quantum efficiencies.

  4. High-resolution x-ray imaging using a structured scintillator.

    PubMed

    Hormozan, Yashar; Sychugov, Ilya; Linnros, Jan

    2016-02-01

    In this study, the authors introduce a new generation of finely structured scintillators with a very high spatial resolution (a few micrometers) compared to conventional scintillators, yet maintaining a thick absorbing layer for improved detectivity. Their concept is based on a 2D array of high aspect ratio pores which are fabricated by ICP etching, with spacings (pitches) of a few micrometers, on silicon and oxidation of the pore walls. The pores were subsequently filled by melting of powdered CsI(Tl), as the scintillating agent. In order to couple the secondary emitted photons of the back of the scintillator array to a CCD device, having a larger pixel size than the pore pitch, an open optical microscope with adjustable magnification was designed and implemented. By imaging a sharp edge, the authors were able to calculate the modulation transfer function (MTF) of this finely structured scintillator. The x-ray images of individually resolved pores suggest that they have been almost uniformly filled, and the MTF measurements show the feasibility of a few microns spatial resolution imaging, as set by the scintillator pore size. Compared to existing techniques utilizing CsI needles as a structured scintillator, their results imply an almost sevenfold improvement in resolution. Finally, high resolution images, taken by their detector, are presented. The presented work successfully shows the functionality of their detector concept for high resolution imaging and further fabrication developments are most likely to result in higher quantum efficiencies.

  5. A Novel Image Compression Algorithm for High Resolution 3D Reconstruction

    NASA Astrophysics Data System (ADS)

    Siddeq, M. M.; Rodrigues, M. A.

    2014-06-01

    This research presents a novel algorithm to compress high-resolution images for accurate structured light 3D reconstruction. Structured light images contain a pattern of light and shadows projected on the surface of the object, which are captured by the sensor at very high resolutions. Our algorithm is concerned with compressing such images to a high degree with minimum loss without adversely affecting 3D reconstruction. The Compression Algorithm starts with a single level discrete wavelet transform (DWT) for decomposing an image into four sub-bands. The sub-band LL is transformed by DCT yielding a DC-matrix and an AC-matrix. The Minimize-Matrix-Size Algorithm is used to compress the AC-matrix while a DWT is applied again to the DC-matrix resulting in LL2, HL2, LH2 and HH2 sub-bands. The LL2 sub-band is transformed by DCT, while the Minimize-Matrix-Size Algorithm is applied to the other sub-bands. The proposed algorithm has been tested with images of different sizes within a 3D reconstruction scenario. The algorithm is demonstrated to be more effective than JPEG2000 and JPEG concerning higher compression rates with equivalent perceived quality and the ability to more accurately reconstruct the 3D models.

  6. Hierarchical graph-based segmentation for extracting road networks from high-resolution satellite images

    NASA Astrophysics Data System (ADS)

    Alshehhi, Rasha; Marpu, Prashanth Reddy

    2017-04-01

    Extraction of road networks in urban areas from remotely sensed imagery plays an important role in many urban applications (e.g. road navigation, geometric correction of urban remote sensing images, updating geographic information systems, etc.). It is normally difficult to accurately differentiate road from its background due to the complex geometry of the buildings and the acquisition geometry of the sensor. In this paper, we present a new method for extracting roads from high-resolution imagery based on hierarchical graph-based image segmentation. The proposed method consists of: 1. Extracting features (e.g., using Gabor and morphological filtering) to enhance the contrast between road and non-road pixels, 2. Graph-based segmentation consisting of (i) Constructing a graph representation of the image based on initial segmentation and (ii) Hierarchical merging and splitting of image segments based on color and shape features, and 3. Post-processing to remove irregularities in the extracted road segments. Experiments are conducted on three challenging datasets of high-resolution images to demonstrate the proposed method and compare with other similar approaches. The results demonstrate the validity and superior performance of the proposed method for road extraction in urban areas.

  7. High resolution in-vivo imaging of skin with full field optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Dalimier, E.; Bruhat, Alexis; Grieve, K.; Harms, F.; Martins, F.; Boccara, C.

    2014-03-01

    Full-field OCT (FFOCT) has the ability to provide en-face images with a very good axial sectioning as well as a very high transverse resolution (about 1 microns in all directions). Therefore it offers the possibility to visualize biological tissues with very high resolution both on the axial native view, and on vertical reconstructed sections. Here we investigated the potential dermatological applications of in-vivo skin imaging with FFOCT. A commercial FFOCT device was adapted for the in-vivo acquisition of stacks of images on the arm, hand and finger. Several subjects of different benign and pathological skin conditions were tested. The images allowed measurement of the stratum corneum and epidermis thicknesses, measurement of the stratum corneum refractive index, size measurement and count of the keratinocytes, visualization of the dermal-epidermal junction, and visualization of the melanin granules and of the melanocytes. Skins with different pigmentations could be discriminated and skin pathologies such as eczema could be identified. The very high resolution offered by FFOCT both on axial native images and vertical reconstructed sections allows for the visualization and measurement of a set of parameters useful for cosmetology and dermatology. In particular, FFOCT is a potential tool for the understanding and monitoring of skin hydration and pigmentation, as well as skin inflammation.

  8. Batch Co-Registration of Mars High-Resolution Images to HRSC MC11-E Mosaic

    NASA Astrophysics Data System (ADS)

    Sidiropoulos, Panagiotis; Muller, Jan-Peter

    2016-06-01

    Four NASA missions over the last forty years with onboard instruments for high-resolution orbital imaging have achieved both global coverage (with 6m CTX, 20m THEMIS-VIS and >8m Viking Orbiter cameras) as well as imaging with very high resolution in specific regions of interest (e.g. 25cm HiRISE and ≈1.5-12m MOC-NA cameras). Overall, this set of cameras have acquired more than 400,000 high-quality images of Mars with resolution between 25cm/pixel and 100m/pixel (Sidiropoulos and Muller, 2015). On the other hand, ESA has sent the only high-resolution stereo photogrammetric camera around Mars, HRSC onboard the Mars Express spacecraft, which has been mapping the Martian surface since 2004 with a resolution of 12.5 m/pixel (Jaumann et al., 2015). Initially the raw images are combined through an elaborate photogrammetric process to get (single-strip) 3D products (i.e. digital terrain models (DTMs) and derived orthorectified images (ORIs)). However, recently the processing chain has changed, and the single-strip product release was temporarily halted to be replaced by the production and release of mosaics of Mars quadrangles. The first product of this kind is the mosaic for the East part of quadrangle MC11 (i.e. the MC11-E mosaic), a product with 12.5 metres per pixel resolution in the panchromatic image and 50 metres per pixel resolution in the corresponding DTM (Gwinner et al., 2015). Such a product provides an excellent basemap to co-register and orthorectify all NASA high-resolution (≤100m/pixel) orbital images. The need for this co-registration to HRSC comes from their poor areo-referencing, which often leads to large deviations (reaching up to several kilometres) between the area they are supposed to image and the area they are actually imaging. After co-registration, all products are projected onto an common 3D coordinate system, which allows an examination of dynamic features of Mars through the changes that happen on its surface. In this work, we present the

  9. Vehicle extraction from high-resolution satellite image using template matching

    NASA Astrophysics Data System (ADS)

    Natt, Dehchaiwong; Cao, Xiaoguang

    2015-12-01

    The process of vehicle examination by using satellite images is complicated and cumbersome process. At the present, the high definition satellite images are being used, however, the images of the vehicles can be seen as just a small point which is difficult to separate it out from the background that the image details are not sufficient to identify small objects. In this research, the techniques for the process of vehicle examination by using satellite images were applied by using image data from Pléiades which is the satellite image with high resolution of 0.40 m. The objective of this research is to study and develop the device for data extracting from satellite images, and the received data would be organized and created as Geospatial information by the concept of the picture matching with a pattern matching or Template Matching developed with Matlab program and Sum of Absolute Difference method collaborated with Neural Network technique in order to help evaluating pattern matching between template images of cars and cars' images which were used to examine from satellite images. The result obtained from the comparison with template data shows that data extraction accuracy is greater than 90%, and the extracted data can be imported into Geospatial information database. Moreover, the data can be displayed in Geospatial information Software, and it also can be searched by quantity condition and satellite image position.

  10. Rapid Diagnosis of Tuberculosis by Real-Time High-Resolution Imaging of Mycobacterium tuberculosis Colonies.

    PubMed

    Ghodbane, Ramzi; Asmar, Shady; Betzner, Marlena; Linet, Marie; Pierquin, Joseph; Raoult, Didier; Drancourt, Michel

    2015-08-01

    Culture remains the cornerstone of diagnosis for pulmonary tuberculosis, but the fastidiousness of Mycobacterium tuberculosis may delay culture-based diagnosis for weeks. We evaluated the performance of real-time high-resolution imaging for the rapid detection of M. tuberculosis colonies growing on a solid medium. A total of 50 clinical specimens, including 42 sputum specimens, 4 stool specimens, 2 bronchoalveolar lavage fluid specimens, and 2 bronchial aspirate fluid specimens were prospectively inoculated into (i) a commercially available Middlebrook broth and evaluated for mycobacterial growth indirectly detected by measuring oxygen consumption (standard protocol) and (ii) a home-made solid medium incubated in an incubator featuring real-time high-resolution imaging of colonies (real-time protocol). Isolates were identified by Ziehl-Neelsen staining and matrix-assisted laser desorption ionization-time of flight mass spectrometry. Use of the standard protocol yielded 14/50 (28%) M. tuberculosis isolates, which is not significantly different from the 13/50 (26%) M. tuberculosis isolates found using the real-time protocol (P = 1.00 by Fisher's exact test), and the contamination rate of 1/50 (2%) was not significantly different from the contamination rate of 2/50 (4%) using the real-time protocol (P = 1.00). The real-time imaging protocol showed a 4.4-fold reduction in time to detection, 82 ± 54 h versus 360 ± 142 h (P < 0.05). These preliminary data give the proof of concept that real-time high-resolution imaging of M. tuberculosis colonies is a new technology that shortens the time to growth detection and the laboratory diagnosis of pulmonary tuberculosis.

  11. High-Resolution Seismic Imaging of Quaternary Faults and Deformation in the Los Angeles Region

    NASA Astrophysics Data System (ADS)

    Stephenson, W. J.; Odum, J. K.; Williams, R. A.; Pratt, T. L.; Dolan, J.; Shaw, J. H.

    2001-12-01

    We present results from several P-wave high-resolution seismic imaging studies in the Los Angeles region that characterize Quaternary fault activity and associated deformation. From high-resolution seismic reflection data, we seek crucial information on shallow basin geometry as well as near-surface fault geometry, displacement, slip rates, and timing of Quaternary deformation. Data acquired along a profile in Sherman Oaks reveal a geologic structure in the upper 600 m that contributed to the increased earthquake ground shaking in the high-damage areas south of and along the Los Angeles River resulting from the 1994 Northridge earthquake. A shallow sub-basin imaged on the Sherman Oaks line correlates with an area that experienced greater earthquake damage from possible geometric focussing effects. Finite-difference modeling of the imaged structural geometry along the profile suggests that a peak horizontal-velocity amplification factor of two-and-greater, as well as spatial variability, can be explained in the high-damage area by the sub-basin. High-resolution seismic reflection data acquired across the Santa Monica fault confirm the location of the fault and link related shallow strike-slip faults seen in a nearby trench to deeper structures previously observed in regional studies. The high-resolution seismic data image deformation as shallow as 15 m depth and show the Santa Monica fault dips about 30 degrees north in the upper 300 m. These data, combined with soil age estimates from the trench, yield a reverse-slip rate for the fault of about 0.5 mm/yr. The Puente Hills thrust fault is one of the major faults underlying the urban Los Angeles Basin. Industry-scale and high-resolution seismic reflection images define the location and geometry of active folds above the Puente Hills thrust fault. Four seismic profiles acquired at two locations delineate fold geometry above the thrust. At one of these sites we image an active synclinal axial surface with strata

  12. High-resolution ultrasound imaging and noninvasive optoacoustic monitoring of blood variables in peripheral blood vessels

    NASA Astrophysics Data System (ADS)

    Petrov, Irene Y.; Petrov, Yuriy; Prough, Donald S.; Esenaliev, Rinat O.

    2011-03-01

    Ultrasound imaging is being widely used in clinics to obtain diagnostic information non-invasively and in real time. A high-resolution ultrasound imaging platform, Vevo (VisualSonics, Inc.) provides in vivo, real-time images with exceptional resolution (up to 30 microns) using high-frequency transducers (up to 80 MHz). Recently, we built optoacoustic systems for probing radial artery and peripheral veins that can be used for noninvasive monitoring of total hemoglobin concentration, oxyhemoglobin saturation, and concentration of important endogenous and exogenous chromophores (such as ICG). In this work we used the high-resolution ultrasound imaging system Vevo 770 for visualization of the radial artery and peripheral veins and acquired corresponding optoacoustic signals from them using the optoacoustic systems. Analysis of the optoacoustic data with a specially developed algorithm allowed for measurement of blood oxygenation in the blood vessels as well as for continuous, real-time monitoring of arterial and venous blood oxygenation. Our results indicate that: 1) the optoacoustic technique (unlike pure optical approaches and other noninvasive techniques) is capable of accurate peripheral venous oxygenation measurement; and 2) peripheral venous oxygenation is dependent on skin temperature and local hemodynamics. Moreover, we performed for the first time (to the best of our knowledge) a comparative study of optoacoustic arterial oximetry and a standard pulse oximeter in humans and demonstrated superior performance of the optoacoustic arterial oximeter, in particular at low blood flow.

  13. High-resolution imaging and nano-manipulation of biological structures on surface.

    PubMed

    Zhang, Yi; Hu, Xiaofang; Sun, Jielin; Shen, Yi; Hu, Jun; Xu, Xuemin; Shao, Zhifeng

    2011-07-01

    In this mini-review we discuss our recent findings on imaging and manipulation of biological macromolecular structures by atomic force microscopy (AFM). In the first part of this review, we focus on high-resolution imaging of selected biological samples. AFM images of membrane proteins have revealed detailed conformational features related to identifiable biological functions. Different self-assembling behaviors of short peptides into supramolecular structures on various substrates under controlled environmental conditions have been systematically studied with AFM imaging. In the second part, we present a novel nano-manipulation technique for manipulating, isolating, amplifying, and sequencing of individual DNA molecules, which may find unique applications in the analysis of difficult sequence structures. Finally, we discuss how to characterize the elasticity of individual biomolecules and live cells. These results demonstrate that not only the high resolution capacity of the AFM is suited to resolve certain biological questions, but can also be applied to single molecule isolation and biomechanical analysis with its unique advantages. Copyright © 2010 Wiley-Liss, Inc.

  14. MTRC compensation in high-resolution ISAR imaging via improved polar format algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Li, Hao; Li, Na; Xu, Shiyou; Chen, Zengping

    2014-10-01

    Migration through resolution cells (MTRC) is generated in high-resolution inverse synthetic aperture radar (ISAR) imaging. A MTRC compensation algorithm for high-resolution ISAR imaging based on improved polar format algorithm (PFA) is proposed in this paper. Firstly, in the situation that a rigid-body target stably flies, the initial value of the rotation angle and center of the target is obtained from the rotation of radar line of sight (RLOS) and high range resolution profile (HRRP). Then, the PFA is iteratively applied to the echo data to search the optimization solution based on minimum entropy criterion. The procedure starts with the estimated initial rotation angle and center, and terminated when the entropy of the compensated ISAR image is minimized. To reduce the computational load, the 2-D iterative search is divided into two 1-D search. One is carried along the rotation angle and the other one is carried along rotation center. Each of the 1-D searches is realized by using of the golden section search method. The accurate rotation angle and center can be obtained when the iterative search terminates. Finally, apply the PFA to compensate the MTRC by the use of the obtained optimized rotation angle and center. After MTRC compensation, the ISAR image can be best focused. Simulated and real data demonstrate the effectiveness and robustness of the proposed algorithm.

  15. Spmk and Grabcut Based Target Extraction from High Resolution Remote Sensing Images

    NASA Astrophysics Data System (ADS)

    Cui, Weihong; Wang, Guofeng; Feng, Chenyi; Zheng, Yiwei; Li, Jonathan; Zhang, Yi

    2016-06-01

    Target detection and extraction from high resolution remote sensing images is a basic and wide needed application. In this paper, to improve the efficiency of image interpretation, we propose a detection and segmentation combined method to realize semi-automatic target extraction. We introduce the dense transform color scale invariant feature transform (TC-SIFT) descriptor and the histogram of oriented gradients (HOG) & HSV descriptor to characterize the spatial structure and color information of the targets. With the k-means cluster method, we get the bag of visual words, and then, we adopt three levels' spatial pyramid (SP) to represent the target patch. After gathering lots of different kinds of target image patches from many high resolution UAV images, and using the TC-SIFT-SP and the multi-scale HOG & HSV feature, we constructed the SVM classifier to detect the target. In this paper, we take buildings as the targets. Experiment results show that the target detection accuracy of buildings can reach to above 90%. Based on the detection results which are a series of rectangle regions of the targets. We select the rectangle regions as candidates for foreground and adopt the GrabCut based and boundary regularized semi-auto interactive segmentation algorithm to get the accurate boundary of the target. Experiment results show its accuracy and efficiency. It can be an effective way for some special targets extraction.

  16. A flexible and accurate digital volume correlation method applicable to high-resolution volumetric images

    NASA Astrophysics Data System (ADS)

    Pan, Bing; Wang, Bo

    2017-10-01

    Digital volume correlation (DVC) is a powerful technique for quantifying interior deformation within solid opaque materials and biological tissues. In the last two decades, great efforts have been made to improve the accuracy and efficiency of the DVC algorithm. However, there is still a lack of a flexible, robust and accurate version that can be efficiently implemented in personal computers with limited RAM. This paper proposes an advanced DVC method that can realize accurate full-field internal deformation measurement applicable to high-resolution volume images with up to billions of voxels. Specifically, a novel layer-wise reliability-guided displacement tracking strategy combined with dynamic data management is presented to guide the DVC computation from slice to slice. The displacements at specified calculation points in each layer are computed using the advanced 3D inverse-compositional Gauss–Newton algorithm with the complete initial guess of the deformation vector accurately predicted from the computed calculation points. Since only limited slices of interest in the reference and deformed volume images rather than the whole volume images are required, the DVC calculation can thus be efficiently implemented on personal computers. The flexibility, accuracy and efficiency of the presented DVC approach are demonstrated by analyzing computer-simulated and experimentally obtained high-resolution volume images.

  17. In-vivo high resolution corneal imaging and analysis on animal models for clinical applications

    NASA Astrophysics Data System (ADS)

    Hong, Jesmond; Shinoj, V. K.; Murukeshan, V. M.; Baskaran, M.; Aung, Tin

    2015-07-01

    A simple and low cost optical probe system for the high resolution imaging of the cornea is proposed, based on a Gaussian beam epi-illumination configuration. Corneal topography is obtained by moving the scanning spot across the eye in a raster fashion whereas pachymetry data is achieved by reconstructing the images obtained at different depths. The proposed prototype has been successfully tested on porcine eye samples ex vivo and subsequently on laboratory animals, such as the New Zealand White Rabbit, in vivo. This proposed system and methodology pave the way for realizing a simple and inexpensive optical configuration for pachymetry and keratometry readings, with achievable resolution up to the cellular level. This novel and non-contact high resolution imaging modality demonstrates high intraobserver reproducibility and repeatability. Together with its sophisticated data analysis strategies and safety profile, it is believed to complement existing imaging modalities in the assessment and evaluation of corneal diseases, which enable a decrease in morbidity and improvement in the effectiveness of subsequent treatment.

  18. Detection of sub-kilometer craters in high resolution planetary images using shape and texture features

    NASA Astrophysics Data System (ADS)

    Bandeira, Lourenço; Ding, Wei; Stepinski, Tomasz F.

    2012-01-01

    Counting craters is a paramount tool of planetary analysis because it provides relative dating of planetary surfaces. Dating surfaces with high spatial resolution requires counting a very large number of small, sub-kilometer size craters. Exhaustive manual surveys of such craters over extensive regions are impractical, sparking interest in designing crater detection algorithms (CDAs). As a part of our effort to design a CDA, which is robust and practical for planetary research analysis, we propose a crater detection approach that utilizes both shape and texture features to identify efficiently sub-kilometer craters in high resolution panchromatic images. First, a mathematical morphology-based shape analysis is used to identify regions in an image that may contain craters; only those regions - crater candidates - are the subject of further processing. Second, image texture features in combination with the boosting ensemble supervised learning algorithm are used to accurately classify previously identified candidates into craters and non-craters. The design of the proposed CDA is described and its performance is evaluated using a high resolution image of Mars for which sub-kilometer craters have been manually identified. The overall detection rate of the proposed CDA is 81%, the branching factor is 0.14, and the overall quality factor is 72%. This performance is a significant improvement over the previous CDA based exclusively on the shape features. The combination of performance level and computational efficiency offered by this CDA makes it attractive for practical application.

  19. Damaged road extracting with high-resolution aerial image of post-earthquake

    NASA Astrophysics Data System (ADS)

    Zheng, Zezhong; Pu, Chengjun; Zhu, Mingcang; Xia, Jun; Zhang, Xiang; Liu, Yalan; Li, Jiang

    2015-12-01

    With the rapid development of earth observation technology, remote sensing images have played more important roles, because the high resolution images can provide the original data for object recognition, disaster investigation, and so on. When a disastrous earthquake breaks out, a large number of roads could be damaged instantly. There are a lot of approaches about road extraction, such as region growing, gray threshold, and k-means clustering algorithm. We could not obtain the undamaged roads with these approaches, if the trees or their shadows along the roads are difficult to be distinguished from the damaged road. In the paper, a method is presented to extract the damaged road with high resolution aerial image of post-earthquake. Our job is to extract the damaged road and the undamaged with the aerial image. We utilized the mathematical morphology approach and the k-means clustering algorithm to extract the road. Our method was composed of four ingredients. Firstly, the mathematical morphology filter operators were employed to remove the interferences from the trees or their shadows. Secondly, the k-means algorithm was employed to derive the damaged segments. Thirdly, the mathematical morphology approach was used to extract the undamaged road; Finally, we could derive the damaged segments by overlaying the road networks of pre-earthquake. Our results showed that the earthquake, broken in Yaan, was disastrous for the road, Therefore, we could take more measures to keep it clear.

  20. A pilot evaluation study of high resolution digital thermal imaging in the assessment of burn depth.

    PubMed

    Hardwicke, Joseph; Thomson, Richard; Bamford, Amy; Moiemen, Naiem

    2013-02-01

    Thermal imaging is a tool that can be used to determine burn depth. We have revisited the use of this technology in the assessment of burns and aim to establish if high resolution, real-time technology can be practically used in conjunction with clinical examination to determine burn depth. 11 patients with burns affecting upper and lower limbs and the anterior and posterior trunk were included in this study. Digital and thermal images were recorded at between 42 h and 5 days post burn. When compared to skin temperature, full thickness burns were significantly cooler (p<0.001), as were deep partial thickness burns (p<0.05). Superficial partial thickness burns were not significantly different in temperature than non-burnt skin (p>0.05). Typically, full thickness burns were 2.3°C cooler than non-burnt skin; deep partial thickness burns were 1.2°C cooler than non-burnt skin; whilst superficial burns were only 0.1°C cooler. Thermal imaging can correctly determine difference in burn depth. The thermal camera produces images of high resolution and is quick and easy to use. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

  1. [Imaging of the lumbosacral plexus : Diagnostics and treatment planning with high-resolution procedures].

    PubMed

    Jengojan, S; Schellen, C; Bodner, G; Kasprian, G

    2017-03-01

    Technical advances in magnetic resonance (MR) and ultrasound-based neurography nowadays facilitate the radiological assessment of the lumbosacral plexus. Anatomy and imaging of the lumbosacral plexus and diagnostics of the most common pathologies. Description of the clinically feasible combination of magnetic resonance imaging (MRI) and ultrasound diagnostics, case-based illustration of imaging techniques and individual advantages of MRI and ultrasound-based diagnostics for various pathologies of the lumbosacral plexus and its peripheral nerves. High-resolution ultrasound-based neurography (HRUS) is particularly valuable for the assessment of superficial structures of the lumbosacral plexus. Depending on the examiner's experience, anatomical variations of the sciatic nerve (e. g. relevant in piriformis syndrome) as well as more subtle variations, for example as seen in neuritis, can be sonographically depicted and assessed. The use of MRI enables the diagnostic evaluation of more deeply located nerve structures, such as the pudendal and the femoral nerves. Modern MRI techniques, such as peripheral nerve tractography allow three-dimensional depiction of the spatial relationship between nerves and local tumors or traumatic alterations. This can be beneficial for further therapy planning. The anatomy and pathology of the lumbosacral plexus can be reliably imaged by the meaningful combination of MRI and ultrasound-based high resolution neurography.

  2. Time-Optimized High-Resolution Readout-Segmented Diffusion Tensor Imaging

    PubMed Central

    Reishofer, Gernot; Koschutnig, Karl; Langkammer, Christian; Porter, David; Jehna, Margit; Enzinger, Christian; Keeling, Stephen; Ebner, Franz

    2013-01-01

    Readout-segmented echo planar imaging with 2D navigator-based reacquisition is an uprising technique enabling the sampling of high-resolution diffusion images with reduced susceptibility artifacts. However, low signal from the small voxels and long scan times hamper the clinical applicability. Therefore, we introduce a regularization algorithm based on total variation that is applied directly on the entire diffusion tensor. The spatially varying regularization parameter is determined automatically dependent on spatial variations in signal-to-noise ratio thus, avoiding over- or under-regularization. Information about the noise distribution in the diffusion tensor is extracted from the diffusion weighted images by means of complex independent component analysis. Moreover, the combination of those features enables processing of the diffusion data absolutely user independent. Tractography from in vivo data and from a software phantom demonstrate the advantage of the spatially varying regularization compared to un-regularized data with respect to parameters relevant for fiber-tracking such as Mean Fiber Length, Track Count, Volume and Voxel Count. Specifically, for in vivo data findings suggest that tractography results from the regularized diffusion tensor based on one measurement (16 min) generates results comparable to the un-regularized data with three averages (48 min). This significant reduction in scan time renders high resolution (1×1×2.5 mm3) diffusion tensor imaging of the entire brain applicable in a clinical context. PMID:24019951

  3. 3.0 T high-resolution MR imaging of carpal ligaments and TFCC.

    PubMed

    Lenk, S; Ludescher, B; Martirosan, P; Schick, F; Claussen, C D; Schlemmer, H-P

    2004-05-01

    To determine the diagnostic value of 3.0 Tesla MRI for imaging carpal ligaments and triangular fibrocartilage complex (TFCC). Image quality of different optimized MRI sequences is evaluated for high resolution wrist anatomy. Ten healthy volunteers were examined at 3.0 T and 1.5 T using following sequences: T1 SE, fat-saturated PD-/T2-TSE, TIRM, 3D T1/T2* DESS, 3D-CISS, 2D and 3D T2* MEDIC. Voxel size varied from 0.2 x 0.2 x 1.5 mm (2D sequences) to 0.33 mm (3) and 0.26 mm (3) (3D sequences). Image quality (signal-to-noise-ratio, contrast-to-noise-ratio, artifacts) and carpal ligament/TFCC detection rate were judged by a score. The results obtained from the 3.0 T and 1.5 T devices were compared. With identical voxel size, image matrix and FOV, 3.0 T MRI provided significantly better image quality and ligament detection rates for all sequences in comparison with 1.5 T. The 2D and 3D MEDIC sequences yielded best image quality and detection rates. Excellent image quality and visualization of ligament structures by the fat-suppressed PD-TSE sequence were compromised by a relatively high susceptibility to pulsation and motion artifacts. T1 SE and 3D DESS sequences gave moderate image quality and allowed only partial differentiation between ligament structures. TIRM, T2-TSE and 3D-CISS sequence proved to be unsuitable for examining ligaments at 3.0 T due to their poor image quality and detection rate. 3.0 T MRI of the wrist proved to be superior to 1.5 T MRI for high-resolution imaging of carpal ligaments and TFCC using 2D and 3D T2* MEDIC sequences. Clinical studies investigating ligament injuries or carpal instability are recommended for evaluating clinical relevance of high-resolution MRI of the wrist.

  4. IMAGE-WARP: a real-space restoration method for high-resolution STEM images using quantitative HRTEM analysis.

    PubMed

    Recnik, Aleksander; Möbus, Günter; Sturm, Saso

    2005-07-01

    We have developed a new method for processing distorted high-resolution scanning transmission electron microscopy (STEM) images. The method is based on finding the displaced vertices in the experimental STEM image and warping to geometrically correct reference grid of the object. As a reference grid for warping a structural model obtained using a high-resolution transmission electron microscopy (HRTEM) analysis of the area of interest is utilised. Combined with quantitative HRTEM analysis the IMAGE-WARP method provides a real-space restoration of high-resolution high-angle annular dark-field (HAADF) STEM images without affecting the original Z-contrast information. The method can be applied to extract valuable compositional atomic-column data from any HAADF-STEM image of any kind of bulk crystals with local occupancy or chemistry fluctuations, stacking faults, special grain boundaries or interfaces, for which we have an available structural model. After the warping, distortion-corrected images can be further enhanced using conventional image-filtering techniques, and finally quantified with HAADF-STEM image simulations. The applicability of the IMAGE-WARP method was illustrated using experimental HAADF-STEM images of a strontium titanate crystal disrupted with a Ruddlesden-Popper-type antiphase boundary.

  5. Automatic Detection of Changes on Mars Surface from High-Resolution Orbital Images

    NASA Astrophysics Data System (ADS)

    Sidiropoulos, Panagiotis; Muller, Jan-Peter

    2017-04-01

    Over the last 40 years Mars has been extensively mapped by several NASA and ESA orbital missions, generating a large image dataset comprised of approximately 500,000 high-resolution images (of <100m resolution). The overall area mapped from orbital imagery is approximately 6 times the overall surface of Mars [1]. The multi-temporal coverage of Martian surface allows a visual inspection of the surface to identify dynamic phenomena, i.e. surface features that change over time, such as slope streaks [2], recurring slope lineae [3], new impact craters [4], etc. However, visual inspection for change detection is a limited approach, since it requires extensive use of human resources, which is very difficult to achieve when dealing with a rapidly increasing volume of data. Although citizen science can be employed for training and verification it is unsuitable for planetwide systematic change detection. In this work, we introduce a novel approach in planetary image change detection, which involves a batch-mode automatic change detection pipeline that identifies regions that have changed. This is tested in anger, on tens of thousands of high-resolution images over the MC11 quadrangle [5], acquired by CTX, HRSC, THEMIS-VIS and MOC-NA instruments [1]. We will present results which indicate a substantial level of activity in this region of Mars, including instances of dynamic natural phenomena that haven't been cataloged in the planetary science literature before. We will demonstrate the potential and usefulness of such an automatic approach in planetary science change detection. Acknowledgments: The research leading to these results has received funding from the STFC "MSSL Consolidated Grant" ST/K000977/1 and partial support from the European Union's Seventh Framework Programme (FP7/2007-2013) under iMars grant agreement n° 607379. References: [1] P. Sidiropoulos and J. - P. Muller (2015) On the status of orbital high-resolution repeat imaging of Mars for the observation of

  6. Multiparametric high-resolution imaging of native proteins by force-distance curve-based AFM.

    PubMed

    Pfreundschuh, Moritz; Martinez-Martin, David; Mulvihill, Estefania; Wegmann, Susanne; Muller, Daniel J

    2014-05-01

    A current challenge in the life sciences is to understand how the properties of individual molecular machines adjust in order to meet the functional requirements of the cell. Recent developments in force-distance (FD) curve-based atomic force microscopy (FD-based AFM) enable researchers to combine sub-nanometer imaging with quantitative mapping of physical, chemical and biological properties. Here we present a protocol to apply FD-based AFM to the multiparametric imaging of native proteins under physiological conditions. We describe procedures for experimental FD-based AFM setup, high-resolution imaging of proteins in the native unperturbed state with simultaneous quantitative mapping of multiple parameters, and data interpretation and analysis. The protocol, which can be completed in 1-3 d, enables researchers to image proteins and protein complexes in the native unperturbed state and to simultaneously map their biophysical and biochemical properties at sub-nanometer resolution.

  7. Investigation of non-linear imaging in high-resolution transmission electron microscopy.

    PubMed

    Chang, Yunjie; Wang, Yumei; Cui, Yanxiang; Ge, Binghui

    2016-12-01

    Transmission cross-coefficient theory and pseudo-weak-phase object approximation theory were combined to investigate the non-linear imaging in high-resolution transmission electron microscopy (HRTEM). The analytical expressions of linear and non-linear imaging components in diffractogram were obtained and changes of linear and non-linear components over sample thickness were analyzed. Moreover, the linear and non-linear components are found to be an odd and even-function of the defocus and Cs, respectively. Based on this, a method for separating the linear and non-linear contrasts in Cs-corrected (non-zero Cs conditions included) HRTEM images was proposed, and its effectiveness was confirmed by image simulations with AlN as an example.

  8. High resolution photoacoustic imaging of microvasculature in normal and cancerous bladders

    NASA Astrophysics Data System (ADS)

    Xie, Zhixing; Roberts, William; Carson, Paul L.; Liu, Xiaojun; Tao, Chao; Wang, Xueding

    2013-03-01

    We explored the potential of an emerging laser-based technology, photoacoustic imaging (PAI), for bladder cancer diagnosis through high resolution imaging of microvasculature in the interior bladder tissues. Images of ex vivo canine bladders demonstrated the excellent ability of PAI to map three-dimensional microvasculature in optically scattering bladder tissues. By comparing the results from human bladder specimens affected by cancer to those from the normal control, the feasibility of PAI in differentiating malignant from benign bladder tissues was explored. The reported distinctive morphometric characteristics of tumor microvasculature can be seen in the images from cancer samples, suggesting that PAI may allow in vivo assessment of neoangiogenesis that is closely associated with bladder cancer generation and progression. By presenting subsurface morphological and physiological information in bladder tissues, PAI, when performed in a similar way to that in conventional endoscopy, provides an opportunity for improved diagnosis, staging and treatment guidance of bladder cancer.

  9. Photodissociation of ozone at 276nm by photofragment imaging and high resolution photofragment translational spectroscopy

    SciTech Connect

    Blunt, D.A.; Suits, A.G.

    1996-11-01

    The photodissociation of ozone at 276 nm is investigated using both state resolved ion imaging and high-resolution photofragment translational spectroscopy. Ion images from both [3+1] and [2+1] resonance enhanced multiphoton ionization of the O({sup 1}D) photofragment are reported. All images show strong evidence of O({sup 1}D) orbital alignment. Photofragment translation spectroscopy time-of-flight spectra are reported for the O{sub 2} ({sup 1}{Delta}{sub g}) photofragment. Total kinetic energy release distributions determined form these spectra are generally consistent with those distributions determined from imaging data. Observed angular distributions are reported for both detection methods, pointing to some unresolved questions for ozone dissociation in this wavelength region.

  10. High-Resolution Dynamic Speech Imaging with Joint Low-Rank and Sparsity Constraints

    PubMed Central

    Fu, Maojing; Zhao, Bo; Carignan, Christopher; Shosted, Ryan K.; Perry, Jamie L.; Kuehn, David P.; Liang, Zhi-Pei; Sutton, Bradley P.

    2014-01-01

    Purpose To enable dynamic speech imaging with high spatiotemporal resolution and full-vocal-tract spatial coverage, leveraging recent advances in sparse sampling. Methods An imaging method is developed to enable high-speed dynamic speech imaging exploiting low-rank and sparsity of the dynamic images of articulatory motion during speech. The proposed method includes: a) a novel data acquisition strategy that collects navigators with high temporal frame rate, and b) an image reconstruction method that derives temporal subspaces from navigators and reconstructs high-resolution images from sparsely sampled data with joint low-rank and sparsity constraints. Results The proposed method has been systematically evaluated and validated through several dynamic speech experiments. A nominal imaging speed of 102 frames per second (fps) was achieved for a single-slice imaging protocol with a spatial resolution of 2.2 × 2.2 × 6.5 mm3. An eight-slice imaging protocol covering the entire vocal tract achieved a nominal imaging speed of 12.8 fps with the identical spatial resolution. The effectiveness of the proposed method and its practical utility was also demonstrated in a phonetic investigation. Conclusion High spatiotemporal resolution with full-vocal-tract spatial coverage can be achieved for dynamic speech imaging experiments with low-rank and sparsity constraints. PMID:24912452

  11. Scatter reduction for high resolution image detectors with a region of interest attenuator

    NASA Astrophysics Data System (ADS)

    Jain, Amit; Bednarek, Daniel R.; Rudin, Stephen

    2014-03-01

    Compton scatter is the main interaction of x-rays with objects undergoing radiographic and fluoroscopic imaging procedures. Such scatter is responsible for reducing image signal to noise ratio which can negatively impact object detection especially for low contrast objects. To reduce scatter, possible methods are smaller fields-of-view, larger air gaps and the use of an anti-scatter grid. Smaller fields of view may not be acceptable and scanned-beam radiography is not practical for real-time imaging. Air gaps can increase geometric unsharpness and thus degrade image resolution. Deployment of an anti-scatter grid is not well suited for high resolution imagers due to the unavailability of high line density grids needed to prevent grid-line artifacts. However, region of interest (ROI) imaging can be used not only for dose reduction but also for scatter reduction in the ROI. The ROI region receives unattenuated x-rays while the peripheral region receives x-rays reduced in intensity by an ROI attenuator. The scatter within the ROI part of the image originates from both the unattenuated ROI and the attenuated peripheral region. The scatter contribution from the periphery is reduced in intensity because of the reduced primary x-rays in that region and the scatter fraction in the ROI is thus reduced. In this study, the scatter fraction for various kVp's, air-gaps and field sizes was measured for a uniform head equivalent phantom. The scatter fraction in the ROI was calculated using a derived scatter fraction formula, which was validated with experimental measurements. It is shown that use of a ROI attenuator can be an effective way to reduce both scatter and patient dose while maintaining the superior image quality of high resolution detectors.

  12. Scatter reduction for high resolution image detectors with a region of interest attenuator

    PubMed Central

    Jain, Amit; Bednarek, Daniel R.; Rudin, Stephen

    2014-01-01

    Compton scatter is the main interaction of x-rays with objects undergoing radiographic and fluoroscopic imaging procedures. Such scatter is responsible for reducing image signal to noise ratio which can negatively impact object detection especially for low contrast objects. To reduce scatter, possible methods are smaller fields-of-view, larger air gaps and the use of an anti-scatter grid. Smaller fields of view may not be acceptable and scanned-beam radiography is not practical for real-time imaging. Air gaps can increase geometric unsharpness and thus degrade image resolution. Deployment of an anti-scatter grid is not well suited for high resolution imagers due to the unavailability of high line density grids needed to prevent grid-line artifacts. However, region of interest (ROI) imaging can be used not only for dose reduction but also for scatter reduction in the ROI. The ROI region receives unattenuated x-rays while the peripheral region receives x-rays reduced in intensity by an ROI attenuator. The scatter within the ROI part of the image originates from both the unattenuated ROI and the attenuated peripheral region. The scatter contribution from the periphery is reduced in intensity because of the reduced primary x-rays in that region and the scatter fraction in the ROI is thus reduced. In this study, the scatter fraction for various kVp’s, air-gaps and field sizes was measured for a uniform head equivalent phantom. The scatter fraction in the ROI was calculated using a derived scatter fraction formula, which was validated with experimental measurements. It is shown that use of a ROI attenuator can be an effective way to reduce both scatter and patient dose while maintaining the superior image quality of high resolution detectors. PMID:25302000

  13. Workflow for the use of a high-resolution image detector in endovascular interventional procedures

    NASA Astrophysics Data System (ADS)

    Rana, R.; Loughran, B.; Swetadri Vasan, S. N.; Pope, L.; Ionita, C. N.; Siddiqui, A.; Lin, N.; Bednarek, D. R.; Rudin, S.

    2014-03-01

    Endovascular image-guided intervention (EIGI) has become the primary interventional therapy for the most widespread vascular diseases. These procedures involve the insertion of a catheter into the femoral artery, which is then threaded under fluoroscopic guidance to the site of the pathology to be treated. Flat Panel Detectors (FPDs) are normally used for EIGIs; however, once the catheter is guided to the pathological site, high-resolution imaging capabilities can be used for accurately guiding a successful endovascular treatment. The Micro-Angiographic Fluoroscope (MAF) detector provides needed high-resolution, high-sensitivity, and real-time imaging capabilities. An experimental MAF enabled with a Control, Acquisition, Processing, Image Display and Storage (CAPIDS) system was installed and aligned on a detector changer attached to the C-arm of a clinical angiographic unit. The CAPIDS system was developed and implemented using LabVIEW software and provides a user-friendly interface that enables control of several clinical radiographic imaging modes of the MAF including: fluoroscopy, roadmap, radiography, and digital-subtraction-angiography (DSA). Using the automatic controls, the MAF detector can be moved to the deployed position, in front of a standard FPD, whenever higher resolution is needed during angiographic or interventional vascular imaging procedures. To minimize any possible negative impact to image guidance with the two detector systems, it is essential to have a well-designed workflow that enables smooth deployment of the MAF at critical stages of clinical procedures. For the ultimate success of this new imaging capability, a clear understanding of the workflow design is essential. This presentation provides a detailed description and demonstration of such a workflow design.

  14. Workflow for the use of a high-resolution image detector in endovascular interventional procedures

    PubMed Central

    Rana, R.; Loughran, B.; Swetadri Vasan, S. N.; Pope, L.; Ionita, C. N.; Siddiqui, A.; Lin, N.; Bednarek, D. R.; Rudin, S.

    2014-01-01

    Endovascular image-guided intervention (EIGI) has become the primary interventional therapy for the most widespread vascular diseases. These procedures involve the insertion of a catheter into the femoral artery, which is then threaded under fluoroscopic guidance to the site of the pathology to be treated. Flat Panel Detectors (FPDs) are normally used for EIGIs; however, once the catheter is guided to the pathological site, high-resolution imaging capabilities can be used for accurately guiding a successful endovascular treatment. The Micro-Angiographic Fluoroscope (MAF) detector provides needed high-resolution, high-sensitivity, and real-time imaging capabilities. An experimental MAF enabled with a Control, Acquisition, Processing, Image Display and Storage (CAPIDS) system was installed and aligned on a detector changer attached to the C-arm of a clinical angiographic unit. The CAPIDS system was developed and implemented using LabVIEW software and provides a user-friendly interface that enables control of several clinical radiographic imaging modes of the MAF including: fluoroscopy, roadmap, radiography, and digital-subtraction-angiography (DSA). Using the automatic controls, the MAF detector can be moved to the deployed position, in front of a standard FPD, whenever higher resolution is needed during angiographic or interventional vascular imaging procedures. To minimize any possible negative impact to image guidance with the two detector systems, it is essential to have a well-designed workflow that enables smooth deployment of the MAF at critical stages of clinical procedures. For the ultimate success of this new imaging capability, a clear understanding of the workflow design is essential. This presentation provides a detailed description and demonstration of such a workflow design. PMID:25302003

  15. High-Resolution MR Imaging of the Human Brainstem In vivo at 7 Tesla

    PubMed Central

    Deistung, Andreas; Schäfer, Andreas; Schweser, Ferdinand; Biedermann, Uta; Güllmar, Daniel; Trampel, Robert; Turner, Robert; Reichenbach, Jürgen R.

    2013-01-01

    The human brainstem, which comprises a multitude of axonal nerve fibers and nuclei, plays an important functional role in the human brain. Depicting its anatomy non-invasively with high spatial resolution may thus in turn help to better relate normal and pathological anatomical variations to medical conditions as well as neurological and peripheral functions. We explored the potential of high-resolution magnetic resonance imaging (MRI) at 7 T for depicting the intricate anatomy of the human brainstem in vivo by acquiring and generating images with multiple contrasts: T2-weighted images, quantitative maps of longitudinal relaxation rate (R1 maps) and effective transverse relaxation rate (R2* maps), magnetic susceptibility maps, and direction-encoded track-density images. Images and quantitative maps were compared with histological stains and anatomical atlases to identify nerve nuclei and nerve fibers. Among the investigated contrasts, susceptibility maps displayed the largest number of brainstem structures. Contrary to R1 maps and T2-weighted images, which showed rather homogeneous contrast, R2* maps, magnetic susceptibility maps, and track-density images clearly displayed a multitude of smaller and larger fiber bundles. Several brainstem nuclei were identifiable in sections covering the pons and medulla oblongata, including the spinal trigeminal nucleus and the reticulotegmental nucleus on magnetic susceptibility maps as well as the inferior olive on R1, R2*, and susceptibility maps. The substantia nigra and red nuclei were visible in all contrasts. In conclusion, high-resolution, multi-contrast MR imaging at 7 T is a versatile tool to non-invasively assess the individual anatomy and tissue composition of the human brainstem. PMID:24194710

  16. Scatter reduction for high resolution image detectors with a region of interest attenuator.

    PubMed

    Jain, Amit; Bednarek, Daniel R; Rudin, Stephen

    2014-03-19

    Compton scatter is the main interaction of x-rays with objects undergoing radiographic and fluoroscopic imaging procedures. Such scatter is responsible for reducing image signal to noise ratio which can negatively impact object detection especially for low contrast objects. To reduce scatter, possible methods are smaller fields-of-view, larger air gaps and the use of an anti-scatter grid. Smaller fields of view may not be acceptable and scanned-beam radiography is not practical for real-time imaging. Air gaps can increase geometric unsharpness and thus degrade image resolution. Deployment of an anti-scatter grid is not well suited for high resolution imagers due to the unavailability of high line density grids needed to prevent grid-line artifacts. However, region of interest (ROI) imaging can be used not only for dose reduction but also for scatter reduction in the ROI. The ROI region receives unattenuated x-rays while the peripheral region receives x-rays reduced in intensity by an ROI attenuator. The scatter within the ROI part of the image originates from both the unattenuated ROI and the attenuated peripheral region. The scatter contribution from the periphery is reduced in intensity because of the reduced primary x-rays in that region and the scatter fraction in the ROI is thus reduced. In this study, the scatter fraction for various kVp's, air-gaps and field sizes was measured for a uniform head equivalent phantom. The scatter fraction in the ROI was calculated using a derived scatter fraction formula, which was validated with experimental measurements. It is shown that use of a ROI attenuator can be an effective way to reduce both scatter and patient dose while maintaining the superior image quality of high resolution detectors.

  17. Exploring image data assimilation in the prospect of high-resolution satellite data

    NASA Astrophysics Data System (ADS)

    Verron, J. A.; Duran, M.; Gaultier, L.; Brankart, J. M.; Brasseur, P.

    2016-02-01

    Many recent works show the key importance of studying the ocean at fine scales including the meso- and submesoscales. Satellite observations such as ocean color data provide informations on a wide range of scales but do not directly provide information on ocean dynamics. Satellite altimetry provide informations on the ocean dynamic topography (SSH) but so far with a limited resolution in space and even more, in time. However, in the near future, high-resolution SSH data (e.g. SWOT) will give a vision of the dynamic topography at such fine space resolution. This raises some challenging issues for data assimilation in physical oceanography: develop reliable methodology to assimilate high resolution data, make integrated use of various data sets including biogeochemical data, and even more simply, solve the challenge of handling large amont of data and huge state vectors. In this work, we propose to consider structured information rather than pointwise data. First, we take an image data assimilation approach in studying the feasibility of inverting tracer observations from Sea Surface Temperature and/or Ocean Color datasets, to improve the description of mesoscale dynamics provided by altimetric observations. Finite Size Lyapunov Exponents are used as an image proxy. The inverse problem is formulated in a Bayesian framework and expressed in terms of a cost function measuring the misfits between the two images. Second, we explore the inversion of SWOT-like high resolution SSH data and more especially the various possible proxies of the actual SSH that could be used to control the ocean circulation at various scales. One focus is made on controlling the subsurface ocean from surface only data. A key point lies in the errors and uncertainties that are associated to SWOT data.

  18. A Comprehensive Approach to High-Resolution Daylight Imaging for SSA

    NASA Astrophysics Data System (ADS)

    Hart, M.; Jefferies, S.; Hope, D.; Nagy, J.; Swindle, R.

    2016-09-01

    High resolution daytime imaging of resident space objects (RSO) from the ground is presently severely challenging. At visible wavelengths, where diffraction-limited resolution is the highest before the atmosphere becomes opaque in the UV, shot noise from the bright background degrades the information that may be recovered from RSO imagery. Total exposure times must be limited in order to avoid motion blur induced either by the object's intrinsic rotation or simply by its orbital motion over the site. Fundamentally, then, one cannot collect enough light from the object to achieve adequate signal-to-noise ratio (SNR) in the presence of very high noise before the apparent shape of the object has changed. To overcome this limitation, we propose in this paper a suite of techniques which we believe will collectively enable high-resolution imaging during daylight. The approach, which has yet to be fully implemented, relies on a sequence of short-exposure images from a high-cadence camera together with simultaneous wave-front sensor (WFS) measurements acquired from a filtered sodium laser guide star. We then directly estimate the three-dimensional shape of the RSO using a formalism similar to the concept of deconvolution from wave-front sensing (DWFS). In this way, provided that the intrinsic shape of the RSO does not significantly change during the course of the observations, we can combine data from quite different pose angles in order to achieve a high resolution result with adequate SNR. By adopting this approach, we expect an improvement of 3-4 stellar magnitudes in the faintest satellites that may be characterized independent of the telescope and observing waveband. Furthermore, a model derived from observations by one sensor may be used as the basis for the restoration of data sets from widely disparate telescopes and sensor modalities; data fusion in this sense is a natural feature of the approach.

  19. Limitations of anti-scatter grids when used with high resolution image detectors.

    PubMed

    Singh, V; Jain, A; Bednarek, D R; Rudin, S

    2014-03-19

    Anti-scatter grids are used in fluoroscopic systems to improve image quality by absorbing scattered radiation. A stationary Smit Rontgen X-ray grid (line density: 70 lines/cm, grid ratio: 13:1) was used with a flat panel detector (FPD) of pixel size 194 micron and a high-resolution CMOS detector, the Dexela 1207 with pixel size of 75 microns. To investigate the effectiveness of the grid, a simulated artery block was placed in a modified uniform frontal head phantom and imaged with both the FPD and the Dexela for an approximately 15 × 15 cm field of view (FOV). The contrast improved for both detectors with the grid. The contrast-to-noise ratio (CNR) does not increase as much in the case of the Dexela as it improves in the case of the FPD. Since the total noise in a single frame increases substantially for the Dexela compared to the FPD when the grid is used, the CNR is degraded. The increase in the quantum noise per frame would be similar for both detectors when the grid is used due to the attenuation of radiation, but the fixed pattern noise caused by the grid was substantially higher for the Dexela compared to the FPD and hence caused a severe reduction of CNR. Without further corrective methods this grid should not be used with high-resolution fluoroscopic detectors because the CNR does not improve significantly and the visibility of low contrast details may be reduced. Either an anti-scatter grid of different design or an additional image processing step when using a similar grid would be required to deal with the problem of scatter for high resolution detectors and the structured noise of the grid pattern.

  20. Limitations of anti-scatter grids when used with high resolution image detectors

    PubMed Central

    Singh, V.; Jain, A.; Bednarek, D. R.; Rudin, S.

    2014-01-01

    Anti-scatter grids are used in fluoroscopic systems to improve image quality by absorbing scattered radiation. A stationary Smit Rontgen X-ray grid (line density: 70 lines/cm, grid ratio: 13:1) was used with a flat panel detector (FPD) of pixel size 194 micron and a high-resolution CMOS detector, the Dexela 1207 with pixel size of 75 microns. To investigate the effectiveness of the grid, a simulated artery block was placed in a modified uniform frontal head phantom and imaged with both the FPD and the Dexela for an approximately 15 × 15 cm field of view (FOV). The contrast improved for both detectors with the grid. The contrast-to-noise ratio (CNR) does not increase as much in the case of the Dexela as it improves in the case of the FPD. Since the total noise in a single frame increases substantially for the Dexela compared to the FPD when the grid is used, the CNR is degraded. The increase in the quantum noise per frame would be similar for both detectors when the grid is used due to the attenuation of radiation, but the fixed pattern noise caused by the grid was substantially higher for the Dexela compared to the FPD and hence caused a severe reduction of CNR. Without further corrective methods this grid should not be used with high-resolution fluoroscopic detectors because the CNR does not improve significantly and the visibility of low contrast details may be reduced. Either an anti-scatter grid of different design or an additional image processing step when using a similar grid would be required to deal with the problem of scatter for high resolution detectors and the structured noise of the grid pattern. PMID:25309101

  1. Limitations of anti-scatter grids when used with high resolution image detectors

    NASA Astrophysics Data System (ADS)

    Singh, V.; Jain, A.; Bednarek, D. R.; Rudin, S.

    2014-03-01

    Anti-scatter grids are used in fluoroscopic systems to improve image quality by absorbing scattered radiation. A stationary Smit Rontgen X-ray grid (line density: 70 lines/cm, grid ratio: 13:1) was used with a flat panel detector (FPD) of pixel size 194 micron and a high-resolution CMOS detector, the Dexela 1207 with pixel size of 75 microns. To investigate the effectiveness of the grid, a simulated artery block was placed in a modified uniform frontal head phantom and imaged with both the FPD and the Dexela for an approximately 15 x 15 cm field of view (FOV). The contrast improved for both detectors with the grid. The contrast-to-noise ratio (CNR) does not increase as much in the case of the Dexela as it improves in the case of the FPD. Since the total noise in a single frame increases substantially for the Dexela compared to the FPD when the grid is used, the CNR is degraded. The increase in the quantum noise per frame would be similar for both detectors when the grid is used due to the attenuation of radiation, but the fixed pattern noise caused by the grid was substantially higher for the Dexela compared to the FPD and hence caused a severe reduction of CNR. Without further corrective methods this grid should not be used with high-resolution fluoroscopic detectors because the CNR does not improve significantly and the visibility of low contrast details may be reduced. Either an anti-scatter grid of different design or an additional image processing step when using a similar grid would be required to deal with the problem of scatter for high resolution detectors and the structured noise of the grid pattern.

  2. Micrometer scale contact lens movements imaged by ultra-high resolution optical coherence tomography

    PubMed Central

    Cui, Lele; Shen, Meixiao; Wang, Michael R.; Wang, Jianhua

    2011-01-01

    PURPOSE To dynamically evaluate contact lens movement and ocular surface shape using ultra-high resolution and ultra-long scan depth optical coherence tomography (OCT). DESIGN Clinical research study of a laboratory technique. METHODS Four different types of soft contact lenses were tested on the left eye of 10 subjects (6 males and 4 females). Lenses edges at primary gaze and temporal and nasal gazes were imaged by ultra-high resolution OCT. Excursion lag was obtained as the distance between the lens edge at primary gaze and immediately after the eye was quickly turned either nasally or temporally. The inferior lens edges were imaged continuously to track vertical movements during blinking. Ultra-long scan depth OCT provided quantifiable images of the ocular surface, and the contour was acquired using custom software. RESULTS Excursion lag at the horizontal meridian was 366 ± 134 μm at temporal gaze and 320 ± 137 μm at nasal gaze (P > .05). The lens uplift at the vertical meridian was 342 ± 155 μm after blinking. There were significant differences in horizontal lags and vertical movements among different lenses (P < .05). Horizontal lags were correlated with radii of curvatures and sagittal heights at 6- and 14- mm horizontal meridian radii (P < .05). The blink-induced lens uplift first lowered by 104 ± 8 μm, and then lifted 342 ± 155 μm after the blink. CONCLUSIONS Ultra-high resolution and ultra-long scan depth OCT can assess micrometer scale lens movements and ocular surface contours. Both lens design and ocular surface shape affected lens movements. PMID:21920493

  3. High-resolution three-dimensional imaging and analysis of rock falls in Yosemite valley, California

    USGS Publications Warehouse

    Stock, Gregory M.; Bawden, G.W.; Green, J.K.; Hanson, E.; Downing, G.; Collins, B.D.; Bond, S.; Leslar, M.

    2011-01-01

    We present quantitative analyses of recent large rock falls in Yosemite Valley, California, using integrated high-resolution imaging techniques. Rock falls commonly occur from the glacially sculpted granitic walls of Yosemite Valley, modifying this iconic landscape but also posing signifi cant potential hazards and risks. Two large rock falls occurred from the cliff beneath Glacier Point in eastern Yosemite Valley on 7 and 8 October 2008, causing minor injuries and damaging structures in a developed area. We used a combination of gigapixel photography, airborne laser scanning (ALS) data, and ground-based terrestrial laser scanning (TLS) data to characterize the rock-fall detachment surface and adjacent cliff area, quantify the rock-fall volume, evaluate the geologic structure that contributed to failure, and assess the likely failure mode. We merged the ALS and TLS data to resolve the complex, vertical to overhanging topography of the Glacier Point area in three dimensions, and integrated these data with gigapixel photographs to fully image the cliff face in high resolution. Three-dimensional analysis of repeat TLS data reveals that the cumulative failure consisted of a near-planar rock slab with a maximum length of 69.0 m, a mean thickness of 2.1 m, a detachment surface area of 2750 m2, and a volume of 5663 ?? 36 m3. Failure occurred along a surfaceparallel, vertically oriented sheeting joint in a clear example of granitic exfoliation. Stress concentration at crack tips likely propagated fractures through the partially attached slab, leading to failure. Our results demonstrate the utility of high-resolution imaging techniques for quantifying far-range (>1 km) rock falls occurring from the largely inaccessible, vertical rock faces of Yosemite Valley, and for providing highly accurate and precise data needed for rock-fall hazard assessment. ?? 2011 Geological Society of America.

  4. High resolution diffraction imaging of crystals grown in microgravity and closely related terrestrial crystals

    NASA Technical Reports Server (NTRS)

    Steiner, B.; Dobbyn, R.; Black, D.; Burdette, H.; Kuriyama, M.; Spal, R.; Vandenberg, L.; Fripp, A.; Simchick, R.; Lal, R.

    1991-01-01

    Irregularities found in three crystals grown in space, in four crystals grown entirely on the ground were examined and compared. Irregularities were observed in mercuric iodide, lead tin telluride, triglycine sulfate, and gallium arsenide by high resolution synchrotron x radiation diffraction imaging. Radiation detectors made from mercuric iodide crystals grown in microgravity were reported to perform far better than conventional detectors grown from the same material under full gravity. Effort is now underway to reproduce these 'space' crystals, optimize their properties, and extend comparable superiority to other types of materials.

  5. High Resolution Pulse Compression Imaging Using Super Resolution FM-Chirp Correlation Method (SCM)

    NASA Astrophysics Data System (ADS)

    Fujiwara, M.; Okubo, K.; Tagawa, N.

    This study addresses the issue of the super-resolution pulse compression technique (PCT) for ultrasound imaging. Time resolution of multiple ultrasonic echoes using the FM-Chirp PCT is limited by the bandwidth of the sweep-frequency. That is, the resolution depends on the sharpness of auto-correlation function. We propose the Super resolution FM-Chirp correlation Method (SCM) and evaluate its performance. This method is based on the multiple signal classification (MUSIC) algorithm. Our simulations were made for the model assuming multiple signals reflected from some scatterers. We confirmed that SCM detects time delay of complicated reflected signals successfully with high resolution.

  6. A high-resolution magnetic imaging system based on a SQUID magnetometer

    SciTech Connect

    Hibbs, A.D.; Sager, R.E.; Cox, D.W.; Aukerman, T.H.; Sage, T.A.; Landis, R.S. )

    1992-07-01

    We have recently developed a high-resolution magnetic imaging system based on an array of five superconducting pickup coils located within 1 mm of room temperature. The pickup coils are 1.70 mm in diameter and spaced 2.5 mm apart allowing spatial resolution of order 1 mm. They are each connected to an rf SQUID and have a magnetic field sensitivity of 3 pT/{radical}Hz. The system includes a three axis nonmagnetic translation table for mounting the sample, a stage for temperature control, and complete computer control of all functions.

  7. Observations of the quasi 2-day wave from the High Resolution Doppler Imager on UARS

    NASA Technical Reports Server (NTRS)

    Wu, D. L.; Hays, P. B.; Skinner, W. R.; Marshall, A. R.; Burrage, M. D.; Lieberman, R. S.; Ortland, D. A.

    1993-01-01

    A strong westward traveling oscillation, with a period of 2 days and zonal wave number 3, is observed in the mesospheric and lower thermospheric winds from the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS). The important events happen in January, July, and September/October, of which the occurrence in January is the strongest with an amplitude over 60 m/s. Detailed analyses for the periods of January 1992 and January 1993 reveal a cause-and-effect relationship in the wave developing process at 95 km. The global structures of the wave amplitude and phase are also presented.

  8. Optical fibers for high-resolution in vivo microendoscopic fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Oh, Gyungseok; Chung, Euiheon; Yun, Seok H.

    2013-12-01

    Optical fiber-based high-resolution fluorescence imaging techniques have promising applications in clinical practice and preclinical research using animals. Here we review the instrumentation and applications of microendoscopy based on various types of optical fibers. Single-mode fibers and double-clad fibers have been widely used for delivering light from light sources to tissues and collecting light from tissues to photodetectors. Coherent fiber bundles, cylindrical graded-index lenses, and multi-mode fibers have been employed in both beam-scanning and non-scanning microscopy. With continuing advances of optical fiber technologies, further innovations in optical microendoscopy are expected.

  9. High-resolution imaging and target designation through clouds or smoke

    DOEpatents

    Perry, Michael D.

    2003-01-01

    A method and system of combining gated intensifiers and advances in solid-state, short-pulse laser technology, compact systems capable of producing high resolution (i.e., approximately less than 20 centimeters) optical images through a scattering medium such as dense clouds, fog, smoke, etc. may be achieved from air or ground based platforms. Laser target designation through a scattering medium is also enabled by utilizing a short pulse illumination laser and a relatively minor change to the detectors on laser guided munitions.

  10. High-resolution depth electrode localization and imaging in patients with pharmacologically intractable epilepsy

    PubMed Central

    Ekstrom, Arne; Suthana, Nanthia; Behnke, Eric; Salamon, Noriko; Bookheimer, Susan; Fried, Itzhak

    2009-01-01

    Localization and targeting of depth electrodes in specific regions of the human brain is critical for accurate clinical diagnoses and treatment as well as for neuroscientific electrophysiological research. By using high-resolution magnetic resonance imaging combined with 2D computational unfolding, the authors present a method that improves electrode localization in the medial temporal lobe. This method permits visualization of electrode placements in subregions of the hippocampus and parahippocampal gyrus, allowing for greater specificity in relating electrophysiological and anatomical features in the human medial temporal lobe. Such methods may be extended to therapeutic procedures targeting specific neuronal circuitry in subfields of structures deep in the human brain. PMID:18377264

  11. The LINC-NIRVANA high resolution imager: challenges from the lab to first light

    NASA Astrophysics Data System (ADS)

    Herbst, T. M.; Ragazzoni, R.; Eckart, A.; Weigelt, G.

    2014-07-01

    We present an update on LINC-NIRVANA (LN), an innovative, high-resolution infrared imager for the Large Binocular Telescope (LBT). LN uses Multi-Conjugate Adaptive Optics (MCAO) for high-sky-coverage diffraction-limited imagery and interferometric beam combination. The last two years have seen both successes and challenges. On the one hand, final integration is proceeding well in the lab. We also achieved First Light at the LBT with the Pathfinder experiment. On the other hand, funding constraints have forced a significant re-planning of the overall instrument implementation. This paper presents our progress and plans for bringing the instrument online at the telescope.

  12. Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI): Monolithic Interferometer Design and Test

    NASA Astrophysics Data System (ADS)

    Harlander, John M.; Englert, Christoph R.; Brown, Charles M.; Marr, Kenneth D.; Miller, Ian J.; Zastera, Vaz; Bach, Bernhard W.; Mende, Stephen B.

    2017-06-01

    The design and laboratory tests of the interferometers for the Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument which measures thermospheric wind and temperature for the NASA-sponsored Ionospheric Connection (ICON) Explorer mission are described. The monolithic interferometers use the Doppler Asymmetric Spatial Heterodyne (DASH) Spectroscopy technique for wind measurements and a multi-element photometer approach to measure thermospheric temperatures. The DASH technique and overall optical design of the MIGHTI instrument are described in an overview followed by details on the design, element fabrication, assembly, laboratory tests and thermal control of the interferometers that are the heart of MIGHTI.

  13. AM Multipurpose High-Resolution Imaging Topological Radar (ITR): reverse engineering and artworks monitoring and restoration

    NASA Astrophysics Data System (ADS)

    Guarneri, Massimiliano; Bartolini, Luciano; Fornetti, Giorgio; Ferri De Collibus, Mario; De Dominicis, Luigi; Paglia, Emiliano; Poggi, Claudio; Ricci, Roberto

    2005-08-01

    A high resolution Amplitude Modulated Imaging Laser Radar (AM-LR) sensor has recently been developed, aimed to accurately reconstructing 3D digital models of real targets - either single objects or large amplitude complex scenes. The system sounding beam can be swept linearly across the object or circularly around it, by placing the object on a controlled rotating platform. Both intensity and phase shift of the back-scattered light are then collected and processed, providing respectively a shade-free photographic-like picture and accurate range data in the form of a range or depth image, with accuracy depending mainly on the laser modulation frequency. The development of software, suitable for simultaneous 3D rendering of the intensity and absolute distance data collected by the ITR, constitutes one of the main objectives of the research activity, whatever is the application pursued. In fact, high resolution AM-LR systems have a great interest for their potentials in accurate 3D imaging of valuable objects which must be preserved in digital archives. Examples range from artwork monitoring, cataloguing and restoration from sparse fragments, to medicine for non-hazardous diagnostics and fast design of bio-compatible prostheses, to microtechnology in the miniaturization of macro-components (plastic prototypes, quality control). Several meaningful results of measurements executed in various important European archaeological sites, in particular Santa Maria Antiqua church situated in Fori Imperiali area in Rome and Costanza (Romania), involving 3D color mapped representation are also presented.

  14. On chip cryo-anesthesia of Drosophila larvae for high resolution in vivo imaging applications.

    PubMed

    Chaudhury, Amrita Ray; Insolera, Ryan; Hwang, Ran-Der; Fridell, Yih-Woei; Collins, Catherine; Chronis, Nikos

    2017-06-27

    We present a microfluidic chip for immobilizing Drosophila melanogaster larvae for high resolution in vivo imaging. The chip creates a low-temperature micro-environment that anaesthetizes and immobilizes the larva in under 3 minutes. We characterized the temperature distribution within the chip and analyzed the resulting larval body movement using high resolution fluorescence imaging. Our results indicate that the proposed method minimizes submicron movements of internal organs and tissue without affecting the larva physiology. It can be used to continuously immobilize larvae for short periods of time (minutes) or for longer periods (several hours) if used intermittently. The same chip can be used to accommodate and immobilize arvae across all developmental stages (1st instar to late 3rd instar), and loading larvae onto the chip does not require any specialized skills. To demonstrate the usability of the chip, we observed mitochondrial trafficking in neurons from the cell bodies to the axon terminals along with mitochondrial fusion and neuro-synaptic growth through time in intact larvae. Besides studying sub-cellular processes and cellular development, we envision the use of on chip cryo-anesthesia in a wide variety of biological in vivo imaging applications, including observing organ development of the salivary glands, fat bodies and body-wall muscles.

  15. High-resolution imaging of biological cell with fiber-based composite interferometer

    NASA Astrophysics Data System (ADS)

    Hsu, Hsiu-I.; Chang, Chun-Wei; Hou, Max T.-K.; Hsu, I.-Jen

    2009-02-01

    We proposed and demonstrated an optical system for high-speed and high-resolution imaging of surface profiles. The system is a fiber-based composite interferometer in which a Michelson interferometer is used for the measurement of the surface profile of the sample and a Mach-Zehnder interferometer is used for compensation of phase deviation due to the systematic errors and environmental perturbations. In the system, a laser diode with wavelength of 531 nm was used as the light source. A two-axis translation stage was used for lateral scanning of the sample. In the reference arm, a reflection mirror was arranged on a translation stage driven by a piezoelectric transducer as the axial scanning component. The phase difference between the interferograms of both interferometers was acquired to obtain the surface height of the sample. The axial accuracy of +/-5 nm was achieved where the imaging was acquired within one minute for a frame. The lateral resolution was at the diffraction limit of light. The system possesses the advantages of low cost, portability and flexibility. Furthermore, it can perform high-resolution imaging in large area without special shielding of the system as well as any special preparation of the sample.

  16. GPU-based rectification of high-resolution remote sensing stereo images

    NASA Astrophysics Data System (ADS)

    Lukač, Niko; Žalik, Borut

    2014-10-01

    One of the major challenges in the topographic mapping and fast generation of digital terrain or surface models from stereo optical aerial or satellite imagery is the stereo rectification preprocessing step. The general case is the use of extrinsic and intrinsic parameters from each calibrated camera, in order to establish epipolar geometry. Stereo rectification consists of geometric transformation and image sub-pixel resampling. Such a task is computationally demanding when dealing with high-resolution optical imagery. This presents an increasingly evident problem as the remote sensing technologies are becoming more accurate, causing even higher computational demands. This paper proposes a novel method for fast rectification of stereo images pairs to epipolar geometry by using General Purpose computing on Graphics Processing Units (GPGPU). The method is capable of resampling large high-resolution imagery on-the-fly, due to efficient out-of-core processing. In the experiments a runtime comparison was made between the proposed GPU-based and multi-core CPU methods over a dataset consisting of 420 stereo aerial images, where the proposed method achieved a significant speedup.

  17. An efficient photogrammetric stereo matching method for high-resolution images

    NASA Astrophysics Data System (ADS)

    Li, Yingsong; Zheng, Shunyi; Wang, Xiaonan; Ma, Hao

    2016-12-01

    Stereo matching of high-resolution images is a great challenge in photogrammetry. The main difficulty is the enormous processing workload that involves substantial computing time and memory consumption. In recent years, the semi-global matching (SGM) method has been a promising approach for solving stereo problems in different data sets. However, the time complexity and memory demand of SGM are proportional to the scale of the images involved, which leads to very high consumption when dealing with large images. To solve it, this paper presents an efficient hierarchical matching strategy based on the SGM algorithm using single instruction multiple data instructions and structured parallelism in the central processing unit. The proposed method can significantly reduce the computational time and memory required for large scale stereo matching. The three-dimensional (3D) surface is reconstructed by triangulating and fusing redundant reconstruction information from multi-view matching results. Finally, three high-resolution aerial date sets are used to evaluate our improvement. Furthermore, precise airborne laser scanner data of one data set is used to measure the accuracy of our reconstruction. Experimental results demonstrate that our method remarkably outperforms in terms of time and memory savings while maintaining the density and precision of the 3D cloud points derived.

  18. Multimodal adaptive optics for depth-enhanced high-resolution ophthalmic imaging

    NASA Astrophysics Data System (ADS)

    Hammer, Daniel X.; Mujat, Mircea; Iftimia, Nicusor V.; Lue, Niyom; Ferguson, R. Daniel

    2010-02-01

    We developed a multimodal adaptive optics (AO) retinal imager for diagnosis of retinal diseases, including glaucoma, diabetic retinopathy (DR), age-related macular degeneration (AMD), and retinitis pigmentosa (RP). The development represents the first ever high performance AO system constructed that combines AO-corrected scanning laser ophthalmoscopy (SLO) and swept source Fourier domain optical coherence tomography (SSOCT) imaging modes in a single compact clinical prototype platform. The SSOCT channel operates at a wavelength of 1 μm for increased penetration and visualization of the choriocapillaris and choroid, sites of major disease activity for DR and wet AMD. The system is designed to operate on a broad clinical population with a dual deformable mirror (DM) configuration that allows simultaneous low- and high-order aberration correction. The system also includes a wide field line scanning ophthalmoscope (LSO) for initial screening, target identification, and global orientation; an integrated retinal tracker (RT) to stabilize the SLO, OCT, and LSO imaging fields in the presence of rotational eye motion; and a high-resolution LCD-based fixation target for presentation to the subject of stimuli and other visual cues. The system was tested in a limited number of human subjects without retinal disease for performance optimization and validation. The system was able to resolve and quantify cone photoreceptors across the macula to within ~0.5 deg (~100-150 μm) of the fovea, image and delineate ten retinal layers, and penetrate to resolve targets deep into the choroid. In addition to instrument hardware development, analysis algorithms were developed for efficient information extraction from clinical imaging sessions, with functionality including automated image registration, photoreceptor counting, strip and montage stitching, and segmentation. The system provides clinicians and researchers with high-resolution, high performance adaptive optics imaging to help

  19. High resolution 3.0 Tesla MR imaging findings in patients with bilateral Madelung's deformity.

    PubMed

    Stehling, Christoph; Langer, Martin; Nassenstein, Isabelle; Bachmann, Rainald; Heindel, Walter; Vieth, Volker

    2009-08-01

    Madelung deformity (MD) is a rare, normally painful abnormality of the wrist and forearm which characteristically begins in adolescence. Usually the deformity appears between the age of 8 and 14 years, often progressing from initially mild functional pain to fatigue and loss of strength and finally, reduced mobility. We present the MR-findings in three patients with bilateral MD, using a high-resolution imaging protocol adapted for 3.0 Tesla (3.0 T) examinations. Wrist images of three patients were acquired at a 3.0 T Scanner (Gyroscan Intera, Philips Medical Systems, Best, The Netherlands), using a dedicated phased array coil. The imaging protocol consisted of coronal T1-weighted Turbo-spin-echo (T1w-TSE) and coronal and sagittal T2-weighted TSE sequences (T2w-TSE). MR-images of these three girls demonstrated severe volar bayonet configuration of the forearms with a dorsal prominence of the ulnar head, also a curved distal radial articular surface with increased ulnar angulation, due to a deceleration of growth in the ulnar portion of the distal epiphysis. The proximal carpal row showed pyramidal configuration. Also visible was a prominent short radiolunate ligament, the so called Vickers ligament, which originates from the ulnar border of the radius, inserts into the volar pole of the lunate and likely contributes to carpal pyramidalization. Furthermore, the images demonstrated an anomalous hypertrophied and elongated volar radiotriquetral ligament which, to our knowledge, has been described elsewhere only in another case. High resolution imaging at 3.0 T permitted a detailed analysis of the complex pathomorphology in patients with MD. Investing the better signal-to-noise ratio at higher field strengths into spatial resolution an excellent image quality could be obtained, depicting the Vickers ligament and the anomalous volar radiotriquetral ligament in this rare disease.

  20. High-resolution adaptive optics retinal imaging of cellular structure in choroideremia.

    PubMed

    Morgan, Jessica I W; Han, Grace; Klinman, Eva; Maguire, William M; Chung, Daniel C; Maguire, Albert M; Bennett, Jean

    2014-09-04

    We characterized retinal structure in patients and carriers of choroideremia using adaptive optics and other high resolution modalities. A total of 57 patients and 18 carriers of choroideremia were imaged using adaptive optics scanning light ophthalmoscopy (AOSLO), optical coherence tomography (OCT), autofluorescence (AF), and scanning light ophthalmoscopy (SLO). Cone density was measured in 59 eyes of 34 patients where the full cone mosaic was observed. The SLO imaging revealed scalloped edges of RPE atrophy and large choroidal vessels. The AF imaging showed hypo-AF in areas of degeneration, while central AF remained present. OCT images showed outer retinal tubulations and thinned RPE/interdigitation layers. The AOSLO imaging revealed the cone mosaic in central relatively intact retina, and cone density was either reduced or normal at 0.5 mm eccentricity. The border of RPE atrophy showed abrupt loss of the cone mosaic at the same location. The AF imaging in comparison with AOSLO showed RPE health may be compromised before cone degeneration. Other disease features, including visualization of choroidal vessels, hyper-reflective clumps of cones, and unique retinal findings, were tabulated to show the frequency of occurrence and model disease progression. The data support the RPE being one primary site of degeneration in patients with choroideremia. Photoreceptors also may degenerate independently. High resolution imaging, particularly AOSLO in combination with OCT, allows single cell analysis of disease in choroideremia. These modalities promise to be useful in monitoring disease progression, and in documenting the efficacy of gene and cell-based therapies for choroideremia and other diseases as these therapies emerge. (ClinicalTrials.gov number, NCT01866371.). Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  1. Computational high-resolution heart phantoms for medical imaging and dosimetry simulations

    NASA Astrophysics Data System (ADS)

    Gu, Songxiang; Gupta, Rajiv; Kyprianou, Iacovos

    2011-09-01

    Cardiovascular disease in general and coronary artery disease (CAD) in particular, are the leading cause of death worldwide. They are principally diagnosed using either invasive percutaneous transluminal coronary angiograms or non-invasive computed tomography angiograms (CTA). Minimally invasive therapies for CAD such as angioplasty and stenting are rendered under fluoroscopic guidance. Both invasive and non-invasive imaging modalities employ ionizing radiation and there is concern for deterministic and stochastic effects of radiation. Accurate simulation to optimize image quality with minimal radiation dose requires detailed, gender-specific anthropomorphic phantoms with anatomically correct heart and associated vasculature. Such phantoms are currently unavailable. This paper describes an open source heart phantom development platform based on a graphical user interface. Using this platform, we have developed seven high-resolution cardiac/coronary artery phantoms for imaging and dosimetry from seven high-quality CTA datasets. To extract a phantom from a coronary CTA, the relationship between the intensity distribution of the myocardium, the ventricles and the coronary arteries is identified via histogram analysis of the CTA images. By further refining the segmentation using anatomy-specific criteria such as vesselness, connectivity criteria required by the coronary tree and image operations such as active contours, we are able to capture excellent detail within our phantoms. For example, in one of the female heart phantoms, as many as 100 coronary artery branches could be identified. Triangular meshes are fitted to segmented high-resolution CTA data. We have also developed a visualization tool for adding stenotic lesions to the coronaries. The male and female heart phantoms generated so far have been cross-registered and entered in the mesh-based Virtual Family of phantoms with matched age/gender information. Any phantom in this family, along with user

  2. High resolution MR imaging of pelvic lymph nodes at 7 Tesla.

    PubMed

    Philips, Bart W J; Fortuin, Ansje S; Orzada, Stephan; Scheenen, Tom W J; Maas, Marnix C

    2017-09-01

    Pelvic lymph node (PLN) metastases are often smaller than 5 mm and difficult to detect. This work presents a method to perform PLN imaging with ultrahigh-field MRI, using spectrally selective excitation to acquire water and lipid-selective imaging at high spatial resolution. A 3D water-selective multigradient echo (mGRE) sequence and lipid-selective gradient echo (GRE) sequence were tested in six healthy volunteers on a 7 Tesla (T) MRI system, using time interleaved acquisition of modes (TIAMO) to improve image homogeneity. The size distribution of the first 10 iliac PLNs detected in each volunteer was determined, and the contrast-to-noise ratio (CNR) of these lymph nodes (LNs) was compared with the individual mGRE images, sum-of-squares echo addition, and computed T2*-weighted images derived from the T2* fits. LN imaging was acquired robustly at ultrahigh field with high resolution and homogeneous lipid or water-selective contrast. PLNs down to 1.5-mm short axis were detected with mean ± standard error of the mean (SEM) short and long axes of 2.2 ± 0.1 and 3.7 ± 0.2 mm, respectively. Computed T2*-weighted imaging allowed flexibility in T2* contrast while featuring a CNR up to 90% of the sum-of-squares echo addition. Ultrahigh-field MRI in combination with TIAMO and frequency-selective excitation enables high-resolution, large field-of-view MRI of the lower abdomen, and may ultimately be suitable for detecting small PLN metastases. Magn Reson Med 78:1020-1028, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  3. Lensless high-resolution on-chip optofluidic microscopes for Caenorhabditis elegans and cell imaging.

    PubMed

    Cui, Xiquan; Lee, Lap Man; Heng, Xin; Zhong, Weiwei; Sternberg, Paul W; Psaltis, Demetri; Yang, Changhuei

    2008-08-05

    Low-cost and high-resolution on-chip microscopes are vital for reducing cost and improving efficiency for modern biomedicine and bioscience. Despite the needs, the conventional microscope design has proven difficult to miniaturize. Here, we report the implementation and application of two high-resolution (approximately 0.9 microm for the first and approximately 0.8 microm for the second), lensless, and fully on-chip microscopes based on the optofluidic microscopy (OFM) method. These systems abandon the conventional microscope design, which requires expensive lenses and large space to magnify images, and instead utilizes microfluidic flow to deliver specimens across array(s) of micrometer-size apertures defined on a metal-coated CMOS sensor to generate direct projection images. The first system utilizes a gravity-driven microfluidic flow for sample scanning and is suited for imaging elongate objects, such as Caenorhabditis elegans; and the second system employs an electrokinetic drive for flow control and is suited for imaging cells and other spherical/ellipsoidal objects. As a demonstration of the OFM for bioscience research, we show that the prototypes can be used to perform automated phenotype characterization of different Caenorhabditis elegans mutant strains, and to image spores and single cellular entities. The optofluidic microscope design, readily fabricable with existing semiconductor and microfluidic technologies, offers low-cost and highly compact imaging solutions. More functionalities, such as on-chip phase and fluorescence imaging, can also be readily adapted into OFM systems. We anticipate that the OFM can significantly address a range of biomedical and bioscience needs, and engender new microscope applications.

  4. The P2L method of mismatch detection for push broom high-resolution satellite images

    NASA Astrophysics Data System (ADS)

    Wan, Yi; Zhang, Yongjun

    2017-08-01

    RANSAC-based mismatch detection methods are widely used in the geometric registration of images. Despite their prevalence, setting the detection thresholds for different situations continues to be difficult without an appropriate geometric model. In high-resolution satellite images, simple image-space transformations are commonly influenced by the terrain or elevation errors. This paper introduces a new method, called the P2L method, which uses the distance between the transformed right image point and the segment of the corresponding epipolar line to distinguish the correct matches and mismatches. The affine model of the P2L method is solved to transform the right image points towards the segment of the epipolar line. The images for demonstration were acquired by GeoEye-1, Ikonos-2, and Ziyuan-3; and each type of image pairs had different intersection angles to explore the influence of the elevation error. The correct matches were manually collected and the mismatches were simulated. The experiments in this paper, which used only correct matches, demonstrated that this method was very robust with one specific threshold (five pixels) and was suitable for all the image pairs. The experiments using simulated mismatches and real matching points demonstrated that this method was able to distinguish most of the mismatches; and even for the image pair that had a 54-degree intersection angle, the ratio of mismatches was reduced from 81% to 11%.

  5. High-resolution iris image reconstruction from low-resolution imagery

    NASA Astrophysics Data System (ADS)

    Barnard, R.; Pauca, V. P.; Torgersen, T. C.; Plemmons, R. J.; Prasad, S.; van der Gracht, J.; Nagy, J.; Chung, J.; Behrmann, G.; Mathews, S.; Mirotznik, M.

    2006-08-01

    We investigate the use of a novel multi-lens imaging system in the context of biometric identification, and more specifically, for iris recognition. Multi-lenslet cameras offer a number of significant advantages over standard single-lens camera systems, including thin form-factor and wide angle of view. By using appropriate lenslet spacing relative to the detector pixel pitch, the resulting ensemble of images implicitly contains subject information at higher spatial frequencies than those present in a single image. Additionally, a multi-lenslet approach enables the use of observational diversity, including phase, polarization, neutral density, and wavelength diversities. For example, post-processing multiple observations taken with differing neutral density filters yields an image having an extended dynamic range. Our research group has developed several multi-lens camera prototypes for the investigation of such diversities. In this paper, we present techniques for computing a high-resolution reconstructed image from an ensemble of low-resolution images containing sub-pixel level displacements. The quality of a reconstructed image is measured by computing the Hamming distance between the Daugman 4 iris code of a conventional reference iris image, and the iris code of a corresponding reconstructed image. We present numerical results concerning the effect of noise and defocus blur in the reconstruction process using simulated data and report preliminary work on the reconstruction of actual iris data obtained with our camera prototypes.

  6. An Automated Platform for High-Resolution Tissue Imaging Using Nanospray Desorption Electrospray Ionization Mass Spectrometry

    SciTech Connect

    Lanekoff, Ingela T.; Heath, Brandi S.; Liyu, Andrey V.; Thomas, Mathew; Carson, James P.; Laskin, Julia

    2012-10-02

    An automated platform has been developed for acquisition and visualization of mass spectrometry imaging (MSI) data using nanospray desorption electrospray ionization (nano-DESI). The new system enables robust operation of the nano-DESI imaging source over many hours. This is achieved by controlling the distance between the sample and the probe by mounting the sample holder onto an automated XYZ stage and defining the tilt of the sample plane. This approach is useful for imaging of relatively flat samples such as thin tissue sections. Custom software called MSI QuickView was developed for visualization of large data sets generated in imaging experiments. MSI QuickView enables fast visualization of the imaging data during data acquisition and detailed processing after the entire image is acquired. The performance of the system is demonstrated by imaging rat brain tissue sections. High resolution mass analysis combined with MS/MS experiments enabled identification of lipids and metabolites in the tissue section. In addition, high dynamic range and sensitivity of the technique allowed us to generate ion images of low-abundance isobaric lipids. High-spatial resolution image acquired over a small region of the tissue section revealed the spatial distribution of an abundant brain metabolite, creatine, in the white and gray matter that is consistent with the literature data obtained using magnetic resonance spectroscopy.

  7. Optimal experimental design for nano-particle atom-counting from high-resolution STEM images.

    PubMed

    De Backer, A; De Wael, A; Gonnissen, J; Van Aert, S

    2015-04-01

    In the present paper, the principles of detection theory are used to quantify the probability of error for atom-counting from high resolution scanning transmission electron microscopy (HR STEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom-counting using the expression for the probability of error. We show that for very thin objects LAADF is optimal and that for thicker objects the optimal inner detector angle increases.

  8. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

    SciTech Connect

    Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.; Lauridsen, Erik M.; Bilheux, Hassina Z.; Molaison, Jamie J.; Santodonato, Louis J.; Tremsin, Anton S.; Grosse, Mirco; Morgano, Manuel; Kabra, Saurabh; Strobl, Markus

    2015-12-15

    High material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. This paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 °C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition, examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. This covers a broad field of research from fundamental to technological investigations of various types of materials and components.

  9. High resolution iridocorneal angle imaging system by axicon lens assisted gonioscopy

    PubMed Central

    Perinchery, Sandeep Menon; Shinde, Anant; Fu, Chan Yiu; Jeesmond Hong, Xun Jie; Baskaran, Mani; Aung, Tin; Murukeshan, Vadakke Matham

    2016-01-01

    Direct visualization and assessment of the iridocorneal angle (ICA) region with high resolution is important for the clinical evaluation of glaucoma. However, the current clinical imaging systems for ICA do not provide sufficient structural details due to their poor resolution. The key challenges in achieving high quality ICA imaging are its location in the anterior region of the eye and the occurrence of total internal reflection due to refractive index difference between cornea and air. Here, we report an indirect axicon assisted gonioscopy imaging probe with white light illumination. The illustrated results with this probe shows significantly improved visualization of structures in the ICA including TM region, compared to the current available tools. It could reveal critical details of ICA and expected to aid management by providing information that is complementary to angle photography and gonioscopy. PMID:27471000

  10. Rectal Imaging: Part I, High-Resolution MRI of Carcinoma of the Rectum at 3 T

    PubMed Central

    Halappa, Vivek Gowdra; Villalobos, Celia Pamela Corona; Bonekamp, Susanne; Gearhart, Susan L.; Efron, Jonathan; Herman, Joseph; Kamel, Ihab R.

    2013-01-01

    OBJECTIVE MRI is currently the imaging modality of choice for the detection, characterization, and staging of rectal cancer. A variety of examinations have been used for preoperative staging of rectal cancer, including digital rectal examination, endorectal (endoscopic) ultrasound, CT, and MRI. Endoscopic ultrasound is the imaging modality of choice for small and small superficial tumors. MRI is superior to CT for assessing invasion to adjacent organs and structures, especially low tumors that carry a high risk of recurrence. CONCLUSION High-resolution MRI is an accurate and sensitive imaging method delineating tumoral margins, mesorectal involvement, nodes, and distant metastasis. In this article, we will review the utility of rectal MRI in local staging, preoperative evaluation, and surgical planning. MRI at 3 T can accurately delineate the mesorectal fascia involvement, which is one of the main decision points in planning treatment. PMID:22733930

  11. Evolution of INO Uncooled Infrared Cameras Towards Very High Resolution Imaging

    NASA Astrophysics Data System (ADS)

    Bergeron, Alain; Jerominek, Hubert; Chevalier, Claude; Le Noc, Loïc; Tremblay, Bruno; Alain, Christine; Martel, Anne; Blanchard, Nathalie; Morissette, Martin; Mercier, Luc; Gagnon, Lucie; Couture, Patrick; Desnoyers, Nichola; Demers, Mathieu; Lamontagne, Frédéric; Lévesque, Frédéric; Verreault, Sonia; Duchesne, François; Lambert, Julie; Girard, Marc; Savard, Maxime; Châteauneuf, François

    2011-02-01

    Along the years INO has been involved in development of various uncooled infrared devices. Todays, the infrared imagers exhibit good resolutions and find their niche in numerous applications. Nevertheless, there is still a trend toward high resolution imaging for demanding applications. At the same time, low-resolution for mass market applications are sought for low-cost imaging solutions. These two opposite requirements reflect the evolution of infrared cameras from the origin, when only few pixel-count FPAs were available, to megapixel-count FPA of the recent years. This paper reviews the evolution of infrared camera technologies at INO from the uncooled bolometer detector capability up to the recent achievement of 1280×960 pixels infrared camera core using INO's patented microscan technology.

  12. Feasibility of transoral robotic-assisted high-resolution microendoscopic imaging of oropharyngeal squamous cell carcinoma.

    PubMed

    Patsias, Alexis; Giraldez-Rodriguez, Laureano; Polydorides, Alexandros D; Richards-Kortum, Rebecca; Anandasabapathy, Sharmila; Quang, Timothy; Sikora, Andrew G; Miles, Brett

    2015-08-01

    Transoral robotic-assisted oncologic surgery of the head and neck offers promising functional results. Nonetheless, the efficacy of oncologic surgery remains critically dependent on obtaining negative margins. We aimed to integrate a miniaturized high-resolution fiber-optic microendoscope (HRME), which provides real-time histological assessment, with the da Vinci robotic system (Intuitive Surgical, Sunnyvale, CA). Three patients undergoing transoral robotic surgery (TORS) were prospectively enrolled in this study. Optical imaging of the oropharynx was performed intraoperatively with the robotic-assisted HRME. All patients underwent the procedure successfully with no complications. The HRME was successfully integrated with the da Vinci robotic system. Several sites of the oropharynx and associated malignancy were imaged, which correlated with the standard histopathological analysis. Transoral robotic-assisted HRME imaging of the oropharynx is a safe and technically feasible approach, providing a real-time histological assessment and may serve as a valuable aid in oncologic surgery. © 2015 Wiley Periodicals, Inc.

  13. Nanoscale deformation analysis with high-resolution transmission electron microscopy and digital image correlation

    DOE PAGES

    Wang, Xueju; Pan, Zhipeng; Fan, Feifei; ...

    2015-09-10

    We present an application of the digital image correlation (DIC) method to high-resolution transmission electron microscopy (HRTEM) images for nanoscale deformation analysis. The combination of DIC and HRTEM offers both the ultrahigh spatial resolution and high displacement detection sensitivity that are not possible with other microscope-based DIC techniques. We demonstrate the accuracy and utility of the HRTEM-DIC technique through displacement and strain analysis on amorphous silicon. Two types of error sources resulting from the transmission electron microscopy (TEM) image noise and electromagnetic-lens distortions are quantitatively investigated via rigid-body translation experiments. The local and global DIC approaches are applied for themore » analysis of diffusion- and reaction-induced deformation fields in electrochemically lithiated amorphous silicon. As a result, the DIC technique coupled with HRTEM provides a new avenue for the deformation analysis of materials at the nanometer length scales.« less

  14. Nanoscale deformation analysis with high-resolution transmission electron microscopy and digital image correlation

    SciTech Connect

    Wang, Xueju; Pan, Zhipeng; Fan, Feifei; Wang, Jiangwei; Liu, Yang; Mao, Scott X.; Zhu, Ting; Xia, Shuman

    2015-09-10

    We present an application of the digital image correlation (DIC) method to high-resolution transmission electron microscopy (HRTEM) images for nanoscale deformation analysis. The combination of DIC and HRTEM offers both the ultrahigh spatial resolution and high displacement detection sensitivity that are not possible with other microscope-based DIC techniques. We demonstrate the accuracy and utility of the HRTEM-DIC technique through displacement and strain analysis on amorphous silicon. Two types of error sources resulting from the transmission electron microscopy (TEM) image noise and electromagnetic-lens distortions are quantitatively investigated via rigid-body translation experiments. The local and global DIC approaches are applied for the analysis of diffusion- and reaction-induced deformation fields in electrochemically lithiated amorphous silicon. As a result, the DIC technique coupled with HRTEM provides a new avenue for the deformation analysis of materials at the nanometer length scales.

  15. High-resolution, air-coupled ultrasonic imaging of thin materials.

    PubMed

    Gan, Tat-Hean; Hutchins, David A; Billson, Duncan R; Schindel, David W

    2003-11-01

    This paper describes the use of a focused air-coupled capacitance transducer combined with pulse compression techniques to form high-resolution images of thin materials in air. The focusing of the device is achieved by using an off-axis parabolic mirror. The lateral resolution of the focused transducer, operating over a bandwidth of 1.2 MHz, was found to be less than 0.5 mm. A combination of the focused transducer as a source and a planar receiver in through-transmission mode has been developed for the measurement of different features in paper products, with a lateral resolution in through-transmission imaging of approximately 0.4 mm. Images in air of thin samples such as bank notes, high-quality writing paper, stamps, and sealed joints were obtained without contact to the sample.

  16. Label-free imaging of cellular malformation using high resolution photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Zhongjiang; Li, Bingbing; Yang, Sihua

    2014-09-01

    A label-free high resolution photoacoustic microscopy (PAM) system for imaging cellular malformation is presented. The carbon fibers were used to testify the lateral resolution of the PAM. Currently, the lateral resolution is better than 2.7 μm. The human normal red blood cells (RBCs) were used to prove the imaging capability of the system, and a single red blood cell was mapped with high contrast. Moreover, the iron deficiency anemia RBCs were clearly distinguished from the cell morphology by using the PAM. The experimental results demonstrate that the photoacoustic microscopy system can accomplish label-free photoacoustic imaging and that it has clinical potential for use in the detection of erythrocytes and blood vessels malformation.

  17. Nonlinear imaging techniques as non-destructive, high-resolution diagnostic tools for cultural heritage studies

    NASA Astrophysics Data System (ADS)

    Filippidis, G.; Tserevelakis, G. J.; Selimis, A.; Fotakis, C.

    2015-02-01

    Here, we present a review of the implementation of nonlinear imaging microscopy techniques such as second and third harmonic generation (SHG-THG) and multi-photon excitation fluorescence (MPEF), as high-resolution, non-invasive diagnostic tools for cultural heritage studies. Specifically, the above nonlinear modalities are employed for the precise three-dimensional (3D) delineation of the protective layers bulk in model multilayer painting artworks. The high axial resolution thickness determination of protective layers through the use of THG imaging and the identification of the chemical composition of the artefacts via MPEF measurements are depicted. Furthermore, we reveal the potential of MPEF imaging measurements for the identification of the corrosion layers in silver-based artefacts. Finally, nonlinear modalities are employed for the assessment of the affected region and the obtainment of depth information during laser cleaning of polymeric coatings.

  18. Tip radius preservation for high resolution imaging in amplitude modulation atomic force microscopy

    SciTech Connect

    Ramos, Jorge R.

    2014-07-28

    The acquisition of high resolution images in atomic force microscopy (AFM) is correlated to the cantilever's tip shape, size, and imaging conditions. In this work, relative tip wear is quantified based on the evolution of a direct experimental observable in amplitude modulation atomic force microscopy, i.e., the critical amplitude. We further show that the scanning parameters required to guarantee a maximum compressive stress that is lower than the yield/fracture stress of the tip can be estimated via experimental observables. In both counts, the optimized parameters to acquire AFM images while preserving the tip are discussed. The results are validated experimentally by employing IgG antibodies as a model system.

  19. Ribbon scanning confocal for high-speed high-resolution volume imaging of brain

    PubMed Central

    Rose, Annika H.; Gibson, Gregory A.; Gardner, Christina L.; Sun, Chengqun; Reed, Douglas S.; Lam, L. K. Metthew; St. Croix, Claudette M.; Strick, Peter L.; Klimstra, William B.; Watkins, Simon C.

    2017-01-01

    Whole-brain imaging is becoming a fundamental means of experimental insight; however, achieving subcellular resolution imagery in a reasonable time window has not been possible. We describe the first application of multicolor ribbon scanning confocal methods to collect high-resolution volume images of chemically cleared brains. We demonstrate that ribbon scanning collects images over ten times faster than conventional high speed confocal systems but with equivalent spectral and spatial resolution. Further, using this technology, we reconstruct large volumes of mouse brain infected with encephalitic alphaviruses and demonstrate that regions of the brain with abundant viral replication were inaccessible to vascular perfusion. This reveals that the destruction or collapse of large regions of brain micro vasculature may contribute to the