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Sample records for infrared microscope based

  1. Infrared microscope inspection apparatus

    DOEpatents

    Forman, Steven E.; Caunt, James W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  2. Infrared microscope inspection apparatus

    DOEpatents

    Forman, S.E.; Caunt, J.W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface. 4 figs.

  3. Large scale infrared imaging of tissue micro arrays (TMAs) using a tunable Quantum Cascade Laser (QCL) based microscope.

    PubMed

    Bassan, Paul; Weida, Miles J; Rowlette, Jeremy; Gardner, Peter

    2014-08-21

    Chemical imaging in the field of vibrational spectroscopy is developing into a promising tool to complement digital histopathology. Applications include screening of biopsy tissue via automated recognition of tissue/cell type and disease state based on the chemical information from the spectrum. For integration into clinical practice, data acquisition needs to be speeded up to implement a rack based system where specimens are rapidly imaged to compete with current visible scanners where 100's of slides can be scanned overnight. Current Fourier transform infrared (FTIR) imaging with focal plane array (FPA) detectors are currently the state-of-the-art instrumentation for infrared absorption chemical imaging, however recent development in broadly tunable lasers in the mid-IR range is considered the most promising potential candidate for next generation microscopes. In this paper we test a prototype quantum cascade laser (QCL) based spectral imaging microscope with a focus on discrete frequency chemical imaging. We demonstrate how a protein chemical image of the amide I band (1655 cm(-1)) of a 2 × 2.4 cm(2) breast tissue microarray (TMA) containing over 200 cores can be measured in 9 min. This result indicates that applications requiring chemical images from a few key wavelengths would be ideally served by laser-based microscopes. PMID:24965124

  4. [Microscopic infrared spectral imaging of oily core].

    PubMed

    Huang, Qiao-Song; Yu, Zhao-Xian; Li, Jing; Chen, Chen

    2009-02-01

    In the present paper, the authors examined some oily core by microscopic infrared spectral imaging methods. Those methods can be classified in three modes, referred to as "transmission mode", "reflection mode" and "attenuated total reflection (ATR) mode". The observed oily core samples belong to siltstone. The samples were made of quartz (-20%), feldspar(-50%) and other rock (igneous rock 25%, metamorphic rocks 1%, sedimentary rock 4%); a little recrystallized calcite (-1%) was in the pore, and the argillaceous matter was distributed along the edge of a pore. The experimental work has been accomplished using SHIMADZU Model IRPrestige-21 Fourier transform infrared spectrophotometer plus AIM8800 infrared microscope. For IRPrestige-21, the spectral range is 7 800-350 cm(-1) spectral resolution is 1 cm(-1), and AIM8800 microscope with motorized stages has a resolution of 1 micrometer. The experiment was preformed at room temperature. In "transmission mode" infrared spectral imaging method, the spectral range was limited in wavenumbers greater than 2 000 cm(-1) because the base glass piece has strong light absorption. In contrast with "transmission mode", in "attenuated total reflection (ATR) mode", the depth of penetration into sample is very small (1-2 micrometer), then the absorbance value has nothing to do with base glass piece light absorption. In microscopic infrared transmission spectra, the experimental result shows that there are some strong absorption peaks at 2 866, 2 928, 3 618 and 2 515 cm(-1) respectively. The former two peaks correspond to methyl(methylene) symmetrical and unsymmetrical stretch vibration mode, respectively. The latter two peaks correspond to hydroxyl-stretch vibration mode and S-H, P-H chemical bond stretch vibration mode, respectively. In microscopic longwave infrared ATR spectra, there are other stronger absorption peaks at 1 400, 1 038 and 783 cm(i1)respectively, corresponding to methyl(methylene) widing vibration mode and optical mode

  5. Development of a scanning near-field infrared microscope based on a free electron laser

    SciTech Connect

    Hong, M.K.; Erramilli, S.; Jeung, A.

    1995-12-31

    Infrared spectroscopy is one of the most sensitive technique available for identifying and characterizing organic materials. Most molecules exhibit a large number of well-resolved strongly absorbing spectral lines in the mid-IR region of the spectrum. In addition to our own efforts described last year, Creuzet et al have also been working on combining infrared spectroscopy with sub-micron spatial resolution imaging. Scanning Near Field Infrared Microscopy (SNIM) when combined with high brightness tunable FEL radiation, provides a powerful new research tool. We have developed two new probes for use in SNIM. The first are chalcogenide fibers capable of transmitting images in the 2-12 {mu} range. At the Stanford picosecond Free Electron Laser, we have successfully obtained images of metal surfaces and of collagen fibers on diamond at a wavelength of 5.01 {mu}, with a nominal spatial resolution of 0.5 {mu} demonstrating that near field imaging can be obtained on biological samples. At a wavelength of 6.3{mu}, we found that the chalcogenide fibers are limited in their ability to withstand high powers, most likely because of the presence of absorption bands in the polyimide coating used to sheath the brittle fibers. In collaboration with Prof J. Harrington (Rutgers University), we have also developed hollow glass capillaries with metal coated on the inside. These probes are able to withstand significantly higher powers, and can function to longer wavelengths, out into the Far IR region.

  6. [Authentication of Trace Material Evidence in Forensic Science Field with Infrared Microscopic Technique].

    PubMed

    Jiang, Zhi-quan; Hu, Ke-liang

    2016-03-01

    In the field of forensic science, conventional infrared spectral analysis technique is usually unable to meet the detection requirements, because only very a few trace material evidence with diverse shapes and complex compositions, can be extracted from the crime scene. Infrared microscopic technique is developed based on a combination of Fourier-transform infrared spectroscopic technique and microscopic technique. Infrared microscopic technique has a lot of advantages over conventional infrared spectroscopic technique, such as high detection sensitivity, micro-area analysisand nondestructive examination. It has effectively solved the problem of authentication of trace material evidence in the field of forensic science. Additionally, almost no external interference is introduced during measurements by infrared microscopic technique. It can satisfy the special need that the trace material evidence must be reserved for witness in court. It is illustrated in detail through real case analysis in this experimental center that, infrared microscopic technique has advantages in authentication of trace material evidence in forensic science field. In this paper, the vibration features in infrared spectra of material evidences, including paints, plastics, rubbers, fibers, drugs and toxicants, can be comparatively analyzed by means of infrared microscopic technique, in an attempt to provide powerful spectroscopic evidence for qualitative diagnosis of various criminal and traffic accident cases. The experimental results clearly suggest that infrared microscopic technique has an incomparable advantage and it has become an effective method for authentication of trace material evidence in the field of forensic science. PMID:27400510

  7. Microscopic spectral imaging using mid-infrared semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Guo, Bujin-.; Wang, Yi; Peng, Chuan; Luo, Guipeng; Le, Han Q.

    2003-07-01

    Infrared micro-spectroscopy is a useful tool for basic research and biomedical applications. Conventional microspectroscopic imaging apparatuses use thermal sources for sample illumination, which have low brightness, low optical spectral intensity, and high noise. This work evaluates the system engineering advantages of using mid-infrared semiconductor lasers that offer orders-of magnitude higher brightness, spectral intensity, and lower noise. A laser-based microscopic spectral imaging system with focal plane array detectors demonstrated a high signal-to-noise ratio (>20 dB) at video frame rate for a large illuminated area. Microscopic spectral imaging with fixed-wavelength and tunable lasers of 4.6, 6, and 9.3-μm wavelength was applied to a number of representative samples that consist of biological tissues (plant and animal) and solid material (a stack of laminated polymers). Transmission spectral images with ~30-dB dynamic range were obtained with clear evidence of spectral features for different samples. The potential of more advanced systems with a wide coverage of spectral bands is discussed.

  8. Forensic applications of microscopical infrared internal reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Tungol, Mary W.; Bartick, Edward G.; Reffner, John A.

    1994-01-01

    Applications of microscopical infrared internal reflection spectroscopy in forensic science are discussed. Internal reflection spectra of single fibers, hairs, paint chips, vehicle rubber bumpers, photocopy toners, carbon copies, writing ink on paper, lipstick on tissue, black electrical tape, and other types of forensic evidence have been obtained. The technique is convenient, non-destructive, and may permit smeared materials to be analyzed in situ.

  9. Foldscope: Origami-Based Paper Microscope

    PubMed Central

    Cybulski, James S.; Clements, James; Prakash, Manu

    2014-01-01

    Here we describe an ultra-low-cost origami-based approach for large-scale manufacturing of microscopes, specifically demonstrating brightfield, darkfield, and fluorescence microscopes. Merging principles of optical design with origami enables high-volume fabrication of microscopes from 2D media. Flexure mechanisms created via folding enable a flat compact design. Structural loops in folded paper provide kinematic constraints as a means for passive self-alignment. This light, rugged instrument can survive harsh field conditions while providing a diversity of imaging capabilities, thus serving wide-ranging applications for cost-effective, portable microscopes in science and education. PMID:24940755

  10. Ground based infrared astronomy

    NASA Technical Reports Server (NTRS)

    Jennings, D. E.

    1988-01-01

    Infrared spectroscopic instrumentation has been developed for ground-based measurements of astrophysical objects in the intermediate infrared. A conventional Michelson interferometer is limited for astronomical applications in the intermediate infrared by quantum noise fluctuations in the radiation form the source and/or background incident on the detector, and the multiplex advantage is no longer available. One feasible approach to recovering the multiplex advantage is post-dispersion. The infrared signal after passing through telescope and interferometer, is dispersed by a low resolution grating spectrometer onto an array of detectors. The feasibility of the post-dispersion system has been demonstrated with observations of astrophysical objects in the 5 and 10 micrometer atmospheric windows from ground-based telescopes. During FY87/88 the post-disperser was used at the Kitt Peak 4-meter telescope and McMath telescope with facility Fourier transform spectrometers. Jupiter, Saturn, Mars, and Venus were observed. On Jupiter, the resolution at 12 micrometer was 0.01/cm, considerably higher than had been acheived previously. The spectrum contains Jovian ethane and acetylene emission. Construction was begun on the large cryogenic grating spectrometer.

  11. Versatile multispectral microscope based on light emitting diodes

    NASA Astrophysics Data System (ADS)

    Brydegaard, Mikkel; Merdasa, Aboma; Jayaweera, Hiran; Ålebring, Jens; Svanberg, Sune

    2011-12-01

    We describe the development of a novel multispectral microscope, based on light-emitting diodes, capable of acquiring megapixel images in thirteen spectral bands from the ultraviolet to the near infrared. The system captures images and spectra in transmittance, reflectance, and scattering modes. We present as examples of applications ground truth measurements for remote sensing and parasitology diagnostics. The system is a general purpose scientific instrument that could be used to develop dedicated simplified instruments with optimal bands and mode selection.

  12. Chemical imaging of cotton fibers using an infrared microscope and a focal-plane array detector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this presentation, the chemical imaging of cotton fibers with an infrared microscope and a Focal-Plane Array (FPA) detector will be discussed. Infrared spectroscopy can provide us with information on the structure and quality of cotton fibers. In addition, FPA detectors allow for simultaneous spe...

  13. Atomic force microscope infrared spectroscopy of griseofulvin nanocrystals

    PubMed Central

    Harrison, A. J.; Bilgili, E. A.; Beaudoin, S. P.

    2013-01-01

    The goal of this work was to evaluate the ability of photothermal induced resonance (PTIR) to measure the local infrared absorption spectra of crystalline organic drug nanoparticles embedded within solid matrices. Herein, the first reports of the chemical characterization of sub-100 nm organic crystals are described; infrared spectra of 90 nm griseofulvin particles were obtained, confirming the chemical resolution of PTIR beyond the diffraction limit. Additionally, particle size distributions via dynamic light scattering and PTIR image analysis were found to be similar, suggesting that the PTIR measurements are not significantly affected by inhomogeneous infrared absorptivity of this system. Thus as medical applications increasingly emphasize localized drug delivery via micro/nano-engineered structures, PTIR can be used to unambiguously chemically characterize drug formulations at these length scales. PMID:24171582

  14. Atomic force microscope infrared spectroscopy of griseofulvin nanocrystals.

    PubMed

    Harrison, Aaron J; Bilgili, Ecevit A; Beaudoin, Stephen P; Taylor, Lynne S

    2013-12-01

    The goal of this work was to evaluate the ability of photothermal-induced resonance (PTIR) to measure the local infrared absorption spectra of crystalline organic drug nanoparticles embedded within solid matrices. Herein, the first reports of the chemical characterization of sub-100 nm organic crystals are described; infrared spectra of 90 nm griseofulvin particles were obtained, confirming the chemical resolution of PTIR beyond the diffraction limit. Additionally, particle size distributions via dynamic light scattering and PTIR image analysis were found to be similar, suggesting that the PTIR measurements are not significantly affected by inhomogeneous infrared absorptivity of this system. Thus as medical applications increasingly emphasize localized drug delivery via micro/nanoengineered structures, PTIR can be used to unambiguously chemically characterize drug formulations at these length scales. PMID:24171582

  15. Universal tool microscope remanufacture based on CCD

    NASA Astrophysics Data System (ADS)

    Kang, Jian; Hu, Zhongxiang; Zhang, Xunming; Zhang, Jiaying

    2006-02-01

    To overcome the drawback of traditional universal tool microscopes, a remanufacturing scheme based on charge coupled devices (CCD) is proposed. In this paper, the remanufacturing of old tool microscopes is replaced gradually by CCD and grating ruler and the development of a novel measuring system designed to directly analyze image of the screw to be measured is discussed. For the analysis of image, such novel image processing methods as adaptive switching median (ASM) filter and edge detection based on the modified Sobel operator are designed. For the line detection algorithm, HOUGH transform also is used to measure the screw parameter. Experiments on screw images demonstrate that the scheme of remanufactured universal tool microscope is of feasibility and the proposed measurement is of validity.

  16. Laser scan microscope and infrared laser scan microcope: two important tools for device testing

    NASA Astrophysics Data System (ADS)

    Ziegler, Eberhard

    1991-03-01

    The optical beam induced current (OBIC) produced in devices by a laser scan microscope (LSM) is used to localize hot spots, leakage currents, electrostatic discharge defects and weak points. The LSM also allows photoluminescence measurements with high spatial and energy resolution. Using the infrared laser scan microscope (IR LSM), defects in the metallization and latch-up sensitive region could be detected from the back of the device.

  17. Detection and measurement of electroreflectance on quantum cascade laser device using Fourier transform infrared microscope

    SciTech Connect

    Enobio, Eli Christopher I.; Ohtani, Keita; Ohno, Yuzo; Ohno, Hideo

    2013-12-02

    We demonstrate the use of a Fourier Transform Infrared microscope system to detect and measure electroreflectance (ER) from mid-infrared quantum cascade laser (QCL) device. To characterize intersubband transition (ISBT) energies in a functioning QCL device, a microscope is used to focus the probe on the QCL cleaved mirror. The measured ER spectra exhibit resonance features associated to ISBTs under applied electric field in agreement with the numerical calculations and comparable to observed photocurrent, and emission peaks. The method demonstrates the potential as a characterization tool for QCL devices.

  18. A passive long-wavelength infrared microscope with a highly sensitive phototransistor.

    PubMed

    Kajihara, Yusuke; Komiyama, Susumu; Nickels, Patrick; Ueda, Takeji

    2009-06-01

    A passive scanning confocal microscope in the long-wavelength infrared (LWIR) region has been developed for sensitive imaging of spontaneous LWIR radiation by utilizing an ultrahighly sensitive detector, called the charge-sensitive infrared phototransistor (CSIP). The microscope consisted of room-temperature components including a Ge objective lens and liquid helium temperature components including a confocal pinhole, Ge relay lenses, and CSIP detector. With the microscope, thermal radiation (wavelength of 14.7 microm) spontaneously emitted by the object was studied with a spatial resolution of 25 microm. Clear passive LWIR imaging pictures were obtained by scanning a sample consisting of glass, Al foil, Ag paste, and Au. Clear passive LWIR image was also obtained even when the sample surface was covered by a GaAs or Si plate. This work suggests usefulness of CSIP detectors for application of passive LWIR microscopy. PMID:19566205

  19. Optical microscopic imaging based on VRML language

    NASA Astrophysics Data System (ADS)

    Zhang, Xuedian; Zhang, Zhenyi; Sun, Jun

    2009-11-01

    As so-called VRML (Virtual Reality Modeling Language), is a kind of language used to establish a model of the real world or a colorful world made by people. As in international standard, VRML is the main kind of program language based on the "www" net building, which is defined by ISO, the kind of MIME is x-world or x-VRML. The most important is that it has no relationship with the operating system. Otherwise, because of the birth of VRML 2.0, its ability of describing the dynamic condition gets better, and the interaction of the internet evolved too. The use of VRML will bring a revolutionary change of confocal microscope. For example, we could send different kinds of swatch in virtual 3D style to the net. On the other hand, scientists in different countries could use the same microscope in the same time to watch the same samples by the internet. The mode of sending original data in the model of text has many advantages, such as: the faster transporting, the fewer data, the more convenient updating and fewer errors. In the following words we shall discuss the basic elements of using VRML in the field of Optical Microscopic imaging.

  20. Infrared Detection of Evidence for Microscopic Organisms on Europa

    NASA Astrophysics Data System (ADS)

    Dalton, J. B.; Mogul, R.

    2002-12-01

    The infrared detection of evidence for microorganisms on surfaces of icy satellites requires four conditions: (1) the emplacement of microorganisms at the surface, (2) the survival of biotic material in the hostile conditions of space, (3) that the biotic material exhibit diagnostic infrared absorption features and (4) spectra with sufficient resolution and signal-to-noise ratios. This paper will focus on each topic with respect to cryogenic data recently collected on model microorganisms. Several studies suggest that materials from a Europan interior ocean have been emplaced in disrupted regions[1-10]. If the Europan ocean at one time contained Life and its associated biomolecules, then it is possible that surface materials may still harbor some remnant of these structures. Such remnant material must be capable of surviving the low pressure, low temperature and high radiation environment. The terrestrial extremophile Deinococcus radiodurans has been found viable after exposure both to vacuum at temperatures as low as 80 K [11] and to 60 Gy/h of radiation[12]. The chemical degradation of D. radiodurans has also been shown to be dependent on plasma composition (O2 {>>} CO2)[13]. Hence, it is reasonable to assume that some degree of sterilization and degradation would be occurring at the surface of Europa. However, given the sputtering rate at Europa of approximately a few cm every few million years [14], it is possible that fresh material may be continually exposed from depths to which little radiation penetrates. Remote sensing of the surface, therefore, would not be dependent on the survival of the microorganism but on the endurance of the particular biomolecules that give rise to the spectral signature. This endurance is not unreasonable since previous studies have detected hydrated salts, which contain labile bonds to water, on Europa [3,15]. Cryogenic reflectance spectra of hydrated sulfate salts have broad (150-300 nm), asymmetric absorption features due to

  1. Infrared astronomical data base and catalog of infrared observations

    NASA Technical Reports Server (NTRS)

    Schmitz, M.; Gezari, D. Y.; Mead, J. M.

    1981-01-01

    The NASA/Goddard Space Flight Center has developed a computer data base of infrared astronomical observations. The data base represents a machine-readable library of infrared observational data published in the relevant literature since 1960 for celestial sources outside the solar system. It likewise includes the contents of infrared surveys and catalogs. A catalog of infrared observations has been developed in both printed and magnetic-tape formats. The data base will be accessed through a bibliographic guide and an atlas of infrared source names and positions. Future plans also include two-dimensional graphical displays of infrared data and a user-interactive data terminal.

  2. Plasmonic spectra of individual subwavelength particles under the infrared microscope: cells and airborne dust

    NASA Astrophysics Data System (ADS)

    Coe, James V.; Lioi, David B.; Shaffer, Lindsey; Malone, Marvin A.; Luthra, Antriksh; Ravi, Aruna

    2014-03-01

    A plasmonic metal film with a subwavelength hole array (a mesh) is used to capture an individual subwavelength particle, like a single yeast cell or airborne dust particle, and an imaging infrared (IR) microscope, records a scatterfree, IR absorption spectrum of the particle. Individual spectra of wavelength scale particles usually suffer from large scattering effects. This paper starts by demonstrating the plasmonic nature of the mesh in the infrared, proceeds to how this special form of light (surface plasmon polariton mediated transmission resonance) leads to scatter-free IR absorption spectra of individual, subwavelength particles, and ends with work on yeast cells and dust particles from our laboratory air and a household filter.

  3. Inquiry based learning with a virtual microscope

    NASA Astrophysics Data System (ADS)

    Kelley, S. P.; Sharples, M.; Tindle, A.; Villasclaras-Fernández, E.

    2012-12-01

    As part of newly funded initiative, the Wolfson OpenScience Laboratory, we are linking a tool for inquiry based learning, nQuire (http://www.nquire.org.uk) with the virtual microscope for Earth science (http://www.virtualmicroscope.co.uk) to allow students to undertake projects and gain from inquiry based study thin sections of rocks without the need for a laboratory with expensive petrological microscopes. The Virtual Microscope (VM) was developed for undergraduate teaching of petrology and geoscience, allowing students to explore rock hand specimens and thin sections in a browser window. The system is based on HTML5 application and allows students to scan and zoom the rocks in a browser window, view in ppl and xpl conditions, and rotate specific areas to view birefringence and pleochroism. Importantly the VM allows students to gain access to rare specimens such as Moon rocks that might be too precious to suffer loss or damage. Experimentation with such specimens can inspire the learners' interest in science and allows them to investigate relevant science questions. Yet it is challenging for learners to engage in scientific processes, as they may lack scientific investigation skills or have problems in planning their activities; for teachers, managing inquiry activities is a demanding task (Quintana et al., 2004). To facilitate the realization of inquiry activities, the VM is being integrated with the nQuire tool. nQuire is a web tool that guides and supports students through the inquiry process (Mulholland et al., 2011). Learners are encouraged to construct their own personally relevant hypothesis, pose scientific questions, and plan the method to answer them. Then, the system enables users to collect and analyze data, and share their conclusions. Teachers can monitor their students' progress through inquiries, and give them access to new parts of inquiries as they advance. By means of the integration of nQuire and the VM, inquiries that involve collecting data

  4. Real-time quantum cascade laser-based infrared microspectroscopy in-vivo

    NASA Astrophysics Data System (ADS)

    Kröger-Lui, N.; Haase, K.; Pucci, A.; Schönhals, A.; Petrich, W.

    2016-03-01

    Infrared microscopy can be performed to observe dynamic processes on a microscopic scale. Fourier-transform infrared spectroscopy-based microscopes are bound to limitations regarding time resolution, which hampers their potential for imaging fast moving systems. In this manuscript we present a quantum cascade laser-based infrared microscope which overcomes these limitations and readily achieves standard video frame rates. The capabilities of our setup are demonstrated by observing dynamical processes at their specific time scales: fermentation, slow moving Amoeba Proteus and fast moving Caenorhabditis elegans. Mid-infrared sampling rates between 30 min and 20 ms are demonstrated.

  5. Examination of cotton fibers and common contaminants using an infrared microscope and a focal-plane array detector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chemical imaging of cotton fibers and common contaminants in fibers is presented. Chemical imaging was performed with an infrared microscope equipped with a Focal-Plane Array (FPA) detector. Infrared spectroscopy can provide us with information on the structure and quality of cotton fibers. In a...

  6. Infrared astronomical data base and catalog of infrared observations

    NASA Technical Reports Server (NTRS)

    Schmitz, M.; Gezari, D. Y.; Mead, J. M.

    1982-01-01

    A computer data base of infrared astronomical observations has been established at NASA/Goddard Space Flight Center. It contains a summary of all infrared (1-100 microns) observations of celestial sources outside the solar system, published in the major scientific journals since 1960, as well as the contents of infrared surveys and catalogs. A Catalog of Infrared Observations (CIO) has been developed from the data base in printed and magnetic tape versions. A bibliographic Guide to the Infrared Astronomical Literature, and an Altas of Infrared Source Names and Positions will be published in conjunction with the catalog. Future plans include development of an interactive data system at Goddard which will give a user direct access to the computerized data.

  7. Wave-Based Inversion & Imaging for the Optical Quadrature Microscope

    SciTech Connect

    Lehman, S K

    2005-10-27

    The Center for Subsurface Sensing & Imaging System's (CenSSIS) Optical Quadrature Microscope (OQM) is a narrow band visible light microscope capable of measuring both amplitude and phase of a scattered field. We develop a diffraction tomography, that is, wave-based, scattered field inversion and imaging algorithm, for reconstructing the refractive index of the scattering object.

  8. Portable, X-Y translating, infrared microscope for remote inspection of photovoltaic solar arrays

    SciTech Connect

    Forman, S.E.; Caunt, J.W.

    1980-01-01

    The prevalent physical defect found in terrestrial photovoltaic modules during manufacture and field exposure has been the cracked solar cell. Cells can become cracked during handling, because of thermal mismatch in their encapsulation packages, or due to environmental phenomena such as hail. A device is described which can be used remotely to locate cracked silicon solar cells in photovoltaic modules. This solar-cell inspection device can be used either in the laboratory for quality assurance and failure analysis evaluation or at array fields to monitor cracked-cell occurrence. It consists of: (a) an infrared microscope that operates at 1.0 micron, uses darkfield illumination, has a relatively large field of view (3.0 in.), has low system magnification (5X to 15X), and has a video display output; (b) a portable X-Y translator that is capable of moving the microscope over an 8 ft. x 8 ft. area; and (c) a console that allows remote instrument control and visual inspection of modules or arrays (up to 500 ft). This system presently is undergoing laboratory and field testing as part of the DOE-sponsored MIT Lincoln Laboratory Solar Photovoltiac Residential Project.

  9. A mirror based scheme of a laser projection microscope

    NASA Astrophysics Data System (ADS)

    Gubarev, F. A.; Li, Lin; Klenovskii, M. S.

    2016-04-01

    The paper discusses the design of a laser projection microscope with a mirror-based scheme of image formation. It is shown that the laser projection microscope with the mirror-based scheme of image formation is well suited for distant objects monitoring. This scheme allowed obtaining a field of view of more than 3 cm at the distance of 4 m from the brightness amplifier

  10. Infrared microscopic investigation of skin biopsies after application of implant material for correction of aesthetic deficiencies

    NASA Astrophysics Data System (ADS)

    Heise, H. M.; Seifert, L.; Kuckuk, R.; Lenzen, C.

    2003-06-01

    Different implant materials are currently applied for correction of inborn and acquired aesthetic deficiencies of the human skin. Several commercial products are used as dermal fillers for aesthetic facial surgery, which contain bovine collagen and cross-linked substances, or hyaluronic acid derivatives, both also in combination with polymethylmethacrylate or co-polymerisates of methacrylate derivatives. Gels containing polylactate or dimethylpolysiloxane were also available. Infrared spectra of such products are presented after dry film preparation. Infrared microscopy using attenuated total reflection was employed to identify previously applied dermal filler products in excised tissue without embedding the sample in a matrix material such as paraffin as needed for microtoming. Several tissue spots guided by inspecting the different color grades were found with increased single implant component concentrations, as supported by the dominating spectral features and difference spectroscopy. The chemistry within dermal biopsies after material implantation can be uniquely investigated based on their infrared spectra.

  11. Multi-perspective scanning microscope based on Talbot effect

    NASA Astrophysics Data System (ADS)

    Sun, Yangyang; Pang, Shuo

    2016-01-01

    We report a multi-perspective scanning microscope based on the Talbot effect of a periodic focal spot array. Talbot illumination decouples the lateral scanning and the focal spots tuning. Large field of view fluorescence Talbot Microscope has been demonstrated by globally changing the incident wavefront gradient. Here, we explore the design freedom of adjusting the wavefront locally within each period and thus engineer the point spread function of the focal spots. We demonstrate an imaging system capable of reconstructing multi-perspective microscopic images in both bright field and fluorescence mode. With the multi-perspective imaging capability, we envision a more robust microscopic imaging system for large field of view fluorescence microscopy applications. This method is also suitable for compact imaging systems for multi-layer microfluidic systems.

  12. Characterization of Lunar Soils Using a Thermal Infrared Microscopic Spectral Imaging System

    NASA Astrophysics Data System (ADS)

    Crites, S. T.; Lucey, P. G.

    2010-12-01

    Lunar Reconnaissance Orbiter's Diviner radiometer has provided the planetary science community with a large amount of thermal infrared spectral data. This data set offers rich opportunities for lunar science, but interpretation of the data is complicated by the limited data on lunar materials. While spectra of pure terrestrial minerals have been used effectively for Mars applications, lunar minerals and glasses have been affected by space weathering processes that may alter their spectral properties in important ways. For example, mineral grains acquire vapor deposited coatings, and agglutinate glass contains abundant nanophase iron as a result of exposure to the space environment. Producing mineral separates in sufficient quantities (at least tens of mg) for spectral characterization is painstaking, time consuming and labor intensive; as an alternative we have altered an infrared hyperspectral imaging system developed for remote sensing under funding from the Planetary Instrument Definition and Development program (PIDDP) to enable resolved microscopic spectral imaging. The concept is to characterize the spectral properties of individual grains in lunar soils, enabling a wide range of spectral behaviors of components to be measured rapidly. The instrument, sensitive from 8 to 15 microns at 15 wavenumber resolution, images a field of view of 8 millimeters at 30 micron resolution and scans at a rate of about 1 mm/second enabling relatively large areas to be scanned rapidly. Our experiments thus far use a wet-sieved 90-150 um size fraction with the samples arrayed on a heated substrate in a single layer in order to prevent spectral interactions between grains. We have begun with pure mineral separates, and unsurprisingly we find that the individual mineral grain emission spectra of a wide range of silicates are very similar to spectra of coarse grained powders. We have begun to obtain preliminary data on lunar soils as well. We plan to continue imaging of lunar soils

  13. Development of a DMD-based fluorescence microscope

    NASA Astrophysics Data System (ADS)

    Chakrova, Nadya; Rieger, Bernd; Stallinga, Sjoerd

    2015-03-01

    We present a versatile fluorescence microscope, built by complementing a conventional fluorescence microscope with a digital micro-mirror device (DMD) in the illumination path. Arbitrary patterns can be created on the DMD and projected onto the sample. This patterned illumination can be used to improve lateral and axial resolution over the resolution of a wide-field microscope, as well as to reduce the illumination dose. Different illumination patterns require different reconstruction strategies and result in an image quality similar to confocal or structured illumination microscopy. We focus on the optical design and characterization of a DMD-based microscope. Estimation of the optical quality of the microscope has been carried out by measuring the modulation transfer function from edge profiles. We have obtained optically sectioned images by applying multi-spot illumination patterns followed by digital pinholing. The sectioning capabilities of our DMD-based microscope were estimated from the dependence of the signal-to-background and signalto-noise ratios on the pitch of the projected multi-spot patterns and the size of the digital pinhole. In addition, we provide an outlook on the use of pseudo-random illumination patterns for achieving both sectioning and resolution enhancement.

  14. Cantilever based optical interfacial force microscope

    NASA Astrophysics Data System (ADS)

    Bonander, Jeremy R.; Kim, Byung I.

    2008-03-01

    We developed a cantilever based optical interfacial force microscopy (COIFM) that employs a microactuated silicon cantilever and optical detection method to establish the measurement of the single molecular interactions using the force feedback technique. Through the direct measurement of the COIFM force-distance curves, we have demonstrated that the COIFM is capable of unveiling structural and mechanical information on interfacial water at the single molecular level over all distances between two hydrophilic surfaces.

  15. Submicrometer infrared surface imaging using a scanning-probe microscope and an optical parametric oscillator laser.

    PubMed

    Hill, Graeme A; Rice, James H; Meech, Stephen R; Craig, Duncan Q M; Kuo, Paulina; Vodopyanov, Konstantin; Reading, Michael

    2009-02-15

    Submicrometer IR surface imaging was performed with a resolution better than the diffraction limit. The apparatus was based on an IR optical parametric oscillator laser and a commercial atomic force microscope and used, as the detection mechanism, induced resonant oscillations in an atomic force microscopy (AFM) cantilever. For the first time to our knowledge this was achieved with top-down illumination and a benchtop IR source, thus extending the range of potential applications of this technique. IR absorption and AFM topography images of polystyrene beads were recorded simultaneously with an image resolution of 200 nm. PMID:19373331

  16. DoFP polarimeter based polarization microscope for biomedical applications

    NASA Astrophysics Data System (ADS)

    Chang, Jintao; He, Honghui; He, Chao; Ma, Hui

    2016-03-01

    Polarization microscope is a useful technique to observe the optical anisotropic nature of biomedical specimens and provide more microstructural information than the conventional microscope. In this paper, we present a division of focal plane (DoFP) polarimeter based polarization microscope which is capable of imaging both the Stokes vector and the 3×4 Mueller matrix. The Mueller matrix measurement can help us completely understand the polarization properties of the sample and the Stokes vector measurement is a simultaneous technology. First, we calibrate a DoFP polarimeter using the polarization data reduction method for accurate Stokes vector measurements. Second, as the Stokes vector computation for all pixels using the calibrated instrument matrix is usually time consuming, we develop a GPU acceleration algorithm for real time Stokes vector calculations. Third, based on the accurate and fast Stokes vector calculation, we present an optimal 4-states of polarization (4-SoP) illumination scheme for Mueller matrix measurement using the DoFP polarimeter. Finally, we demonstrate the biomedical applications of the DoFP polarimeter based polarization microscope. Experiment results show that the characteristic features of many biomedical samples can be observed in the "polarization staining" images using the circularly polarized light as illumination. In this way, combined with GPU acceleration algorithm, the DoFP polarization microscope has the capacity for real time polarization monitoring of dynamic processes in biological samples.

  17. Near-field microscope probe for far infrared time domain measurements

    NASA Astrophysics Data System (ADS)

    Mitrofanov, O.; Brener, I.; Wanke, M. C.; Ruel, R. R.; Wynn, J. D.; Bruce, A. J.; Federici, J.

    2000-07-01

    A near-field probe fabrication technique for far-infrared frequencies based on photoconducting antennas is developed. A subwavelength-size field source is accomplished by means of an aperture and protruding high refractive index tip. The near-field probe is tested by using free space traveling electromagnetic pulses with a broadband spectrum in the range of 0.3-1.5 THz. A spatial resolution of 60 μm is achieved for a 50 μm aperture. The described probe may be used for near-field transmission microscopy in illumination and collection modes. Resolution may be further improved by means of a smaller aperture.

  18. Microscopic emission and reflectance thermal infrared spectroscopy: instrumentation for quantitative in situ mineralogy of complex planetary surfaces.

    PubMed

    Edwards, C S; Christensen, P R

    2013-04-10

    The diversity of investigations of planetary surfaces, especially Mars, using in situ instrumentation over the last decade is unprecedented in the exploration history of our solar system. The style of instrumentation that landed spacecraft can support is dependent on several parameters, including mass, power consumption, instrument complexity, cost, and desired measurement type (e.g., chemistry, mineralogy, petrology, morphology, etc.), all of which must be evaluated when deciding an appropriate spacecraft payload. We present a laboratory technique for a microscopic emission and reflectance spectrometer for the analysis of martian analog materials as a strong candidate for the next generation of in situ instruments designed to definitively assess sample mineralogy and petrology while preserving geologic context. We discuss the instrument capabilities, signal and noise, and overall system performance. We evaluate the ability of this instrument to quantitatively determine sample mineralogy, including bulk mineral abundances. This capability is greatly enhanced. Whereas the number of mineral components observed from existing emission spectrometers is high (often >5 to 10 depending on the number of accessory and alteration phases present), the number of mineral components at any microscopic measurement spot is low (typically <2 to 3). Since this style of instrument is based on a long heritage of thermal infrared emission spectrometers sent to orbit (the thermal emission spectrometer), sent to planetary surfaces [the mini-thermal emission spectrometers (mini-TES)], and evaluated in laboratory environments (e.g., the Arizona State University emission spectrometer laboratory), direct comparisons to existing data are uniquely possible with this style of instrument. The ability to obtain bulk mineralogy and atmospheric data, much in the same manner as the mini-TESs, is of significant additional value and maintains the long history of atmospheric monitoring for Mars

  19. Infrared target recognition based on improved joint local ternary pattern

    NASA Astrophysics Data System (ADS)

    Sun, Junding; Wu, Xiaosheng

    2016-05-01

    This paper presents a simple, efficient, yet robust approach, named joint orthogonal combination of local ternary pattern, for automatic forward-looking infrared target recognition. It gives more advantages to describe the macroscopic textures and microscopic textures by fusing variety of scales than the traditional LBP-based methods. In addition, it can effectively reduce the feature dimensionality. Further, the rotation invariant and uniform scheme, the robust LTP, and soft concave-convex partition are introduced to enhance its discriminative power. Experimental results demonstrate that the proposed method can achieve competitive results compared with the state-of-the-art methods.

  20. Single-channel stereoscopic ophthalmology microscope based on TRD

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Lee, Sangyeob; Ha, Myungjin; Yu, Sungkon; Jang, Seulki; Jung, Byungjo

    2016-03-01

    A stereoscopic imaging modality was developed for the application of ophthalmology surgical microscopes. A previous study has already introduced a single-channel stereoscopic video imaging modality based on a transparent rotating deflector (SSVIM-TRD), in which two different view angles, image disparity, are generated by imaging through a transparent rotating deflector (TRD) mounted on a stepping motor and is placed in a lens system. In this case, the image disparity is a function of the refractive index and the rotation angle of TRD. Real-time single-channel stereoscopic ophthalmology microscope (SSOM) based on the TRD is improved by real-time controlling and programming, imaging speed, and illumination method. Image quality assessments were performed to investigate images quality and stability during the TRD operation. Results presented little significant difference in image quality in terms of stability of structural similarity (SSIM). A subjective analysis was performed with 15 blinded observers to evaluate the depth perception improvement and presented significant improvement in the depth perception capability. Along with all evaluation results, preliminary results of rabbit eye imaging presented that the SSOM could be utilized as an ophthalmic operating microscopes to overcome some of the limitations of conventional ones.

  1. Mosaicing of optical microscope imagery based on visual information.

    PubMed

    Carozza, Ludovico; Bevilacqua, Alessandro; Piccinini, Filippo

    2011-01-01

    Tools for high-throughput high-content image analysis can simplify and expedite different stages of biological experiments, by processing and combining different information taken at different time and in different areas of the culture. Among the most important in this field, image mosaicing methods provide the researcher with a global view of the biological sample in a unique image. Current approaches rely on known motorized x-y stage offsets and work in batch mode, thus jeopardizing the interaction between the microscopic system and the researcher during the investigation of the cell culture. In this work we present an approach for mosaicing of optical microscope imagery, based on local image registration and exploiting visual information only. To our knowledge, this is the first approach suitable to work on-line with non-motorized microscopes. To assess our method, the quality of resulting mosaics is quantitatively evaluated through on-purpose image metrics. Experimental results show the importance of model selection issues and confirm the soundness of our approach. PMID:22255746

  2. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-11-10

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  3. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-06-29

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  4. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-07-13

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  5. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-10-27

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  6. Spin microscope based on optically detected magnetic resonance

    DOEpatents

    Berman, Gennady P.; Chernobrod, Boris M.

    2007-12-11

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  7. Biomimetic, polymer-based microcantilever infrared sensors

    NASA Astrophysics Data System (ADS)

    Mueller, Michael Thomas

    This dissertation describes the initial development of a polymer-based, microcantilever infrared sensor. The development of the sensor is bio-inspired and based upon the long-range infrared sensor found in the pyrophilous jewel beetle Melanophila acuminata, which is able to seek out forest fires from more than 50 km away. Based on several proposed models of the infrared detector found in Melanophila acuminata, as well as published in vivo experiments, the feasibility of polymer-based infrared thermal sensors was explored and developed. Polymer materials were chosen due to their high absorptivity in the infrared range due to vibrational resonance modes characteristic of their organic bonds. Polymeric materials investigated in the course of this work include the polysaccharide and biomaterial chitin, its deacetylated derivative, chitosan, and the work-horse polymer of the semiconductor industry, novolak-resin-based photoresist. Chitin and chitosan are particularly noteworthy polymers for exploration in infrared detection due to their natural absorbance of infrared radiation near the 3 mum and 10 mum bands, which are important for the detection of the temperatures of warm engines and human body temperature, respectively. Because only limited work (primarily focused on electrodeposition) has been focused on the microscale patterning of chitosan, a photolithography process for chitosan and chitin was developed to allow the integration of the material into a variety of microelectromechanical systems processes. In addition to optical/infrared sensing, this process has a variety of potential applications in tissue engineering, protein engineering, and lab-on-a-chip devices. To demonstrate these areas of use, surface functionalization was demonstrated using bioconjugation to attach a protein to a patterned chitosan surface. Thin films of chitosan and chitin were characterized using laser profilometry to identify the effect of temperature on the film stress, and contact

  8. Design of high-performance adaptive objective lens with large optical depth scanning range for ultrabroad near infrared microscopic imaging

    PubMed Central

    Lan, Gongpu; Mauger, Thomas F.; Li, Guoqiang

    2015-01-01

    We report on the theory and design of adaptive objective lens for ultra broadband near infrared light imaging with large dynamic optical depth scanning range by using an embedded tunable lens, which can find wide applications in deep tissue biomedical imaging systems, such as confocal microscope, optical coherence tomography (OCT), two-photon microscopy, etc., both in vivo and ex vivo. This design is based on, but not limited to, a home-made prototype of liquid-filled membrane lens with a clear aperture of 8mm and the thickness of 2.55mm ~3.18mm. It is beneficial to have an adaptive objective lens which allows an extended depth scanning range larger than the focal length zoom range, since this will keep the magnification of the whole system, numerical aperture (NA), field of view (FOV), and resolution more consistent. To achieve this goal, a systematic theory is presented, for the first time to our acknowledgment, by inserting the varifocal lens in between a front and a back solid lens group. The designed objective has a compact size (10mm-diameter and 15mm-length), ultrabroad working bandwidth (760nm - 920nm), a large depth scanning range (7.36mm in air) — 1.533 times of focal length zoom range (4.8mm in air), and a FOV around 1mm × 1mm. Diffraction-limited performance can be achieved within this ultrabroad bandwidth through all the scanning depth (the resolution is 2.22 μm - 2.81 μm, calculated at the wavelength of 800nm with the NA of 0.214 - 0.171). The chromatic focal shift value is within the depth of focus (field). The chromatic difference in distortion is nearly zero and the maximum distortion is less than 0.05%. PMID:26417508

  9. Infrared Imaging for Inquiry-Based Learning

    ERIC Educational Resources Information Center

    Xie, Charles; Hazzard, Edmund

    2011-01-01

    Based on detecting long-wavelength infrared (IR) radiation emitted by the subject, IR imaging shows temperature distribution instantaneously and heat flow dynamically. As a picture is worth a thousand words, an IR camera has great potential in teaching heat transfer, which is otherwise invisible. The idea of using IR imaging in teaching was first…

  10. Infrared-based object tracking

    NASA Astrophysics Data System (ADS)

    Gervais, Jon; Youngblood, Austin; Delashmit, Walter H.

    2009-05-01

    Often it is necessary to track moving objects on horizontal paths. Human error and the associated cost and dangers of using humans lead to a requirement to automate this task. The system presented here was designed, built and tested. The system uses an IR beacon and a microcontroller receiver/controller module. The design consists of a field programmable gate array (FPGA) based IR transmitter and a microcontroller based IR receiver/controller. The design consisted of two main parts, the transmitter (beacon) and the receiver/controller module. The receiver was implemented with a FPGA so that the characteristics of the beacon signal could be adjusted more quickly and with greater precision. The controller module was integrated with the receivers and detailed system integration tests were performed. Measurements were collected, recorded and analyzed.

  11. 3D reconstruction of rotational video microscope based on patches

    NASA Astrophysics Data System (ADS)

    Ma, Shijie; Qu, Yufu

    2015-11-01

    Due to the small field of view and shallow depth of field, the microscope could only capture 2D images of the object. In order to observe the three-dimensional structure of the micro object, a microscopy images reconstruction algorithm based on an improved patch-based multi-view stereo (PMVS) algorithm is proposed. The new algorithm improves PMVS from two aspects: first, increasing the propagation directions, second, on the basis of the expansion, different expansion radius and times are set by the angle between the normal vector of the seed patch and the direction vector of the line passing through the seed patch center and the camera center. Compared with PMVS, the number of 3D points made by the new algorithm is three times as much as PMVS. And the holes in the vertical side are also eliminated.

  12. All-optical optoacoustic microscope based on wideband pulse interferometry.

    PubMed

    Wissmeyer, Georg; Soliman, Dominik; Shnaiderman, Rami; Rosenthal, Amir; Ntziachristos, Vasilis

    2016-05-01

    Optical and optoacoustic (photoacoustic) microscopy have been recently joined in hybrid implementations that resolve extended tissue contrast compared to each modality alone. Nevertheless, the application of the hybrid technique is limited by the requirement to combine an optical objective with ultrasound detection collecting signal from the same micro-volume. We present an all-optical optoacoustic microscope based on a pi-phase-shifted fiber Bragg grating (π-FBG) with coherence-restored pulsed interferometry (CRPI) used as the interrogation method. The sensor offers an ultra-small footprint and achieved higher sensitivity over piezoelectric transducers of similar size. We characterize the spectral bandwidth of the ultrasound detector and interrogate the imaging performance on phantoms and tissues. We show the first optoacoustic images of biological specimen recorded with π-FBG sensors. We discuss the potential uses of π-FBG sensors based on CRPI. PMID:27128047

  13. [Multiple transmission electron microscopic image stitching based on sift features].

    PubMed

    Li, Mu; Lu, Yanmeng; Han, Shuaihu; Wu, Zhuobin; Chen, Jiajing; Liu, Zhexing; Cao, Lei

    2015-08-01

    We proposed a new stitching method based on sift features to obtain an enlarged view of transmission electron microscopic (TEM) images with a high resolution. The sift features were extracted from the images, which were then combined with fitted polynomial correction field to correct the images, followed by image alignment based on the sift features. The image seams at the junction were finally removed by Poisson image editing to achieve seamless stitching, which was validated on 60 local glomerular TEM images with an image alignment error of 62.5 to 187.5 nm. Compared with 3 other stitching methods, the proposed method could effectively reduce image deformation and avoid artifacts to facilitate renal biopsy pathological diagnosis. PMID:26403733

  14. Analysis of microscopic infrared spectra of individual dried and live human cells

    NASA Astrophysics Data System (ADS)

    Romeo, Melissa; Matthaus, Christian; Miljkovic, Milos; Boydston-White, Susie; Diem, Max

    2004-07-01

    The ability of infrared (IR) spectroscopy to distinguish and map cancerous and non-cancerous tissue has opened the question of the origin of spectral differences between normal and cancerous cells. In this contribution, we report IR spectral maps of individual dried cancer cells, some of them in the process of cell division (mitosis), IR spectra of cells suspended in growth medium, and preliminary results of a statistical analysis of thousands of individual dried cancer cells.

  15. Highly charged ion based time of flight emission microscope

    DOEpatents

    Barnes, Alan V.; Schenkel, Thomas; Hamza, Alex V.; Schneider, Dieter H.; Doyle, Barney

    2001-01-01

    A highly charged ion based time-of-flight emission microscope has been designed, which improves the surface sensitivity of static SIMS measurements because of the higher ionization probability of highly charged ions. Slow, highly charged ions are produced in an electron beam ion trap and are directed to the sample surface. The sputtered secondary ions and electrons pass through a specially designed objective lens to a microchannel plate detector. This new instrument permits high surface sensitivity (10.sup.10 atoms/cm.sup.2), high spatial resolution (100 nm), and chemical structural information due to the high molecular ion yields. The high secondary ion yield permits coincidence counting, which can be used to enhance determination of chemical and topological structure and to correlate specific molecular species.

  16. Near-infrared detection of potential evidence for microscopic organisms on Europa

    NASA Technical Reports Server (NTRS)

    Dalton, J. Brad; Mogul, Rakesh; Kagawa, Hiromi K.; Chan, Suzanne L.; Jamieson, Corey S.

    2003-01-01

    The possibility of an ocean within the icy shell of Jupiter's moon Europa has established that world as a primary candidate in the search for extraterrestrial life within our Solar System. This paper evaluates the potential to detect evidence for microbial life by comparing laboratory studies of terrestrial microorganisms with measurements from the Galileo Near Infrared Imaging Spectrometer (NIMS). If the interior of Europa at one time harbored life, some evidence may remain in the surface materials. Examination of laboratory spectra of terrestrial extremophiles measured at cryogenic temperatures reveals distorted, asymmetric nearinfrared absorption features due to water of hydration. The band centers, widths, and shapes of these features closely match those observed in the Europa spectra. These features are strongest in reddish-brown, disrupted terrains such as linea and chaos regions. Narrow spectral features due to amide bonds in the microbe proteins provide a means of constraining the abundances of such materials using the NIMS data. The NIMS data of disrupted terrains exhibit distorted, asymmetric near-infrared absorption features consistent with the presence of water ice, sulfuric acid octahydrate, hydrated salts, and possibly as much as 0.2 mg cm(-3) of carbonaceous material that could be of biological origin. However, inherent noise in the observations and limitations of spectral sampling must be taken into account when discussing these findings.

  17. Near-infrared detection of potential evidence for microscopic organisms on Europa.

    PubMed

    Dalton, J Brad; Mogul, Rakesh; Kagawa, Hiromi K; Chan, Suzanne L; Jamieson, Corey S

    2003-01-01

    The possibility of an ocean within the icy shell of Jupiter's moon Europa has established that world as a primary candidate in the search for extraterrestrial life within our Solar System. This paper evaluates the potential to detect evidence for microbial life by comparing laboratory studies of terrestrial microorganisms with measurements from the Galileo Near Infrared Imaging Spectrometer (NIMS). If the interior of Europa at one time harbored life, some evidence may remain in the surface materials. Examination of laboratory spectra of terrestrial extremophiles measured at cryogenic temperatures reveals distorted, asymmetric nearinfrared absorption features due to water of hydration. The band centers, widths, and shapes of these features closely match those observed in the Europa spectra. These features are strongest in reddish-brown, disrupted terrains such as linea and chaos regions. Narrow spectral features due to amide bonds in the microbe proteins provide a means of constraining the abundances of such materials using the NIMS data. The NIMS data of disrupted terrains exhibit distorted, asymmetric near-infrared absorption features consistent with the presence of water ice, sulfuric acid octahydrate, hydrated salts, and possibly as much as 0.2 mg cm(-3) of carbonaceous material that could be of biological origin. However, inherent noise in the observations and limitations of spectral sampling must be taken into account when discussing these findings. PMID:14678661

  18. Post-mortem interval estimation of human skeletal remains by micro-computed tomography, mid-infrared microscopic imaging and energy dispersive X-ray mapping

    PubMed Central

    Hatzer-Grubwieser, P.; Bauer, C.; Parson, W.; Unterberger, S. H.; Kuhn, V.; Pemberger, N.; Pallua, Anton K.; Recheis, W.; Lackner, R.; Stalder, R.; Pallua, J. D.

    2015-01-01

    In this study different state-of-the-art visualization methods such as micro-computed tomography (micro-CT), mid-infrared (MIR) microscopic imaging and energy dispersive X-ray (EDS) mapping were evaluated to study human skeletal remains for the determination of the post-mortem interval (PMI). PMI specific features were identified and visualized by overlaying molecular imaging data and morphological tissue structures generated by radiological techniques and microscopic images gained from confocal microscopy (Infinite Focus (IFM)). In this way, a more distinct picture concerning processes during the PMI as well as a more realistic approximation of the PMI were achieved. It could be demonstrated that the gained result in combination with multivariate data analysis can be used to predict the Ca/C ratio and bone volume (BV) over total volume (TV) for PMI estimation. Statistical limitation of this study is the small sample size, and future work will be based on more specimens to develop a screening tool for PMI based on the outcome of this multidimensional approach. PMID:25878731

  19. Pyroelectric infrared linear arrays based on PIMNT

    NASA Astrophysics Data System (ADS)

    Ma, Xueliang; Shao, Xiumei; Yu, Yuehua; Luo, Haosu; Liu, Linhua; Xia, Wang; Li, Yanjin

    2012-10-01

    Pyroelectric infrared linear arrays can work at ambient temperature without cryogenic system and have the merits of comparatively homogenous spectral response in wide spectrum range, compact structure, long-time stability and low cost for many applications. xPb(In1/2Nb1/2)O3-yPb(Mg1/3Nb2/3)O3-(1-x-y)PbTiO3 (PIMNT) single crystal is a kind of novel pyroelectric material, which possesses superior pyroelectric performances and is appraised as a candidate for high performance pyroelectric infrared linear arrays. This paper describes the layout and essential properties of the pyroelectric infrared linear arrays based on PIMNT with 128 responsive elements. The transmittance measurement of PIMNT indicates that an absorption layer is needed when the PIMNT based linear arrays work at room temperature in 0.8 - 12.0 μm wave range due to the low absorption ratio especially in 0.8 - 10.0 μm wave band. The arrays employ a hybrid structure consisting of the PIMNT pyroelectric chip and CMOS read-out circuit. They are electrically bonded by ultrasonic bonding process. Also some details of the process technologies of the PIMNT pyroelectric chip are depicted in this paper.

  20. Research on infrared imaging illumination model based on materials

    NASA Astrophysics Data System (ADS)

    Hu, Hai-he; Feng, Chao-yin; Guo, Chang-geng; Zheng, Hai-jing; Han, Qiang; Hu, Hai-yan

    2013-09-01

    In order to effectively simulate infrared features of the scene and infrared high light phenomenon, Based on the visual light illumination model, according to the optical property of all material types in the scene, the infrared imaging illumination models are proposed to fulfill different materials: to the smooth material with specular characteristic, adopting the infrared imaging illumination model based on Blinn-Phone reflection model and introducing the self emission; to the ordinary material which is similar to black body without highlight feature, ignoring the computation of its high light reflection feature, calculating simply the material's self emission and its reflection to the surrounding as its infrared imaging illumination model, the radiation energy under zero range of visibility can be obtained according to the above two models. The OpenGl rendering technology is used to construct infrared scene simulation system which can also simulate infrared electro-optical imaging system, then gets the synthetic infrared images from any angle of view of the 3D scenes. To validate the infrared imaging illumination model, two typical 3D scenes are made, and their infrared images are calculated to compare and contrast with the real collected infrared images obtained by a long wave infrared band imaging camera. There are two major points in the paper according to the experiment results: firstly, the infrared imaging illumination models are capable of producing infrared images which are very similar to those received by thermal infrared camera; secondly, the infrared imaging illumination models can simulate the infrared specular feature of relative materials and common infrared features of general materials, which shows the validation of the infrared imaging illumination models. Quantitative analysis shows that the simulation images are similar to the collected images in the aspects of main features, but their histogram distribution does not match very well, the

  1. Optical microscope combined with the nanopipette-based quartz tuning fork-atomic force microscope for nanolithography

    NASA Astrophysics Data System (ADS)

    An, Sangmin; Stambaugh, Corey; Kwon, Soyoung; Lee, Kunyoung; Kim, Bongsu; Kim, Qwhan; Jhe, Wonho

    2013-09-01

    We demonstrated the optical microscope (OM) combined with nanopipette-based quartz tuning fork - atomic force microscope (QTF-AFM) for nanolithography. The nanoparticle (Au, 5 nm), nanowire, PDMS solutions are ejected onto the substrate through the nano/microaperture of the pulled pipette, and the nano/microscale objects were in-situ formed on the surface with the proposed patterning system, while the position is defined by monitoring the phenomena on the substrate with a home-made OM. After forming of capillary condensation between apex of the pipette tip and the surface, the electric field is applied to extract out the inside liquid to the substrate and the nano/microscale objects are fabricated. The nanoscale patterning size can be controlled by the aperture diameters of the pulled pipette.

  2. [Myanmar jadeitite low-temperature metamorphic water-rock reaction: eveidence from microscopic fourier transform infrared spectroscopy].

    PubMed

    Yan, Ruo-Gu; Qiu, Zhi-Li; Feng, Ming; Jin, Chun-Mei; Li, Liu-Fen; Shi, Gui-Yong; Wang, Ping

    2014-09-01

    Weathering & transporting and depositing processes may improve the quality of some natural low-quality jadeite through reaction with surrounding water fluids. But the mechanism of such water-rock reaction has not been known clearly to date. Applying microscopic Fourier transform infrared spectroscopy (Micro-FTIR), this paper carried out comparatively in-situ research of jadeites' mineral composition before and after water-rock reaction. The results show that water-rock reaction cannot impact jadeites in their major and minor element composition, but greatly change their water content. Jadeites became richer, with even several times increase, in water content, after experiencing water-rock reaction, and hence show a shift of absorption peak at 3 550 cm(-1) to higher frequency. The mineral crystals of these jadeites showed reglar variation in water content from core to edge, and these jadeites have more water in marginal area than in center area, being opposite to the change in water content in jadeite during high temperature and pressure metamorphic process, hence implying that there are different mechanism and shift direction for H+/OH of jadeite between high pressure metamorphic process and low temperature water-rock reaction. We think that this finding may contribute to understanding the behavior of water in jadeite during metamorphic process and the mechanism of jadeite quality improvement. PMID:25532333

  3. Apparatus for measuring Seebeck coefficient and electrical resistivity of small dimension samples using infrared microscope as temperature sensor

    NASA Astrophysics Data System (ADS)

    Jaafar, W. M. N. Wan; Snyder, J. E.; Min, Gao

    2013-05-01

    An apparatus for measuring the Seebeck coefficient (α) and electrical resistivity (ρ) was designed to operate under an infrared microscope. A unique feature of this apparatus is its capability of measuring α and ρ of small-dimension (sub-millimeter) samples without the need for microfabrication. An essential part of this apparatus is a four-probe assembly that has one heated probe, which combines the hot probe technique with the Van der Pauw method for "simultaneous" measurements of the Seebeck coefficient and electrical resistivity. The repeatability of the apparatus was investigated over a temperature range of 40 °C-100 °C using a nickel plate as a standard reference. The results show that the apparatus has an uncertainty of ±4.9% for Seebeck coefficient and ±5.0% for electrical resistivity. The standard deviation of the apparatus against a nickel reference sample is -2.43 μVK-1 (-12.5%) for the Seebeck coefficient and -0.4 μΩ cm (-4.6%) for the electrical resistivity, respectively.

  4. Advanced MEMS-based infrared imager

    NASA Astrophysics Data System (ADS)

    Chen, Ming

    2003-04-01

    Infrared radiation imager is of important for a wide range of applications. IR infrared imagers have not been widely available due to cost and complexity issues. A major cost of IR imager is associated with the requirements of cooling and pixel-level integration with electronic amplifier and read-out circuitry that are often incompatible with the detector materials. Recent research activities have lead to a new class of IR imager based on thermally isolated MEMS (micro-electromechanical systems) arrays whose bending can be directly detected by optical means. This approach eliminates the need for cooling and complex electronic multiplexers, holding the potential to drastically reduce IR imager cost. However, MEMS based IR imaging devices demonstrated to date are less sensitive than the commercially available ones. We have established a comprehensive finite element model (FEM) using Ansys tool. An accurate computer model for the proposed MEME IR detector is critical for the device development and fabrication. The model greatly enhanced our capability to cost effectively optimize the design from concept to fabrication layout. Our model predicts the deformation of this pixel structure under a surface stress for both thermal and photo-induced effects under various conditions. This simulation model provided a design base for new generation of optical MEMS IR sensors that has higher sensitivity and the potential of incorporating passive thermal amplification. Our simple MEMS design incorporates optical read-out, which eliminates the drawback of electronic means that inevitably introduce additional signal loss due to thermal contact made to the detector element. When packaged under vacuum environment, significant sensitivity improvement is anticipated. The deflection of a cantilever as a function of a rise in its temperature is determined by the classical thermomechanical governing equation for a bimaterial cantilever beam. Our finite element model is established using

  5. [Bone Cell Biology Assessed by Microscopic Approach. Assessment of bone quality using Raman and infrared spectroscopy].

    PubMed

    Suda, Hiromi Kimura

    2015-10-01

    Bone quality, which was defined as "the sum total of characteristics of the bone that influence the bone's resistance to fracture" at the National Institute of Health (NIH) conference in 2001, contributes to bone strength in combination with bone mass. Bone mass is often measured as bone mineral density (BMD) and, consequently, can be quantified easily. On the other hand, bone quality is composed of several factors such as bone structure, bone matrix, calcification degree, microdamage, and bone turnover, and it is not easy to obtain data for the various factors. Therefore, it is difficult to quantify bone quality. We are eager to develop new measurement methods for bone quality that make it possible to determine several factors associated with bone quality at the same time. Analytic methods based on Raman and FTIR spectroscopy have attracted a good deal of attention as they can provide a good deal of chemical information about hydroxyapatite and collagen, which are the main components of bone. A lot of studies on bone quality using Raman and FTIR imaging have been reported following the development of the two imaging systems. Thus, both Raman and FTIR imaging appear to be promising new bone morphometric techniques. PMID:26412727

  6. Near-infrared microscopic methods for the detection and quantification of processed by-products of animal origin

    NASA Astrophysics Data System (ADS)

    Abbas, O.; Fernández Pierna, J. A.; Dardenne, P.; Baeten, V.

    2010-04-01

    Since the BSE crisis, researches concern mainly the detection, identification, and quantification of meat and bone meal with an important focus on the development of new analytical methods. Microscopic based spectroscopy methods (NIR microscopy - NIRM or/and NIR hyperspectral imaging) have been proposed as complementary methods to the official method; the optical microscopy. NIR spectroscopy offers the advantage of being rapid, accurate and independent of human analyst skills. The combination of an NIR detector and a microscope or a camera allows the collection of high quality spectra for small feed particles having a size larger than 50 μm. Several studies undertaken have demonstrated the clear potential of NIR microscopic methods for the detection of animal particles in both raw and sediment fractions. Samples are sieved and only the gross fraction (superior than 250 μm) is investigated. Proposed methodologies have been developed to assure, with an acceptable level of confidence (95%), the detection of at least one animal particle when a feed sample is adulterated at a level of 0.1%. NIRM and NIR hyperspectral imaging are running under accreditation ISO 17025 since 2005 at CRA-W. A quantitative NIRM approach has been developed in order to fulfill the new requirements of the European commission policies. The capacities of NIRM method have been improved; only the raw fraction is analyzed, both the gross and the fine fractions of the samples are considered, and the acquisition parameters are optimized (the aperture, the gap, and the composition of the animal feed). A mapping method for a faster collection of spectra is also developed. The aim of this work is to show the new advances in the analytical methods developed in the frame of the feed ban applied in Europe.

  7. Satellite Characterization of Biomass Burning: Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope Study of Combustion Experiments

    NASA Astrophysics Data System (ADS)

    Padilla, D.; Steiner, J. C.

    2005-12-01

    Fourier Transform Infrared (FTIR) examination of the combustion products of selected forest materials using a meeker burner flame at temperatures up to 500 degrees Celsius produces a cluster of broad distinct peaks throughout the 400 to 4000 cm-1 wavenumber interval. Distinct bands bracketed by wavenumbers 400-700, 1500-1700, 2200-2400 and 3300-3600 cm-1 show variable intensity with an average difference between the least absorbing and most strongly absorbing species of approximately fifty percent. Given that spectral band differences of ten percent are within the range of modern satellite spectrometers, these band differences are of potential value for discriminating between fires that are impacting a range of vegetation types. Corresponding scanning electron microscope and energy dispersive micro-chemical (SEM/ED) analysis establishes that the evolved soot particles exhibit a characteristic rounded morphology, are carbon rich and host a wide range of adsorbed elements, including calcium, aluminum, potassium, silicon, sulfur and trace nitrogen. Combustion experiments involving leaves and branches as a subset of the biomass experiments at 200-500 degrees Celsius yield a similar broad background, but with peak shifts for maxima residing at less than 1700 cm-1. Additional peaks appear in the ranges 1438-1444, 875 and 713 cm-1. These peak are of potential use for discriminating between hot and smoldering fires, and between soot and smoke yields from green woods and whole-wood or lumber. The spectral shifts noted for low temperature smoldering conditions are in the vicinity of those cited for green vegetation and may not be resolved by present satellite platforms. Nevertheless, the experimental peak data set is of potential use for discriminating between a conflagration or accentuated fire and one characterized by smoldering at low temperature. SEM/ED analysis of the combusted leaf, branch, bark and various crown assemblages yields comparable morphological and

  8. Infrared Imaging for Inquiry-Based Learning

    NASA Astrophysics Data System (ADS)

    Xie, Charles; Hazzard, Edmund

    2011-09-01

    Based on detecting long-wavelength infrared (IR) radiation emitted by the subject, IR imaging shows temperature distribution instantaneously and heat flow dynamically. As a picture is worth a thousand words, an IR camera has great potential in teaching heat transfer, which is otherwise invisible. The idea of using IR imaging in teaching was first discussed by Vollmer et al. in 2001.1-3 IR cameras were then too expensive for most schools. Thanks to the growing need of home energy inspection using IR thermography, the price of IR cameras has plummeted and they have become easy to use. As of 2011, the price of an entry-level handheld IR camera such as the FLIR I3 has fallen below 900 for educators. A slightly better version, FLIR I5, was used to take the IR images in this paper. As easy to use as a digital camera, the I5 camera automatically generates IR images of satisfactory quality with a temperature sensitivity of 0.1°C. The purpose of this paper is to demonstrate how these affordable IR cameras can be used as a visualization, inquiry, and discovery tool. As the prices of IR cameras continue to drop, it is time to give teachers an update about the educational power of this fascinating tool, especially in supporting inquiry-based learning.

  9. Microscopic oxygen imaging based on fluorescein bleaching efficiency measurements.

    PubMed

    Beutler, Martin; Heisterkamp, Ines M; Piltz, Bastian; Stief, Peter; De Beer, Dirk

    2014-05-01

    Photobleaching of the fluorophore fluorescein in an aqueous solution is dependent on the oxygen concentration. Therefore, the time-dependent bleaching behavior can be used to measure of dissolved oxygen concentrations. The method can be combined with epi-fluorescence microscopy. The molecular states of the fluorophore can be expressed by a three-state energy model. This leads to a set of differential equations which describe the photobleaching behavior of fluorescein. The numerical solution of these equations shows that in a conventional wide-field fluorescence microscope, the fluorescence of fluorescein will fade out faster at low than at high oxygen concentration. Further simulation showed that a simple ratio function of different time-points during a fluorescence decay recorded during photobleaching could be used to describe oxygen concentrations in an aqueous solution. By careful choice of dye concentration and excitation light intensity the sensitivity in the oxygen concentration range of interest can be optimized. In the simulations, the estimation of oxygen concentration by the ratio function was very little affected by the pH value in the range of pH 6.5-8.5. Filming the fluorescence decay by a charge-coupled-device (ccd) camera mounted on a fluorescence microscope allowed a pixelwise estimation of the ratio function in a microscopic image. Use of a microsensor and oxygen-consuming bacteria in a sample chamber enabled the calibration of the system for quantification of absolute oxygen concentrations. The method was demonstrated on nitrifying biofilms growing on snail and mussel shells, showing clear effects of metabolic activity on oxygen concentrations. PMID:24610786

  10. A stacking-fault based microscopic model for platelets in diamond

    NASA Astrophysics Data System (ADS)

    Antonelli, Alex; Nunes, Ricardo

    2005-03-01

    We propose a new microscopic model for the 001 planar defects in diamond commonly called platelets. This model is based on the formation of a metastable stacking fault, which can occur because of the ability of carbon to stabilize in different bonding configurations. In our model the core of the planar defect is basically a double layer of three-fold coordinated sp^2 carbon atoms embedded in the common sp^3 diamond structure. The properties of the model were determined using ab initio total energy calculations. All significant experimental signatures attributed to the platelets, namely, the lattice displacement along the [001] direction, the asymmetry between the [110] and the [11 0] directions, the infrared absorption peak B^' , and broad luminescence lines that indicate the introduction of levels in the band gap, are naturally accounted for in our model. The model is also very appealing from the point of view of kinetics, since naturally occurring shearing processes will lead to the formation of the metastable fault.Authors acknowledge financial support from the Brazilian agencies FAPESP, CNPq, FAEP-UNICAMP, FAPEMIG, and Instituto do Milênio em Nanociências-MCT

  11. INTERFEROGRAM-BASED INFRARED SEARCH SYSTEM

    EPA Science Inventory

    A computerized search routine for the identification of infrared spectra using interferometric data exclusively is described. Two forms of instrument-dependent information present in raw interferometric data are removed prior to the search process. Interferometric phase error is ...

  12. Modulation method for infrared communication based on a MEMS Planck infrared source

    NASA Astrophysics Data System (ADS)

    Wei, Hongjing; Ma, Li; Sun, Guofeng; Jia, Jun

    2012-12-01

    Infrared communication in the near ground free space has both military and civilian potential. To meet the requirements of infrared communication based on a micro-electro-mechanical system Planck infrared source/radiator, we propose a modulation method with large code information content, strong confidentiality, and a high recognition rate. With the characteristics of mid-infrared light, a long-range and anti-EMI wireless communication system is available. The information code is loaded on the carrier signal generated by the infrared source with specific frequency. Taking a 3×3 array system for an instance in our work, the design principle and implementation procedure of encoding and modulation is discussed. The total information content of the optical dynamic code is 1.5 kbytes. The communication system could transmit data in the bound rate of 900 bit/s with a photoelectric code recognition rate of 96.4% and an effective information content of 190 bytes.

  13. [Polar coordinates representation based leukocyte segmentation of microscopic cell images].

    PubMed

    Gu, Guanghua; Cui, Dong; Hao, Lianwang

    2010-12-01

    We propose an algorithm for segmentation of the overlapped leukocyte in the microscopic cell image. The histogram of the saturation channel in the cell image is smoothed to obtain the meaningful global valley point by the fingerprint smoothing method, and then the nucleus can be segmented. A circular region, containing the entire regions of the leukocyte, is marked off according to the equivalent sectional radius of the nucleus. Then, the edge of the overlapped leukocyte is represented by polar coordinates. The overlapped region by the change of the polar angle of the edge pixels is determined, and the closed edge of the leukocyte integrating the gradient information of the overlapped region is reconstructed. Finally, the leukocyte is exactly extracted. The experimental results show that our method has good performance in terms of recall ratio, precision ratio and pixel error ratio. PMID:21374971

  14. SOFI-based 3D superresolution sectioning with a widefield microscope

    PubMed Central

    Dertinger, Thomas; Xu, Jianmin; Naini, Omeed Foroutan; Vogel, Robert; Weiss, Shimon

    2013-01-01

    Background Fluorescence-based biological imaging has been revolutionized by the recent introduction of superresolution microscopy methods. 3D superresolution microscopy, however, remains a challenge as its implementation by existing superresolution methods is non-trivial. Methods Here we demonstrate a facile and straightforward 3D superresolution imaging and sectioning of the cytoskeletal network of a fixed cell using superresolution optical fluctuation imaging (SOFI) performed on a conventional lamp-based widefield microscope. Results and Conclusion SOFI’s inherent sectioning capability effectively transforms a conventional widefield microscope into a superresolution ‘confocal widefield’ microscope. PMID:24163789

  15. Shape quantification of single red blood cells based on their scattering patterns from microscopic images

    NASA Astrophysics Data System (ADS)

    Schneider, Gert; Artmann, Gerhard

    1995-02-01

    The differentiation between discocytic and stomatocytic red blood cell (RBC) shape using conventional microscopic imaging and image analysis tools is still on a very poor level. A procedure to differentiate the degree of stomatocytic shape changes was developed. We obtained multiple microscopic images of the same RBCs settled on a human albumin coated cover slip. The images were acquired when the microscope objective was subsequently focused through the cell layer. At equidistant horizontal planes (z-axis) below, within, and above the microscopic focal plane the light intensity distribution was considered. Using a model based on light refraction, we calculated the intensity distribution of the planes which are out of focus. Using this tool we are able to differentiate RBC shapes precisely. On the other hand, using this model from and the light intensity distributions of different focal planes, we are able to reconstruct the shape of one single RBC located in the optical axis of the microscope.

  16. Towards a Microscopic Reaction Description Based on Energy Density Functionals

    SciTech Connect

    Nobre, G A; DIetrich, F S; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J; Engel, J

    2011-09-26

    A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for {sup 40,48}Ca, {sup 58}Ni, {sup 90}Zr and {sup 144}Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agree very well with experimental data and predictions of a state-of-the-art fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. The effect of resonances from higher-order channels was assessed. Elastic angular distributions were also calculated within the same method, achieving good agreement with experimental data. For the first time observed absorptions are completely accounted for by explicit channel coupling, for incident energies between 10 and 70 MeV, with consistent angular distribution results.

  17. Microscopic transport model animation visualisation on KML base

    NASA Astrophysics Data System (ADS)

    Yatskiv, I.; Savrasovs, M.

    2012-10-01

    By reading classical literature devoted to the simulation theory it could be found that one of the greatest possibilities of simulation is the ability to present processes inside the system by animation. This gives to the simulation model additional value during presentation of simulation results for the public and authorities who are not familiar enough with simulation. That is why most of universal and specialised simulation tools have the ability to construct 2D and 3D representation of the model. Usually the development of such representation could take much time and there must be put a lot forces into creating an adequate 3D representation of the model. For long years such well-known microscopic traffic flow simulation software tools as VISSIM, AIMSUN and PARAMICS have had a possibility to produce 2D and 3D animation. But creation of realistic 3D model of the place where traffic flows are simulated, even in these professional software tools it is a hard and time consuming action. The goal of this paper is to describe the concepts of use the existing on-line geographical information systems for visualisation of animation produced by simulation software. For demonstration purposes the following technologies and tools have been used: PTV VISION VISSIM, KML and Google Earth.

  18. Martian Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The microscopic imager (circular device in center) is in clear view above the surface at Meridiani Planum, Mars, in this approximate true-color image taken by the panoramic camera on the Mars Exploration Rover Opportunity. The image was taken on the 9th sol of the rover's journey. The microscopic imager is located on the rover's instrument deployment device, or arm. The arrow is pointing to the lens of the instrument. Note the dust cover, which flips out to the left of the lens, is open. This approximated color image was created using the camera's violet and infrared filters as blue and red.

  19. Infrared

    NASA Astrophysics Data System (ADS)

    Vollmer, M.

    2013-11-01

    'Infrared' is a very wide field in physics and the natural sciences which has evolved enormously in recent decades. It all started in 1800 with Friedrich Wilhelm Herschel's discovery of infrared (IR) radiation within the spectrum of the Sun. Thereafter a few important milestones towards widespread use of IR were the quantitative description of the laws of blackbody radiation by Max Planck in 1900; the application of quantum mechanics to understand the rotational-vibrational spectra of molecules starting in the first half of the 20th century; and the revolution in source and detector technologies due to micro-technological breakthroughs towards the end of the 20th century. This has led to much high-quality and sophisticated equipment in terms of detectors, sources and instruments in the IR spectral range, with a multitude of different applications in science and technology. This special issue tries to focus on a few aspects of the astonishing variety of different disciplines, techniques and applications concerning the general topic of infrared radiation. Part of the content is based upon an interdisciplinary international conference on the topic held in 2012 in Bad Honnef, Germany. It is hoped that the information provided here may be useful for teaching the general topic of electromagnetic radiation in the IR spectral range in advanced university courses for postgraduate students. In the most general terms, the infrared spectral range is defined to extend from wavelengths of 780 nm (upper range of the VIS spectral range) up to wavelengths of 1 mm (lower end of the microwave range). Various definitions of near, middle and far infrared or thermal infrared, and lately terahertz frequencies, are used, which all fall in this range. These special definitions often depend on the scientific field of research. Unfortunately, many of these fields seem to have developed independently from neighbouring disciplines, although they deal with very similar topics in respect of the

  20. Space-based infrared surveys of small bodies

    NASA Astrophysics Data System (ADS)

    Mommert, M.

    2014-07-01

    Most small bodies in the Solar System are too small and too distant to be spatially resolved, precluding a direct diameter derivation. Furthermore, measurements of the optical brightness alone only allow a rough estimate of the diameter, since the surface albedo is usually unknown and can have values between about 3 % and 60 % or more. The degeneracy can be resolved by considering the thermal emission of these objects, which is less prone to albedo effects and mainly a function of the diameter. Hence, the combination of optical and thermal-infrared observational data provides a means to independently derive an object's diameter and albedo. This technique is used in asteroid thermal models or more sophisticated thermophysical models (see, e.g., [1]). Infrared observations require cryogenic detectors and/or telescopes, depending on the actual wavelength range observed. Observations from the ground are additionally compromised by the variable transparency of Earth's atmosphere in major portions of the infrared wavelength ranges. Hence, space-based infrared telescopes, providing stable conditions and significantly better sensitivities than ground-based telescopes, are now used routinely to exploit this wavelength range. Two observation strategies are used with space-based infrared observatories: Space-based Infrared All-Sky Surveys. Asteroid surveys in the thermal infrared are less prone to albedo-related discovery bias compared to surveys with optical telescopes, providing a more complete picture of small body populations. The first space-based infrared survey of Solar System small bodies was performed with the Infrared Astronomical Satellite (IRAS) for 10 months in 1983. In the course of the 'IRAS Minor Planet Survey' [2], 2228 asteroids (3 new discoveries) and more than 25 comets (6 new discoveries) were observed. More recent space-based infrared all-sky asteroid surveys were performed by Akari (launched 2006) and the Wide-field Infrared Survey Explorer (WISE

  1. Microscopic colitis.

    PubMed

    Pardi, Darrell S

    2014-02-01

    Microscopic colitis is a frequent cause of chronic watery diarrhea, especially in older persons. Common associated symptoms include abdominal pain, arthralgias, and weight loss. The incidence of microscopic colitis had been increasing, although more recent studies have shown a stabilization of incidence rates. The diagnosis is based on characteristic histologic findings in a patient with diarrhea. Microscopic colitis can occur at any age, including in children, but it is primarily seen in the elderly. Several treatment options exist to treat the symptoms of microscopic colitis, although only budesonide has been well studied in randomized clinical trials. PMID:24267602

  2. Inquiry-based Science Activities Using The Infrared Zoo and Infrared Yellowstone Resources at Cool Cosmos

    NASA Astrophysics Data System (ADS)

    Daou, D.; Gauthier, A.

    2003-12-01

    Inquiry-based activities that utilize the Cool Cosmos image galleries have been designed and developed by K12 teachers enrolled in The Invisible Universe Online for Teachers course. The exploration activities integrate the Our Infrared World Gallery (http://coolcosmos.ipac.caltech.edu/image_galleries/our_ir_world_gallery.html) with either the Infrared Zoo gallery (http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/index.html) or the Infrared Yellowstone image http://coolcosmos.ipac.caltech.edu/image_galleries/ir_yellowstone/index.html) and video (http://coolcosmos.ipac.caltech.edu/videos/ir_yellowstone/index.html) galleries. Complete instructor guides have been developed for the activities and will be presented by the authors in poster and CD form. Although the activities are written for middle and highschool learners, they can easily be adapted for college audiences. The Our Infrared World Gallery exploration helps learners think critically about visible light and infrared light as they compare sets of images (IR and visible light) of known objects. For example: by taking a regular photograph of a running faucet, can you tell if it is running hot or cold water? What new information does the IR image give you? The Infrared Zoo activities encourage learners to investigate the differences between warm and cold blooded animals by comparing sets of IR and visible images. In one activity, learners take on the role of a pit viper seeking prey in various desert and woodland settings. The main activities are extended into the real world by discussing and researching industrial, medical, and societal applications of infrared technologies. The Infrared Yellowstone lessons give learners a unique perspective on Yellowstone National Park and it's spectacular geologic and geothermal features. Infrared video technology is highlighted as learners make detailed observations about the visible and infrared views of the natural phenomena. The "Cool Cosmos" EPO activities are

  3. Model based control of dynamic atomic force microscope

    SciTech Connect

    Lee, Chibum; Salapaka, Srinivasa M.

    2015-04-15

    A model-based robust control approach is proposed that significantly improves imaging bandwidth for the dynamic mode atomic force microscopy. A model for cantilever oscillation amplitude and phase dynamics is derived and used for the control design. In particular, the control design is based on a linearized model and robust H{sub ∞} control theory. This design yields a significant improvement when compared to the conventional proportional-integral designs and verified by experiments.

  4. Model based control of dynamic atomic force microscope.

    PubMed

    Lee, Chibum; Salapaka, Srinivasa M

    2015-04-01

    A model-based robust control approach is proposed that significantly improves imaging bandwidth for the dynamic mode atomic force microscopy. A model for cantilever oscillation amplitude and phase dynamics is derived and used for the control design. In particular, the control design is based on a linearized model and robust H(∞) control theory. This design yields a significant improvement when compared to the conventional proportional-integral designs and verified by experiments. PMID:25933864

  5. Temperature-sensitive junction transformations for mid-wavelength HgCdTe photovoltaic infrared detector arrays by laser beam induced current microscope

    SciTech Connect

    Qiu, Weicheng; Hu, Weida Lin, Tie; Yin, Fei; Zhang, Bo; Chen, Xiaoshuang; Lu, Wei; Cheng, Xiang'ai Wang, Rui

    2014-11-10

    In this paper, we report on the disappearance of the photosensitive area extension effect and the unusual temperature dependence of junction transformation for mid-wavelength, n-on-p HgCdTe photovoltaic infrared detector arrays. The n-type region is formed by B{sup +} ion implantation on Hg-vacancy-doped p-type HgCdTe. Junction transformations under different temperatures are visually captured by a laser beam induced current microscope. A physical model of temperature dependence on junction transformation is proposed and demonstrated by using numerical simulations. It is shown that Hg-interstitial diffusion and temperature activated defects jointly lead to the p-n junction transformation dependence on temperature, and the weaker mixed conduction compared with long-wavelength HgCdTe photodiode contributes to the disappearance of the photosensitive area extension effect in mid-wavelength HgCdTe infrared detector arrays.

  6. A background suppression algorithm for infrared image based on shearlet

    NASA Astrophysics Data System (ADS)

    Zou, Ruibin; Shi, Caicheng; Qin, Xiao

    2015-04-01

    Because of the relative far distance between infrared imaging system and target or the wide field infrared optical, the imaging area of infrared target is only a few pixels, which is isolated or spots to be showed in the field of view. The only available is the intensity information (gray value) for the target detection. Simultaneously, there are many shortcomings of the infrared image, such as large noise, interference and so on, therefore the small target is always buried in the background and noises. The small target is relatively difficult to detect, so generally, it is impossible to make reliable detection to this target in a single frame image. Summarily, the core of the infrared small target detection algorithm is the background and noise suppression based on a single frame image. Aiming at the infrared small target detection and the above problems, a shearlets-based background suppression algorithm for infrared image is proposed. The algorithm demonstrates the performance of advantage based on shearlets, which is especially designed to address anisotropic and directional information at various scales. This transform provides an optimally efficient representation of images, which is greatly reduced the amount of the information and the available information representation. In the paper, introducing the principle of shearlets first, and then proposing the theory of the algorithm and explaining the implementation step. Finally, giving the simulation results. In Matlab simulations with this method for several sets of infrared images, simulation results conformed to the theory on background suppression based on shearlets. The result showed that this method can effectively suppress background, and improve the SCR and achieve a satisfactory effect in the sky background. The method is very effectively for target detection, identification, track in infrared image system for the future.

  7. Novel infrared detector based on a tunneling displacement transducer

    NASA Technical Reports Server (NTRS)

    Kenny, T. W.; Kaiser, W. J.; Waltman, S. B.; Reynolds, J. K.

    1991-01-01

    The paper describes the design, fabrication, and characteristics of a novel infrared detector based on the principle of Golay's (1947) pneumatic infrared detector, which uses the expansion of a gas to detect infrared radiation. The present detector is constructed entirely from micromachined silicon and uses an electron tunneling displacement transducer for the detection of gas expansion. The sensitivity of the new detector is competitive with the best commercial pyroelectric sensors and can be readily improved by an order of magnitude through the use of an optimized transducer.

  8. Reproducing kernel hilbert space based single infrared image super resolution

    NASA Astrophysics Data System (ADS)

    Chen, Liangliang; Deng, Liangjian; Shen, Wei; Xi, Ning; Zhou, Zhanxin; Song, Bo; Yang, Yongliang; Cheng, Yu; Dong, Lixin

    2016-07-01

    The spatial resolution of Infrared (IR) images is limited by lens optical diffraction, sensor array pitch size and pixel dimension. In this work, a robust model is proposed to reconstruct high resolution infrared image via a single low resolution sampling, where the image features are discussed and classified as reflective, cooled emissive and uncooled emissive based on infrared irradiation source. A spline based reproducing kernel hilbert space and approximative heaviside function are deployed to model smooth part and edge component of image respectively. By adjusting the parameters of heaviside function, the proposed model can enhance distinct part of images. The experimental results show that the model is applicable on both reflective and emissive low resolution infrared images to improve thermal contrast. The overall outcome produces a high resolution IR image, which makes IR camera better measurement accuracy and observes more details at long distance.

  9. Design of integration-ready metasurface-based infrared absorbers

    SciTech Connect

    Ogando, Karim Pastoriza, Hernán

    2015-07-28

    We introduce an integration ready design of metamaterial infrared absorber, highly compatible with many kinds of fabrication processes. We present the results of an exhaustive experimental characterization, including an analysis of the effects of single meta-atom geometrical parameters and collective arrangement. We confront the results with the theoretical interpretations proposed in the literature. Based on the results, we develop a set of practical design rules for metamaterial absorbers in the infrared region.

  10. The standardization of super resolution optical microscopic images based on DICOM

    NASA Astrophysics Data System (ADS)

    Xia, Wei; Gao, Xin

    2015-03-01

    Super resolution optical microscopy allows the capture of images with a higher resolution than the diffraction limit. However, due to the lack of a standard format, the processing, visualization, transfer, and exchange of Super Resolution Optical Microscope (SROM) images are inconvenient. In this work, we present an approach to standardize the SROM images based on the Digital Imaging and Communication in Medicine (DICOM) standard. The SROM images and associated information are encapsulated and converted to DICOM images based on the Visible Light Microscopic Image Information Object Definition of DICOM. The new generated SROM images in DICOM format can be displayed, processed, transferred, and exchanged by using most medical image processing tools.

  11. Singlet oxygen phosphorescence lifetime imaging based on a fluorescence lifetime imaging microscope.

    PubMed

    Tian, Wenming; Deng, Liezheng; Jin, Shengye; Yang, Heping; Cui, Rongrong; Zhang, Qing; Shi, Wenbo; Zhang, Chunlei; Yuan, Xiaolin; Sha, Guohe

    2015-04-01

    The feasibility of singlet oxygen phosphorescence (SOP) lifetime imaging microscope was studied on a modified fluorescence lifetime imaging microscope (FLIM). SOP results from the infrared radiative transition of O2(a(1)Δg → X(3)Σg(-)) and O2(a(1)Δg) was produced in a C60 powder sample via photosensitization process. To capture the very weak SOP signal, a dichroic mirror was placed between the objective and tube lens of the FLIM and used to divide the luminescence returning from the sample into two beams: the reflected SOP beam and the transmitted photoluminescence of C60 (C60-PL) beam. The C60-PL beam entered the scanner of the FLIM and followed the normal optical path of the FLIM, while the SOP steered clear of the scanner and directly entered a finely designed SOP detection channel. Confocal C60-PL images and nonconfocal SOP images were then simultaneously obtained by using laser-scanning mode. Experimental results show that (1) under laser-scanning mode, the obstacle to confocal SOP imaging is the infrared-incompatible scanner, which can be solved by using an infrared-compatible scanner. Confocal SOP imaging is also expected to be realized under stage-scanning mode when the laser beam is parked and meanwhile a pinhole is added into the SOP detection channel. (2) A great challenge to SOP imaging is its extraordinarily long imaging time, and selecting only a few interesting points from fluorescence images to measure their SOP time-dependent traces may be a correct compromise. PMID:25781060

  12. Based on spatial-temporal multiframe association infrared target detection

    NASA Astrophysics Data System (ADS)

    Wang, Zhonghua; Wang, Chao; Huang, Faliang; Liu, Jianguo

    2015-12-01

    Infrared small target detection is difficult due to several aspects, including the low signal-to-clutter ratio of the infrared image, and the small size, lack of shape and texture information of the target. a novel method, which is based on spatial-temporal association, is presented for infrared target detection. The algorithm consists of the three steps: Firstly, 2-dimensional histogram of entropy flow field is computed to estimate the background motion. Secondly, the difference image through background motion compensation is obtained. Finally, the targets are detected by spatial-temporal filter. The experiment results demonstrate that the proposed algorithm is robust to noise, and also fit to detect small targets under moving backgrounds in infrared image sequences.

  13. Infrared image enhancement based on human visual properties

    NASA Astrophysics Data System (ADS)

    Chen, Hongyu; Hui, Bin

    2015-10-01

    With the development of modern military, infrared imaging technology is widely used in this field. However, limited by the mechanism of infrared imaging and the detector, infrared images have the disadvantages of low contrast and blurry edge by comparison with the visible image. These shortcomings lead infrared image unsuitable to be observed by both human and computer. Thus image enhancement is required. Traditional image enhancement methods on the application of infrared image, without taking into account the human visual properties, is not convenient for the human observation. This article purposes a new method that combines the layering idea with the human visual properties to enhance the infrared image. The proposed method relies on bilateral filtering to separate a base component, which contains the large amplitude signal and must be compressed, from a detail component, which must be expanded because it contains the small signal variations related to fine texture. The base component is mapped into the proper range which is 8-bit using the human visual properties, and the detail component is applied the method of adaptive gain control. Finally, the two parts are recombined and quantized to 8-bit domain. Experimental results show that this algorithm exceeds most current image enhancement methods in solving the problems of low contrast and blurry detail.

  14. Determination of Base Binding Strength and Base Stacking Interaction of DNA Duplex Using Atomic Force Microscope

    PubMed Central

    Zhang, Tian-biao; Zhang, Chang-lin; Dong, Zai-li; Guan, Yi-fu

    2015-01-01

    As one of the most crucial properties of DNA, the structural stability and the mechanical strength are attracting a great attention. Here, we take advantage of high force resolution and high special resolution of Atom Force Microscope and investigate the mechanical force of DNA duplexes. To evaluate the base pair hydrogen bond strength and base stacking force in DNA strands, we designed two modes (unzipping and stretching) for the measurement rupture forces. Employing k-means clustering algorithm, the ruptured force are clustered and the mean values are estimated. We assessed the influence of experimental parameters and performed the force evaluation for DNA duplexes of pure dG/dC and dA/dT base pairs. The base binding strength of single dG/dC and single dA/dT were estimated to be 20.0 ± 0.2 pN and 14.0 ± 0.3 pN, respectively, and the base stacking interaction was estimated to be 2.0 ± 0.1 pN. Our results provide valuable information about the quantitative evaluation of the mechanical properties of the DNA duplexes. PMID:25772017

  15. An Introduction to Differentials Based on Hyperreal Numbers and Infinite Microscopes

    ERIC Educational Resources Information Center

    Henry, Valerie

    2010-01-01

    In this article, we propose to introduce the differential of a function through a non-classical way, lying on hyperreals and infinite microscopes. This approach is based on the developments of nonstandard analysis, wants to be more intuitive than the classical one and tries to emphasize the functional and geometric aspects of the differential. In…

  16. Microscope-Based Fluid Physics Experiments in the Fluids and Combustion Facility on ISS

    NASA Technical Reports Server (NTRS)

    Doherty, Michael P.; Motil, Susan M.; Snead, John H.; Malarik, Diane C.

    2000-01-01

    At the NASA Glenn Research Center, the Microgravity Science Program is planning to conduct a large number of experiments on the International Space Station in both the Fluid Physics and Combustion Science disciplines, and is developing flight experiment hardware for use within the International Space Station's Fluids and Combustion Facility. Four fluids physics experiments that require an optical microscope will be sequentially conducted within a subrack payload to the Fluids Integrated Rack of the Fluids and Combustion Facility called the Light Microscopy Module, which will provide the containment, changeout, and diagnostic capabilities to perform the experiments. The Light Microscopy Module is planned as a fully remotely controllable on-orbit microscope facility, allowing flexible scheduling and control of experiments within International Space Station resources. This paper will focus on the four microscope-based experiments, specifically, their objectives and the sample cell and instrument hardware to accommodate their requirements.

  17. Infrared super-resolution imaging based on compressed sensing

    NASA Astrophysics Data System (ADS)

    Sui, Xiubao; Chen, Qian; Gu, Guohua; Shen, Xuewei

    2014-03-01

    The theoretical basis of traditional infrared super-resolution imaging method is Nyquist sampling theorem. The reconstruction premise is that the relative positions of the infrared objects in the low-resolution image sequences should keep fixed and the image restoration means is the inverse operation of ill-posed issues without fixed rules. The super-resolution reconstruction ability of the infrared image, algorithm's application area and stability of reconstruction algorithm are limited. To this end, we proposed super-resolution reconstruction method based on compressed sensing in this paper. In the method, we selected Toeplitz matrix as the measurement matrix and realized it by phase mask method. We researched complementary matching pursuit algorithm and selected it as the recovery algorithm. In order to adapt to the moving target and decrease imaging time, we take use of area infrared focal plane array to acquire multiple measurements at one time. Theoretically, the method breaks though Nyquist sampling theorem and can greatly improve the spatial resolution of the infrared image. The last image contrast and experiment data indicate that our method is effective in improving resolution of infrared images and is superior than some traditional super-resolution imaging method. The compressed sensing super-resolution method is expected to have a wide application prospect.

  18. Infrared Image Simulation Based On Statistical Learning Theory

    NASA Astrophysics Data System (ADS)

    Chaochao, Huang; Xiaodi, Wu; Wuqin, Tong

    2007-12-01

    A real-time simulation algorithm of infrared image based on statistical learning theory is presented. The method includes three contents to achieve real-time simulation of infrared image, such as acquiring the training sample, forecasting the scene temperature field value by statistical learning machine, data processing and data analysis of temperature field. The simulation result shows this algorithm based on ν - support vector regression have better maneuverability and generalization than the other method, and the simulation precision and real-time quality are satisfying.

  19. Miniature microscope design and construction based on tilted rotationally asymmetric printed lenses

    NASA Astrophysics Data System (ADS)

    Rogers, Jeremy David

    Successful treatment of many types of cancer is improved when early detection is possible. One method of early detection is microscopic inspection of the tissue at risk. Microscopic inspection can be performed by extracting a biopsy and using traditional microscopes, but biopsy is painful and inconvenient which limits its use. An alternative is in vivo microscopy using an endoscope or microendoscopy. This dissertation describes the design, construction, and evaluation of a miniature microscope or microendoscope based on new microfabrication technologies. All components typically found in a traditional bench-top microscope were designed and built on a miniature scale. The objective was comprised of one planoconvex spherical glass lens and three printed microlenses. The printed lenses were patterned using grayscale lithography in a custom engineered photosensitive hybrid sol-gel glass material. Illumination was delivered by high-brightness Light Emitting Diodes (LEDs) via multimode fiber. The design incorporated a custom imaging detector and a Micro-Electrical-Mechanical-Systems (MEMS) actuator for optical sectioning using structured illumination. The opto-mechanical system is designed using a new concept called "zero alignment assembly" in which the lens elements snap into place and are constrained to a precise position with tolerances tighter than the optical tolerances. This scheme requires no post-assembly alignment or adjustment and simplifies system assembly. The miniature microscope was designed to image in several modes including reflectance, fluorescence, and using structured illumination for optical sectioning. A unique optical design incorporated tilted elements to remove ghost images and internal reflections from the image plane. This design enabled microscopic imaging of extremely low reflectance samples like tissue where the "in-focus" component of the object reflects only 0.04% of the illumination. The miniature microscope was built and tested by

  20. Land-based infrared imagery for marine mammal detection

    NASA Astrophysics Data System (ADS)

    Graber, Joseph; Thomson, Jim; Polagye, Brian; Jessup, Andrew

    2011-09-01

    A land-based infrared (IR) camera is used to detect endangered Southern Resident killer whales in Puget Sound, Washington, USA. The observations are motivated by a proposed tidal energy pilot project, which will be required to monitor for environmental effects. Potential monitoring methods also include visual observation, passive acoustics, and active acoustics. The effectiveness of observations in the infrared spectrum is compared to observations in the visible spectrum to assess the viability of infrared imagery for cetacean detection and classification. Imagery was obtained at Lime Kiln Park, Washington from 7/6/10-7/9/10 using a FLIR Thermovision A40M infrared camera (7.5-14μm, 37°HFOV, 320x240 pixels) under ideal atmospheric conditions (clear skies, calm seas, and wind speed 0-4 m/s). Whales were detected during both day (9 detections) and night (75 detections) at distances ranging from 42 to 162 m. The temperature contrast between dorsal fins and the sea surface ranged from 0.5 to 4.6 °C. Differences in emissivity from sea surface to dorsal fin are shown to aid detection at high incidence angles (near grazing). A comparison to theory is presented, and observed deviations from theory are investigated. A guide for infrared camera selection based on site geometry and desired target size is presented, with specific considerations regarding marine mammal detection. Atmospheric conditions required to use visible and infrared cameras for marine mammal detection are established and compared with 2008 meteorological data for the proposed tidal energy site. Using conservative assumptions, infrared observations are predicted to provide a 74% increase in hours of possible detection, compared with visual observations.

  1. Spatial resolution limits for synchrotron-based infrared spectromicroscopy

    SciTech Connect

    Levenson, Erika; Lerch, Philippe; Martin, Michael C.

    2007-10-15

    Detailed spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source synchrotron facility in Berkeley, CA. The high-brightness synchrotron source is coupled at this beamline to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests in both the mid-IR (using a KBr beamsplitter and an MCT-A* detector) and in the near-IR (using a CaF2 beamsplitter and an InGaAS detector) were performed and compared to a simple diffraction-limited spot size model. At the shorter wavelengths in the near-IR the experimental results begin to deviate from only diffraction-limited. The entire data set is fit using a combined diffraction-limit and demagnified electron beam source size model. This description experimentally verifies how the physical electron beam size of the synchrotron source demagnified to the sample stage on the endstation begins to dominate the focussed spot size and therefore spatial resolution at higher energies. We discuss how different facilities, beamlines, and microscopes will affect the achievable spatial resolution.

  2. Single-pulse CARS based multimodal nonlinear optical microscope for bioimaging.

    PubMed

    Kumar, Sunil; Kamali, Tschackad; Levitte, Jonathan M; Katz, Ori; Hermann, Boris; Werkmeister, Rene; Považay, Boris; Drexler, Wolfgang; Unterhuber, Angelika; Silberberg, Yaron

    2015-05-18

    Noninvasive label-free imaging of biological systems raises demand not only for high-speed three-dimensional prescreening of morphology over a wide-field of view but also it seeks to extract the microscopic functional and molecular details within. Capitalizing on the unique advantages brought out by different nonlinear optical effects, a multimodal nonlinear optical microscope can be a powerful tool for bioimaging. Bringing together the intensity-dependent contrast mechanisms via second harmonic generation, third harmonic generation and four-wave mixing for structural-sensitive imaging, and single-beam/single-pulse coherent anti-Stokes Raman scattering technique for chemical sensitive imaging in the finger-print region, we have developed a simple and nearly alignment-free multimodal nonlinear optical microscope that is based on a single wide-band Ti:Sapphire femtosecond pulse laser source. Successful imaging tests have been realized on two exemplary biological samples, a canine femur bone and collagen fibrils harvested from a rat tail. Since the ultra-broad band-width femtosecond laser is a suitable source for performing high-resolution optical coherence tomography, a wide-field optical coherence tomography arm can be easily incorporated into the presented multimodal microscope making it a versatile optical imaging tool for noninvasive label-free bioimaging. PMID:26074561

  3. Microscopic silicon-based lateral high-aspect-ratio structures for thin film conformality analysis

    SciTech Connect

    Gao, Feng; Arpiainen, Sanna; Puurunen, Riikka L.

    2015-01-15

    Film conformality is one of the major drivers for the interest in atomic layer deposition (ALD) processes. This work presents new silicon-based microscopic lateral high-aspect-ratio (LHAR) test structures for the analysis of the conformality of thin films deposited by ALD and by other chemical vapor deposition means. The microscopic LHAR structures consist of a lateral cavity inside silicon with a roof supported by pillars. The cavity length (e.g., 20–5000 μm) and cavity height (e.g., 200–1000 nm) can be varied, giving aspect ratios of, e.g., 20:1 to 25 000:1. Film conformality can be analyzed with the microscopic LHAR by several means, as demonstrated for the ALD Al{sub 2}O{sub 3} and TiO{sub 2} processes from Me{sub 3}Al/H{sub 2}O and TiCl{sub 4}/H{sub 2}O. The microscopic LHAR test structures introduced in this work expose a new parameter space for thin film conformality investigations expected to prove useful in the development, tuning and modeling of ALD and other chemical vapor deposition processes.

  4. Dual-mode optical microscope based on single-pixel imaging

    NASA Astrophysics Data System (ADS)

    Rodríguez, A. D.; Clemente, P.; Tajahuerce, E.; Lancis, J.

    2016-07-01

    We demonstrate an inverted microscope that can image specimens in both reflection and transmission modes simultaneously with a single light source. The microscope utilizes a digital micromirror device (DMD) for patterned illumination altogether with two single-pixel photosensors for efficient light detection. The system, a scan-less device with no moving parts, works by sequential projection of a set of binary intensity patterns onto the sample that are codified onto a modified commercial DMD. Data to be displayed are geometrically transformed before written into a memory cell to cancel optical artifacts coming from the diamond-like shaped structure of the micromirror array. The 24-bit color depth of the display is fully exploited to increase the frame rate by a factor of 24, which makes the technique practicable for real samples. Our commercial DMD-based LED-illumination is cost effective and can be easily coupled as an add-on module for already existing inverted microscopes. The reflection and transmission information provided by our dual microscope complement each other and can be useful for imaging non-uniform samples and to prevent self-shadowing effects.

  5. Identification of seven Zingiberaceous species based on comparative anatomy of microscopic characteristics of seeds

    PubMed Central

    2014-01-01

    Background The fruits and seeds of Alpinia galanga (L.) Willd., Alpinia katsumadai Hayata, Alpinia zerumbet (Pers.) Burtt. & Smith, Amomum kravanh Pierre ex Gagnep., Amomum subulatum Roxb., Amomum tsao-ko Crevost et Lemaire, and Elettaria cardamomum (L.) Maton from Alpinia, Amomum, and Elettaria genera in the Zingiberaceae family are difficult to distinguish between each other. This study aims to identify the seeds of these seven species from Zingiberaceae family based on comparative anatomy of microscopic characteristics. Methods We compared the morphological structures of seed coats by observing the microscopic characteristics of seeds in transverse sections. We described the macroscopic characteristics of seeds in detail. Results The seeds of these three genera could not be identified to the species level based on their macroscopic features. However, based on the anatomical features of the seed coat observed in transverse sections, a dichotomous key for these seven species was feasible. Conclusion Seven species in the Zingiberaceae family could be identified based on comparative anatomy of microscopic characteristics of transverse section of seed. PMID:24607026

  6. Three-dimensional positioning control based on stereo microscopic visual servoing system

    NASA Astrophysics Data System (ADS)

    Sha, Xiaopeng; Li, Huiguang; Li, Wenchao; Wang, Shuai

    2015-01-01

    A stereo microscopic system as a high-precision visual feedback is widely used in the fields of micro-three-dimensional (3-D) measurement and micromanipulation tasks. A new stereo binocular visual servoing model based on a Greenough-type stereoscopic light microscope to solve the 3-D micropositioning problem is proposed. The new model contains no depth information, but the information at the left and right images is used to obtain the image Jacobian matrix. Visual information can be directly obtained from the 3-D space without measuring or estimating the depth information of the unknown points of the object via this new model. The new model can not only accurately and rapidly realize automatic control for a micromanipulation system, but also improve the system control performance. We design an image-based controller with consideration of the kinematics characteristics of a microrobot. Experimental results verify the validity of the model.

  7. Infrared imaging using carbon nanotube-based detector

    NASA Astrophysics Data System (ADS)

    Chen, Hongzhi; Xi, Ning; Song, Bo; Chen, Liangliang; Lai, King W. C.; Lou, Jianyong

    2011-06-01

    Using carbon nanotubes (CNT), high performance infrared detectors have been developed. Since the CNTs have extraordinary optoelectronics properties due to its unique one dimensional geometry and structure, the CNT based infrared detectors have extremely low dark current, low noise equivalent temperature difference (NETD), short response time, and high dynamic range. Most importantly, it can detect 3-5 um middle-wave infrared (MWIR) at room temperature. This unique feature can significantly reduce the size and weight of a MWIR imaging system by eliminating a cryogenic cooling system. However, there are two major difficulties that impede the application of CNT based IR detectors for imaging systems. First, the small diameter of the CNTs results in low fill factor. Secondly, it is difficult to fabricate large scale of detector array for high resolution focal plane due to the limitations on the efficiency and cost of the manufacturing. In this paper, a new CNT based IR imaging system will be presented. Integrating the CNT detectors with photonic crystal resonant cavity, the fill factor of the CNT based IR sensor can reach as high as 0.91. Furthermore, using the compressive sensing technology, a high resolution imaging can be achieved by CNT based IR detectors. The experimental testing results show that the new imaging system can achieve the superb performance enabled by CNT based IR detectors, and, at the same time, overcame its difficulties to achieve high resolution and efficient imaging.

  8. 3D micropositioning control based on stereo microscopic visual servoing system

    NASA Astrophysics Data System (ADS)

    Sha, Xiaopeng; Li, Huiguang; Wang, Shuai; Li, Zhiquan; Li, Guoyou

    2014-08-01

    In this paper, the global visual servoing micropositioning control method is analyzed and the imaging model is derived based on the CMO type stereo light microscopes (SLM). The model contains no depth information and the left and right image information is used to obtain the image Jacobian matrix. Considering the kinematics characteristics of micro robot, we design an image-based controller. The experimental and simulation results based on the four degree-offreedom (DOF) microrobot system demonstrate the validity of the theory in this paper.

  9. Infrared imaging spectroscopic system based on a PGP spectrograph and a monochrome infrared camera

    NASA Astrophysics Data System (ADS)

    Garcia-Allende, Pilar Beatriz; Anabitarte, Francisco; Conde, Olga M.; Madruga, Francisco J.; Lomer, Mauro; Lopez-Higuera, Jose M.

    2008-04-01

    Hyperspectral imaging spectroscopy has been widely used in remote sensing. However, its potential for applications in industrial and biological fields is enormous. Observation line spectrographs, based on the reflectance of the material under study in each field, can be obtained by means of an imaging spectrometer. In this way, imaging spectroscopy allows the simultaneous determination of the optical spectrum components and the spatial location of an object in a surface. A simple, small and low-cost spectrometer, such as those ones based on passive Prism-Grating-Prism (PGP) devices, is required for the abovementioned application fields. In this paper a non-intrusive and non-contact near infrared acquisition system based on a PGP spectrometer is presented. An extension to the whole near infrared range of the spectrum of a previously designed system in the Vis-NIR range has been performed. The reason under this investigation is to improve material characterization. To our knowledge, no imaging spectroscopic system based on a PGP device working in this range has been previously reported. The components of the system, its assembling, alignment and calibration procedures will be described in detail. This system can be generalized for a wide variety of applications employing a specific and adequate data processing

  10. Application of local gene induction by infrared laser-mediated microscope and temperature stimulator to amphibian regeneration study.

    PubMed

    Kawasumi-Kita, Aiko; Hayashi, Toshinori; Kobayashi, Takuya; Nagayama, Chikashi; Hayashi, Shinichi; Kamei, Yasuhiro; Morishita, Yoshihiro; Takeuchi, Takashi; Tamura, Koji; Yokoyama, Hitoshi

    2015-12-01

    Urodele amphibians (newts and salamanders) and anuran amphibians (frogs) are excellent research models to reveal mechanisms of three-dimensional organ regeneration since they have exceptionally high regenerative capacity among tetrapods. However, the difficulty in manipulating gene expression in cells in a spatially restricted manner has so far hindered elucidation of the molecular mechanisms of organ regeneration in amphibians. Recently, local heat shock by laser irradiation has enabled local gene induction even at the single-cell level in teleost fishes, nematodes, fruit flies and plants. In this study, local heat shock was made with infrared laser irradiation (IR-LEGO) by using a gene expression inducible system in transgenic animals containing a heat shock promoter, and gene expression was successfully induced only in the target region of two amphibian species, Xenopus laevis and Pleurodeles waltl (a newt), at postembryonic stages. Furthermore, we induced spatially restricted but wider gene expression in Xenopus laevis tadpoles and froglets by applying local heat shock by a temperature-controlled metal probe (temperature stimulator). The local gene manipulation systems, the IR-LEGO and the temperature stimulator, enable us to do a rigorous cell lineage trace with the combination of the Cre-LoxP system as well as to analyze gene function in a target region or cells with less off-target effects in the study of amphibian regeneration. PMID:26510480

  11. The technology of forest fire detection based on infrared image

    NASA Astrophysics Data System (ADS)

    Wu, Zhi-guo; Liu, Guo-juan; Wang, Ming-jia; Wang, Suo-jian

    2013-09-01

    According to infrared imaging features of forest fire, we use image processing technology which is conducive to early detection and prevention of forest fires. We use image processing technology based on infrared imaging features of forest fire which is conducive to early detection and prevention of forest fires. In order to the timeliness and accuracy of fire detection, this paper proposes a forest fire detection method based on infrared image technology. We take gray histogram analysis to collected Cruising image. The image which will be detected is segmented by the adaptive dynamic threshold. Then the suspected ignitions are extracted in the image after segmentation. The ignition of forest fire which form image in the infrared image is almost circular. We use the circular degree of suspected ignition as the decision basis of the fire in the infrared image. Through the analysis of position correlation which is the same suspected ignition between adjacent frames, we judge whether there is a fire in the image. In order to verify the effectiveness of the method, we adopt image sequences of forest fire to do experiment. The experimental results show that the proposed algorithm under the conditions of different light conditions and complex backgrounds, which can effectively eliminate distractions and extract the fire target. The accuracy fire detection rate is above 95 percent. All fire can be detected. The method can quickly identify fire flame and high-risk points of early fire. The structure of method is clear and efficient which processing speed is less than 25 frames per second. So it meets the application requirement of real-time processing.

  12. Feedback and injection locking instabilities in quantum-dot lasers: a microscopically based bifurcation analysis

    NASA Astrophysics Data System (ADS)

    Lingnau, Benjamin; Chow, Weng W.; Schöll, Eckehard; Lüdge, Kathy

    2013-09-01

    We employ a nonequilibrium energy balance and carrier rate equation model based on microscopic semiconductor theory to describe the quantum-dot (QD) laser dynamics under optical injection and time-delayed feedback. The model goes beyond typical phenomenological approximations of rate equations, such as the α-factor, yet allows for a thorough numerical bifurcation analysis, which would not be possible with the computationally demanding microscopic equations. We find that with QD lasers, independent amplitude and phase dynamics may lead to less complicated scenarios under optical perturbations than predicted by conventional models using the α-factor to describe the carrier-induced refractive index change. For instance, in the short external cavity feedback regime, higher critical feedback strength is actually required to induce instabilities. Generally, the α-factor should only be used when the carrier distribution can follow the QD laser dynamics adiabatically.

  13. Inexpensive Monocular Pico-Projector-based Augmented Reality Display for Surgical Microscope

    PubMed Central

    Shi, Chen; Becker, Brian C.; Riviere, Cameron N.

    2013-01-01

    This paper describes an inexpensive pico-projector-based augmented reality (AR) display for a surgical microscope. The system is designed for use with Micron, an active handheld surgical tool that cancels hand tremor of surgeons to improve microsurgical accuracy. Using the AR display, virtual cues can be injected into the microscope view to track the movement of the tip of Micron, show the desired position, and indicate the position error. Cues can be used to maintain high performance by helping the surgeon to avoid drifting out of the workspace of the instrument. Also, boundary information such as the view range of the cameras that record surgical procedures can be displayed to tell surgeons the operation area. Furthermore, numerical, textual, or graphical information can be displayed, showing such things as tool tip depth in the work space and on/off status of the canceling function of Micron. PMID:25264542

  14. Long-wave infrared polarimetric cluster-based vehicle detection.

    PubMed

    Dickson, Christopher N; Wallace, Andrew M; Kitchin, Matthew; Connor, Barry

    2015-12-01

    The sensory perception of other vehicles in cluttered environments is an essential component of situational awareness for a mobile vehicle. However, vehicle detection is normally applied to visible imagery sequences, while in this paper we investigate how polarized, infrared imagery can add additional discriminatory power. Using knowledge about the properties of the objects of interest and the scene environment, we have developed a polarimetric cluster-based descriptor to detect vehicles using long-wave infrared radiation in the range of 8-12 μm. Our approach outperforms both intensity and polarimetric image histogram descriptors applied to the infrared data. For example, at a false positive rate of 0.01 per detection window, our cluster approach results in a true positive rate of 0.63 compared to a rate of 0.05 for a histogram of gradient descriptor trained and tested on the same dataset. In conclusion, we discuss the potential of this new approach in comparison with state-of-the-art infrared and conventional video detection. PMID:26831384

  15. Automated cervical precancerous cells screening system based on Fourier transform infrared spectroscopy features

    NASA Astrophysics Data System (ADS)

    Jusman, Yessi; Mat Isa, Nor Ashidi; Ng, Siew-Cheok; Hasikin, Khairunnisa; Abu Osman, Noor Azuan

    2016-07-01

    Fourier transform infrared (FTIR) spectroscopy technique can detect the abnormality of a cervical cell that occurs before the morphological change could be observed under the light microscope as employed in conventional techniques. This paper presents developed features extraction for an automated screening system for cervical precancerous cell based on the FTIR spectroscopy as a second opinion to pathologists. The automated system generally consists of the developed features extraction and classification stages. Signal processing techniques are used in the features extraction stage. Then, discriminant analysis and principal component analysis are employed to select dominant features for the classification process. The datasets of the cervical precancerous cells obtained from the feature selection process are classified using a hybrid multilayered perceptron network. The proposed system achieved 92% accuracy.

  16. A new generation of mid-infrared sensors based on quantum cascade laser

    NASA Astrophysics Data System (ADS)

    Dey, Dibyendu; Kohoutek, John; Gelfand, Ryan M.; Bonakder, Alireza; Mohseni, Hooman

    2011-05-01

    Many important bio and chemical molecules have their signature frequency (vibrational resonance) matching the mid infrared region (2-10 μm) of the optical spectrum. But building a bio-sensor, sensitive in this spectral regime, is extremely challenging task. It is because of the weak light-particle interaction strength due to huge dimensional mismatch between the probed molecules (typically ~ 10's of nm) and the probing wavelength (order of micron). We exploit the optical antenna to overcome this problem by squeezing the optical modes. This modal confinement happens only in the near-field region of the antenna and thus we have built an apertureless near-field scanning optical microscope (a-NSOM) to demonstrate it experimentally. Further, we have integrated these plasmonic antennas with mid-infrared sources known as Quantum Cascade Lasers (QCL). Our antenna structure is based on metal-dielectric-metal (MDM) and we have shown how they can generate higher electrical field enhancement compared to single metal design. Antenna integrated QCL operated at room temperature and its wavelength of operation was measured to be ~ 6μm. We have used 3D finite-difference-time-domain (FDTD) simulations to optimize the different component of the MDM antenna. After optimizing, we fabricated the antenna on the facet of QCL using focused ion beam (FIB) and measured using a-NSOM. We have shown that the optical mode can be squeezed down to a few 100's of nm which is much smaller than the incident light wavelength (λ~6μm). We also propose a microfluidic approach to build a typical mid-infrared bio-sensor where the probed molecules can be transferred to the near field region of the antenna through fluidic channels. Such scheme of building bio-sensor can overcome the barrier of weak light-particle interaction and eventually could lead to building very efficient, compact, mid-infrared bio-sensors.

  17. Field programmable gate array based reconfigurable scanning probe/optical microscope.

    PubMed

    Nowak, Derek B; Lawrence, A J; Dzegede, Zechariah K; Hiester, Justin C; Kim, Cliff; Sánchez, Erik J

    2011-10-01

    The increasing popularity of nanometrology and nanospectroscopy has pushed researchers to develop complex new analytical systems. This paper describes the development of a platform on which to build a microscopy tool that will allow for flexibility of customization to suit research needs. The novelty of the described system lies in its versatility of capabilities. So far, one version of this microscope has allowed for successful near-field and far-field fluorescence imaging with single molecule detection sensitivity. This system is easily adapted for reflection, polarization (Kerr magneto-optical (MO)), Raman, super-resolution techniques, and other novel scanning probe imaging and spectroscopic designs. While collecting a variety of forms of optical images, the system can simultaneously monitor topographic information of a sample with an integrated tuning fork based shear force system. The instrument has the ability to image at room temperature and atmospheric pressure or under liquid. The core of the design is a field programmable gate array (FPGA) data acquisition card and a single, low cost computer to control the microscope with analog control circuitry using off-the-shelf available components. A detailed description of electronics, mechanical requirements, and software algorithms as well as examples of some different forms of the microscope developed so far are discussed. PMID:22047297

  18. Plasmons in molecules: Microscopic characterization based on orbital transitions and momentum conservation

    SciTech Connect

    Krauter, Caroline M.; Schirmer, Jochen; Pernpointner, Markus; Jacob, Christoph R.; Dreuw, Andreas

    2014-09-14

    In solid state physics, electronic excitations are often classified as plasmons or single-particle excitations. The former class of states refers to collective oscillations of the electron density. The random-phase approximation allows for a quantum-theoretical treatment and a characterization on a microscopic level as a coherent superposition of a large number of particle-hole transitions with the same momentum transfer. However, small systems such as molecules or small nanoclusters lack the basic properties (momentum conservation and uniform exchange interaction) responsible for the formation of plasmons in the solid-state case. Despite an enhanced interest in plasmon-based technologies and an increasing number of studies regarding plasmons in molecules and small nanoclusters, their definition on a microscopic level of theory remains ambiguous. In this work, we analyze the microscopic properties of molecular plasmons in comparison with the homogeneous electron gas as a model system. Subsequently, the applicability of the derived characteristics is validated by analyzing the electronic excitation vectors with respect to orbital transitions for two linear polyenes within second order versions of the algebraic diagrammatic construction scheme for the polarization propagator.

  19. Field programmable gate array based reconfigurable scanning probe/optical microscope

    NASA Astrophysics Data System (ADS)

    Nowak, Derek B.; Lawrence, A. J.; Dzegede, Zechariah K.; Hiester, Justin C.; Kim, Cliff; Sánchez, Erik J.

    2011-10-01

    The increasing popularity of nanometrology and nanospectroscopy has pushed researchers to develop complex new analytical systems. This paper describes the development of a platform on which to build a microscopy tool that will allow for flexibility of customization to suit research needs. The novelty of the described system lies in its versatility of capabilities. So far, one version of this microscope has allowed for successful near-field and far-field fluorescence imaging with single molecule detection sensitivity. This system is easily adapted for reflection, polarization (Kerr magneto-optical (MO)), Raman, super-resolution techniques, and other novel scanning probe imaging and spectroscopic designs. While collecting a variety of forms of optical images, the system can simultaneously monitor topographic information of a sample with an integrated tuning fork based shear force system. The instrument has the ability to image at room temperature and atmospheric pressure or under liquid. The core of the design is a field programmable gate array (FPGA) data acquisition card and a single, low cost computer to control the microscope with analog control circuitry using off-the-shelf available components. A detailed description of electronics, mechanical requirements, and software algorithms as well as examples of some different forms of the microscope developed so far are discussed.

  20. Plasmons in molecules: microscopic characterization based on orbital transitions and momentum conservation.

    PubMed

    Krauter, Caroline M; Schirmer, Jochen; Jacob, Christoph R; Pernpointner, Markus; Dreuw, Andreas

    2014-09-14

    In solid state physics, electronic excitations are often classified as plasmons or single-particle excitations. The former class of states refers to collective oscillations of the electron density. The random-phase approximation allows for a quantum-theoretical treatment and a characterization on a microscopic level as a coherent superposition of a large number of particle-hole transitions with the same momentum transfer. However, small systems such as molecules or small nanoclusters lack the basic properties (momentum conservation and uniform exchange interaction) responsible for the formation of plasmons in the solid-state case. Despite an enhanced interest in plasmon-based technologies and an increasing number of studies regarding plasmons in molecules and small nanoclusters, their definition on a microscopic level of theory remains ambiguous. In this work, we analyze the microscopic properties of molecular plasmons in comparison with the homogeneous electron gas as a model system. Subsequently, the applicability of the derived characteristics is validated by analyzing the electronic excitation vectors with respect to orbital transitions for two linear polyenes within second order versions of the algebraic diagrammatic construction scheme for the polarization propagator. PMID:25217898

  1. eSIP: A Novel Solution-Based Sectioned Image Property Approach for Microscope Calibration

    PubMed Central

    Butzlaff, Malte; Weigel, Arwed; Ponimaskin, Evgeni; Zeug, Andre

    2015-01-01

    Fluorescence confocal microscopy represents one of the central tools in modern sciences. Correspondingly, a growing amount of research relies on the development of novel microscopic methods. During the last decade numerous microscopic approaches were developed for the investigation of various scientific questions. Thereby, the former qualitative imaging methods became replaced by advanced quantitative methods to gain more and more information from a given sample. However, modern microscope systems being as complex as they are, require very precise and appropriate calibration routines, in particular when quantitative measurements should be compared over longer time scales or between different setups. Multispectral beads with sub-resolution size are often used to describe the point spread function and thus the optical properties of the microscope. More recently, a fluorescent layer was utilized to describe the axial profile for each pixel, which allows a spatially resolved characterization. However, fabrication of a thin fluorescent layer with matching refractive index is technically not solved yet. Therefore, we propose a novel type of calibration concept for sectioned image property (SIP) measurements which is based on fluorescent solution and makes the calibration concept available for a broader number of users. Compared to the previous approach, additional information can be obtained by application of this extended SIP chart approach, including penetration depth, detected number of photons, and illumination profile shape. Furthermore, due to the fit of the complete profile, our method is less susceptible to noise. Generally, the extended SIP approach represents a simple and highly reproducible method, allowing setup independent calibration and alignment procedures, which is mandatory for advanced quantitative microscopy. PMID:26244982

  2. eSIP: A Novel Solution-Based Sectioned Image Property Approach for Microscope Calibration.

    PubMed

    Butzlaff, Malte; Weigel, Arwed; Ponimaskin, Evgeni; Zeug, Andre

    2015-01-01

    Fluorescence confocal microscopy represents one of the central tools in modern sciences. Correspondingly, a growing amount of research relies on the development of novel microscopic methods. During the last decade numerous microscopic approaches were developed for the investigation of various scientific questions. Thereby, the former qualitative imaging methods became replaced by advanced quantitative methods to gain more and more information from a given sample. However, modern microscope systems being as complex as they are, require very precise and appropriate calibration routines, in particular when quantitative measurements should be compared over longer time scales or between different setups. Multispectral beads with sub-resolution size are often used to describe the point spread function and thus the optical properties of the microscope. More recently, a fluorescent layer was utilized to describe the axial profile for each pixel, which allows a spatially resolved characterization. However, fabrication of a thin fluorescent layer with matching refractive index is technically not solved yet. Therefore, we propose a novel type of calibration concept for sectioned image property (SIP) measurements which is based on fluorescent solution and makes the calibration concept available for a broader number of users. Compared to the previous approach, additional information can be obtained by application of this extended SIP chart approach, including penetration depth, detected number of photons, and illumination profile shape. Furthermore, due to the fit of the complete profile, our method is less susceptible to noise. Generally, the extended SIP approach represents a simple and highly reproducible method, allowing setup independent calibration and alignment procedures, which is mandatory for advanced quantitative microscopy. PMID:26244982

  3. Infrared Sensor-Based Temperature Control for Domestic Induction Cooktops

    PubMed Central

    Lasobras, Javier; Alonso, Rafael; Carretero, Claudio; Carretero, Enrique; Imaz, Eduardo

    2014-01-01

    In this paper, a precise real-time temperature control system based on infrared (IR) thermometry for domestic induction cooking is presented. The temperature in the vessel constitutes the control variable of the closed-loop power control system implemented in a commercial induction cooker. A proportional-integral controller is applied to establish the output power level in order to reach the target temperature. An optical system and a signal conditioning circuit have been implemented. For the signal processing a microprocessor with 12-bit ADC and a sampling rate of 1 Ksps has been used. The analysis of the contributions to the infrared radiation permits the definition of a procedure to estimate the temperature of the vessel with a maximum temperature error of 5 °C in the range between 60 and 250 °C for a known cookware emissivity. A simple and necessary calibration procedure with a black-body sample is presented. PMID:24638125

  4. Testing smooth surface characteristics based on thermal infrared polarization

    NASA Astrophysics Data System (ADS)

    Sun, Li; Wang, Zhen; Hong, Jin; Qiao, Yan-li; Chen, Yi-qiong

    2007-12-01

    A novel optical method was provided to test the sample surface using a thermal polarimeter. The polarimeter consists of a rotary polarization filter and a thermal imaging system that is based on an uncooled focal plane array (UFPA) in long wave infrared (LWIR, 8~12μm) band. The thermal infrared polarization images of a Vernier caliper head were taken by a rotary polarizing filter at angles of 0°, 60°, 120° degrees. These images were saved into a computer and were calculated with Stokes parameter formulas to produce digital images of Stokes parameters I, Q and U, degree of linear polarization and direction of polarization. These images clearly show the difference between different areas of Vernier caliper, and this difference is not obtainable from the intensity images. Experimental results show that the introduced method can extract surface roughness information from thermal images and can distinguish different surface characteristics quickly.

  5. Method of narcissus analysis in infrared system based on ASAP

    NASA Astrophysics Data System (ADS)

    Ren, Guodong; Zhang, Liang; Lan, Weihua; Pan, Xiaodong

    2015-11-01

    Narcissus of cooled infrared system should be controlled strictly. So, accurate and rapid analysis of narcissus is very important. Deriving the SNR of narcissus based on the definition of noise equivalent power. Using simulation software CodeV and ASAP analyses the narcissus. Screen out the optical surface whose narcissus is serious in CodeV. Then build the model of the system in ASAP and add reasonable surface properties, get the result of size and average irradiance of the image narcissus spot by real ray tracing. Calculate the SNR of narcissus by putting the value of average irradiance into front formulation. On this basis, the simulation analysis and experimental test about the Narcissus of an infrared lens were performed. The experimental result is consistent with the simulation analysis.

  6. Infrared transparent frequency selective surface based on metallic meshes

    SciTech Connect

    Yu, Miao; Xu, Nianxi; Liu, Hai; Gao, Jinsong

    2014-02-15

    This paper presents an infrared transparent frequency selective surface (ITFSS) based on metallic meshes. In this ITFSS structure, periodic cross-slot units are integrated on square metallic meshes empowered by coating and UV-lithography. A matching condition is proposed to avoid the distortion of units. Experimental results show that this ITFSS possesses a good transmittance of 80% in the infrared band of 3–5 μm, and also a stable band-pass behavior at the resonance frequency of 36.4 GHz with transmittance of −0.56 dB. Theoretical simulations about the ITFSS diffractive characteristics and frequency responses are also investigated. The novel ITFSS will attract renewed interest and be exploited for applications in various fields.

  7. Comparative study on submillimeter flaws in stitched T-joint carbon fiber reinforced polymer by infrared thermography, microcomputed tomography, ultrasonic c-scan and microscopic inspection

    NASA Astrophysics Data System (ADS)

    Zhang, Hai; Hassler, Ulf; Genest, Marc; Fernandes, Henrique; Robitaille, Francois; Ibarra-Castanedo, Clemente; Joncas, Simon; Maldague, Xavier

    2015-10-01

    Stitching is used to reduce dry-core (incomplete infusion of T-joint core) and reinforce T-joint structure. However, it may cause new types of flaws, especially submillimeter flaws. Microscopic inspection, ultrasonic c-scan, pulsed thermography, vibrothermography, and laser spot thermography are used to investigate the internal flaws in a stitched T-joint carbon fiber-reinforced polymer (CFRP) matrix composites. Then, a new microlaser line thermography is proposed. Microcomputed tomography (microCT) is used to validate the infrared results. A comparison between microlaser line thermography and microCT is performed. It was concluded that microlaser line thermography can detect the internal submillimeter defects. However, the depth and size of the defects can affect the detection results. The microporosities with a diameter of less than 54 μm are not detected in the microlaser line thermography results. Microlaser line thermography can detect the microporosity (a diameter of 0.162 mm) from a depth of 90 μm. However, it cannot detect the internal microporosity (a diameter of 0.216 mm) from a depth of 0.18 mm. The potential causes are given. Finally, a comparative study is conducted.

  8. The variable refractive index correction algorithm based on a stereo light microscope

    NASA Astrophysics Data System (ADS)

    Pei, W.; Zhu, Y. Y.

    2010-02-01

    Refraction occurs at least twice on both the top and the bottom surfaces of the plastic plate covering the micro channel in a microfluidic chip. The refraction and the nonlinear model of a stereo light microscope (SLM) may severely affect measurement accuracy. In this paper, we study the correlation between optical paths of the SLM and present an algorithm to adjust the refractive index based on the SLM. Our algorithm quantizes the influence of cover plate and double optical paths on the measurement accuracy, and realizes non-destructive, non-contact and precise 3D measurement of a hyaloid and closed container.

  9. Inorganic resist materials based on zirconium phosphonate for atomic force microscope lithography

    NASA Astrophysics Data System (ADS)

    Kang, Mankyu; Kim, Seonae; Jung, JinHyuck; Kim, Heebom; Shin, Inkyun; Jeon, Chanuk; Lee, Haiwon

    2014-03-01

    New inorganic resist materials based on metal complexes were investigated for atomic force microscope (AFM) lithography. Phosphoric acids are good for self-assembly because of their strong binding energy. In this work, zirconium phosphonate system are newly synthesized for spin-coatable materials in aqueous solutions and leads to negative tone pattern for improving line edge roughness. Low electron exposure by AFM lithography could generate a pattern by electrochemical reaction and cross-linking of metal-oxo complexes. It has been reported that the minimum pattern results are affected by lithographic speed, and the applied voltage between a tip and a substrate.

  10. Simultaneous measurement of normal and friction forces using a cantilever-based optical interfacial force microscope

    NASA Astrophysics Data System (ADS)

    Kim, Byung I.; Bonander, Jeremy R.; Rasmussen, Jared A.

    2011-05-01

    We measured normal and friction forces simultaneously using a recently developed cantilever-based optical interfacial force microscope technique for studies of interfacial structures and mechanical properties of nanoscale materials. We derived how the forces can be incorporated into the detection signal using the classical Euler equation for beams. A lateral modulation with the amplitude of nanometers was applied to create the friction forces between tip and sample. We demonstrated its capability by measuring normal and friction forces of interfacial water at the molecular scale over all distance ranges.

  11. Simultaneous measurement of normal and friction forces using a cantilever-based optical interfacial force microscope.

    PubMed

    Kim, Byung I; Bonander, Jeremy R; Rasmussen, Jared A

    2011-05-01

    We measured normal and friction forces simultaneously using a recently developed cantilever-based optical interfacial force microscope technique for studies of interfacial structures and mechanical properties of nanoscale materials. We derived how the forces can be incorporated into the detection signal using the classical Euler equation for beams. A lateral modulation with the amplitude of nanometers was applied to create the friction forces between tip and sample. We demonstrated its capability by measuring normal and friction forces of interfacial water at the molecular scale over all distance ranges. PMID:21639511

  12. Improved motion information-based infrared dim target tracking algorithms

    NASA Astrophysics Data System (ADS)

    Lei, Liu; Zhijian, Huang

    2014-11-01

    Accurate and fast tracking of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. However, under complex backgrounds, such as clutter, varying illumination, and occlusion, the traditional tracking method often converges to a local maximum and loses the real infrared target. To cope with these problems, three improved tracking algorithm based on motion information are proposed in this paper, namely improved mean shift algorithm, improved Optical flow method and improved Particle Filter method. The basic principles and the implementing procedure of these modified algorithms for target tracking are described. Using these algorithms, the experiments on some real-life IR and color images are performed. The whole algorithm implementing processes and results are analyzed, and those algorithms for tracking targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying tracking effectiveness and robustness. Meanwhile, it has high tracking efficiency and can be used for real-time tracking.

  13. Texture orientation-based algorithm for detecting infrared maritime targets.

    PubMed

    Wang, Bin; Dong, Lili; Zhao, Ming; Wu, Houde; Xu, Wenhai

    2015-05-20

    Infrared maritime target detection is a key technology for maritime target searching systems. However, in infrared maritime images (IMIs) taken under complicated sea conditions, background clutters, such as ocean waves, clouds or sea fog, usually have high intensity that can easily overwhelm the brightness of real targets, which is difficult for traditional target detection algorithms to deal with. To mitigate this problem, this paper proposes a novel target detection algorithm based on texture orientation. This algorithm first extracts suspected targets by analyzing the intersubband correlation between horizontal and vertical wavelet subbands of the original IMI on the first scale. Then the self-adaptive wavelet threshold denoising and local singularity analysis of the original IMI is combined to remove false alarms further. Experiments show that compared with traditional algorithms, this algorithm can suppress background clutter much better and realize better single-frame detection for infrared maritime targets. Besides, in order to guarantee accurate target extraction further, the pipeline-filtering algorithm is adopted to eliminate residual false alarms. The high practical value and applicability of this proposed strategy is backed strongly by experimental data acquired under different environmental conditions. PMID:26192503

  14. Adaptation of a Fortran-Based Monte-Carlo Microscopic Black Hole Simulation Program to C++ Based Root

    NASA Astrophysics Data System (ADS)

    Jenkins, C. M.; Godang, R.; Cavaglia, M.; Cremaldi, L.; Summers, D.

    2008-10-01

    The 14 TeV center of mass proton-proton collisions at the LHC opens the possibility for new Physics, including the possible formation of microscopic black holes. A Fortran-based Monte Carlo event generator program called CATFISH (Collider grAviTational FIeld Simulator for black Holes) has been developed at the University of Mississippi to study signatures of microscopic black hole production (http://www.phy.olemiss.edu/GR/catfish). This black hole event generator includes many of the currently accepted theoretical results for microscopic black hole formation. High energy physics data analysis is shifting from Fortran to C++ as the CERN data analysis packages HBOOK and PAW are no longer supported. The C++ based root is replacing these packages. Work done at the University of South Alabama has resulted in a successful inclusion of CATFISH into root. The methods used to interface the Fortran-based CATFISH into the C++ based root will be presented. Benchmark histograms will be presented demonstrating the conversion. Preliminary results will be presented for selecting black hole candidate events in 14 TeV/ center of mass proton-proton collisions.

  15. Graphene-based platform for nano-scale infrared near-field spectroscopy of biological materials

    NASA Astrophysics Data System (ADS)

    Khatib, Omar; Wood, Joshua D.; Doidge, Gregory P.; Damhorst, Gregory L.; Rangarajan, Aniruddh; Bashir, Rashid; Pop, Eric; Lyding, Joseph W.; Basov, Dimitri N.

    2014-03-01

    In biological and life sciences, Fourier Transform Infrared (FTIR) spectroscopy serves as a noninvasive probe of vibrational fingerprints used to identify chemical and molecular species. Near-field spectroscopy, based on the illumination of an atomic force microscope (AFM) tip with an infrared laser, allows for determination of IR properties of a material at nanometer length scales. However, application of near-field IR spectroscopy to most biological systems has thus far been elusive. Physiological conditions required for experimentation are incompatible with typical implementations of nano-FTIR. Recently it became possible to trap water and small biomolecules underneath large-area graphene sheets grown by chemical vapor deposition (CVD). The graphene layer serves as an IR-transparent cover that allows for a near-field interrogation of the underlying layers. We present near-field nano-imaging and spectroscopy data of unencapsulated Tobacco Mosaic Viruses (TMV), compared to those sandwiched between two large-area graphene sheets, and discuss the applicability of near-field IR spectroscopy to trapped biomolecules in aqueous environments.

  16. Image distortion correction for micromanipulation system based on SLM microscopic vision.

    PubMed

    Wang, Yuezong; Jin, Yan; Wang, Lika

    2016-03-01

    Stereo light microscope (SLM) simulates stereo imaging principle of human eyes. Microscopic vision system based on SLM has become an important visual tool for micro measurement, micromanipulation, and microinjection. We develop a micromanipulation system based on SLM and present an image distortion correction method. We mainly correct two kinds of image distortions: lateral and vertical distortion. Distortion correction consists of two steps. First, a linear fitting algorithm for each row or column of target points is developed, and the fitting errors are calculated. If the fitting errors are smaller than a given threshold, the linear fitting results are kept and used. Otherwise polynomial fitting procedure will be used. Second, the parallelism of straight lines is corrected. The results show that a line in world coordinate frame (WCF) is not necessarily a straight line in image coordinate frame (ICF), or two parallel lines in WCF may be not parallel in ICF. Distortion correction can restore the parallel and linear relationship. For distorted left and right images, the magnitude of distortion exceeds 6 pixels and 4 pixels in the horizontal direction, and 1.2 pixels and 1.7 pixels in the vertical direction, respectively. After corrected, for left and right image, distortion can be reduced to 0.8 pixels and 0.7 pixels in the horizontal direction, and 0.96 pixels and 1.3 pixels in the vertical direction, respectively. The results show that distortion parameters obtained from the proposed method can effectively correct distorted images. PMID:26789139

  17. Affine calibration based on invariable extrinsic parameters for stereo light microscope

    NASA Astrophysics Data System (ADS)

    Li, Weixian; Wei, Zhenzhong; Zhang, Guangjun

    2014-10-01

    The stereo light microscope (SLM) plays an important role in the measurement of three-dimensional geometry on the microscopic scale. We propose a fast and precise affine calibration algorithm based on the invariable extrinsic parameters for the SLM. This calibration algorithm with a free planar reference consists of three steps: first, derive the extrinsic parameters based on their invariable definition in the pinhole and affine models; second, calculate the intrinsic parameters through homography matrix; finally, refine all the model parameters by global optimization with the previous closed-form solutions as the initial values. The effectiveness of assuming a noncoaxial optical system as an affine camera is also verified to affinely model all types of SLMs. The calibration experiments show that the affine calibration is preferable for multicriteria including running time, relative positioning precision, and absolute positioning precision. With PlanApo S 1.5× and a total magnification of 3.024×, the proposed affine calibration algorithm achieves a distance error of 0.423 μm and a positioning error of 0.195 mm within 10.6 s.

  18. An infrared image based methodology for breast lesions screening

    NASA Astrophysics Data System (ADS)

    Morais, K. C. C.; Vargas, J. V. C.; Reisemberger, G. G.; Freitas, F. N. P.; Oliari, S. H.; Brioschi, M. L.; Louveira, M. H.; Spautz, C.; Dias, F. G.; Gasperin, P.; Budel, V. M.; Cordeiro, R. A. G.; Schittini, A. P. P.; Neto, C. D.

    2016-05-01

    The objective of this paper is to evaluate the potential of utilizing a structured methodology for breast lesions screening, based on infrared imaging temperature measurements of a healthy control group to establish expected normality ranges, and of breast cancer patients, previously diagnosed through biopsies of the affected regions. An analysis of the systematic error of the infrared camera skin temperature measurements was conducted in several different regions of the body, by direct comparison to high precision thermistor temperature measurements, showing that infrared camera temperatures are consistently around 2 °C above the thermistor temperatures. Therefore, a method of conjugated gradients is proposed to eliminate the infrared camera direct temperature measurement imprecision, by calculating the temperature difference between two points to cancel out the error. The method takes into account the human body approximate bilateral symmetry, and compares measured dimensionless temperature difference values (Δ θ bar) between two symmetric regions of the patient's breast, that takes into account the breast region, the surrounding ambient and the individual core temperatures, and doing so, the results interpretation for different individuals become simple and non subjective. The range of normal whole breast average dimensionless temperature differences for 101 healthy individuals was determined, and admitting that the breasts temperatures exhibit a unimodal normal distribution, the healthy normal range for each region was considered to be the dimensionless temperature difference plus/minus twice the standard deviation of the measurements, Δ θ bar ‾ + 2σ Δ θ bar ‾ , in order to represent 95% of the population. Forty-seven patients with previously diagnosed breast cancer through biopsies were examined with the method, which was capable of detecting breast abnormalities in 45 cases (96%). Therefore, the conjugated gradients method was considered effective

  19. Infrared imaging based hyperventilation monitoring through respiration rate estimation

    NASA Astrophysics Data System (ADS)

    Basu, Anushree; Routray, Aurobinda; Mukherjee, Rashmi; Shit, Suprosanna

    2016-07-01

    A change in the skin temperature is used as an indicator of physical illness which can be detected through infrared thermography. Thermograms or thermal images can be used as an effective diagnostic tool for monitoring and diagnosis of various diseases. This paper describes an infrared thermography based approach for detecting hyperventilation caused due to stress and anxiety in human beings by computing their respiration rates. The work employs computer vision techniques for tracking the region of interest from thermal video to compute the breath rate. Experiments have been performed on 30 subjects. Corner feature extraction using Minimum Eigenvalue (Shi-Tomasi) algorithm and registration using Kanade Lucas-Tomasi algorithm has been used here. Thermal signature around the extracted region is detected and subsequently filtered through a band pass filter to compute the respiration profile of an individual. If the respiration profile shows unusual pattern and exceeds the threshold we conclude that the person is stressed and tending to hyperventilate. Results obtained are compared with standard contact based methods which have shown significant correlations. It is envisaged that the thermal image based approach not only will help in detecting hyperventilation but can assist in regular stress monitoring as it is non-invasive method.

  20. New deconvolution method for microscopic images based on the continuous Gaussian radial basis function interpolation model

    NASA Astrophysics Data System (ADS)

    Chen, Zhaoxue; Chen, Hao

    2014-07-01

    A deconvolution method based on the Gaussian radial basis function (GRBF) interpolation is proposed. Both the original image and Gaussian point spread function are expressed as the same continuous GRBF model, thus image degradation is simplified as convolution of two continuous Gaussian functions, and image deconvolution is converted to calculate the weighted coefficients of two-dimensional control points. Compared with Wiener filter and Lucy-Richardson algorithm, the GRBF method has an obvious advantage in the quality of restored images. In order to overcome such a defect of long-time computing, the method of graphic processing unit multithreading or increasing space interval of control points is adopted, respectively, to speed up the implementation of GRBF method. The experiments show that based on the continuous GRBF model, the image deconvolution can be efficiently implemented by the method, which also has a considerable reference value for the study of three-dimensional microscopic image deconvolution.

  1. High vacuum tip-enhanced Raman spectroscope based on a scanning tunneling microscope.

    PubMed

    Fang, Yurui; Zhang, Zhenglong; Sun, Mengtao

    2016-03-01

    In this paper, we present the construction of a high-vacuum tip-enhanced Raman spectroscopy (HV-TERS) system that allows in situ sample preparation and measurement. A detailed description of the prototype instrument is presented with experimental validation of its use and novel ex situ experimental results using the HV-TERS system. The HV-TERS system includes three chambers held under a 10(-7) Pa vacuum. The three chambers are an analysis chamber, a sample preparation chamber, and a fast loading chamber. The analysis chamber is the core chamber and contains a scanning tunneling microscope (STM) and a Raman detector coupled with a 50 × 0.5 numerical aperture objective. The sample preparation chamber is used to produce single-crystalline metal and sub-monolayer molecular films by molecular beam epitaxy. The fast loading chamber allows ex situ preparation of samples for HV-TERS analysis. Atomic resolution can be achieved by the STM on highly ordered pyrolytic graphite. We demonstrate the measurement of localized temperature using the Stokes and anti-Stokes TERS signals from a monolayer of 1,2-benzenedithiol on a gold film using a gold tip. Additionally, plasmonic catalysis can be monitored label-free at the nanoscale using our device. Moreover, the HV-TERS experiments show simultaneously activated infrared and Raman vibrational modes, Fermi resonance, and some other non-linear effects that are not observed in atmospheric TERS experiments. The high spatial and spectral resolution and pure environment of high vacuum are beneficial for basic surface studies. PMID:27036755

  2. High vacuum tip-enhanced Raman spectroscope based on a scanning tunneling microscope

    NASA Astrophysics Data System (ADS)

    Fang, Yurui; Zhang, Zhenglong; Sun, Mengtao

    2016-03-01

    In this paper, we present the construction of a high-vacuum tip-enhanced Raman spectroscopy (HV-TERS) system that allows in situ sample preparation and measurement. A detailed description of the prototype instrument is presented with experimental validation of its use and novel ex situ experimental results using the HV-TERS system. The HV-TERS system includes three chambers held under a 10-7 Pa vacuum. The three chambers are an analysis chamber, a sample preparation chamber, and a fast loading chamber. The analysis chamber is the core chamber and contains a scanning tunneling microscope (STM) and a Raman detector coupled with a 50 × 0.5 numerical aperture objective. The sample preparation chamber is used to produce single-crystalline metal and sub-monolayer molecular films by molecular beam epitaxy. The fast loading chamber allows ex situ preparation of samples for HV-TERS analysis. Atomic resolution can be achieved by the STM on highly ordered pyrolytic graphite. We demonstrate the measurement of localized temperature using the Stokes and anti-Stokes TERS signals from a monolayer of 1,2-benzenedithiol on a gold film using a gold tip. Additionally, plasmonic catalysis can be monitored label-free at the nanoscale using our device. Moreover, the HV-TERS experiments show simultaneously activated infrared and Raman vibrational modes, Fermi resonance, and some other non-linear effects that are not observed in atmospheric TERS experiments. The high spatial and spectral resolution and pure environment of high vacuum are beneficial for basic surface studies.

  3. A scanning measurement method of the pitch of grating based on photoelectric microscope

    NASA Astrophysics Data System (ADS)

    Gao, Hongtang; Wang, Zhongyu; Wang, Hao

    2015-10-01

    Grating is an important sensor widely used in CNC machine or equipment for length measurement with high precision. Special line scales with dense and micro lines are also widely used for the calibration of length measurement instrument. All the pitches of grating and spaces of dense lines of line scale are needed to be calibrated for a good measurement application. General methods for measurement of dense and micro lines include digital image processing method by CCD Microscope or line scanning method by AFM or SEM, and laser distraction method. There are some disadvantages to measure a long length grating with high precision and efficiently in these methods. A dynamic method based on Photoelectric Microscope is introduced, the lines of grating to be measured is moving uniformly when measuring, and the working distance is a bigger 65mm, the zoom of objective is low 10X. The principle of this dynamic method is discussed and the distortion of line signal is analyzed. The way to decrease the affection caused by distortion of line signal is also described. A special glass grating line scale with length 10mm, space 10μm and width 5μm is measured to verify the method. The measurement result and the uncertainty analysis demonstrate the expand measurement uncertainty (k=2) is less than 0.1μm.

  4. Single-spin microscope with sub-nanoscale resolution based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P; Chernobrod, Boris

    2009-01-01

    Invention of scanning tunneling microscope (STM) and atomic force microscope (AFM) initiated a new era of material science and technology characterized by 2-D imaging with atomic resolution and manipulation of individual atoms. However, for further progress in material science, and in particular in structural biology, 3-D imaging with sub-nanometer resolution is very desirable. Currently the most promising technique for 3-D imaging is magnetic resonance force microscopy (MRFM), which senses individual electron spins [1,2] with nanoscale resolution and can detect collective magnetization of about 100 nuclear spins [3]. The highest sensitivity demonstrated by MRFM is based on a time modulation technique called the oscillating cantilever-driven adiabatic reversals (OSCAAR) which requires a long phase relaxation time T 2 of measured spins, which usually corresponds to rather low temperature. For example, a temperature of 300 mK was used in the case of 3D imaging of the tobacco mosaic virus [3]. This limitation is incompatible with the room-temperature operation needed for the study of biological systems under physiological conditions.

  5. Vertical scanning white light interfering profilometer based on Linnik interference microscope

    NASA Astrophysics Data System (ADS)

    Wang, Shuzhen; Xie, Tiebang; Chang, Suping

    2010-10-01

    In this paper we provide a vertical scanning white light interfering profilometer based on Linnik type interference microscope. A vertical scanning system with coarse-fine dual-stage actuators is developed, in which the coarse positioning is performed by inclined sliding guides, AC servo motor, ballscrew and the fine positioning is performed by parallel board flexure hinge and piezoelectric ceramic, respectively. The displacement range of the vertical scanning system is 0~2mm and 0.4nm theoretical motion resolution can be achieved. The whole interference microscope of the profilometer is driven by the vertical scanning system, which will eliminate the movement coupling error of vertical direction caused by horizontal movement of 2D precision stage. The interference fringes or the focal plane can be automatically located by moving the vertical scanning system. To eliminate the measurement errors of the profilometer caused by incorrect positioning of the vertical scanning system, its displacement is measured in real-time by a laser interferometer with theoretical resolution of 0.01nm. A single groove specimen with the depth of 1.26μm calibrated by National Institute of Metrology P.R.China, MEMS device and textured steel sheet was measured to illustrate the capabilities of the profilometer.

  6. Defects evaluation system for spherical optical surfaces based on microscopic scattering dark-field imaging method.

    PubMed

    Zhang, Yihui; Yang, Yongying; Li, Chen; Wu, Fan; Chai, Huiting; Yan, Kai; Zhou, Lin; Li, Yang; Liu, Dong; Bai, Jian; Shen, Yibing

    2016-08-10

    In the field of automatic optical inspection, it is imperative to measure the defects on spherical optical surfaces. So a novel spherical surface defect evaluation system is established in this paper to evaluate defects on optical spheres. In order to ensure the microscopic scattering dark-field imaging of optical spheres with different surface shape and radius of curvature, illumination with variable aperture angle is employed. In addition, the scanning path of subapertures along the parallels and meridians is planned to detect the large optical spheres. Since analysis shows that the spherical defect information could be lost in the optical imaging, the three-dimensional correction based on a pin-hole model is proposed to recover the actual spherical defects from the captured two-dimensional images. Given the difficulty of subaperture stitching and defect feature extraction in three-dimensional (3D) space after the correction, the 3D subapertures are transformed into a plane to be spliced through geometric projection. Then, methods of the surface integral and calibration are applied to quantitatively evaluate the spherical defects. Furthermore, the 3D panorama of defect distribution on the spherical optical components can be displayed through the inverse projective reconstruction. Finally, the evaluation results are compared with the OLYMPUS microscope, testifying to the micrometer resolution, and the detection error is less than 5%. PMID:27534456

  7. Multi-element double ring infrared detector based on InSb

    NASA Astrophysics Data System (ADS)

    Li, Mo; Lv, Hui; Guo, Li; Liu, Zhu

    2015-10-01

    A multi-element double ring infrared detector based on InSb p-n photodiodes is presented. The presented detector includes an outer ring detector and an inner ring detector. Each ring consist 10 detector elements, five mid-wave infrared detector elements and five short wave infrared detector elements. Two wavebands of 3.5-5 μm and 1.5-3 μm in mid-wave infrared and short wave infrared are adopted. The mid-wave infrared and short wave infrared detector elements are arranged alternately and close to each other to form detection pair. Between the adjacent detector elements, there is an interval to avoid cross talk. Dual band filter thin films are directly coated on the photodiode surface to form a dual band infrared detector. The double ring detector which can perform dual band IR counter-countermeasures can track target effectively under infrared countermeasure conditions.

  8. Ambient temperature normalization for infrared face recognition based on the second-order polynomial model

    NASA Astrophysics Data System (ADS)

    Wang, Zhengzi

    2015-08-01

    The influence of ambient temperature is a big challenge to robust infrared face recognition. This paper proposes a new ambient temperature normalization algorithm to improve the performance of infrared face recognition under variable ambient temperatures. Based on statistical regression theory, a second order polynomial model is learned to describe the ambient temperature's impact on infrared face image. Then, infrared image was normalized to reference ambient temperature by the second order polynomial model. Finally, this normalization method is applied to infrared face recognition to verify its efficiency. The experiments demonstrate that the proposed temperature normalization method is feasible and can significantly improve the robustness of infrared face recognition.

  9. Photoacoustic-based detector for infrared laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Scholz, L.; Palzer, S.

    2016-07-01

    In this contribution, we present an alternative detector technology for use in direct absorption spectroscopy setups. Instead of a semiconductor based detector, we use the photoacoustic effect to gauge the light intensity. To this end, the target gas species is hermetically sealed under excess pressure inside a miniature cell along with a MEMS microphone. Optical access to the cell is provided by a quartz window. The approach is particularly suitable for tunable diode laser spectroscopy in the mid-infrared range, where numerous molecules exhibit large absorption cross sections. Moreover, a frequency standard is integrated into the method since the number density and pressure inside the cell are constant. We demonstrate that the information extracted by our method is at least equivalent to that achieved using a semiconductor-based photon detector. As exemplary and highly relevant target gas, we have performed direct spectroscopy of methane at the R3-line of the 2v3 band at 6046.95 cm-1 using both detector technologies in parallel. The results may be transferred to other infrared-active transitions without loss of generality.

  10. Infrared imaging-based combat casualty care system

    NASA Astrophysics Data System (ADS)

    Davidson, James E., Sr.

    1997-08-01

    A Small Business Innovative Research (SBIR) contract was recently awarded to a start up company for the development of an infrared (IR) image based combat casualty care system. The company, Medical Thermal Diagnostics, or MTD, is developing a light weight, hands free, energy efficient uncooled IR imaging system based upon a Texas Instruments design which will allow emergency medical treatment of wounded soldiers in complete darkness without any type of light enhancement equipment. The principal investigator for this effort, Dr. Gene Luther, DVM, Ph.D., Professor Emeritus, LSU School of Veterinary Medicine, will conduct the development and testing of this system with support from Thermalscan, Inc., a nondestructive testing company experienced in IR thermography applications. Initial research has been done with surgery on a cat for feasibility of the concept as well as forensic research on pigs as a close representation of human physiology to determine time of death. Further such studies will be done later as well as trauma studies. IR images of trauma injuries will be acquired by imaging emergency room patients to create an archive of emergency medical situations seen with an infrared imaging camera. This archived data will then be used to develop training material for medical personnel using the system. This system has potential beyond military applications. Firefighters and emergency medical technicians could directly benefit from the capability to triage and administer medical care to trauma victims in low or no light conditions.

  11. Learning-based compressed sensing for infrared image super resolution

    NASA Astrophysics Data System (ADS)

    Zhao, Yao; Sui, Xiubao; Chen, Qian; Wu, Shaochi

    2016-05-01

    This paper presents an infrared image super-resolution method based on compressed sensing (CS). First, the reconstruction model under the CS framework is established and a Toeplitz matrix is selected as the sensing matrix. Compared with traditional learning-based methods, the proposed method uses a set of sub-dictionaries instead of two coupled dictionaries to recover high resolution (HR) images. And Toeplitz sensing matrix allows the proposed method time-efficient. Second, all training samples are divided into several feature spaces by using the proposed adaptive k-means classification method, which is more accurate than the standard k-means method. On the basis of this approach, a complex nonlinear mapping from the HR space to low resolution (LR) space can be converted into several compact linear mappings. Finally, the relationships between HR and LR image patches can be obtained by multi-sub-dictionaries and HR infrared images are reconstructed by the input LR images and multi-sub-dictionaries. The experimental results show that the proposed method is quantitatively and qualitatively more effective than other state-of-the-art methods.

  12. Enabling scanning electron microscope contour-based optical proximity correction models

    NASA Astrophysics Data System (ADS)

    Weisbuch, François; Jantzen, Kenneth

    2015-04-01

    A scanning electron microscope (SEM) is the metrology tool used to accurately characterize very fine structures on wafers, usually by extracting one critical dimension (CD) per SEM image. This approach for optical proximity correction (OPC) modeling requires many measurements resulting in a lengthy cycle time for data collection, review, and cleaning, and faces reliability issues when dealing with critical two-dimensional (2-D) structures. An alternative to CD-based metrology is to use SEM image contours for OPC modeling. To calibrate OPC models with contours, reliable contours matched to traditional CD-SEM measurements are required along with a method to choose structure and site selections (number, type, and image space coverage) specific to a contour-based OPC model calibration. The potential of SEM contour model-based calibration is illustrated by comparing two contour-based models to reference models, one empirical model and a second rigorous simulation-based model. The contour-based models are as good as or better than a CD-based model with a significant advantage in the prediction of complex 2-D configurations with a reduced metrology work load.

  13. Scattering assisted injection based injectorless mid infrared quantum cascade laser

    SciTech Connect

    Singh, Siddharth Kamoua, Ridha

    2014-06-07

    An injectorless five-well mid infrared quantum cascade laser is analyzed which relies on phonon scattering injection in contrast to resonant tunneling injection, which has been previously used for injectorless designs. A Monte Carlo based self-consistent electron and photon transport simulator is used to analyze the performance of the analyzed design and compare it to existing injectorless designs. The simulation results show that the analyzed design could greatly enhance the optical gain and the characteristic temperatures of injectorless quantum cascade lasers (QCLs) which have typically been hindered by low characteristic temperatures and significant temperature related performance degradation. Simulations of the analyzed device predict threshold current densities of 0.85 kA/cm{sup 2} and 1.95 kA/cm{sup 2} at 77 K and 300 K, respectively, which are comparable to the threshold current densities of conventional injector based QCLs.

  14. Infrared small target detection based on Danger Theory

    NASA Astrophysics Data System (ADS)

    Lan, Jinhui; Yang, Xiao

    2009-11-01

    To solve the problem that traditional method can't detect the small objects whose local SNR is less than 2 in IR images, a Danger Theory-based model to detect infrared small target is presented in this paper. First, on the analog with immunology, the definition is given, in this paper, to such terms as dangerous signal, antigens, APC, antibodies. Besides, matching rule between antigen and antibody is improved. Prior to training the detection model and detecting the targets, the IR images are processed utilizing adaptive smooth filter to decrease the stochastic noise. Then at the training process, deleting rule, generating rule, crossover rule and the mutation rule are established after a large number of experiments in order to realize immediate convergence and obtain good antibodies. The Danger Theory-based model is built after the training process, and this model can detect the target whose local SNR is only 1.5.

  15. Research of infrared laser based pavement imaging and crack detection

    NASA Astrophysics Data System (ADS)

    Hong, Hanyu; Wang, Shu; Zhang, Xiuhua; Jing, Genqiang

    2013-08-01

    Road crack detection is seriously affected by many factors in actual applications, such as some shadows, road signs, oil stains, high frequency noise and so on. Due to these factors, the current crack detection methods can not distinguish the cracks in complex scenes. In order to solve this problem, a novel method based on infrared laser pavement imaging is proposed. Firstly, single sensor laser pavement imaging system is adopted to obtain pavement images, high power laser line projector is well used to resist various shadows. Secondly, the crack extraction algorithm which has merged multiple features intelligently is proposed to extract crack information. In this step, the non-negative feature and contrast feature are used to extract the basic crack information, and circular projection based on linearity feature is applied to enhance the crack area and eliminate noise. A series of experiments have been performed to test the proposed method, which shows that the proposed automatic extraction method is effective and advanced.

  16. Compression of multispectral fluorescence microscopic images based on a modified set partitioning in hierarchal trees

    NASA Astrophysics Data System (ADS)

    Mansoor, Awais; Robinson, J. Paul; Rajwa, Bartek

    2009-02-01

    Modern automated microscopic imaging techniques such as high-content screening (HCS), high-throughput screening, 4D imaging, and multispectral imaging are capable of producing hundreds to thousands of images per experiment. For quick retrieval, fast transmission, and storage economy, these images should be saved in a compressed format. A considerable number of techniques based on interband and intraband redundancies of multispectral images have been proposed in the literature for the compression of multispectral and 3D temporal data. However, these works have been carried out mostly in the elds of remote sensing and video processing. Compression for multispectral optical microscopy imaging, with its own set of specialized requirements, has remained under-investigated. Digital photography{oriented 2D compression techniques like JPEG (ISO/IEC IS 10918-1) and JPEG2000 (ISO/IEC 15444-1) are generally adopted for multispectral images which optimize visual quality but do not necessarily preserve the integrity of scientic data, not to mention the suboptimal performance of 2D compression techniques in compressing 3D images. Herein we report our work on a new low bit-rate wavelet-based compression scheme for multispectral fluorescence biological imaging. The sparsity of signicant coefficients in high-frequency subbands of multispectral microscopic images is found to be much greater than in natural images; therefore a quad-tree concept such as Said et al.'s SPIHT1 along with correlation of insignicant wavelet coefficients has been proposed to further exploit redundancy at high-frequency subbands. Our work propose a 3D extension to SPIHT, incorporating a new hierarchal inter- and intra-spectral relationship amongst the coefficients of 3D wavelet-decomposed image. The new relationship, apart from adopting the parent-child relationship of classical SPIHT, also brought forth the conditional "sibling" relationship by relating only the insignicant wavelet coefficients of subbands

  17. Efficient alignment scheme for zone-plates-based transmission soft X-ray microscope

    NASA Astrophysics Data System (ADS)

    Lim, Jun; Shin, Hyun-Joon; Hong, Chung Ki

    2010-12-01

    Alignment and operation of a zone-plate (ZP)-based transmission soft X-ray microscope (TXM) is difficult and time consuming, especially when the TXM has no dedicated X-ray source. We introduce here an efficient TXM alignment scheme. The TXM employed is a simple in-situ-experiment-capable setup. It includes ultrahigh-vacuum (UHV)-compatible conflat flanges and is mountable in tandem with any soft X-ray synchrotron radiation beamlines. Obtaining zeroth- and first-order diffracted (condenser-zone-plate [CZP]-focused) beams simultaneously by means of the objective zone plate (OZP) is the most essential step in the alignment scheme. We were able to acquire, in one hour at a radiation wavelength of 2.49 nm, an image of 50 nm spatial resolution.

  18. A depth estimation method based on geometric transformation for stereo light microscope.

    PubMed

    Fan, Shengli; Yu, Mei; Wang, Yigang; Jiang, Gangyi

    2014-01-01

    Stereo light microscopes (SLM) with narrow vision and shallow depth of field are widely used in micro-domain research. In this paper, we propose a depth estimation method of micro objects based on geometric transformation. By analyzing the optical imaging geometry, the definition of geometric transformation distance is given and the depth-distance relation express is obtained. The parameters of geometric transformation and express are calibrated with calibration board images captured in aid of precise motorized stage. The depth of micro object can be estimated by calculating the geometric transformation distance. The proposed depth-distance relation express is verified using an experiment in which the depth map of an Olanzapine tablet surface is reconstructed. PMID:25226979

  19. SPY: a new scission-point model based on microscopic inputs to predict fission fragment properties

    NASA Astrophysics Data System (ADS)

    Panebianco, Stefano; Dubray, Nöel; Goriely, Stéphane; Hilaire, Stéphane; Lemaître, Jean-François; Sida, Jean-Luc

    2014-04-01

    Despite the difficulty in describing the whole fission dynamics, the main fragment characteristics can be determined in a static approach based on a so-called scission-point model. Within this framework, a new Scission-Point model for the calculations of fission fragment Yields (SPY) has been developed. This model, initially based on the approach developed by Wilkins in the late seventies, consists in performing a static energy balance at scission, where the two fragments are supposed to be completely separated so that their macroscopic properties (mass and charge) can be considered as fixed. Given the knowledge of the system state density, averaged quantities such as mass and charge yields, mean kinetic and excitation energy can then be extracted in the framework of a microcanonical statistical description. The main advantage of the SPY model is the introduction of one of the most up-to-date microscopic descriptions of the nucleus for the individual energy of each fragment and, in the future, for their state density. These quantities are obtained in the framework of HFB calculations using the Gogny nucleon-nucleon interaction, ensuring an overall coherence of the model. Starting from a description of the SPY model and its main features, a comparison between the SPY predictions and experimental data will be discussed for some specific cases, from light nuclei around mercury to major actinides. Moreover, extensive predictions over the whole chart of nuclides will be discussed, with particular attention to their implication in stellar nucleosynthesis. Finally, future developments, mainly concerning the introduction of microscopic state densities, will be briefly discussed.

  20. Protective infrared antireflection coating based on sputtered germanium carbide

    NASA Astrophysics Data System (ADS)

    Gibson, Des; Waddell, Ewan; Placido, Frank

    2011-09-01

    This paper describes optical, durablility and environmental performance of a germanium carbide based durable antireflection coating. The coating has been demonstrated on germanium and zinc selenide infra-red material however is applicable to other materials such as zinc sulphide. The material is deposited using a novel reactive closed field magnetron sputtering technique, offering significant advantages over conventional evaporation processes for germanium carbide such as plasma enhanced chemical vapour deposition. The sputtering process is "cold", making it suitable for use on a wide range of substrates. Moreover, the drum format provide more efficient loading for high throughput production. The use of the closed field and unbalanced magnetrons creates a magnetic confinement that extends the electron mean free path leading to high ion current densities. The combination of high current densities with ion energies in the range ~30eV creates optimum thin film growth conditions. As a result the films are dense, spectrally stable, supersmooth and low stress. Films incorporate low hydrogen content resulting in minimal C-H absorption bands within critical infra-red passbands such as 3 to 5um and 8 to 12um. Tuning of germanium carbide (Ge(1-x)Cx) film refractive index from pure germanium (refractive index 4) to pure germanium carbide (refractive index 1.8) will be demonstrated. Use of film grading to achieve single and dual band anti-reflection performance will be shown. Environmental and durability levels are shown to be suitable for use in harsh external environments.

  1. Infrared near-field imaging and spectroscopy based on thermal or synchrotron radiation

    SciTech Connect

    Peragut, Florian; De Wilde, Yannick; Brubach, Jean-Blaise; Roy, Pascale

    2014-06-23

    We demonstrate the coupling of a scattering near-field scanning optical microscope combined with a Fourier transform infrared spectrometer. The set-up operates using either the near-field thermal emission from the sample itself, which is proportional to the electromagnetic local density of states, or with an external infrared synchrotron source, which is broadband and highly brilliant. We perform imaging and spectroscopy measurements with sub-wavelength spatial resolution in the mid-infrared range on surfaces made of silicon carbide and gold and demonstrate the capabilities of the two configurations for super-resolved near-field mid-infrared hyperspectral imaging and that the simple use of a properly chosen bandpass filter on the detector allows one to image the spatial distribution of materials with sub-wavelength resolution by studying the contrast in the near-field images.

  2. Infrared micro- and nano-spectroscopy of carbon-based materials

    NASA Astrophysics Data System (ADS)

    Khatib, Omar

    The following dissertation explores the low-energy physics and infrared properties associated with a suite of organic and molecular materials. The majority of the work is centered around organic semiconductors, specifically conducting polymers. First, we explore a novel method of charge injection in organic semiconductors involving exposure to vapors of fluorinated organosilane molecules. We show that ultra-high carrier densities in the range 10 14 cm-2 are attainable, a regime that is inaccessable by conventional oxide-based electrostatic field-effect. Further, we provide spectroscopic evidence of delocalized states and thus metallic transport, signaling that such highly-doped polymer films are at the threshold of the metal-insulator transition, an area of both high academic and practical interest. The next two sections explore a new class of narrow bandgap donor-acceptor (DA) copolymers, based on benzobisthiadiazole (BBT) and diketopyrrolopyrrole (DPP), that demonstrate intrinsic ambipolarity when integrated in field-effect transistors. We perform a systematic infrared investigation of thin film transistors based on DA copolymers. We study the electronic excitations under both positive and negative gate biases, to determine the electron- and hole-induced IR spectral features. For high-mobility polymer films based on DPP, we observe distinct polaronic absorption features associated with both electrons and holes. We employ a customized diffraction-limited IR microscope to study the evolution of the electronic response throughout the channel of a functional field-effect transistor device. From the strength of the IR absorptions, we are able to map the carrier density across the conduction channel. When biased at moderate gate biases in the 'ambipolar regime' where electrons and holes coexist in the channel, we register the transition from electron-polaron to hole-polaron IR absorption as a function of position. The last section explores an entirely new concept in

  3. Blind restoration method of three-dimensional microscope image based on RL algorithm

    NASA Astrophysics Data System (ADS)

    Yao, Jin-li; Tian, Si; Wang, Xiang-rong; Wang, Jing-li

    2013-08-01

    Thin specimens of biological tissue appear three dimensional transparent under a microscope. The optic slice images can be captured by moving the focal planes at the different locations of the specimen. The captured image has low resolution due to the influence of the out-of-focus information comes from the planes adjacent to the local plane. Using traditional methods can remove the blur in the images at a certain degree, but it needs to know the point spread function (PSF) of the imaging system accurately. The accuracy degree of PSF influences the restoration result greatly. In fact, it is difficult to obtain the accurate PSF of the imaging system. In order to restore the original appearance of the specimen under the conditions of the imaging system parameters are unknown or there is noise and spherical aberration in the system, a blind restoration methods of three-dimensional microscope based on the R-L algorithm is proposed in this paper. On the basis of the exhaustive study of the two-dimension R-L algorithm, according to the theory of the microscopy imaging and the wavelet transform denoising pretreatment, we expand the R-L algorithm to three-dimension space. It is a nonlinear restoration method with the maximum entropy constraint. The method doesn't need to know the PSF of the microscopy imaging system precisely to recover the blur image. The image and PSF converge to the optimum solutions by many alterative iterations and corrections. The matlab simulation and experiments results show that the expansion algorithm is better in visual indicators, peak signal to noise ratio and improved signal to noise ratio when compared with the PML algorithm, and the proposed algorithm can suppress noise, restore more details of target, increase image resolution.

  4. Infrared Fibers for Use in Space-Based Smart Structures

    NASA Technical Reports Server (NTRS)

    Tucker, Dennis S.; Nettles, Alan T.; Brantley, Lott W. (Technical Monitor)

    2001-01-01

    Infrared optical fibers are finding a number of applications including laser surgery, remote sensing, and nuclear radiation resistant links. Utilizing these fibers in space-based structures is another application, which can be exploited. Acoustic and thermal sensing are two areas in which these fibers could be utilized. In particular, fibers could be embedded in IM7/8552 toughened epoxy and incorporated into space structures both external and internal. ZBLAN optical fibers are a candidate, which have been studied extensively over the past 20 years for terrestrial applications. For the past seven years the effects of gravity on the crystallization behavior of ZBLAN optical fiber has been studied. It has been found that ZBLAN crystallization is suppressed in microgravity. This lack of crystallization leads to a fiber with better transmission characteristics than its terrestrial counterpart.

  5. Optical-based spectral modeling of infrared focal plane arrays

    NASA Astrophysics Data System (ADS)

    Mouzali, Salima; Lefebvre, Sidonie; Rommeluère, Sylvain; Ferrec, Yann; Primot, Jérôme

    2016-07-01

    We adopt an optical approach in order to model and predict the spectral signature of an infrared focal plane array. The modeling is based on a multilayer description of the structure and considers a one-dimensional propagation. It provides a better understanding of the physical phenomena occurring within the pixels, which is useful to perform radiometric measurements, as well as to reliably predict the spectral sensitivity of the detector. An exhaustive model is presented, covering the total spectral range of the pixel response. A heuristic model is also described, depicting a complementary approach that separates the different optical phenomena inside the pixel structure. Promising results are presented, validating the models through comparison with experimental results. Finally, advantages and limitations of this approach are discussed.

  6. An infrared radiation based thermal biosensor for enzymatic biochemical reactions.

    PubMed

    Zhang, Lei; Dong, Tao; Zhao, Xinyan; Yang, Zhaochu; Pires, Nuno M M

    2012-01-01

    In this paper, a thermal biosensor based on the infrared radiation energy is proposed for calorimetric measurement of biochemical reactions. Having a good structure design combined with MEMS technology as well as employing the Si /SiGe quantum well sensing material with a high TCR and low 1/f noise, the sensor shows potentials to be high sensitive and real-time. The urea enzymatic reaction was tested to verify the performance of sensor, which demonstrates a linear detection range from 0.5mM to 150mM and a relative standard deviation less than 1%. For the sensor fabrication, wafer-level transfer bonding is a key process, which makes the integration of quantum well material and a free standing structure possible. It reduces the heat loss from the sensor to the surrounding environment. PMID:23365944

  7. Infrared frequency standard based on magnetically trapped NH molecules

    SciTech Connect

    Kajita, Masatoshi

    2006-09-15

    An infrared frequency standard based on the NH |n{sub v}=0,N{sub 0}=0,J=1,F{sub 1}=3/2,F=5/2,M{sub F}=5/2>{yields}|n{sub v}=1,N{sub 0}=0,J=1,F{sub 1}=3/2,F=5/2,M{sub F}== 5/2> transition (3 {mu}m) is proposed. There is no Zeeman shift with this transition frequency, because the Zeeman coefficient is not dependent on the vibrational state. NH molecules, precooled by collisions with liquid {sup 3}He vapor, are trapped by an inhomogeneous magnetic field. The temperature of the trapped NH molecules holds the potential to be reduced down to several {mu}K by evaporative cooling. The uncertainty of the clock transition can potentially be reduced to lower than 10{sup -17}.

  8. Active Shape Model-Based Gait Recognition Using Infrared Images

    NASA Astrophysics Data System (ADS)

    Kim, Daehee; Lee, Seungwon; Paik, Joonki

    We present a gait recognition system using infra-red (IR) images. Since an IR camera is not affected by the intensity of illumination, it is able to provide constant recognition performance regardless of the amount of illumination. Model-based object tracking algorithms enable robust tracking with partial occlusions or dynamic illumination. However, this algorithm often fails in tracking objects if strong edge exists near the object. Replacement of the input image by an IR image guarantees robust object region extraction because background edges do not affect the IR image. In conclusion, the proposed gait recognition algorithm improves accuracy in object extraction by using IR images and the improvements finally increase the recognition rate of gaits.

  9. Gas emission analysis based on Fourier transformed infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Shu, Xiaowen; Zhang, Xiaofu; Lian, Xu; Jin, Hui

    2014-12-01

    Solar occultation flux (SOF), a new optical technology to detect the gas based on the traditional Fourier transformed infrared spectroscopy (FTIR) developed quickly recently. In this paper, the system and the data analysis is investigated. First a multilayer transmission model of solar radiation is simulated. Then the retrieval process is illustrated. In the proceeding of the data analysis, the Levenberg-Marquardt non-linear square fitting is used to obtain the gas column concentration and the related emission ratio. After the theory certification, the built up system is conducted in a fertilizer plant in Hefei city .The results show SOF is available in the practice and the retrieved gas column concentration can give important information about the pollution emission and dispersion

  10. Progress report towards a digital mirror device based confocal microscopic system

    NASA Astrophysics Data System (ADS)

    Yi, Dingrong; Lin, Shunhua; Huang, Simian; Xie, Shaochuan

    2013-12-01

    It is widely believed that by using a digital mirror device (DMD) as the spatial light modulator (SLM) of a programmable array microcopy (PAM), it is possible to achieve a cost-effective alternative to expensive confocal imaging devices. During the past decade, the design of such a DMD based PAM instrument has been frequently reported to enhance resolution and contrast, convincing images with improved quality are rare to be seen. The concrete implementation of a DMD based PAM instrument needs to successfully resolve multiple issues such as the adverse effects caused by the tilt angle of the micro-mirrors from the base board, the registration between a micro mirror of the DMD and the image pixel of the photo-detector and so on. In this paper, we report the design of a middle body consisting of a DMD as an independent attachment to a conventional microscope to convert the latter into a confocal imaging system, in a similar way as a filter turret that is placed below the head and the objectives of a regular microscopy to convert it into a fluorescent microscopy. Images of real objects with improved contrast are provided to demonstrate the effectiveness of using a DMD as SLM to improve the contrast of a PAM instrument. Such a PAM instrument has many advantages compared to conventional laser-scanning confocal systems including lower costs and higher imaging speeds. In addition, it allows convenient dynamic adjustments between imaging quality and imaging speed.

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

  12. Universal framework for temperature dependence prediction of the negative bias temperature instability based on microscope pictures

    NASA Astrophysics Data System (ADS)

    Ma, Chenyue; Zhang, Lining; Lin, Xinnan; Chan, Mansun

    2016-04-01

    A universal framework for describing the temperature enhanced negative bias temperature instability (NBTI) is developed in this paper. Analytical time evolution models of the NBTI mechanisms, as Pb center generation and hole-transport in the oxygen vacancies, are proposed based on careful investigation of atom-level microscopic pictures. A logarithmic time function is derived to describe the interface state (Pb center) generation and recovery evolution by revealing a fact that the activation energy is significantly modified by the accumulation of generated defects. Corresponding coefficients, including the generation amplitudes and time constant, are identified depending on temperature linearly and exponentially. Moreover, the unrecoverable oxide hole-trapping is proposed resulted from the hole-transport among deep-level oxygen vacancies driven by electrical field within the gate oxide. A power-law time function is derived to describing this evolution, with time exponent linear to temperature. Parameters calculated by the proposed analytical models reveal good consistent with the parameters directly extracted from the measured data, indicating the validation and universality of the physical based framework in reproducing the parametric shift of the NBTI degradation under various temperature conditions and process technologies.

  13. A novel, microscope based, non invasive Laser Doppler flowmeter for choroidal blood flow assessment

    PubMed Central

    Strohmaier, C; Werkmeister, RM; Bogner, B; Runge, C; Schroedl, F; Brandtner, H; Radner, W; Schmetterer, L; Kiel, JW; Grabnerand, G; Reitsamer, HA

    2015-01-01

    Impaired ocular blood flow is involved in the pathogenesis of numerous ocular diseases like glaucoma or AMD. The purpose of the present study was to introduce and validate a novel, microscope based, non invasive laser Doppler flowmeter (NILDF) for measurement of blood flow in the choroid. The custom made NI-LDF was compared with a commercial fiber optic based laser Doppler flowmeter (Perimed PF4000). Linearity and stability of the NI-LDF were assessed in a silastic tubing model (i.d. 0.3 mm) at different flow rates (range 0.4 – 3 ml/h). In a rabbit model continuous choroidal blood flow measurements were performed with both instruments simultaneously. During blood flow measurements ocular perfusion pressure was changed by manipulations of intraocular pressure via intravitreal saline infusions. The NILDF measurement correlated linearly to intraluminal flow rates in the perfused tubing model (r = 0.99, p<0.05) and remained stable during a 1 hour measurement at a constant flow rate. Rabbit choroidal blood flow measured by the PF4000 and the NI-LDF linearly correlated with each other over the entire measurement range (r = 0.99, y = x* 1,01 – 12,35 P.U., p < 0,001). In conclusion, the NI-LDF provides valid, semi quantitative measurements of capillary blood flow in comparison to an established LDF instrument and is suitable for measurements at the posterior pole of the eye. PMID:21443871

  14. Broadband dielectric characterization of aqueous saline solutions by an interferometer-based microwave microscope

    NASA Astrophysics Data System (ADS)

    Gu, Sijia; Lin, Tianjun; Lasri, Tuami

    2016-06-01

    The complex dielectric permittivity of aqueous saline solutions has been determined in the frequency range [2-18 GHz] with a home-made near-field microwave microscope. The instrument is built on a vector network analyzer, a matching network, and an evanescent microwave probe. The interferometer-based matching network enables highly reproducible, sensitive, and accurate measurements on the entire frequency band of operation. NaCl solutions concentrations ranging from 0 to 160 mg/ml are investigated at 25 °C. A maximum measurement sensitivity for NaCl concentrations is found to be equal to 2.3 dB/(mg/ml) and 7.7°/(mg/ml) for magnitude and phase-shift, respectively. To translate the measurement data (S parameters) to the corresponding complex permittivities, an inversion procedure based on a simple calibration model is applied. The resulting complex permittivities are found to be in a very good agreement with those calculated by Cole-Cole model.

  15. Orientation based segmentation for phase-contrast microscopic image of confluent cell.

    PubMed

    Sasaki, K; Yuasa, T; Sasaki, H; Kato, R

    2013-01-01

    In this research, we propose a novel segmentation method for image of cultured cell at a confluent state, obtained by phase-contrast microscope, based on the orientation. First, we assign to each pixel in the image the direction of an eigenvector corresponding to a smaller eigenvalue of the 2 by 2 Hessian matrix with respect to brightness. Next, we define the orientation at a certain pixel as the histograms of the direction at pixels in the surrounding regions. Then, we evaluate deviation of histograms in the individual regions by entropy, and regard the series of entropy as a multi-dimensional vector, the dimension of which corresponds with the number of regions. We suppose that the vector is assigned to the pixel of interest. Finally, we segment the image based on the multi-dimensional vector using K-means method. We investigate the efficacy of the proposed method using an actual human confluent fibroblast image acquired by phase-contrast microscopy. PMID:24110439

  16. Trace gas monitoring with infrared laser-based detection schemes

    NASA Astrophysics Data System (ADS)

    Sigrist, M. W.; Bartlome, R.; Marinov, D.; Rey, J. M.; Vogler, D. E.; Wächter, H.

    2008-02-01

    The success of laser-based trace gas sensing techniques crucially depends on the availability and performance of tunable laser sources combined with appropriate detection schemes. Besides near-infrared diode lasers, continuously tunable midinfrared quantum cascade lasers and nonlinear optical laser sources are preferentially employed today. Detection schemes are based on sensitive absorption measurements and comprise direct absorption in multi-pass cells as well as photoacoustic and cavity ringdown techniques in various configurations. We illustrate the performance of several systems implemented in our laboratory. These include time-resolved multicomponent traffic emission measurements with a mobile CO2-laser photoacoustic system, a diode-laser based cavity ringdown device for measurements of impurities in industrial process control, isotope ratio measurements with a difference frequency (DFG) laser source combined with balanced path length detection, detection of methylamines for breath analysis with both a near-IR diode laser and a DFG source, and finally, acetone measurements with a heatable multipass cell intended for vapor phase studies on doping agents in urine samples.

  17. A wide field-of-view microscope based on holographic focus grid

    NASA Astrophysics Data System (ADS)

    Wu, Jigang; Cui, Xiquan; Zheng, Guoan; Lee, Lap Man; Yang, Changhuei

    2010-02-01

    We have developed a novel microscope technique that can achieve wide field-of-view (FOV) imaging and yet possess resolution that is comparable to conventional microscope. The principle of wide FOV microscope system breaks the link between resolution and FOV magnitude of traditional microscopes. Furthermore, by eliminating bulky optical elements from its design and utilizing holographic optical elements, the wide FOV microscope system is more cost-effective. In our system, a hologram was made to focus incoming collimated beam into a focus grid. The sample is put in the focal plane and the transmissions of the focuses are detected by an imaging sensor. By scanning the incident angle of the incoming beam, the focus grid will scan across the sample and the time-varying transmission can be detected. We can then reconstruct the transmission image of the sample. The resolution of microscopic image is limited by the size of the focus formed by the hologram. The scanning area of each focus spot is determined by the separation of the focus spots and can be made small for fast imaging speed. We have fabricated a prototype system with a 2.4-mm FOV and 1-μm resolution. The prototype system was used to image onion skin cells for a demonstration. The preliminary experiments prove the feasibility of the wide FOV microscope technique, and the possibility of a wider FOV system with better resolution.

  18. A homemade atomic force microscope based on a quartz tuning fork for undergraduate instruction

    NASA Astrophysics Data System (ADS)

    Li, Yingzi; Zhang, Liwen; Shan, Guanqiao; Song, Zihang; Yang, Rui; Li, Hua; Qian, Jianqiang

    2016-06-01

    Atomic force microscopes are a key tool in nanotechnology that overcome the limitations of optical microscopes and provide imaging capabilities with nanoscale resolution. We have developed an atomic force microscope that uses an inexpensive quartz tuning fork as a micro cantilever. Because of its ease of operation and its open structure, it can be easily customized by students. Due to its low costs, it is possible that every student in the course has access to one setup, allowing all students to obtain deep insights into nanotechnology and to understand the principles of atomic force microscopy.

  19. Space-Based Thermal Infrared Studies of Asteroids

    NASA Astrophysics Data System (ADS)

    Mainzer, A.; Usui, F.; Trilling, D. E.

    Large-area surveys operating at mid-infrared wavelengths have proven to be a valuable means of discovering and characterizing minor planets. Through the use of radiometric models, it is possible to derive physical properties such as diameters, albedos, and thermal inertia for large numbers of objects. Modern detector array technology has resulted in a significant improvement in spatial resolution and sensitivity compared with previous generations of spacebased infrared telescopes, giving rise to a commensurate increase in the number of objects that have been observed at these wavelengths. Spacebased infrared surveys of asteroids therefore offer an effective method of rapidly gathering information about the orbital and physical properties of small-body populations. The AKARI, Wide-field Infrared Survey Explorer (WISE)/ Near- Earth Object Wide-field Infrared Survey Explorer (NEOWISE), Spitzer Space Telescope, and Herschel Space Observatory missions have significantly increased the number of minor planets with well-determined diameters and albedos.

  20. LED-based near infrared sensor for cancer diagnostics

    NASA Astrophysics Data System (ADS)

    Bogomolov, Andrey; Ageev, Vladimir; Zabarylo, Urszula; Usenov, Iskander; Schulte, Franziska; Kirsanov, Dmitry; Belikova, Valeria; Minet, Olaf; Feliksberger, E.; Meshkovsky, I.; Artyushenko, Viacheslav

    2016-03-01

    Optical spectroscopic technologies are increasingly used for cancer diagnostics. Feasibility of differentiation between malignant and healthy samples of human kidney using Fluorescence, Raman, MIR and NIR spectroscopy has been recently reported . In the present work, a simplification of NIR spectroscopy method has been studied. Traditional high-resolution NIR spectrometry was replaced by an optical sensor based on a set of light-emitting diodes at selected wavelengths as light sources and a photodiode. Two prototypes of the sensor have been developed and tested using 14 in-vitro samples of seven kidney tumor patients. Statistical evaluation of results using principal component analysis and partial least-squares discriminant analysis has been performed. Despite only partial discrimination between tumor and healthy tissue achieved by the presented new technique, the results evidence benefits of LED-based near-infrared sensing used for oncological diagnostics. Publisher's Note: This paper, originally published on 4 March, 2016, was replaced with a corrected/revised version on 7 April, 2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance.

  1. High-dynamic range DMD-based infrared scene projector

    NASA Astrophysics Data System (ADS)

    Mansur, David J.; Vaillancourt, Robert; Benedict-Gill, Ryan; Newbry, Scott P.; Rentz Dupuis, Julia

    2013-05-01

    OPTRA is developing a next-generation digital micromirror device (DMD) based two-band infrared scene projector (IRSP) with infinite bit-depth independent of frame rate and an order of magnitude improvement in contrast over the state of the art. Traditionally DMD-based IRSPs have offered larger format and superior uniformity and pixel operability relative to resistive and diode arrays, however, they have been limited in contrast and also by the inherent bitdepth / frame rate tradeoff imposed by pulse width modulation (PWM). OPTRA's high dynamic range IRSP (HIDRA SP) has broken this dependency with a dynamic structured illumination solution. The HIDRA SP uses a source conditioning DMD to impose the structured illumination on two projector DMDs - one for each spectral band. The source conditioning DMD is operated in binary mode, and the relay optics which form the structured illumination act as a low pass spatial filter. The structured illumination is therefore spatially grayscaled and more importantly is analog with no PWM. In addition, the structured illumination concentrates energy where bright object will be projected and extinguishes energy in dark regions; the result is a significant improvement in contrast. The projector DMDs are operated with 8-bit PWM, however the total projected image is analog with no bit-depth / frame rate dependency. In this paper we describe our progress towards the development, build, and test of a prototype HIDRA SP.

  2. Detail enhancement of blurred infrared images based on frequency extrapolation

    NASA Astrophysics Data System (ADS)

    Xu, Fuyuan; Zeng, Deguo; Zhang, Jun; Zheng, Ziyang; Wei, Fei; Wang, Tiedan

    2016-05-01

    A novel algorithm for enhancing the details of the blurred infrared images based on frequency extrapolation has been raised in this paper. Unlike other researchers' work, this algorithm mainly focuses on how to predict the higher frequency information based on the Laplacian pyramid separation of the blurred image. This algorithm uses the first level of the high frequency component of the pyramid of the blurred image to reverse-generate a higher, non-existing frequency component, and adds back to the histogram equalized input blurred image. A simple nonlinear operator is used to analyze the extracted first level high frequency component of the pyramid. Two critical parameters are participated in the calculation known as the clipping parameter C and the scaling parameter S. The detailed analysis of how these two parameters work during the procedure is figure demonstrated in this paper. The blurred image will become clear, and the detail will be enhanced due to the added higher frequency information. This algorithm has the advantages of computational simplicity and great performance, and it can definitely be deployed in the real-time industrial applications. We have done lots of experiments and gave illustrations of the algorithm's performance in this paper to convince its effectiveness.

  3. Visible and infrared image registration based on visual salient features

    NASA Astrophysics Data System (ADS)

    Wu, Feihong; Wang, Bingjian; Yi, Xiang; Li, Min; Hao, Jingya; Qin, Hanlin; Zhou, Huixin

    2015-09-01

    In order to improve the precision of visible and infrared (VIS/IR) image registration, an image registration method based on visual salient (VS) features is presented. First, a VS feature detector based on the modified visual attention model is presented to extract VS points. Because the iterative, within-feature competition method used in visual attention models is time consuming, an alternative fast visual salient (FVS) feature detector is proposed to make VS features more efficient. Then, a descriptor-rearranging (DR) strategy is adopted to describe feature points. This strategy combines information of both IR image and its negative image to overcome the contrast reverse problem between VIS and IR images, making it easier to find the corresponding points on VIS/IR images. Experiments show that both VS and FVS detectors have higher repeatability scores than scale invariant feature transform in the cases of blurring, brightness change, JPEG compression, noise, and viewpoint, except big scale change. The combination of VS detector and DR registration strategy can achieve precise image registration, but it is time-consuming. The combination of FVS detector and DR registration strategy can also reach a good registration of VIS/IR images but in a shorter time.

  4. Real-time panoramic infrared imaging system based on FPGA

    NASA Astrophysics Data System (ADS)

    Zhang, Hao-Jun; Shen, Yong-Ge

    2010-11-01

    During the past decades, signal processing architecture, which is based on FPGA, conventional DSP processor and host computer, is popular for infrared or other electro-optical systems. With the increasing processing requirement, the former architecture starts to show its limitation in several respects. This paper elaborates a solution based on FPGA for panoramic imaging system as our first step of upgrading the processing module to System-on-Chip (SoC) solution. Firstly, we compare this new architecture with the traditional to show its superiority mainly in the video processing ability, reduction in the development workload and miniaturization of the system architecture. Afterwards, this paper provides in-depth description of this imaging system, including the system architecture and its function, and addresses several related issues followed by the future development. FPGA has developed so rapidly during the past years, not only in silicon device but also in the design flow and tools. In the end, we briefly present our future system development and introduce those new design tools to make up the limitation of the traditional FPGA design methodology. The advanced design flow through Simulink and Xilinx System Generator (Sysgen) has been elaborated, which enables engineers to develop sophisticated DSP algorithms and implement them in FPGA more efficiently. It is believed that this new design approach can shorten system design cycle by allowing rapid prototyping and refining design process.

  5. Infrared upconversion as a means of seeing in the dark. [based on nonlinear crystal optics

    NASA Technical Reports Server (NTRS)

    Gurski, T. R.

    1975-01-01

    A new approach to seeing in the dark is described which is based on the principles of nonlinear optics employing a crystal such as lithium iodate. A nonlinear optical device capable of producing photons at higher frequencies from lower-frequency incident light is shown to upconvert infrared light directly into visible light. The major advantages of the infrared upconversion process is that it permits the infrared signal to be detected by photon-counting devices presently available for the visible spectral region, and that it can provide sensitivity to infrared radiation without the need for cryogenic cooling of the detector used. Early works on infrared upconversion are reviewed. The development of applications is discussed as to astronomical spectroscopy and infrared image upconversion involving either angular or positional resolution elements. The demonstration of infrared upconversion in rectangular waveguides of single-crystal GaAs by Anderson et al. (1971) indicates future possibilities in upconversion by the use of integrated optics devices.

  6. Measuring glacier surface temperatures with ground-based thermal infrared imaging

    NASA Astrophysics Data System (ADS)

    Aubry-Wake, Caroline; Baraer, Michel; McKenzie, Jeffrey M.; Mark, Bryan G.; Wigmore, Oliver; Hellström, Robert È.; Lautz, Laura; Somers, Lauren

    2015-10-01

    Spatially distributed surface temperature is an important, yet difficult to observe, variable for physical glacier melt models. We utilize ground-based thermal infrared imagery to obtain spatially distributed surface temperature data for alpine glaciers. The infrared images are used to investigate thermal microscale processes at the glacier surface, such as the effect of surface cover type and the temperature gradient at the glacier margins on the glacier's temperature dynamics. Infrared images were collected at Cuchillacocha Glacier, Cordillera Blanca, Peru, on 23-25 June 2014. The infrared images were corrected based on ground truth points and local meteorological data. For the control points, the Pearson's correlation coefficient between infrared and station temperatures was 0.95. The ground-based infrared camera has the potential for greatly improving glacier energy budget studies, and our research shows that it is critical to properly correct the thermal images to produce robust, quantifiable data.

  7. Microscopic predictions of fission yields based on the time dependent GCM formalism

    NASA Astrophysics Data System (ADS)

    Regnier, D.; Dubray, N.; Schunck, N.; Verrière, M.

    2016-03-01

    Accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r-process to fuel cycle optimization in nuclear energy. The need for a predictive theory applicable where no data is available, together with the variety of potential applications, is an incentive to develop a fully microscopic approach to fission dynamics. One of the most promising theoretical frameworks is the time-dependent generator coordinate method (TDGCM) applied under the Gaussian overlap approximation (GOA). Previous studies reported promising results by numerically solving the TDGCM+GOA equation with a finite difference technique. However, the computational cost of this method makes it difficult to properly control numerical errors. In addition, it prevents one from performing calculations with more than two collective variables. To overcome these limitations, we developed the new code FELIX-1.0 that solves the TDGCM+GOA equation based on the Galerkin finite element method. In this article, we briefly illustrate the capabilities of the solver FELIX-1.0, in particular its validation for n+239Pu low energy induced fission. This work is the result of a collaboration between CEA,DAM,DIF and LLNL on nuclear fission theory.

  8. A smartphone-based chip-scale microscope using ambient illumination

    PubMed Central

    Lee, Seung Ah; Yang, Changhuei

    2014-01-01

    Portable chip-scale microscopy devices can potentially address various imaging needs in mobile healthcare and environmental monitoring. Here, we demonstrate the adaptation of a smartphone’s camera to function as a compact lensless microscope. Unlike other chip-scale microscopy schemes, this method uses ambient illumination as its light source and does not require the incorporation of a dedicated light source. The method is based on the shadow imaging technique where the sample is placed on the surface of the image sensor, which captures direct shadow images under illumination. To improve the imaging resolution beyond the pixel size, we perform pixel super-resolution reconstruction with multiple images at different angles of illumination, which are captured while the user is manually tilting the device around any ambient light source, such as the sun or a lamp. The lensless imaging scheme allows for sub-micron resolution imaging over an ultra-wide field-of-view (FOV). Image acquisition and reconstruction is performed on the device using a custom-built android application, constructing a stand-alone imaging device for field applications. We discuss the construction of the device using a commercial smartphone and demonstrate the imaging capabilities of our system. PMID:24964209

  9. A nitrogen-vacancy spin based molecular structure microscope using multiplexed projection reconstruction

    NASA Astrophysics Data System (ADS)

    Lazariev, Andrii; Balasubramanian, Gopalakrishnan

    2015-09-01

    Methods and techniques to measure and image beyond the state-of-the-art have always been influential in propelling basic science and technology. Because current technologies are venturing into nanoscopic and molecular-scale fabrication, atomic-scale measurement techniques are inevitable. One such emerging sensing method uses the spins associated with nitrogen-vacancy (NV) defects in diamond. The uniqueness of this NV sensor is its atomic size and ability to perform precision sensing under ambient conditions conveniently using light and microwaves (MW). These advantages have unique applications in nanoscale sensing and imaging of magnetic fields from nuclear spins in single biomolecules. During the last few years, several encouraging results have emerged towards the realization of an NV spin-based molecular structure microscope. Here, we present a projection-reconstruction method that retrieves the three-dimensional structure of a single molecule from the nuclear spin noise signatures. We validate this method using numerical simulations and reconstruct the structure of a molecular phantom β-cyclodextrin, revealing the characteristic toroidal shape.

  10. A nitrogen-vacancy spin based molecular structure microscope using multiplexed projection reconstruction

    PubMed Central

    Lazariev, Andrii; Balasubramanian, Gopalakrishnan

    2015-01-01

    Methods and techniques to measure and image beyond the state-of-the-art have always been influential in propelling basic science and technology. Because current technologies are venturing into nanoscopic and molecular-scale fabrication, atomic-scale measurement techniques are inevitable. One such emerging sensing method uses the spins associated with nitrogen-vacancy (NV) defects in diamond. The uniqueness of this NV sensor is its atomic size and ability to perform precision sensing under ambient conditions conveniently using light and microwaves (MW). These advantages have unique applications in nanoscale sensing and imaging of magnetic fields from nuclear spins in single biomolecules. During the last few years, several encouraging results have emerged towards the realization of an NV spin-based molecular structure microscope. Here, we present a projection-reconstruction method that retrieves the three-dimensional structure of a single molecule from the nuclear spin noise signatures. We validate this method using numerical simulations and reconstruct the structure of a molecular phantom β-cyclodextrin, revealing the characteristic toroidal shape. PMID:26370514

  11. A smartphone-based chip-scale microscope using ambient illumination.

    PubMed

    Lee, Seung Ah; Yang, Changhuei

    2014-08-21

    Portable chip-scale microscopy devices can potentially address various imaging needs in mobile healthcare and environmental monitoring. Here, we demonstrate the adaptation of a smartphone's camera to function as a compact lensless microscope. Unlike other chip-scale microscopy schemes, this method uses ambient illumination as its light source and does not require the incorporation of a dedicated light source. The method is based on the shadow imaging technique where the sample is placed on the surface of the image sensor, which captures direct shadow images under illumination. To improve the image resolution beyond the pixel size, we perform pixel super-resolution reconstruction with multiple images at different angles of illumination, which are captured while the user is manually tilting the device around any ambient light source, such as the sun or a lamp. The lensless imaging scheme allows for sub-micron resolution imaging over an ultra-wide field-of-view (FOV). Image acquisition and reconstruction are performed on the device using a custom-built Android application, constructing a stand-alone imaging device for field applications. We discuss the construction of the device using a commercial smartphone and demonstrate the imaging capabilities of our system. PMID:24964209

  12. Detection of blob objects in microscopic zebrafish images based on gradient vector diffusion.

    PubMed

    Li, Gang; Liu, Tianming; Nie, Jingxin; Guo, Lei; Malicki, Jarema; Mara, Andrew; Holley, Scott A; Xia, Weiming; Wong, Stephen T C

    2007-10-01

    The zebrafish has become an important vertebrate animal model for the study of developmental biology, functional genomics, and disease mechanisms. It is also being used for drug discovery. Computerized detection of blob objects has been one of the important tasks in quantitative phenotyping of zebrafish. We present a new automated method that is able to detect blob objects, such as nuclei or cells in microscopic zebrafish images. This method is composed of three key steps. The first step is to produce a diffused gradient vector field by a physical elastic deformable model. In the second step, the flux image is computed on the diffused gradient vector field. The third step performs thresholding and nonmaximum suppression based on the flux image. We report the validation and experimental results of this method using zebrafish image datasets from three independent research labs. Both sensitivity and specificity of this method are over 90%. This method is able to differentiate closely juxtaposed or connected blob objects, with high sensitivity and specificity in different situations. It is characterized by a good, consistent performance in blob object detection. PMID:17654652

  13. Dark-field spectral imaging microscope for localized surface plasmon resonance-based biosensing

    NASA Astrophysics Data System (ADS)

    Yim, Sang-Youp; Park, Jin-Ho; Kim, Min-Gon

    2015-07-01

    Localized surface plasmon resonance (LSPR) of metal nanoparticles makes red-shift of extinction wavelength with an increase in the refractive index at the surface of the metal nanoparticles. Since biomolecules bound to the metal nanoparticle's surface induce refractive index change, biosensing based on LSPR effect can be possible by monitoring scattering or absorption spectrum changes. Generally, however, conventional method detects ensemble averaged LSPR signal of a huge number of metal nanoparticles. Here, we have constructed a dark-field spectral imaging microscope in order to monitor the scattering spectra of individual metal nanoparticles, simultaneously. Gold nanorod (GNR) and aptamer are employed to detect ochratoxin A (OTA) related to a carcinogenic illness. An aptamer-target binding mechanism promotes wavelength shift of extinction spectra due to refractive index change within sensing volume of GNR by structural change of aptamer. A number of GNRs can be identified in a dark-field LSPR image, simultaneously. A typical spectrum of a GNR exhibits red-shift after target binding of molecules and OTA detection is extended to the very low concentration of 1 pM level.

  14. Fabrication of large scale nanostructures based on a modified atomic force microscope nanomechanical machining system.

    PubMed

    Hu, Z J; Yan, Y D; Zhao, X S; Gao, D W; Wei, Y Y; Wang, J H

    2011-12-01

    The atomic force microscope (AFM) tip-based nanomechanical machining has been demonstrated to be a powerful tool for fabricating complex 2D∕3D nanostructures. But the machining scale is very small, which holds back this technique severely. How to enlarge the machining scale is always a major concern for the researches. In the present study, a modified AFM tip-based nanomechanical machining system is established through combination of a high precision X-Y stage with the moving range of 100 mm × 100 mm and a commercial AFM in order to enlarge the machining scale. It is found that the tracing property of the AFM system is feasible for large scale machining by controlling the constant normal load. Effects of the machining parameters including the machining direction and the tip geometry on the uniform machined depth with a large scale are evaluated. Consequently, a new tip trace and an increasing load scheme are presented to achieve a uniform machined depth. Finally, a polymer nanoline array with the dimensions of 1 mm × 0.7 mm, the line density of 1000 lines/mm and the average machined depth of 150 nm, and a 20 × 20 polymer square holes array with the scale of 380 μm × 380 μm and the average machined depth of 250 nm are machined successfully. The uniform of the machined depths for all the nanostructures is acceptable. Therefore, it is verified that the AFM tip-based nanomechanical machining method can be used to machine millimeter scale nanostructures. PMID:22225244

  15. The development of ground-based infrared multi-object spectrograph based on the microshutter array

    NASA Astrophysics Data System (ADS)

    Moon, Dae-Sik; Sivanandam, Suresh; Kutyrev, Alexander S.; Moseley, Samuel H.; Graham, James R.; Roy, Aishwarya

    2014-07-01

    We report on our development of a near-infrared multi-object spectrograph for ground-based applications using the micro-shutter array, which was originally developed for the Near Infrared Spectrograph of the James Webb Space Telescope. The micro-shutter array in this case acts as a source selector at a reimaged telescope focal plane. The developed spectrograph will be implemented either with ground-layer adaptive optics system or multi-conjugate adaptive optics system on a large telescope. This will enable for the first time fully reconfigurable infrared multi-object spectroscopy with adaptive optics systems. We envision studying diverse astronomical objects with our spectrograph, including high-redshift galaxies, galaxy clusters and super star clusters.

  16. Microscopic and infrared spectroscopic comparison of the underwater adhesives produced by germlings of the brown seaweed species Durvillaea antarctica and Hormosira banksii.

    PubMed

    Dimartino, Simone; Savory, David M; Fraser-Miller, Sara J; Gordon, Keith C; McQuillan, A James

    2016-04-01

    Adhesives from marine organisms are often the source of inspiration for the development of glues able to create durable bonds in wet environments. In this work, we investigated the adhesive secretions produced by germlings of two large seaweed species from the South Pacific, Durvillaea antarctica, also named 'the strongest kelp in the word', and its close relative Hormosira banksii The comparative analysis was based on optical and scanning electron microscopy imaging as well as Fourier transform infrared (FTIR) spectroscopy and principal component analysis (PCA). For both species, the egg surface presents peripheral vesicles which are released soon after fertilization to discharge a primary adhesive. This is characterized by peaks representative of carbohydrate molecules. A secondary protein-based adhesive is then secreted in the early developmental stages of the germlings. Energy dispersive X-ray, FTIR and PCA indicate that D. antarctica secretions also contain sulfated moieties, and become cross-linked with time, both conferring strong adhesive and cohesive properties. On the other hand, H. banksii secretions are complemented by the putative adhesive phlorotannins, and are characterized by a simple mechanism in which all constituents are released with the same rate and with no apparent cross-linking. It is also noted that the release of adhesive materials appears to be faster and more copious in D. antarctica than in H. banksii Overall, this study highlights that both quantity and quality of the adhesives matter in explaining the superior attachment ability of D. antarctica. PMID:27122179

  17. [Pre-alarming apparatus for earthquake based on mid-infrared trace methane detection].

    PubMed

    Qiu, He; Liu, Ming-jun; Tian, Xiao-feng

    2014-06-01

    With the rapid development of gas observation technology in seismic fracture zone, in order to accurately predict the earthquake, and reduce the people's lives and property losses caused by earthquake, a mid-infrared methane sensor was designed and developed, which is based on the microscopic relation between methane release and earthquake fissures on the crustal rocks. This instrument utilizes quantum cascaded laser (QCL) operating at 7.65 μm, combined with MIR multipass herriott cell with 76 m absorption path length to obtain low detection sensitivity down to 40 nmol x mol(-1) level in 4s acquisition time. Meanwhile, to decrease the primary noise source (1/f noise), semiconductor laser frequency modulation of direct absorption technology was utilized to obtain gas detection limitation as low as 5 nmol x mol(-1) (40 s acquiring time). In field experiments, controllable vibrator was used as vibration source, a number of trace methane detectors were placed with 100 m distance interval to carry out the dynamic measurement of methane concentration on the ground surface at different distances from the vibration source. Experimental results show that the instrument can monitor the release of underground methane before the earthquake and provide a novel measure as a pre-alarming for earthquake. PMID:25358158

  18. MEMS-based infrared detector for body thermometer

    NASA Astrophysics Data System (ADS)

    Yoo, Kum-Pyo; Kim, Yun-Ho; Min, Nam-Ki

    2005-12-01

    Infrared detectors have many application fields. One of those, MEMS based thermopile is attractive for many low-cost commercial and industrial applications, mainly because it does not require cooling for operation and the process technologies are relatively simple. The MEMS thermopile fabricated on a silicon nitride microbridge structure was proposed. Using microbridge rather conventional membrane makes it possible to fabricate much smaller micro thermopile and to reduce heat loss because of small contact area at silicon rim. The bridge material is only composed of Si3N4. The thermocouple was used a poly-Si and an aluminum. The characteristic of electromotive force (EMF) generation was evaluated for various patterns at hot junction. Aluminum thermocouple shape on bridge structure was designed two patterns. One was a square shape and the other shape was a hollow square. The output voltage of hollow square-type electrode was increased in compared with square-type electrode from 3.03uV/°C to 4.609uV/°C at body temperature (37°C). With the same membrane dimensions and the same overall thickness of the chip a thermopile on microbridge is almost 53% smaller a conventional thermopile chip.

  19. Two-band DMD-based infrared scene simulator

    NASA Astrophysics Data System (ADS)

    Dupuis, Julia Renta; Mansur, David J.; Vaillancourt, Robert; Evans, Thomas; Carlson, David; Schundler, Elizabeth

    2009-05-01

    OPTRA is developing a two-band midwave infrared (MWIR) scene simulator based on digital micromirror device (DMD) technology; this simulator is intended for training various IR threat detection systems that exploit the relative intensities of two separate MWIR spectral bands. Our approach employs two DMDs, one for each spectral band, and an efficient optical design which overlays the scenes reflected by each through a common telecentric projector lens. Other key components include two miniature thermal sources, bandpass filters, and a dichroic beam combiner. Through the use of pulse width modulation, we are able to control the relative intensities of objects simulated by the two channels thereby enabling realistic scene simulations of various targets and projectiles approaching the threat detection system. Performance projections support radiant intensity levels, resolution, bandwidth, and scene durations that meet the requirements for a host of IR threat detection test scenarios. The feasibility of our concept has been demonstrated through the design, build, and test of a breadboard two-band simulator. In this paper we present the design of a prototype two-band simulator which builds on our experience from the breadboard build. We describe the system level, optical, mechanical, and software/electrical designs in detail as well as system characterization and future test plans.

  20. Raman and infrared fingerprint spectroscopy of peroxide-based explosives.

    PubMed

    Oxley, Jimmie; Smith, James; Brady, Joseph; Dubnikova, Faina; Kosloff, Ronnie; Zeiri, Leila; Zeiri, Yehuda

    2008-08-01

    A comparative study of the vibrational spectroscopy of peroxide-based explosives is presented. Triacetone triperoxide (TATP) and hexamethyl-enetriperoxide-diamine (HMTD), now commonly used by terrorists, are examined as well as other peroxide-ring structures: DADP (diacetone diperoxide); TPTP [3,3,6,6,9,9-Hexaethyl-1,2,4,5,7,8-hexaoxo-nonane (tripentanone triperoxide)]; DCypDp {6,7,13,14-Tetraoxadispiro [4.2.4.2]tetradecane (dicyclopentanone diperoxide)}; TCypDp {6,7,15,16,22,23-Hexaoxatrispiro[4.2.4.2.4.2] henicosane (tricyclopentanone triperoxide)}; DCyhDp {7,8,15,16-tetraoxadispiro [5.2.5.2] hexadecane (dicyclohexanone diperoxide)}; and TCyhTp {7,8,14,15,21,22-hexaoxatrispiro [5.2.5.2.5.2] tetracosane (tricyclohexanone triperoxide)}. Both Raman and infrared (IR) spectra were measured and compared to theoretical calculations. The calculated spectra were obtained by calculation of the harmonic frequencies of the studied compounds, at the density functional theory (DFT) B3LYP/cc-pVDZ level of theory, and by the use of scaling factors. It is found that the vibrational features related to the peroxide bonds are strongly mixed. As a result, the spectrum is congested and highly sensitive to minor changes in the molecule. PMID:18702865

  1. Near infrared spectroscopy based brain-computer interface

    NASA Astrophysics Data System (ADS)

    Ranganatha, Sitaram; Hoshi, Yoko; Guan, Cuntai

    2005-04-01

    A brain-computer interface (BCI) provides users with an alternative output channel other than the normal output path of the brain. BCI is being given much attention recently as an alternate mode of communication and control for the disabled, such as patients suffering from Amyotrophic Lateral Sclerosis (ALS) or "locked-in". BCI may also find applications in military, education and entertainment. Most of the existing BCI systems which rely on the brain's electrical activity use scalp EEG signals. The scalp EEG is an inherently noisy and non-linear signal. The signal is detrimentally affected by various artifacts such as the EOG, EMG, ECG and so forth. EEG is cumbersome to use in practice, because of the need for applying conductive gel, and the need for the subject to be immobile. There is an urgent need for a more accessible interface that uses a more direct measure of cognitive function to control an output device. The optical response of Near Infrared Spectroscopy (NIRS) denoting brain activation can be used as an alternative to electrical signals, with the intention of developing a more practical and user-friendly BCI. In this paper, a new method of brain-computer interface (BCI) based on NIRS is proposed. Preliminary results of our experiments towards developing this system are reported.

  2. Infrared face recognition based on binary particle swarm optimization and SVM-wrapper model

    NASA Astrophysics Data System (ADS)

    Xie, Zhihua; Liu, Guodong

    2015-10-01

    Infrared facial imaging, being light- independent, and not vulnerable to facial skin, expressions and posture, can avoid or limit the drawbacks of face recognition in visible light. Robust feature selection and representation is a key issue for infrared face recognition research. This paper proposes a novel infrared face recognition method based on local binary pattern (LBP). LBP can improve the robust of infrared face recognition under different environment situations. How to make full use of the discriminant ability in LBP patterns is an important problem. A search algorithm combination binary particle swarm with SVM is used to find out the best discriminative subset in LBP features. Experimental results show that the proposed method outperforms traditional LBP based infrared face recognition methods. It can significantly improve the recognition performance of infrared face recognition.

  3. Industrial applications of accelerator-based infrared sources: Analysis using infrared microspectroscopy

    SciTech Connect

    Bantignies, J.L.; Fuchs, G.; Wilhelm, C.; Carr, G.L.; Dumas, P.

    1997-09-01

    Infrared Microspectroscopy, using a globar source, is now widely employed in the industrial environment, for the analysis of various materials. Since synchrotron radiation is a much brighter source, an enhancement of an order of magnitude in lateral resolution can be achieved. Thus, the combination of IR microspectroscopy and synchrotron radiation provides a powerful tool enabling sample regions only few microns size to be studied. This opens up the potential for analyzing small particles. Some examples for hair, bitumen and polymer are presented.

  4. Comparison of Diffuse Reflectance Fourier Transform Mid-Infrared and Near-Infrared Spectroscopy with Grating-Based Near-Infrared for the Determination of Fatty Acids in Forages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diffuse reflectance Fourier transform mid-infrared (FTMIR) and near infrared spectroscopy (FTNIR) were compared to scanning monochromator-grating-based near infrared spectroscopy (SMNIR), for their ability to quantify fatty acids (FA) in forages. Thirteen different forage cultivars belonging to 11 d...

  5. (abstract) Infrared Cirrus and Future Space Based Astronomy

    NASA Technical Reports Server (NTRS)

    Gautier, T. N.

    1993-01-01

    A review of the known properties of the distribution of infrared cirrus is followed by a discussion of the implications of cirrus on observations from space. Probable limitations on space observations due to IR cirrus.

  6. ASR potential of quartz based on expansion values and microscopic characteristics of mortar bars

    NASA Astrophysics Data System (ADS)

    Stastna, Aneta; Sachlova, Sarka; Kuchynova, Marketa; Pertold, Zdenek; Prikryl, Richard

    2016-04-01

    The alkali-silica reaction (ASR) is one of the most damaging factors for concrete structures. Different analytical techniques are used to quantify ASR potential of aggregates. The accelerated mortar bar test (ASTM C1260) in combination with the petrographic examination of aggregates by microscopic techniques belongs to the frequently employed methods. Such a methodical approach enables quantification of the ASR potential, based on the expansion values of accelerated mortar bars; and also to identify deleterious components in aggregates. In this study, the accelerated mortar bar test (ASTM C1260) was modified and combined with the scanning electron microscopy of polished sections prepared from mortar bars. The standard 14-day test period of mortar bars was prolonged to 1-year. ASR potential of aggregates was assessed based on expansion values (both 14-day and 1-year) of mortar bars and microscopic analysis of ASR products (alkali silica gels, microcracks, dissolution gaps) detected in the sections. Different varieties of quartz-rich rocks including chert, quartz meta-greywacke, three types of quartzite and pegmatite were used as aggregate. Only quartz from pegmatite was assessed to be non reactive (14-day expansion of 0.08%, 1-year expansion of 1.25%). Aggregate sections exhibited minor ASR products even after 1-year of mortar bar immersion in 1 M NaOH. Expansion values of the rest of samples exceeded the limit of 0.10% after 14-day test period indicating aggregates as reactive. The highest ASR potential was detected in mortar bars containing chert (14-day expansion of 0.55%, 1-year expansion of 2.70%) and quartz meta-greywacke (14-day expansion of 0.46%, 1-year expansion of 2.41%). The high ASR potential was explained by presence of cryptocrystalline matrix in significant volumes (24 - 65 vol%). Influence of the lengths of the immersion in the alkaline solution was observed mainly in the microstructure of the cement paste and on the extension of ASR products. The

  7. High-stability cryogenic scanning tunneling microscope based on a closed-cycle cryostat

    SciTech Connect

    Hackley, Jason D.; Kislitsyn, Dmitry A.; Beaman, Daniel K.; Nazin, George V.; Ulrich, Stefan

    2014-10-15

    We report on the design and operation of a cryogenic ultra-high vacuum (UHV) scanning tunneling microscope (STM) coupled to a closed-cycle cryostat (CCC). The STM is thermally linked to the CCC through helium exchange gas confined inside a volume enclosed by highly flexible rubber bellows. The STM is thus mechanically decoupled from the CCC, which results in a significant reduction of the mechanical noise transferred from the CCC to the STM. Noise analysis of the tunneling current shows current fluctuations up to 4% of the total current, which translates into tip-sample distance variations of up to 1.5 picometers. This noise level is sufficiently low for atomic-resolution imaging of a wide variety of surfaces. To demonstrate this, atomic-resolution images of Au(111) and NaCl(100)/Au(111) surfaces, as well as of carbon nanotubes deposited on Au(111), were obtained. Thermal drift analysis showed that under optimized conditions, the lateral stability of the STM scanner can be as low as 0.18 Å/h. Scanning Tunneling Spectroscopy measurements based on the lock-in technique were also carried out, and showed no detectable presence of noise from the closed-cycle cryostat. Using this cooling approach, temperatures as low as 16 K at the STM scanner have been achieved, with the complete cool-down of the system typically taking up to 12 h. These results demonstrate that the constructed CCC-coupled STM is a highly stable instrument capable of highly detailed spectroscopic investigations of materials and surfaces at the atomic scale.

  8. Individual-based modelling of bacterial cultures to study the microscopic causes of the lag phase.

    PubMed

    Prats, Clara; López, Daniel; Giró, Antoni; Ferrer, Jordi; Valls, Joaquim

    2006-08-21

    The lag phase has been widely studied for years in an effort to contribute to the improvement of food safety. Many analytical models have been built and tested by several authors. The use of Individual-based Modelling (IbM) allows us to probe deeper into the behaviour of individual cells; it is a bridge between theories and experiments when needed. INDividual DIScrete SIMulation (INDISIM) has been developed and coded by our group as an IbM simulator and used to study bacterial growth, including the microscopic causes of the lag phase. First of all, the evolution of cellular masses, specifically the mean mass and biomass distribution, is shown to be a determining factor in the beginning of the exponential phase. Secondly, whenever there is a need for an enzyme synthesis, its rate has a direct effect on the lag duration. The variability of the lag phase with different factors is also studied. The known decrease of the lag phase with an increase in the temperature is also observed in the simulations. An initial study of the relationship between individual and collective lag phases is presented, as a complement to the studies already published. One important result is the variability of the individual lag times and generation times. It has also been found that the mean of the individual lags is greater than the population lag. This is the first in a series of studies of the lag phase that we are carrying out. Therefore, the present work addresses a generic system by making a simple set of assumptions. PMID:16524598

  9. rFRET: A comprehensive, Matlab-based program for analyzing intensity-based ratiometric microscopic FRET experiments.

    PubMed

    Nagy, Peter; Szabó, Ágnes; Váradi, Tímea; Kovács, Tamás; Batta, Gyula; Szöllősi, János

    2016-04-01

    Fluorescence or Förster resonance energy transfer (FRET) remains one of the most widely used methods for assessing protein clustering and conformation. Although it is a method with solid physical foundations, many applications of FRET fall short of providing quantitative results due to inappropriate calibration and controls. This shortcoming is especially valid for microscopy where currently available tools have limited or no capability at all to display parameter distributions or to perform gating. Since users of multiparameter flow cytometry usually apply these tools, the absence of these features in applications developed for microscopic FRET analysis is a significant limitation. Therefore, we developed a graphical user interface-controlled Matlab application for the evaluation of ratiometric, intensity-based microscopic FRET measurements. The program can calculate all the necessary overspill and spectroscopic correction factors and the FRET efficiency and it displays the results on histograms and dot plots. Gating on plots and mask images can be used to limit the calculation to certain parts of the image. It is an important feature of the program that the calculated parameters can be determined by regression methods, maximum likelihood estimation (MLE) and from summed intensities in addition to pixel-by-pixel evaluation. The confidence interval of calculated parameters can be estimated using parameter simulations if the approximate average number of detected photons is known. The program is not only user-friendly, but it provides rich output, it gives the user freedom to choose from different calculation modes and it gives insight into the reliability and distribution of the calculated parameters. © 2016 International Society for Advancement of Cytometry. PMID:27003481

  10. The method of infrared image simulation based on the measured image

    NASA Astrophysics Data System (ADS)

    Lou, Shuli; Liu, Liang; Ren, Jiancun

    2015-10-01

    The development of infrared imaging guidance technology has promoted the research of infrared imaging simulation technology and the key of infrared imaging simulation is the generation of IR image. The generation of IR image is worthful in military and economy. In order to solve the problem of credibility and economy of infrared scene generation, a method of infrared scene generation based on the measured image is proposed. Through researching on optical properties of ship-target and sea background, ship-target images with various gestures are extracted from recorded images based on digital image processing technology. The ship-target image is zoomed in and out to simulate the relative motion between the viewpoint and the target according to field of view and the distance between the target and the sensor. The gray scale of ship-target image is adjusted to simulate the radiation change of the ship-target according to the distance between the viewpoint and the target and the atmospheric transmission. Frames of recorded infrared images without target are interpolated to simulate high frame rate of missile. Processed ship-target images and sea-background infrared images are synthetized to obtain infrared scenes according to different viewpoints. Experiments proved that this method is flexible and applicable, and the fidelity and the reliability of synthesis infrared images can be guaranteed.

  11. Focal plane array based infrared thermography in fine physical experiment

    NASA Astrophysics Data System (ADS)

    Vainer, Boris G.

    2008-03-01

    By two examples of dissimilar physical phenomena causing thermophysical effects, the unique capabilities of one of the up-to-date methods of experimental physics—focal plane array (FPA) based infrared (IR) thermography (IRT), are demonstrated distinctly. Experimenters inexperienced in IRT can grasp how this method provides a means for combining real-time visualization with quantitative analysis. A narrow-band short-wavelength IR camera was used in the experiments. It is discussed and stated that IRT is best matched and suited to the next two test conditions—when a heated specimen is thin and when heat is generated in the immediate region of a surface of a solid. The first prerequisite is realized in the search for directional patterns of combined low-power radiation sources with the use of the IRT-aided method. The second one is realized in studies of water vapour adsorption on uneven (irregular) surfaces of solid materials. With multiple swatches taken from a set of different fabrics and used as experimental samples, a sharp distinction between adsorptivities of their surfaces is strikingly illustrated by IRT time-domain measurements exhibiting the associated thermal effect ranging within an order of magnitude. It is justified that the described IRT-aided test can find practical implementation at least in the light industry. Emissivities of different fabrics are evaluated experimentally with the described reflection method based on the narrow spectral range of IRT. On the basis of direct IR observations, attention is paid to the need for close control over the surface temperature increase while the adsorption isotherms are being measured. Sensitivity of the FPA-based IRT method, as applied to examine the kinetics of initial stages of adsorption of gaseous molecules on the solid surface, is evaluated analytically and quantitatively. The relationship between the amount of adsorbate and the measurable excess of adsorbent temperature is found. It is discovered

  12. Biomimetic infrared sensors based on the infrared receptors of pyrophilous insects

    NASA Astrophysics Data System (ADS)

    Schmitz, Helmut; Kahl, Thilo; Soltner, Helmut; Bousack, Herbert

    2011-04-01

    Beetles of the genus Melanophila and certain flat bugs of the genus Aradus approach forest fires. For the detection of fires and of hot surfaces the pyrophilous species of both genera have developed infrared (IR) receptors, which have developed from common hair mechanoreceptors. Thus this type of insect IR receptor has been termed photomechanic and shows the following two special features: (i) the formation of a complex cuticular sphere consisting of an outer exocuticular shell as well as of a cavernous microfluidic core. (ii) The enclosure of the dendritic tip of a mechanosensitive neuron inside the core in a liquid-filled chamber. Most probably a photomechanic IR sensillum acts as a microfluidic converter of infrared radiation into an increase in internal pressure inside the sphere, which is measured by a mechanosensitive neuron. A simple model for this biological IR sensor is the Golay sensor, which is filled with a liquid instead of gas. Here the absorbed IR radiation results in a pressure increase of the liquid and the deflection of a thin membrane. For the evaluation of this model analytical formulas are presented, which permits the calculation of the pressure increase in the cavity, the deformation of the membrane and the time constant of an artificial leak to compensate ambient temperature changes. Some organic liquids with high thermal expansion coefficients may improve the deflection of the membrane compared to water.

  13. Research and experiment of InGaAs shortwave infrared imaging system based on FPGA

    NASA Astrophysics Data System (ADS)

    Ren, Ling; Min, Chaobo; Sun, Jianning; Gu, Yan; Yang, Feng; Zhu, Bo; Pan, Jingsheng; Guo, Yiliang

    2015-04-01

    The design and imaging characteristic experiment of InGaAs shortwave infrared imaging system are introduced. Through the adoption of InGaAs focal plane array, the real time image process structure of InGaAs shortwave infrared imaging system is researched. The hardware circuit and image process software of the imaging system based on FPGA are researched. The InGaAs shortwave infrared imaging system is composed of shortwave infrared lens, InGaAs focal plane array, temperature controller module, power supply module, analog-to-digital converter module, digital-to-analog converter module, FPGA image processing module and optical-mechanical structure. The main lock frequency of InGaAs shortwave infrared imaging system is 30MHz. The output mode of the InGaAs shortwave infrared imaging system is PAL analog signal. The power dissipation of the imaging system is 2.6W. The real time signal process in InGaAs shortwave infrared imaging system includes non-uniformly correction algorithm, bad pixel replacement algorithm, and histogram equalization algorithm. Based on the InGaAs shortwave infrared imaging system, the imaging characteristic test of shortwave infrared is carried out for different targets in different conditions. In the foggy weather, the haze and fog penetration are tested. The InGaAs shortwave infrared imaging system could be used for observing humans, boats, architecture, and mountains in the haze and foggy weather. The configuration and performance of InGaAs shortwave infrared imaging system are respectively logical and steady. The research on the InGaAs shortwave infrared imaging system is worthwhile for improving the development of night vision technology.

  14. Multiple pinhole collimator based microscopic x-ray luminescence computed tomography

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Zhu, Dianwen; Li, Changqing

    2016-03-01

    X-ray luminescence computed tomography (XLCT) is a new hybrid imaging modality, which has the capability to improve optical spatial resolution to hundreds of micrometers for deep targets. In this paper, we report a multiple pinhole collimator based microscopic X-ray luminescence computed tomography (microXLCT) system for small animal imaging. Superfine collimated X-ray pencil beams are used to excite deeply embedded phosphor particles, allowing us to obtain sub-millimeter optical spatial resolution in deep tissues. Multiple collimated X-ray beams are generated by mounting an array of pinholes in the front of a powerful X-ray tube. With multiple X-ray beams scanning, the phosphor particles in the region of the multiple beams are excited simultaneously, which requires less scanning time compared with a single beam scanning. The emitted optical photons on the top surface of the phantom are measured with an electron multiplying charge-coupled device (EMCCD) camera. Meanwhile, an X-ray detector is used to determine the X-ray beam size and position, which are used as structural guidance in the microXLCT image reconstruction. To validate the performance of our proposed multiple pinhole based microXLCT imaging system, we have performed numerical simulations and a phantom experiment. In the numerical simulations, we simulated a cylindrical phantom with two and six embedded targets, respectively. In the simulations, we used four parallel X-ray beams with the beam diameter of 0.1 mm and the beam interval of 3.2 mm. We can reconstruct deeply embedded multiple targets with a target diameter of 0.2 mm using measurements in six projections, which indicated that four parallel X-ray beam scan could reduce scanning time without comprising the reconstructed image quality. In the phantom experiment, we generated two parallel X-ray beams with the beam diameter of 0.5 mm and the beam interval of 4.2 mm. We scanned a phantom of one target with the two parallel X-ray beams. The target was

  15. The maxillary molar endodontic access opening: A microscope-based approach

    PubMed Central

    Mamoun, John Sami

    2016-01-01

    This article reviews the basic clinical techniques of performing a maxillary molar endodontic access opening, starting from the initial access opening into the pulp chamber, to the point where a size #10 file has been advanced to the apices of all three or four (or more) canals. The article explains how the use of the dental surgical operating microscope or microscope-level loupes magnification of ×6–8 or greater, combined with head-mounted or coaxial illumination, improve the ability of a dentist to identify microscopic root canal orifices, which facilitates the efficient creation of conservative access openings with adequate straight-line access in maxillary molars. Magnified photos illustrate various microscopic anatomical structures or landmarks of the initial access opening. Techniques are explored for implementing an access opening for teeth with vital versus necrotic pulpal tissues. The article also explores the use of piezoelectric or ultrasonic instruments for revealing root canal orifices and for removing pulp stones or calcified pulpal tissue inside the pulp chamber. PMID:27403069

  16. Construction of a microscopic agent-based model for firms' dynamics

    NASA Astrophysics Data System (ADS)

    Iyetomi, Hiroshi; Aoyama, Hideaki; Fujiwara, Yoshi; Ikeda, Yuichi; Kaizoji, Taisei; Soma, Wataru

    2005-07-01

    A workable microscopic model for firms' dynamics has been constructed. The model consists of firm agents and a bank agent dynamics of which are described by balance sheets. The size distribution of firms and the temporal evolution of the bank show critical dependence on whether or not firms use perfect information on their financial conditions to draw up next production plans.

  17. The maxillary molar endodontic access opening: A microscope-based approach.

    PubMed

    Mamoun, John Sami

    2016-01-01

    This article reviews the basic clinical techniques of performing a maxillary molar endodontic access opening, starting from the initial access opening into the pulp chamber, to the point where a size #10 file has been advanced to the apices of all three or four (or more) canals. The article explains how the use of the dental surgical operating microscope or microscope-level loupes magnification of ×6-8 or greater, combined with head-mounted or coaxial illumination, improve the ability of a dentist to identify microscopic root canal orifices, which facilitates the efficient creation of conservative access openings with adequate straight-line access in maxillary molars. Magnified photos illustrate various microscopic anatomical structures or landmarks of the initial access opening. Techniques are explored for implementing an access opening for teeth with vital versus necrotic pulpal tissues. The article also explores the use of piezoelectric or ultrasonic instruments for revealing root canal orifices and for removing pulp stones or calcified pulpal tissue inside the pulp chamber. PMID:27403069

  18. Thermal Infrared Imaging-Based Computational Psychophysiology for Psychometrics.

    PubMed

    Cardone, Daniela; Pinti, Paola; Merla, Arcangelo

    2015-01-01

    Thermal infrared imaging has been proposed as a potential system for the computational assessment of human autonomic nervous activity and psychophysiological states in a contactless and noninvasive way. Through bioheat modeling of facial thermal imagery, several vital signs can be extracted, including localized blood perfusion, cardiac pulse, breath rate, and sudomotor response, since all these parameters impact the cutaneous temperature. The obtained physiological information could then be used to draw inferences about a variety of psychophysiological or affective states, as proved by the increasing number of psychophysiological studies using thermal infrared imaging. This paper presents therefore a review of the principal achievements of thermal infrared imaging in computational physiology with regard to its capability of monitoring psychophysiological activity. PMID:26339284

  19. Thermal Infrared Imaging-Based Computational Psychophysiology for Psychometrics

    PubMed Central

    Cardone, Daniela; Pinti, Paola; Merla, Arcangelo

    2015-01-01

    Thermal infrared imaging has been proposed as a potential system for the computational assessment of human autonomic nervous activity and psychophysiological states in a contactless and noninvasive way. Through bioheat modeling of facial thermal imagery, several vital signs can be extracted, including localized blood perfusion, cardiac pulse, breath rate, and sudomotor response, since all these parameters impact the cutaneous temperature. The obtained physiological information could then be used to draw inferences about a variety of psychophysiological or affective states, as proved by the increasing number of psychophysiological studies using thermal infrared imaging. This paper presents therefore a review of the principal achievements of thermal infrared imaging in computational physiology with regard to its capability of monitoring psychophysiological activity. PMID:26339284

  20. Synchrotron-based far-infrared spectroscopy of nickel tungstate

    NASA Astrophysics Data System (ADS)

    Kalinko, A.; Kuzmin, A.; Roy, P.; Evarestov, R. A.

    2016-07-01

    Monoclinic antiferromagnetic NiWO4 was studied by far-infrared (30-600 cm-1) absorption spectroscopy in the temperature range of 5-300 K using the synchrotron radiation from SOLEIL source. Two isomorphous CoWO4 and ZnWO4 tungstates were investigated for comparison. The phonon contributions in the far-infrared range of tungstates were interpreted using the first-principles spin-polarized linear combination of atomic orbital calculations. No contributions from magnetic excitations were found in NiWO4 and CoWO4 below their Neel temperatures down to 5 K.

  1. Recurrence tracking microscope

    SciTech Connect

    Saif, Farhan

    2006-03-15

    In order to probe nanostructures on a surface we present a microscope based on the quantum recurrence phenomena. A cloud of atoms bounces off an atomic mirror connected to a cantilever and exhibits quantum recurrences. The times at which the recurrences occur depend on the initial height of the bouncing atoms above the atomic mirror, and vary following the structures on the surface under investigation. The microscope has inherent advantages over existing techniques of scanning tunneling microscope and atomic force microscope. Presently available experimental technology makes it possible to develop the device in the laboratory.

  2. Homogeneity and internal defects detect of infrared Se-based chalcogenide glass

    NASA Astrophysics Data System (ADS)

    Li, Zupana; Wu, Ligang; Lin, Changgui; Song, Bao'an; Wang, Xunsi; Shen, Xiang; Dai, Shixunb

    2011-10-01

    Ge-Sb-Se chalcogenide glasses is a kind of excellent infrared optical material, which has been enviromental friendly and widely used in infrared thermal imaging systems. However, due to the opaque feature of Se-based glasses in visible spectral region, it's difficult to measure their homogeneity and internal defect as the common oxide ones. In this study, a measurement was proposed to observe the homogeneity and internal defect of these glasses based on near-IR imaging technique and an effective measurement system was also constructed. The testing result indicated the method can gives the information of homogeneity and internal defect of infrared Se-based chalcogenide glass clearly and intuitionally.

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  4. IR Cards: Inquiry-Based Introduction to Infrared Spectroscopy

    ERIC Educational Resources Information Center

    Bennett, Jacqueline; Forster, Tabetha

    2010-01-01

    As infrared spectroscopy (IR) is frequently used in undergraduate organic chemistry courses, an inductive introduction to IR spectroscopy that uses index cards printed with spectra, structures, and chemical names is described. Groups of students are given an alphabetized deck of these "IR cards" to sort into functional groups. The students then…

  5. Distributed microscopy: toward a 3D computer-graphic-based multiuser microscopic manipulation, imaging, and measurement system

    NASA Astrophysics Data System (ADS)

    Sulzmann, Armin; Carlier, Jerome; Jacot, Jacques

    1996-10-01

    The aim of this project is to telecontrol the movements in 3D-space of a microscope in order to manipulate and measure microsystems or micro parts aided by multi-user virtual reality (VR) environments. Presently microsystems are gaining in interest. Microsystems are small, independent modules, incorporating various functions, such as electronic, micro mechanical, data processing, optical, chemical, medical and biological functions. Though improving the manufacturing technologies, the measurement of the small structures to insure the quality of the process is a key information for the development. So far to measure the micro structures strong microscopes are needed. The use of highly magnifying computerized microscopes is expensive. To insure high quality measurements and distribute the acquired information to multi-user our proposed system is divided into three parts: the virtual reality microscopic environment (VRME)-based user-interface on a SGI workstation to prepare the manipulations and measurements. Secondly the computerized light microscope with the vision system inspecting the scene and getting the images of the specimen. Newly developed vision algorithms are used to analyze micro structures in the scene corresponding to the known a priori model. This vision is extracting position and shape of the objects and then transmitted as feedback to the user of the VRME-system to update his virtual environment. The internet demon is the third part of the system and distributes the information about the position of the micro structures, their shape and the images to the connected users who themselves may interact with the microscope (turn and displace the specimen on the back of a moving platform, or adding their structures to the scene and compare). The key idea behind our project VRME is to use the intuitiveness and the 3D visualization of VR environments coupled with a vision system to perform measurements of micro structures at a high accuracy. The direct

  6. Fluorescence microscopy imaging with a Fresnel zone plate array based optofluidic microscope

    PubMed Central

    Han, Chao; Lee, Lap Man; Yang, Changhuei

    2013-01-01

    We report the implementation of an on-chip microscope system, termed fluorescence optofluidic microscope (FOFM), which is capable of fluorescence microscopy imaging of samples in fluid media. The FOFM employs an array of Fresnel zone plates (FZP) to generate an array of focused light spots within a microfluidic channel. As a sample flows through the channel and across the array of focused light spots, the fluorescence emissions are collected by a filter-coated CMOS sensor, which serves as the channel's floor. The collected data can then be processed to render fluorescence microscopy images at a resolution determined by the focused light spot size (experimentally measured as 0.65 μm FWHM). In our experiments, our established resolution was 1.0 μm due to Nyquist criterion consideration. As a demonstration, we show that such a system can be used to image the cell nuclei stained by Acridine Orange and cytoplasm labeled by Qtracker®. PMID:21935556

  7. Porphyrin Based Near Infrared-Absorbing Materials for Organic Photovoltaics

    NASA Astrophysics Data System (ADS)

    Zhong, Qiwen

    The conservation and transformation of energy is essential to the survival of mankind, and thus concerns every modern society. Solar energy, as an everlasting source of energy, holds one of the key solutions to some of the most urgent problems the world now faces, such as global warming and the oil crisis. Advances in technologies utilizing clean, abundant solar energy, could be the steering wheel of our societies. Solar cells, one of the major advances in converting solar energy into electricity, are now capturing people's interest all over the globe. While solar cells have been commercially available for many years, the manufacturing of solar cells is quite expensive, limiting their broad based implementation. The cost of solar cell based electricity is 15-50 cents per kilowatt hour (¢/kwh), depending on the type of solar cell, compared to 0.7 ¢/kwh for fossil fuel based electricity. Clearly, decreasing the cost of electricity from solar cells is critical for their wide spread deployment. This will require a decrease in the cost of light absorbing materials and material processing used in fabricating the cells. Organic photovoltaics (OPVs) utilize organic materials such as polymers and small molecules. These devices have the advantage of being flexible and lower cost than conventional solar cells built from inorganic semiconductors (e.g. silicon). The low cost of OPVs is tied to lower materials and fabrication costs of organic cells. However, the current power conversion efficiencies of OPVs are still below 15%, while convention crystalline Si cells have efficiencies of 20-25%. A key limitation in OPVs today is their inability to utilize the near infrared (NIR) portion of the solar spectrum. This part of the spectrum comprises nearly half of the energy in sunlight that could be used to make electricity. The first and foremost step in conversion solar energy conversion is the absorption of light, which nature has provided us optimal model of, which is

  8. M3: Microscope-based maskless micropatterning with dry film photoresist

    PubMed Central

    Leigh, Steven Y.; Tattu, Aashay; Mitchell, Joseph S. B.

    2011-01-01

    We present a maskless micropatterning system that utilizes a fluorescence microscope with programmable X-Y stage and dry film photoresist to realize feature sizes in the sub-millimeter range (40–700 μm). The method allows for flexible in-house maskless photolithography without a dedicated microfabrication facility and is well-suited for rapid prototyping of microfluidic channels, scaffold templates for protein/cell patterning or optically-guided cell encapsulation for biomedical applications. PMID:21190086

  9. The plant virus microscope image registration method based on mismatches removing.

    PubMed

    Wei, Lifang; Zhou, Shucheng; Dong, Heng; Mao, Qianzhuo; Lin, Jiaxiang; Chen, Riqing

    2016-01-01

    The electron microscopy is one of the major means to observe the virus. The view of virus microscope images is limited by making specimen and the size of the camera's view field. To solve this problem, the virus sample is produced into multi-slice for information fusion and image registration techniques are applied to obtain large field and whole sections. Image registration techniques have been developed in the past decades for increasing the camera's field of view. Nevertheless, these approaches typically work in batch mode and rely on motorized microscopes. Alternatively, the methods are conceived just to provide visually pleasant registration for high overlap ratio image sequence. This work presents a method for virus microscope image registration acquired with detailed visual information and subpixel accuracy, even when overlap ratio of image sequence is 10% or less. The method proposed focus on the correspondence set and interimage transformation. A mismatch removal strategy is proposed by the spatial consistency and the components of keypoint to enrich the correspondence set. And the translation model parameter as well as tonal inhomogeneities is corrected by the hierarchical estimation and model select. In the experiments performed, we tested different registration approaches and virus images, confirming that the translation model is not always stationary, despite the fact that the images of the sample come from the same sequence. The mismatch removal strategy makes building registration of virus microscope images at subpixel accuracy easier and optional parameters for building registration according to the hierarchical estimation and model select strategies make the proposed method high precision and reliable for low overlap ratio image sequence. PMID:26519816

  10. The Narrow Band AOTF Based Hyperspectral Microscopic Imaging on the Rat Skin Stratum Configuration

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Wang, H.; Huang, J.; Gao, Q.

    2014-08-01

    A noncollinear acousto-optic tunable filter (AOTF) was designed with a comprehensive treatment of the properties of TeO2 as an acoustooptic (A-O) material. The results of optical testing validated that it predicted the performance of the designed AOTF. The bandwidth of the AOTF was very narrow in the visible light range. The high spectral resolution of AOTF was useful in practical applications to the hyperspectral imaging. The experimentally observed spectral pattern of the diffracted light was nearly the same as the theoretical result. The measured tuning relationship between the diffracted central optical wavelength and acoustic frequency was in accordance with the theoretical prediction. It demonstrates the accuracy of our design theory. Furthermore, by selecting the AOTF as the spectroscopic element, a hyperspectral microscopic imaging system was designed. The hyperspectral microscopic images of the rat skin tissue under the different optical center wavelength were acquired. The experimental results indicated that the imaging performance was satisfactory. The stratums of the rat skin can be clearly distinguished. The inner details of the epidermis and the corium can be shown on the hyperspectral microscopic images. Some differences also can be found by the comparison of the hyperspectal images under the different optical wavelengths. The study indicated the applicability and the advantage of our system on biomedicine area.

  11. Infrared face recognition based on LBP histogram and KW feature selection

    NASA Astrophysics Data System (ADS)

    Xie, Zhihua

    2014-07-01

    The conventional LBP-based feature as represented by the local binary pattern (LBP) histogram still has room for performance improvements. This paper focuses on the dimension reduction of LBP micro-patterns and proposes an improved infrared face recognition method based on LBP histogram representation. To extract the local robust features in infrared face images, LBP is chosen to get the composition of micro-patterns of sub-blocks. Based on statistical test theory, Kruskal-Wallis (KW) feature selection method is proposed to get the LBP patterns which are suitable for infrared face recognition. The experimental results show combination of LBP and KW features selection improves the performance of infrared face recognition, the proposed method outperforms the traditional methods based on LBP histogram, discrete cosine transform(DCT) or principal component analysis(PCA).

  12. Design of an infrared camera based aircraft detection system for laser guide star installations

    SciTech Connect

    Friedman, H.; Macintosh, B.

    1996-03-05

    There have been incidents in which the irradiance resulting from laser guide stars have temporarily blinded pilots or passengers of aircraft. An aircraft detection system based on passive near infrared cameras (instead of active radar) is described in this report.

  13. Infrared dim target detection technology based on background estimate

    NASA Astrophysics Data System (ADS)

    Lei, Liu; Zhijian, Huang

    2014-01-01

    Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, two new algorithms - background estimate and frame difference fusion method, and building background with neighborhood mean method are presented. The basic principles and the implementing procedure of these algorithms for target detection are described. Using these algorithms, the experiments on some real-life IR images are performed. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective view and objective view. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

  14. Infrared-thermography-based pipeline leak detection systems

    NASA Astrophysics Data System (ADS)

    Weil, Gary J.; Graf, Richard J.

    1991-03-01

    Computerized Infrared Thermographic pipeline inspection is now a refined and accurate process having been thoroughly proven to be an accurate, cost effective, and efficient technology during a 10 year development and testing process. The process has been used to test pipelines in chemical plants, water supply systems, steam lines, natural gas pipelines and sewer systems. Its non-contact, nondestructive ability to inspect large areas from above ground with 100% coverage and to locate subsurface leaks as well as the additional capability to locate voids and erosion surrounding pipelines make its testing capabilities unique. This paper will detail the development of computerized infrared thermographic pipeline testing along with case histories illustrating its implementation problems and successes and innovations anticipated for the future.

  15. Underground fluid composition analysis based on the near infrared spectrum

    NASA Astrophysics Data System (ADS)

    Li, Wenxi; Liao, Yanbiao; Zhang, Min

    2011-11-01

    The near-infrared spectrum is very practical for real-time analyzing in the field of industry. This paper describes the structure of optical system, which is a part of the well logging instruments. The optical system is designed to analyze the composition of underground fluid, using the differences between oil and water in near-infrared absorption. Using Beer- Lambert law, the article analyzes the light intensity when broad-spectrum light passes through the liquid. According to the results of analysis, a group of wavelength including center wavelength and bandwidth can be selected. With each selected wavelength, light intensity changes significantly as the concentration of liquid changes. By measuring the light intensity, the system can analyse the composition of underground fluid.

  16. AOTF-based near-infrared imaging spectrometer for rapid identification of camouflaged target

    NASA Astrophysics Data System (ADS)

    Gao, Zhifan; Zeng, Libo; Wu, Qiongshui

    2014-11-01

    Acousto-optic tunable filter (AOTF) is a novel device for spectrometer. The electronic tunability qualifies it with the most compelling advantages of higher wavelength scan rate over the conventional spectrometers that are mechanically tuned, and the feature of large angular aperture makes the AOTF particularly suitable in imaging applications. In this research, an AOTF-based near-infrared imaging spectrometer was developed. The spectrometer consists of a TeO2 AOTF module, a near-infrared imaging lens assembly, an AOTF controller, an InGaAs array detector, an image acquisition card, and a PC. A precisely designed optical wedge is placed at the emergent surface of the AOTF to deal with the inherent dispersion of the TeO2 that may degrade the spatial resolution. The direct digital synthesizer (DDS) techniques and the phase locked loop (PLL) techniques are combined for radio frequency (RF) signal synthesis. The PLL is driven by the DDS to take advantage of both their merits of high frequency resolution, high frequency scan rate and strong spurious signals resistance capability. All the functions relating to wavelength scan, image acquisition, processing, storge and display are controlled by the PC. Calibration results indicate that the spectral range is 898~1670 nm, the spectral resolution is 6.8 nm(@1064 nm), the wavelength separation between frames in the spectral image assembly is 1.0 nm, and the processing time of a single image is less than 1 ms if a TV camera with 640×512 detector is incorporated. A prototype device was assembled to test the capability of differentiating samples with similar appearances, and satisfactory results were achieved. By this device, the chemical compositions and the distribution information can be obtained simultaneously. This system has the most advantages of no moving parts, fast wavelength scan and strong vibration resistance. The proposed imaging spectrometer has a significant application prospect in the area of identification of

  17. Infrared small target detection technology based on OpenCV

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Huang, Zhijian

    2013-09-01

    Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

  18. Infrared small target detection technology based on OpenCV

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Huang, Zhijian

    2013-05-01

    Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

  19. Label-free imaging of arterial tissues using photonic crystal fiber (PCF) based nonlinear optical microscopic system

    NASA Astrophysics Data System (ADS)

    Ko, Alex C. T.; Ridsdale, Andrew; Pegoraro, Adrian F.; Smith, Michael S. D.; Mostaço-Guidolin, Leila B.; Hewko, Mark D.; Kohlenberg, Elicia M.; Schattka, Bernie J.; Shiomi, Masashi; Stolow, Albert; Sowa, Michael G.

    2009-02-01

    Nonlinear optical (NLO) microscopy provides a minimally invasive optical method for fast molecular imaging at subcellular resolution with 3D sectioning capability in thick, highly scattering biological tissues. In the current study, we demonstrate the imaging of arterial tissue using a nonlinear optical microscope based on photonic crystal fiber and a single femto-second oscillator operating at 800nm. This NLO microscope system is capable of simultaneous imaging extracellular elastin/collagen structures and lipid distribution within aortic tissue obtained from coronary atherosclerosis-prone WHHLMI rabbits (Watanabe heritable hyperlipidemic rabbit-myocardial infarction) Clear pathological differences in arterial lumen surface were observed between healthy arterial tissue and atherosclerotic lesions through NLO imaging.

  20. On the conversion of infrared radiation from fission reactor-based photon engine into parallel beam

    NASA Astrophysics Data System (ADS)

    Gulevich, Andrey V.; Levchenko, Vladislav E.; Loginov, Nicolay I.; Kukharchuk, Oleg F.; Evtodiev, Denis A.; Zrodnikov, Anatoly V.

    2002-01-01

    The efficiency of infrared radiation conversion from photon engine based on fission reactor into parallel photon beam is discussed. Two different ways of doing that are considered. One of them is to use the parabolic mirror to convert of infrared radiation into parallel photon beam. The another one is based on the use of special lattice consisting of numerous light conductors. The experimental facility and some results are described. .

  1. Microscopic Polyangiitis

    MedlinePlus

    ... include purplish bumps and spots pictured below (palpable purpura). These areas range in size from several millimeters ... Syndrome (EGPA) Cryoglobulinemia Giant Cell Arteritis Henoch-Schönlein Purpura Microscopic Polyangiitis Polyarteritis Nodosa Rheumatoid Vasculitis Takayasu’s Arteritis ...

  2. Quantitative Characterization of Super-Resolution Infrared Imaging Based on Time-Varying Focal Plane Coding

    NASA Astrophysics Data System (ADS)

    Wang, X.; Yuan, Y.; Zhang, J.; Chen, Y.; Cheng, Y.

    2014-10-01

    High resolution infrared image has been the goal of an infrared imaging system. In this paper, a super-resolution infrared imaging method using time-varying coded mask is proposed based on focal plane coding and compressed sensing theory. The basic idea of this method is to set a coded mask on the focal plane of the optical system, and the same scene could be sampled many times repeatedly by using time-varying control coding strategy, the super-resolution image is further reconstructed by sparse optimization algorithm. The results of simulation are quantitatively evaluated by introducing the Peak Signal-to-Noise Ratio (PSNR) and Modulation Transfer Function (MTF), which illustrate that the effect of compressed measurement coefficient r and coded mask resolution m on the reconstructed image quality. Research results show that the proposed method will promote infrared imaging quality effectively, which will be helpful for the practical design of new type of high resolution ! infrared imaging systems.

  3. Infrared image superframing technique based on high-speed digital transmission circuit

    NASA Astrophysics Data System (ADS)

    Hong, Wenqing; Yao, Libin; Ji, Rongbin; Liu, Chuanming

    2013-09-01

    With the sustaining development of application requirements in infrared technology, modern infrared imaging system demands high frame rates, wide dynamic range, high spatial resolution and high sensitivity. Because it is impossible to integrate hundreds of pF capacitor in the limited area of detector pixel, the integration time of infrared staring imaging system will be restricted. Therefore, the underutilization of detector performance is unavoidable. Specially, long wave infrared detector must accommodate stronger infrared signal, and the integration capacitor is more easily saturated. For the sake of resolving the restriction of integration capacitor, an infrared image superframing technique based on high-speed digital transmission circuit is presented in this paper. Meanwhile, the mass raw data high-speed transmission from detector to imaging circuit is also capable via the proposed technique. With the usage of the technique, the signal to noise ratio (SNR) of infrared imaging system will be improved, and the dynamic range of infrared imaging system will be also extended. The theory analysis and results of simulation demonstrate that the proposed method is feasible and effective.

  4. Optical-disk-based imaging system to be used as an optical microscope

    NASA Astrophysics Data System (ADS)

    Shima, Takayuki; Fujimaki, Makoto; Awazu, Koichi

    2016-07-01

    An optical disk surface is scanned spirally by laser light, as in the case of digital versatile discs, and a reflectance image is formed by rearranging the scanned intensity results. A prototype system is developed for imaging with a rotary encoder equipped to precisely control the disk rotation angle. We measured Escherichia coli dispersed on an optical disk sample surface and successfully obtained an image that is identical to that obtained using an optical microscope. The system is advantageous as an optical sensor for detecting sub-micrometer- to micrometer-order substances on a large-area surface.

  5. [Microscopic colitis: update 2014].

    PubMed

    Burgmann, Konstantin; Fraga, Montserrat; Schoepfer, Alain M; Yun, Pu

    2014-09-01

    Microscopic colitis, which includes lymphocytic colitis and collagenous colitis, represents a frequent cause of chronic watery diarrhea especially in the elderly population. Several medications, such as nonsteroidal antiinflammatory drugs, proton pump inhibitors or antidepressants, as well as cigarette smoking have been recognized as risk factors for microscopic colitis. The diagnosis of microscopic colitis is based on a macroscopically normal ileo-colonoscopy and several biopsies from the entire colon, which demonstrate the pathognomonic histopathologic findings. Therapy is mainly based on the use of budesonide. Other medications, such as mesalazine, cholestyramine and bismuth, have been evaluated as well but the evidence is less solid. PMID:25276996

  6. Measuring microscopic evolution processes of complex networks based on empirical data

    NASA Astrophysics Data System (ADS)

    Chi, Liping

    2015-04-01

    Aiming at understanding the microscopic mechanism of complex systems in real world, we perform the measurement that characterizes the evolution properties on two empirical data sets. In the Autonomous Systems Internet data, the network size keeps growing although the system suffers a high rate of node deletion (r = 0.4) and link deletion (q = 0.81). However, the average degree keeps almost unchanged during the whole time range. At each time step the external links attached to a new node are about c = 1.1 and the internal links added between existing nodes are approximately m = 8. For the Scientific Collaboration data, it is a cumulated result of all the authors from 1893 up to the considered year. There is no deletion of nodes and links, r = q = 0. The external and internal links at each time step are c = 1.04 and m = 0, correspondingly. The exponents of degree distribution p(k) ∼ k-γ of these two empirical datasets γdata are in good agreement with that obtained theoretically γtheory. The results indicate that these evolution quantities may provide an insight into capturing the microscopic dynamical processes that govern the network topology.

  7. A near-field scanning microwave microscope based on a superconducting resonator for low power measurements.

    PubMed

    de Graaf, S E; Danilov, A V; Adamyan, A; Kubatkin, S E

    2013-02-01

    We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 μV, approaching low enough photon population (N ∼ 1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6.4 × 10(-20) F/Hz, limited by mechanical noise. We believe that the results presented here are a significant step towards probing quantum systems at the nanoscale using near-field scanning microwave microscopy. PMID:23464217

  8. Microscopic Gold Particle-Based Fiducial Markers for Proton Therapy of Prostate Cancer

    SciTech Connect

    Lim, Young Kyung; Kwak, Jungwon; Kim, Dong Wook; Shin, Dongho; Yoon, Myonggeun; Park, Soah; Kim, Jin Sung; Ahn, Sung Hwan; Shin, Jungwook; Lee, Se Byeong Park, Sung Yong; Pyo, Hong Ryeol; Kim, Dae Yong M.D.; Cho, Kwan Ho

    2009-08-01

    Purpose: We examined the feasibility of using fiducial markers composed of microscopic gold particles and human-compatible polymers as a means to overcome current problems with conventional macroscopic gold fiducial markers, such as dose reduction and artifact generation, in proton therapy for prostate cancer. Methods and Materials: We examined two types of gold particle fiducial marker interactions: that with diagnostic X-rays and with a therapeutic proton beam. That is, we qualitatively and quantitatively compared the radiographic visibility of conventional gold and gold particle fiducial markers and the CT artifacts and dose reduction associated with their use. Results: The gold particle fiducials could be easily distinguished from high-density structures, such as the pelvic bone, in diagnostic X-rays but were nearly transparent to a proton beam. The proton dose distribution was distorted <5% by the gold particle fiducials with a 4.9% normalized gold density; this was the case even in the worst configuration (i.e., parallel alignment with a single-direction proton beam). In addition, CT artifacts were dramatically reduced for the gold particle mixture. Conclusion: Mixtures of microscopic gold particles and human-compatible polymers have excellent potential as fiducial markers for proton therapy for prostate cancer. These include good radiographic visibility, low distortion of the depth-dose distribution, and few CT artifacts.

  9. A near-field scanning microwave microscope based on a superconducting resonator for low power measurements

    NASA Astrophysics Data System (ADS)

    de Graaf, S. E.; Danilov, A. V.; Adamyan, A.; Kubatkin, S. E.

    2013-02-01

    We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 {μ V}, approaching low enough photon population (N ˜ 1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6.4 × 10-20 F/sqrt{Hz}, limited by mechanical noise. We believe that the results presented here are a significant step towards probing quantum systems at the nanoscale using near-field scanning microwave microscopy.

  10. rRNA sequence-based scanning electron microscopic detection of bacteria.

    PubMed

    Kenzaka, Takehiko; Ishidoshiro, Ai; Yamaguchi, Nobuyasu; Tani, Katsuji; Nasu, Masao

    2005-09-01

    A new scanning electron microscopic method was developed for gaining both phylogenetic and morphological information about target microbes using in situ hybridization with rRNA-targeted oligonucleotide probes (SEM-ISH). Target cells were hybridized with oligonucleotide probes after gold labeling. Gold enhancement was used for amplification of probe signals from hybridized cells. The hybridized cells released a strong backscatter electron signal due to accumulation of gold atoms inside cells. SEM-ISH was applied to analyze bacterial community composition in freshwater samples, and bacterial cell counts determined by SEM-ISH with rRNA-targeted probes for major phyla within the domain Bacteria were highly correlated to those by fluorescent in situ hybridization (FISH). The bacterial composition on surface of river sediment particles before and after cell dispersion treatment by sonication was successfully revealed by SEM-ISH. Direct enumeration of bacterial cells on the surface of sonicated sediment particles by SEM-ISH demonstrated that members of Cytophaga-Flavobacterium existed tightly on the surface of particles. SEM-ISH allows defining the number and distribution of phylogenetically defined cells adherent to material surfaces, which is difficult in FISH, and it gives new insight into electron microscopic studies of microorganisms in their natural environment. PMID:16151145

  11. The research of infrared image enhancement algorithm based on human vision

    NASA Astrophysics Data System (ADS)

    Wang, Chen; Gao, Sili; Tang, Xinyi

    2014-11-01

    Infrared images have their own characteristics: low contrast, great noise, large dynamic range and poor visual effect. The traditional image enhancement algorithms have certain limitations and can't achieve a good visual effect. In order to obtain a good visual effect and improve the target detection and recognition capabilities, the paper studied various enhancement methods. After analyzing the retinex theory, we choose the image enhancement method based on human visual system called retinex to process infrared images. Retinex has been used to enhance the visible light image. To do experiment on infrared image enhancement, multi-scale retinex method gets ideal visual effect. On this basis, we propose an improved multi-scale Retinex (AMSR) method based on adaptive adjustment. This method can adaptively adjust the gray level and contrast of the image, enhance the details, make the weak small targets more conducive to the human eye observation. While, it is impossible to find a method suited for all infrared images with different characteristics. So, we use several traditional image enhancement algorithms to compare with the retinex algorithms. And calculate the objective evaluation factors, including average, standard deviation, entropy and so on. After observation the processing results and analyzing these evaluation factors, the AMSR algorithm is proved having its applicability and superiority. In order to select a suitable infrared image enhancement algorithms, we analyze the applicability of each enhancement methods for infrared image has obvious characteristics, To some extent, the study is significant to the infrared target detection and recognition.

  12. Infrared-sensitive electrochromic device based on VO2

    NASA Astrophysics Data System (ADS)

    Nakano, M.; Shibuya, K.; Ogawa, N.; Hatano, T.; Kawasaki, M.; Iwasa, Y.; Tokura, Y.

    2013-10-01

    The field-effect transistor (FET) provides an electrical switching function of current flowing through a channel surface by external voltage. Here, we report on a field-effect device that enables electrical switching of optical transmittance as well as conventional electrical current. We investigated optical properties of vanadium dioxide (VO2) thin film under the presence of electric field generated at the interface between VO2 and ionic liquid in a FET geometry, and found that the device exhibits clear electrochromic effect with large ON/OFF contrast only in the infrared region, potentially beneficial for energy-saving smart window applications as a voltage-tunable transparent heat-cutting filter.

  13. a Far Infrared Synchrotron-Based Investigation of 3-OXETANONE

    NASA Astrophysics Data System (ADS)

    Chen, Ziqiu; Wijngaarden, Jennifer Van

    2011-06-01

    The four membered ester ring 3-oxetanone is a precursor for adding oxetane subunits into pharmaceuticals which then block metabolically exposed sites in the bioactive molecule without increasing its lipophilicity. The high resolution (0.00096 cmCm-1) rovibrational spectrum of 3-oxetanone was recorded for the first time using far infrared radiation from the Canadian Light Source (CLS) synchrotron facility coupled to a Bruker IFS125HR FTIR spectrometer. A total of six rotationally-resolved vibrational bands were observed between 360 and 1150 cmCm-1 at room temperature. The assignment of the dense spectrum is currently underway and the progress will be discussed in this talk.

  14. Compact, light-weight and cost-effective microscope based on lensless incoherent holography for telemedicine applications.

    PubMed

    Mudanyali, Onur; Tseng, Derek; Oh, Chulwoo; Isikman, Serhan O; Sencan, Ikbal; Bishara, Waheb; Oztoprak, Cetin; Seo, Sungkyu; Khademhosseini, Bahar; Ozcan, Aydogan

    2010-06-01

    Despite the rapid progress in optical imaging, most of the advanced microscopy modalities still require complex and costly set-ups that unfortunately limit their use beyond well equipped laboratories. In the meantime, microscopy in resource-limited settings has requirements significantly different from those encountered in advanced laboratories, and such imaging devices should be cost-effective, compact, light-weight and appropriately accurate and simple to be usable by minimally trained personnel. Furthermore, these portable microscopes should ideally be digitally integrated as part of a telemedicine network that connects various mobile health-care providers to a central laboratory or hospital. Toward this end, here we demonstrate a lensless on-chip microscope weighing approximately 46 grams with dimensions smaller than 4.2 cm x 4.2 cm x 5.8 cm that achieves sub-cellular resolution over a large field of view of approximately 24 mm(2). This compact and light-weight microscope is based on digital in-line holography and does not need any lenses, bulky optical/mechanical components or coherent sources such as lasers. Instead, it utilizes a simple light-emitting-diode (LED) and a compact opto-electronic sensor-array to record lensless holograms of the objects, which then permits rapid digital reconstruction of regular transmission or differential interference contrast (DIC) images of the objects. Because this lensless incoherent holographic microscope has orders-of-magnitude improved light collection efficiency and is very robust to mechanical misalignments it may offer a cost-effective tool especially for telemedicine applications involving various global health problems in resource limited settings. PMID:20401422

  15. Compact, Light-weight and Cost-effective Microscope based on Lensless Incoherent Holography for Telemedicine Applications

    PubMed Central

    Mudanyali, Onur; Tseng, Derek; Oh, Chulwoo; Isikman, Serhan O.; Sencan, Ikbal; Bishara, Waheb; Oztoprak, Cetin; Seo, Sungkyu; Khademhosseini, Bahar; Ozcan, Aydogan

    2010-01-01

    Despite the rapid progress in optical imaging, most of the advanced microscopy modalities still require complex and costly set-ups that unfortunately limit their use beyond well equipped laboratories. In the meantime, microscopy in resource-limited settings has requirements significantly different from those encountered in advanced laboratories, and such imaging devices should be cost-effective, compact, light-weight and appropriately accurate and simple to be usable by minimally trained personnel. Furthermore, these portable microscopes should ideally be digitally integrated as part of a telemedicine network that connects various mobile health-care providers to a central laboratory or hospital. Toward this end, here we demonstrate a lensless on-chip microscope weighing ~46 grams with dimensions smaller than 4.2cm × 4.2cm × 5.8cm that achieves sub-cellular resolution over a large field of view of ~24 mm2. This compact and light-weight microscope is based on digital in-line holography and does not need any lenses, bulky optical/mechanical components or coherent sources such as lasers. Instead, it utilizes a simple light-emitting-diode (LED) and a compact opto-electronic sensor-array to record lensless holograms of the objects, which then permits rapid digital reconstruction of regular transmission or differential interference contrast (DIC) images of the objects. Because this lensless incoherent holographic microscope has orders-of-magnitude improved light collection efficiency and is very robust to mechanical misalignments it may offer a cost-effective tool especially for telemedicine applications involving various global health problems in resource limited settings. PMID:20401422

  16. The generation of infrared and ultraviolet astronomical data bases and retrieval systems

    NASA Technical Reports Server (NTRS)

    Mead, J. M.

    1985-01-01

    Observations with the Infrared Astronomy Satellite (IRAS) and with the International Ultraviolet Explorer (IUE) satellite have stimulated the need for machine-readable data bases at infrared and ultraviolet wavelengths along with associated software. This paper describes the generation of three such data sets at the Astronomical Data Center (ADC) of the NASA-Goddard Space Flight Center (GSFC): the Catalog of Infrared Observations, the Combined List of Astronomical Sources, and the Bibliographical Index of Objects Observed by IUE 1978-82. The discussion is divided by spectral regime and includes summaries of the data products developed in each category.

  17. Micromachined Electron-Tunneling Infrared Detectors

    NASA Technical Reports Server (NTRS)

    Kenny, Thomas W.; Kaiser, William J.; Waltman, Stephen B.

    1993-01-01

    Pneumatic/thermal infrared detectors based partly on Golay-cell concept, but smaller and less fragile. Include containers filled with air or other gas trapped behind diaphragms. Infrared radiation heats sensors, causing gas to expand. Resulting deflections of diaphragms measured by displacement sensors based on principle of electron-tunneling transducers of scanning tunneling microscopes. Exceed sensitivity of all other miniature, uncooled infrared sensors presently available. Expected to include low consumption of power, broadband sensitivity, room-temperature operation, and invulnerability to ionizing radiation.

  18. Real-time generation of infrared ocean scene based on GPU

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaoyi; Wang, Xun; Lin, Yun; Jin, Jianqiu

    2007-12-01

    Infrared (IR) image synthesis for ocean scene has become more and more important nowadays, especially for remote sensing and military application. Although a number of works present ready-to-use simulations, those techniques cover only a few possible ways of water interacting with the environment. And the detail calculation of ocean temperature is rarely considered by previous investigators. With the advance of programmable features of graphic card, many algorithms previously limited to offline processing have become feasible for real-time usage. In this paper, we propose an efficient algorithm for real-time rendering of infrared ocean scene using the newest features of programmable graphics processors (GPU). It differs from previous works in three aspects: adaptive GPU-based ocean surface tessellation, sophisticated balance equation of thermal balance for ocean surface, and GPU-based rendering for infrared ocean scene. Finally some results of infrared image are shown, which are in good accordance with real images.

  19. A parallel multiple path tracing method based on OptiX for infrared image generation

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Wang, Xia; Liu, Li; Long, Teng; Wu, Zimu

    2015-12-01

    Infrared image generation technology is being widely used in infrared imaging system performance evaluation, battlefield environment simulation and military personnel training, which require a more physically accurate and efficient method for infrared scene simulation. A parallel multiple path tracing method based on OptiX was proposed to solve the problem, which can not only increase computational efficiency compared to serial ray tracing using CPU, but also produce relatively accurate results. First, the flaws of current ray tracing methods in infrared simulation were analyzed and thus a multiple path tracing method based on OptiX was developed. Furthermore, the Monte Carlo integration was employed to solve the radiation transfer equation, in which the importance sampling method was applied to accelerate the integral convergent rate. After that, the framework of the simulation platform and its sensor effects simulation diagram were given. Finally, the results showed that the method could generate relatively accurate radiation images if a precise importance sampling method was available.

  20. Microscopic Polyangiitis

    PubMed Central

    Chung, Sharon A.; Seo, Philip

    2010-01-01

    Synopsis In 1923, Friedrich Wohlwill described two patients with a “microscopic form of periarteritis nodosa”, which was distinct from classical polyarteritis nodosa. This disease, now known as microscopic polyangiitis (MPA), is a primary systemic vasculitis characterized by inflammation of the small-caliber blood vessels and the presence of circulating antineutrophil cytoplasmic antibodies (ANCA). Typically, microscopic polyangiitis presents with glomerulonephritis and pulmonary capillaritis, although involvement of the skin, nerves, and gastrointestinal tract is not uncommon. Treatment of MPA generally requires use of a cytotoxic agent (such as cyclophosphamide) in addition to high-dose glucocorticoids. Recent research has focused on identifying alternate treatment strategies that minimize or eliminate exposure to cytotoxic agents. This article will review the history, pathogenesis, clinical manifestations, and treatment of MPA. PMID:20688249

  1. Characterization of exoplanet atmospheres using future space-based infrared telescopes: challenges in detecting biomarkers

    NASA Astrophysics Data System (ADS)

    Enya, Keigo

    2014-01-01

    Characterization of exoplanet atmospheres with space-based infrared telescopes is important to detect biomarkers. A promising method is temporary differential observation. For this method, designs of a wideband infrared spectral disperser are presented. A design using a CdTe prism simultaneously covers λ=1-30 μm. Designing binary pupil masks for segmented pupils to be used in spatially resolved observations are also shown for another observational method.

  2. Spatial resolution limits for synchrotron-based spectromicroscopy in the mid- and near-infrared

    SciTech Connect

    Levenson, Erika; Lerch, Philippe; Martin, Michael C.

    2008-01-12

    Spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source in Berkeley, CA, USA, a third-generation synchrotron light source. This beamline couples the high-brightness synchrotron source to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests were performed in both the mid-IR and near-IR. The results are compared with a diffraction-limited spot size theory. At shorter near-IR wavelengths the experimental results begin to deviate from diffraction-limited so a combined diffraction-limit and electron-beam-source-size model is employed. This description shows how the physical electron beam size of the synchrotron source begins to dominate the focused spot size at higher energies. The transition from diffraction-limited to electron-beam-size-limited performance is a function of storage-ring parameters and the optical demagnification within the beamline and microscope optics. The discussion includes how different facilities, beamlines and microscopes will affect the achievable spatial resolution. As synchrotron light sources and other next-generation accelerators such as energy-recovery LINACs and free-electron lasers achieve smaller beam emittances, beta-functions and/or energy spreads, diffraction-limited performance can continue to higher-energy beams, perhaps ultimately into the extreme ultraviolet.

  3. Scanning tunneling microscope based nanoscale optical imaging of molecules on surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Chen, Liuguo; Zhang, Rui; Dong, Zhenchao

    2015-08-01

    We provide an overview of the development of a merged system of low-temperature ultrahigh-vacuum scanning tunneling microscope (STM) with photon collection and detection units for optical imaging at the nanoscale. Focusing on our own work over the past ten years, the paper starts from a brief introduction of the STM induced luminescence (STML) technique and the challenge for nanoscale optical imaging, and then describes the design and instrumentation on the photon collection and detection system. The powerful potentials of the technique are illustrated using several selected examples from STML to tip enhanced Raman scattering that are mainly related to photon mapping. Such photon maps could reveal not only the local electromagnetic properties and the nature of optical transitions in the junction, but also exhibit spatial imaging resolution down to sub-molecular and sub-nanometer scale. The paper is concluded with a brief overlook on the future development of the STML technique.

  4. Relating multichannel scattering and production amplitudes in a microscopic OZI-based model

    SciTech Connect

    Beveren, Eef van Rupp, George

    2008-05-15

    Relations between scattering and production amplitudes are studied in a microscopic multichannel model for meson-meson scattering, with coupling to confined quark-antiquark channels. Overlapping resonances and a proper threshold behaviour are treated exactly in the model. Under the spectator assumption, it is found that the two-particle production amplitude shares a common denominator with the elastic scattering amplitude, besides a numerator consisting of a linear combination of all elastic and some inelastic matrix elements. The coefficients in these linear combinations are shown to be generally complex. Finally, the standard operator expressions relating production and scattering amplitudes, viz. A=T/VandIm(A)=T*A, are fulfilled, while in the small-coupling limit the usual isobar model is recovered.

  5. SPY: A new scission point model based on microscopic ingredients to predict fission fragments properties

    NASA Astrophysics Data System (ADS)

    Lemaître, J.-F.; Dubray, N.; Hilaire, S.; Panebianco, S.; Sida, J.-L.

    2013-12-01

    Our purpose is to determine fission fragments characteristics in a framework of a scission point model named SPY for Scission Point Yields. This approach can be considered as a theoretical laboratory to study fission mechanism since it gives access to the correlation between the fragments properties and their nuclear structure, such as shell correction, pairing, collective degrees of freedom, odd-even effects. Which ones are dominant in final state? What is the impact of compound nucleus structure? The SPY model consists in a statistical description of the fission process at the scission point where fragments are completely formed and well separated with fixed properties. The most important property of the model relies on the nuclear structure of the fragments which is derived from full quantum microscopic calculations. This approach allows computing the fission final state of extremely exotic nuclei which are inaccessible by most of the fission model available on the market.

  6. Using Cell-ID 1.4 with R for Microscope-Based Cytometry

    PubMed Central

    Bush, Alan; Chernomoretz, Ariel; Yu, Richard; Gordon, Andrew

    2012-01-01

    This unit describes a method for quantifying various cellular features (e.g., volume, total and subcellular fluorescence localization) from sets of microscope images of individual cells. It includes procedures for tracking cells over time. One purposefully defocused transmission image (sometimes referred to as bright-field or BF) is acquired to segment the image and locate each cell. Fluorescent images (one for each of the color channels to be analyzed) are then acquired by conventional wide-field epifluorescence or confocal microscopy. This method uses the image processing capabilities of Cell-ID (Gordon et al., 2007, as updated here) and data analysis by the statistical programming framework R (R-Development-Team, 2008), which we have supplemented with a package of routines for analyzing Cell-ID output. Both Cell-ID and the analysis package are open-source. PMID:23026908

  7. A direct micropipette-based calibration method for atomic force microscope cantilevers

    PubMed Central

    Liu, Baoyu; Yu, Yan; Yao, Da-Kang; Shao, Jin-Yu

    2009-01-01

    In this report, we describe a direct method for calibrating atomic force microscope (AFM) cantilevers with the micropipette aspiration technique (MAT). A closely fitting polystyrene bead inside a micropipette is driven by precisely controlled hydrostatic pressures to apply known loads on the sharp tip of AFM cantilevers, thus providing a calibration at the most functionally relevant position. The new method is capable of calibrating cantilevers with spring constants ranging from 0.01 to hundreds of newtons per meter. Under appropriate loading conditions, this new method yields measurement accuracy and precision both within 10%, with higher performance for softer cantilevers. Furthermore, this method may greatly enhance the accuracy and precision of calibration for colloidal probes. PMID:19566228

  8. Identification of cancerous gastric cells based on common features extracted from hyperspectral microscopic images

    PubMed Central

    Zhu, Siqi; Su, Kang; Liu, Yumeng; Yin, Hao; Li, Zhen; Huang, Furong; Chen, Zhenqiang; Chen, Weidong; Zhang, Ge; Chen, Yihong

    2015-01-01

    We construct a microscopic hyperspectral imaging system to distinguish between normal and cancerous gastric cells. We study common transmission-spectra features that only emerge when the samples are dyed with hematoxylin and eosin (H&E) stain. Subsequently, we classify the obtained visible-range transmission spectra of the samples into three zones. Distinct features are observed in the spectral responses between the normal and cancerous cell nuclei in each zone, which depend on the pH level of the cell nucleus. Cancerous gastric cells are precisely identified according to these features. The average cancer-cell identification accuracy obtained with a backpropagation algorithm program trained with these features is 95%. PMID:25909000

  9. Three-dimensional infrared imaging method based on binocular stereo vision

    NASA Astrophysics Data System (ADS)

    Sun, Junhua; Ma, Haining; Zeng, Debing

    2015-10-01

    The infrared imaging technique is characterized as high-precision and noncontact and provides the temperature information of the object, leading to its broad application in civil and military fields. Currently, the research on infrared thermography is mainly focused on two-dimensional images, lacking the information in depth orientation. To extend the range of application and provide spatial information, a three-dimensional (3-D) infrared imaging system based on binocular stereo vision is presented. The system is composed of two visible-light cameras, an infrared camera, and a digital projector. The proposed system fuses the metric information and the infrared information to acquire the 3-D surface temperature distribution by combining the 3-D reconstruction technique with infrared thermography. The registration of the metric information and the infrared image is accomplished according to the properties of three-view geometry. Experiments have been undertaken with a storage box, a rudder model, and a person's stretching arm, respectively, and the results demonstrated the good performance of the proposed method.

  10. Fast calculation of object infrared spectral scattering based on CUDA

    NASA Astrophysics Data System (ADS)

    Li, Liang-chao; Niu, Wu-bin; Wu, Zhen-sen

    2010-11-01

    Computational unified device architecture (CUDA) is used for paralleling the spectral scattering calculation from non-Lambertian object of sky and earth background irradiation. The bidirectional reflectance distribution function (BRDF) of five parameter model is utilized in object surface element scattering calculation. The calculation process is partitioned into many threads running in GPU kernel and each thread computes a visible surface element infrared spectral scattering intensity in a specific incident direction, all visible surface elements' intensity are weighted and averaged to obtain the object surface scattering intensity. The comparison of results of the CPU calculation and CUDA parallel calculation of a cylinder shows that the CUDA parallel calculation speed improves more than two hundred times in meeting the accuracy, with a high engineering value.

  11. InN Quantum Dot Based Infra-Red Photodetectors.

    PubMed

    Shetty, Arjun; Kumar, Mahesh; Roull, Basanta; Vinoy, K J; Krupanidhj, S B

    2016-01-01

    Self-assembled InN quantum dots (QDs) were grown on Si(111) substrate using plasma assisted molecular beam epitaxy (PA-MBE). Single-crystalline wurtzite structure of InN QDs was confirmed by X-ray diffraction. The dot densities were varied by varying the indium flux. Variation of dot density was confirmed by FESEM images. Interdigitated electrodes were fabricated using standard lithog- raphy steps to form metal-semiconductor-metal (MSM) photodetector devices. The devices show strong infrared response. It was found that the samples with higher density of InN QDs showed lower dark current and higher photo current. An explanation was provided for the observations and the experimental results were validated using Silvaco Atlas device simulator. PMID:27398511

  12. Near infrared plasmonic sensor based on Fano resonance

    NASA Astrophysics Data System (ADS)

    Sherif, S. M.; Shahada, L.; Zografopoulos, D. C.; Beccherelli, R.; Swillam, M.

    2016-02-01

    We introduce a compact plasmonic resonator that is capable of generating a Fano resonance in the transmission spectrum. The Fano resonance is observed with its unique lineshape. The proposed design is simple, compact, easy to fabricate and can be easily developed for different applications. The device structure is made of a gold layer, a metalinsulator- metal waveguide, and a rectangular cavity. As an application to the proposed plasmonic resonator, we introduce a gas sensor which is operational at the near infrared spectral range. The sensor possesses a high sensitivity of 1500nm/RIU at the telecom wavelength 1.55μm. FDTD simulation tools were conducted for the optimization of the device structure and obtaining the results.

  13. Raman and Infrared Absorption Study of Indigoid-based Pigments

    NASA Astrophysics Data System (ADS)

    Manciu, Felicia; Durrer, William; Reza, Layra; Ramirez, Alejandra; Chianelli, Russell

    2009-04-01

    A fascinating aspect of Maya pigments is that despite the environmentally harsh humidity and high temperatures they resist fading and they have unprecedented stability. In this investigation, we address the question of how organic dye binds to inorganic palygorskite to form pigments. Our analysis by Raman and infrared absorption spectroscopies proves that different processes are taking place for the indigo-palygorskite system as compared with the thioindigo-palygorskite complex. While partial elimination of the selection rules for the centrosymmetric indigo and disappearance of the indigo N-H bonding, with conversion to dehydroindigo, is observed for the first compound, the latter shows no evident structure modification. The interaction between indigo and palygorskite is likely through oxygen and nitrogen. Only oxygen plays this role for the thioindigo-palygorskite complex.

  14. Antimony-based superlattices for high-performance infrared imagers

    NASA Astrophysics Data System (ADS)

    Walther, Martin; Rehm, Robert; Schmitz, Johannes; Rutz, Frank; Fleissner, Joachim; Ziegler, Johann

    2008-04-01

    InAs/GaSb short-period superlattices (SL) for the fabrication of mono- and bispectral thermal imaging systems in the mid-wavelength infrared region (MWIR) have been optimized in order to increase the spectral response of the imaging systems. The responsivity in monospectral InAs/GaSb short-period superlattices increases with the number of periods in the intrinsic region of the diode and does not show a diffusion limited behavior for detector structures with up to 1000 periods. This allows the fabrication of InAs/GaSb SL camera systems with high responsivity. Dual-color MWIR/MWIR InAs/GaSb SL camera systems with high quantum efficiency for missile approach warning systems with simultaneous and spatially coincident detection in both spectral channels have been realized.

  15. Scale-space point spread function based framework to boost infrared target detection algorithms

    NASA Astrophysics Data System (ADS)

    Moradi, Saed; Moallem, Payman; Sabahi, Mohamad Farzan

    2016-07-01

    Small target detection is one of the major concern in the development of infrared surveillance systems. Detection algorithms based on Gaussian target modeling have attracted most attention from researchers in this field. However, the lack of accurate target modeling limits the performance of this type of infrared small target detection algorithms. In this paper, signal to clutter ratio (SCR) improvement mechanism based on the matched filter is described in detail and effect of Point Spread Function (PSF) on the intensity and spatial distribution of the target pixels is clarified comprehensively. In the following, a new parametric model for small infrared targets is developed based on the PSF of imaging system which can be considered as a matched filter. Based on this model, a new framework to boost model-based infrared target detection algorithms is presented. In order to show the performance of this new framework, the proposed model is adopted in Laplacian scale-space algorithms which is a well-known algorithm in the small infrared target detection field. Simulation results show that the proposed framework has better detection performance in comparison with the Gaussian one and improves the overall performance of IRST system. By analyzing the performance of the proposed algorithm based on this new framework in a quantitative manner, this new framework shows at least 20% improvement in the output SCR values in comparison with Laplacian of Gaussian (LoG) algorithm.

  16. Development of a compact low coherence interferometer based on GPGPU for fast microscopic surface measurement on turbine blades

    NASA Astrophysics Data System (ADS)

    Li, Yinan; Kästner, Markus; Reithmeier, Eduard

    2015-05-01

    Vertical scanning interferometry (VSI) techniques are widely used to profile microscopic surface structures of industrial products. This paper introduces a high-precision fast optical measurement system with an optimized small sensor head for the measurement of precision surfaces on a turbine blade or blisks (blade integrated discs). The non-contact measurement system is based on a low coherence interferometer (LCI), which is capable of fast profiling of 3D sample surface with a nanometer resolution and has a larger measurement range compared to conventional microscopes. This results in a large amount of sampled data and a high computational time for the evaluation of the data. For this reason, the used evaluation algorithm in this paper is accelerated by the Compute Unified Device Architecture (CUDA) technology, which allows parallel evaluation of the data stack on independent cores of a General Purpose Graphics Processing Unit (GPGPU). As a result, the GPU-based optimized algorithm is compared with the original CPU-based single-threaded algorithm to show the approximate 60x speedup of computing the Hilbert Transformation, which is used to find the depth position in the correlogram of each pixel of the sampled data. The main advantage of the GPU computing for the evaluation algorithm of the LCI is that it can reduce the time-consuming data evaluation process and further accelerates the whole measurement.

  17. Studies of Poly(vinyl chloride) Based Endotracheal Tubes From the Microscopic to Macroscopic Scale

    NASA Astrophysics Data System (ADS)

    Brodie, Kristin; Ortiz, Christine

    2003-03-01

    The endotracheal tube (ET) is a polymeric conduit that forms a closed system of pulmonary ventilation that is most often used to allow delivery of air to critically ill patients via intubation. Currently used ETs cause a wide variety of clinical problems including laryngeal edema (inflammation), severe morbidity, and occasionally death. To investigate the origins of this behavior, mechanical, chemical, morphological, and biocompatibility characterization of injection-molded (Endotrol) tubes of poly(vinyl chloride) (PVC) containing 35 wtplasticizer was conducted. Experiments included fourier-transform infrared spectroscopy, gel permeation chromatography, differential scanning calorimetry, accelerated solvent extraction, uniaxial tensile testing, high-resolution force spectroscopy, atomic force microscopy, and plasticizer leaching. We intend for these studies to form the basis for future ET materials selection and design.

  18. Fast approach to infrared image restoration based on shrinkage functions calibration

    NASA Astrophysics Data System (ADS)

    Zhang, Chengshuo; Shi, Zelin; Xu, Baoshu; Feng, Bin

    2016-05-01

    High-quality image restoration in real time is a challenge for infrared imaging systems. We present a fast approach to infrared image restoration based on shrinkage functions calibration. Rather than directly modeling the prior of sharp images to obtain the shrinkage functions, we calibrate them for restoration directly by using the acquirable sharp and blurred image pairs from the same infrared imaging system. The calibration method is employed to minimize the sum of squared errors between sharp images and restored images from the blurred images. Our restoration algorithm is noniterative and its shrinkage functions are stored in the look-up tables, so an architecture solution of pipeline structure can work in real time. We demonstrate the effectiveness of our approach by testing its quantitative performance from simulation experiments and its qualitative performance from a developed wavefront coding infrared imaging system.

  19. The design of real time infrared image generation software based on Creator and Vega

    NASA Astrophysics Data System (ADS)

    Wang, Rui-feng; Wu, Wei-dong; Huo, Jun-xiu

    2013-09-01

    Considering the requirement of high reality and real-time quality dynamic infrared image of an infrared image simulation, a method to design real-time infrared image simulation application on the platform of VC++ is proposed. This is based on visual simulation software Creator and Vega. The functions of Creator are introduced simply, and the main features of Vega developing environment are analyzed. The methods of infrared modeling and background are offered, the designing flow chart of the developing process of IR image real-time generation software and the functions of TMM Tool and MAT Tool and sensor module are explained, at the same time, the real-time of software is designed.

  20. Infrared image enhancement based on Riemann-Liouville fractional calculus and human visual properties

    NASA Astrophysics Data System (ADS)

    Zhang, Kai; Hao, Qun; Song, Yong; Hu, Yao

    2013-09-01

    In order to improve the definition of the infrared image, and make it more accessible for human eyes, an infrared image enhancement algorithm based on Riemann-Liouville (R-L) fractional calculus and human visual properties is proposed in this paper. Combining the mathematical model of human retinal receptive field with R-L fractional calculus theory, an R-L fractional order Rodieck enhancement mask is designed. The mask is used to enhance the textures and edges of the image. Then, the grayscales of the enhancement result are adjusted according to the grayscale resolution capabilities of human eyes. It further improves the contrast of infrared images. Experimental results show that the proposed algorithm can effectively enhance the texture details and contrast of infrared images. Compared with histogram equalization method and multi-Retinex method, the enhancement result of the proposed algorithm has better visual effect, and it is more accessible for human eyes.

  1. Infrared image non-rigid registration based on regional information entropy demons algorithm

    NASA Astrophysics Data System (ADS)

    Lu, Chaoliang; Ma, Lihua; Yu, Ming; Cui, Shumin; Wu, Qingrong

    2015-02-01

    Infrared imaging fault detection which is treated as an ideal, non-contact, non-destructive testing method is applied to the circuit board fault detection. Since Infrared images obtained by handheld infrared camera with wide-angle lens have both rigid and non-rigid deformations. To solve this problem, a new demons algorithm based on regional information entropy was proposed. The new method overcame the shortcomings of traditional demons algorithm that was sensitive to the intensity. First, the information entropy image was gotten by computing regional information entropy of the image. Then, the deformation between the two images was calculated that was the same as demons algorithm. Experimental results demonstrated that the proposed algorithm has better robustness in intensity inconsistent images registration compared with the traditional demons algorithm. Achieving accurate registration between intensity inconsistent infrared images provided strong support for the temperature contrast.

  2. High-speed atomic force microscope based on an astigmatic detection system

    SciTech Connect

    Liao, H.-S.; Chen, Y.-H.; Hwu, E.-T.; Chang, C.-S.; Hwang, I.-S.; Ding, R.-F.; Huang, H.-F.; Wang, W.-M.; Huang, K.-Y.

    2014-10-15

    High-speed atomic force microscopy (HS-AFM) enables visualizing dynamic behaviors of biological molecules under physiological conditions at a temporal resolution of 1s or shorter. A small cantilever with a high resonance frequency is crucial in increasing the scan speed. However, detecting mechanical resonances of small cantilevers is technically challenging. In this study, we constructed an atomic force microscope using a digital versatile disc (DVD) pickup head to detect cantilever deflections. In addition, a flexure-guided scanner and a sinusoidal scan method were implemented. In this work, we imaged a grating sample in air by using a regular cantilever and a small cantilever with a resonance frequency of 5.5 MHz. Poor tracking was seen at the scan rate of 50 line/s when a cantilever for regular AFM imaging was used. Using a small cantilever at the scan rate of 100 line/s revealed no significant degradation in the topographic images. The results indicate that a smaller cantilever can achieve a higher scan rate and superior force sensitivity. This work shows the potential for using a DVD pickup head in future HS-AFM technology.

  3. Microscopic basis for the band engineering of Mo1-xWxS2-based heterojunction

    NASA Astrophysics Data System (ADS)

    Yoshida, Shoji; Kobayashi, Yu; Sakurada, Ryuji; Mori, Shohei; Miyata, Yasumitsu; Mogi, Hiroyuki; Koyama, Tomoki; Takeuchi, Osamu; Shigekawa, Hidemi

    2015-10-01

    Transition-metal dichalcogenide layered materials, consisting of a transition-metal atomic layer sandwiched by two chalcogen atomic layers, have been attracting considerable attention because of their desirable physical properties for semiconductor devices, and a wide variety of pn junctions, which are essential building blocks for electronic and optoelectronic devices, have been realized using these atomically thin structures. Engineering the electronic/optical properties of semiconductors by using such heterojunctions has been a central concept in semiconductor science and technology. Here, we report the first scanning tunneling microscopy/spectroscopy (STM/STS) study on the electronic structures of a monolayer WS2/Mo1-xWxS2 heterojunction that provides a tunable band alignment. The atomically modulated spatial variation in such electronic structures, i.e., a microscopic basis for the band structure of a WS2/Mo1-xWxS2 heterojunction, was directly observed. The macroscopic band structure of Mo1-xWxS2 alloy was well reproduced by the STS spectra averaged over the surface. An electric field of as high as 80 × 106 Vm-1 was observed at the interface for the alloy with x = 0.3, verifying the efficient separation of photoexcited carriers at the interface.

  4. Computer-aided diagnosis of breast cancer based on fine needle biopsy microscopic images.

    PubMed

    Kowal, Marek; Filipczuk, Paweł; Obuchowicz, Andrzej; Korbicz, Józef; Monczak, Roman

    2013-10-01

    Prompt and widely available diagnostics of breast cancer is crucial for the prognosis of patients. One of the diagnostic methods is the analysis of cytological material from the breast. This examination requires extensive knowledge and experience of the cytologist. Computer-aided diagnosis can speed up the diagnostic process and allow for large-scale screening. One of the largest challenges in the automatic analysis of cytological images is the segmentation of nuclei. In this study, four different clustering algorithms are tested and compared in the task of fast nuclei segmentation. K-means, fuzzy C-means, competitive learning neural networks and Gaussian mixture models were incorporated for clustering in the color space along with adaptive thresholding in grayscale. These methods were applied in a medical decision support system for breast cancer diagnosis, where the cases were classified as either benign or malignant. In the segmented nuclei, 42 morphological, topological and texture features were extracted. Then, these features were used in a classification procedure with three different classifiers. The system was tested for classification accuracy by means of microscopic images of fine needle breast biopsies. In cooperation with the Regional Hospital in Zielona Góra, 500 real case medical images from 50 patients were collected. The acquired classification accuracy was approximately 96-100%, which is very promising and shows that the presented method ensures accurate and objective data acquisition that could be used to facilitate breast cancer diagnosis. PMID:24034748

  5. Low-voltage and high-performance buzzer-scanner based streamlined atomic force microscope system

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Min; Huang, Kuang-Yuh; Huang, Hsuan-Fu; Hwang, Ing-Shouh; Hwu, En-Te

    2013-11-01

    In this paper we present a novel scanner design in a quad-rod actuation structure, actuated by piezoelectric disk buzzers, and a new type of atomic force microscope (AFM), which uses this buzzer-scanner and a compact disk/digital-versatile-disk astigmatic optical pickup unit (OPU) for the detection of cantilever movements. Commercially available piezoelectric disk buzzers have a low capacitance and can be driven by low-voltage signal sources, such as analog outputs from a data acquisition card, without additional voltage or current amplifiers. Various scanning ranges can be realized through changing the dimensions of the actuation structure and/or the choice of disk buzzer. We constructed a buzzer-scanner and evaluated its performance. The scanner had a scanning range of 15 μm in the X and Y directions and an actuation range of 3.5 μm on the Z axis, with nonlinearity of 2.11%, 2.73%, and 2.19% for the X,Y and Z axes, respectively. The scanner had a resonance frequency of approximately 360 Hz on the X and Y axes, and 4.12 kHz on the Z axis. An OPU-AFM with this buzzer-scanner can resolve single atomic steps of a graphite substrate with a noise level of 0.06 nm. The obtained topographic images exhibit much less distortion than those obtained with an AFM using a piezoelectric tube scanner.

  6. Infrared thermography based studies on mobile phone induced heating

    NASA Astrophysics Data System (ADS)

    Lahiri, B. B.; Bagavathiappan, S.; Soumya, C.; Jayakumar, T.; Philip, John

    2015-07-01

    Here, we report the skin temperature rise due to the absorption of radio frequency (RF) energy from three handheld mobile phones using infrared thermography technique. Experiments are performed under two different conditions, viz. when the mobile phones are placed in soft touch with the skin surface and away from the skin surface. Additionally, the temperature rise of mobile phones during charging, operation and simultaneous charging and talking are monitored under different exposure conditions. It is observed that the temperature of the cheek and ear regions monotonically increased with time during the usage of mobile phones and the magnitude of the temperature rise is higher for the mobile phone with higher specific absorption rate. The increase in skin temperature is higher when the mobile phones are in contact with the skin surface due to the combined effect of absorption of RF electromagnetic power and conductive heat transfer. The increase in the skin temperature in non-contact mode is found to be within the safety limit of 1 °C. The measured temperature rise is in good agreement with theoretical predictions. The empirical equation obtained from the temperature rise on the cheek region of the subjects correlates well with the specific absorption rate of the mobile phones. Our study suggests that the use of mobile phones in non-contact mode can significantly lower the skin temperature rise during its use and hence, is safer compared to the contact mode.

  7. Measurement based simulation of microscope deviations for evaluation of stitching algorithms for the extension of Fourier-based alignment

    NASA Astrophysics Data System (ADS)

    Engelke, Florian; Kästner, Markus; Reithmeier, Eduard

    2013-05-01

    Image stitching is a technique used to measure large surface areas with high resolution while maintaining a large field of view. We work on improving data fusion by stitching in the field of microscopic analysis of technical surfaces for structures and roughness. Guidance errors and imaging errors such as noise cause problems for seamless image fusion of technical surfaces. The optical imaging errors of 3D Microscopes, such as confocal microscopes and white light interferometers, as well as the guidance errors of their automated positioning systems have been measured to create a software to simulate automated measurements of known surfaces with specific deviations to test new stitching algorithms. We measured and incorporated radial image distortion, interferometer reference mirror shape deviations, statistical noise, drift of the positional axis, on-axis-accuracy and repeatability of the used positioning stages and misalignment of the CCD-Chip with respect to the axes of motion. We used the resulting simulation of the measurement process to test a new image registration technique that allows for the use of correlation of images by fast fourier transform for small overlaps between single measurements.

  8. Software design of a digital holographic microscope based on MFC, multi-document and multi-thread

    NASA Astrophysics Data System (ADS)

    Zhang, Jialin; Zuo, Chao; Sun, Jiasong; Feng, Shijie; Zhang, Liguang; Fan, Yao; Hu, Yan; Kong, Fucheng; Chen, Qian; Zhang, Yuzheng; Chen, Dongdong; Tao, Tianyang; Lin, Fei; Yang, Yang; Tian, Chen

    2015-10-01

    Friendly interactive interface always significantly accelerate the progress of scientific research. However, most of the commercial softwares cannot meet the demand of a digital holographic microscope. Therefore, we designed a software in order to satisfy this requirement. We use Visual Studio 2010 to build this software, which is based on MFC multi-documents and multi-threads. The main process of designing this software is as follow: 1) Firstly, build the main frame of the software. It is easy to realize the basic interface of Windows style by programming with MFC. The most important thing in this module is adding algorithms and the functions of tool buttons to the program. 2) Secondly, implement functionality of each sub module. In this software, sub modules mainly mean sub windows. In order to have the unity of style, all sub windows use the similar toolbar. Specially, if one sub window have its own functionality, we will add button alone. 3) Thirdly, pass messages among modules. Passing messages among modules is significant in this software. The news in main program must be transmitted to the relevant sub window. The operation information in any sub windows must be transmitted to the main program, or transmitted to other sub windows. In order to make the program more efficient, we utilize multi-thread programming. With a digital holographic microscope, our software has many useful features, such as capturing the hologram of a sample (Holo View), displaying its Fourier spectrum (Fourier View), unwrapping phase map (Phase View), digital refocusing intensity information (Intensity View), drawing 2D line across the sample (2D View) and displaying three-dimensional images (Plot View). The experimental results demonstrate that a digital holographic microscope could be used much easier with the help of our software.

  9. Quantum structure based infrared detector research and development within Acreo’s centre of excellence IMAGIC

    NASA Astrophysics Data System (ADS)

    Andersson, J. Y.; Höglund, L.; Noharet, B.; Wang, Q.; Ericsson, P.; Wissmar, S.; Asplund, C.; Malm, H.; Martijn, H.; Hammar, M.; Gustafsson, O.; Hellström, S.; Radamson, H.; Holtz, P. O.

    2010-07-01

    Acreo has a long tradition of working with quantum structure based infrared (IR) detectors and arrays. This includes QWIP (quantum well infrared photodetector), QDIP (quantum dot infrared photodetector), and InAs/GaInSb based photon detectors of different structure and composition. It also covers R&D on uncooled microbolometers. The integrated thermistor material of such detectors is advantageously based on quantum structures that are optimised for high temperature coefficient and low noise. Especially the SiGe material system is preferred due to the compatibility with silicon technology. The R&D work on IR detectors is a prominent part of Acreo's centre of excellence "IMAGIC" on imaging detectors and systems for non-visible wavelengths. IMAGIC is a collaboration between Acreo, several industry partners and universities like the Royal Institute of Technology (KTH) and Linköping University.

  10. Low-voltage and high-performance buzzer-scanner based streamlined atomic force microscope system.

    PubMed

    Wang, Wei-Min; Huang, Kuang-Yuh; Huang, Hsuan-Fu; Hwang, Ing-Shouh; Hwu, En-Te

    2013-11-15

    In this paper we present a novel scanner design in a quad-rod actuation structure, actuated by piezoelectric disk buzzers, and a new type of atomic force microscope (AFM), which uses this buzzer-scanner and a compact disk/digital-versatile-disk astigmatic optical pickup unit (OPU) for the detection of cantilever movements. Commercially available piezoelectric disk buzzers have a low capacitance and can be driven by low-voltage signal sources, such as analog outputs from a data acquisition card, without additional voltage or current amplifiers. Various scanning ranges can be realized through changing the dimensions of the actuation structure and/or the choice of disk buzzer. We constructed a buzzer-scanner and evaluated its performance. The scanner had a scanning range of 15 μm in the X and Y directions and an actuation range of 3.5 μm on the Z axis, with nonlinearity of 2.11%, 2.73%, and 2.19% for the X,Y and Z axes, respectively. The scanner had a resonance frequency of approximately 360 Hz on the X and Y axes, and 4.12 kHz on the Z axis. An OPU-AFM with this buzzer-scanner can resolve single atomic steps of a graphite substrate with a noise level of 0.06 nm. The obtained topographic images exhibit much less distortion than those obtained with an AFM using a piezoelectric tube scanner. PMID:24141269

  11. Atomic force microscope based near-field imaging for probing cell surface interactions

    NASA Astrophysics Data System (ADS)

    Amini, Sina

    Near-membrane and trans-membrane proteins and their interactions with the extracellular matrix (ECM) can yield valuable information about cell dynamics. However, advances in the field of nanoscale cellular processes have been hindered, in part, due to limits imposed by current technology. In this work, a novel evanescent field (EF) imaging technique is designed, modeled, created and tested for near-field imaging in the apical surface of cells. This technique and Forster resonance energy transfer (FRET) were used to investigate interactions between integrins on the cell surface and the ECM protein, fibronectin. The goal was to monitor changes in the integrin density at the cell surface as a function of clustering after binding to fibronectin on the microsphere surface. For the EF technique, quantum dot (QD)-embedded polystyrene microspheres were used to couple light into whispering gallery modes (WGMs) inside the microspheres; the resulting EF at the surface of the microsphere was used as a near-field excitation source with ~50 nm axial resolution for exciting fluorescently-labeled integrins. For FRET measurements (~10 nm axial resolution), QDs (donors) were coated on the surface of microspheres and energy transfer to red fluorescent protein (RFP)-integrin constructs (acceptors) studied. In both techniques, the QD-modified microspheres were mounted on atomic force microscope (AFM) cantilevers, functionalized with fibronectin, and brought into contact with fluorescently-labeled HeLa or vascular smooth muscle (VSM) cells. The results obtained from both methods show the clustering and activity of the integrins and are in good agreement with each other. Amsterdam discrete dipole approximation (ADDA) was used to study the effects of inhomogeneous surrounding refractive index on the quality factor and position of the WGMs due to the attachment of a microsphere to an AFM cantilever. WGMs of various QD-embedded microspheres mounted on AFM cantilevers were experimentally

  12. Infrared image enhancement based on atmospheric scattering model and histogram equalization

    NASA Astrophysics Data System (ADS)

    Li, Yi; Zhang, Yunfeng; Geng, Aihui; Cao, Lihua; Chen, Juan

    2016-09-01

    Infrared images are fuzzy due to the special imaging technology of infrared sensor. In order to achieve contrast enhancement and gain clear edge details from a fuzzy infrared image, we propose an efficient enhancement method based on atmospheric scattering model and histogram equalization. The novel algorithm optimizes and improves the visual image haze remove method which combines the characteristics of the fuzzy infrared images. Firstly, an average filtering operation is presented to get the estimation of coarse transmission rate. Then we get the fuzzy free image through self-adaptive transmission rate calculated with the statistics information of original infrared image. Finally, to deal with low lighting problem of fuzzy free image, we propose a sectional plateau histogram equalization method which is capable of background suppression. Experimental results show that the performance and efficiency of the proposed algorithm are pleased, compared to four other algorithms in both subjective observation and objective quantitative evaluation. In addition, the proposed algorithm is competent to enhance infrared image for different applications under different circumstances.

  13. Infrared small target detection based on bilateral filtering algorithm with similarity judgments

    NASA Astrophysics Data System (ADS)

    Li, Yanbei; Li, Yan

    2014-11-01

    Infrared small target detection is part of the key technologies in infrared precision-guided, search and track system. Resulting from the relative distance of the infrared image system and the target is far, the target becomes small, faint and obscure. Furthermore, the interference of background clutter and system noise is intense. To solve the problem of infrared small target detection in a complex background, this paper proposes a bilateral filtering algorithm based on similarity judgments for infrared image background prediction. The algorithm introduces gradient factor and similarity judgment factor into traditional bilateral filtering. The two factors can enhance the accuracy of the algorithm for smooth region. At the same time, spatial proximity coefficients and gray similarity coefficient in the bilateral filtering are all expressed by the first two of McLaughlin expansion, which aiming at reducing the time overhead. Simulation results show that the proposed algorithm can effectively suppress complex background clutter in the infrared image and enhance target signal compared with the improved bilateral filtering algorithm, and it also can improve the signal to noise ratio (SNR) and contrast. Besides, this algorithm can reduce the computation time. In a word, this algorithm has a good background rejection performance.

  14. Infrared/laser multi-sensor fusion and tracking based on the multi-scale model

    NASA Astrophysics Data System (ADS)

    Wang, Bingjian; Hao, Jingya; Yi, Xiang; Wu, Feihong; Li, Min; Qin, Hanlin; Huang, Hanqiao

    2016-03-01

    The state estimation problem of targets detected by infrared/laser composite detection system with different sampling rates was studied in this paper. An effective state estimation algorithm based on data fusion is presented. Because sampling rate of infrared detection system is much higher than that of the laser detection system, the theory of multi-scale analysis is used to establish multi-scale model in this algorithm. At the fine scale, angle information provided by infrared detection system is used to estimate the target state through the unscented Kalman filter. It makes full use of the high frequency characteristic of infrared detection system to improve target state estimation accuracy. At the coarse scale, due to the sampling ratio of infrared and laser detection systems is an integer multiple, the angle information can be fused directly with the distance information of laser detection system to determine the target location. The fused information is served as observation, while the converted measurement Kalman filter (CMKF) is used to estimate the target state, which greatly reduces the complexity of filtering process and gets the optimal fusion estimation. The simulation results of tracking a target in 3-D space by infrared and laser detection systems demonstrate that the proposed algorithm in this paper is efficient and can obtain better performance than traditional algorithm.

  15. Broadband mid-infrared wavelength conversion laser based on Cr2+ doped ceramic materials

    NASA Astrophysics Data System (ADS)

    Shang, Yaping; Yin, Ke; Li, Xiao; Wang, Peng; Xu, Xiaojun

    2015-10-01

    Broadband mid-infrared lasers are desirable for pretty important applications in fields of environmental protection, medical treatment, military applications, scientific, and other domains. Recently, super-continuum laser sources have achieved striking development. However, limited by the substrate materials, the output power scaling of the broadband mid-infrared fiber laser sources could not be increased drastically, especially for the long wavelength region. In this paper, we reported an experimental study about the broadband mid-infrared lasers based on Cr2+ doped II-VI ceramic materials, by using of a super-continuum laser source developed by our groups operating at 1550~2130nm with 200mW output power. The result suggested that the near-infrared spectral component of the super-continuum source was deeply absorbed by transition metal doped zinc chalcogenides ceramic materials, meanwhile the mid-infrared part, however, had been enhanced significantly by this new "power amplifier." Actually single-pass amplification efficiency was very limited. The best way to solve this problem was multi-pass amplification systems. We had shown an initial proof of this assumption by a double-pass experiments, the result was consistent with expected effect. Above all, the spectrum shaping from short wavelength to long wavelength was obtained. The innovative discovery had laid a solid foundation for high power, high efficiency, broadly tunable mid-infrared solid state lasers.

  16. [Design and Preparation of Plant Bionic Materials Based on Optical and Infrared Features Simulation].

    PubMed

    Jiang, Xiao-jun; Lu, Xu-liang; Pan, Jia-liang; Zhang, Shuan-qin

    2015-07-01

    Due to the life characteristics such as physiological structure and transpiration, plants have unique optical and infrared features. In the optical band, because of the common effects of chlorophyll and water, plant leafs show spectral reflectance characteristics change in 550, 680, 1400 and 1900 nm significantly. In the infrared wave band, driven by transpiration, plants could regulate temperature on their own initiative, which make the infrared characteristics of plants different from artificial materials. So palnt bionic materials were proposed to simulate optical and infrared characteristics of plants. By analyzing formation mechanism of optical and infrared features about green plants, the component design and heat-transfer process of plants bionic materials were studied, above these the heat-transfer control formulation was established. Based on water adsorption/release compound, optical pigments and other man-made materials, plant bionic materials preparation methods were designed which could simulate the optical and infrared features of green plants. By chemical casting methods plant bionic material films were prepared, which use polyvinyl alcohol as film forming and water adsorption/release compound, and use optical pigments like chrome green and macromolecule yellow as colouring materials. The research conclusions achieved by testings figured out: water adsorption/release testing showed that the plant bionic materials with a certain thickness could absorb 1.3 kg water per square meter, which could satisfy the water usage of transpiration simulation one day; the optical and infrared simulated effect tests indicated that the plant bionic materials could preferably simulate the spectral reflective performance of green plants in optical wave band (380-2500 nm, expecially in 1400 and 1900 nm which were water absorption wave band of plants), and also it had similar daily infrared radiation variations with green plants, daily average radiation temperature

  17. Computerized Measuring Microscope

    NASA Astrophysics Data System (ADS)

    Schoonmaker, Thomas D.

    1980-05-01

    In the manufacturing of printed circuit boards, microscopic analysis is an essential process control activity. An inspector microscopically analyzes board samples to deter-mine board lot quality and process conditions. Prior to computerizing, this sustained measurement-taking involved the tedious process of recording raw data, converting microscope filar readings, calculating averages, logging information in a job notebook, and completing detailed final lab reports. It is evident from this brief task description that this time-consuming repetitious data recording routine was an added burden to the already fatiguing visual inspection method and therefore was a prime candidate for automatic data capture and printout. Secondly, the creation of a permanent and easily accessible data base would improve process feedback and provide for a system with quick identification of any suspect boards if further assembly/testing exhibited board-related failures. This paper describes the evolution and implementation of a computer-aided microscopic inspection operation.

  18. Validation of a fiber-based confocal microscope for interventional image-guided procedures: correlation with multispectral optical imaging

    NASA Astrophysics Data System (ADS)

    Herzka, Daniel; Quijano, Jade; Xie, Jianwu; Krueger, Sascha; Weiss, Steffen; Abrat, Benjamin; Osdoit, Anne; Cavé, Charlotte; Burnett, Christopher; Danthi, S. Narasimhan; Li, King

    2006-03-01

    The concept of the biopsy is ubiquitous in current medical diagnosis of cancer and other diseases. The standard biopsy consists of removing a sample of tissue for evaluation and diagnosis, primarily to ascertain the presence of cancer cells by (histo)pathological analyses. However, the advent of new optical imaging modalities and targeted or "smart" agents, that have affinity for a select target, suggests the possibility of performing in vivo tissue characterization without the need for sample removal or the wait for histopathologic processing. Here we present work testing and validating a fiber-based confocal fluorescence microscopic imaging system intended for combination with a larger scale imaging modality (i.e. MRI or CT) to be used in image-guided in vivo tissue characterization. Fiber-based confocal fluorescence microscopic imaging experiments were performed (Cellvizio, Mauna Kea Technologies, Paris, France) in vivo in two mouse models including: 1) EGFP-expressing mouse melanoma model and 2) M21 mouse melanoma model. Both models are known to express integrin α νβ 3, a cell-surface receptor protein. We also performed an experiment in ex vivo chicken muscle tissue labelled with a fluorescein isothiocyanate-lectin targeted compound. In the mouse models, contrast agents that targeted the integrin were injected and the contrast agent localization in tumor was verified by a whole-body multispectral imager. The fiber-based tool was sensitive enough to detect and image the tissue of interest in all different experiments, and was found appropriate for use in interventional catheter-based procedures.

  19. A quantitative microscopic approach to predict local recurrence based on in vivo intraoperative imaging of sarcoma tumor margins.

    PubMed

    Mueller, Jenna L; Fu, Henry L; Mito, Jeffrey K; Whitley, Melodi J; Chitalia, Rhea; Erkanli, Alaattin; Dodd, Leslie; Cardona, Diana M; Geradts, Joseph; Willett, Rebecca M; Kirsch, David G; Ramanujam, Nimmi

    2015-11-15

    The goal of resection of soft tissue sarcomas located in the extremity is to preserve limb function while completely excising the tumor with a margin of normal tissue. With surgery alone, one-third of patients with soft tissue sarcoma of the extremity will have local recurrence due to microscopic residual disease in the tumor bed. Currently, a limited number of intraoperative pathology-based techniques are used to assess margin status; however, few have been widely adopted due to sampling error and time constraints. To aid in intraoperative diagnosis, we developed a quantitative optical microscopy toolbox, which includes acriflavine staining, fluorescence microscopy, and analytic techniques called sparse component analysis and circle transform to yield quantitative diagnosis of tumor margins. A series of variables were quantified from images of resected primary sarcomas and used to optimize a multivariate model. The sensitivity and specificity for differentiating positive from negative ex vivo resected tumor margins was 82 and 75%. The utility of this approach was tested by imaging the in vivo tumor cavities from 34 mice after resection of a sarcoma with local recurrence as a bench mark. When applied prospectively to images from the tumor cavity, the sensitivity and specificity for differentiating local recurrence was 78 and 82%. For comparison, if pathology was used to predict local recurrence in this data set, it would achieve a sensitivity of 29% and a specificity of 71%. These results indicate a robust approach for detecting microscopic residual disease, which is an effective predictor of local recurrence. PMID:25994353

  20. Improvements to a Grating-Based Spectral Imaging Microscope and Its Application to Reflectance Analysis of Blue Pen Inks.

    PubMed

    McMillan, Leilani C; Miller, Kathleen P; Webb, Michael R

    2015-08-01

    A modified design of a chromatically resolved optical microscope (CROMoscope), a grating-based spectral imaging microscope, is described. By altering the geometry and adding a beam splitter, a twisting aberration that was present in the first version of the CROMoscope has been removed. Wavelength adjustment has been automated to decrease analysis time. Performance of the new design in transmission-absorption spectroscopy has been evaluated and found to be generally similar to the performance of the previous design. Spectral bandpass was found to be dependent on the sizes of apertures, and the smallest measured spectral bandpass was 1.8 nm with 1.0 mm diameter apertures. Wavelength was found to be very linear with the sine of the grating angle (R(2) = 0.9999995), and wavelength repeatability was found to be much better than the spectral bandpass. Reflectance spectral imaging with a CROMoscope is reported for the first time, and this reflectance spectral imaging was applied to blue ink samples on white paper. As a proof of concept, linear discriminant analysis was used to classify the inks by brand. In a leave-one-out cross-validation, 97.6% of samples were correctly classified. PMID:26162719

  1. Hybrid PSO-ASVR-based method for data fitting in the calibration of infrared radiometer

    NASA Astrophysics Data System (ADS)

    Yang, Sen; Li, Chengwei

    2016-06-01

    The present paper describes a hybrid particle swarm optimization-adaptive support vector regression (PSO-ASVR)-based method for data fitting in the calibration of infrared radiometer. The proposed hybrid PSO-ASVR-based method is based on PSO in combination with Adaptive Processing and Support Vector Regression (SVR). The optimization technique involves setting parameters in the ASVR fitting procedure, which significantly improves the fitting accuracy. However, its use in the calibration of infrared radiometer has not yet been widely explored. Bearing this in mind, the PSO-ASVR-based method, which is based on the statistical learning theory, is successfully used here to get the relationship between the radiation of a standard source and the response of an infrared radiometer. Main advantages of this method are the flexible adjustment mechanism in data processing and the optimization mechanism in a kernel parameter setting of SVR. Numerical examples and applications to the calibration of infrared radiometer are performed to verify the performance of PSO-ASVR-based method compared to conventional data fitting methods.

  2. Image processing system design for microcantilever-based optical readout infrared arrays

    NASA Astrophysics Data System (ADS)

    Tong, Qiang; Dong, Liquan; Zhao, Yuejin; Gong, Cheng; Liu, Xiaohua; Yu, Xiaomei; Yang, Lei; Liu, Weiyu

    2012-12-01

    Compared with the traditional infrared imaging technology, the new type of optical-readout uncooled infrared imaging technology based on MEMS has many advantages, such as low cost, small size, producing simple. In addition, the theory proves that the technology's high thermal detection sensitivity. So it has a very broad application prospects in the field of high performance infrared detection. The paper mainly focuses on an image capturing and processing system in the new type of optical-readout uncooled infrared imaging technology based on MEMS. The image capturing and processing system consists of software and hardware. We build our image processing core hardware platform based on TI's high performance DSP chip which is the TMS320DM642, and then design our image capturing board based on the MT9P031. MT9P031 is Micron's company high frame rate, low power consumption CMOS chip. Last we use Intel's company network transceiver devices-LXT971A to design the network output board. The software system is built on the real-time operating system DSP/BIOS. We design our video capture driver program based on TI's class-mini driver and network output program based on the NDK kit for image capturing and processing and transmitting. The experiment shows that the system has the advantages of high capturing resolution and fast processing speed. The speed of the network transmission is up to 100Mbps.

  3. Hybrid PSO-ASVR-based method for data fitting in the calibration of infrared radiometer.

    PubMed

    Yang, Sen; Li, Chengwei

    2016-06-01

    The present paper describes a hybrid particle swarm optimization-adaptive support vector regression (PSO-ASVR)-based method for data fitting in the calibration of infrared radiometer. The proposed hybrid PSO-ASVR-based method is based on PSO in combination with Adaptive Processing and Support Vector Regression (SVR). The optimization technique involves setting parameters in the ASVR fitting procedure, which significantly improves the fitting accuracy. However, its use in the calibration of infrared radiometer has not yet been widely explored. Bearing this in mind, the PSO-ASVR-based method, which is based on the statistical learning theory, is successfully used here to get the relationship between the radiation of a standard source and the response of an infrared radiometer. Main advantages of this method are the flexible adjustment mechanism in data processing and the optimization mechanism in a kernel parameter setting of SVR. Numerical examples and applications to the calibration of infrared radiometer are performed to verify the performance of PSO-ASVR-based method compared to conventional data fitting methods. PMID:27370427

  4. Small Infrared Target Detection by Region-Adaptive Clutter Rejection for Sea-Based Infrared Search and Track

    PubMed Central

    Kim, Sungho; Lee, Joohyoung

    2014-01-01

    This paper presents a region-adaptive clutter rejection method for small target detection in sea-based infrared search and track. In the real world, clutter normally generates many false detections that impede the deployment of such detection systems. Incoming targets (missiles, boats, etc.) can be located in the sky, horizon and sea regions, which have different types of clutters, such as clouds, a horizontal line and sea-glint. The characteristics of regional clutter were analyzed after the geometrical analysis-based region segmentation. The false detections caused by cloud clutter were removed by the spatial attribute-based classification. Those by the horizontal line were removed using the heterogeneous background removal filter. False alarms by sun-glint were rejected using the temporal consistency filter, which is the most difficult part. The experimental results of the various cluttered background sequences show that the proposed region adaptive clutter rejection method produces fewer false alarms than that of the mean subtraction filter (MSF) with an acceptable degradation detection rate. PMID:25054633

  5. Small infrared target detection by region-adaptive clutter rejection for sea-based infrared search and track.

    PubMed

    Kim, Sungho; Lee, Joohyoung

    2014-01-01

    This paper presents a region-adaptive clutter rejection method for small target detection in sea-based infrared search and track. In the real world, clutter normally generates many false detections that impede the deployment of such detection systems. Incoming targets (missiles, boats, etc.) can be located in the sky, horizon and sea regions, which have different types of clutters, such as clouds, a horizontal line and sea-glint. The characteristics of regional clutter were analyzed after the geometrical analysis-based region segmentation. The false detections caused by cloud clutter were removed by the spatial attribute-based classification. Those by the horizontal line were removed using the heterogeneous background removal filter. False alarms by sun-glint were rejected using the temporal consistency filter, which is the most difficult part. The experimental results of the various cluttered background sequences show that the proposed region adaptive clutter rejection method produces fewer false alarms than that of the mean subtraction filter (MSF) with an acceptable degradation detection rate. PMID:25054633

  6. A graphene-based Fabry-Pérot spectrometer in mid-infrared region

    PubMed Central

    Wang, Xiaosai; Chen, Chen; Pan, Liang; Wang, Jicheng

    2016-01-01

    Mid-infrared spectroscopy is of great importance in many areas and its integration with thin-film technology can economically enrich the functionalities of many existing devices. In this paper we propose a graphene-based ultra-compact spectrometer (several micrometers in size) that is compatible with complementary metal-oxide-semiconductor (CMOS) processing. The proposed structure uses a monolayer graphene as a mid-infrared surface waveguide, whose optical response is spatially modulated using electric fields to form a Fabry-Pérot cavity. By varying the voltage acting on the cavity, we can control the transmitted wavelength of the spectrometer at room temperature. This design has potential applications in the graphene-silicon-based optoelectronic devices as it offers new possibilities for developing new ultra-compact spectrometers and low-cost hyperspectral imaging sensors in mid-infrared region. PMID:27573080

  7. An infrared image super-resolution reconstruction method based on compressive sensing

    NASA Astrophysics Data System (ADS)

    Mao, Yuxing; Wang, Yan; Zhou, Jintao; Jia, Haiwei

    2016-05-01

    Limited by the properties of infrared detector and camera lens, infrared images are often detail missing and indistinct in vision. The spatial resolution needs to be improved to satisfy the requirements of practical application. Based on compressive sensing (CS) theory, this thesis presents a single image super-resolution reconstruction (SRR) method. With synthetically adopting image degradation model, difference operation-based sparse transformation method and orthogonal matching pursuit (OMP) algorithm, the image SRR problem is transformed into a sparse signal reconstruction issue in CS theory. In our work, the sparse transformation matrix is obtained through difference operation to image, and, the measurement matrix is achieved analytically from the imaging principle of infrared camera. Therefore, the time consumption can be decreased compared with the redundant dictionary obtained by sample training such as K-SVD. The experimental results show that our method can achieve favorable performance and good stability with low algorithm complexity.

  8. A graphene-based Fabry-Pérot spectrometer in mid-infrared region.

    PubMed

    Wang, Xiaosai; Chen, Chen; Pan, Liang; Wang, Jicheng

    2016-01-01

    Mid-infrared spectroscopy is of great importance in many areas and its integration with thin-film technology can economically enrich the functionalities of many existing devices. In this paper we propose a graphene-based ultra-compact spectrometer (several micrometers in size) that is compatible with complementary metal-oxide-semiconductor (CMOS) processing. The proposed structure uses a monolayer graphene as a mid-infrared surface waveguide, whose optical response is spatially modulated using electric fields to form a Fabry-Pérot cavity. By varying the voltage acting on the cavity, we can control the transmitted wavelength of the spectrometer at room temperature. This design has potential applications in the graphene-silicon-based optoelectronic devices as it offers new possibilities for developing new ultra-compact spectrometers and low-cost hyperspectral imaging sensors in mid-infrared region. PMID:27573080

  9. Research on power measurement device of jamming bomb based on Infrared Radiation

    NASA Astrophysics Data System (ADS)

    Chang, Shuai; Tong, Shoufeng; Song, Yansong; Dong, Yan

    2013-12-01

    In order to realize the non-connect measurement on the power and character of jamming bomb, we carried out the research on power measurement device of jamming bomb based on Infrared Radiation. First, the power and infrared radiant band of the jamming bomb was summarized and refined. Then, ensuring the feature and power of jamming bomb was characterized by the magnitude of Infrared Radiation. Afterwards, based on the theory of the above, a power measurement device of Infrared Radiation was simulated and developed. Including the selection of detector and the detector application design, analog signal processing and digital signal processing, using correlation measurement method to detect and calculate the power of device. Finally, the specific method and advantage of the device was introduced. The results of the experiment show that: the response time of the device is less than 3ms; the detection sensitivity is better than 3 x 108cm √HZ / W . The device successfully accomplished the accuracy measurement of Infrared Radiation between 1 to 20um wavelength with higher detection sensitivity and lower response time.

  10. Analysis of biofluids in aqueous environment based on mid-infrared spectroscopy.

    PubMed

    Fabian, Heinz; Lasch, Peter; Naumann, Dieter

    2005-01-01

    In this study we describe a semiautomatic Fourier transform infrared spectroscopic methodology for the analysis of liquid serum samples, which combines simple sample introduction with high sample throughput. The applicability of this new infrared technology to the analysis of liquid serum samples from a cohort of cattle naturally infected with bovine spongiform encephalopathy and from controls was explored in comparison to the conventional approach based on transmission infrared spectroscopy of dried serum films. Artifical neural network analysis of the infrared data was performed to differentiate between bovine spongiform encephalopathy-negative controls and animals in the late stage of the disease. After training of artifical neural network classifiers, infrared spectra of sera from an independent external validation data set were analyzed. In this way, sensitivities between 90 and 96% and specificities between 84 and 92% were achieved, respectively, depending upon the strategy of data collection and data analysis. Based on these results, the advantages and limitations of the liquid sample technique and the dried film approach for routine analysis of biofluids are discussed. PMID:16229628

  11. Infrared and multi-type images fusion algorithm based on contrast pyramid transform

    NASA Astrophysics Data System (ADS)

    Xu, Hua; Wang, Yan; Wu, Yujing; Qian, Yunsheng

    2016-09-01

    A fusion algorithm for infrared and multi-type images based on contrast pyramid transform (CPT) combined with Otsu method and morphology is proposed in this paper. Firstly, two sharpened images are combined to the first fused image based on information entropy weighted scheme. Afterwards, two enhanced images and the first fused one are decomposed into a series of images with different dimensions and spatial frequencies. To the low-frequency layer, the Otsu method is applied to calculate the optimal segmentation threshold of the first fused image, which is subsequently used to determine the pixel values in top layer fused image. With respect to the high-frequency layers, the top-bottom hats morphological transform is employed to each layer before maximum selection criterion. Finally, the series of decomposed images are reconstructed and then superposed with the enhanced image processed by morphological gradient operation as a second fusion to get the final fusion image. Infrared and visible images fusion, infrared and low-light-level (LLL) images fusion, infrared intensity and infrared polarization images fusion, and multi-focus images fusion are discussed in this paper. Both experimental results and objective metrics demonstrate the effectiveness and superiority of the proposed algorithm over the conventional ones used to compare.

  12. Binary mixtures of rod-like colloids under shear: microscopically-based equilibrium theory and order-parameter dynamics

    NASA Astrophysics Data System (ADS)

    Lugo-Frías, Rodrigo; Klapp, Sabine H. L.

    2016-06-01

    This paper is concerned with the dynamics of a binary mixture of rod-like, repulsive colloidal particles driven out of equilibrium by means of a steady shear flow (Couette geometry). To this end we first derive, starting from a microscopic density functional in Parsons–Lee approximation, a mesoscopic free energy functional whose main variables are the orientational order parameter tensors. Based on this mesoscopic functional we then explore the stability of isotropic and nematic equilibrium phases in terms of composition and rod lengths. Second, by combining the equilibrium theory with the Doi–Hess approach for the order parameter dynamics under shear, we investigate the orientational dynamics of binary mixtures for a range of shear rates and coupling parameters. We find a variety of dynamical states, including synchronized oscillatory states of the two components, but also symmetry breaking behavior where the components display different in-plane oscillatory states.

  13. Binary mixtures of rod-like colloids under shear: microscopically-based equilibrium theory and order-parameter dynamics.

    PubMed

    Lugo-Frías, Rodrigo; Klapp, Sabine H L

    2016-06-22

    This paper is concerned with the dynamics of a binary mixture of rod-like, repulsive colloidal particles driven out of equilibrium by means of a steady shear flow (Couette geometry). To this end we first derive, starting from a microscopic density functional in Parsons-Lee approximation, a mesoscopic free energy functional whose main variables are the orientational order parameter tensors. Based on this mesoscopic functional we then explore the stability of isotropic and nematic equilibrium phases in terms of composition and rod lengths. Second, by combining the equilibrium theory with the Doi-Hess approach for the order parameter dynamics under shear, we investigate the orientational dynamics of binary mixtures for a range of shear rates and coupling parameters. We find a variety of dynamical states, including synchronized oscillatory states of the two components, but also symmetry breaking behavior where the components display different in-plane oscillatory states. PMID:27115342

  14. Sensitivity analysis of rectangular atomic force microscope cantilevers immersed in liquids based on the modified couple stress theory.

    PubMed

    Lee, Haw-Long; Chang, Win-Jin

    2016-01-01

    The modified couple stress theory is adopted to study the sensitivity of a rectangular atomic force microscope (AFM) cantilever immersed in acetone, water, carbon tetrachloride (CCl4), and 1-butanol. The theory contains a material length scale parameter and considers the size effect in the analysis. However, this parameter is difficult to obtain via experimental measurements. In this study, a conjugate gradient method for the parameter estimation of the frequency equation is presented. The optimal method provides a quantitative approach for estimating the material length scale parameter based on the modified couple stress theory. The results show that the material length scale parameter of the AFM cantilever immersed in acetone, CCl4, water, and 1-butanol is 0, 25, 116.3, and 471 nm, respectively. In addition, the vibration sensitivities of the AFM cantilever immersed in these liquids are investigated. The results are useful for the design of AFM cantilevers immersed in liquids. PMID:26402914

  15. Infrared detection with colloidal quantum dots based on interband and intraband transitions

    NASA Astrophysics Data System (ADS)

    Guyot-Sionnest, Philippe

    2015-03-01

    While much research on colloidal quantum dots is focused on their potential as visible emitter or light harvester, this talk will cover our investigations of the mercury chalcogenide colloidal quantum dots in the thermal mid-infrared ranges of 3-5 microns and 8-12 microns where the atmosphere is transparent. HgTe is a zero-gap semiconductor. As a result, colloidal quantum dots (CQD) of sizes between 10 and 20 nm readily lead to infrared gaps tuning between 3 and 12 microns respectively. It is also very promising that infrared photodetection using dried films of these CQDs has now been demonstrated up to 12 microns. Further improvement through chemistry are likely and will be required to raise the detectivity to the level required to transform thermal infrared detection technology. In contrast to HgTe CQDs which tend to be intrinsic, beta-HgS and HgSe CQDs are naturally n-doped, in the first such instance with CQDs. Furthermore, the doping is modulated by modifying the surface composition, and this effect is attributed to the tuning of the energy level with respect to the environment, via the surface electrostatics. With controlled doping, both HgSe and HgS CQDs have now led to the first operation of mid-infrared CQD photodetector based on the intraband absorption. This is a breakthrough in the field of colloidal quantum dots where interband transitions had been exclusively used for the past 30 years. One challenge with both interband and intraband infrared CQDs will be to reduce the nonradiative recombination, which will improve the detectivity as well as allow to use their infrared luminescence.

  16. In situ microparticle analysis of marine phytoplankton cells with infrared laser-based optical tweezers

    NASA Astrophysics Data System (ADS)

    Sonek, G. J.; Liu, Y.; Iturriaga, R. H.

    1995-11-01

    We describe the application of infrared optical tweezers to the in situ microparticle analysis of marine phytoplankton cells. A Nd:YAG laser (lambda=3D 1064 nm) trap is used to confine and manipulate single Nannochloris and Synechococcus cells in an enriched seawater medium while spectral fluorescence and Lorenz-Mie backscatter signals are simultaneously acquired under a variety of excitation and trapping conditions. Variations in the measured fluorescence intensities of chlorophyll a (Chl a) and phycoerythrin pigments in phytoplankton cells are observed. These variations are related, in part, to basic intrasample variability, but they also indicate that increasing ultraviolet-exposure time and infrared trapping power may have short-term effects on cellular physiology that are related to Chl a photobleaching and laser-induced heating, respectively. The use of optical tweezers to study the factors that affect marine cell physiology and the processes of absorption, scattering, and attenuation by individual cells, organisms, and particulate matter that contribute to optical closure on a microscopic scale are also described. (c)1995 Optical Society of America

  17. Dynamic simulation of infrared signature of deep groove ball bearing based on ANSYS/LS-DYNA

    NASA Astrophysics Data System (ADS)

    Kou, Wei; Yang, Li; Hong, Yixun

    2015-10-01

    The dynamic simulation of infrared signature of the deep groove ball bearing (DGBB) was carried out based on ANSYS/LS-DYNA. A finite element model of the ball-raceway contact of the was established, and the slide friction between the ball and the raceway was considered as the main reason of heat generation, and the impacts of radial load, rotation speed and the coefficient of friction to the heat generation and the infrared characteristics of distribution were discussed in detail. The relative errors between the simulation results and the theoretical calculation value are less than 10%, which proves this simulation model is accurate and reliable.

  18. Flexible infrared detectors based on p-n junctions of multi-walled carbon nanotubes.

    PubMed

    Huang, Zhenlong; Gao, Min; Yan, Zhuocheng; Pan, Taisong; Liao, Feiyi; Lin, Yuan

    2016-05-14

    Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT p-n junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm(-2) even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors. PMID:27101973

  19. "Key to Freshwater Algae": A Web-Based Tool to Enhance Understanding of Microscopic Biodiversity

    ERIC Educational Resources Information Center

    Shayler, Hannah A.; Siver, Peter A.

    2006-01-01

    The Freshwater Ecology Laboratory at Connecticut College has developed an interactive, Web-based identification key to freshwater algal genera using the Lucid Professional and Lucid 3 software developed by the Centre for Biological Information Technology at the University of Queensland, Brisbane, Australia. The "Key to Freshwater Algae" was funded…

  20. Advancements in quantum cascade laser-based infrared microscopy of aqueous media.

    PubMed

    Haase, K; Kröger-Lui, N; Pucci, A; Schönhals, A; Petrich, W

    2016-06-23

    The large mid-infrared absorption coefficient of water frequently hampers the rapid, label-free infrared microscopy of biological objects in their natural aqueous environment. However, the high spectral power density of quantum cascade lasers is shifting this limitation such that mid-infrared absorbance images can be acquired in situ within signal-to-noise ratios of up to 100. Even at sample thicknesses well above 50 μm, signal-to-noise ratios above 10 are readily achieved. The quantum cascade laser-based microspectroscopy of aqueous media is exemplified by imaging an aqueous yeast solution and quantifying glucose consumption, ethanol generation as well as the production of carbon dioxide gas during fermentation. PMID:27032367

  1. Collecting, analyzing and archiving of ground based infrared solar spectra obtained from several locations

    NASA Technical Reports Server (NTRS)

    Murcray, David G.; Murcray, Frank J.; Goldman, Aaron; Mcelroy, Charles T.; Chu, William P.; Rinsland, Curtis P.; Woods, Peter; Matthews, W. A.; Johnston, P. V.

    1990-01-01

    The infrared solar spectrum as observed from the ground under high resolution contains thousands of absorption lines. The majority of these lines are due to compounds that are present in the Earth's atmosphere. Ground based infrared solar spectra contain information concerning the composition of the atmosphere at the time the spectra were obtained. The objective of this program is to record solar spectra from various ground locations, and to analyze and archive these spectra. The analysis consists of determining, for as many of the absorption lines as possible, the molecular species responsible for the absorption, and to verify that current models of infrared transmission match the observed spectra. Archiving is an important part of the program, since a number of the features in the spectra have not been identified. At some later time, when the features are identified, it will be possible to determine the amount of that compound that was present in the atmosphere at the time the spectrum was taken.

  2. Infrared moving point target detection based on spatial-temporal local contrast filter

    NASA Astrophysics Data System (ADS)

    Deng, Lizhen; Zhu, Hu; Tao, Chao; Wei, Yantao

    2016-05-01

    Infrared moving point target detection is a challenging task. In this paper, we define a novel spatial local contrast (SLC) and a novel temporal local contrast (TLC) to enhance the target's contrast. Based on the defined spatial local contrast and temporal local contrast, we propose a simple but powerful spatial-temporal local contrast filter (STLCF) to detect moving point target from infrared image sequences. In order to verify the performance of spatial-temporal local contrast filter on detecting moving point target, different detection methods are used to detect the target from several infrared image sequences for comparison. The experimental results show that the proposed spatial-temporal local contrast filter has great superiority in moving point target detection.

  3. Dissolved Gas-in-Oil Analysis in Transformers Based on Near-Infrared Photoacoustic Spectroscopy

    NASA Astrophysics Data System (ADS)

    Mao, Xuefeng; Zhou, Xinlei; Zhai, Liang; Yu, Qingxu

    2015-06-01

    This paper investigates an application of near-infrared photoacoustic spectroscopy (PAS) to analyze the dissolved gas-in-oil of a transformer. A near-infrared tunable fiber laser-based PAS system has been developed. Using this system, the gas detection limits (signal-to-noise ratio = 1) of 4 ppb at 1531.59 nm for , 39 ppm at 1565.98 nm for CO, and 34 ppm at 1572.34 are reached. In addition, the fault gas () is produced by a transformer spatial discharge simulation system, and the productivity of the gas is measured quantitatively. The experiment demonstrates the near-infrared PAS system is able to be applied to the dissolved gas analysis of a transformer.

  4. Visible and infrared multispectral illumination concept based on Galilean collimation systems: IACATS illumination source

    NASA Astrophysics Data System (ADS)

    Ramos Zapata, Gonzalo; Belenguer Dávila, Tomás; Pastor Santos, Carmen; Restrepo Gómez, René; González Alvarado, Concepción; Laguna Hernández, Hugo; Astolfi Carbonell, Antonio; Moreno Raso, Javier; Argelaguet, Heribert; Serrano, Javier

    2010-07-01

    A LED based illumination system in which five Galilean collimation systems have been used is reported on. It is part of a turbulence simulator for the evaluation of on ground telescopes instrumentation developed by INTA (optics) and LIDAX (opto-mechanics) for the IAC called IACATS. The illumination requirements (some visible and infrared lines) allow the use of five different LEDs (red, green, blue and two infrareds). In order to optimize the illumination level of each wavelength, a Galilean collimating optical configuration was constructed for each wavelength channel. The IACATS instrument simulates a scene consisting of a set of different binary stars simulating the required angular separation between them, ant their spectral characteristics. As a result, a visible and infrared multi-spectral illumination system has been integrated as a part of the turbulence simulator, and the features (opto-mechanical) and illumination characteristics are described in the following lines.

  5. Evaluation of paint coating thickness variations based on pulsed Infrared thermography laser technique

    NASA Astrophysics Data System (ADS)

    Mezghani, S.; Perrin, E.; Vrabie, V.; Bodnar, J. L.; Marthe, J.; Cauwe, B.

    2016-05-01

    In this paper, a pulsed Infrared thermography technique using a homogeneous heat provided by a laser source is used for the non-destructive evaluation of paint coating thickness variations. Firstly, numerical simulations of the thermal response of a paint coated sample are performed. By analyzing the thermal responses as a function of thermal properties and thickness of both coating and substrate layers, optimal excitation parameters of the heating source are determined. Two characteristic parameters were studied with respect to the paint coating layer thickness variations. Results obtained using an experimental test bench based on the pulsed Infrared thermography laser technique are compared with those given by a classical Eddy current technique for paint coating variations from 5 to 130 μm. These results demonstrate the efficiency of this approach and suggest that the pulsed Infrared thermography technique presents good perspectives to characterize the heterogeneity of paint coating on large scale samples with other heating sources.

  6. Architecture and performance of the space-based Far-Infrared Interferometer Instrument Simulator

    NASA Astrophysics Data System (ADS)

    Juanola-Parramon, R.; Fenech, D. M.; Savini, G.

    2016-04-01

    FIRI (Far Infra-Red Interferometer) is a spatial and spectral space interferometer with an operating wavelength range of 25-400 μm and sub-arcsecond angular resolution. It is based on the combination of stellar interferometry and Fourier transform spectroscopy to perform spectroscopy at high angular resolution in the far-infrared. The resulting technique is referred to as double Fourier spatio-spectral interferometry. With increased spatial and spectral resolution come a number of interesting science cases such as the formation and evolution of AGN and the characterization of gas, ice and dust in discs undergoing planetary formation, among others. To study the feasibility of a FIRI system, the Far-Infrared Interferometer Instrument Simulator (FIInS) has been developed. With FIInS, once a set of modelled scientific data is available, one can compare an input sky map with the synthesized one after data reduction algorithms have been applied.

  7. Phase-locked, erbium-fiber-laser-based frequency comb in the near infrared.

    PubMed

    Washburn, Brian R; Diddams, Scott A; Newbury, Nathan R; Nicholson, Jeffrey W; Yan, Man F; Jørgensen, Carsten G

    2004-02-01

    A phase-locked frequency comb in the near infrared is demonstrated with a mode-locked, erbium-doped, fiber laser whose output is amplified and spectrally broadened in dispersion-flattened, highly nonlinear optical fiber to span from 1100 to >2200 nm. The supercontinuum output comprises a frequency comb with a spacing set by the laser repetition rate and an offset by the carrier-envelope offset frequency, which is detected with the standard f-to-2f heterodyne technique. The comb spacing and offset frequency are phase locked to a stable rf signal with a fiber stretcher in the laser cavity and by control of the pump laser power, respectively. This infrared comb permits frequency metrology experiments in the near infrared in a compact, fiber-laser-based system. PMID:14759041

  8. 1Click1View: Interactive Visualization Methodology for RNAi Cell-Based Microscopic Screening

    PubMed Central

    Zwolinski, Lukasz; Kozak, Marta; Kozak, Karol

    2013-01-01

    Technological advancements are constantly increasing the size and complexity of data resulting from large-scale RNA interference screens. This fact has led biologists to ask complex questions, which the existing, fully automated analyses are often not adequate to answer. We present a concept of 1Click1View (1C1V) as a methodology for interactive analytic software tools. 1C1V can be applied for two-dimensional visualization of image-based screening data sets from High Content Screening (HCS). Through an easy-to-use interface, one-click, one-view concept, and workflow based architecture, visualization method facilitates the linking of image data with numeric data. Such method utilizes state-of-the-art interactive visualization tools optimized for fast visualization of large scale image data sets. We demonstrate our method on an HCS dataset consisting of multiple cell features from two screening assays. PMID:23484084

  9. A Multiscale Model Based On Intragranular Microstructure — Prediction Of Dislocation Patterns At The Microscopic Scale

    NASA Astrophysics Data System (ADS)

    Franz, Gérald; Abed-Meraim, Farid; Zineb, Tarak Ben; Lemoine, Xavier; Berveiller, Marcel

    2007-04-01

    A large strain elastic-plastic single crystal constitutive law, based on dislocation annihilation and storage, is implemented in a new self-consistent scheme, leading to a multiscale model which achieves, for each grain, the calculation of plastic slip activity, with help of regularized formulation drawn from visco-plasticity, and dislocation microstructure evolution. This paper focuses on the relationship between the deformation history of a BCC grain and induced microstructure during monotonic and two-stage strain paths.

  10. Infrared image guidance for ground vehicle based on fast wavelet image focusing and tracking

    NASA Astrophysics Data System (ADS)

    Akiyama, Akira; Kobayashi, Nobuaki; Mutoh, Eiichiro; Kumagai, Hideo; Yamada, Hirofumi; Ishii, Hiromitsu

    2009-08-01

    We studied the infrared image guidance for ground vehicle based on the fast wavelet image focusing and tracking. Here we uses the image of the uncooled infrared imager mounted on the two axis gimbal system and the developed new auto focusing algorithm on the Daubechies wavelet transform. The developed new focusing algorithm on the Daubechies wavelet transform processes the result of the high pass filter effect to meet the direct detection of the objects. This new focusing gives us the distance information of the outside world smoothly, and the information of the gimbal system gives us the direction of objects in the outside world to match the sense of the spherical coordinate system. We installed this system on the hand made electric ground vehicle platform powered by 24VDC battery. The electric vehicle equips the rotary encoder units and the inertia rate sensor units to make the correct navigation process. The image tracking also uses the developed newt wavelet focusing within several image processing. The size of the hand made electric ground vehicle platform is about 1m long, 0.75m wide, 1m high, and 50kg weight. We tested the infrared image guidance for ground vehicle based on the new wavelet image focusing and tracking using the electric vehicle indoor and outdoor. The test shows the good results by the developed infrared image guidance for ground vehicle based on the new wavelet image focusing and tracking.

  11. A model for μ-biomimetic thermal infrared sensors based on the infrared receptors of Melanophila acuminata.

    PubMed

    Siebke, Georg; Holik, Peter; Schmitz, Sam; Schmitz, Helmut; Lacher, Manfred; Steltenkamp, Siegfried

    2014-09-01

    Beetles of the genus Melanophila acuminata detect forest fires from distances as far as 130 km with infrared-sensing organs. Inspired by this extremely sensitive biological device, we are developing an IR sensor that operates at ambient temperature using MEMS technology. The sensor consists of two liquid-filled chambers that are connected by a micro-fluidic system. Absorption of IR radiation by one of these chambers leads to heating and expansion of a liquid. The increasing pressure deflects a membrane covered by one electrode of a plate capacitor. The micro-fluidic system and the second chamber represent a fluidic low-pass filter, preventing slow, but large pressure changes. However, the strong frequency dependence of the filter demands a precise characterization of its properties. Here, we present a theoretical model that describes the frequency-dependent response of the sensor based on material properties and geometrical dimensions. Our model is divided into four distinct parts that address different aspects of the sensor. The model describes the frequency-dependent behaviour of the fluidic filter and a thermal low-pass filter as well as saturation effects at low frequencies. This model allows the calculation of optimal design parameters, and thereby provides the foundation for the development of such a sensor. PMID:24762777

  12. Dynamic infrared scene projectors based upon the DMD

    NASA Astrophysics Data System (ADS)

    Beasley, D. Brett; Bender, Matt; Crosby, Jay; Messer, Tim

    2009-02-01

    The Micromirror Array Projector System (MAPS) is an advanced dynamic scene projector system developed by Optical Sciences Corporation (OSC) for Hardware-In-the-Loop (HWIL) simulation and sensor test applications. The MAPS is based upon the Texas Instruments Digital Micromirror Device (DMD) which has been modified to project high resolution, realistic imagery suitable for testing sensors and seekers operating in the UV, visible, NIR, and IR wavebands. Since the introduction of the first MAPS in 2001, OSC has continued to improve the technology and develop systems for new projection and Electro-Optical (E-O) test applications. This paper reviews the basic MAPS design and performance capabilities. We also present example projectors and E-O test sets designed and fabricated by OSC in the last 7 years. Finally, current research efforts and new applications of the MAPS technology are discussed.

  13. Near infrared spectroscopy for fibre based gas detection

    NASA Astrophysics Data System (ADS)

    Stewart, George; Johnstone, Walter; Thursby, Graham; Culshaw, Brian

    2010-04-01

    Gas sensing systems based on fibre optic linked near infra red absorption cells are potentially a flexible and effective tool for monitoring accumulations of hazardous and noxious gases in enclosed areas such as tunnels and mines. Additionally the same baseline technology is readily modified to measure concentrations of hydrocarbon fuels - notably but not exclusively methane, and monitoring emissions of greenhouse gases. Furthermore the system can be readily implemented to provide intrinsically safe monitoring over extensive areas at up to ~250 points from a single interrogation unit. In this paper we review our work on fibre coupled gas sensing systems. We outline the basic principles through which repeatable and accurate self calibrating gas measurements may be realised, including the recover of detailed line shapes for non contact temperature and / or pressure measurements in addition to concentration assessments in harsh environments. We also outline our experience in using these systems in extensive networks operating under inhospitable conditions over extended periods extending to several years.

  14. Assessment of starch-based wood adhesive quality by confocal Raman microscopic detection of reaction homogeneity.

    PubMed

    Wang, Panjun; Cheng, Li; Gu, Zhengbiao; Li, Zhaofeng; Hong, Yan

    2015-10-20

    Confocal Raman microscopy (CRM) was used to detect the reaction homogeneity of vinyl acetate grafted on starch granules and help to assess the quality of high solid content starch-based wood adhesive (HSSWA). Primarily, four experimental starch samples were investigated, and by analysis of band area ratio (carbonyl/carbohydrate) of each granule, information about reaction homogeneity was collected. The results showed that reaction extent and homogeneity were inconsistent for samples with different G values, and the distribution of ester groups on blend samples was much less uniform than grafted starch samples with the same G value, confirming that CRM was useful for determining the homogeneity of chemical modification. Afterwards, the technique was applied to research HSSWA prepared by two-stage seeded polymerization and traditional process. The distribution of ester groups was more uniform among starch granules prepared by former method, resulted in adhesive with much better performance, indicating that uniformity of polymerization was an important factor related to properties of starch-based wood adhesive. PMID:26256162

  15. Regression models based on new local strategies for near infrared spectroscopic data.

    PubMed

    Allegrini, F; Fernández Pierna, J A; Fragoso, W D; Olivieri, A C; Baeten, V; Dardenne, P

    2016-08-24

    In this work, a comparative study of two novel algorithms to perform sample selection in local regression based on Partial Least Squares Regression (PLS) is presented. These methodologies were applied for Near Infrared Spectroscopy (NIRS) quantification of five major constituents in corn seeds and are compared and contrasted with global PLS calibrations. Validation results show a significant improvement in the prediction quality when local models implemented by the proposed algorithms are applied to large data bases. PMID:27496996

  16. System design and new applications for atomic force microscope based on tunneling

    NASA Astrophysics Data System (ADS)

    Wang, X.; Liu, A. P.; Yang, X. H.

    2015-09-01

    The design of atomic force microscopy (AFM) with high resolution is introduced in this paper. Mainly, we have developed the system design of the apparatus based on tunneling. AFM.IPC-208B, this kind of apparatus combines scanning tunnel microscopy (STM) and AFM availability, and its lens body with original frame enhances the capability of the machine. In order to analyze the performance of AFM.IPC-208B, as a new tool in the field of Life Science, we make use of the system to study natural mica and molecular protein structures of Cattle-insulin and human antibody immunoglobulin G (IgG) coupled with staphylococcus protein A (SPA). As the results of new applications, the resolution of AFM.IPC-208B is proved to be 0.1 nm, and these nanometer measurement results provide much valuable information for the study of small molecular proteins and HIV experiments.

  17. Analysis of Video-Based Microscopic Particle Trajectories Using Kalman Filtering

    PubMed Central

    Wu, Pei-Hsun; Agarwal, Ashutosh; Hess, Henry; Khargonekar, Pramod P.; Tseng, Yiider

    2010-01-01

    Abstract The fidelity of the trajectories obtained from video-based particle tracking determines the success of a variety of biophysical techniques, including in situ single cell particle tracking and in vitro motility assays. However, the image acquisition process is complicated by system noise, which causes positioning error in the trajectories derived from image analysis. Here, we explore the possibility of reducing the positioning error by the application of a Kalman filter, a powerful algorithm to estimate the state of a linear dynamic system from noisy measurements. We show that the optimal Kalman filter parameters can be determined in an appropriate experimental setting, and that the Kalman filter can markedly reduce the positioning error while retaining the intrinsic fluctuations of the dynamic process. We believe the Kalman filter can potentially serve as a powerful tool to infer a trajectory of ultra-high fidelity from noisy images, revealing the details of dynamic cellular processes. PMID:20550894

  18. Observation of electrodeposited lithium by optical microscope in room temperature ionic liquid-based electrolyte

    NASA Astrophysics Data System (ADS)

    Sano, H.; Sakaebe, H.; Matsumoto, H.

    Room temperature ionic liquids (RTILs) were applied to a lithium (Li) metal battery system, and the behavior of Li electrodeposition on nickel electrodes in RTILs was investigated using in situ optical microscopy with/without an organic additive, vinylene carbonate (VC), in the RTILs. Two RTILs, PP13[TFSA] (N-methyl- N-propylpiperidinium bis(trifluoromethanesulfonyl)amide) and EMI[FSA] (1-ethyl-3-methylimidazolium bis(fluorosulfonyl)amide), were chosen as the base electrolytes. Dendritic particles were obtained in the case of EMI[FSA] with and without VC, and PP13[TFSA] without VC, while non-dendritic fine particles were obtained in the case of PP13[TFSA] with VC.

  19. A Novel Atomic Force Microscope Control System Based on PC104 and DSP Embedded System

    NASA Astrophysics Data System (ADS)

    Yin, Bohua; Chen, Daixie; Lin, Yunsheng; Chu, Mingzhang; Han, Li

    In order to achieve large scanning range, this article presents a new type high-speed AFM system. According to the need of rapid data transmission and operation, the AFM control system structure was composed of PC104 and DSP hardware model. Because of using a large displacement flexure stage as the sample stage, this AFM system is capable of providing a scan range of 100×100um image with 50 Hz line-scan speed. The capacitor displacement sensors are used as x-y position during AFM scan image. We realized a new scanning method based on positioning control. The scanning images are more precision and less distortion than general open-loop x-y scanning image.

  20. Penetration of resin-based materials into initial erosion lesion: A confocal microscopic study.

    PubMed

    Ionta, Franciny Querobim; Boteon, Ana Paula; Moretto, Marcelo Juliano; Júnior, Odair Bim; Honório, Heitor Marques; Silva, Thiago Cruvinel; Wang, Linda; Rios, Daniela

    2016-02-01

    The application of resin-based materials is an alternative of treatment for eroded lesions. Nevertheless, there are no studies about the penetration of these materials into eroded lesion, which might affect its adhesion. Therefore, this study evaluated the penetration of four resin-based materials, with and without enamel etching. By using an in vitro protocol, types of treatment were studied at five levels (AdheSE(®) , Tetric N-Bond(®) , Single Bond 2(®) , Helioseal Clear(®) , Icon(®) ) and types of enamel etching in two levels (with and without). Materials were stained with 0.02 mg/mL ethanolic solution of tetramethylrhodamine isothiocyanate. Bovine enamel samples (4 × 4 mm) were immersed in 0.01 M HCl, pH 2.3, for 30 seconds to produce initial eroded lesions. Afterward, the materials were applied on half of sample enamel surface following the manufacturer's instructions. On the other half of sample, the materials were applied without etching the enamel. Materials penetration into the enamel was assessed by Confocal Laser Scanning Microscopy on reflection and fluorescence modes. The penetration depth (PD) was measured using ImageJ software. Data were analyzed by two-way ANOVA and Tukey test (P < 0.05). Regardless of the material, etched enamel resulted in higher PD than non-etched (P < 0.05). Icon(®) showed the highest PD in enamel followed by Helioseal Clear(®) (P < 0.05), with significant difference between them (P < 0.05) and no difference was found among AdheSE(®) , Tetric N-Bond(®) , and Single Bond 2(®) (P > 0.05). It can be concluded that prior enamel etching increased the materials penetration into eroded enamel and the Icon(®) -infiltrant presented highest penetration. PMID:26626706

  1. Microscopic origin of read current noise in TaOx-based resistive switching memory by ultra-low temperature measurement

    NASA Astrophysics Data System (ADS)

    Pan, Yue; Cai, Yimao; Liu, Yefan; Fang, Yichen; Yu, Muxi; Tan, Shenghu; Huang, Ru

    2016-04-01

    TaOx-based resistive random access memory (RRAM) attracts considerable attention for the development of next generation nonvolatile memories. However, read current noise in RRAM is one of the critical concerns for storage application, and its microscopic origin is still under debate. In this work, the read current noise in TaOx-based RRAM was studied thoroughly. Based on a noise power spectral density analysis at room temperature and at ultra-low temperature of 25 K, discrete random telegraph noise (RTN) and continuous average current fluctuation (ACF) are identified and decoupled from the total read current noise in TaOx RRAM devices. A statistical comparison of noise amplitude further reveals that ACF depends strongly on the temperature, whereas RTN is independent of the temperature. Measurement results combined with conduction mechanism analysis show that RTN in TaOx RRAM devices arises from electron trapping/detrapping process in the hopping conduction, and ACF is originated from the thermal activation of conduction centers that form the percolation network. At last, a unified model in the framework of hopping conduction is proposed to explain the underlying mechanism of both RTN and ACF noise, which can provide meaningful guidelines for designing noise-immune RRAM devices.

  2. Automatic visible and infrared face registration based on silhouette matching and robust transformation estimation

    NASA Astrophysics Data System (ADS)

    Tian, Tian; Mei, Xiaoguang; Yu, Yang; Zhang, Can; Zhang, Xiaoye

    2015-03-01

    Registration of multi-sensor data (particularly visible color sensors and infrared sensors) is a prerequisite for multimodal image analysis such as image fusion. In this paper, we proposed an automatic registration technique for visible and infrared face images based on silhouette matching and robust transformation estimation. The key idea is to represent a (visible or infrared) face image by its silhouette which is extracted from the image's edge map and consists of a set of discrete points, and then align the two silhouette point sets by using their feature similarity and spatial geometrical information. More precisely, our algorithm first matches the silhouette point sets by their local shape features such as shape context, which creates a set of putative correspondences that may contaminated by outliers. Next, we estimate the accurate transformation from the putative correspondence set under a robust maximum likelihood framework combining with the EM algorithm, where the transformation between the image pair is modeled by a parametric model such as the rigid or affine transformation. The qualitative and quantitative comparisons on a publicly available database demonstrate that our method significantly outperforms other state-of-the-art visible/infrared face registration methods. As a result, our method will be beneficial for fusion-based face recognition.

  3. Research on the controlling thermal defocus aberration for the infrared imaging system based on wavefront coding

    NASA Astrophysics Data System (ADS)

    Chen, Di; Dong, Liquan; Zhao, Yuejin; Liu, Xiaohua; Li, Cuiling; Guo, Xiaohu; Zhao, Zhu; Wu, Yijian

    2014-09-01

    We describe the application of wavefront coding technique for infrared imaging system to control thermal defocus. For traditional infrared imaging system, athermalization is necessary to maintain imaging performance which may increase complexity and cost of the imaging system. Wavefront coding includes a phase mask at the pupil which can re-modulate wave front so as to produce an encoded image. After digital processing, the system is insensitive to defocus. In this paper, the combination of wavefront coding technique and infrared imaging system has been discussed. We report here the optic design of the wavefront coding IR system based on Zemax. The phase mask is designed to ensure that the modulation transfer function (MTF) is approximately invariant in the range of working temperature. Meanwhile, we designed three IR systems to put up contrast experiments. System one and two are designed to compare the influence before and after the insertion of phase mask. System three is designed to compare the imaging performance before and after reducing lens in wavefront coding IR system. The simulation results show that the infrared imaging system based on wavefront coding can control thermal defocus in a temperature varying from -60ºC to 60 ºC, at the same time the weight and cost of optical elements are reduced by approximately 40%.

  4. Fusion of infrared and visible images based on saliency scale-space in frequency domain

    NASA Astrophysics Data System (ADS)

    Chen, Yanfei; Sang, Nong; Dan, Zhiping

    2015-12-01

    A fusion algorithm of infrared and visible images based on saliency scale-space in the frequency domain was proposed. Focus of human attention is directed towards the salient targets which interpret the most important information in the image. For the given registered infrared and visible images, firstly, visual features are extracted to obtain the input hypercomplex matrix. Secondly, the Hypercomplex Fourier Transform (HFT) is used to obtain the salient regions of the infrared and visible images respectively, the convolution of the input hypercomplex matrix amplitude spectrum with a low-pass Gaussian kernel of an appropriate scale which is equivalent to an image saliency detector are done. The saliency maps are obtained by reconstructing the 2D signal using the original phase and the amplitude spectrum, filtered at a scale selected by minimizing saliency map entropy. Thirdly, the salient regions are fused with the adoptive weighting fusion rules, and the nonsalient regions are fused with the rule based on region energy (RE) and region sharpness (RS), then the fused image is obtained. Experimental results show that the presented algorithm can hold high spectrum information of the visual image, and effectively get the thermal targets information at different scales of the infrared image.

  5. Model based on-chip 13bits ADC design dedicated to uncooled infrared focal plane arrays

    NASA Astrophysics Data System (ADS)

    Dupont, Benoit; Robert, Patrick; Dupret, Antoine; Villard, Patrick; Pochic, David

    2007-10-01

    This paper presents an on-chip 13 bits 10 M/S Analog to Digital Converter (ADC) specifically designed for infrared bolometric image sensor. Bolometric infrared sensors are MEMs based thermal sensors, which covers a large spectrum of infrared applications, ranging from night vision to predictive industrial maintenance and medical imaging. With the current move towards submicron technologies, the demand for more integrated, smarter sensors and microsystems has dramatically increased. This trend has strengthened the need of on-chip ADC as the interface between the analog core and the digital processing electronic. However designing an on-chip ADC dedicated to focal plane array raises many questions about its architecture and its performance requirements. To take into account those specific needs, a high level model has been developed prior to the actual design. In this paper, we present the trade-offs of ADC design linked to infrared key performance parameters and bolometric technology detection method. The original development scheme, based on system level modeling, is also discussed. Finally we present the actual design and the measured performances.

  6. Gaussian mixture model-based gradient field reconstruction for infrared image detail enhancement and denoising

    NASA Astrophysics Data System (ADS)

    Zhao, Fan; Zhao, Jian; Zhao, Wenda; Qu, Feng

    2016-05-01

    Infrared images are characterized by low signal-to-noise ratio and low contrast. Therefore, the edge details are easily immerged in the background and noise, making it much difficult to achieve infrared image edge detail enhancement and denoising. This article proposes a novel method of Gaussian mixture model-based gradient field reconstruction, which enhances image edge details while suppressing noise. First, by analyzing the gradient histogram of noisy infrared image, Gaussian mixture model is adopted to simulate the distribution of the gradient histogram, and divides the image information into three parts corresponding to faint details, noise and the edges of clear targets, respectively. Then, the piecewise function is constructed based on the characteristics of the image to increase gradients of faint details and suppress gradients of noise. Finally, anisotropic diffusion constraint is added while visualizing enhanced image from the transformed gradient field to further suppress noise. The experimental results show that the method possesses unique advantage of effectively enhancing infrared image edge details and suppressing noise as well, compared with the existing methods. In addition, it can be used to effectively enhance other types of images such as the visible and medical images.

  7. Flexible infrared detectors based on p-n junctions of multi-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Huang, Zhenlong; Gao, Min; Yan, Zhuocheng; Pan, Taisong; Liao, Feiyi; Lin, Yuan

    2016-05-01

    Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT p-n junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm-2 even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors.Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT p-n junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm-2 even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08791k

  8. Microscopic biomineralization processes and Zn bioavailability: a synchrotron-based investigation of Pistacia lentiscus L. roots.

    PubMed

    De Giudici, G; Medas, D; Meneghini, C; Casu, M A; Gianoncelli, A; Iadecola, A; Podda, S; Lattanzi, P

    2015-12-01

    Plants growing on polluted soils need to control the bioavailability of pollutants to reduce their toxicity. This study aims to reveal processes occurring at the soil-root interface of Pistacia lentiscus L. growing on the highly Zn-contaminated tailings of Campo Pisano mine (SW Sardinia, Italy), in order to shed light on possible mechanisms allowing for plant adaptation. The study combines conventional X-ray diffraction (XRD) and scanning electron microscopy (SEM) with advanced synchrotron-based techniques, micro-X-ray fluorescence mapping (μ-XRF) and X-ray absorption spectroscopy (XAS). Data analysis elucidates a mechanism used by P. lentiscus L. as response to high Zn concentration in soil. In particular, P. lentiscus roots take up Al, Si and Zn from the rhizosphere minerals in order to build biomineralizations that are part of survival strategy of the species, leading to formation of a Si-Al biomineralization coating the root epidermis. XAS analysis rules out Zn binding to organic molecules and indicates that Zn coordinates Si atoms stored in root epidermis leading to the precipitation of an amorphous Zn-silicate. These findings represent a step forward in understanding biological mechanisms and the resulting behaviour of minor and trace elements during plant-soil interaction and will have significant implications for development of phytoremediation techniques. PMID:26062465

  9. New Kohn-Sham density functional based on microscopic nuclear and neutron matter equations of state

    NASA Astrophysics Data System (ADS)

    Baldo, M.; Robledo, L. M.; Schuck, P.; Viñas, X.

    2013-06-01

    A new version of the Barcelona-Catania-Paris energy functional is applied to a study of nuclear masses and other properties. The functional is largely based on calculated ab initio nuclear and neutron matter equations of state. Compared to typical Skyrme functionals having 10-12 parameters apart from spin-orbit and pairing terms, the new functional has only 2 or 3 adjusted parameters, fine tuning the nuclear matter binding energy and fixing the surface energy of finite nuclei. An energy rms value of 1.58 MeV is obtained from a fit of these three parameters to the 579 measured masses reported in the Audi and Wapstra [Nucl. Phys. ANUPABL0375-947410.1016/j.nuclphysa.2003.11.003 729, 337 (2003)] compilation. This rms value compares favorably with the one obtained using other successful mean field theories, which range from 1.5 to 3.0 MeV for optimized Skyrme functionals and 0.7 to 3.0 for the Gogny functionals. The other properties that have been calculated and compared to experiment are nuclear radii, the giant monopole resonance, and spontaneous fission lifetimes.

  10. Immobilized diaphorase surfaces observed by scanning electrochemical microscope with shear force based tip-substrate positioning.

    PubMed

    Yamada, Hiroshi; Fukumoto, Hikaru; Yokoyama, Tetsuya; Koike, Tohru

    2005-03-15

    Imaging of a coimmobilized diaphorase and albumin surface was investigated by scanning electrochemical microscopy (SECM) with shear force based tip-substrate distance control. A microelectrode tip was attached to a commercially available tuning fork to detect the shear force between the microelectrode tip and the surface. We used the standing approach mode, which repeats an approach and retraction at each data point of the surface to obtain simultaneous current and topographic images. To check the performance of our SECM system, we imaged a platinum-patterned array electrode and a diaphorase/albumin coimmobilized glass surface. Since the system acquires current when the tip is retracted to a desired distance, this mode is useful for a relatively large microelectrode (approximately 10 microm) and for scanning a large area (few hundreds of micrometers). Furthermore, by retracting the tip when the tip moves laterally to the next data point to avoid contact between the tip and sample surface, we successfully imaged the surface without destroying its morphology. PMID:15762586

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  12. Antimony-based materials for infrared photodetectors: Growth, characterization, fabrication, and analysis

    NASA Astrophysics Data System (ADS)

    Michel, Erick John

    Sb-based materials are investigated for infrared photodetectors capable of performance comparable or better than that of industry standard material systems such as mercury cadmium telluride (MCT) or Si microbolometers. The materials were grown by solid source molecular beam epitaxy on high quality, less expensive, large area substrate material such as GaAs and Si. InSb was grown on 3″ GaAs substrates with material quality approaching that of bulk material as assessed using structural, electrical, and optical measurements. X-ray diffraction full widths at half maximum (FWHM) of ˜50 arcsec, electron mobilities of 125,000 cm2/V-s at 200K, and PL linewidths of ˜18 meV were obtained for InSb epilayers on GaAs. In collaboration with an industrial partner, infrared imaging was obtained for the first time from heteroepitaxial InSb. A 256 x 256 array was bump bonded to a Si CMOS readout circuit resulting in infrared thermal imaging. By incorporating As into the InSb lattice, the cutoff wavelength can be extended out to ˜12 mum at 300K. There is interest in infrared detectors that can operate in the long wavelength range without the need for cryogenic or thermoelectric cooling. Eliminating the cooling system improves reliability, decreases cost, and simplifies the overall system design. The main competitors to InAsSb are MCT and Si microbolometers. Although Si microbolometers achieve adequate detectivities at room temperature, the speed of the detector is not fast enough for applications such as projectile fuzes. MCT is capable of high speed operation with detectivities in the 10 8 cm-Hz1/2/W range at 300K. However MCT suffers from material problems such as instability during growth and fabrication due to the ionic bonding of this II--VI material, as well as the very sharp dependence of cutoff wavelength on composition in the long wavelength infrared range. For these reasons, InAsSb has been investigated for uncooled infrared detector applications. Infrared detectors

  13. Three-dimensional image cytometer based on a high-speed two-photon scanning microscope

    NASA Astrophysics Data System (ADS)

    Kim, Ki H.; Stitt, Molly S.; Hendricks, Carrie A.; Almeida, Karen H.; Engelward, Bevin P.; So, Peter T. C.

    2001-04-01

    We developed a 3-D image cytometer based on two-photon scanning microscopy. The system keeps the inherent advantages from two-photon scanning microscopy: (1) The ability of imaging thick tissue samples up to a few hundred micrometers, (2) The ability to study tissue structures with subcellular resolution, (3) The ability to monitor tissue biochemistry and metabolism, and (4) The reduction of specimen photobleaching and photodamage. Therefore, 3-D image cytometer has the ability to characterize multiple cell layer specimens, in contrast with 2-D image cytometer where only single cell layer samples can be imaged. 3-D image cytometry increases its frame rate by adapting a polygonal mirror scanner and high-speed photomultiplier tubes. The current frame rate is 13 frames per second. High throughput rate is achieved by imaging multiple cell layer specimens in 3-D at a high frame rate. The throughput rate of this system is dependent on the choice of objective lenses, specimen properties, and the speed of computer-controlled specimen stage. It can be up to approximately 100 cells per second which is comparable with that of 2-D image cytometers. With the high throughput rate and deep tissue imaging capability, 3-D image cytometer has the potential for the detection of rare cellular events inside living, intact tissues. A promising application of this 3-D image cytometer is the study of mitotic recombination in tissues. Mitotic recombination is a mechanism for genetic change. Therefore it is one of causes for carcinogenesis. However, the study of this process is difficult because recombination event is rare and it occurs at a rate of one cell in 105 cells. The new method for the study is (1) to engineer transgenic mice whose cells will express fluorescence in the presence of mitotic recombination, (2) to detect cells which have undergone mitotic recombination with 3-D image cytometry. The estimated time required to quantify spontaneous recombination rate is approximately

  14. A pressure gauge based on gas density measurement from analysis of the thermal noise of an atomic force microscope cantilever

    SciTech Connect

    Seo, Dongjin; Ducker, William A.; Paul, Mark R.

    2012-05-15

    We describe a gas-density gauge based on the analysis of the thermally-driven fluctuations of an atomic force microscope (AFM) cantilever. The fluctuations are modeled as a ring-down of a simple harmonic oscillator, which allows fitting of the resonance frequency and damping of the cantilever, which in turn yields the gas density. The pressure is obtained from the density using the known equation of state. In the range 10-220 kPa, the pressure readings from the cantilever gauge deviate by an average of only about 5% from pressure readings on a commercial gauge. The theoretical description we use to determine the pressure from the cantilever motion is based upon the continuum hypothesis, which sets a minimum pressure for our analysis. It is anticipated that the cantilever gauge could be extended to measure lower pressures given a molecular theoretical description. Alternatively, the gauge could be calibrated for use in the non-continuum range. Our measurement technique is similar to previous AFM cantilever measurements, but the analysis produces improved accuracy.

  15. Parallel algorithm of real-time infrared image restoration based on total variation theory

    NASA Astrophysics Data System (ADS)

    Zhu, Ran; Li, Miao; Long, Yunli; Zeng, Yaoyuan; An, Wei

    2015-10-01

    Image restoration is a necessary preprocessing step for infrared remote sensing applications. Traditional methods allow us to remove the noise but penalize too much the gradients corresponding to edges. Image restoration techniques based on variational approaches can solve this over-smoothing problem for the merits of their well-defined mathematical modeling of the restore procedure. The total variation (TV) of infrared image is introduced as a L1 regularization term added to the objective energy functional. It converts the restoration process to an optimization problem of functional involving a fidelity term to the image data plus a regularization term. Infrared image restoration technology with TV-L1 model exploits the remote sensing data obtained sufficiently and preserves information at edges caused by clouds. Numerical implementation algorithm is presented in detail. Analysis indicates that the structure of this algorithm can be easily implemented in parallelization. Therefore a parallel implementation of the TV-L1 filter based on multicore architecture with shared memory is proposed for infrared real-time remote sensing systems. Massive computation of image data is performed in parallel by cooperating threads running simultaneously on multiple cores. Several groups of synthetic infrared image data are used to validate the feasibility and effectiveness of the proposed parallel algorithm. Quantitative analysis of measuring the restored image quality compared to input image is presented. Experiment results show that the TV-L1 filter can restore the varying background image reasonably, and that its performance can achieve the requirement of real-time image processing.

  16. System design and description of infrared simulator system based on the multidimensional flight table

    NASA Astrophysics Data System (ADS)

    Huang, Chong; Chen, Haiqing; Li, Jun; Yang, Zhengang; Zhao, Shuang

    2008-12-01

    This paper deals with the simulation for the army aviation and missile command at the thermal infrared range scale from 2.0 to 4.9μm. The infrared simulator system based on the multidimensional flight table(ISSBMFT) is the significant part of hardware - in - the - loop (HWIL) simulation system for controlling and guiding weapon systems with infrared seekers. It emphasizes on the infrared scene of HWIL simulation experimentation for controlling and guiding weapon and provides a realistic environment of combat with target/jamming which owns the specific properties of radiant spectrum, entrance angle and target's relative distance variation. Optical system is the basis of the characteristics of the simulator. In the system, three-beam structure is put forward which will make the optical path equal. Through settling attenuators, filters, and polaroids in the beams, which modulates the transmittance, the energy proportion is simulated, so as wave energy and the entrance angle. So we can simulate one target and two different forms of jamming through various distance and conformations. Radiant system and controlling system is the guarantee of the simulation. Calculation of energy and the method of controlling is depicted in the article.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  19. Statistical Retrieval of Thin Liquid Cloud Microphysical Properties Using Ground-Based Infrared and Microwave Observations

    NASA Astrophysics Data System (ADS)

    Marke, Tobias; Löhnert, Ulrich; Ebell, Kerstin; Turner, David D.

    2016-04-01

    In this study, liquid water cloud microphysical properties are retrieved by exploiting passive remote sensing techniques in the microwave and infrared spectral regime. Liquid water clouds are highly frequent in various climate regimes and play a significant role in terms of interaction with radiation. Small perturbations in the amount of liquid water contained in the cloud can cause large variations in the radiative fluxes. This effect enhances for thin clouds with a low liquid water path (LWP), which requires accurate retrieval information on the cloud properties. Retrieving low LWP values using the microwave spectral regime reveals large relative errors, whereas the potential for infrared methods is high. Therefore robust and computationally low demanding synergistic retrievals based on a multivariate regression and a neural network are derived to estimate LWP and cloud effective radius. While the regression-type synergy retrievals are strongly influenced by the nonlinearities of saturating signals in the infrared regime for higher LWP, the neural network retrieval is able to retrieve LWP and cloud effective radius with a higher accuracy than the single instrument retrievals. This is achieved by examining synthetic observations in the low LWP range. Furthermore, the performance of the retrievals is assessed in a radiative closure study for the downwelling shortwave flux, using measurements of a microwave radiometer, a broadband infrared radiometer and a spectrally highly resolved Atmospheric Emitted Radiance Interferometer (AERI).

  20. A visible/infrared gray image fusion algorithm based on the YUV color transformation

    NASA Astrophysics Data System (ADS)

    Zhu, Jin; Jin, Weiqi; Li, Jiakun; Li, Li

    2012-11-01

    Color fusion technology, one of the typical technologies, has been emphasized all over the world. Multiband images are fused into a color image. Some effective visible and thermal infrared color fusion algorithms have been proposed now. We have successfully run a real-time natural sense of visible/infrared color fusion algorithm in DSP and FPGA hardware processing platforms. However, according to different needs, gray image fusion technology has its own unique applications. Based on the natural sense of color image fusion algorithm of the visible and infrared, we have proposed a visible / infrared gray image fusion algorithm. Firstly we do a YUV color fusion. Then we output the brightness of the fusion as gray fusion images. This algorithm for image fusion is compared with typical fusion algorithms: the weighted average, the Laplace Pyramid and the Haar basis wavelet. Several objective evaluation indicators are selected. The results of objective and subjective comparison show that the algorithm has most advantages. It shows that multiband gray image fusion in the color space is available. The algorithm is implemented on a DSP hardware image processing platform real-time with the TI's chip as the kernel processor. It makes natural sense of color fusion and gray fusion for visible light (low level light) and thermal imaging integrated. Users are convenient to choose model of the natural sense of color fusion or gray fusion for real-time video imaging output

  1. Semiconductor up-converter based on cascade carrier transport for infrared detection/imaging

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Hao, Zhi-Biao; Luo, Yi; Kang, Jian-Bin; Wang, Lai; Xiong, Bing; Sun, Chang-Zheng; Wang, Jian; Han, Yan-Jun; Li, Hong-Tao; Wang, Lu; Wang, Wen-Xin; Chen, Hong

    2015-09-01

    The next generation infrared (IR) detection and imaging technology calls for very large-scale IR sensitive chips with non-compromised performance. IR up-converters based on mature III-V semiconductors are thought to be quite promising candidates. However, the up-converters and the corresponding up-conversion systems so far substantially fall behind traditional IR detectors in terms of device performance due to the more serious trade-off between responsivity and dark current. In this article, a cascade infrared up-converter (CIUP) is proposed. By employing cascade carrier transport, IR responsivity can be enhanced while dark current remains in fairly low level. For the fabricated 4-μm InGaAs/AlGaAs CIUP under 3.3 V at 78 K, the up-conversion efficiency of the system is 2.1 mW/W under 2.1 μW mid-infrared input. Both the up-converter and the up-conversion system are under background-limited infrared performance regime below 120 K. Taking shot noise as the main source of system noise, the CIUP system displays a higher detectivity than previous semiconductor up-converters at similar wavelengths, and thus possesses greater potential for future large-scale IR detection and imaging applications.

  2. [A method of temperature measurement for hot forging with surface oxide based on infrared spectroscopy].

    PubMed

    Zhang, Yu-cun; Qi, Yan-de; Fu, Xian-bin

    2012-05-01

    High temperature large forging is covered with a thick oxide during forging. It leads to a big measurement data error. In this paper, a method of measuring temperature based on infrared spectroscopy is presented. It can effectively eliminate the influence of surface oxide on the measurement of temperature. The method can measure the surface temperature and emissivity of the oxide directly using the infrared spectrum. The infrared spectrum is radiated from surface oxide of forging. Then it can derive the real temperature of hot forging covered with the oxide using the heat exchange equation. In order to greatly restrain interference spectroscopy through included in the received infrared radiation spectrum, three interference filter system was proposed, and a group of optimal gap parameter values using spectral simulation were obtained. The precision of temperature measurement was improved. The experimental results show that the method can accurately measure the surface temperature of high temperature forging covered with oxide. It meets the requirements of measurement accuracy, and the temperature measurement method is feasible according to the experiment result. PMID:22827063

  3. A robust infrared dim target detection method based on template filtering and saliency extraction

    NASA Astrophysics Data System (ADS)

    Wang, Wenguang; Li, Chenming; Shi, Jianing

    2015-11-01

    Dim target detection in infrared image with complex background and low signal-clutter ratio (SCR) is a significant and difficult task in the infrared target tracking system. A robust infrared dim target detection method based on template filtering and saliency extraction is proposed in this paper. The weighted gray map is obtained from the infrared image to highlight the target which is brighter than its neighbors and has weak correlation with its background. The target saliency map is then calculated by phase spectrum of Fourier Transform, so that the dim target detection could be converted to salient region extraction. The potential targets are finally extracted by combining the two maps. Moreover, position discrimination between targets in the two maps is used to exclude the false alarms and extract the targets. Experimental results on measured images indicate that our method is feasible, adaptable and robust in different backgrounds. The ROC (Receiver Operating Characteristic) curves obtained from the simulated images demonstrate the proposed method outperforms some existing typical methods in both detection rate and false alarm rate, for target detection with low SCR.

  4. Silicon based near infrared photodetector using self-assembled organic crystalline nano-pillars

    NASA Astrophysics Data System (ADS)

    Ajiki, Yoshiharu; Kan, Tetsuo; Yahiro, Masayuki; Hamada, Akiko; Adachi, Junji; Adachi, Chihaya; Matsumoto, Kiyoshi; Shimoyama, Isao

    2016-04-01

    We propose a silicon (Si) based near-infrared photodetector using self-assembled organic crystalline nano-pillars, which were formed on an n-type Si substrate and were covered with an Au thin-film. These structures act as antennas for near-infrared light, resulting in an enhancement of the light absorption on the Au film. Because the Schottky junction is formed between the Au/n-type Si, the electron excited by the absorbed light can be detected as photocurrent. The optical measurement revealed that the nano-pillar structures enhanced the responsivity for the near-infrared light by 89 (14.5 mA/W) and 16 (0.433 mA/W) times compared with those of the photodetector without nano-pillars at the wavelengths of 1.2 and 1.3 μm, respectively. Moreover, no polarization dependency of the responsivity was observed, and the acceptable incident angle ranged from 0° to 30°. These broad responses were likely to be due to the organic nano-pillar structures' having variation in their orientation, which is advantageous for near-infrared detector uses.

  5. The infrared target enhancement method based on optimization at the whole directional polarization

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Li, Ji-Cheng; Wang, Sha-fei; Gong, Ting

    2016-03-01

    An infrared target enhancement method based on optimization in the whole directional polarization is studied in this paper. By using the description relationship between the stokes vector of incident light and the intensity of emergent light, the analytical formula between the intensity of emergent light and the polarizing angle is deduced, and thus virtually derives the intensity of emergent light from 0°to 360° polarizing angle. Then according to the criterion of maximum contrast between target and background, the searching of optimal polarizing angle is iteratively realized, and finally gets the enhanced infrared target image. The feasibility and validity of the algorithm are validated by using real long wave infrared (LWIR) polarization images of target. Experimental results show that, the enhanced image using proposed algorithm possesses obvious suppression effect of background clutter, and the quantitative evaluation under two kinds of image quality evaluation indexes of average gradient and image entropy also validates the effectiveness of our algorithm in infrared target enhancement.

  6. New method for moving objects segmentation based on human vision perception in infrared video

    NASA Astrophysics Data System (ADS)

    Min, Chaobo

    2013-07-01

    A new method for moving object segmentation based on human vision perception in infrared video is proposed. In this paper, we introduce a new region growing method to achieve the accurate and complete segmentation of the moving objects. At first, the ideal seeds of every moving object are extracted based on the "hole" effect of temporal difference, respectively. At the next step, on the basis of the consideration that human vision system (HVS) is most sensitive to the local contrast between targets and surrounding, we proposed a metric for "good" infrared target segmentation based on human vision perception. And according to this metric, a search method based on fine and rough adjustment is applied to determine the best growing threshold for every moving object. The segmented mask of every moving object is grown from the relevant seeds with the best growing threshold. At last, the segmented masks of all moving objects are merged into a complete segmented mask. Experimental results show that the proposed method is superior and effective on segmentation of moving object in infrared video.

  7. Femtosecond photoelectron point projection microscope

    SciTech Connect

    Quinonez, Erik; Handali, Jonathan; Barwick, Brett

    2013-10-15

    By utilizing a nanometer ultrafast electron source in a point projection microscope we demonstrate that images of nanoparticles with spatial resolutions of the order of 100 nanometers can be obtained. The duration of the emission process of the photoemitted electrons used to make images is shown to be of the order of 100 fs using an autocorrelation technique. The compact geometry of this photoelectron point projection microscope does not preclude its use as a simple ultrafast electron microscope, and we use simple analytic models to estimate temporal resolutions that can be expected when using it as a pump-probe ultrafast electron microscope. These models show a significant increase in temporal resolution when comparing to ultrafast electron microscopes based on conventional designs. We also model the microscopes spectroscopic abilities to capture ultrafast phenomena such as the photon induced near field effect.

  8. Irradiance-based emissivity correction in infrared thermography for electronic applications.

    PubMed

    Vellvehi, M; Perpiñà, X; Lauro, G L; Perillo, F; Jordà, X

    2011-11-01

    This work analyzes, discusses, and proposes a solution to the problem of the emissivity correction present in infrared thermography when coatings with known emissivity cannot be deposited on the inspected surface. It is shown that the conventional technique based on two reference thermal images and the linearization of the blackbody radiation dependence on temperature is not a reliable and accurate solution when compared with the coating procedure. In this scenario, a new approach based on the direct processing of the output signal of the infrared camera (which is proportional to the detected irradiance) is proposed to obtain an accurate emissivity and surrounding reflections map, perfectly compensating the thermal maps. The results obtained have been validated using a module as a test vehicle containing two thermal test chips which incorporate embedded temperature sensors. PMID:22128998

  9. Irradiance-based emissivity correction in infrared thermography for electronic applications

    NASA Astrophysics Data System (ADS)

    Vellvehi, M.; Perpiñà, X.; Lauro, G. L.; Perillo, F.; Jordà, X.

    2011-11-01

    This work analyzes, discusses, and proposes a solution to the problem of the emissivity correction present in infrared thermography when coatings with known emissivity cannot be deposited on the inspected surface. It is shown that the conventional technique based on two reference thermal images and the linearization of the blackbody radiation dependence on temperature is not a reliable and accurate solution when compared with the coating procedure. In this scenario, a new approach based on the direct processing of the output signal of the infrared camera (which is proportional to the detected irradiance) is proposed to obtain an accurate emissivity and surrounding reflections map, perfectly compensating the thermal maps. The results obtained have been validated using a module as a test vehicle containing two thermal test chips which incorporate embedded temperature sensors.

  10. Low Size, Weight and Power Concept for Mid-Wave Infrared Optical Communication Transceivers Based on Quantum Cascade Lasers

    NASA Technical Reports Server (NTRS)

    Luzhanskiy, Edward; Choa, Fow-Sen; Merritt, Scott; Yu, Anthony; Krainak, Michael

    2015-01-01

    The low complexity, low size, weight and power Mid-Wavelength Infra-Red optical communications transceiver concept presented, realized and tested in the laboratory environment. Resilience to atmospheric impairments analyzed with simulated turbulence. Performance compared to typical telecom based Short Wavelength Infra-Red transceiver.

  11. A cyanobenzo[a]phenoxazine-based near infrared lysosome-tracker for in cellulo imaging.

    PubMed

    Sun, Ru; Liu, Wu; Xu, Yu-Jie; Lu, Jian-Mei; Ge, Jian-Feng; Ihara, Masataka

    2013-11-25

    A cyanobenzo[a]phenoxazine-based pH probe with pKa = 5.0 exhibits OFF-ON emission at 625-850 nm upon excitation at 600 nm in aqueous buffers. The in cellulo imaging experiments with HeLa cells indicate that the probe can serve as a lysosome-specific probe under red light excitation (633 nm) with near infrared emission (650-790 nm). PMID:24100849

  12. Infrared systems design from an operational requirement using a hypercard-based program

    NASA Astrophysics Data System (ADS)

    Harris, William R.

    1991-09-01

    A HyperCard-based program, 'IR Assist,' takes the user through the logical steps in designing an imaging infrared (IIR) seeker concept. These steps progress from the postulated target characteristics, to the detector element size, to the errors encountered during missile flight. The IR Assist program was designed for simple database management, common 'what if' calculations, and 'what must be studied in order to complete' questions regarding an IIR seeker concept.

  13. Remote infrared chemical sensing using highly durable AlF(3)-based glass fibers.

    PubMed

    Iqbal, T; Shahriari, M R; Ulbrich, R; Sigel, G H

    1991-10-15

    Unclad, low-loss AlF(3)-based glass fibers with enhanced chemical durability have been successfully used for the first time to our knowledge as intrinsic evanescent infrared sensors for monitoring liquid chemicals. Different liquids with absorption bands between 1 and 4.5 microm, such as alcohol, acetonitrile, and mixtures of alcohol/acetonitrile and water/acetonitrile, have been tested. These fibers have also been used successfully as distributed sensors for simultaneous monitoring of different chemical species. PMID:19777048

  14. Fiber based infrared lasers and their applications in medicine, spectroscopy and metrology

    NASA Astrophysics Data System (ADS)

    Alexander, Vinay Varkey

    In my thesis, I have demonstrated the development of fiber based infrared lasers and devices for applications in medicine, spectroscopy and metrology. One of the key accomplishments presented in this thesis for medical applications is the demonstration of a focused infrared laser to perform renal denervation both in vivo and in vitro. Hypertension is a significant health hazard in the US and throughout the world, and the laser based renal denervation procedure may be a potential treatment for resistant hypertension. Compared to current treatment modalities, lasers may be able to perform treatments with lesser collateral tissue damage and quicker treatment times helping to reduce patient discomfort and pain. An additional medical application demonstrated in this thesis is the use of infrared fiber lasers to damage sebaceous glands in human skin as a potential treatment for acne. Another significant work presented in this thesis is a field trial performed at the Wright Patterson Air Force Base using a Short Wave Infrared (SWIR) Supercontinuum (SC) laser as an active illumination source for long distance reflectance measurements. In this case, an SC laser developed as part of this thesis is kept on a 12 story tower and propagated through the atmosphere to a target kept 1.6 km away and used to perform spectroscopy measurements. In the future this technology may permit 24/7 surveillance based on looking for the spectral signatures of materials. Beyond applications in defense, this technology may have far reaching commercial applications as well, including areas such as oil and natural resources exploration. Beyond these major contributions to the state-of-the-art, this thesis also describes other significant studies such as power scalability of SWIR SC sources and non-invasive measurement of surface roughness.

  15. Benzodipyrrole-based Donor-Acceptor-type Boron Complexes as Tunable Near-infrared-Absorbing Materials.

    PubMed

    Nakamura, Tomoya; Furukawa, Shunsuke; Nakamura, Eiichi

    2016-07-20

    Benzodipyrrole-based donor-acceptor boron complexes were designed and synthesized as near-infrared-absorbing materials. The electron-rich organic framework combined with the Lewis acidic boron co-ordination enabled us to tune the LUMO energy level and the HOMO-LUMO gap (i.e.,the absorption wavelength) by changing the organic acceptor units, the number of boron atoms, and the substituents on the boron atoms. PMID:27311060

  16. Infrared small target detection via line-based reconstruction and entropy-induced suppression

    NASA Astrophysics Data System (ADS)

    Shang, Ke; Sun, Xiao; Tian, Jinwen; Li, Yansheng; Ma, Jiayi

    2016-05-01

    This paper proposes a novel infrared small target detection method which is composed of two stages. The first stage is implemented by line-based reconstruction for suppressing the background clutter, and the second stage is induced by information entropy for further standing out the targets. Compared with the state-of-the-art approaches, the proposed approach is able to achieve better performance in terms of efficiency and accuracy.

  17. Electron tomography of HEK293T cells using scanning electron microscope-based scanning transmission electron microscopy.

    PubMed

    You, Yun-Wen; Chang, Hsun-Yun; Liao, Hua-Yang; Kao, Wei-Lun; Yen, Guo-Ji; Chang, Chi-Jen; Tsai, Meng-Hung; Shyue, Jing-Jong

    2012-10-01

    Based on a scanning electron microscope operated at 30 kV with a homemade specimen holder and a multiangle solid-state detector behind the sample, low-kV scanning transmission electron microscopy (STEM) is presented with subsequent electron tomography for three-dimensional (3D) volume structure. Because of the low acceleration voltage, the stronger electron-atom scattering leads to a stronger contrast in the resulting image than standard TEM, especially for light elements. Furthermore, the low-kV STEM yields less radiation damage to the specimen, hence the structure can be preserved. In this work, two-dimensional STEM images of a 1-μm-thick cell section with projection angles between ±50° were collected, and the 3D volume structure was reconstructed using the simultaneous iterative reconstructive technique algorithm with the TomoJ plugin for ImageJ, which are both public domain software. Furthermore, the cross-sectional structure was obtained with the Volume Viewer plugin in ImageJ. Although the tilting angle is constrained and limits the resulting structural resolution, slicing the reconstructed volume generated the depth profile of the thick specimen with sufficient resolution to examine cellular uptake of Au nanoparticles, and the final position of these nanoparticles inside the cell was imaged. PMID:23026379

  18. Measurement of the unstained biological sample by a novel scanning electron generation X-ray microscope based on SEM

    SciTech Connect

    Ogura, Toshihiko

    2009-08-07

    We introduced a novel X-ray microscope system based on scanning electron microscopy using thin film, which enables the measurement of unstained biological samples without damage. An unstained yeast sample was adsorbed under a titanium (Ti)-coated silicon nitride (Si{sub 3}N{sub 4}) film 90 nm thick. The X-ray signal from the film was detected by an X-ray photodiode (PD) placed below the sample. With an electron beam at 2.6 kV acceleration and 6.75 nA current, the yeast image is obtained using the X-ray PD. The image is created by soft X-rays from the Ti layer. The Ti layer is effective in generating the characteristic 2.7-nm wavelength X-rays by the irradiation of electrons. Furthermore, we investigated the electron trajectory and the generation of the characteristic X-rays within the Ti-coated Si{sub 3}N{sub 4} film by Monte Carlo simulation. Our system can be easily utilized to observe various unstained biological samples of cells, bacteria, and viruses.

  19. Determination of sulfadiazine based on its derivatization with fluorescamine by self-ordered ring fluorescence microscopic imaging technique.

    PubMed

    Yang, Le; Liu, Ying

    2012-09-01

    A self-ordered ring (SOR) fluorescence microscopic imaging technique has been developed for the determination of trace amounts of sulfadiazine based on its derivatization with fluorescamine. In the presence of HAc-NaAc buffer solution (pH 3.12) and polyvinyl alcohol-124 (PVA-124), the droplet containing fluorescamine derivatized sulfadiazine can form a SOR on the solid support after solvent evaporation with the diameter of 1.86 mm and its ring belt width of 54.9 microm. The quantitative analysis of sulfadiazine is achieved with the linear range of 7.8 x 10(-14)-1.8 x 10(-12) mol x ring(-1) (3.9 x 10(-7)-9.0 x 10(-6) mol x L(-1) and detection limit of 7.8 x 10(-5) mol x ring(-1) (3.9 x 10(-8) mol x L(-1)) when 0.2 microL droplet was spotted. The technique has been satisfactorily applied to the determination of sulfadiazine in the tablet, synthetic sample and residues in six different milk samples with the recoveries of 91.0%-105.8%, respectively, and RSDs less than 4.4%. PMID:23240417

  20. Piezoelectric bimorph-based scanner in the tip-scan mode for high speed atomic force microscope

    NASA Astrophysics Data System (ADS)

    Zhao, Jianyong; Gong, Weitao; Cai, Wei; Shang, Guangyi

    2013-08-01

    A piezoelectric bimorph-based scanner operating in tip-scan mode for high speed atomic force microscope (AFM) is first presented. The free end of the bimorph is used for fixing an AFM cantilever probe and the other one is mounted on the AFM head. The sample is placed on the top of a piezoelectric tube scanner. High speed scan is performed with the bimorph that vibrates at the resonant frequency, while slow scanning is carried out by the tube scanner. The design and performance of the scanner is discussed and given in detailed. Combined with a commercially available data acquisition system, a high speed AFM has been built successfully. By real-time observing the deformation of the pores on the surface of a commercial piezoelectric lead zirconate titanate (PZT-5) ceramics under electric field, the dynamic imaging capability of the AFM is demonstrated. The results show that the notable advantage of the AFM is that dynamic process of the sample with large dimensions can be easily investigated. In addition, this design could provide a way to study a sample in real time under the given experimental condition, such as under an external electric field, on a heating stage, or in a liquid cell.

  1. Piezoelectric bimorph-based scanner in the tip-scan mode for high speed atomic force microscope.

    PubMed

    Zhao, Jianyong; Gong, Weitao; Cai, Wei; Shang, Guangyi

    2013-08-01

    A piezoelectric bimorph-based scanner operating in tip-scan mode for high speed atomic force microscope (AFM) is first presented. The free end of the bimorph is used for fixing an AFM cantilever probe and the other one is mounted on the AFM head. The sample is placed on the top of a piezoelectric tube scanner. High speed scan is performed with the bimorph that vibrates at the resonant frequency, while slow scanning is carried out by the tube scanner. The design and performance of the scanner is discussed and given in detailed. Combined with a commercially available data acquisition system, a high speed AFM has been built successfully. By real-time observing the deformation of the pores on the surface of a commercial piezoelectric lead zirconate titanate (PZT-5) ceramics under electric field, the dynamic imaging capability of the AFM is demonstrated. The results show that the notable advantage of the AFM is that dynamic process of the sample with large dimensions can be easily investigated. In addition, this design could provide a way to study a sample in real time under the given experimental condition, such as under an external electric field, on a heating stage, or in a liquid cell. PMID:24007072

  2. A tuning fork based wide range mechanical characterization tool with nanorobotic manipulators inside a scanning electron microscope.

    PubMed

    Acosta, Juan Camilo; Hwang, Gilgueng; Polesel-Maris, Jérôme; Régnier, Stéphane

    2011-03-01

    This study proposes a tuning fork probe based nanomanipulation robotic system for mechanical characterization of ultraflexible nanostructures under scanning electron microscope. The force gradient is measured via the frequency modulation of a quartz tuning fork and two nanomanipulators are used for manipulation of the nanostructures. Two techniques are proposed for attaching the nanostructure to the tip of the tuning fork probe. The first technique involves gluing the nanostructure for full range characterization whereas the second technique uses van der Waals and electrostatic forces in order to avoid destroying the nanostructure. Helical nanobelts (HNB) are proposed for the demonstration of the setup. The nonlinear stiffness behavior of HNBs during their full range tensile studies is clearly revealed for the first time. Using the first technique, this was between 0.009 N/m for rest position and 0.297 N/m before breaking of the HNB with a resolution of 0.0031 N/m. For the second experiment, this was between 0.014 N/m for rest position and 0.378 N/m before detaching of the HNB with a resolution of 0.0006 N/m. This shows the wide range sensing of the system for potential applications in mechanical property characterization of ultraflexible nanostructures. PMID:21456797

  3. A tuning fork based wide range mechanical characterization tool with nanorobotic manipulators inside a scanning electron microscope

    SciTech Connect

    Acosta, Juan Camilo; Hwang, Gilgueng; Regnier, Stephane; Polesel-Maris, Jerome

    2011-03-15

    This study proposes a tuning fork probe based nanomanipulation robotic system for mechanical characterization of ultraflexible nanostructures under scanning electron microscope. The force gradient is measured via the frequency modulation of a quartz tuning fork and two nanomanipulators are used for manipulation of the nanostructures. Two techniques are proposed for attaching the nanostructure to the tip of the tuning fork probe. The first technique involves gluing the nanostructure for full range characterization whereas the second technique uses van der Waals and electrostatic forces in order to avoid destroying the nanostructure. Helical nanobelts (HNB) are proposed for the demonstration of the setup. The nonlinear stiffness behavior of HNBs during their full range tensile studies is clearly revealed for the first time. Using the first technique, this was between 0.009 N/m for rest position and 0.297 N/m before breaking of the HNB with a resolution of 0.0031 N/m. For the second experiment, this was between 0.014 N/m for rest position and 0.378 N/m before detaching of the HNB with a resolution of 0.0006 N/m. This shows the wide range sensing of the system for potential applications in mechanical property characterization of ultraflexible nanostructures.

  4. Theoretical investigation of all-metal-based mushroom plasmonic metamaterial absorbers at infrared wavelengths

    NASA Astrophysics Data System (ADS)

    Ogawa, Shinpei; Fujisawa, Daisuke; Kimata, Masafumi

    2015-12-01

    High-performance wavelength-selective infrared (IR) sensors require small pixel structures, a low-thermal mass, and operation in the middle-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) regions for multicolor IR imaging. All-metal-based mushroom plasmonic metamaterial absorbers (MPMAs) were investigated theoretically and were designed to enhance the performance of wavelength-selective uncooled IR sensors. All components of the MPMAs are based on thin layers of metals such as Au without oxide insulators for increased absorption. The absorption properties of the MPMAs were investigated by rigorous coupled-wave analysis. Strong wavelength-selective absorption is realized over a wide range of MWIR and LWIR wavelengths by the plasmonic resonance of the micropatch and the narrow-gap resonance, without disturbance from the intrinsic absorption of oxide insulators. The absorption wavelength is defined mainly by the micropatch size and is longer than its period. The metal post width has less impact on the absorption properties and can maintain single-mode operation. Through-holes can be formed on the plate area to reduce the thermal mass. A small pixel size with reduced thermal mass and wideband single-mode operation can be realized using all-metal-based MPMAs.

  5. Design of infrared signal processing system based on heterogeneous MPSoC

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Tang, Xinyi

    2015-02-01

    As one of the most significant parts in the development of the next generation infrared detection system, the infrared signal processing system requires the ability of real-time processing and high speed data transmission. A newly developed real-time signal processing system for infrared detecting based on the heterogeneous multiprocessor system on chip (MPSoC) is proposed in this paper. The device follows the architecture of Xilinx Zynq platform, integrating a feature rich dual-core ARM and Xilinx FPGA in a single chip, built on the 28nm high-k metal gate process technology. According to our design, the FPGA fabric portion retains all the programmable flexibility to drive the infrared detector and acquire data from ADC, with registers parallel operations to implement hardware acceleration. Furthermore, the FPGA fabric is connected to the ARM centered processor unit through multiple high performance interfaces, confirming high bandwidth communication and high speed data transmission between the two portions. Finally, the dual core ARM takes charge of the infrared signal processing system in general. One of the CPUs controls separate hardware modules and maintains the GUI for user interaction. The other responds to the dedicated system commands and external interrupts to update system parameters simultaneously. The integration of ARM and FPGA provides levels of performance that two-chip solutions cannot match due to their limited I/O bandwidth, loose coupling and power budgets. Experiments show that the architecture of heterogeneous MPSoC enhances the efficiency of memory controller and increases the speed of data transmission, approaching the theoretical value of the interfaces bandwidth.

  6. The ship-borne infrared searching and tracking system based on the inertial platform

    NASA Astrophysics Data System (ADS)

    Li, Yan; Zhang, Haibo

    2011-08-01

    As a result of the radar system got interferenced or in the state of half silent ,it can cause the guided precision drop badly In the modern electronic warfare, therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings, but when interference is in the process of radar leading ,especially the electro-optical equipment is influenced by the roll, pitch and yaw rotation ,it can affect the target appear outside of the field of optoelectronic devices for a long time, so the infrared optoelectronic equipment can not exert the superiority, and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly , the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene, the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing

  7. Development of plenoptic infrared camera using low dimensional material based photodetectors

    NASA Astrophysics Data System (ADS)

    Chen, Liangliang

    Infrared (IR) sensor has extended imaging from submicron visible spectrum to tens of microns wavelength, which has been widely used for military and civilian application. The conventional bulk semiconductor materials based IR cameras suffer from low frame rate, low resolution, temperature dependent and highly cost, while the unusual Carbon Nanotube (CNT), low dimensional material based nanotechnology has been made much progress in research and industry. The unique properties of CNT lead to investigate CNT based IR photodetectors and imaging system, resolving the sensitivity, speed and cooling difficulties in state of the art IR imagings. The reliability and stability is critical to the transition from nano science to nano engineering especially for infrared sensing. It is not only for the fundamental understanding of CNT photoresponse induced processes, but also for the development of a novel infrared sensitive material with unique optical and electrical features. In the proposed research, the sandwich-structured sensor was fabricated within two polymer layers. The substrate polyimide provided sensor with isolation to background noise, and top parylene packing blocked humid environmental factors. At the same time, the fabrication process was optimized by real time electrical detection dielectrophoresis and multiple annealing to improve fabrication yield and sensor performance. The nanoscale infrared photodetector was characterized by digital microscopy and precise linear stage in order for fully understanding it. Besides, the low noise, high gain readout system was designed together with CNT photodetector to make the nano sensor IR camera available. To explore more of infrared light, we employ compressive sensing algorithm into light field sampling, 3-D camera and compressive video sensing. The redundant of whole light field, including angular images for light field, binocular images for 3-D camera and temporal information of video streams, are extracted and

  8. Efficient Selection and Classification of Infrared Excess Emission Stars Based on AKARI and 2MASS Data

    NASA Astrophysics Data System (ADS)

    Li, Jinzeng; Huang, Yafang

    2015-08-01

    The selection of young stellar objects (YSOs) based on excessive emission in the infrared is easily contaminated by post-main-sequence stars and various types of emission line stars with similar properties. We define here stringent criteria for an efficient selection and classification of stellar sources with infrared excess emission based on combined 2MASS and AKARI colors. First of all, bright dwarfs and giants with known spectral types were selected from the Hipparcos Catalogue and cross-identified with the 2MASS and AKARI Point Source Catalogues to produce the main-sequence and the post-main-sequence tracks, which appear as expected as tight tracks with very small dispersion. However, several of the main-sequence stars indicate excess emission in the color space. Further investigations based on the SIMBAD data help to clarify their nature as classical Be stars, which are found to be located in a well isolated region on each of the color-color (C-C) diagrams. Several kinds of contaminants were then removed based on their distribution on the C-C diagrams. A test sample of Herbig Ae/Be stars and classical T Tauri stars were cross-identified with the 2MASS and AKARI catalogs to define the loci of YSOs with different masses on the C-C diagrams. Well classified Class I and Class II sources were taken as a second test sample to discriminate between various types of YSOs at possibly different evolutionary stages. This helped to define the loci of different types of YSOs and a set of criteria for selecting YSOs based on their colors in the near- and mid-infrared. Candidate YSOs toward IC 1396 indicating excess emission in the near-infrared were employed to verify the validity of the new source selection criteria defined based on C-C diagrams compiled with the 2MASS and AKARI data. Optical spectroscopy and spectral energy distributions of the IC 1396 sample yield a clear identification of the YSOs and further confirm the criteria defined for exploring the nature and

  9. Efficient Selection and Classification of Infrared Excess Emission Stars Based on AKARI and 2MASS Data

    NASA Astrophysics Data System (ADS)

    Huang, Ya Fang; Zeng Li, Jin; Rector, Travis A.; Mallamaci, Carlos C.

    2013-05-01

    The selection of young stellar objects (YSOs) based on excess emission in the infrared is easily contaminated by post-main-sequence stars and various types of emission line stars with similar properties. We define in this paper stringent criteria for an efficient selection and classification of stellar sources with infrared excess emission based on combined Two Micron All Sky Survey (2MASS) and AKARI colors. First of all, bright dwarfs and giants with known spectral types were selected from the Hipparcos Catalogue and cross-identified with the 2MASS and AKARI Point Source Catalogues to produce the main-sequence and the post-main-sequence tracks, which appear as expected as tight tracks with very small dispersion. However, several of the main-sequence stars indicate excess emission in the color space. Further investigations based on the SIMBAD data help to clarify their nature as classical Be stars, which are found to be located in a well isolated region on each of the color-color (C-C) diagrams. Several kinds of contaminants were then removed based on their distribution in the C-C diagrams. A test sample of Herbig Ae/Be stars and classical T Tauri stars were cross-identified with the 2MASS and AKARI catalogs to define the loci of YSOs with different masses on the C-C diagrams. Well classified Class I and Class II sources were taken as a second test sample to discriminate between various types of YSOs at possibly different evolutionary stages. This helped to define the loci of different types of YSOs and a set of criteria for selecting YSOs based on their colors in the near- and mid-infrared. Candidate YSOs toward IC 1396 indicating excess emission in the near-infrared were employed to verify the validity of the new source selection criteria defined based on C-C diagrams compiled with the 2MASS and AKARI data. Optical spectroscopy and spectral energy distributions of the IC 1396 sample yield a clear identification of the YSOs and further confirm the criteria defined

  10. EFFICIENT SELECTION AND CLASSIFICATION OF INFRARED EXCESS EMISSION STARS BASED ON AKARI AND 2MASS DATA

    SciTech Connect

    Huang Yafang; Li Jinzeng; Rector, Travis A.; Mallamaci, Carlos C.

    2013-05-15

    The selection of young stellar objects (YSOs) based on excess emission in the infrared is easily contaminated by post-main-sequence stars and various types of emission line stars with similar properties. We define in this paper stringent criteria for an efficient selection and classification of stellar sources with infrared excess emission based on combined Two Micron All Sky Survey (2MASS) and AKARI colors. First of all, bright dwarfs and giants with known spectral types were selected from the Hipparcos Catalogue and cross-identified with the 2MASS and AKARI Point Source Catalogues to produce the main-sequence and the post-main-sequence tracks, which appear as expected as tight tracks with very small dispersion. However, several of the main-sequence stars indicate excess emission in the color space. Further investigations based on the SIMBAD data help to clarify their nature as classical Be stars, which are found to be located in a well isolated region on each of the color-color (C-C) diagrams. Several kinds of contaminants were then removed based on their distribution in the C-C diagrams. A test sample of Herbig Ae/Be stars and classical T Tauri stars were cross-identified with the 2MASS and AKARI catalogs to define the loci of YSOs with different masses on the C-C diagrams. Well classified Class I and Class II sources were taken as a second test sample to discriminate between various types of YSOs at possibly different evolutionary stages. This helped to define the loci of different types of YSOs and a set of criteria for selecting YSOs based on their colors in the near- and mid-infrared. Candidate YSOs toward IC 1396 indicating excess emission in the near-infrared were employed to verify the validity of the new source selection criteria defined based on C-C diagrams compiled with the 2MASS and AKARI data. Optical spectroscopy and spectral energy distributions of the IC 1396 sample yield a clear identification of the YSOs and further confirm the criteria defined

  11. Division of focal plane polarimeter-based 3 × 4 Mueller matrix microscope: a potential tool for quick diagnosis of human carcinoma tissues

    NASA Astrophysics Data System (ADS)

    Chang, Jintao; He, Honghui; Wang, Ye; Huang, Yi; Li, Xianpeng; He, Chao; Liao, Ran; Zeng, Nan; Liu, Shaoxiong; Ma, Hui

    2016-05-01

    A polarization microscope is a useful tool to reveal the optical anisotropic nature of a specimen and can provide abundant microstructural information about samples. We present a division of focal plane (DoFP) polarimeter-based polarization microscope capable of simultaneously measuring both the Stokes vector and the 3×4 Mueller matrix with an optimal polarization illumination scheme. The Mueller matrix images of unstained human carcinoma tissue slices show that the m24 and m34 elements can provide important information for pathological observations. The characteristic features of the m24 and m34 elements can be enhanced by polarization staining under illumination by a circularly polarized light. Hence, combined with a graphics processing unit acceleration algorithm, the DoFP polarization microscope is capable of real-time polarization imaging for potential quick clinical diagnoses of both standard and frozen slices of human carcinoma tissues.

  12. An improvement for scene-based nonuniformity correction of infrared image sequences

    NASA Astrophysics Data System (ADS)

    Geng, Lixiang; Chen, Qian; Shi, Feng; Wang, Changjiang; Yu, Xuelian

    2013-09-01

    Scene-based nonuniformity correction technique for Infrared focal-plane array has been widely concerned as a key technology. However, the existed algorithms are now facing two major problems that is convergence speed and ghosting artifacts. The convergence speed of original constant statistics (CS) method has been demonstrated to be more rapidly than the neural network method but how to reduce ghosting artifacts efficiently is the largest challenge. To solve the ghosting problem, the conventional methods often set a threshold to wipe off the outliers, but the threshold is difficult to choose because it changes complexly for different scene. In this paper, a novel adaptive scene-based nonuniformity correction technique is presented that performs the nonuniformity correction based on CS method. Firstly, an analysis of statistical characteristic in every pixel is taken and the cause of ghosting artifacts is discussed that the underlying distribution does not satisfy the assumptions such as symmetry. For the Gaussian distribution can not describe the statistic property for every pixel's data, a model with mixture distribution is constructed and indicates the different distribution's influence to generate ghosting artifacts. Then, utilizing temporal statistics of infrared image sequences the proposed method applies an alpha-trimmed mean filter to estimate detector parameters instead of the conventional mean filter. The algorithm selects the parameter of the alpha-trimmed mean estimator optimally with minimizing the sample asymptotic variance estimate. Moreover, the alpha-trimmed mean filter is designed to detect the nonsymmetry points and trim out the outlier pixels such as edges or extreme distribution. Finally, the performance of the proposed algorithm is evaluated with infrared image sequences with simulated and real fixed-pattern noise. Compared with other nonuniformity correction techniques, the proposed method inherits the superiority of the CS method that

  13. Near-infrared Thermal Emission Detections of a Number of Hot Jupiters and the Systematics of Ground-based Near-infrared Photometry

    NASA Astrophysics Data System (ADS)

    Croll, Bryce; Albert, Loic; Jayawardhana, Ray; Cushing, Michael; Moutou, Claire; Lafreniere, David; Johnson, John Asher; Bonomo, Aldo S.; Deleuil, Magali; Fortney, Jonathan

    2015-03-01

    We present detections of the near-infrared thermal emission of three hot Jupiters and one brown dwarf using the Wide-field Infrared Camera (WIRCam) on the Canada-France-Hawaii Telescope (CFHT). These include Ks-band secondary eclipse detections of the hot Jupiters WASP-3b and Qatar-1b and the brown dwarf KELT-1b. We also report Y-band, K CONT-band, and two new and one reanalyzed Ks-band detections of the thermal emission of the hot Jupiter WASP-12b. We present a new reduction pipeline for CFHT/WIRCam data, which is optimized for high precision photometry. We also describe novel techniques for constraining systematic errors in ground-based near-infrared photometry, so as to return reliable secondary eclipse depths and uncertainties. We discuss the noise properties of our ground-based photometry for wavelengths spanning the near-infrared (the YJHK bands), for faint and bright stars, and for the same object on several occasions. For the hot Jupiters WASP-3b and WASP-12b we demonstrate the repeatability of our eclipse depth measurements in the Ks band; we therefore place stringent limits on the systematics of ground-based, near-infrared photometry, and also rule out violent weather changes in the deep, high pressure atmospheres of these two hot Jupiters at the epochs of our observations. Based on observations obtained with WIRCam, a joint project of Canada-France-Hawaii Telescope (CFHT), Taiwan, Korea, Canada, France, at the CFHT, which is operated by the National Research Council (NRC) of Canada, the Institute National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

  14. A Review of Automatic Methods Based on Image Processing Techniques for Tuberculosis Detection from Microscopic Sputum Smear Images.

    PubMed

    Panicker, Rani Oomman; Soman, Biju; Saini, Gagan; Rajan, Jeny

    2016-01-01

    Tuberculosis (TB) is an infectious disease caused by the bacteria Mycobacterium tuberculosis. It primarily affects the lungs, but it can also affect other parts of the body. TB remains one of the leading causes of death in developing countries, and its recent resurgences in both developed and developing countries warrant global attention. The number of deaths due to TB is very high (as per the WHO report, 1.5 million died in 2013), although most are preventable if diagnosed early and treated. There are many tools for TB detection, but the most widely used one is sputum smear microscopy. It is done manually and is often time consuming; a laboratory technician is expected to spend at least 15 min per slide, limiting the number of slides that can be screened. Many countries, including India, have a dearth of properly trained technicians, and they often fail to detect TB cases due to the stress of a heavy workload. Automatic methods are generally considered as a solution to this problem. Attempts have been made to develop automatic approaches to identify TB bacteria from microscopic sputum smear images. In this paper, we provide a review of automatic methods based on image processing techniques published between 1998 and 2014. The review shows that the accuracy of algorithms for the automatic detection of TB increased significantly over the years and gladly acknowledges that commercial products based on published works also started appearing in the market. This review could be useful to researchers and practitioners working in the field of TB automation, providing a comprehensive and accessible overview of methods of this field of research. PMID:26573654

  15. Mid-infrared frequency comb based on a quantum cascade laser.

    PubMed

    Hugi, Andreas; Villares, Gustavo; Blaser, Stéphane; Liu, H C; Faist, Jérôme

    2012-12-13

    Optical frequency combs act as rulers in the frequency domain and have opened new avenues in many fields such as fundamental time metrology, spectroscopy and frequency synthesis. In particular, spectroscopy by means of optical frequency combs has surpassed the precision and speed of Fourier spectrometers. Such a spectroscopy technique is especially relevant for the mid-infrared range, where the fundamental rotational-vibrational bands of most light molecules are found. Most mid-infrared comb sources are based on down-conversion of near-infrared, mode-locked, ultrafast lasers using nonlinear crystals. Their use in frequency comb spectroscopy applications has resulted in an unequalled combination of spectral coverage, resolution and sensitivity. Another means of comb generation is pumping an ultrahigh-quality factor microresonator with a continuous-wave laser. However, these combs depend on a chain of optical components, which limits their use. Therefore, to widen the spectroscopic applications of such mid-infrared combs, a more direct and compact generation scheme, using electrical injection, is preferable. Here we present a compact, broadband, semiconductor frequency comb generator that operates in the mid-infrared. We demonstrate that the modes of a continuous-wave, free-running, broadband quantum cascade laser are phase-locked. Combining mode proliferation based on four-wave mixing with gain provided by the quantum cascade laser leads to a phase relation similar to that of a frequency-modulated laser. The comb centre carrier wavelength is 7 micrometres. We identify a narrow drive current range with intermode beat linewidths narrower than 10 hertz. We find comb bandwidths of 4.4 per cent with an intermode stability of less than or equal to 200 hertz. The intermode beat can be varied over a frequency range of 65 kilohertz by radio-frequency injection. The large gain bandwidth and independent control over the carrier frequency offset and the mode spacing

  16. Micro-spectroscopy system based on common inverted microscope to measure UV-VIS spectra of a micro-area

    NASA Astrophysics Data System (ADS)

    Yang, Ailing; Zhang, Jinliang; Ren, Weiwei; Tang, Mingming

    2009-05-01

    For measuring UV-VIS spectra of a micro-area, an upright triocular UV microscope has to be generally used and reequipped by the user. This greatly increased the cost of the experimental system and might make the microscope lose the function of taking a photograph. In this paper, a new micro-spectroscopy system is established for measuring fluorescence of a micro-area. This system includes in a reflective microscope objective(RMO), a fiber cable, a microlens, a 3D adjustable fiber-microlens-microscope adaptor(FMMA), a fluorescence meter and a common inverted fluorescence microscope(IFM). The cheap and common IFM replaced an expensive UV upright microscope and no need to rebuild the microscope itself. Except for the FMMA, all the other elements are standard products. All elements are easily integrated into a whole, so the cost of the system is greatly decreased. The space resolution of this system is 2μm. This system can be used to localize a micro-area, excite it with a monochromatic light, take a photograph of it, collect wake fluorescence of it and measure its UV-VIS spectra. This system is stable and has a high sensitivity. It is promising to measure the fluorescence of a mineral grain, the organic matters in a micro-fracture, or a single fluid inclusion. Because it used an IFM, it can also to be used to the biology samples, such as cell or bio-inclusion. We used this system to measure the UVVIS spectrum of oils in a single micro-fracture of a mineral slice and the spectra of a single mineral grain in a mineral slice.

  17. [The correlation based mid-infrared temperature and emissivity separation algorithm].

    PubMed

    Cheng, Jie; Nie, Ai-Xiu; Du, Yong-Ming

    2009-02-01

    Temperature and emissivity separation is the key problem in infrared remote sensing. Based on the analysis of the relationship between the atmospheric downward radiance and surface emissivity containing atmosphere residue without the effects of sun irradiation, the present paper puts forward a temperature and emissivity separation algorithm for the ground-based mid-infrared hyperspectral data. The algorithm uses the correlation between the atmospheric downward radiance and surface emissivity containing atmosphere residue as a criterion to optimize the surface temperature, and the correlation between the atmospheric downward radiance and surface emissivity containing atmosphere residue depends on the bias between the estimated surface temperature and true surface temperature. The larger the temperature bias, the greater the correlation. Once we have obtained the surface temperature, the surface emissivity can be calculated easily. The accuracy of the algorithm was evaluated with the simulated mid-infrared hyperspectral data. The results of simulated calculation show that the algorithm can achieve higher accuracy of temperature and emissivity inversion, and also has broad applicability. Meanwhile, the algorithm is insensitive to the instrumental random noise and the change in atmospheric downward radiance during the field measurements. PMID:19445199

  18. A color fusion method of infrared and low-light-level images based on visual perception

    NASA Astrophysics Data System (ADS)

    Han, Jing; Yan, Minmin; Zhang, Yi; Bai, Lianfa

    2014-11-01

    The color fusion images can be obtained through the fusion of infrared and low-light-level images, which will contain both the information of the two. The fusion images can help observers to understand the multichannel images comprehensively. However, simple fusion may lose the target information due to inconspicuous targets in long-distance infrared and low-light-level images; and if targets extraction is adopted blindly, the perception of the scene information will be affected seriously. To solve this problem, a new fusion method based on visual perception is proposed in this paper. The extraction of the visual targets ("what" information) and parallel processing mechanism are applied in traditional color fusion methods. The infrared and low-light-level color fusion images are achieved based on efficient typical targets learning. Experimental results show the effectiveness of the proposed method. The fusion images achieved by our algorithm can not only improve the detection rate of targets, but also get rich natural information of the scenes.

  19. Continuous glucose determination using fiber-based tunable mid-infrared laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Yu, Songlin; Li, Dachao; Chong, Hao; Sun, Changyue; Xu, Kexin

    2014-04-01

    Wavelength-tunable laser spectroscopy in combination with a small-sized fiber-optic attenuated total reflection (ATR) sensor (fiber-based evanescent field analysis, FEFA) is reported for the continuous measurement of the glucose level. We propose a method of controlling and stabilizing the wavelength and power of laser emission and present a newly developed mid-infrared wavelength-tunable laser with a broad emission spectrum band of 9.19-9.77 μm (1024-1088 cm-1). The novel small-sized flow-through fiber-optic ATR sensor with long optical sensing length was used for glucose level determination. The experimental results indicate that the noise-equivalent concentration of this laser measurement system is as low as 3.8 mg/dL, which is among the most precise glucose measurements using mid-infrared spectroscopy. The sensitivity, which is three times that of conventional Fourier transform infrared spectrometer, was acquired because of the higher laser power and higher spectral resolution. The best prediction of the glucose concentration in phosphate buffered saline solution was achieved using the five-variable partial least-squares model, yielding a root-mean-square error of prediction as small as 3.5 mg/dL. The high sensitivity, multiple tunable wavelengths and small fiber-based sensor with long optical sensing length make glucose determination possible in blood or interstitial fluid in vivo.

  20. Complex morphology small targets detection based on spatial-temporal sparse recovery in infrared surveillance system

    NASA Astrophysics Data System (ADS)

    Li, Miao; Wang, Qi; Li, Jun; Long, Yunli; Zheng, Yu

    2016-01-01

    Complex morphology target, which is size-varying and shape-varying, is a great challenge for infrared surveillance system. In this paper, temporal low-rank and sparse decomposition model and spatial low-rank and sparse decomposition model are designed respectively. Subsequently, a joint spatial-temporal detection method of complex morphology target is presented. Firstly, initial background subspace is obtained based on training sequence which does not contain infrared target. Secondly, temporal target image is recovered by l1 minimization after projecting orthogonal to background subspace. Thirdly, original image is decomposed into background image and spatial target image using inexact augmented Lagrange multipliers approach. Fourthly, by fusing the two target images, the possible small targets can be extracted well. Finally, background subspace is updated based on incremental singular value decomposition algorithm. The experimental results show that our method is effective and robust to detect complex morphology infrared targets. In particular, the proposed method can extract targets accurately, which is important for target recognition.

  1. From selenium- to tellurium-based glass optical fibers for infrared spectroscopies.

    PubMed

    Cui, Shuo; Chahal, Radwan; Boussard-Plédel, Catherine; Nazabal, Virginie; Doualan, Jean-Louis; Troles, Johann; Lucas, Jacques; Bureau, Bruno

    2013-01-01

    Chalcogenide glasses are based on sulfur, selenium and tellurium elements, and have been studied for several decades regarding different applications. Among them, selenide glasses exhibit excellent infrared transmission in the 1 to 15 µm region. Due to their good thermo-mechanical properties, these glasses could be easily shaped into optical devices such as lenses and optical fibers. During the past decade of research, selenide glass fibers have been proved to be suitable for infrared sensing in an original spectroscopic method named Fiber Evanescent Wave Spectroscopy (FEWS). FEWS has provided very nice and promising results, for example for medical diagnosis. Then, some sophisticated fibers, also based on selenide glasses, were developed: rare-earth doped fibers and microstructured fibers. In parallel, the study of telluride glasses, which can have transmission up to 28 µm due to its atom heaviness, has been intensified thanks to the DARWIN mission led by the European Space Agency (ESA). The development of telluride glass fiber enables a successful observation of CO₂ absorption band located around 15 µm. In this paper we review recent results obtained in the Glass and Ceramics Laboratory at Rennes on the development of selenide to telluride glass optical fibers, and their use for spectroscopy from the mid to the far infrared ranges. PMID:23666005

  2. [Detection technology of methane gas concentration based on infrared absorption spectrum].

    PubMed

    Luo, Da-Feng; Yang, Jian-Hua; Zhong, Chong-Gui

    2011-02-01

    According to the disadvantages of current methane sensor in coal mine, the infrared methane concentration detection system based on the principle of infrared spectrum absorption was designed using differential absorption technology. In the system single light beam absorbing cell and single light beam and double wavelengths technology are adopted. Differential amplifier circuit serves as the core of faint signal processing circuit that detects the output signal of methane concentration, and linear formula fits the curve of methane concentration and output voltage, which realizes accurate and full range detection of gas concentration. Experiment shows that measurement error is less than 2%, and the system has very high measurement precision and possesses the basis of industrial applications. PMID:21510386

  3. Autonomous docking based on infrared system for electric vehicle charging in urban areas.

    PubMed

    Pérez, Joshué; Nashashibi, Fawzi; Lefaudeux, Benjamin; Resende, Paulo; Pollard, Evangeline

    2013-01-01

    Electric vehicles are progressively introduced in urban areas, because of their ability to reduce air pollution, fuel consumption and noise nuisance. Nowadays, some big cities are launching the first electric car-sharing projects to clear traffic jams and enhance urban mobility, as an alternative to the classic public transportation systems. However, there are still some problems to be solved related to energy storage, electric charging and autonomy. In this paper, we present an autonomous docking system for electric vehicles recharging based on an embarked infrared camera performing infrared beacons detection installed in the infrastructure. A visual servoing system coupled with an automatic controller allows the vehicle to dock accurately to the recharging booth in a street parking area. The results show good behavior of the implemented system, which is currently deployed as a real prototype system in the city of Paris. PMID:23429581

  4. Autonomous Docking Based on Infrared System for Electric Vehicle Charging in Urban Areas

    PubMed Central

    Pérez, Joshué; Nashashibi, Fawzi; Lefaudeux, Benjamin; Resende, Paulo; Pollard, Evangeline

    2013-01-01

    Electric vehicles are progressively introduced in urban areas, because of their ability to reduce air pollution, fuel consumption and noise nuisance. Nowadays, some big cities are launching the first electric car-sharing projects to clear traffic jams and enhance urban mobility, as an alternative to the classic public transportation systems. However, there are still some problems to be solved related to energy storage, electric charging and autonomy. In this paper, we present an autonomous docking system for electric vehicles recharging based on an embarked infrared camera performing infrared beacons detection installed in the infrastructure. A visual servoing system coupled with an automatic controller allows the vehicle to dock accurately to the recharging booth in a street parking area. The results show good behavior of the implemented system, which is currently deployed as a real prototype system in the city of Paris. PMID:23429581

  5. Calibration method for spectral responsivity of infrared detector based on blackbody at multiple temperature

    NASA Astrophysics Data System (ADS)

    Zhang, Y. F.; Shao, Z. F.; Wu, Y. Q.

    2015-08-01

    The spectral responsivity is one of the most important technical indicators of infrared detector which has an important significance for radiation thermometry and emissivity measurement. Using a blackbody radiation at multiple temperatures, the calibration for spectral responsivity of the infrared detector is proposed. With the Planck's law, the spectral radiance of blackbody at the different temperature is calculated. The detector captures the radiation and generates output values each of those is the function of spectral responsivity, spectral radiance and environmental radiation. Calibration equation is established by means of the calculated radiance and output values. By solving the equations based on principle of least squares, the calibration of spectral responsivity is implemented. From the comparison experiment of measuring the radiance of blackbody at 850K, radiance value measured by the MCT detector has a good consistency with the theoretical data.

  6. Cascade-coupled racetrack resonators based on the Vernier effect in the mid-infrared.

    PubMed

    Troia, Benedetto; Khokhar, Ali Z; Nedeljkovic, Milos; Penades, Jordi Soler; Passaro, Vittorio M N; Mashanovich, Goran Z

    2014-10-01

    In this paper we report the experimental demonstration of racetrack resonators in silicon-on-insulator technology platform operating in the mid-infrared wavelength range of 3.7-3.8 μm. Insertion loss lower than 1 dB and extinction ratio up to 30 dB were measured for single resonators. The experimental characterization of directional couplers and bending losses in silicon rib waveguides are also reported. Furthermore, we present the design and fabrication of cascade-coupled racetrack resonators based on the Vernier effect. Experimental spectra of Vernier architectures were demonstrated for the first time in the mid-infrared with insertion loss lower than 1 dB and maximum interstitial peak suppression of 10 dB. PMID:25321975

  7. Theoretical analysis and design of a near-infrared broadband absorber based on EC model.

    PubMed

    Zhang, Qing; Bai, Lihua; Bai, Zhengyuan; Hu, Pidong; Liu, Chengpu

    2015-04-01

    We theoretically introduced a design paradigm and tool by extending the circuit functionalities from radio frequency to near infrared domain, and its first usage to design a broadband near-infrared (1.5μm~3.5μm) absorber, is successfully demonstrated. After extracting the equivalent circuit (EC) model of the absorber structure, the formerly relatively complicated frequency response can be evaluated relatively easily based on classic circuit formulas. The feasibility is confirmed by its consistency with the rigorous FDTD calculation. The absorber is an array of truncated metal-dielectric multilayer composited pyramid unit structure, and the gradually modified square patch design makes the absorber be not sensitive to the incident angle and polarization of light. PMID:25968728

  8. Quantitative detection of defects based on Markov-PCA-BP algorithm using pulsed infrared thermography technology

    NASA Astrophysics Data System (ADS)

    Tang, Qingju; Dai, Jingmin; Liu, Junyan; Liu, Chunsheng; Liu, Yuanlin; Ren, Chunping

    2016-07-01

    Quantitative detection of debonding defects' diameter and depth in TBCs has been carried out using pulsed infrared thermography technology. By combining principal component analysis with neural network theory, the Markov-PCA-BP algorithm was proposed. The principle and realization process of the proposed algorithm was described. In the prediction model, the principal components which can reflect most characteristics of the thermal wave signal were set as the input, and the defect depth and diameter was set as the output. The experimental data from pulsed infrared thermography tests of TBCs with flat bottom hole defects was selected as the training and testing sample. Markov-PCA-BP predictive system was arrived, based on which both the defect depth and diameter were identified accurately, which proved the effectiveness of the proposed method for quantitative detection of debonding defects in TBCs.

  9. Near-Infrared Phosphorescent Iridium(III) Benzonorrole Complexes Possessing Pyridine-based Axial Ligands.

    PubMed

    Maurya, Yogesh Kumar; Ishikawa, Takahiro; Kawabe, Yasunori; Ishida, Masatoshi; Toganoh, Motoki; Mori, Shigeki; Yasutake, Yuhsuke; Fukatsu, Susumu; Furuta, Hiroyuki

    2016-06-20

    Novel near-infrared phosphorescent iridium(III) complexes based on benzo-annulated N-linked corrole analogue (termed as benzonorrole) were synthesized. The structures of the complexes revealed octahedral coordination geometries involving an organometallic iridium-carbon bond with two external axial ligands. Interestingly, the iridium(III) complex exhibits near-infrared phosphorescence at room temperature at wavelengths beyond 900 nm. The significant redshift of the emission, as compared to the corrole congener, is originated from the ligand-centered triplet character. The fine-tuning of the photophysical properties of the complexes was achieved by introducing electron-donating and electron-withdrawing substituents on the axial pyridine ligands. PMID:27249778

  10. Non-local means-based nonuniformity correction for infrared focal-plane array detectors

    NASA Astrophysics Data System (ADS)

    Yu, Hui; Zhang, Zhi-jie; Chen, Fu-sheng; Wang, Chen-sheng

    2014-11-01

    The infrared imaging systems are normally based on the infrared focal-plane array (IRFPA) which can be considered as an array of independent detectors aligned at the focal plane of the imaging system. Unfortunately, every detector on the IRFPA may have a different response to the same input infrared signal which is known as the nonuniformity problem. Then we can observe the fixed pattern noise (FPN) from the resulting images. Standard nonuniformity correction (NUC) methods need to be recalibrated after a short period of time due the temporal drift of the FPN. Scene-based nonuniformity correction (NUC) techniques eliminate the need for calibration by correction coefficients based on the scene being viewed. However, in the scene-based NUC method the problem of ghosting artifacts widely seriously decreases the image quality, which can degrade the performance of many applications such as target detection and track. This paper proposed an improved scene-based method based on the retina-like neural network approach. The method incorporates the use of non-local means (NLM) method into the estimation of the gain and the offset of each detector. This method can not only estimates the accurate correction coefficient but also restrict the ghosting artifacts efficiently. The proposed method relies on the use of NLM method which is a very successful image denoising method. And then the NLM used here can preserve the image edges efficiently and obtain a reliable spatial estimation. We tested the proposed NUC method by applying it to an IR sequence of frames. The performance of the proposed method was compared the other well-established adaptive NUC techniques.

  11. Far infrared supplement: Catalog of infrared observations

    NASA Technical Reports Server (NTRS)

    Gezari, D. Y.; Schmitz, M.; Mead, J. M.

    1982-01-01

    The development of a new generation of orbital, airborne and ground-based infrared astronomical observatory facilities, including the infrared astronomical satellite (IRAS), the cosmic background explorer (COBE), the NASA Kuiper airborne observatory, and the NASA infrared telescope facility, intensified the need for a comprehensive, machine-readable data base and catalog of current infrared astronomical observations. The Infrared Astronomical Data Base and its principal data product, this catalog, comprise a machine-readable library of infrared (1 micrometer to 1000 micrometers) astronomical observations published in the scientific literature since 1965.

  12. Space-based infrared scanning sensor LOS determination and calibration using star observation

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Xu, Zhan; An, Wei; Deng, Xin-Pu; Yang, Jun-Gang

    2015-10-01

    This paper provides a novel methodology for removing sensor bias from a space based infrared (IR) system (SBIRS) through the use of stars detected in the background field of the sensor. Space based IR system uses the LOS (line of sight) of target for target location. LOS determination and calibration is the key precondition of accurate location and tracking of targets in Space based IR system and the LOS calibration of scanning sensor is one of the difficulties. The subsequent changes of sensor bias are not been taking into account in the conventional LOS determination and calibration process. Based on the analysis of the imaging process of scanning sensor, a theoretical model based on the estimation of bias angles using star observation is proposed. By establishing the process model of the bias angles and the observation model of stars, using an extended Kalman filter (EKF) to estimate the bias angles, and then calibrating the sensor LOS. Time domain simulations results indicate that the proposed method has a high precision and smooth performance for sensor LOS determination and calibration. The timeliness and precision of target tracking process in the space based infrared (IR) tracking system could be met with the proposed algorithm.

  13. Trends in correlation-based pattern recognition and tracking in forward-looking infrared imagery.

    PubMed

    Alam, Mohammad S; Bhuiyan, Sharif M A

    2014-01-01

    In this paper, we review the recent trends and advancements on correlation-based pattern recognition and tracking in forward-looking infrared (FLIR) imagery. In particular, we discuss matched filter-based correlation techniques for target detection and tracking which are widely used for various real time applications. We analyze and present test results involving recently reported matched filters such as the maximum average correlation height (MACH) filter and its variants, and distance classifier correlation filter (DCCF) and its variants. Test results are presented for both single/multiple target detection and tracking using various real-life FLIR image sequences. PMID:25061840

  14. Infrared laser-based monitoring of the silane dissociation during deposition of silicon thin films

    SciTech Connect

    Bartlome, R.; Feltrin, A.; Ballif, C.

    2009-05-18

    The silane dissociation efficiency, or depletion fraction, is an important plasma parameter by means of which the film growth rate and the amorphous-to-microcrystalline silicon transition regime can be monitored in situ. In this letter we implement a homebuilt quantum cascade laser-based absorption spectrometer to measure the silane dissociation efficiency in an industrial plasma-enhanced chemical vapor deposition system. This infrared laser-based diagnostic technique is compact, sensitive, and nonintrusive. Its resolution is good enough to resolve Doppler-broadened rotovibrational absorption lines of silane. The latter feature various absorption strengths, thereby enabling depletion measurements over a wide range of process conditions.

  15. Concept for fiber-based near-infrared interferometry of highest frequency resolution

    NASA Astrophysics Data System (ADS)

    Michael, E. A.; Besser, F.; Prado, R.; Pallanca, L.

    2014-07-01

    We are presenting first experimental results for subsystems of a low-cost near-infrared heterodyne interferometer concept based on commercial 1.55μm fiber-components with relative phase-stabilization between both telescopes, a shot noise limited heterodyne scheme with ambient temperature operated photodiodes, an ultra-coherent fiber laser, and a ROACH-based correlator. After we worked on a first demonstration with two 14" amateur telescopes on Betelgeuse, the concept should be upgradable to connect mid- or large-class telescopes, also given that the employed fiber phase stabilization scheme will enable the operation of long baselines.

  16. Trends in Correlation-Based Pattern Recognition and Tracking in Forward-Looking Infrared Imagery

    PubMed Central

    Alam, Mohammad S.; Bhuiyan, Sharif M. A.

    2014-01-01

    In this paper, we review the recent trends and advancements on correlation-based pattern recognition and tracking in forward-looking infrared (FLIR) imagery. In particular, we discuss matched filter-based correlation techniques for target detection and tracking which are widely used for various real time applications. We analyze and present test results involving recently reported matched filters such as the maximum average correlation height (MACH) filter and its variants, and distance classifier correlation filter (DCCF) and its variants. Test results are presented for both single/multiple target detection and tracking using various real-life FLIR image sequences. PMID:25061840

  17. Infrared image segmentation method based on spatial coherence histogram and maximum entropy

    NASA Astrophysics Data System (ADS)

    Liu, Songtao; Shen, Tongsheng; Dai, Yao

    2014-11-01

    In order to segment the target well and suppress background noises effectively, an infrared image segmentation method based on spatial coherence histogram and maximum entropy is proposed. First, spatial coherence histogram is presented by weighting the importance of the different position of these pixels with the same gray-level, which is obtained by computing their local density. Then, after enhancing the image by spatial coherence histogram, 1D maximum entropy method is used to segment the image. The novel method can not only get better segmentation results, but also have a faster computation time than traditional 2D histogram-based segmentation methods.

  18. Operating distance calculation of ground-based and air-based infrared system based on Lowtran7

    NASA Astrophysics Data System (ADS)

    Ren, Kan; Tian, Jie; Gu, Guohua; Chen, Qian

    2016-07-01

    In this paper, the infrared system operating distance model of point target based on the contrast is used, starting from the target radiance and atmospheric transmission parameters in the operating distance formula. The radiance of different point targets detected by ground-based and air-based detector are analyzed, and the spectral division method is used for the integration of target and background radiance, the databases of atmospheric spectral radiance and transmittance are established by calling Lowtran7. A new method for solving the operating distance formula is proposed. And the operating distance calculation system is established, which improves the efficiency and accuracy of calculation. The databases of atmospheric spectral radiance and transmittance of five meteorological conditions are generated, and the variations of them with wavelength and range are given. The atmospheric radiance of infinite transmission range can be considered as the atmospheric radiance of 100 km by calculating the integration of wavelength. The targets and detectors parameters are set to be simulated by using the generated database. The operating distance of each zenith angle is calculated, and spatial distribution of operating distance is given in the meteorological condition of mid latitude summer.

  19. Monitoring enzyme-catalyzed reactions in micromachined nanoliter wells using a conventional microscope-based microarray reader

    NASA Astrophysics Data System (ADS)

    van den Doel, L. Richard; Moerman, R.; van Dedem, G. W. K.; Young, Ian T.; van Vliet, Lucas J.

    2002-06-01

    Yeast-Saccharomyces cerevisiae - it widely used as a model system for other higher eukaryotes, including man. One of the basic fermentation processes in yeast is the glycolytic pathway, which is the conversion of glucose to ethanol and carbon dioxide. This pathway consists of 12 enzyme-catalyzed reactions. With the approach of microarray technology we want to explore the metabolic regulation of this pathway in yeast. This paper will focus on the design of a conventional microscope based microarray reader, which is used to monitor these enzymatic reactions in microarrays. These microarrays are fabricated in silicon and have sizes of 300 by 300 micrometers 2. The depth varies from 20 to 50 micrometers . Enzyme activity levels can be derived by monitoring the production or consumption rate of NAD(P)H, which is excited at 360nm and emits around 450nm. This fluorophore is involved in all 12 reactions of the pathway. The microarray reader is equipped with a back-illuminated CCD camera in order to obtain a high quantum efficiency for the lower wavelengths. The dynamic range of our microarray reader varies form 5(mu) Molar to 1mMolar NAD(P)H. With this microarray reader enzyme activity levels down to 0.01 unit per milliliter can be monitored. The acquisition time per well is 0.1s. The total scan cycle time for a 5 X 5 microarray is less than half a minute. The number of cycles for a proper estimation of the enzyme activity is inversely proportional to the enzyme activity: long measurement times are needed to determine low enzyme activity levels.

  20. [Study on Trace Water Influence on Electrical Properties of Insulating Oil Based on the Mid-Infrared Spectrum Analysis].

    PubMed

    Chen, Bin; Wu, Hong-yang; Han, Chao; Yan, Huan; Liu, Ge

    2015-10-01

    Trace water has a significant impact on the electrical performances of the insulating oil, such as the dielectric loss factor, resistivity. So there is an important significance to investigate the influence of insulating oil by trace water, and monitor its operating status with effective measures. First, it is necessary to prepare the insulating oil samples with different water content and treat them 8 hours with ultrasonic oscillator, and observe microscopic images about the water-oil mixtures in order to study their relative uniformity and stable time, in the way it can be concluded that the relative uniformity can be kept favorable during the 25 min stable time for free water and emulsification water in oil; Based on this conclusion, the dielectric loss factor, resistivity were tested and the electrical performances of insulating oil with different water content in oil can obtained by analyzing these data; Then, the absorbance value of the different water content in oil at the spectral wave number of 1 640, 3 400, 3 450, 3 615 cm(-1), with the mid-infrared spectral scanning and analyzing to the different water content in oil, Therefore, combined the water absorbance values by the mid-infrared spectral scanning and analyzing with the experimental data of dielectric loss factor value, resistivity value of oil samples. The results shows that the absorbance value of the different water content in oil has a significant difference at the spectral wave number of 1 640, 3 400, 3450, 3 615 cm(-1), their correlation coefficient are 0.964 1, 0.984 8, 0.984 5, 0.944 0 between the absorbance value and water content at the spectral wave number of 1 640, 3 400, 3 450, 3 615 cm(-1), it can be obtained that the absorbance value of sample of moisture in the corresponding characteristic wave number can better reflect the change trend of water content; there is the highly relative of water absorbance values at the spectral wave number of 3 400 and 3 450 cm(-1) with the trends of

  1. Determination of melamine of milk based on two-dimensional correlation infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Yang, Ren-jie; Liu, Rong; Xu, Kexin

    2012-03-01

    The adulteration of milk with harmful substances is a threat to public health and beyond question a serious crime. In order to develop a rapid, cost-effective, high-throughput analysis method for detecting of adulterants in milk, the discriminative analysis of melamine is established in milk based on the two-dimensional (2D) correlation infrared spectroscopy in present paper. Pure milk samples and adulterated milk samples with different content of melamine were prepared. Then the Fourier Transform Infrared spectra of all samples were measured at room temperature. The characteristics of pure milk and adulterated milk were studied by one-dimensional spectra. The 2D NIR and 2D IR correlation spectroscopy were calculated under the perturbation of adulteration concentration. In the range from 1400 to 1800 cm-1, two strong autopeaks were aroused by melamine in milk at 1464 cm-1 and 1560 cm-1 in synchronous spectrum. At the same time, the 1560 cm-1 band does not share cross peak with the 1464 cm-1 band, which further confirm that the two bands have the same origin. Also in the range from 4200 to 4800 cm-1, the autopeak was shown at 4648 cm-1 in synchronous spectrum of melamine in milk. 2D NIR-IR hetero-spectral correlation analysis confirmed that the bands at 1464, 1560 and 4648 cm-1 had the same origin. The results demonstrated that the adulterant can be discriminated correctly by 2D correlation infrared spectroscopy.

  2. Captive flight test-based infrared validation of a hardware-in-the-loop simulation

    NASA Astrophysics Data System (ADS)

    Sanders, Jeffrey S.; Roland, Randall; Cosby, David S.; Saylor, Daniel A.; Harrison, Kenneth R.

    2000-07-01

    This paper describes infrared (IR) scene generation and validation activities at the U.S. Army Aviation and Missile Command's (AMCOM) Dual-Mode Hardware-in-the-Loop (HWIL) Simulation. The HWIL simulation validation results are based on comparison of infrared seeker data collected in the HWIL simulation to infrared seeker data collected during captive flight tests (CFTs). Use of CFT data allows a simulation developer to quantify not only the radiometric fidelity of the simulation inputs, but also the effects that any limitations of the inputs may have on simulation validity with respect to a particular seeker and its algorithms. Validation of this type of simulation is a complex process and all aspects of the validation are covered. Topics include real-time IR signature modeling and validation, simulation output verification, projected energy verification, and total end-to-end simulation validation. Also included are descriptions of the different types of CFT scenarios necessary for simulation validation and the comparison methodologies used for each case.

  3. Infrared micro-scanning error compensation algorithm based on edge location

    NASA Astrophysics Data System (ADS)

    Gao, Hang; Chen, Qian; Sui, Xiubao

    2015-03-01

    For area-array thermal imaging devices, an essential factor affecting the system imaging quality is the sub-sampling caused by oversized discrete sampling pitch. In order to obtain higher spatial resolution, staring infrared focal plane array (IRFPA) gets multi-frame sub-sampling images by micro-scanning movement to achieve an adequate spatial sampling frequency. However, influenced by external environment and the accuracy of the scanning system itself, the relative displacement between the detector and the scene cannot be absolutely precisely controlled, but exist some error, which will affect the final performance of the reconstructed high-resolution image. We analyzed the distribution of the error and then proposed an infrared micro-scanning error compensation algorithm based on edge location, which is inspired by human retina fixational eye movement pattern. It first locates the edge point in the reconstruction unit and finds the corresponding characteristic values. Later on, matches the characteristic value with the fixed templates and reorders the pixel responses in reconstruction unit utilizing the gray correlation. Finally, it compensates the error real-timely through repeated update and iteration. We apply the algorithm in video sequences acquired by 4-step infrared micro-scanning system. The experiment results show that when aligning to a static scene or stationary region in dynamic scene, the algorithm possesses good resolution enhancement effect, particularly, can improve the clarity and the accuracy of static image edge details.

  4. A novel objective sour taste evaluation method based on near-infrared spectroscopy.

    PubMed

    Hoshi, Ayaka; Aoki, Soichiro; Kouno, Emi; Ogasawara, Masashi; Onaka, Takashi; Miura, Yutaka; Mamiya, Kanji

    2014-05-01

    One of the most important themes in the development of foods and drinks is the accurate evaluation of taste properties. In general, a sensory evaluation system is frequently used for evaluating food and drink. This method, which is dependent on human senses, is highly sensitive but is influenced by the eating experience and food palatability of individuals, leading to subjective results. Therefore, a more effective method for objectively estimating taste properties is required. Here we show that salivary hemodynamic signals, as measured by near-infrared spectroscopy, are a useful objective indicator for evaluating sour taste stimulus. In addition, the hemodynamic responses of the parotid gland are closely correlated to the salivary secretion volume of the parotid gland in response to basic taste stimuli and respond to stimuli independently of the hedonic aspect. Moreover, we examined the hemodynamic responses to complex taste stimuli in food-based solutions and demonstrated for the first time that the complicated phenomenon of the "masking effect," which decreases taste intensity despite the additional taste components, can be successfully detected by near-infrared spectroscopy. In summary, this study is the first to demonstrate near-infrared spectroscopy as a novel tool for objectively evaluating complex sour taste properties in foods and drinks. PMID:24474216

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

    PubMed Central

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

    2016-01-01

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

  6. Novel infrared image enhancement technology based on the frequency compensation approach

    NASA Astrophysics Data System (ADS)

    Qi, Yuhua; He, Rulong; Lin, Haitao

    2016-05-01

    A novel infrared image enhancement method has been proposed in this paper. Our aim is to develop a detail enhancement method which is focused on the frequency feature of the image. The proposed method is following the most popular strategy of enhancing the infrared images nowadays, but concentrating on the frequency domain. Firstly, the original image is separated by a guided image filter into detail layer and the base layer. Quite unlike the traditional methods, we use the guided image filter to eliminate most of the noise and weak signal of the scenario. Then, by a designed iteration process, the higher frequency of the scenario will be calculated back and add to the detail layer. The noise will not be enhanced because the iteration is only focused on the leftover scenario frequency. We run many tests on the raw data captured by the 320 × 256 HgCdTe cooled thermal imager, and make a comparison between our approach with the previous method of bilateral filtering digital detail enhancement and guided image filtering digital detail enhancement. Figures and analytical data show that our method is better than the previous proposed researches. Our method could effectively process the infrared image with less noise and artifacts, which has potential applications in testing, manufacturing, chemical imaging, night vision, and surveillance security.

  7. Precise Temperature Mapping of GaN-Based LEDs by Quantitative Infrared Micro-Thermography

    PubMed Central

    Chang, Ki Soo; Yang, Sun Choel; Kim, Jae-Young; Kook, Myung Ho; Ryu, Seon Young; Choi, Hae Young; Kim, Geon Hee

    2012-01-01

    A method of measuring the precise temperature distribution of GaN-based light-emitting diodes (LEDs) by quantitative infrared micro-thermography is reported. To reduce the calibration error, the same measuring conditions were used for both calibration and thermal imaging; calibration was conducted on a highly emissive black-painted area on a dummy sapphire wafer loaded near the LED wafer on a thermoelectric cooler mount. We used infrared thermal radiation images of the black-painted area on the dummy wafer and an unbiased LED wafer at two different temperatures to determine the factors that degrade the accuracy of temperature measurement, i.e., the non-uniform response of the instrument, superimposed offset radiation, reflected radiation, and emissivity map of the LED surface. By correcting these factors from the measured infrared thermal radiation images of biased LEDs, we determined a precise absolute temperature image. Consequently, we could observe from where the local self-heat emerges and how it distributes on the emitting area of the LEDs. The experimental results demonstrated that highly localized self-heating and a remarkable temperature gradient, which are detrimental to LED performance and reliability, arise near the p-contact edge of the LED surface at high injection levels owing to the current crowding effect. PMID:22666050

  8. Precise temperature mapping of GaN-based LEDs by quantitative infrared micro-thermography.

    PubMed

    Chang, Ki Soo; Yang, Sun Choel; Kim, Jae-Young; Kook, Myung Ho; Ryu, Seon Young; Choi, Hae Young; Kim, Geon Hee

    2012-01-01

    A method of measuring the precise temperature distribution of GaN-based light-emitting diodes (LEDs) by quantitative infrared micro-thermography is reported. To reduce the calibration error, the same measuring conditions were used for both calibration and thermal imaging; calibration was conducted on a highly emissive black-painted area on a dummy sapphire wafer loaded near the LED wafer on a thermoelectric cooler mount. We used infrared thermal radiation images of the black-painted area on the dummy wafer and an unbiased LED wafer at two different temperatures to determine the factors that degrade the accuracy of temperature measurement, i.e., the non-uniform response of the instrument, superimposed offset radiation, reflected radiation, and emissivity map of the LED surface. By correcting these factors from the measured infrared thermal radiation images of biased LEDs, we determined a precise absolute temperature image. Consequently, we could observe from where the local self-heat emerges and how it distributes on the emitting area of the LEDs. The experimental results demonstrated that highly localized self-heating and a remarkable temperature gradient, which are detrimental to LED performance and reliability, arise near the p-contact edge of the LED surface at high injection levels owing to the current crowding effect. PMID:22666050

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2014-01-01

    Geostationary meteorological satellite infrared (IR) channel data contain important spectral information for meteorological research and applications, but their spatial resolution is relatively low. The objective of this study is to obtain higher-resolution IR images. One common method of increasing resolution fuses the IR data with high-resolution visible (VIS) channel data. However, most existing image fusion methods focus only on visual performance, and often fail to take into account the thermal physical properties of the IR images. As a result, spectral distortion occurs frequently. To tackle this problem, we propose a thermal physical properties-based correction method for fusing geostationary meteorological satellite IR and VIS images. In our two-step process, the high-resolution structural features of the VIS image are first extracted and incorporated into the IR image using regular multi-resolution fusion approach, such as the multiwavelet analysis. This step significantly increases the visual details in the IR image, but fake thermal information may be included. Next, the Stefan-Boltzmann Law is applied to correct the distortion, to retain or recover the thermal infrared nature of the fused image. The results of both the qualitative and quantitative evaluation demonstrate that the proposed physical correction method both improves the spatial resolution and preserves the infrared thermal properties. PMID:24919017

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

    NASA Astrophysics Data System (ADS)

    Yun, Xiao; Jing, Zhongliang; Jin, Bo

    2016-04-01

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

  12. [Detection of reducing sugar content of potato granules based on wavelet compression by near infrared spectroscopy].

    PubMed

    Dong, Xiao-Ling; Sun, Xu-Dong

    2013-12-01

    The feasibility was explored in determination of reducing sugar content of potato granules based on wavelet compression algorithm combined with near-infrared spectroscopy. The spectra of 250 potato granules samples were recorded by Fourier transform near-infrared spectrometer in the range of 4000- 10000 cm-1. The three parameters of vanishing moments, wavelet coefficients and principal component factor were optimized. The optimization results of three parameters were 10, 100 and 20, respectively. The original spectra of 1501 spectral variables were transfered to 100 wavelet coefficients using db wavelet function. The partial least squares (PLS) calibration models were developed by 1501 spectral variables and 100 wavelet coefficients. Sixty two unknown samples of prediction set were applied to evaluate the performance of PLS models. By comparison, the optimal result was obtained by wavelet compression combined with PLS calibration model. The correlation coefficient of prediction and root mean square error of prediction were 0.98 and 0.181%, respectively. Experimental results show that the dimensions of spectral data were reduced, scarcely losing effective information by wavelet compression algorithm combined with near-infrared spectroscopy technology in determination of reducing sugar in potato granules. The PLS model is simplified, and the predictive ability is improved. PMID:24611373

  13. Research on infrared-image denoising algorithm based on the noise analysis of the detector

    NASA Astrophysics Data System (ADS)

    Liu, Songtao; Zhou, Xiaodong; Shen, Tongsheng; Han, Yanli

    2005-01-01

    Since the conventional denoising algorithms have not considered the influence of certain concrete detector, they are not very effective to remove various noises contained in the low signal-to-noise ration infrared image. In this paper, a new thinking for infrared image denoising is proposed, which is based on the noise analyses of detector with an example of L model infrared multi-element detector. According to the noise analyses of this detector, the emphasis is placed on how to filter white noise and fractal noise in the preprocessing phase. Wavelet analysis is a good tool for analyzing 1/f process. 1/f process can be viewed as white noise approximately since its wavelet coefficients are stationary and uncorrelated. So if wavelet transform is adopted, the problem of removing white noise and fraction noise is simplified as the only one problem, i.e., removing white noise. To address this problem, a new wavelet domain adaptive wiener filtering algorithm is presented. From the viewpoint of quantitative and qualitative analyses, the filtering effect of our method is compared with those of traditional median filter, mean filter and wavelet thresholding algorithm in detail. The results show that our method can reduce various noises effectively and raise the ratio of signal-to-noise evidently.

  14. Improved optical resonance in mid-infrared GaAs-based modulating retro-reflectors

    NASA Astrophysics Data System (ADS)

    Ikpe, Stanley; Triplett, Gregory

    2015-05-01

    In this work, we studied a mid-infrared modulating retro-reflector (MRR) design that is GaAs-based because of the flexibility to monolithically incorporate reflective optics along with quantum well modulator region. Using solid-source molecular beam epitaxy, we produced MRR devices, where the GaAs quantum well(s) in the modulator region contained AlxGa1-xAs barriers to tune the wavelength selectivity beyond three microns. The width of the quantum well was also adjusted in order to achieve free electron absorption within the confined energy subbands and modified by way of the quantum confined Stark effect. When the applied electric field varies in polarity, intensity, or frequency, the fabricated MRRs behave as an optional shutter--absorbing or transmitting the incident mid-infrared energy depending on the applied field. Our work shows that the ability for the modulating region to effectively act as a shutter for mid-infrared radiation depends on the number of cascading quantum wells, though increasing the number of wells directly increases the overall thickness of the modulating region and adversely affects the reflected power of the mid-infrared modulated beam. The shutter operation was achieved by applying an alternating square bias across the QWM region, and the speed at which the quantum wells switch from absorbing to non-absorbing was dependent on the physical size of the device. Increasing the physical size increases the associated device capacitance. The maximum achievable contrast ratio for these devices is calculated to be 1.6:1 for applied voltages between 12V and 25V.

  15. Comparison studies of infrared photodetectors with a quantum-dot and a quantum-wire base

    NASA Astrophysics Data System (ADS)

    El Tokhy, M. S.; Mahmoud, I. I.; Konber, H. A.

    2011-12-01

    This paper mainly presents a theoretical analysis for the characteristics of quantum dot infrared photodetectors (QDIPs) and quantum wire infrared photodetectors (QRIPs). The paper introduces a unique mathematical model of solving Poisson's equations with the usage of Lambert W functions for infrared detectors' structures based on quantum effects. Even though QRIPs and QDIPs have been the subject of extensive researches and development during the past decade, it is still essential to implement theoretical models allowing to estimate the ultimate performance of those detectors such as photocurrent and its figure-of-merit detectivity vs. various parameter conditions such as applied voltage, number of quantum wire layers, quantum dot layers, lateral characteristic size, doping density, operation temperature, and structural parameters of the quantum dots (QDs), and quantum wires (QRs). A comparison is made between the computed results of the implemented models and fine agreements are observed. It is concluded from the obtained results that the total detectivity of QDIPs can be significantly lower than that in the QRIPs and main features of the QRIPs such as large gap between the induced photocurrent and dark current of QRIP which allows for overcoming the problems in the QDIPs. This confirms what is evaluated before in the literature. It is evident that by increasing the QD/QR absorption volume in QDIPs/QRIPs as well as by separating the dark current and photocurrents, the specific detectivity can be improved and consequently the devices can operate at higher temperatures. It is an interesting result and it may be benefit to the development of QDIP and QRIP for infrared sensing applications.

  16. Particle filter-based relative rolling estimation algorithm for non-cooperative infrared spacecraft

    NASA Astrophysics Data System (ADS)

    Li, Zhengzhou; Ge, Fengzeng; Chen, Wenhao; Shao, Wanxing; Liu, Bing; Cheng, Bei

    2016-09-01

    The issue of feature point mismatching among infrared image sequence would bring big challenge to estimating the relative motion of non-cooperative spacecraft for it couldn't provide the prior knowledge about its geometric structure and motion pattern. The paper introduces particle filter to precisely match the feature points within a desired region predicted by a kinetic equation, and presents a least square estimation-based algorithm to measure the relative rolling motion of non-cooperative spacecraft. The state transition equation and the measurement update equation of non-cooperative spacecraft are represented by establishing its kinetic equations, and then the relative pose measurement is converted to the maximum posteriori probability estimation via assuming the uncertainties about geometric structure and motion pattern as random and time-varying variables. These uncertainties would be interpreted and even solved through continuously measuring the image feature points of the rotating non-cooperative infrared spacecraft. Subsequently, the feature point is matched within a predicted region among sequence infrared image using particle filter algorithm to overcome the position estimation noise caused by the uncertainties of geometric structure and motion pattern. Finally, the position parameters including rotation motion are estimated by means of solving the minimum error of feature point mismatching using least square estimate theory. Both simulated and real infrared image sequences are induced in the experiment to evaluate the performance of the relative rolling estimation, and the experimental data show that the rolling motion estimated by the proposed algorithm is more robust to the feature extraction noise and various rotation speed. Meanwhile, the relative rolling estimation error would increase dramatically with distance and rotation speed increasing.

  17. Toward autonomous surface-based infrared remote sensing of polar clouds: cloud-height retrievals

    NASA Astrophysics Data System (ADS)

    Rowe, Penny M.; Cox, Christopher J.; Walden, Von P.

    2016-08-01

    Polar regions are characterized by their remoteness, making measurements challenging, but an improved knowledge of clouds and radiation is necessary to understand polar climate change. Infrared radiance spectrometers can operate continuously from the surface and have low power requirements relative to active sensors. Here we explore the feasibility of retrieving cloud height with an infrared spectrometer that would be designed for use in remote polar locations. Using a wide variety of simulated spectra of mixed-phase polar clouds at varying instrument resolutions, retrieval accuracy is explored using the CO2 slicing/sorting and the minimum local emissivity variance (MLEV) methods. In the absence of imposed errors and for clouds with optical depths greater than ˜ 0.3, cloud-height retrievals from simulated spectra using CO2 slicing/sorting and MLEV are found to have roughly equivalent high accuracies: at an instrument resolution of 0.5 cm-1, mean biases are found to be ˜ 0.2 km for clouds with bases below 2 and -0.2 km for higher clouds. Accuracy is found to decrease with coarsening resolution and become worse overall for MLEV than for CO2 slicing/sorting; however, the two methods have differing sensitivity to different sources of error, suggesting an approach that combines them. For expected errors in the atmospheric state as well as both instrument noise and bias of 0.2 mW/(m2 sr cm-1), at a resolution of 4 cm-1, average retrieval errors are found to be less than ˜ 0.5 km for cloud bases within 1 km of the surface, increasing to ˜ 1.5 km at 4 km. This sensitivity indicates that a portable, surface-based infrared radiance spectrometer could provide an important complement in remote locations to satellite-based measurements, for which retrievals of low-level cloud are challenging.

  18. Investigation of fluids as filling of a biomimetic infrared sensor based on the infrared receptors of pyrophilous insects

    NASA Astrophysics Data System (ADS)

    Kahl, T.; Li, N.; Schmitz, H.; Bousack, H.

    2012-04-01

    The beetle Melanophila acuminata is highly dependent on forest fires. The burned wood serves as food for the larvae and the adults copulate on the burned areas to put their eggs in the freshly burned trees. To be able to detect forest fires from great distances the beetle developed a highly sensitive infrared receptor which works according to a photomechanical principle. The beetle has two pit organs, one on each lateral side, of which each houses around 70 dome shaped infrared receptors. These IR-receptors consist of a hard outer cuticular shell and an inner microfluidic core. When IR-radiation is absorbed, the pressure in the core increases due to the thermal expansion. This results in a deflection of a dendritic tip of a mechanosensitiv neuron which generates the signal. This biological principle was transferred into a new kind of un-cooled technical infrared receptor. To demonstrate the functional principle and the feasibility of this IR-sensor a macroscopic demonstrator sensor was build. It consisted of an inner fluid filled cavity (pressure chamber), an IR-transmissive window and a membrane. The deflection of the membrane due to the absorbed IR-energy was measured by a sensitive commercial capacitive sensor. In the experiments ethanol with added black ink, a mix of ethanol and glucose with additional absorber, air with additional absorber and water were used as fillings of the cavity and compared against each other. In order to get insights into the physics of the results of the experiments accompanying simulations using FEM methods and analytical calculations have been performed. The results showed that ethanol and air as fillings of the cavity caused the largest deflection of the membrane. Furthermore it turned out that the thermal expansion of the sensor housing material has an important influence. The comparison of the measured deflection with calculated deflections showed a good concordance.

  19. Automated cloud classification using a ground based infra-red camera and texture analysis techniques

    NASA Astrophysics Data System (ADS)

    Rumi, Emal; Kerr, David; Coupland, Jeremy M.; Sandford, Andrew P.; Brettle, Mike J.

    2013-10-01

    Clouds play an important role in influencing the dynamics of local and global weather and climate conditions. Continuous monitoring of clouds is vital for weather forecasting and for air-traffic control. Convective clouds such as Towering Cumulus (TCU) and Cumulonimbus clouds (CB) are associated with thunderstorms, turbulence and atmospheric instability. Human observers periodically report the presence of CB and TCU clouds during operational hours at airports and observatories; however such observations are expensive and time limited. Robust, automatic classification of cloud type using infrared ground-based instrumentation offers the advantage of continuous, real-time (24/7) data capture and the representation of cloud structure in the form of a thermal map, which can greatly help to characterise certain cloud formations. The work presented here utilised a ground based infrared (8-14 μm) imaging device mounted on a pan/tilt unit for capturing high spatial resolution sky images. These images were processed to extract 45 separate textural features using statistical and spatial frequency based analytical techniques. These features were used to train a weighted k-nearest neighbour (KNN) classifier in order to determine cloud type. Ground truth data were obtained by inspection of images captured simultaneously from a visible wavelength colour camera at the same installation, with approximately the same field of view as the infrared device. These images were classified by a trained cloud observer. Results from the KNN classifier gave an encouraging success rate. A Probability of Detection (POD) of up to 90% with a Probability of False Alarm (POFA) as low as 16% was achieved.

  20. Biodiesel classification by base stock type (vegetable oil) using near infrared spectroscopy data.

    PubMed

    Balabin, Roman M; Safieva, Ravilya Z

    2011-03-18

    The use of biofuels, such as bioethanol or biodiesel, has rapidly increased in the last few years. Near infrared (near-IR, NIR, or NIRS) spectroscopy (>4000cm(-1)) has previously been reported as a cheap and fast alternative for biodiesel quality control when compared with infrared, Raman, or nuclear magnetic resonance (NMR) methods; in addition, NIR can easily be done in real time (on-line). In this proof-of-principle paper, we attempt to find a correlation between the near infrared spectrum of a biodiesel sample and its base stock. This correlation is used to classify fuel samples into 10 groups according to their origin (vegetable oil): sunflower, coconut, palm, soy/soya, cottonseed, castor, Jatropha, etc. Principal component analysis (PCA) is used for outlier detection and dimensionality reduction of the NIR spectral data. Four different multivariate data analysis techniques are used to solve the classification problem, including regularized discriminant analysis (RDA), partial least squares method/projection on latent structures (PLS-DA), K-nearest neighbors (KNN) technique, and support vector machines (SVMs). Classifying biodiesel by feedstock (base stock) type can be successfully solved with modern machine learning techniques and NIR spectroscopy data. KNN and SVM methods were found to be highly effective for biodiesel classification by feedstock oil type. A classification error (E) of less than 5% can be reached using an SVM-based approach. If computational time is an important consideration, the KNN technique (E=6.2%) can be recommended for practical (industrial) implementation. Comparison with gasoline and motor oil data shows the relative simplicity of this methodology for biodiesel classification. PMID:21397073

  1. A dual-channel fusion system of visual and infrared images based on color transfer

    NASA Astrophysics Data System (ADS)

    Pei, Chuang; Jiang, Xiao-yu; Zhang, Peng-wei; Liang, Hao-cong

    2013-09-01

    A dual-channel fusion system of visual and infrared images based on color transfer The increasing availability and deployment of imaging sensors operating in multiple spectrums has led to a large research effort in image fusion, resulting in a plethora of pixel-level image fusion algorithms. However, most of these algorithms have gray or false color fusion results which are not adapt to human vision. Transfer color from a day-time reference image to get natural color fusion result is an effective way to solve this problem, but the computation cost of color transfer is expensive and can't meet the request of real-time image processing. We developed a dual-channel infrared and visual images fusion system based on TMS320DM642 digital signal processing chip. The system is divided into image acquisition and registration unit, image fusion processing unit, system control unit and image fusion result out-put unit. The image registration of dual-channel images is realized by combining hardware and software methods in the system. False color image fusion algorithm in RGB color space is used to get R-G fused image, then the system chooses a reference image to transfer color to the fusion result. A color lookup table based on statistical properties of images is proposed to solve the complexity computation problem in color transfer. The mapping calculation between the standard lookup table and the improved color lookup table is simple and only once for a fixed scene. The real-time fusion and natural colorization of infrared and visual images are realized by this system. The experimental result shows that the color-transferred images have a natural color perception to human eyes, and can highlight the targets effectively with clear background details. Human observers with this system will be able to interpret the image better and faster, thereby improving situational awareness and reducing target detection time.

  2. High dynamic range infrared images detail enhancement based on local edge preserving filter

    NASA Astrophysics Data System (ADS)

    Song, Qiong; Wang, Yuehuan; Bai, Kun

    2016-07-01

    In the field of infrared (IR) image processing, displaying a high dynamic range (HDR) image on a low dynamic range display equipment with a natural visual effect, clear details on local areas and less artifacts is an important issue. In this paper, we present a new approach to display HDR IR images with contrast enhancement. First, the local edge-preserving filter (LEPF) is utilized to separate the image into a base layer and detail layer(s). After the filtering procedure, we use an adaptive Gamma transformation to adjust the gray distribution of the base layer, and stretch the detail layer based on a human visual effect principle. Then, we recombine the detail layer and base layer to obtain the enhance output. Finally, we adjust the luminance of output by applying multiple exposure fusion method. The experimental results demonstrate that our proposed method can provide a significant performance in terms of enhancing details and less artifacts than the state of the arts.

  3. Long wave infrared tunable filter based on guided mode resonant effect

    NASA Astrophysics Data System (ADS)

    Mirotznik, Mark S.; Gupta, Neelam; McElhiney, Morgan; Carey, Victoria

    2016-05-01

    We describe here a tunable long wave infrared (LWIR) band filter based on the guided mode resonant filter (GMRF) effect. The device consists of a subwavelength dielectric grating sandwiched between planar layers of contrasting dielectric materials. Using a rigorous electromagnetic design and analysis method we demonstrate how a strong narrow band reflectance can be induced. Moreover, the resonant wavelength can be easily tuned over the entire 8-12 micron band by mechanically tilting the device with respect to the optical axis. Simulation and experimental results are presented demonstrating the effectiveness of the device.

  4. Uncooled resonant infrared detector based on aluminum nitride piezoelectric film through charge generations and lattice absorptions

    NASA Astrophysics Data System (ADS)

    Ang, W. C.; Kropelnicki, P.; Zhu, Y.; Randles, A. B.; Gu, Y. A.; Leong, K. C.; Tan, C. S.

    2014-05-01

    This Letter demonstrates an aluminum nitride (AlN) based uncooled resonant infrared (IR) detector utilizing the photo-sensitive and piezoelectric properties of polycrystalline AlN. The AlN Lamb wave mode resonator is found responsive to IR illuminations by showing a decrease in the S21 magnitude instead of a resonant frequency shift. A -0.08 dB shift of S21 magnitude was observed for an IR incident power of 647 nW, which translates to a responsivity of 124 kdB/W. Photoresponse is proposed for the IR sensing mechanism through additional charge carriers generation rather than thermal effects.

  5. Noncollinear parametric amplification in the near-infrared based on type-II phase matching

    NASA Astrophysics Data System (ADS)

    Schmidt, C.; Bühler, J.; Heinrich, A.-C.; Leitenstorfer, A.; Brida, D.

    2015-09-01

    Noncollinear parametric amplification based on type-II phase matching for the generation of ultrabroadband and tunable spectra in the near infrared is investigated. In a noncollinear geometry the group velocity matching condition between signal and idler can be obtained in frequently used crystals such as β-barium borate (BBO) even for wavelengths fully located in the anomalous dispersion region. The extremely broadband operation, peculiar tuning possibilities and straightforward experimental implementation with the standard BBO crystal pave the way for a versatile NIR source in ultrafast spectroscopy.

  6. Limiting dark current mechanisms in antimony-based superlattice infrared detectors for the long-wavelength infrared regime

    NASA Astrophysics Data System (ADS)

    Rehm, Robert; Lemke, Florian; Schmitz, Johannes; Wauro, Matthias; Walther, Martin

    2015-06-01

    A detailed understanding of limiting dark current mechanisms in InAs/GaSb type-II superlattice (T2SL) infrared detectors is key to improve the electrooptical performance of these devices. We present a six-component dark current analysis which, for the first time, takes account of sidewall-related dark current contributions in mesa-etched T2SL photodiodes. In a wide temperature range from 30K to 130K, the paper compares limiting mechanisms in two homojunction T2SL photodiode wafers for the long-wavelength infrared regime. While the two epi wafers were fabricated with nominally the same frontside process they were grown on different molecular beam epitaxy systems. In the available literature a limitation by Shockley-Read-Hall processes in the space charge region giving rise to generation-recombination (GR) dark current is the prevailing verdict on the bulk dark current mechanism in T2SL homojunction photodiodes around 77K. In contrast, we find that investigated photodiode wafers are instead limited by the diffusion mechanism and the ohmic shunt component, respectively. Furthermore, our in-depth analysis of the various dark current components has led to an interesting observation on the temperature dependence of the shunt resistance in T2SL homojunction photodiodes. Our results indicate that the GR and the shunt mechanism share the same dependence on bandgap and temperature, i.e., a proportionality to exp(-Eg/2kT).

  7. Parallel microscope-based fluorescence, absorbance and time-of-flight mass spectrometry detection for high performance liquid chromatography and determination of glucosamine in urine.

    PubMed

    Xiong, Bo; Wang, Ling-Ling; Li, Qiong; Nie, Yu-Ting; Cheng, Shuang-Shuang; Zhang, Hui; Sun, Ren-Qiang; Wang, Yu-Jiao; Zhou, Hong-Bin

    2015-11-01

    A parallel microscope-based laser-induced fluorescence (LIF), ultraviolet-visible absorbance (UV) and time-of-flight mass spectrometry (TOF-MS) detection for high performance liquid chromatography (HPLC) was achieved and used to determine glucosamine in urines. First, a reliable and convenient LIF detection was developed based on an inverted microscope and corresponding modulations. Parallel HPLC-LIF/UV/TOF-MS detection was developed by the combination of preceding Microscope-based LIF detection and HPLC coupled with UV and TOF-MS. The proposed setup, due to its parallel scheme, was free of the influence from photo bleaching in LIF detection. Rhodamine B, glutamic acid and glucosamine have been determined to evaluate its performance. Moreover, the proposed strategy was used to determine the glucosamine in urines, and subsequent results suggested that glucosamine, which was widely used in the prevention of the bone arthritis, was metabolized to urines within 4h. Furthermore, its concentration in urines decreased to 5.4mM at 12h. Efficient glucosamine detection was achieved based on a sensitive quantification (LIF), a universal detection (UV) and structural characterizations (TOF-MS). This application indicated that the proposed strategy was sensitive, universal and versatile, and it was capable of improved analysis, especially for analytes with low concentrations in complex samples, compared with conventional HPLC-UV/TOF-MS. PMID:26452822

  8. Packet based serial link realized in FPGA dedicated for high resolution infrared image transmission

    NASA Astrophysics Data System (ADS)

    Bieszczad, Grzegorz

    2015-05-01

    In article the external digital interface specially designed for thermographic camera built in Military University of Technology is described. The aim of article is to illustrate challenges encountered during design process of thermal vision camera especially related to infrared data processing and transmission. Article explains main requirements for interface to transfer Infra-Red or Video digital data and describes the solution which we elaborated based on Low Voltage Differential Signaling (LVDS) physical layer and signaling scheme. Elaborated link for image transmission is built using FPGA integrated circuit with built-in high speed serial transceivers achieving up to 2500Gbps throughput. Image transmission is realized using proprietary packet protocol. Transmission protocol engine was described in VHDL language and tested in FPGA hardware. The link is able to transmit 1280x1024@60Hz 24bit video data using one signal pair. Link was tested to transmit thermal-vision camera picture to remote monitor. Construction of dedicated video link allows to reduce power consumption compared to solutions with ASIC based encoders and decoders realizing video links like DVI or packed based Display Port, with simultaneous reduction of wires needed to establish link to one pair. Article describes functions of modules integrated in FPGA design realizing several functions like: synchronization to video source, video stream packeting, interfacing transceiver module and dynamic clock generation for video standard conversion.

  9. A ground-based near-infrared emission spectrum of the exoplanet HD 189733b.

    PubMed

    Swain, Mark R; Deroo, Pieter; Griffith, Caitlin A; Tinetti, Giovanna; Thatte, Azam; Vasisht, Gautam; Chen, Pin; Bouwman, Jeroen; Crossfield, Ian J; Angerhausen, Daniel; Afonso, Cristina; Henning, Thomas

    2010-02-01

    Detection of molecules using infrared spectroscopy probes the conditions and compositions of exoplanet atmospheres. Water (H(2)O), methane (CH(4)), carbon dioxide (CO(2)), and carbon monoxide (CO) have been detected in two hot Jupiters. These previous results relied on space-based telescopes that do not provide spectroscopic capability in the 2.4-5.2 microm spectral region. Here we report ground-based observations of the dayside emission spectrum for HD 189733b between 2.0-2.4 microm and 3.1-4.1 microm, where we find a bright emission feature. Where overlap with space-based instruments exists, our results are in excellent agreement with previous measurements. A feature at approximately 3.25 microm is unexpected and difficult to explain with models that assume local thermodynamic equilibrium (LTE) conditions at the 1 bar to 1 x 10(-6) bar pressures typically sampled by infrared measurements. The most likely explanation for this feature is that it arises from non-LTE emission from CH(4), similar to what is seen in the atmospheres of planets in our own Solar System. These results suggest that non-LTE effects may need to be considered when interpreting measurements of strongly irradiated exoplanets. PMID:20130645

  10. Infrared image enhancement based on the edge detection and mathematical morphology

    NASA Astrophysics Data System (ADS)

    Zhang, Linlin; Zhao, Yuejin; Dong, Liquan; Liu, Xiaohua; Yu, Xiaomei; Hui, Mei; Chu, Xuhong; Gong, Cheng

    2010-11-01

    The development of the un-cooled infrared imaging technology from military necessity. At present, It is widely applied in industrial, medicine, scientific and technological research and so on. The infrared radiation temperature distribution of the measured object's surface can be observed visually. The collection of infrared images from our laboratory has following characteristics: Strong spatial correlation, Low contrast , Poor visual effect; Without color or shadows because of gray image , and has low resolution; Low definition compare to the visible light image; Many kinds of noise are brought by the random disturbances of the external environment. Digital image processing are widely applied in many areas, it can now be studied up close and in detail in many research field. It has become one kind of important means of the human visual continuation. Traditional methods for image enhancement cannot capture the geometric information of images and tend to amplify noise. In order to remove noise and improve visual effect. Meanwhile, To overcome the above enhancement issues. The mathematical model of FPA unit was constructed based on matrix transformation theory. According to characteristics of FPA, Image enhancement algorithm which combined with mathematical morphology and edge detection are established. First of all, Image profile is obtained by using the edge detection combine with mathematical morphological operators. And then, through filling the template profile by original image to get the ideal background image, The image noise can be removed on the base of the above method. The experiments show that utilizing the proposed algorithm can enhance image detail and the signal to noise ratio.

  11. Long-wavelength infrared photoconductor technology based on epitaxially grown Hg1-xCdxTe

    NASA Astrophysics Data System (ADS)

    Siliquini, John F.; Fynn, Kevin A.; Musca, Charles A.; Nener, Brett D.; Dell, John M.; Faraone, Lorenzo

    1995-09-01

    The performance of Hg1-xCdxTe long wavelength infrared (LWIR) photoconductors is strongly dependent on the semiconductor surface conditions and contact characteristics. In this paper we review these effects in relation to obtaining an optimum device technology suitable for use in two-dimensional infrared focal plane arrays (IRFPAs) based on the fabrication of high performance LWIR photoconductors on epitaxially grown Hg1-xCdxTe. Although the proposed design can be applied to a variety of epitaxially grown Hg1-xCdxTe material, for optimum performance the starting Hg1-xCdxTe semiconductor consists of epitaxially grown heterostructure layers in which a two-dimensional mosaic of lateral design photoconductors are fabricated. The heterostructure layer provides high performance devices at greatly reduced power dissipation levels, while the unique design allows for the high density integration of photoconductors in a two-dimensional array geometry with high fill factor. The proposed photoconductor array with n+ blocking contacts has been experimentally verified in a 3 X 3 array format with all elements in the array exhibiting background limited infrared photodetector (BLIP) performance at 80 K. Performance issues such as response uniformity, pixel yield, fill factor, crosstalk, power dissipation, detector impedance, array architecture, and maximum array size are discussed in relation to the suitability of the proposed photoconductor structure for use in IRFPA modules. It is found that in many cases the proposed photoconductor technology has the potential to deliver significant advantages, such as higher yield, higher fill factor, better uniformity, less crosstalk, and larger potential array size, in comparison to an IRFPA design based on photovoltaic technology.

  12. A near-infrared magnetic aptasensor for Ochratoxin A based on near-infrared upconversion nanoparticles and magnetic nanoparticles.

    PubMed

    Dai, Shaoliang; Wu, Shijia; Duan, Nuo; Wang, Zhouping

    2016-09-01

    A multiplexed, sensitive and specific detection method is highly desirable for the simultaneous detection of several pathogenic bacteria and bio-toxins. In our previous work, multicolor upconversion nanoparticles (UCNPs) via doping with various rare-earth ions to obtain well-separated emission peaks by means of a solvothermal method were synthesized and were successfully applied as luminescence labels in the detection of three pathogenic bacteria. One of the basic achievements of our group has been to establish that the key to increasing the number of simultaneous detection components is the preparation of more UCNPs, the emission peaks of which can be distinguished from each other. According to this vision, NaYF4:Yb0.2, Tm0.02 UCNPs were obtained via a thermal-decomposition protocol, which has a main near-infrared (NIR) UC emission at 804nm under 980nm excitation. The emission peak at 804nm was well-separated from the emission peaks of UCNPs we have reported at 477nm, 542nm, and 660nm. It means both the excitation and the emission of NaYF4:Yb0.2, Tm0.02 UCNPs are located in the NIR spectral range (NIR-to-NIR UC emission), the so-called biological window. This result establishes the basis of achieving simultaneous detection of four components. To confirm the analytical performance of this NaYF4:Yb0.2, Tm0.02 UCNPs, a novel near-infrared magnetic aptasensor for the detection of Ochratoxin A (OTA) was developed using the OTA aptamer-conjugated near-infrared upconversion nanoparticles (apt-UCNPs) and the complementary oligonucleotide-modified magnetic nanoparticles (cDNA-MNPs). The apt-UCNPs and cDNA-MNPs were hybridized to form a poly-network structure of MNP-UCNP nanocomposites. When the target OTA was introduced, the aptamer combined with the priority target and the cDNA-MNPs were replaced. The proposed method achieved a linear range between 0.01 and 100ngmL(-1), with a detection limit as low as 0.005ngmL(-1). Then, we successfully applied this method to measure

  13. Field-testing of a cost-effective mobile-phone based microscope for screening of Schistosoma haematobium infection (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Ceylan Koydemir, Hatice; Bogoch, Isaac I.; Tseng, Derek; Ephraim, Richard K. D.; Duah, Evans; Tee, Joseph; Andrews, Jason R.; Ozcan, Aydogan

    2016-03-01

    Schistosomiasis is a parasitic and neglected tropical disease, and affects <200-million people across the world, with school-aged children disproportionately affected. Here we present field-testing results of a handheld and cost effective smartphone-based microscope in rural Ghana, Africa, for point-of-care diagnosis of S. haematobium infection. In this mobile-phone microscope, a custom-designed 3D printed opto-mechanical attachment (~150g) is placed in contact with the smartphone camera-lens, creating an imaging-system with a half-pitch resolution of ~0.87µm. This unit includes an external lens (also taken from a mobile-phone camera), a sample tray, a z-stage to adjust the focus, two light-emitting-diodes (LEDs) and two diffusers for uniform illumination of the sample. In our field-testing, 60 urine samples, collected from children, were used, where the prevalence of the infection was 72.9%. After concentration of the sample with centrifugation, the sediment was placed on a glass-slide and S. haematobium eggs were first identified/quantified using conventional benchtop microscopy by an expert diagnostician, and then a second expert, blinded to these results, determined the presence/absence of eggs using our mobile-phone microscope. Compared to conventional microscopy, our mobile-phone microscope had a diagnostic sensitivity of 72.1%, specificity of 100%, positive-predictive-value of 100%, and a negative-predictive-value of 57.1%. Furthermore, our mobile-phone platform demonstrated a sensitivity of 65.7% and 100% for low-intensity infections (≤50 eggs/10 mL urine) and high-intensity infections (<50 eggs/10 mL urine), respectively. We believe that this cost-effective and field-portable mobile-phone microscope may play an important role in the diagnosis of schistosomiasis and various other global health challenges.

  14. Infrared thermography for laser-based powder bed fusion additive manufacturing processes

    SciTech Connect

    Moylan, Shawn; Whitenton, Eric; Lane, Brandon; Slotwinski, John

    2014-02-18

    Additive manufacturing (AM) has the potential to revolutionize discrete part manufacturing, but improvements in processing of metallic materials are necessary before AM will see widespread adoption. A better understanding of AM processes, resulting from physics-based modeling as well as direct process metrology, will form the basis for these improvements. Infrared (IR) thermography of AM processes can provide direct process metrology, as well as data necessary for the verification of physics-based models. We review selected works examining how IR thermography was implemented and used in various powder-bed AM processes. This previous work, as well as significant experience at the National Institute of Standards and Technology in temperature measurement and IR thermography for machining processes, shapes our own research in AM process metrology with IR thermography. We discuss our experimental design, as well as plans for future IR measurements of a laser-based powder bed fusion AM process.

  15. Infrared thermography for laser-based powder bed fusion additive manufacturing processes

    NASA Astrophysics Data System (ADS)

    Moylan, Shawn; Whitenton, Eric; Lane, Brandon; Slotwinski, John

    2014-02-01

    Additive manufacturing (AM) has the potential to revolutionize discrete part manufacturing, but improvements in processing of metallic materials are necessary before AM will see widespread adoption. A better understanding of AM processes, resulting from physics-based modeling as well as direct process metrology, will form the basis for these improvements. Infrared (IR) thermography of AM processes can provide direct process metrology, as well as data necessary for the verification of physics-based models. We review selected works examining how IR thermography was implemented and used in various powder-bed AM processes. This previous work, as well as significant experience at the National Institute of Standards and Technology in temperature measurement and IR thermography for machining processes, shapes our own research in AM process metrology with IR thermography. We discuss our experimental design, as well as plans for future IR measurements of a laser-based powder bed fusion AM process.

  16. EMD-Based Symbolic Dynamic Analysis for the Recognition of Human and Nonhuman Pyroelectric Infrared Signals.

    PubMed

    Zhao, Jiaduo; Gong, Weiguo; Tang, Yuzhen; Li, Weihong

    2016-01-01

    In this paper, we propose an effective human and nonhuman pyroelectric infrared (PIR) signal recognition method to reduce PIR detector false alarms. First, using the mathematical model of the PIR detector, we analyze the physical characteristics of the human and nonhuman PIR signals; second, based on the analysis results, we propose an empirical mode decomposition (EMD)-based symbolic dynamic analysis method for the recognition of human and nonhuman PIR signals. In the proposed method, first, we extract the detailed features of a PIR signal into five symbol sequences using an EMD-based symbolization method, then, we generate five feature descriptors for each PIR signal through constructing five probabilistic finite state automata with the symbol sequences. Finally, we use a weighted voting classification strategy to classify the PIR signals with their feature descriptors. Comparative experiments show that the proposed method can effectively classify the human and nonhuman PIR signals and reduce PIR detector's false alarms. PMID:26805837

  17. Hand-held based near-infrared optical imaging devices: a review.

    PubMed

    Erickson, Sarah J; Godavarty, Anuradha

    2009-06-01

    Near-infrared (NIR) optical imaging is a non-invasive and non-ionizing modality that is emerging as a diagnostic/prognostic tool for breast cancer and other applications related to functional brain mapping. In recent years, hand-held based optical imaging devices are developed for clinical translation of the technology, as opposed to the various bulky optical imagers available. Herein, we review the different hand-held based NIR devices developed to date, in terms of the measurement techniques implemented (continuous wave, time or frequency-domain), the imaging methods used, and the specific applications towards which they were applied. The advantages and disadvantages of the different hand-held optical devices are described and also compared with respect to a novel hand-held based device currently developed in our Optical Imaging Laboratory towards three-dimensional tomography studies. PMID:19054704

  18. EMD-Based Symbolic Dynamic Analysis for the Recognition of Human and Nonhuman Pyroelectric Infrared Signals

    PubMed Central

    Zhao, Jiaduo; Gong, Weiguo; Tang, Yuzhen; Li, Weihong

    2016-01-01

    In this paper, we propose an effective human and nonhuman pyroelectric infrared (PIR) signal recognition method to reduce PIR detector false alarms. First, using the mathematical model of the PIR detector, we analyze the physical characteristics of the human and nonhuman PIR signals; second, based on the analysis results, we propose an empirical mode decomposition (EMD)-based symbolic dynamic analysis method for the recognition of human and nonhuman PIR signals. In the proposed method, first, we extract the detailed features of a PIR signal into five symbol sequences using an EMD-based symbolization method, then, we generate five feature descriptors for each PIR signal through constructing five probabilistic finite state automata with the symbol sequences. Finally, we use a weighted voting classification strategy to classify the PIR signals with their feature descriptors. Comparative experiments show that the proposed method can effectively classify the human and nonhuman PIR signals and reduce PIR detector’s false alarms. PMID:26805837

  19. Design and simulation of electrically addressed infrared filtering chip based on cascaded liquid-crystal Fabry-Perot effect for integration application of infrared spectral imaging sensor array

    NASA Astrophysics Data System (ADS)

    Zhang, Huaidong; Fu, Anbang; Zhang, Xinyu; Sang, Hongshi; Xie, Changsheng

    2013-09-01

    A wavelength tunable optical filter based on cascaded Liquid-Crystal Fabry-Perot (LC-FP) cavity with many working units has been proposed and simulated in this paper. By choosing different material and according geometric parameters, we simulated the structure in the wavelength of medium infrared (IR)(3-5μm) and far IR(8-14μm) with the algorithm of thin film matrix equation and iterative finite-difference. Finally, we give the spectrum of the structure under different driving-voltage. Combing this structure with uncooled infrared focal plane array (IRFPA), the image of many spectral bands can be obtained in one picture frame by applying different driving-voltage on each unit. Compared with other design, this structure has the advantages of wide free spectral range (FSR), compact integration, low cost and high stability.

  20. Research on a middle infrared and long infrared dual-band laser based on energy transferring from DF (v) to CO2 (0000)

    NASA Astrophysics Data System (ADS)

    Zhong, Wei; Yuan, Shengfu; Sun, Xu

    2013-05-01

    We propose a continuous wave (CW) middle infrared (MIR) and long infrared (LIR) dual-band laser based on energy transferring from DF (v) to CO2(0000). A total output power of 5W is achieved by the proposed dual-band laser consisted of DF gain medium module (DF module) and DF-CO2 gain medium module (DF-CO2 module). Technologies about the gain peak position, beam qualification are analyzed. The two modules use a common stable resonator and output mirror with nominal transmissivities of 3.5%-5% in the MIR band and 6%-10% in the LIR band. Spectra of dual-band laser are acquired.

  1. Upcoming and Future Missions in the Area of Infrared Astronomy: Spacecraft and Ground-based Observations

    NASA Technical Reports Server (NTRS)

    Sittler, E. C., Jr.

    2004-01-01

    will also be discussed. Improved thermal detectors could have important applications in solar physics, specifically in the detection of far-IR synchrotron emission from energetic electrons in solar flares. For infrared astronomy we have missions like SIRTF and JWST, which will cover the spectral range from near-IR to far-IR in the search and probing of both new and old planetary systems in our galaxy and the measurement of the most distant galaxies of our universe. SIRTF is scheduled to be launched in August 2003, while JWST will be launched next decade. Another mission is TPF, which will use interferometer techniques at infrared wavelengths to search for planetary systems beyond 2010. With regard to ground based telescopes we have, for example, the twin 10 meter Keck telescopes and the IRTF telescope at Mauna Kea. The Keck telescopes are presently using interferometer techniques. Over the next several decades there are plans for 50 meter to 200 meter telescopes providing near-IR to far-IR measurements with the eventual plan to combine all telescopes using interferometer techniques to provide unprecedented spectral-spatial resolution and sensitivity.

  2. UV-laser-based microscopic dissection of tree rings - a novel sampling tool for δ(13) C and δ(18) O studies.

    PubMed

    Schollaen, Karina; Heinrich, Ingo; Helle, Gerhard

    2014-02-01

    UV-laser-based microscopic systems were utilized to dissect and sample organic tissue for stable isotope measurements from thin wood cross-sections. We tested UV-laser-based microscopic tissue dissection in practice for high-resolution isotopic analyses (δ(13) C/δ(18) O) on thin cross-sections from different tree species. The method allows serial isolation of tissue of any shape and from millimetre down to micrometre scales. On-screen pre-defined areas of interest were automatically dissected and collected for mass spectrometric analysis. Three examples of high-resolution isotopic analyses revealed that: in comparison to δ(13) C of xylem cells, woody ray parenchyma of deciduous trees have the same year-to-year variability, but reveal offsets that are opposite in sign depending on whether wholewood or cellulose is considered; high-resolution tree-ring δ(18) O profiles of Indonesian teak reflect monsoonal rainfall patterns and are sensitive to rainfall extremes caused by ENSO; and seasonal moisture signals in intra-tree-ring δ(18) O of white pine are weighted by nonlinear intra-annual growth dynamics. The applications demonstrate that the use of UV-laser-based microscopic dissection allows for sampling plant tissue at ultrahigh resolution and unprecedented precision. This new technique facilitates sampling for stable isotope analysis of anatomical plant traits like combined tree eco-physiological, wood anatomical and dendroclimatological studies. PMID:24219751

  3. Miniature in vivo MEMS-based line-scanned dual-axis confocal microscope for point-of-care pathology

    PubMed Central

    Yin, C.; Glaser, A.K.; Leigh, S. Y.; Chen, Y.; Wei, L.; Pillai, P. C. S.; Rosenberg, M. C.; Abeytunge, S.; Peterson, G.; Glazowski, C.; Sanai, N.; Mandella, M. J.; Rajadhyaksha, M.; Liu, J. T. C.

    2016-01-01

    There is a need for miniature optical-sectioning microscopes to enable in vivo interrogation of tissues as a real-time and noninvasive alternative to gold-standard histopathology. Such devices could have a transformative impact for the early detection of cancer as well as for guiding tumor-resection procedures. Miniature confocal microscopes have been developed by various researchers and corporations to enable optical sectioning of highly scattering tissues, all of which have necessitated various trade-offs in size, speed, depth selectivity, field of view, resolution, image contrast, and sensitivity. In this study, a miniature line-scanned (LS) dual-axis confocal (DAC) microscope, with a 12-mm diameter distal tip, has been developed for clinical point-of-care pathology. The dual-axis architecture has demonstrated an advantage over the conventional single-axis confocal configuration for reducing background noise from out-of-focus and multiply scattered light. The use of line scanning enables fast frame rates (16 frames/sec is demonstrated here, but faster rates are possible), which mitigates motion artifacts of a hand-held device during clinical use. We have developed a method to actively align the illumination and collection beams in a DAC microscope through the use of a pair of rotatable alignment mirrors. Incorporation of a custom objective lens, with a small form factor for in vivo clinical use, enables our device to achieve an optical-sectioning thickness and lateral resolution of 2.0 and 1.1 microns respectively. Validation measurements with reflective targets, as well as in vivo and ex vivo images of tissues, demonstrate the clinical potential of this high-speed optical-sectioning microscopy device. PMID:26977337

  4. [Validation of HJ-1B thermal infrared channels onboard radiometric calibration based on spectral response differences].

    PubMed

    Liu, Li; Fu, Qiao-yan; Shi, Ting-ting; Wang, Ai-chun; Zhang, Xue-wen

    2014-08-01

    Since HJ-1B was launched, 7 sets of blackbody data have been used to calculate onboard calibration coefficients, but the research work on the validation of coefficients is rare. According to the onboard calibration principle, calibration coefficients of HJ-1B thermal infrared channel on Sep 14th, 2009 were calculated with the half-width, moments and look-up table methods. MODIS was selected for the reference sensor, and algorithms of spectral match were improved between the HJ-1B thermal infrared channel and MODIS 31, 32 channels based on the spectral response divergence. The relationship of top of atmosphere (TOA) radiance between the remote sensors was calculated, based on which the surface leaving brightness temperature was calculated by Planck function to validate the brightness temperature calculated through the onboard calibration coefficients. The equivalent brightness temperature calculated by spectral response divergence method is 285.97 K, and the inversion brightness temperature calculated by half-width, moments and look-up table methods is 288.77, 274.52 and 285.97 K respectively. The difference between the inversion brightness temperature and the equivalent brightness temperature is 2.8, -11.46 and 0.02 K, respectively, which demonstrate that onboard calibration coefficients calculated by the look-up table method has better precision and feasibility. PMID:25508743

  5. [Validation of HJ-1B thermal infrared channels onboard radiometric calibration based on spectral response differences].

    PubMed

    Liu, Li; Fu, Qiao-yan; Shi, Ting-ting; Wang, Ai-chun; Zhang, Xue-wen

    2014-08-01

    Since HJ-1B was launched, 7 sets of blackbody data have been used to calculate onboard calibration coefficients, but the research work on the validation of coefficients is rare. According to the onboard calibration principle, calibration coefficients of HJ-1B thermal infrared channel on Sep 14th, 2009 were calculated with the half-width, moments and look-up table methods. MODIS was selected for the reference sensor, and algorithms of spectral match were improved between the HJ-1B thermal infrared channel and MODIS 31, 32 channels based on the spectral response divergence. The relationship of top of atmosphere (TOA) radiance between the remote sensors was calculated, based on which the surface leaving brightness temperature was calculated by Planck function to validate the brightness temperature calculated through the onboard calibration coefficients. The equivalent brightness temperature calculated by spectral response divergence method is 285.97 K, and the inversion brightness temperature calculated by half-width, moments and look-up table methods is 288.77, 274.52 and 285.97 K respectively. The difference between the inversion brightness temperature and the equivalent brightness temperature is 2.8, -11.46 and 0.02 K, respectively, which demonstrate that onboard calibration coefficients calculated by the look-up table method has better precision and feasibility. PMID:25474964

  6. Research for fluid impurity detection based on ANN and infrared spectrum analysis technology

    NASA Astrophysics Data System (ADS)

    Ma, Huiping; Yuan, Feng

    2011-08-01

    A series of economic losses is caused by the biofilm of water pipe in industrial real water systems. Combined optical fiber self-relative technology with infrared spectrum analysis technology, real time detection technique for forming thickness and ingredient is put forward in the paper, which provides technical support and reliable data for analyzing biofouling influencing factors, contaminant separation and warning. Schematic diagram of biofouling detection is presented. Compensation technology based on radial basis function (RBF) neural network and learning algorithm are studied in order to solve the problem of measurement precision and range. Biofouling forming and optical characteristics in industrial real water systems are researched and standard specimen collection is set up. Correcting model explaining quantitatively relation between substance ingredient content and infrared spectrum based on partial least squares (PLS) method. A new method is provided for the research on biofouling in real water system, which can be used in other fields such as mining, environment protection, medical treatment and transportation of oil, gas and water.

  7. Thermal Lens Microscope

    NASA Astrophysics Data System (ADS)

    Uchiyama, Kenji; Hibara, Akihide; Kimura, Hiroko; Sawada, Tsuguo; Kitamori, Takehiko

    2000-09-01

    We developed a novel laser microscope based on the thermal lens effect induced by a coaxial beam comprised of excitation and probe beams. The signal generation mechanism was confirmed to be an authentic thermal lens effect from the measurement of signal and phase dependences on optical configurations between the sample and the probe beam focus, and therefore, the thermal lens effect theory could be applied. Two-point spatial resolution was determined by the spot size of the excitation beam, not by the thermal diffusion length. Sensitivity was quite high, and the detection ability, evaluated using a submicron microparticle containing dye molecules, was 0.8 zmol/μm2, hence a distribution image of trace chemical species could be obtained quantitatively. In addition, analytes are not restricted to fluorescent species, therefore, the thermal lens microscope is a promising analytical microscope. A two-dimensional image of a histamine molecule distribution, which was produced in mast cells at the femtomole level in a human nasal mucous polyp, was obtained.

  8. Virtual pinhole confocal microscope

    SciTech Connect

    George, J.S.; Rector, D.M.; Ranken, D.M.; Peterson, B.; Kesteron, J.

    1999-06-01

    Scanned confocal microscopes enhance imaging capabilities, providing improved contrast and image resolution in 3-D, but existing systems have significant technical shortcomings and are expensive. Researchers at Los Alamos National Laboratory have developed a novel approach--virtual pinhole confocal microscopy--that uses state of the art illumination, detection, and data processing technologies to produce an imager with a number of advantages: reduced cost, faster imaging, improved efficiency and sensitivity, improved reliability and much greater flexibility. Work at Los Alamos demonstrated proof of principle; prototype hardware and software have been used to demonstrate technical feasibility of several implementation strategies. The system uses high performance illumination, patterned in time and space. The authors have built functional confocal imagers using video display technologies (LCD or DLP) and novel scanner based on a micro-lens array. They have developed a prototype system for high performance data acquisition and processing, designed to support realtime confocal imaging. They have developed algorithms to reconstruct confocal images from a time series of spatially sub-sampled images; software development remains an area of active development. These advances allow the collection of high quality confocal images (in fluorescence, reflectance and transmission modes) with equipment that can inexpensively retrofit to existing microscopes. Planned future extensions to these technologies will significantly enhance capabilities for microscopic imaging in a variety of applications, including confocal endoscopy, and confocal spectral imaging.

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

    NASA Astrophysics Data System (ADS)

    Zhang, Qiong; Maldague, Xavier

    2016-01-01

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

  10. High efficiency near diffraction-limited mid-infrared flat lenses based on metasurface reflectarrays.

    PubMed

    Zhang, Shuyan; Kim, Myoung-Hwan; Aieta, Francesco; She, Alan; Mansuripur, Tobias; Gabay, Ilan; Khorasaninejad, Mohammadreza; Rousso, David; Wang, Xiaojun; Troccoli, Mariano; Yu, Nanfang; Capasso, Federico

    2016-08-01

    We report the first demonstration of a mid-IR reflection-based flat lens with high efficiency and near diffraction-limited focusing. Focusing efficiency as high as 80%, in good agreement with simulations (83%), has been achieved at 45° incidence angle at λ = 4.6 μm. The off-axis geometry considerably simplifies the optical arrangement compared to the common geometry of normal incidence in reflection mode which requires beam splitters. Simulations show that the effects of incidence angle are small compared to parabolic mirrors with the same NA. The use of single-step photolithography allows large scale fabrication. Such a device is important in the development of compact telescopes, microscopes, and spectroscopic designs. PMID:27505769

  11. Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films

    NASA Astrophysics Data System (ADS)

    Kocer, Hasan; Butun, Serkan; Palacios, Edgar; Liu, Zizhuo; Tongay, Sefaattin; Fu, Deyi; Wang, Kevin; Wu, Junqiao; Aydin, Koray

    2015-08-01

    Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.

  12. A near-Infrared Fluorescent Chemodosimeter for Ratiometric Detecting Fluoride Based on Desilylation Reaction.

    PubMed

    Xie, Puhui; Guo, Fengqi; Gao, Guangqin; Fan, Wei; Yang, Guoyu; Xie, Lixia

    2016-09-01

    A new chemodosimeter based on dicyanomethylene-4H-chromene chromophore (probe 1) was developed as a ratiometric fluorescent probe in near-infrared range for F(-) with good selectivity in acetonitrile. Probe 1 could be used to directly visualize F(-) by the naked eye and showed more than 621-fold fluorescence enhancement at 715 nm upon reaction with F(-) upon excitation at 625 nm. The recognition of probe 1 to fluoride was featured by F(-)-induced red-shifts of both absorption (185 nm) and fluorescence peaks (132 nm) based on internal charge transfer (ICT) in acetonitrile. The desilylation reaction of 1 by F(-) was proposed for its dual absorption and emission ratiometric detection of fluoride. PMID:27365125

  13. Physics Based Modeling and Rendering of Vegetation in the Thermal Infrared

    NASA Technical Reports Server (NTRS)

    Smith, J. A.; Ballard, J. R., Jr.

    1999-01-01

    We outline a procedure for rendering physically-based thermal infrared images of simple vegetation scenes. Our approach incorporates the biophysical processes that affect the temperature distribution of the elements within a scene. Computer graphics plays a key role in two respects. First, in computing the distribution of scene shaded and sunlit facets and, second, in the final image rendering once the temperatures of all the elements in the scene have been computed. We illustrate our approach for a simple corn scene where the three-dimensional geometry is constructed based on measured morphological attributes of the row crop. Statistical methods are used to construct a representation of the scene in agreement with the measured characteristics. Our results are quite good. The rendered images exhibit realistic behavior in directional properties as a function of view and sun angle. The root-mean-square error in measured versus predicted brightness temperatures for the scene was 2.1 deg C.

  14. [Correction method for infrared spectral emissivity measurement system based on integrating sphere reflectometer].

    PubMed

    Zhang, Yu-Feng; Dai, Jing-Min; Zhang, Yu; Pan, Wei-Dong; Zhang, Lei

    2013-08-01

    In view of the influence of non-ideal reference standard on spectral emissivity measurement, by analyzing the principle of infrared emissivity measurement system based on integrating sphere reflectometer, a calibration method suitable for measuring spectral emissivity system using the reflection measurement was proposed. By fitting a spectral reflectance curve of the reference standard sample to the given reflectance data, the correction coefficient of measurement system was computed. Then the output voltage curve of reference standard sample was corrected by this coefficient. The system error caused by the imperfection of reference standard was eliminated. The correction method was applied to the spectral emissivity measurement system based on integrating sphere reflectometer. The results measured by the corrected system and the results measured by energy comparison measurement were compared to verify the feasibility and effectivity of this correction method in improving the accuracy of spectral emissivity measurement. PMID:24159891

  15. Research of Rice-Quality Based on Computer Vision and Near Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Chang, Ruokui; Zhang, Weiyu; Cui, Jing; Wang, Yuanhong; Wei, Yong; Liu, Yuan

    A rapid and nondestructive way to measure protein and amylose content of rice was put forward based on near infrared(NIR) spectral technology. The NIR spectra were acquired from 13 varieties of rice with the wavelength from700 to 1100nm. The objectives of the present study were to establish forecasting model to find out the relationship between the absorbance of the spectrum and the main components of rice. By using the machine vision-based method, the rice appearance quality can be studied. On the basis of the evaluation criteria, 13 different kinds of rice were classified. And according to the usage of neural network, the detection model was established, so it can lay the foundation for the prediction grade of the unknown kinds of rice in the future.

  16. About the scheme of the infrared FEL system for the accelerator based on HF wells

    SciTech Connect

    Kabanov, V.S.; Dzergach, A.I.

    1995-12-31

    Accelerators, based on localization of plasmoids in the HF wells (RF traps) of the axially-symmetric electromagnetic field E {sub omn} in an oversized (m,n>>1) resonant system, can give accelerating gradients {approximately}100 kV/{lambda}, e.g. 10 GV/m if {lambda}=10 {mu}m. One of possible variants of HF feeding for these accelerators is based on using the powerful infrared FEL System with 2 frequencies. The corresponding FEL`s may be similar to the Los Alamos compact Advanced FEL ({lambda}{sub 1,2}{approximately}10 pm, e-beam energy {approximately}15 MeV, e-beam current {approximately}100 A). Their power is defined mainly by the HF losses in the resonant system of the supposed accelerator.

  17. Design of readout circuit for microcantilever-based ripple uncooled infrared focal plane arrays

    NASA Astrophysics Data System (ADS)

    Cao, Junmin; Chen, Zhongjian; Lu, Wengao; Zhang, Yacong; Lei, Ke; Zhao, Baoying

    2009-07-01

    A readout integrated circuit (ROIC) for uncooled microcantilever infrared focal plane arrays (IRFPAs) based on capacitive readout is proposed. The ROIC is optimized according to noise modeling and analysis to reduce noise. An experimental chip of 16×16 FPAs readout circuit has been designed and fabricated using 0.35um CMOS technology. The measurement results showed that the power dissipation is 16.5mW from a 5V supply voltage at 50Hz frame rate, the linearity is 99.2% at the typical mode; the uniformity is larger than 97% and the equivalent noise charge (ENC) is below 150e. It is believed that the ROIC has a great potential in the applications of large-scale micro-cantilever-based uncooled IRFPAs.

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

    NASA Astrophysics Data System (ADS)

    Yu, Jiajia; He, Yong

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

  19. Tunable broadband optical field enhancement in graphene-based slot waveguide at infrared frequencies.

    PubMed

    Lu, Wanli

    2016-07-01

    Tunable broadband optical field enhancements are demonstrated for graphene-based nanoscale slot waveguides, and the extremely strong field intensity inside the slot region is produced based on the ultrahigh effective mode index. Analytic formulas are obtained to reveal the dependence of enhanced optical fields and effective mode index on the gap distance, the Fermi energy, the width of nanoribbons, and the background medium. We show that most of the optical field is concentrated within the slot regions with the normalized power about up to 86%, and the averaged optical field intensity reaches 104  μm-2 for the slot waveguide with a 3 nm gap distance and 50 nm width. Meanwhile, the optical field enhancement effect is broadband at infrared frequencies and controlled by Fermi energy via bias electrical voltage for graphene. PMID:27409196

  20. Infrared ground-based astronomy with the Hughes 256 X 256 PtSi array

    NASA Technical Reports Server (NTRS)

    Fowler, A.; Joyce, R.; Gatley, I.; Gates, J.; Herring, J.

    1989-01-01

    It is shown that large format PtSi Schottky diode infrared arrays, the Hughes 256 X 256 hybrid Schottky array in particular, are competitive alternatives to the smaller format photovoltaic arrays for ground-based astronomy. The modest quantum efficiency of the PtSi compared to the photovoltaic devices is more than compensated for by the larger format. The use of hybrid technology yields effective fill factors of nearly 100 percent, and the low dark current, noise, excellent imaging characteristics, cost, and solid nitrogen operating temperature add to the effectiveness of this array for ground-based imaging. In addition to discussing the characteristics of this array, researchers present laboratory test data and astronomical results achieved at Kitt Peak.

  1. Calibration diagnostic and updating strategy based on quantitative modeling of near-infrared spectral residuals.

    PubMed

    Yu, Hua; Small, Gary W

    2015-02-01

    A diagnostic and updating strategy is explored for multivariate calibrations based on near-infrared spectroscopy. For use with calibration models derived from spectral fitting or decomposition techniques, the proposed method constructs models that relate the residual concentrations remaining after a prediction to the residual spectra remaining after the information associated with the calibration model has been extracted. This residual modeling approach is evaluated for use with partial least-squares (PLS) models for predicting physiological levels of glucose in a simulated biological matrix. Residual models are constructed with both PLS and a hybrid technique based on the use of PLS scores as inputs to support vector regression. Calibration and residual models are built with both absorbance and single-beam data collected over 416 days. Effective models for the spectral residuals are built with both types of data and demonstrate the ability to diagnose and correct deviations in performance of the calibration model with time. PMID:25473807

  2. Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films

    PubMed Central

    Kocer, Hasan; Butun, Serkan; Palacios, Edgar; Liu, Zizhuo; Tongay, Sefaattin; Fu, Deyi; Wang, Kevin; Wu, Junqiao; Aydin, Koray

    2015-01-01

    Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing. PMID:26294085

  3. Neonatal non-contact respiratory monitoring based on real-time infrared thermography

    PubMed Central

    2011-01-01

    Background Monitoring of vital parameters is an important topic in neonatal daily care. Progress in computational intelligence and medical sensors has facilitated the development of smart bedside monitors that can integrate multiple parameters into a single monitoring system. This paper describes non-contact monitoring of neonatal vital signals based on infrared thermography as a new biomedical engineering application. One signal of clinical interest is the spontaneous respiration rate of the neonate. It will be shown that the respiration rate of neonates can be monitored based on analysis of the anterior naris (nostrils) temperature profile associated with the inspiration and expiration phases successively. Objective The aim of this study is to develop and investigate a new non-contact respiration monitoring modality for neonatal intensive care unit (NICU) using infrared thermography imaging. This development includes subsequent image processing (region of interest (ROI) detection) and optimization. Moreover, it includes further optimization of this non-contact respiration monitoring to be considered as physiological measurement inside NICU wards. Results Continuous wavelet transformation based on Debauches wavelet function was applied to detect the breathing signal within an image stream. Respiration was successfully monitored based on a 0.3°C to 0.5°C temperature difference between the inspiration and expiration phases. Conclusions Although this method has been applied to adults before, this is the first time it was used in a newborn infant population inside the neonatal intensive care unit (NICU). The promising results suggest to include this technology into advanced NICU monitors. PMID:22243660

  4. A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment.

    PubMed

    Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi

    2016-01-01

    This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments. PMID:27589755

  5. Research on the algorithm of infrared target detection based on the frame difference and background subtraction method

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Zhao, Yuejin; Liu, Ming; Dong, Liquan; Hui, Mei; Liu, Xiaohua; Wu, Yijian

    2015-09-01

    As an important branch of infrared imaging technology, infrared target tracking and detection has a very important scientific value and a wide range of applications in both military and civilian areas. For the infrared image which is characterized by low SNR and serious disturbance of background noise, an innovative and effective target detection algorithm is proposed in this paper, according to the correlation of moving target frame-to-frame and the irrelevance of noise in sequential images based on OpenCV. Firstly, since the temporal differencing and background subtraction are very complementary, we use a combined detection method of frame difference and background subtraction which is based on adaptive background updating. Results indicate that it is simple and can extract the foreground moving target from the video sequence stably. For the background updating mechanism continuously updating each pixel, we can detect the infrared moving target more accurately. It paves the way for eventually realizing real-time infrared target detection and tracking, when transplanting the algorithms on OpenCV to the DSP platform. Afterwards, we use the optimal thresholding arithmetic to segment image. It transforms the gray images to black-white images in order to provide a better condition for the image sequences detection. Finally, according to the relevance of moving objects between different frames and mathematical morphology processing, we can eliminate noise, decrease the area, and smooth region boundaries. Experimental results proves that our algorithm precisely achieve the purpose of rapid detection of small infrared target.

  6. Novel far infrared imaging sensor based on the use of titanium-nickel shape memory alloys

    NASA Astrophysics Data System (ADS)

    Ho, Ho-Pui; Chung, Jonathan C. Y.; Ng, Ki-Cheong; Cheng, K. L.; Wu, Shu-Yuen

    2002-11-01

    In this paper we describe a novel imaging sensor design1 that uses the thermo-mechanical properties of nickel-titanium (NiTi) shape memory alloys (SMAs) for detecting far infrared radiation (FIR). A thin NiTi SMA cantilever is coated with a FIR absorbing layer on one surface, while the other is coated with a highly reflecting metallic layers such as gold. Upon absorption of FIR, the temperature of the cantilever changes. This causes the tilt angle of the cantilever to change as well. The deflection is very large if the temperature change coincides with the temperature range of the phase transformation of the NiTi SMA. The detection of the mechanical movements in the cantilever is achieved by illuminating the reflective side using a visible laser beam. A Michelson interferometer is used to covert the reflected light into optical modulation. In doing this, very small displacement in the cantilever can be visualized as laser intensity variation. A single element device has been fabricated for this purpose and our initial experimental results have demonstrated the successful detection of FIR. An estimation of angular deflection per unit change of temperature suggests that our approach can offer sensitivity higher than the reported design based on the use of bi-material strips. We envisage that a two-dimensional array of such devices can lead to the possibility of realizing a practical low-cost infrared imaging device operating under room temperature conditions.

  7. Design and implement of infrared small target real-time detection system based on pipeline technology

    NASA Astrophysics Data System (ADS)

    Sun, Lihui; Wang, Yongzhong; He, Yongqiang

    2007-01-01

    The detection for motive small target in infrared image sequence has become a hot topic nowadays. Background suppress algorithm based on minim gradient median filter and temporal recursion target detection algorithm are introduced. On the basis of contents previously mentioned, a four stages pipeline structure infrared small target detection process system, which aims at characters of algorithm complexity, large amounts of data to process, high frame frequency and exigent real-time character in this kind of application, is designed and implemented. The logical structure of the system was introduced and the function and signals flows are programmed. The system is composed of two FPGA chips and two DSP chips of TI. According to the function of each part, the system is divided into image preprocess stage, target detection stage, track relation stage and image output stage. The experiment of running algorithms on the system presented in this paper proved that the system could meet acquisition and process of 50Hz 240x320 digital image and the system could real time detect small target with a signal-noise ratio more than 3 reliably. The system achieves the characters of large amount of memory, high real-time processing, excellent extension and favorable interactive interface.

  8. Investigation of acousto-optic properties of tellurium-based glasses for infrared applications

    NASA Astrophysics Data System (ADS)

    Voloshinov, V. B.; Gupta, N.; Kulakova, L. A.; Khorkin, V. S.; Melekh, B. T.; Knyazev, G. A.

    2016-02-01

    We examined the physical properties of infrared optical glasses composed of tellurium, germanium, selenium, sulfur and silicon. In particular, we measured optical, acoustic and photoelastic parameters of the following alloy compounds: germanium-selenium-tellurium (Ge-Se-Te), germanium-selenium-sulfur-tellurium (Ge-Se-S-Te), germanium-silicon-tellurium (Ge-Si-Te) and silicon-tellurium (Si-Te). Like single-crystal tellurium, the glasses demonstrate good acousto-optic (AO) diffraction efficiency and have reasonable optical transparency in a wide spectral region covering wavelengths from 1.5 to 20 μm. The optical, acoustic and photoelastic properties of the tellurium-based compounds were measured using infrared lamp sources of radiation as well as He-Ne and CO2 lasers. In this paper, we report on the optical, acoustic and photoelastic parameters of a selection of these compounds and discuss the advantages and disadvantages of using these glasses for AO device applications. We also present the measured characteristics of an AO cell fabricated in a Si20Te80 glass material which exhibited high optical uniformity and long-term chemical stability.

  9. [Based on Trigger Sampling Method and Phase Correction of Infrared Spectrum Measurement Applications].

    PubMed

    Li, Yan; Gao, Min-guang; Xu, Liang; Li, Sheng; Li, Xiang-xian; Ye, Shu-bin; Liu, Jian-guo

    2015-07-01

    Fourier transform infrared spectrometer can be realized in high temperature flue gas multicomponent measurement at the same time, has wide application prospects in the field. And one of the important factors to determine the success of application, lies in the measuring system of infrared interference figure sampling phase error control. This paper discusses the main-reasons of the appearance of phase error in the system, through the analysis of Helium-neon laser interference signal zero uniformity, illustrates the produce phase error is the main reason of the laser signal and reference signal phase difference. At the meantime, the quantitative analysis of the phase error influence on instrument signal to noise ratio (SNR), also the Mertz phase correction method for the instrument improves the thousands of times of the original signal to noise ratio. And the related experiment, the experimental results show that the system based on the interference figure sampling method satisfy the needs of high temperature flue gas measurements. PMID:26717778

  10. Adaptive non-uniformity correction method based on temperature for infrared detector array

    NASA Astrophysics Data System (ADS)

    Zhang, Zhijie; Yue, Song; Hong, Pu; Jia, Guowei; Lei, Bo

    2013-09-01

    The existence of non-uniformities in the responsitivity of the element array is a severe problem typical to common infrared detector. These non-uniformities result in a "curtain'' like fixed pattern noises (FPN) that appear in the image. Some random noise can be restrained by the method kind of equalization method. But the fixed pattern noise can only be removed by .non uniformity correction method. The produce of non uniformities of detector array is the combined action of infrared detector array, readout circuit, semiconductor device performance, the amplifier circuit and optical system. Conventional linear correction techniques require costly recalibration due to the drift of the detector or changes in temperature. Therefore, an adaptive non-uniformity method is needed to solve this problem. A lot factors including detectors and environment conditions variety are considered to analyze and conduct the cause of detector drift. Several experiments are designed to verify the guess. Based on the experiments, an adaptive non-uniformity correction method is put forward in this paper. The strength of this method lies in its simplicity and low computational complexity. Extensive experimental results demonstrate the disadvantage of traditional non-uniformity correct method is conquered by the proposed scheme.

  11. Discrimination between two different grades of human glioma based on blood vessel infrared spectral imaging.

    PubMed

    Wehbe, Katia; Forfar, Isabelle; Eimer, Sandrine; Cinque, Gianfelice

    2015-09-01

    Gliomas are brain tumours classified into four grades with increasing malignancy from I to IV. The development and the progression of malignant glioma largely depend on the tumour vascularization. Due to their tissue heterogeneity, glioma cases can be difficult to classify into a specific grade using the gold standard of histological observation, hence the need to base classification on a quantitative and reliable analytical method for accurately grading the disease. Previous works focused specifically on vascularization study by Fourier transform infrared (FTIR) spectroscopy, proving this method to be a way forward to detect biochemical changes in the tumour tissue not detectable by visual techniques. In this project, we employed FTIR imaging using a focal plane array (FPA) detector and globar source to analyse large areas of glioma tumour tissue sections via molecular fingerprinting in view of helping to define markers of the tumour grade. Unsupervised multivariate analysis (hierarchical cluster analysis and principal component analysis) of blood vessel spectral data, retrieved from the FPA images, revealed the fine structure of the borderline between two areas identified by a pathologist as grades III and IV. Spectroscopic indicators are found capable of discriminating different areas in the tumour tissue and are proposed as biomolecular markers for potential future use of grading gliomas. Graphical Abstract Infrared imaging of glioma blood vessels provides a means to revise the pathologists' line of demarcation separating grade III (GIII) from grade IV (GIV) parts. PMID:26168973

  12. Broadband on-chip near-infrared spectroscopy based on a plasmonic grating filter array.

    PubMed

    Li, Erwen; Chong, Xinyuan; Ren, Fanghui; Wang, Alan X

    2016-05-01

    We demonstrate an ultra-compact, broadband on-chip near-infrared (NIR) spectroscopy system based on a narrow-band plasmonic filter array. The entire filter array, consisting of 28 individual subwavelength metallic gratings, was monolithically integrated in a thin gold film on a quartz substrate, covering a 270 nm spectra from 1510 nm to 1780 nm. In order to achieve a high spectral resolution, extremely narrow slits are created for the gratings with a polymer waveguide layer on top, generating narrow-band guided-mode resonances through coupling with the surface-plasmon resonances of the metallic gratings. Experimental results show that the transmission bands of the filter array have full width at half-maximum of only 7 nm-13 nm, which is sufficient for NIR spectroscopy. The NIR absorption spectroscopy of xylene using the on-chip plasmonic filter array matches very well with the results from conventional Fourier transform infrared spectroscopy, which proves the great potential for NIR sensing applications. PMID:27128037

  13. A Near-Infrared Spectrometer Based on Novel Grating Light Modulators

    PubMed Central

    Wei, Wei; Huang, Shanglian; Wang, Ning; Jin, Zhu; Zhang, Jie; Chen, Weimin

    2009-01-01

    A near-infrared spectrometer based on novel MOEMS grating light modulators is proposed. The spectrum detection method that combines a grating light modulator array with a single near-infrared detector has been applied. Firstly, optics theory has been used to analyze the essential principles of the proposed spectroscopic sensor. Secondly, the grating light modulators have been designed and fabricated by micro-machining technology. Finally, the principles of this spectroscopic sensor have been validated and its key parameters have been tested by experiments. The result shows that the spectral resolution is better than 10 nm, the wavelength deviation is less than 1 nm, the deviation of the intensity of peak wavelength is no more than 0.5%, the driving voltage of grating light modulators array device is below 25 V and the response frequency of it is about 5 kHz. With low cost, satisfactory precision, portability and other advantages, the spectrometer should find potential applications in food safety and quality monitoring, pharmaceutical identification and agriculture product quality classification. PMID:22574065

  14. Cooled and uncooled infrared detectors based on yttrium barium copper oxide

    NASA Astrophysics Data System (ADS)

    Sobolewski, Roman; Butler, Donald P.; Celik-Butler, Zeynep

    2001-03-01

    We review performance and physical characteristics of yttrium barium copper oxide (YBCO) compound as an infrared (IR) photodetector. YBCO has been used as the IR detector material in both superconducting (oxygen-rich) and semiconducting (oxygen-depleted) phases. YBCO in its crystalline, Yba2Cu3O6+x phase with x>0.95 is a high-temperature superconducting material with the superconducting transition Tcapproximately equals 90K. The superconducting YBCOIR detectors operate as either nonequilibrium (quantum) or bolometric (thermal) devices. The nonequilibrium devices are characterized by very short, single-picosecond photoresponse times and are expected to find applications in optoelectronics and imaging, as well as ultrafast optical-to-electrical transducers for digital input applications. The bolometric mechanism results in relatively slow but very sensitive detectors with possible applications in astronomy. In addition to superconducting IR sensors, interest in uncooled YBCO devices is growing very rapidly. Despite somewhat lower sensitivity and significantly reduced speed of response, as compared to the superconducting counterpartners, the uncooled IR detectors are characterized by much lower operating cost and weight due to lack of cooling cryogens and are compatible with existing silicon-based processing and fabrication. The last point is of paramount importance if the IR-sensitive pixels are to be integrated with CMOS read-out circuitry for monolithic focal plane arrays and infrared cameras. Amorphous uncooled YBCO photodetectors operate as either photoconductive bolometers of unbiased pyroelectric devices.

  15. A regional density distribution based wide dynamic range algorithm for infrared camera systems

    NASA Astrophysics Data System (ADS)

    Park, Gyuhee; Kim, Yongsung; Joung, Shichang; Shin, Sanghoon

    2014-10-01

    Forward Looking InfraRed (FLIR) imaging system has been widely used for both military and civilian purposes. Military applications include target acquisition and tracking, night vision system. Civilian applications include thermal efficiency analysis, short-ranged wireless communication, weather forecasting and other various applications. The dynamic range of FLIR imaging system is larger than one of commercial display. Generally, auto gain controlling and contrast enhancement algorithm are applied to FLIR imaging system. In IR imaging system, histogram equalization and plateau equalization is generally used for contrast enhancement. However, they have no solution about the excessive enhancing when luminance histogram has been distributed in specific narrow region. In this paper, we proposed a Regional Density Distribution based Wide Dynamic Range algorithm for Infrared Camera Systems. Depending on the way of implementation, the result of WDR is quite different. Our approach is single frame type WDR algorithm for enhancing the contrast of both dark and white detail without loss of bins of histogram with real-time processing. The significant change in luminance caused by conventional contrast enhancement methods may introduce luminance saturation and failure in object tracking. Proposed method guarantees both the effective enhancing in contrast and successive object tracking. Moreover, since proposed method does not using multiple images on WDR, computation complexity might be significantly reduced in software / hardware implementation. The experimental results show that proposed method has better performance compared with conventional Contrast enhancement methods.

  16. Processing ground-based near-infrared imagery of space shuttle re-entries

    NASA Astrophysics Data System (ADS)

    Spisz, Thomas S.; Taylor, Jeff C.; Kennerly, Stephen W.; Osei-Wusu, Kwame; Gibson, David M.; Horvath, Thomas J.; Zalameda, Joseph N.; Kerns, Robert V.; Shea, Edward J.; Mercer, C. David; Schwartz, Richard J.; Dantowitz, Ronald F.; Kozubal, Marek J.

    2012-06-01

    Ground-based high-resolution, calibrated, near-infrared (NIR) imagery of the Space Shuttle STS-134 Endeavour during reentry has been obtained as part of NASA's HYTHIRM (Hypersonic Thermodynamic InfraRed Measurements) project. The long-range optical sensor package called MARS (Mobile Aerospace Reconnaissance System) was positioned in advance to acquire and track part of the shuttle re-entry. Imagery was acquired during a few minutes, with the best imagery being processed when the shuttle was at 133 kft at Mach 5.8. This paper describes the processing of the NIR imagery, building upon earlier work from the airborne imagery collections of several prior shuttle missions. Our goal is to calculate the temperature distribution of the shuttle's bottom surface as accurately as possible, considering both random and systematic errors, while maintaining all physical features in the imagery, especially local intensity variations. The processing areas described are: 1) radiometric calibration, 2) improvement of image quality, 3) atmospheric compensation, and 4) conversion to temperature. The computed temperature image will be shown, as well as comparisons with thermocouples at different positions on the shuttle. A discussion of the uncertainties of the temperature estimates using the NIR imagery is also given.

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

    NASA Astrophysics Data System (ADS)

    Zhao, Bingjie; Gao, Wei; Song, Zongxi

    2013-09-01

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

  18. Small moving infrared space target tracking algorithm based on probabilistic data association filter

    NASA Astrophysics Data System (ADS)

    Li, Zhengzhou; Chen, Jing; Gu, Yuanshan; Tang, Lan; Dai, Zhen; Fu, Hongxia; Li, Ruzhang; Liu, Changju; Jin, Gang

    2014-03-01

    Numerous false alarms for low signal-to-noise ratio (SNR) would seriously debase the performance for infrared low observable (LO) space target tracking. Due to the motion (i.e. azimuth, elevation and their derivative velocity), amplitude and size of infrared target are almost invariable and highly correlative, a multi-feature association approach based on probabilistic data association (PDA) is presented to track target in this paper. Firstly, the motion, amplitude and size of target are modeled as stationary random signal afforded Gaussian distribution. The probability of motion, amplitude and size of measurement originated as the target of interest is then estimated by Gaussian distribution, and that of false alarm is distributed uniformly. Subsequently, the combined probability of motion, amplitude and size is derived by PDA, and their weight coefficients are estimated adaptively according to their fluctuations. Finally, the relevant parameters including combination measurement are predicted and updated. Some experiments are included and the results show that the performance of target tracking by the proposed approach is significantly enhanced.

  19. Infrared thermography based defect detection in ferromagnetic specimens using a low frequency alternating magnetic field

    NASA Astrophysics Data System (ADS)

    Lahiri, B. B.; Bagavathiappan, S.; Soumya, C.; Mahendran, V.; Pillai, V. P. M.; Philip, John; Jayakumar, T.

    2014-05-01

    A new active infrared thermography based technique is proposed for defect detection in ferromagnetic specimens using a low frequency alternating magnetic field induced heating. The test specimens (four mild steel specimens with artificial rectangular slots of 8.0, 5.0, 3.3 and 3.0 mm depths) are magnetized using a low frequency alternating magnetic field and by using an infrared camera, the surface temperature is remotely monitored in real time. An alternating magnetic field induces an eddy current in the specimen which increases the specimen temperature due to the Joule's heating. The experimental results show a thermal contrast in the defective region that decays exponentially with the defect depth. The observed thermal contrast is attributed to the reduction in induction heating due to the leakage of magnetic flux caused by magnetic permeability gradient in the defective region. The proposed technique is suitable for rapid non-contact wide area inspection of ferromagnetic materials and offers several advantages over the conventional active thermography techniques like fast direct heating, no frequency optimization, no dependence on the surface absorption coefficient and penetration depth.

  20. Precise autofocusing microscope with rapid response

    NASA Astrophysics Data System (ADS)

    Liu, Chien-Sheng; Jiang, Sheng-Hong

    2015-03-01

    The rapid on-line or off-line automated vision inspection is a critical operation in the manufacturing fields. Accordingly, this present study designs and characterizes a novel precise optics-based autofocusing microscope with a rapid response and no reduction in the focusing accuracy. In contrast to conventional optics-based autofocusing microscopes with centroid method, the proposed microscope comprises a high-speed rotating optical diffuser in which the variation of the image centroid position is reduced and consequently the focusing response is improved. The proposed microscope is characterized and verified experimentally using a laboratory-built prototype. The experimental results show that compared to conventional optics-based autofocusing microscopes, the proposed microscope achieves a more rapid response with no reduction in the focusing accuracy. Consequently, the proposed microscope represents another solution for both existing and emerging industrial applications of automated vision inspection.