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Physical Measurement Laboratory / Sensor Science Division

Remote Sensing Group

Projects/Programs

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      Displaying 1 - 20 of 20

      Absolute cryogenic infrared radiometry at the LBIR facility

      Ongoing
      The Strategic Defense Initiative (SDI), and subsequently the Ballistic Missile Defense Organization (BMDO) and the Missile Defense Agency (MDA) of the U.S. Department of Defense (DoD), have motivated NIST's work developing calibration methods and standards for space-based sensors used in missile
      BIB-trap detector

      BIB-trap detector

      Ongoing
      Limitations of Standard BIB Detectors Currently available BIB detectors exhibit excellent detectivity, but are limited in their use for spectral calibrations by detection inefficiency and spectral response inhomogeneity. The maximum quantum efficiency of these doped silicon devices is near 60%

      Calculation of optical constants and dielectric response

      Ongoing
      By optical properties, we mean those of the following sort: the index of refraction n and the index of absorption k, from which one can calculate the dielectric function, loss function, absorption coefficient, reflectance, and so forth from standard formulas. All of these quantities, it should be
      Figure 1. Class of optical setup considered in this work. The aperture can be limiting (as shown in this case) or nonlimiting.

      Diffraction effects in radiometry

      Ongoing
      Essentially, classical radiometry relies on geometrical optics (to relate source radiance), geometrical aspects of an optical layout, and the irradiance at the detector. One considers the propagation of radiation from points on the surface of the source to points on the surface of the detector. In
      Blue rectangle with green line through it. Electron Solid Interaction Illustration.

      Electron-Solid Interactions

      Ongoing
      A measuring instrument produces a signal that depends upon the value of the measurand. The value and its uncertainty are inferred from the signal by using a model of their relationship. Erroneous models lead to erroneous inference. The accuracy of SEM (scanning electron microscopy) is limited by
      Harnessing EUV capabilities for non-destructive metrology

      EUV Scatterometry

      Ongoing
      To measure and inspect the smallest printed features on an IC chip, researchers and manufacturers use a combination of electron scanning modalities (i.e., transmission electron and scanning electron microscopies) and an optical method, scatterometry. Industrially, the most common modality for
      forest

      FOREST

      Ongoing
      The goals of the research are to: Provide a testbed (Forested Optical Reference for Evaluating Sensor Technology, FOREST) for ecophysiological and optical sensors with well-established reference points Quantify ecosystem phenomenology that will allow for better estimates of productivity Link leaf
      HIP engines

      Hyperspectral Image Projector (HIP)

      Ongoing
      Remote sensing instruments and medical imagers are designed to take images composed of many spectral bands, not just the minimum three components used by common digital cameras (i.e., red, green, and blue). These images are referred to as hyperspectral because each pixel contains information for
      hyperspectral imaging images

      Hyperspectral Imaging Standards

      Ongoing
      There has been a surge in interest in hyperspectral imaging for the use in environmental monitoring, medical imaging, and manufacturing, as several examples. Standards provide common reference points that foster an understanding between different entities. The range of standards encompass all
      hyperspectral imager

      Hyperspectral Microscopy

      Ongoing
      NIST has developed a laboratory dedicated to measuring the optical properties of materials through the use of commercial and custom hyperspectral imagers. The custom built hyperspectral imaging microscope covers the 400 nm to 2500 nm spectral range using narrow contiguous spectral bands. This system

      Infrared cryogenic blackbody broadband calibration

      Ongoing
      The broadband chamber and the spectral calibration chamber at the LBIR facility are used for calibrating the customer cryogenic blackbodies. These chambers are cooled by closed cycle helium gas at 20 K to provide a background equivalent to space. The absolute cryogenic radiometers (ACRs) in these

      Infrared optical properties of materials and components

      Ongoing
      Our overall program can be summarized by the following 6 key elements: Provide a traceability path to national scales for infrared optical properties to the infrared optical properties community through, NIST Calibration Service 38075S, Standard Reference Materials, cooperative research and
      earth and moon

      Lunar Spectral Irradiance (LUSI)

      Ongoing
      Earth observing satellite sensors were once the exclusive domain of large satellite platforms used by government agencies for the purpose of national security, defense, weather prediction and disaster mitigation. These satellites typically carry onboard radiometric calibrators that along with pre

      NIST Stars

      Ongoing
      Several current astrophysical research programs require SI traceable flux measurements (also called spectral irradiance) at accuracies higher than currently available. For example, exoplanet research requires improved host star absolute brightness knowledge to better determine habitability

      Optical medical imaging

      Ongoing
      Optical medical imaging technologies proliferate in academic research and yet very few translate into the clinic. Optical techniques have high spatial and spectral resolution, lends itself to portability, and inexpensive relative to conventional imaging modalities such as MRI (Magnetic Resonance
      ACR receiver

      Pico-Watt ACR

      Ongoing
      Design Parameters for Improved ACR Sensitivity An absolute cryogenic radiometer (ACR) is an electrical substitution instrument for calibrating optical power. A bolometer designed so that virtually all incident optical power is absorbed by the radiometer, an ACR allows for absolute calibration

      Primary optical watt radiometer (POWR)

      Ongoing
      The POWR, including the detector module, was completely designed by NIST to have the versatility to grow with NIST's needs and embrace new technologies. It provides optical power measurements with uncertainties of 0.01 % ( k=1), which have been verified by an intercomparison with two other cryogenic

      Theory of the optical properties of materials

      Ongoing
      Around 1998, first-principles calculation of optical constants and dielectric response began to include excitonic effects. Beginning with simple, wide-gap insulators and semiconductors, the field has progressed to studying more complex materials, clusters, and so forth. In the area of core
      MDXR

      Transfer radiometers and reference detectors

      Ongoing
      Use of these radiometers depends on a primary standard detector and a secondary transfer detector. We generally employ an absolute cryogenic radiometer (ACR) as the primary standard detector to calibrate the transfer detector, a Si:As blocked-impurity-band (BIB) detector. The transfer detector is