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Ultraviolet Radiometry With Synchrotron Radiation and Cryogenic Radiometer



Ping-Shine Shaw, Keith R. Lykke, Thomas R. O'Brian, Arp Uwe, H H. White, Thomas B. Lucatorto, J L. Dehmer, Albert C. Parr, R Gupta


The combination of a cryogenic radiometer and synchrotron radiation enablesdetector scale realization in spectral regions that are otherwise difficult to access. Cryogenic radiometry is the most accurate primary detector-based standard available to date, and synchrotron radiation gives a unique broadbandand continuous spectrum that extends from x-ray to far IR. We describe a new cryogenic radiometer-based UV radiometry facility at the Synchrotron Ultraviolet Radiation Facility II at the National Institute of Standards and Technology. The facility is designed to perform a variety of detector and optical materials characterizations. The facility combines a high-throughput, normal incidence monochromator with an absolute cryogenic radiometer optimized for UV measurements to provide absolute radiometric measurements in the spectralrange from 125 nm to approximately 320 nm. We discuss results on photodetector characterizations, including absolute spectroradiometric calibration, spatial responsivity mapping, spectroreflectance, and internal quantum efficiency. In addition, such characterizations are used to study UV radiation damage in photodetectors that can shed light on the mechanism of the damage process. Examples are also given for UV optical materials characterization.
Applied Optics
No. 1


cryogenic, detector standards, electrical substitution, radiometry, SURF, synchrotron radiation


Shaw, P. , Lykke, K. , O'Brian, T. , Uwe, A. , White, H. , Lucatorto, T. , Dehmer, J. , Parr, A. and Gupta, R. (1999), Ultraviolet Radiometry With Synchrotron Radiation and Cryogenic Radiometer, Applied Optics (Accessed May 29, 2024)


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Created January 1, 1999, Updated February 17, 2017