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SP250 Spectral Irradiance Calibrations



Howard W. Yoon, Charles E. Gibson


This document describes the process of the realization, the maintenance and the dissemination of the spectral irradiance scale and its accompanying uncertainties at the National Institute of Standards and Technology. It describes the measurement procedures for the realization of the scale and the uncertainties of the detector-based spectral irradiance scale. During the realization process, the spectral irradiances are ultimately made Système International d'Unités (SI) traceable to the unit of electrical power through the electrical-substitution cryogenic radiometer and the unit of length through the aperture area and the distance measurements. This document also contains a representative calibration report and values for the NIST-disseminated spectral irradiance standards along with the irradiance calibration procedures manual.
Special Publication (NIST SP) - 250-89
Report Number


calibration, cryogenic radiometer, filter radiometer, high-temperature blackbody, Planck radiance, spectral irradiance scale, temperature, uncertainties


Yoon, H. and Gibson, C. (2011), SP250 Spectral Irradiance Calibrations, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 20, 2024)


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Created July 25, 2011, Updated November 10, 2018