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Developments for a New Spectral Irradiance Scale at the National Institute of Standards and Technology
Published
Author(s)
Benjamin K. Tsai
Abstract
Recent developments for a new spectral irradiance scale realization at the National Institute of Standards and Technology have been targeted to reduce the present relative expanded uncertainties of 0.67 % to 4.34 % (coverage factor of k =2and thus a 2 standard deviation estimate) in the spectral irradiance scale to 0.17 % for the range from 350 nm to 1100 nm. To accomplish this goal, a suite of filter radiometers calibrated using NIST s high accuracy cryogenic radiometerhave been used to measure the temperature of a high-temperature blackbody. A comparison of the filter radiometer calibrations with the spectral irradiance scale along with an evaluation of the blackbody calibration technique have been performed. With the aid of a monochromator, the calibrated filter radiometers will then be utilized to calibrate primary and secondary spectral irradiance standard lamps at NIST.
Tsai, B.
(1997),
Developments for a New Spectral Irradiance Scale at the National Institute of Standards and Technology, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD
(Accessed October 13, 2025)