Comparison of the absolute detector-based spectral radiance assignment with the current NIST-assigned spectral radiance of tungsten strip lamps

Abstract

Using a high-temperature black body (HTBB) and filter radiometers calibrated for absolute spectral power responsivity, the spectral output of the black body, whose radiance temperature was determined using the filter radiometers, was used to assign spectral radiance to tungsten strip lamps with a prism-grating monochromator. The spectral radiance of the HTBB was also determined using signal ratios to a tungsten strip lamp calibrated using a scale derived from the radiometric temperature determination of a gold-freezing-point black body. The radiance temperatures found using the two methods were in agreement to 0.5 K near 2900 K, and from 260 nm to 1050 nm, the spectral radiance of the HTBB did not differ more than 0.5 % in radiance from a single-temperature Planck's law as determined using the tungsten strip lamp.