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

Using a high-temperature black body (HTBB) and filter radiometers calibrate d for absolute spectral power responsivity, the spectral output of the blac k body, whose radiance temperature was determined using the filter radiomet ers, was used to assign spectral radiance to tungsten strip lamps with a pr ism-grating monochromator. The spectral radiance of the HTBB was also deter mined 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 wer e in agreement to 0.5 K near 2900 K, and from 260 nm to 1050 nm, the spectr al radiance of the HTBB did not differ more than 0.5 % in radiance from a s ingle-temperature Planck's law as determined using the tungsten strip lamp.