An absolute radiation standard is constructed for use between 200 and 2000 µ. It is demonstrated that the output is that of a blackbody over this wavelength range. The absolute standard is used to calibrate a secondary standard mercury-arc lamp which is found to have an equivalent temperature in the neighborhood of 3000°K. It is shown that absolute standards can be used either to determine the strength of an unknown signal directly or to calibrate the sensitivity of a monochromator-detector system.
A. J. LICHTENBERG and S. SESNIC, "Absolute Radiation Standard in the Far Infrared," J. Opt. Soc. Am. 56, 75-79 (1966)