Gentile T R, Houston J M, Hardis J E, Cromer C L, Parr A C
Appl Opt. 1996 Mar 1;35(7):1056-68. doi: 10.1364/AO.35.001056.
A high-accuracy cryogenic radiometer has been developed at the National Institute of Standards and Technology to serve as a primary standard for optical power measurements. This instrument is an electrical-substitution radiometer that can be operated at cryogenic temperatures to achieve a relative standard uncertainty of 0.021% at an optical power level of 0.8 mW. The construction and operation of the high-accuracy cryogenic radiometer and the uncertainties in optical power measurements are detailed.
