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An InSb working standard radiometer, first calibrated at NIST in 1999 against a cryogenic bolometer, was recently calibrated against a newly developed low-NEP pyroelectric transfer standard detector. The pyroelectric transfer standard, which can operate at the output of a monochromator, holds the newly realized NIST spectral power responsivity scale between 1.7 and 14 micrometers with an uncertainty of 1 % (k=2). The InSb working standard was also measured at the National Physical Laboratory of United Kingdom in 1999. The less than 2 % spectral power responsivity disagreements obtained on the InSb working standard validate the three independently realized power responsivity scales and verify the long-term stability of the InSb working standard. The InSb working standard was also used in irradiance measurement mode to validate the previously determined spectral irradiance responsivity of four narrow-band InSb radiometers that were applied to calibrate infrared target simulators. The uncertainty of the present spectral irradiance responsivity scale held by the InSb working standard is 2.5 % (k=2) in the 2 to 5.2 micrometers wavelength range.
Eppeldauer, G.
and Podobedov, V.
(2012),
Infrared detector calibrations, 2012 Measurement Science Conference, Anaheim, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=910831
(Accessed October 12, 2025)