The results of a bilateral intercomparison of radiometric temperatures of a high-temperature blackbody from 2100 K to 3100 K measured using filter radiometers are described. The measurements took place over a ten-day period in October 1998 at the PTB-Braunschweig using filter radiometers from the PTB and from the NIST. The intercomparison revealed that the radiometric temperatures determined using the NIST and the PTB filter radiometers differed from each other by 2.4 K at 2100 K to 5.1 K at 3200 K, with the NIST values always lower in temperature than the PTB values. The main cause of the temperature difference was due to the difference the absolute spectral responsivity leading to a difference in the radiometric temperatures.
Issue: No. 5
Pub Type: Journals
absolute radiometry, filter radiometers, intercomparison, radiometric temperature, spectral irradiance responsivity