Variable- and fixed-point blackbody sources developed at VNIIOFI for precision measurements in radiometry and thermometry within 100K-3500K temperature range

Abstract

The demands of modern radiation thermometry and radiometry are being satisfied by a large variety of high-precision unique BB sources (both fixed-point and variable temperature) designed for a wide range of temperature from 100 K to 3500 K The paper contains a detailed review of low-, medium- and high-temperature precision blackbodies developed at VNIIOFI as the basis of the spectral radiance and irradiance calibration devices in the rank of National standards. The blackbodies include: ○ variable-temperature (100 K... 1000K) research-grade extended-area (up to 100 mm) models intended to perform radiometric calibrations by comparison with a primary standard source, as well as can be used as the sources for high-accuracy IR calibration ofspace-borne and other systems not requiring a vacuum environment; ○ low-temperature fixed-point blackbodies on the basis of phase transitions of pure metals such as In and Ga sources operating within the medium-temperature range (300K to 400K); these are used for pyrometric measurements, IR-radiometry, preflight calibration of space borne IR instruments; ○ high-temperate wide aperture variable-temperature blackbodies (1800K to 3500K) such as BB3500MP, BB3500YY designed and fabricated, along with fixed-point cells working above the ITS-90 temperatures on the basis of phase transitions of metal-carbon eutectic alloys (Re-C, TiC-C, ZrC-C, HfC-C), which possess unique reproducibility of 0.1% or less.