Design and construction of an InGaAs transfer standard for absolute calibration of radiation thermometers

Abstract

The Centro Español de Metrologia (CEM) in ollaboration with the Instituto de Óptica of the Consejo Superior de Investigaciones Científicas (IO-CSIC) are able to calibrate filter radiometers/radiation thermometers with direct traceability to the radiant watt at 650 nm wavelength. This allows CEM to measure thermodynamic temperature in the range from 900 °C to 2500 °C. Currently, some modifications in the calibration set-up are been done to measure at infrared wavelengths (1.6 ¿m), in order to extend the thermodynamic temperatures measuring range down to 400 °C. In this case, the radiance/irradiance standards are based in InGaAs detectors, instead of the Si ones used in the visible range set-up. The design, construction and characterization of these standards will be described in this work.