Measurement and calibration of infrared integrating radiometer

A new approach to the calibration and measurement of extended sources was introduced in the infrared integrating radiometer BUR. Major factors influencing the precision of the BUR were analysed. Based on the Planck principle, it is deduced that the BUR output voltage is the result of a constant and a monotonic increasing function of radiation luminance from the extended sources. The increasing function can be calculated, thus one standard measurement can determine the constant and complete the calibration. The result of measurement of the standard extended source showed that the relative error of the instrument was less than 5%.