Infrared thermometry technology with different nonuniformity correction temperatures

In order to keep high accuracy of temperature measurement of the cooled medium-wave infrared thermal imager after nonuniformity correction under different ambient temperatures,the calibration model of the medium-wave infrared thermal imager is analyzed with the consideration of the effect of the nonuniformity correction temperature. The nonuniformity of thermal imager is corrected using surface blackbody under different temperatures. The relationship between the gray and blackbody radiance is obtained by thermometry experiment of blackbody target. The mathematical calculation model of target temperature is established and the error of thermometry result is analyzed. The results show that the drift of gray of thermal image as nonuniformity correction radiance under different correction temperatures can be treated linearly,and is independent on the target temperature. When the nonuniformity is low,the temperature measurement error of the thermal imager is less than 0. 22 ℃,which greatly reduces the temperature measurement error of the cooled medium-wave infrared thermal imager after nonuniformity correction under different correction temperatures.