Method to Remove the Effect of Atmosphere and Ambient Radiation on Colorimetric Temperature Measurement

Abstract

Traditional colorimetric temperature measurement methods usually make use of visible light and near-infrared band. They commonly yields high accuracy in measuring close targets at high temperature, however low accuracy in measuring distant targets at medium or low temperature. Given the limitations of traditional methods, an infrared colorimetric temperature measurement method which takes the effect of atmospheric parameters and environment radiation into account is proposed. A colorimetric temperature measurement model which environmental radiation is taken into account is derived. In addition, a MWIR camera and two band-pass filters are used for colorimetric temperature measurement to verify the proposed method. The experiment results shows that, absolute error and relative error of temperature measurement using the method considering atmospheric parameters and environment radiation are less than 4°C and 6.7%, respectively; moreover the radiometry error of the gray body is less than 10%, which demonstrates that the proposed method is valid for measuring distant targets at medium or low temperature.