Research on the technique of accurately measuring temperature with infrared thermal imagers

In order to measure temperature accurately the authors deduced a general computing formula for the measurement of surface temperature with an infrared thermal imager according to the principles of thermal radiation The authors analyzed the conditions for an accurate measurement of temperature with an infrared thermal imager and emissivitys influence on accurate measurement of temperature The authors also studied the influence of the environment atmosphere and the thermal imager on the accuracy of temperature measurement In addition the authors drew a theoretical curves of various factors influencing the accuracy of temperature measurement The result of the study reveals that when the emissivity is 0.7 the actual temperature is 50degC and the deflection of emissivity is 0.1 then for the 3~5 mum thermal imager the deviation of measurement from the actual temperature is 0.76~0.89degC and for the 8~14 mum thermal imager the deviation is 1.56~1.87degC The result of the study is of practical significance for improving the accuracy of the measurement of temperature and surface emissivity