高精度非致冷长波红外热像仪的辐射标定

为使非致冷长波红外热像仪在不同温度下保持较高的测温精度,建立了考虑探测器工作温度效应的非致冷长波红外热像仪的辐射标定模型。对非致冷长波红外热像仪进行辐射标定实验,在不同黑体温度和不同亮度增益值条件下,获得了16组图像灰度与探测器工作温度之间的函数关系,建立了目标温度的数学计算模型,并对定标结果进行了实验验证。结果表明：在25～40℃,探测器的工作温度效应可做线性化处理,且与目标温度无关。通过设定合适的亮度增益值可使红外热像仪的测温误差〈0.5℃,极大地提高了非致冷长波红外热像仪在不同温度环境下的测温精度。

Radiometric calibration of uncooled long-wave infrared thermal imager with high-precision

In order to achieve the high accuracy temperature measurement for a uncooled long-wave infrared thermal imager under different ambient temperatures,the radiometric calibration model of the infrared thermal imager is established in consideration of the effect of detector operation temperature.The radiometric calibration experiment is then conducted,and sixteen functional relations between image gray levels and detector operation temperatures at different blackbody temperatures and different brightness gain values are obtained.The mathematical calculation model of target temperature is established and the calibration result is verified by experiments.The results show that the detector operation temperature effect can be treated linearly in the range from 25 ℃ to 40 ℃,and it is independent on the target temperature.By setting an appropriate brightness gain,the temperature measurement error of the infrared thermal imager is less than 0.5 ℃,which is a great improvement of the measurement accuracy of the uncooled long-wave infrared thermal imager under different ambient temperatures.