对红外光学系统自身热辐射进行了评估方式、计算方法和实验测量研究。首先, 介绍并比较了两种自身热辐射的评估方式, 即有效发射率和等效黑体辐射温度; 其次, 详细介绍了基于实验结果的自身热辐射的等效黑体辐射温度的计算方法; 最后, 利用自身热辐射测试平台, 对同轴全反型红外光学系统的自身热辐射进行测量实验, 并进行了误差分析计算。结果表明: 自身热辐射的辐射出射度与光学系统有效F数的平方成正比关系, 与透过率成反比关系, 和自身热辐射的灰度输出与积分时间之间的线性系数成正比关系, 计算出该同轴全反型红外光学系统的自身热辐射的等效黑体辐射温度为217.3 K, 经测量和计算出背景模拟板的辐射亮度误差为8.5%, 自身热辐射的灰度输出与积分时间的线性拟合系数的相对不确定度为0.2%, 并说明探测器在5×10-4 Pa中具有良好的稳定性。

Infrared optical system self-thermal radiation was evaluated, calculated and measured. Firstly, it introduced and compared the two kinds of the thermal radiation way of evaluation, effective emissivity and equivalent blackbody radiation temperature; Secondly, the way based on experiment of calculation for equivalent blackbody radiation temperature of self-thermal radiation was introduced in detail; Finally, the coaxial reflection infrared optical system thermal radiation was measured by using self-thermal radiation test platform and error analysis was carried out. The result show that self-thermal radiant exitance is proportional to the square of effectively F number of optical system and the linear coefficient for the output gray of self-thermal radiation between the integral time, is inversely proportional to transmittance. It shows that the equivalent blackbody radiation temperature for self-thermal radiation of coaxial reflection infrared optical system is 217.3 K. Error for radiation form background simulation board is 8.5%, the relative uncertainty of linear coefficient for the output gray of self-thermal radiation between integral time is 0.2%. It shows that infrared detector has a good stability under 5×10-4 Pa.