非制冷红外探测器产生的杂散光会在焦平面形成非均匀的图像,而在探测器窗口附近使用光阑,并对其开孔形状进行优化设计,是抑制杂散光的关键。利用区域法建立了杂散光在焦平面上的照度分布计算模型,并建立了变量模型和目标函数模型,以区间穷举法作为极值搜寻方法,完成了优化光阑开孔的程序编制。针对某款存在杂散光问题的非制冷红外探测器,利用所提数学方法优化设计了光阑的开孔形状,极大地削弱了由杂散光引起的“锅盖效应”,从而验证了光阑开孔形状优化设计方法的正确性与实用性。

The stray radiation generated by an uncooled infrared detector will form a non-uniform image on the focal plane. The key to suppress stray radiation is to use a stop near the detector window and optimize its aperture shape. The model for calculating the illuminance distribution of stray irradiance on the focal plane by Zone method and the models of variables and objective functions are established. The interval exhaustion method is adopted as the extremum seeking method, and the program for optimization is completed. Aiming at an uncooled infrared detector with stray radiation, the proposed mathematical method is applied to optimize its stop aperture shape, which greatly reduces the “pot cover effect” caused by stray radiation, and thus the correctness and practicability of this optimization design method is confirmed.