分析了不同结构形式的地基折反式光电探测系统的杂散光特性，讨论了相应的杂散光抑制方法。针对有无中间像面的光学系统，分别给出了两种不同的杂散光抑制方案，并对其中的长波红外系统进行了自身辐射分析。结果表明：对于无中间像面的折反系统，外遮光罩可以更好地抑制大离轴角度的杂散光；对于有中间像面的折反系统，采取光阑组合和设置主镜内遮光罩的方式就可以很好地抑制外部杂散光，在满足自身辐射要求的前提下，有效减少因设置外遮光罩而增加的长度和质量，有利于小型化和轻量化。

The stray light characteristics of different catadioptric ground-based photoelectric detection system were analyzed. The relevant stray light suppression ways were discussed. Based on structure with middle image surface and the other one without middle image surface, two different suppression schemes for the stray light were provided respectively. Besides, the thermal radiation for the long wave infrared system was analyzed. The results show that adding out baffle to the catadioptric system without middle image surface can do well obviously in reducing stray light with large off-axis angles. However, adding stops and the inner baffle of primary mirror to the catadioptric system with middle image surface can reduce the outer stray light obviously. This can reduce the length and weight greatly. If the thermal radiation demand can be satisfied, the miniaturization and lightweight design had been realized.