制冷型红外探测器的冷屏优化设计方法

Optimized Design Method of Cold Shield in Cooled Infrared Detector

制冷型红外探测器的冷屏通常采用直角结构挡光环。经过挡光环侧壁反射的杂散光可以直接到达焦平面,导致探测器的成像质量大幅下降。通过对冷屏挡光环结构进行理论分析,提出了一种可抑制杂散光的挡光环侧壁优化结构。利用LightTools软件对优化前后的冷屏进行了模拟分析。结果显示,杂散光的总功率减少了71.6%。通过实验验证发现,探测器的平均响应非均匀性减少了27.1%,成像效果明显改善。结果表明,这种挡光环侧壁优化结构对于抑制杂散光非常有效。

The cold shield in the cooled infrared detector usually adopts vanes of right angle structure.The stray light reflected by the sidewall of the vanes can reach the focal plane directly,resulting in a significant decrease in the imaging quality of the detector.Based on the theoretical analysis of the vane structure,an optimized structure of the vane sidewall which suppresses stray light is proposed.The LightTools software is used to simulate and analyze the cold shield before and after optimization.The analysis results show that the total power of stray light decreases by 71.6%.Through experimental verification,it is found that the average response non-uniformity of the detectors decreases by 27.1%,and the imaging effect is significantly improved.The results show that this optimized structure is very effective in suppressing stray light.