三折式光学窗口对航空相机成像的影响

基于平行光通过倾斜的平板玻璃会使光线发生平移的现象，从几何光学的角度分析了三折式光学窗口对航空相机成像分辨率的影响，在窗口玻璃厚度为25 mm，窗口玻璃之间的夹角为45，照相距离为5 000m的条件下，对焦距1 000 mm 的相机成像偏移量进行了分析计算，计算结果成像偏移量为3.34 m，大于设计要求的1/3 像元.最后，通过试验检验了成像偏移对相机成像分辨率的影响，分析及试验结果表明，相机焦距、窗口玻璃厚度和窗口玻璃之间的夹角越大，相机照相距离越小，使相机成像分辨率越低，尤其是采用三折式窗口玻璃的长焦距相机，不适宜在较近照相距离下照相。

Influence of three section type optical window on imaging quality of aerial camera

Based on the phenomena that parallel rays will parallel move when parallel rays pass the oblique plate glass, the influence of three section type optical window on imaging resolution of aerial camera was analyzed. The focus of the aerial camera was 1 000 mm, the thickness of window glass was 25 mm, and the included angle between window glasses was 45. When the imaging distance was 5 000 m, the value of image offset was 3.34 m which was greater than the value of one-third pixel. The influence of image offset on imaging resolution was tested by experiment. The results show that the greater the focus, the thickness of window glass and the included angle between window glasses, the lower the imaging resolution. And long focus camera is not suitable for imaging under small imaging distance.