棱镜第二光学平行度所致的畸变与像倾斜

为合理地校正反射棱镜制造误差产生的像倾斜，文中讨论了棱镜存在第二光学平行度并处于平行光路中时所产生的畸变像差，以及由此畸变引起的像倾斜。分析了竖直物像的特征并给出了畸变像的方程；导出了像逐点的斜率计算公式；证明了全视场的平均像倾斜近似等于零视场的切线像倾斜，进而指明通过棱镜的转动来校正切线像倾斜是合理的，可以消除大部分畸变。

Distortion and image lean of prism with second parallelism

In order to correct reasonably the image lean, the distortion caused by a reflecting prism with a second parallelism in a collimated beam and the image lean introduced by it were presented. The image character of an erect object was analyzed and the image equation of it was provided. The slope formula of the image was derived. It is proved that the tangent image lean of the tangent line of the curved image line which passes through the central image point is approximately same as the average image lean of the combined line of two margin image points. Then it is reasonable to correct the tangent image lean by rotating the reflecting prism. By this way, the greater part of the distortion can be removed.