投影光学系统中的偏振像差分析

当光束斜入射时，光学薄膜存在一定的偏振效应。在飞利浦棱镜系统中，当一定大小孔径角的照明光束斜入射到分色合色薄膜后，S偏振分量和P偏振分量存在一定的相位差，使得线偏振光变成椭圆偏振光。利用琼斯矩阵偏振光线追迹的方法，分析了投影光学系统中由于两偏振分量相位差引起的偏振像差，以及它与暗态泄漏光强和系统衬比度的关系。得出了系统出瞳面上的光波偏振特性，以及在不同大小孔径角的照明光束入射下偏振像差的变化。分析了膜厚监控误差对光学系统偏振像差的影响，发现膜厚监控误差对偏振像差和系统衬比度有很大的影响。所使用的分析方法可以应用于其他大口径光学系统。

Analysis of Polarization Aberration in Projection System

Optical thin films exhibit inevitable polarization effects at oblique incidence. When illuminating light with a large numerical aperture incident on dichroic thin films at a non-normal angle in Philips prism system, linear polarized light is turned into elliptical polarized light because of the difference of the phase shift between s- and p-polarization component. Polarization aberration in projection display system is analyzed based on the theory of Jones matrix polarization ray tracing. The dark-state output and extinction ratio of system are also calculated. Furthermore, the character of polarized light on the exit pupil is given out, and the variation of polarization aberration at different F-number illumination light is analyzed. At last, the influence of monitoring errors of thin film on the polarization aberration is analyzed. The monitoring errors have great impact on the polarization aberration and contrast of the system. The method can be applied to other large aperture optical systems.