多角度偏振成像仪杂散光仿真分析

Stray Light Simulation and Analysis of Directional Polarization Camera

杂散光仿真分析是保证多角度偏振成像仪获取高精度偏振辐射数据的关键手段之一。根据仪器光学系统的自身特点,分析了杂散光的主要来源。针对采用点源透过率法难以适用于大视场光学系统杂散光分析的问题,介绍了基于黑斑法原理进行杂散光仿真分析的方法。借助杂散光分析软件LightTools,建立仪器的三维几何模型及光学属性,采用选定视场点反向光线追迹的方法仿真分析得到光机系统的视场外和视场内杂散光系数。分析结果表明,杂散光主要来源于成像视场范围内,且中心视场受到的杂散光影响最大,杂散光系数为3.27%,达到了设计指标要求。此外,采用近轴光线和实际光线正向追迹,模拟得到局部杂光和全局杂光的能量分布,为后期的图像杂散光校正研究提供了理论依据与指导.

Stray light simulation and analysis is one of the key means to ensure high-accuracy polarization radiation data of the directional polarization camera. According to the structural and operating principle of optical system, the dominated resource of the stray light is analyzed. For the difficulty of applying pointsource transmittance method to analyze stray light in large field optical system, method for analysis of straylight based on the principle of black spot is presented. Instrumental three-dimensional geometry model and optical property are established by software of LightTools. The influence of stray light inside and outside the field-of-view of optical-mechanical system is simulated respectively by means of selected field point backward tracing. The result shows that the effect of stray light mainly comes from inside the field-of-view, and on-axis field is influenced mostly. The stray light coefficient is 3.27% which satisfies the requirement of design index.In addition, global stray light and local stray light are simulated by on-axis and real ray forward tracing which provides a theoretical basis and guidance for subsequent image stray light correction.