星载多角度偏振成像仪检测方法

Test Method for Spaceborne Directional Polarization Camera

为实现星载多角度偏振成像仪在环境模拟测试、装星测试等场合的检测要求,设计了一种具有多角度、多光谱和偏振性能的测试光源.依据多角度偏振成像仪的工作原理及测试需求,开展了检校光源的设计,完成的光源方案由29个多波段LED平行光管米字型排布构成.通过光学建模,分析了平行光管口径、发散角及安装视场,并在辐亮度计算基础上,完成了LED选型及驱动设计,以及匀光扩散片、衰减片、偏振片及退偏器等组件设计,实现了满足仪器多波段不同动态范围要求的均匀光斑照明及标准偏振度源输出.最终检测结果表明,光源满足多视场点、多光谱、偏振特性测试要求,稳定性优于99.2%,偏振度优于1%,重复安装精度优于1个像元;满足载荷辐射5%、偏振2%、几何1像元的性能检测需求,以及通道切换功能监视等要求.

In order to realize the performance test of the spaceborne directional polarization camera(PDC)in the installation stage and environment simulation test, a light source with multi-angle, multi-spectral and polarization features is designed. The final design bases on the principle of the PDC instrument and test requirements is composed of 29 multi-band LED parallel light tubes arranged in a chinese character "mi"-shaped pattern. Through optical modeling, parameters of the parallel light tube diameter, divergence angle and installation field are analyzed. On the basis of radiance calculation analysis, the design of LED driver,diffusion plate, attenuator, polarizer, and depolarizer component was finished, uniform spot illumination and standard polarized light output were realized, the multi-spectral and different dynamic range test of the instrument were satified. The test results show that it meets the multi-field multi-spectral and polarized test requirements, and the stability of source is better than 99.2% within 2 hours,polarization accuracy is better than 1%, reset accuracy is better than 1 pixel. It can meet the requirements of 5% of radiation, 2%of polarization, the performance requirement of geometry 1 pixel, and the monitoring of channel switching function.