“高分四号”卫星相机工作在杂光环境严峻的地球静止轨道，必须进行深入的杂散光分析与抑制设计以减小杂散光的影响。文章分析了相机的杂散光来源，介绍了适合“高分四号”卫星相机的杂散光评价指标，并结合“高分四号”卫星相机太阳规避分析和相机R-C光学系统特点分析，详细设计了主遮光罩及挡光环、蜂窝结构的次镜遮光罩、中心消光筒及挡光环、杜瓦内多级冷屏等杂光抑制结构。在此基础上，建立了相机结构的几何模型和表面属性，利用Tracepro杂光分析软件分别对“高分四号”卫星相机的各个通道进行了杂散光分析，并根据分析结果对相机的杂光指标进行了计算和评价。计算得到了可见光和中波红外两个通道的杂光系数以及不同角度下的点源透射比曲线，其中可见光通道杂光系数1.1%，中波红外通道杂光系数0.63%，两通道的点源透射比均低于1×10–6。最终结果表明，“高分四号”卫星相机杂光抑制措施有效，各通道杂光抑制效果良好。%GF-4 satellite camera works in an environment with severe stray light, so stray light analysis and suppression must be done in-depth. Stray light assessment indexes (inclued veiling index and point source transmittance) are introduced in this paper, which are applicable for GF-4 satellite camera. By analyzing the stray light sources and avoiding of sunlight invasion, together with characteristics of GF-4 optical system, baffles, vans and other stray light restrain structures are designed. Stray light analysis is done in each optical channel of GF-4 satellite camera, and with the result of analysis, stray light index is calculated and assessed. Results show that the veiling index of visible channel and middle infrared channel are 1.1% and 0.63% respectively, the PSTs of both channel are less than 1×10–6. The results indicate that stray light restrain structures get its effectiveness and GF-4 satellite camera has a low stray light level.
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