超短型内嵌式遮光罩设计

Design of ultra-short embedded baffle

为了在不影响杂散光抑制效果的同时减少空间遥感器的结构尺寸,方便其姿态控制,提出了一种超短型内嵌式遮光罩。介绍了超短型内嵌式遮光罩的基本结构形式及其优化设计方法。重新设计了遮光罩的形状,采用超短型多层遮光筒结构代替了传统设计中过长的外遮光罩。改变了遮光罩与主体结构的安装方式,将遮光罩嵌入式安装于空间遥感器的主体结构,最大限度地压缩了结构尺寸。以某航空相机光学载荷为例,分析了该种遮光罩的可行性和消杂散光效果。采用Light-tools软件优化设计了双层同心圆柱筒结构的遮光罩,并对该遮光罩的杂散光抑制效果进行了评估。模拟计算结果表明,外遮光罩采用超短型内嵌式结构后,遮光罩总长度和重量均减小为传统设计结果的1/3。系统的点源透过率(PST)曲线显示其整体呈下降趋势,且在离轴角大于25°后,光学系统的PST降低到10^(-7)以下。另外,设计的遮光罩能够有效抑制视场外杂散光,其杂散光抑制能力与其他离轴、同轴系统大体相当,满足使用需求。

An ultra-short embedded baffle was put forward to reduce the size of an aerial satellite and to control its attitude meanwhile maintaining the result of stray light suppressing.The basic structure of the ultra-short embedded baffle was introduce,and its optimized design method was given.The shape of the baffle was redesigned,and an ultra-short multilayer shading tube was designed to replace the quite long baffle designed by existing methods.The installation mode between the baffle and the main structure was changed.The designed baffle was installed into the main structure of an air sensor by an embedding manner,by which the size of the baffle was reduced in the greatest extent.Finally,a concrete aerial camera was taken for an example,and the feasibility of this baffle and its effect on the stray light suppressing were analyzed.A baffle with two-layer concentric cylindrical tube was optimizing by Light-tools software and its stray light suppressing was evaluated.The simulation results show that after the ultra-short embedded structured was used in the baffle,its whole length and weight are just one third of that of the traditional one.The Point Source Transmission（PST）shows a declining curve,and the PST value of the optical system is less than 10^（-7） when the off-axis angle is wider than 25°.Furthermore,the designed baffle suppresses the undesired stray-light flux atthe focal plane,the suppressed effectiveness is the same as that of the off-axis and coaxial systems,and meets the requirements of the applications.