利用神经网络反演遥感相机扫描镜热变形的方法  

Method for retrieving thermal deformation of scanning mirror of remote sensing camera via the neural network algorithm

作　　者：李正达 孙胜利[1,2] 孙小进 陈异凡[1] 韩逸啸 马孝浩 申笑天 Li Zhengda;Sun Shengli;Sun Xiaojin;Chen Yifan;Han Yixiao;Ma Xiaohao;Shen Xiaotian(Key Laboratory of Intelligent Infrared Perception,Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海技术物理研究所、中国科学院智能红外感知重点实验室,上海200083 [2]中国科学院大学,北京100049

出　　处：《红外与激光工程》2023年第10期314-323,共10页Infrared and Laser Engineering

基　　金：国家重点研发计划项目(2021YFB3701502)。

摘　　要：遥感相机的扫描镜通常位于光学系统的最前端,容易受到在轨外热流的影响产生非规则的面型变化,进而影响相机的成像质量。针对该问题设计了基于扫描镜温度值,以神经网络算法为基本,通过温度场变化反演扫描镜面型变化的扫描镜热变形测试方法。以该方法得出的扫描镜的面型变化可以作为后续成像系统面型修正的依据。该方法能够有效地提升遥感相机在轨的温度适用性,延长遥感相机的可用时间。通过该方法计算出的面型变化与理论面型变化的差值优于RMS 12.6 nm,具有较高的面型还原精度,验证了通过扫描镜温度值变化反演其面型变化的可行性。Objective Wide-range and high-resolution imaging is one of the important development directions of remote sensing cameras.In order to achieve wide-range and high-resolution imaging,the most common method is to scan a large field of view through a scanning mirror.As an important component of remote sensing cameras to achieve large field of view imaging,scanning mirrors are usually located at the forefront of the entire imaging system,and expand the imaging field of view by changing the incident optical angle.It is easily to expose the scanning mirror to the direct influence of external heat flow,such as sunlight and Earth's reflected light,which may lead to change in the temperature of the scanning mirror,and the thermal stress can lead to change in the surface figure of the scanning mirror,thereby affecting the imaging quality of the camera and limiting the available time of the camera in orbit.Therefore,when more resources cannot be provided to ensure the temperature stability of the scanning mirror,the best way to achieve high-quality imaging is to compensate for surface change caused by thermal deformation.How to accurately test the surface change of the scanning mirror in orbit becomes a key step in whether to compensate for thermal deformation surface change.Methods The proposed method is based on an algorithm that combines the interferometer data and the temperature of the mirror to establish a relationship model between the temperature of the mirror and the deformation of the mirror surface.In this paper,a neural network algorithm is adopted,which puts the temperature measurement values of the mirror as the input and the surface figure change of the mirror as the output(Fig.4).The function of inverting the surface mirror change of the mirror through the temperature values of the mirror can be realized.The input temperature values are provided by eight temperature measuring points on the back of the mirror(Fig.7).The surface figure of the mirror is expressed using a Zernike expression,including Power,Astigm

关 键 词：空间光学 热应力分析 图像分析 神经网络算法 

分 类 号：O439[机械工程—光学工程]