空间光学遥感器宽视场波前误差在轨检测方法

发布时间：2018-03-30 04:37

本文选题：光学遥感　切入点：波前传感　出处：《北京理工大学》2015年硕士论文

【摘要】：近年来，随着高分辨率空间光学遥感器的发展，遥感器口径越来越大。由于长焦距、轻量化、可折叠等特性以及空间在轨环境的特殊性，成像质量受到多种潜在因素的影响，导致图像分辨率降低。对于像质下降的问题，一般有两种解决方法，一是利用比较复杂的自适应光学技术，另一种方法是仅采用自适应光学中的波前传感技术进行出瞳波像差的在轨检测，然后通过离线图像复原技术恢复图像。空间相机的视场较宽，不同视场的像差不同，为准确掌握空间相机的像差特性，需要在全视场内布置多个波前传感器；同时又要考虑到，为降低系统复杂性和成本，不易布置太多的波前传感器。不同形式的光学系统，其像差随视场的变化特性可能不同，需根据其变化特性布置测量点数。对于同轴三反线阵空间相机，可尝试在中心视场和2个边缘视场布置波前传感器，根据3个视场的波前误差检测，通过数据拟合的方法，实现全视场波前误差的估计。对于同轴三反面阵空间相机，可尝试在中心视场和4个边缘视场布置波前传感器，根据5个视场的波前误差检测，通过数据拟合的方法，实现全视场波前误差的估计。本文对两种方案的可行性和精度进行了系统的仿真研究。仿真研究中，利用Zemax软件建立同轴三反系统模型，通过Matlab和Zemax之间的DDE通信,在光学系统模型中引入主镜面形误差、次镜位置误差、次镜面形误差、三镜面形误差等误差源，并通过Matlab和Zemax之间的DDE通信,从Zemax中读出各视场波前误差，在Matlab中进行分析。仿真结果表明，同轴三反线阵空间相机宽视场波前误差的在轨检测，在事先存贮原始设计误差的情况下，仅需3个波前传感器即可实现全视场波前误差估计，仅考虑拟合误差时，，绝对误差在10-5量级，相对误差低于5%；同轴三反面阵空间相机宽视场波前误差的在轨检测，可以通过事先存贮原始设计误差，仅需5个波前传感器即可实现全视场波前误差估计，仅考虑拟合误差时，绝对误差在10-4量级，相对误差低于5%，其中Zernike多项式的某些项的系数较小，其估计值的相对误差会较大，但对总误差的贡献不大。该研究为解决线阵、面阵空间相机全视场波前误差的在轨检测问题，提供了一种可行方法。
[Abstract]:In recent years, with the development of high-resolution space optical remote sensor, the aperture of remote sensor becomes larger and larger. Due to the characteristics of long focal length, lightweight, foldable and the particularity of space orbit environment, the imaging quality is affected by many potential factors. There are generally two solutions to the problem of image quality degradation. One is to use the more complex adaptive optics technology. Another method is to detect pupil aberration in orbit only by using the wavefront sensing technique in adaptive optics, and then restore the image by off-line image restoration. The field of view of space camera is wider and the aberration of different field of view is different. In order to accurately grasp the aberration characteristics of space camera, it is necessary to arrange multiple wavefront sensors in the full field of view, and at the same time, to reduce the complexity and cost of the system, It is not easy to arrange too many wavefront sensors. The aberration characteristics of different optical systems may vary with the field of view, so the measurement points should be arranged according to their variation characteristics. We can try to arrange wavefront sensors in the center field of view and two edge fields of view. According to the wavefront error detection of three fields of view, we can realize the estimation of the wavefront error of the whole field of view by the method of data fitting. We can try to arrange the wavefront sensors in the central field of view and 4 edge fields of view. According to the wavefront error detection of the five fields of view, the method of data fitting can be used. In this paper, the feasibility and accuracy of the two schemes are systematically simulated. In the simulation research, the coaxial three inverse system model is established by using Zemax software. Through the DDE communication between Matlab and Zemax, the main mirror shape error, the secondary mirror position error, the secondary mirror shape error, the three mirror shape error and other error sources are introduced in the optical system model, such as the main mirror shape error, the secondary mirror position error, the third mirror shape error and so on. Through the DDE communication between Matlab and Zemax, the wavefront errors of each field of view are read out from Zemax and analyzed in Matlab. The simulation results show that in orbit detection of wide-field wavefront error of coaxial trisode array space camera, only three wavefront sensors can be used to estimate the wide-field wavefront error when the original design error is stored in advance. When only the fitting error is considered, the absolute error is in the order of 10-5 and the relative error is lower than 5. The in-orbit detection of the wide-field wavefront error of the three-sided array space camera can be detected by storing the original design error in advance. Only five wavefront sensors can be used to estimate the wavefront error of the whole field of view. When only the fitting error is considered, the absolute error is in the order of 10-4 and the relative error is less than 5. The coefficient of some items of the Zernike polynomial is smaller, and the relative error of the estimated value will be larger. This study provides a feasible method to solve the problem of in-orbit detection of the wavefront error in the full field of view of linear array and array space camera.
【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V443.5

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