空间太阳极紫外三波段成像光谱仪系统设计  

System Design of Space Solar Extreme Ultraviolet Three-Waveband Imaging Spectrometer

作　　者：段紫雯 邢阳光 彭吉龙[2] 代树武 王颖[3] 朱成林 闫雷 黄一帆[1] 刘越[1] 李林[1] Duan Ziwen;Xing Yangguang;Peng Jilong;Dai Shuwu;Wang Ying;Zhu Chenglin;Yan Lei;Huang Yifan;Liu Yue;Li Lin(School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China;Beijing Institute of Spacecraft Environment Engineering,Beijing 100094,China;Beijing Institute of Spacecraft System Engineering,Beijing 100094,China;Beijing Institute of Astronautical Systems Engineering,Beijing 100076,China)

机构地区：[1]北京理工大学光电学院,北京100081 [2]北京卫星环境工程研究所,北京100094 [3]北京空间飞行器总体设计部,北京100094 [4]北京宇航系统工程研究所,北京100076

出　　处：《光学学报》2024年第6期295-307,共13页Acta Optica Sinica

基　　金：国家自然科学基金(62205027,42274208);中国科学院战略性先导科技专项(XDA15018300)。

摘　　要：太阳上层大气,即日冕、过渡区和色球,是由炽热的高度动态的磁化等离子体构成,其中高度电离的离子发射出丰富的极紫外谱线。空间太阳极紫外光谱成像观测对于捕获太阳上层大气中爆发活动的动态物理演化过程,以及实现对大气等离子体特征参数的精确测量具有重要的意义。然而现有的极紫外光谱成像仪器只能针对太阳上层大气的一个或两个目标区域进行成像观测,缺乏采用单一仪器对整个太阳上层大气区域在大空间和宽波段尺度范围内的光谱进行诊断的能力,严重制约了人们对太阳爆发活动中的能量及物质输运过程的理解。为了利用单个仪器实现对日冕、过渡区和色球的高分辨率同时诊断观测,本文提出并设计了一款同时工作在17~21 nm、70~80 nm和95~105 nm三个波段的太阳极紫外成像光谱仪,该仪器基于非罗兰圆结构下的椭球面变线距(EVLS)光栅像差校正理论,采用狭缝扫描式成像光谱结构,实现了具有大离轴狭缝视场的高空间、高光谱分辨的消像散光谱成像。基于蒙特卡罗统计模拟方法对太阳极紫外三波段成像光谱仪的最优模型开展光线追迹仿真实验,仿真结果表明,所设计的成像光谱仪取得了良好的光栅像差校正效果,系统空间分辨率优于0.6″,光谱分辨率在17~21 nm波段优于0.006 nm,在70~80 nm和95~105 nm波段优于0.008 nm。本文研究对我国未来的太阳极紫外光谱成像仪器的发展和研制具有重要的理论意义,对我国未来的太阳空间探测任务的型号遴选具有重要的参考价值。Objective The solar upper atmosphere including the corona,transition region,and chromosphere is composed of hot and highly dynamic magnetized plasma,from which highly ionized ions emit abundant extreme ultraviolet(EUV)spectral lines.Existing EUV imaging spectrometers can only conduct imaging on one or two target regions of the solar upper atmosphere but cannot diagnose the whole region in a wide spectral and spatial scale using a single instrument.This severely restricts our understanding of the energy and material transport processes in solar eruptive activities.Therefore,we propose and design a solar EUV three-waveband imaging spectrometer with an elliptical varied line-space(EVLS)grating that operates at non-Rowland circle mounting.This innovative solar EUV imaging spectrometer boasts exceptional spectral imaging performance in an extremely large off-axis slit field of view(FOV)while maintaining a compact instrument package.Furthermore,it provides excellent grating aberration correction even at very high spectrograph magnifications and beam speeds.We hope that our spectral imaging strategy and instrument system design will be instrumental in the simultaneous observation of the solar corona,transition region,and chromosphere in the near future.Methods The instrument utilizes an EVLS grating as the diffraction spectroscopic element.To achieve simultaneous correction of aberrations and free-astigmatism in all three spectral bands,we analyze the grating for aberrations by employing the optical path function and Fermat's principle.The correction condition of off-axis aberrations for the grating is obtained by optimizing the elliptical base shape parameters,line-space parameters,and structure parameters of the EVLS grating,with the grating's spectral focusing formula and spatial focusing curve formula considered.The global optimal solution for the instrument is then obtained via the simulated annealing algorithm and computer-aided design method to build the optimal model of the solar EUV three-waveband imaging spect

关 键 词：太阳空间探测 太阳极紫外 成像光谱仪 光栅像差校正 光线追迹 

分 类 号：O434[机械工程—光学工程]