改进型高分辨率宽波段Schwarzschild成像光谱仪研究

针对Schwarzschild结构在成像光谱仪系统中的应用进行了研究。以Schwarzschild结构的像散分析为基础，获得了该结构的完善消像差条件;之后，对该结构进行了改进，由准直镜和凸面镜，以及凸面镜和聚焦镜分别组成了两个消像散的Schwarzschild结构，从而构成了Schwarzschild成像光谱系统。并给出了这种系统的各个光学参数的计算条件。以一工作波段为340~500 nm的紫外-可见成像光谱系统为例进行了设计，从而对设计理论进行了验证。根据优化理论计算了初始结构最优解并进行光线追迹模拟，成功设计了数值孔径0.125，全视场全波段调制传递函数值在奈奎斯特频率(20 lp·mm-1)下大于0.58的高分辨率成像光谱仪光学系统。这种结构的不同变形分别可以作为Czerny-Turner系统，Ebert-Fastie系统或者Offner系统应用，设计结果也表明这种改进的系统设计理论适用于小型宽波段高分辨率成像光谱仪。

Study on the Advanced Schwarzschild Imaging Spectrometer with High Resolution in Broadband

The Schwarzschild optical structure was studied for the application of imaging spectrometer. The perfect astigmatism-corrected condition was obtained based on the analysis of the astigmatism of the Schwarzschild structure. The structure was advanced in the paper. The Schwarzschild imaging spectrum system is composed of two Schwarzschild structures, which are the collimating mirror-convex mirror and the convex mirror-focusing mirror. The calculation was given to present the parameters of the imaging spectrum system. An example of the imaging spectrum system in the waveband of 340~500 nm was designed and proved our design theory. The solution of the initial optimum structure was designed by our theory and simulated. A system with NA 1.25, of which the modulation transfer functions (MTF) of all fields of view are more than 0.58 in the waveband in the required Nyquist frequency (20 lp·mm-1), is presented in the paper. The form of the design structure can be changed as C-T system, Ebert-Fastie system and Offner system. The result also certificated that the optical system theory can be applied to the small scale imaging spectrometer with high resolution and spectral broadband.