机载轻小型高分辨率成像光谱仪光学系统设计

Optical System Design of Airborne Light and Compact High Resolution Imaging Spectrometer

为了满足轻小型机载遥感平台对成像光谱仪高分辨率和小型化的要求,采用平场Schwarzschild望远系统和基于凸面光栅的Offner光谱成像系统匹配的结构形式,设计了一个工作谱段为0.4~2.5μm、相对孔径D/f=1/3、全视场2ω=7.2°的机载高分辨率成像光谱仪光学系统。分析了Schwarzschild望远系统和Offner光谱成像系统的特点和像差校正方法,利用ZEMAX光学设计软件进行了光线追迹和优化设计,给出了系统的调制传递函数曲线（MTF）和点列图,并进行了分析和评价。设计和分析结果表明,机载高分辨率成像光谱仪可以实现0.6m的空间分辨率和全谱段5nm的光谱分辨率,满足机载宽刈幅遥感成像的应用要求,光学系统结构简单紧凑,具有接近衍射极限的优良像质,易于加工和装调实现,具有较高的实际应用价值。

In order to meet the requirements of smallairborneremote sensing platform for imaging spectrometer with high resolution and miniaturization, an airborne light and compact high resolution imaging spectrometer system is designed using the imaging spectrometer structure form combined fiat-field Schwarzschild telescope system with Offner spectral imaging system. The working wavelength is from 0.4 to 2.5 μm, the relateive aperture is 1/3, and the field of view is 7.2°. The characteristics and aberration correction principles of Schwarzschild telescope system and Offner spectral imaging system are analyzed. Then the ZEMAX software is used for ray tracing and optimization. The modulation transfer function （MTF） curve and spot diagram are given and evaluated. The design and analysis results show that the airborne light and compact high resolution imaging spectrometer optical system can meet spectral resolution of 5 nm and spatial resolution of 0.6 m. Optical system has simple and compact structure and excellent image quality that approaching to the diffraction limit. It can realize the high resolution and miniaturization of system and meet the application requirement of airborne remote sensing.