大视场宽谱段高分辨率分波段机载紫外-可见光成像光谱仪设计

摘要

紫外-可见光（200～500 nm ）成像光谱仪是空间遥感的重要组成部分，本文基于机载紫外-可见成像光谱仪的特殊性和实际应用要求，提出了一种采用面阵CCD的摆扫式成像光谱仪，这样既克服了传统线阵CCD摆扫式成像光谱仪空间分辨率低的缺点，同时又弥补了推扫式成像光谱仪视场范围有限的缺点，能够满足大视场、宽谱段、高分辨率成像光谱仪的应用要求；此外，考虑400～500 nm波段中200～250 nm波段二级光谱的影响和＜290 nm的短波区和＞310 nm的长波区两个波段相差3个数量级的辐射波动，采用了分波段、分系统的方式独立进行消杂光光谱成像。在系统结构设计方面，本着高性能、低成本的设计理念，选用了两镜同心系统作为望远系统，Czerny-T urner平面光栅结构作为成像光谱仪系统的光学设计方案；设计了一种不使用任何辅助光学元件，全部采用球面镜结构的成像光谱仪。整个系统结构简单、紧凑，性能优良，可行性好。全谱段、全视场调制传递函数值在0.6以上。%The ultraviolet-visible (UV-Vis 200~500 nm) imaging spectrometer is an important part of space remote sensing . Based on special requirements and practical application of the airborne UV-VIS spectrometer ,a kind of scanning imaging spec-trometer using area array CCD is proposed ,which can meet the application requirements of large field of view ,wide spectrum and high resolution .It overcomes low spatial resolution of traditional line array CCD scanning imaging spectrometer ,and limited field of view of the pushbroom imaging spectrometer .In addition ,dual channel was designed to reduce stray light .400~500 nm band includes two order spectrum for 200~250 nm band ,and variation of radiance from earth between the shorter wavelength (<290 nm) and the longer wavelength (>310 nm) is above three orders of magnitude .In the structure design of the system , the imaging spectrometer is composed of a two-mirror concentric telescope and two Czerny-Turner plane grating imaging spec-trometers .The whole system doesn’t use any additional optical elements in addition to spherical mirrors .The whole system has the advantage of simple structure ,excellent performance ,and very good feasibility .The modulation transfer function value of full spectrum and full field of view is above 0.6 .