【摘要】 根据大视场和快焦比空间遥感高光谱成像仪的研究目标,采用折叠三反施密特望远镜和自由曲面Offner凸面光栅光谱仪结构,设计了一个视场为5°,焦比为2,工作谱段在400～1 000nm,光谱分辨率为5nm的星载高光谱成像仪光学系统。推导了非对称非球面施密特主镜的理论计算方法,介绍了镜面的制造方法。利用Zemax光学设计软件进行了光线追迹和优化设计,结果显示光谱畸变<0.88%,光谱弯曲<1/3探测器像元,所有谱段的光学传递函数均大于0.8,满足星载高光谱成像仪的技术要求。施密特系统结构简单,仅含有一个非球面,在大视场工作时具有像质优良和畸变小的特点,且中心遮拦比小、体积紧凑,适合未来大视场快焦比的大口径星载遥感应用。更多还原

【Abstract】 To meet the application demands of a wide field of view and fast focal ratio for an aerospace imaging spectrometer,a three-mirror folded Schmidt telescope using a freeform Offner convex grating spectrometer was designed to obtain a field of view 5°,focal ratio of 2,spectral range of 400-1 000 nm,and spectral resolution of 5 nm for a space hyperspectral imager.The expression of an axisymmetric anamorphic asphere Schmidt surface was given and calculated,and a manufacturing method was introduced.The optical system for a Schmidt spectrometer was designed and optimized using software Zemax.Results show that spectral distortion is less than 0.88%,the spectral smile is smaller than 1/3 pixel size,and the optical module transfer function is greater than 0.8.These imaging characteristics can meet the requirements of a space imager.The Schmidt system shows a simple configuration and uses only a single aspherical mirror.Because it possesses excellent imaging specifications,small distortion,small central obscuration,and a compact size,Schmidt is the best candidate for a space instrument with a large aperture,large field of view,and fast focal ratio.更多还原