成像光谱仪的离轴反射式光学系统设计

高分辨率成像光谱仪要求光学系统在宽视场和宽波段范围内具有高的空间分辨率和光谱分辨率。根据同轴三反光学系统初级像差理论计算初始结构，并分别将孔径光阑置于主镜、次镜和三镜焦点，通过光阑和视场离轴，设计了无中心遮拦的离轴反射式光学系统。其光谱范围为1.0~2.5 m，焦距f=1 600 mm，相对孔径为1/ 5，视场角为6.861.48，满足成像光谱仪宽视场、大相对孔径离轴三反消象散光学系统的设计指标。

Optical design of off-axis three-mirror anastigmatic system for imaging spectrometer

Imaging spectrometer requires its optical system have high spatial resolution and spectral resolution over wide field of view and waveband range.A design method for unobstructed,off-axis,reflective optical system was proposed.When pupil and field of view were off-axis properly,obstructing between mirrors was avoided based on the three-mirror anastigmatic.According to the parameters,the unobstructed,off-axis three-mirror anastigmatic systems were designed,when the aperture stop was in front of primary mirror,or on the secondary mirror or focal point of third mirror.The optical system has a spectral region from 1.0 μm to 2.5 μm,focal length of 1 600 mm,relative aperture of f′/5,field of view of angle of 6.86°×1.48°.Their imaging qualities reach the diffraction limit and meet the requirements of the imaging spectrometer′s optical system,which has wide field of view and large relative aperture.