在共轴三反系统的几何光学成像理论基础上, 研究了成像光谱仪用远心宽视场、大相对孔径离轴三反消像散系统的设计问题, 推导出了平像场、远心三反消像散系统初始结构参量和三级像差的计算方程.在给定系统像方焦距f ′和F/＃的情况下, 只要给定次镜对主镜的遮拦比α1和次镜口径D2的具体值, 就可以得到一个平像场、远心三反消像散成像系统的初始结构, 通过进一步优化可得到满足设计要求的结果.据此设计出一个光谱范围0.4～2.5 μm、焦距f ′=720 mm、相对孔径F/4、线视场角为10°的平像场、远心离轴望远系统, 其主镜为6次非球面, 次镜和三镜为椭球面, 在空间频率27.8对线/mm处, 调制传递函数值大于0.85.

Based on the theory about geometry optics of common-axis three-mirror systems,studied the design problem of telecentric,widefield of view,large relative aperture,off-axis three-mirror anastigmatic telescope systems of imaging spectrometers are studied.The expressions of initial configuration parameters and third-order aberrations for flat field,telecentric,three-mirror anastigmatic telescopes.On the condition of knowing both effective focal length f ′ in image space and F# ,there would be an initial configuration for flat field,telecentric,three-mirror anastigmatic telescopes as long as the concrete numerical values of obstruct ratio α1 of second mirror relative to primary mirror and aperture D2 of second mirror are given.A satisfied result could be obtained after optimization.A flat field,telecentric,off-axis telescope system with 720 mm focal length,F/4 relative aperture,10°field angle is designed,which covers 0.4~2.5 μm spectral range.The primary mirror is six order asphere,and the secondary mirror and third mirror are both ellipsoid.When space frequency is at 27.8 lp/mm,the module translate function is over 0.85.