为满足空间遥感光学系统结构紧凑、体积小以及高分辨率的需求, 提出了一种长焦距紧凑型光学系统的设计方法。基于高斯光学和初级像差理论, 创建了同轴四反射镜系统的初始结构, 通过视场偏置的方法避免二次遮拦。对设计的大口径超长焦距同轴偏视场四反射光学系统进行优化, 系统口径1 800 mm, 有效焦距25 000 mm, 全视场角1°×0.1°。设计结果表明, 系统设计波像差优于λ/50(λ=632.8 nm), 全视场相对畸变小于0.4%, 光学筒长仅为有效焦距的1/10, 结构简单紧凑, 像质接近衍射极限, 对大口径超长焦距空间遥感光学系统的设计具有一定的借鉴作用。

In order to meet the needs of space remote sensing optical system in compact structure, small size and high resolution, a design idea and method of compact optical system with long focal length was studied. Based on the Gaussian optics and Seidel aberration theory, the initial structure of the coaxial four-mirror system was built, and the secondary obstructions were avoided by means of field-bias. A large aperture and ultra long focal length coaxial four-mirror optical system was optimized. The aperture of the system was 1 800 mm, the effective focal length was 25 000 mm,and the design full field angle was 1°×0.1°.The design results show that the wavefront of the system is better than 1/50λ(λ=632.8 nm) ,the relative distortion in the whole field is less than 0.4%, and the total length of this system is only 1/10 of effective focal length (EFL). The structure is simple and compact, the image quality is close to the diffraction limit, and it has certain guiding significance for the design of large aperture and ultra long focal length space remote sensing optical system.