针对小F数、短后工作距的Cook型光学结构，设计了一种基于光学自由曲面的通道分光方案以及相应的检测方案。该分光方案利用光学自由曲面的多自由度来修正通道分光元件倾斜引入的像散，使透反两通道光学像质均接近衍射极限。采用计算全息检测技术实现分光元件光学自由曲面的面形检测，检测光路的系统波前峰谷值为0.0096λ，均方根为0.0017λ。分光元件及检测方案均满足设计需求，且对小F数、短后工作距的光学系统的通道分光具有借鉴和实用参考价值。

For a Cook optical structure with small F number and short back working distance, a channel splitter based on the optical free-form surface and the corresponding test solution are proposed. The solution uses multi-degree of freedom of optical free-form surface to correct the astigmatism caused by tilt of the splitter, which makes transflective two-channel optical image quality approach to the diffraction limit. Computer-generated hologram testing technology is proposed to test the free-form surface of the splitter. The peak valley of the wavefront is 0.0096λ，the root mean square of the wavefront is 0.0017λ in the testing system. The splitter and its testing solution meet the design requirements, and provide practical reference for the optical system with small F number and short back working distance.