根据激光通信及共口径技术基本原理,对共口径自由空间激光通信光学系统的参数进行了分析,并设计得到了一套离轴式共口径激光通信光学系统。系统光学天线采用离轴两反结构,有效通光口径为160 mm,光束压缩比为10∶1,跟瞄系统采用无焦望远结构,最大跟踪视场为±1 mrad,最佳跟踪精度为2 μrad。利用Zemax软件对系统进行了光线追迹和性能分析,结果表明系统性能优良,波像差优于0.1λ(λ=632.8 nm),并且结构紧凑,公差合理,装配简单,能满足实际应用的需求,对实现中地球轨道(MEO)自由空间激光通信具有一定的工程意义。

According to the basic principle of laser communication and common aperture technology, the parameters of the optical system of common aperture free space laser communication are analyzed, and an off-axis common aperture laser communication optical system is designed. With an off-axis two-mirror structure, the optical antenna of the system has an effective aperture of 160 mm and the beam compression ratio is 10∶1. Tracking and pointing system adopts non-focus telescope structure. The maximum tracking field of view is ±1 mrad, and the best tracking accuracy is 2 μrad. Based on Zemax software, the ray tracing and performance analysis are given. The results show that the wavefront error of the system is better than 0.1λ (λ=632.8 nm), so the performance of the system is excellent. The system is of the compact structure, the reasonable tolerance and the simple assembly. The system can meet the needs of practical application and has certain engineering significance for the realization of medium earth orbit (MEO) free space laser communication.