将成像光学系统同时用作激光发射天线的共口径设计可有效减轻卫星载荷质量和应对各种突发状况。首先根据激光通信的能量计算链路, 分析了激光发射天线的设计要求, 明确了激光发射天线与成像光学系统的不同; 然后根据特定的成像光学系统给出了3种具有普适性的共口径设计方法, 并对这3种方法的性能进行了分析和比较, 给出了它们的优缺点和适用范围; 最后对所设计的共口径系统进行了发射光束仿真, 经过对设计系统加工、装调后进行了室内的成像、通信实验, 结果显示发射激光的最小束散角可达182 μrad, 接近系统衍射极限, 出射光斑质量良好, 接收到的图像与成像系统所成图像肉眼观测无失配。初步证实该共口径设计可实现光学系统的成像和通信任务要求。

Research on co-aperture designing methods with which the space imaging optical system can be used as laser transmitting antenna is important to alleviate the load of the satellite and to deal with sudden trouble. First, space laser transmitting design request was analyzed based on the power transferring in laser communication link and the difference between imaging system and laser transmitting system was given. Then three design methods generally used for co-aperture system based on a given imaging optical system were proposed. Their performance were analyzed and compared, and their advantage, disadvantage and fitting areas were given. Finally, the transmitting beam of the designed co-aperture system was simulated, and the imaging and laser communicating experiment were made after system fabricating and aligning. Results show that the least divergence angle of the transmitting beam is about 182 μrad which is close to the system diffraction limitation. Besides the transmitting beam is of great quality and the received image is nearly same as the one obtained by the imaging system when observed with the naked eyes. It is approved that the co-aperture design can satisfy the need of space imaging and laser communicating mission well.