小视场高重频激光雷达光机系统设计、装调及性能测试

为了后期研制星载高重频激光雷达提供数据校正及仿真，设计研制了一套小视场高重频激光雷达验证系统。对该激光雷达进行详细的光机系统结构设计，利用Zemax软件模拟发射、接收与后继单元光路图。精确计算出出射光束发散角为0.106 mrad，设计新型的光束转向结构确保正入射到扩束器中。在0.4 mm小孔光阑下，接收单元视场角0.25 mrad，在系统焦平面上的小孔光阑偏心不得超过29 μm，选择高精度三维调整结构对小孔光阑精确定位。整机结构设计采用模块化设计方法，以方形框架为基准，不同单元模块安装在其不同位置，高度集成在尺寸为390 mm×390 mm×550 mm以内。对发射单元进行装校，并检测出发散角为0.11 mrad，与仿真结果相比，相对误差为4.1%；对接收与后继单元进行装校，采用平行光管出射的平行光正入射到接收望远镜，获得系统焦点精确位置，完成高精度的装校。通过对系统增益比进行标定实验，得到系统增益比为1.15，并对系统进行探测实验，探测结果:系统在夜晚气溶胶探测距离可达22 km，退偏振比可达10 km。在白天探测距离可达10 km，退偏振比可达6 km，并与太阳光度计比较，光学厚度相对误差为7.1%。整机性能满足设计要求，为后期做飞行实验打好基础。

Optical-mechanical system design,installation and performance test of lidar with small-field and high-repetition frequency

In order to provide data correction and simulation for later development of space-borne lidar with high-repetition frequency, the lidar verification system with small-field of view and high-repetition frequency was designed and developed. Its opto-mechanical system was designed in detail, and the light path diagram of the transmitting, receiving and aft optical units was simulated by Zemax. The divergence angle of the outgoing beam was accurately calculated to be 0.106 mrad, and the new beam steering structure was designed to ensure the normal incidence into the beam expander. The field of view of receiving unit was 0.25 mrad with the iris diameter of 0.4 mm, the eccentricity of the diaphragm on the focal plane of the system should not exceed 29 μm, so the high-precision three-dimensional steering structure was selected to accurately position the iris. The design of the whole machine structure adopted the modular design concept, the different unit modules were installed in the different positions of the square frame. The structure was highly integrated, and the overall size was 390 mm×390 mm ×550 mm.The system transmitting unit was installed and calibrated, its divergence angle was detected to be 0.11 mrad. Compared with the simulation calculation, the relative error was 4.1%. The receiving and aft optic units were installed and calibrated, and the parallel light emitted by the collimator tube was used to enter the receiving telescope to obtain the precise position of the focal point of the system to complete the high-precision installation and calibration. Through the calibration experiment of the gain ratio of the system, the gain ration is 1.15. The detection experiments on the system show that the system can achieve aerosol detection distance of up to 22 km, and the depolarization ratio can reach 10 km at night. In the daytime, the detection distance can reach 10 km and the depolarization ratio can reach 6 km. Compared with the solar photometer, the relative error of optical thickness is 7.1%. The performance of the whole machine meets the design requirements, which lays a good foundation for the later experiments on the boat-borne.