基于光线追迹非同轴激光雷达重叠因子影响因素的分析研究  

Analysis and Research on Influencing Factors of Non-Coaxial Lidar Overlap Factor Based on Ray Tracing

作　　者：张寅超[1] 王立福 王琛 孙雨婷 陈思颖[1] 郭磐[1] 檀望舒 蒋玉蓉[1] 陈和[1] ZHANG Yinchao;WANG Lifu;WANG Chen;SUN Yuting;CHEN Siying;GUO Pan;TAN Wangshu;JIANG Yurong;CHEN He(Key Laboratory of Photoelectric Imaging Technology and Systems,Ministry of Education,School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China;North Electro-Optic Company Limited,Xi'an,Shaanxi 710043,China)

机构地区：[1]北京理工大学光电学院光电成像技术与系统个教育部重点实验室,北京100081 [2]西安北方光电科技防务有限公司,陕西西安710043

出　　处：《北京理工大学学报》2023年第2期213-220,共8页Transactions of Beijing Institute of Technology

基　　金：国家自然科学基金资助项目(42005137)。

摘　　要：重叠因子是影响激光雷达系统探测近距离大气的一个关键因素,对其进行精确计算有利于获得更准确的探测结果.为此,提出了一种通过光线追迹获得非同轴激光雷达系统重叠因子的仿真方法.该方法利用ZEMAX分别对载入真实机械结构的发射系统和望远镜接收系统进行光线追迹,确定出同一距离处激光强度分布和望远镜的视场函数分布,通过计算重叠区域被望远镜视场函数加权后的激光强度占激光总强度的比例,可得到该距离处的重叠因子,最后通过不同距离处的重叠因子拟合出完整的重叠因子廓线.此外,利用此方法对一套激光雷达系统进行了几何因子廓线仿真,并分析了系统轴间距、光轴失调角度、激光发散角、望远镜视场角以及次镜机械遮挡对系统重叠因子廓线的影响.仿真结果表明当激光光轴偏离望远镜光轴的角度等于望远镜视场角和激光发散角差值的1/2时,远场的重叠因子不能达到1,这对激光雷达系统的设计和安装提出了更高的要求.Overlap factor is a key factor that affects atmosphere detection of lidar system at near range. The accurate calculation of overlap factor is helpful to obtain more accurate detecting results. To this end, a simulation method was proposed based on ray-tracing technique to obtain the overlap factor of non-coaxial lidar system.Firstly, using a ZEMAX optical simulation software, the ray-tracing was carried out on the transmitter and telescope receiver loaded with mechanical structures to calculate the laser intensity distribution and the field of view(FOV) function of the telescope at a given distance. Then the ratio of the FOV-weighted laser intensity to the total intensity was calculated, obtaining the overlap value at the given distance. Finally, the full overlap profile was fitted through the overlap values at different distances. And this method was applied to simulate an overlap profile for a specific lidar system, and analyze the impact of axis displacement, optical-axis misalignment, laser divergence, the FOV of the telescope, and mechanical obstructions on the overlap profile of the system. The results show that when the deviation angle between the optical axes of the laser and the telescope is equal to half of the difference between the FOV of the telescope and the divergence angle of the laser, the overlap factor cannot reach 1 in the far-field, which puts forward higher requirements for the design and installation of the lidar system.

关 键 词：非同轴激光雷达 光线追迹 机械遮挡 重叠因子 失调 

分 类 号：O436[机械工程—光学工程]