基于双焦透镜的双踪远场自动准直  

Dual-Trace Far-Field Automatic Alignment Based on Bifocal Lens

作　　者：宗楠 唐顺兴[1,2] 郭亚晶 Zong Nan;Tang Shunxing;Guo Yajing(Joint Laboratory of High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;Collaborative Innovation Center of IFSA,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]中国科学院上海光学精密机械研究所高功率激光物理联合实验室,上海201800 [2]上海交通大学,IFSA协同创新中心,上海200240

出　　处：《中国激光》2024年第6期94-99,共6页Chinese Journal of Lasers

基　　金：中国科学院青年创新促进会资助项目(2019246);中国科学院A类战略性先导科技专项项目(XDA25020104)。

摘　　要：在光束传输控制中,反馈系统需要具有较高的角度分辨率,以达到自动准直的精度要求,此外还需要具备一定的角视场,以降低对初始安装和调试的精度要求。提出了一种基于双焦透镜的双踪远场自动准直方案,在同一光学系统中实现了高精度和大视场两种角度分辨率的远场图像反馈系统。基于矩阵光学理论对远场图像反馈系统进行数值分析,给出了双焦透镜的等效传输矩阵,并分析了双焦透镜的角度分辨率和视场特性。设计并开展实验对基于双焦透镜的双踪远场自动准直方案进行了性能演示,实验结果表明,高精度下的角度分辨率约为大视场下角度分辨率的6.9倍,与设计值(6.6倍)基本相符。Objective High-power laser systems are capable of outputting nanosecond pulses with power exceeding megajoule levels,allowing high-temperature and high-density conditions to be achieved in laboratory settings.As a result,they are widely employed in various fields such as high-energy-density physics experiments,inertial confinement fusion,astrophysics,and materials science.Solid-state laser systems based on neodymium glass with long optical path lengths are typically used in high energy laser system,which warrant precise control of beam quality and placement.Researchers have conducted extensive studies to maintain a large field-of-view while improving collimation accuracy.However,owing to the limited resolution and field-of-view of optical systems,it is generally not feasible to achieve high accuracy and a large field-of-view in the same collimation system.Therefore,a larger field-of-view is often compromised to ensure high automatic collimation accuracy.In such cases,precise mounting and a highly stable mechanical structure are required to ensure that the collimated beam enters the field-of-view.However,given that the limits of mounting accuracy and longterm stability of the mechanism can only reach a few hundred microradians,the outcomes of this approach are limited.In this study,we proposed a dual-trace far-field automatic alignment scheme using a bifocal lens that enables us to achieve microradian collimation accuracy and a field-of-view of several milliradians in the same optical system.This approach significantly reduces the need for precision mounting and long-term stability of the mechanical structure.Methods Based on the ghost imaging theory of bifocal lenses,this study proposed a scheme for acquiring far-field feedback images with two different angular resolutions on a single camera.The core of the scheme is a bifocal-thick lens with different curvature radii on the left and right surfaces,coated with a 0°spectral dielectric film on both sides.For the off-axis incident beam,owing to the spectral effect

关 键 词：光学设计 高功率激光 自动准直 远场成像 矩阵光学 

分 类 号：O439[机械工程—光学工程]