双自由曲面光束整形系统的虚拟面迭代设计法  

Design method of beam shaping system for double free-form surfaces based on Virtual Surface Iteration method

作　　者：朱泉锦 马浩统 陈炳旭[1,2,3] 邢英琪 林俊杰 谭毅[1,2,3,4] Zhu Quanjin;Ma Haotong;Chen Bingxu;Xing Yingqi;Lin Junjie;Tan Yi(National Key Laboratory of Optical Field Manipulation Science and Technology,Chinese Academy of Sciences,Chengdu 610209,China;Key Laboratory of Optical Engineering,Chinese Academy of Sciences,Chengdu 610209,China;Institute of Optics and Electronics,Chinese Academy of Sciences,Chengdu 610209,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院光场调控科学技术全国重点实验室,四川成都610209 [2]中国科学院光束控制重点实验室,四川成都610209 [3]中国科学院光电技术研究所,四川成都610209 [4]中国科学院大学,北京100049

出　　处：《红外与激光工程》2024年第2期176-186,共11页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(11804339)。

摘　　要：双自由曲面光束整形系统可在不改变光束相位分布的情况下实现光束空间光强分布的按需调控,然而其需要设置虚拟平面来进行双自由曲面面形的求解。研究发现,传统单一虚拟面法在应用于结构紧凑和扩束倍率较大的系统时,存在设计不精准、整形效果差等缺陷,为此,提出了一种基于虚拟面迭代策略的双自由曲面光束整形系统设计方法。基于不同参数的同轴透射式和离轴反射式光束整形系统的数值仿真研究结果,表明该方法可有效规避传统虚拟面法的局限性。以将束腰半径为5 mm的高斯光束整形为半径30 mm的准直平顶光束的透射式双自由曲面光束整形系统为例,虚拟面迭代法所设计的光束整形系统将光强分布均匀性和能量利用率相对于单一虚拟面法而言分别提升了2.93%和8.93%。Objective The double free-form optical beam shaping system can adjust the spatial intensity distribution of the beam without altering its phase distribution.Still,it requires solving for the shape distribution of the double freeform optical surfaces by setting a virtual plane.This study reveals that applying the traditional single virtual surface method to design beam shaping systems with compact structures(short distance between double free-form optical elements)and large beam amplification(the ratio of the cutoff radius of the outgoing beam to the incident beam)ratios have some drawbacks,such as significant errors in solving for the double free-form optical surfaces and reduced shaping effectiveness,which generally includes the energy efficiency of the whole system for the beam and the irradiance uniformity of the beam after shaping.Methods This paper presents a method for designing a free-form optical beam shaping system based on a virtual surface iteration strategy and the concept of misalignment is proposed to evaluate the difference between the obtained second free-form surface and the virtual surface.The first step involves the creation of a virtual plane at the vertex of the second free-form surface and the virtual surface serves as the target surface of the beam exiting from the first free-form surface.Subsequently,all the discrete points on the first free-form surface can be obtained by using the virtual surface and Snell's law,in this case,all discrete points on the second free-form surface can be obtained by using Snell's law given the outgoing beam of the first free-form surface and the target surface of the whole beam shaping system.Finally,an iterative process updates the virtual surface to approximate the true shape of the second free-form surface.Results and Discussions The quantitative analysis examines the influence of the beam amplification ratioβand the axial distance D between the two optical elements on the misalignment between the virtual surface and the actual surface.A negative correlat

关 键 词：高斯光束整形 虚拟面迭代法 自由曲面 不重合度 辐照度均匀度 能量利用率 

分 类 号：TN249[电子电信—物理电子学]