基于圆锥镜组的空心光束整形器  

Hollow Beam Shaper Based on Axicon Lens Group

作　　者：赵媛媛 叶一东[1] 杨钧兰 王锋[1] Zhao Yuanyuan;Ye Yidong;Yang Junlan;Wang Feng(Institute of Applied Electronics,China Academy of Engineering Physics,Mianyang 621900,Sichuan,China)

机构地区：[1]中国工程物理研究院应用电子学研究所,四川绵阳621900

出　　处：《光学学报》2024年第4期283-292,共10页Acta Optica Sinica

摘　　要：采用一对圆锥镜作为整形器来产生准直平行的空心光束,并根据能量守恒定律得到了整形后空心光束的光强表达式,然后基于菲涅耳衍射积分公式仿真了该空心光束在自由空间不同传播距离处的衍射光斑及截面光强分布图,并计算得到了光束质量因子随截断直径与高斯光束半径的比值和遮拦比变化的关系曲线,为实际获得良好光束质量和整形器的设计提供依据。其次,对该系统进行了锥顶角一致性、偏心及倾斜误差对波面误差的影响分析,结果表明,对于同样大小的误差,设计锥顶角较大时得到的整形光束的波面误差较小,有利于增加加工和装调的容差范围,且装调中的偏心误差和倾斜误差具有一定的等效性,通过调整装调过程中的偏心方向和大小,可以在一定程度上抵消倾斜误差的影响,实现综合误差的互相抵消,为实际应用中的圆锥镜组整形器加工和装调提供有益参考。最后,对整形出的空心光束进行近、远场测量,结果表明实际所得到的光束质量因子符合理论计算结果。Objective Optical tweezer technology makes the mechanical effect of light used in practice,and it can accurately control microscopic particles.Localized hollow beam has important applications in optical captivity and optical tweezers with its physical characteristics such as barrel light intensity distribution and small dark spot size.The method of producing hollow beams by axicon lens is simple and practicable,and it has high conversion efficiency,which is beneficial for the capture of small particles.In the design of optical systems based on an axicon lens,how to balance the energy loss,beam mass,and adjustment error is worth studying,which will make the research more valuable for engineering applications.Methods In this paper,a pair of axicon lenses was used as a shaper to produce collimated parallel hollow beams.First,the mathematical description of the conical mirror type was given,and then the appropriate configuration of the mirror group was selected according to the requirement of practical application.The expression of light intensity of the hollow beam was obtained according to the law of conservation of energy,and then the diffraction spot and cross-section light intensity distribution of the hollow beam at different propagation distances in free space were simulated based on the Fresnel diffraction integral formula.In addition,the relationship curve of beam quality factor with the ratio of truncation diameter to Gaussian beam radius and the blocking ratio was calculated,so as to obtain good beam quality in practice.The influence of cone-top angle consistency,eccentricity,and tilt error on the wavefront error was analyzed.Finally,near-and far-field measurements of the shaped hollow beam was made.Results and Discussions The axicon lens configuration featuring front concave,rear convex,and adjacent planes can either avoid damage caused by backreflected light back to the laser or meet the same design requirements with shorter air spacing(Fig.2).The hollow beam shaped by the axicon lens can maintain good h

关 键 词：光学设计 高斯光束 空心光束 圆锥镜 光束整形 衍射传输 误差分析 

分 类 号：O436[机械工程—光学工程]