摘要
为了研究空心光束在非Kolmogorov湍流传输路径上的区域范围与各参量之间的关系及不同区域内光束的扩展情况,采用广义惠更斯-菲涅耳原理推导了空心光束传输于非Kolmogorov湍流中的二阶矩宽度、瑞利区间及湍流距离的解析式,并利用湍流距离把传输路径分割为3个区域进行数值分析。结果表明,区域Ⅰ、区域Ⅱ的长度及区域Ⅲ的起始点都随湍流广义指数α的增大而先减小再增大(当α=3.11时出现一个极小值),且随遮拦比η和光束阶数M(及N)的增大而增大;M(及N)取值较小时(M(及N)<3),湍流在瑞利区间内对光束扩展造成的影响不能忽略,M(及N)和η越大,越容易忽略湍流在瑞利区间内对光束扩展所构成的影响;光束在传输路径上依次进入区域Ⅰ、区域Ⅱ及区域Ⅲ,其光束扩展逐渐变得更加剧烈,且随着M(及N)和η的增加,区域Ⅱ长度和区域Ⅲ的起始点相较于区域Ⅰ的长度增加更为显著。该研究结果为空心光束传输于湍流中的相关应用提供了参考。
To study the relationship between the region range and the parameters of hollow beam in the non-Kolmogorov turbulence propagation path and the beam expansion in different regions,the expressions for the mean-squared width,Rayleigh range,and turbulence distance of hollow beams propagating through non-Kolmogorov turbulence were given by using the extended Huygens-Fresnel principle,and the propagation path was divided into three regions by using the turbulence distance for numerical analysis.The results show that the length of regionⅠand regionⅡand the starting point of regionⅢdecrease first and then increase with the increasing of the turbulence generalized exponent parameterα(There is a minimal value,whenα=3.11),and increase with the increasing of obscure ratioηand beam orders M(and N).When the value of M(and N)is small(M(and N)<3),the effect of turbulence on beam spread in Rayleigh range can not be ignored.The larger M(and N)andηis,the easier it is to ignore the effect of turbulence on beam spread in Rayleigh range.In the transmission path,the beam enters areaⅠ,areaⅡand areaⅢin turn,and then expands more and more violently.With the increasing of M(and N)andη,the length of regionⅡand the starting point of regionⅢincrease more significantly than the length of regionⅠ.The results provide a reference for the application of hollow beam propagation in turbulence.
作者
陈晓文
魏小琴
汤明玥
邓涵凌
CHEN Xiaowen;WEI Xiaoqin;TANG Mingyue;DENG Hanling(Imaging Department, North Sichuan Medical College, Nanchong 637000, China;Department of Basic Medicine, North Sichuan Medical College, Nanchong 637000, China)
出处
《激光技术》
CAS
CSCD
北大核心
2021年第3期307-312,共6页
Laser Technology
基金
四川省教育厅资助项目(17ZB0163)
南充市科学技术局市校合作科研专项资金资助项目(19SXHZ0239,18SXHZ0163)。
作者简介
陈晓文(1984-),男,副教授,主要从事激光传输与变换方面的研究,E-mail:2098647523@qq.com。
