光子学报, 2009, 38 (3): 713, 网络出版: 2010-07-16
湍流对M×N列阵双曲余弦高斯光束传输和远场光束质量的影响
Influence of Turbulence on Propagation and Far-field Beam Quality of M×N Cosh-Gaussian Beams
M×N列阵双曲余弦高斯光束 湍流 传输 远场光束质量 M×N cosh-Gaussian (ChG)beams Turbulence Propagation Beam quality in the far field
摘要
基于广义惠更斯-菲涅耳原理,并采用光束的非相干合成方法,推导出了M×N双曲余弦高斯列阵光束在湍流中的三维光强传输方程.采用桶中功率、β参量和Strehl比作为光束质量的评价参量,研究了湍流大气对双曲余弦高斯列阵光束远场光束质量的影响.研究表明:在湍流大气中,双曲余弦高斯列阵光束的传输将经历三个阶段的变化,并且湍流使得光束传输经历三阶段的进程加快;湍流导致双曲余弦高斯列阵光束扩展、最大峰值光强下降,但是,β参量随光束数目M(N)、相邻子光束间距xd(yd)和光束参量δ的增加而减少,即光束扩展受湍流的影响减小;并且,存在最佳xd(yd)和δ值使得Strehl比取得极大值.因此,适当选取M(N)、xd(yd)和δ可以降低湍流对双曲余弦高斯列阵光束远场光束质量的影响.
Abstract
Based on the extended Huygens-Fresnel principle,the propagation equation of three-dimensional intensity of M×N cosh-Gaussian (ChG) beams through atmospheric turbulence was derived by using incoherent combination.The power in the bucket (PIB),β-parameter and Strehl ratio (SR) were chosen as the parameters characterizing the beam quality in the far field,and the influence of turbulence on the far-field beam quality was studied.It is shown that the M×N ChG beams in turbulent undergo three stages of evolution with increasing propagation distance,and turbulence accelerates the evolution of three stages.The turbulence results in a spreading and degradation of the maximum intensity in the far field.But β-parameter decreases with increasing beam numbers M (N),separate distances xd (yd) and beam parameter δ.And there exists optimal values of xd (yd) and δ,and SR of the corresponding M×N ChG beams reaches its maximum.So a suitable choice of M (N),xd (yd) and δ may reduce the influence of turbulence on the beam quality in the far field.
汤明玥, 陈晓文, 季小玲. 湍流对M×N列阵双曲余弦高斯光束传输和远场光束质量的影响[J]. 光子学报, 2009, 38(3): 713. TANG Ming-yue, CHEN Xiao-wen, JI Xiao-ling. Influence of Turbulence on Propagation and Far-field Beam Quality of M×N Cosh-Gaussian Beams[J]. ACTA PHOTONICA SINICA, 2009, 38(3): 713.