湍流大气中部分相干双曲余弦高斯光束的M^2因子  

M^2 Factor of Partially Coherent Cosh-Gaussian Beams in Turbulent Atmosphere

作　　者：艾扬利[1] 但有全[1] 明德烈[2] 

机构地区：[1]中国民航飞行学院物理教研室,四川广汉618307 [2]华中科技大学多谱信息处理技术国防科技重点实验室,湖北武汉430074

出　　处：《中国激光》2010年第11期2849-2854,共6页Chinese Journal of Lasers

基　　金：航天支撑基金(20081397);国家自然科学基金委员会与中国民用航空局联合资助项目(61079023)资助课题

摘　　要：基于广义惠更斯菲涅耳原理和维格纳分布函数的二阶矩方法,推导出部分相干双曲余弦高斯(ChG)光束在湍流大气中的束宽、远场发散角和M2因子的解析表达式。研究结果表明,部分相干ChG光束在湍流大气中传输时,均方根角宽度、M2因子和相对M2因子随着传输距离的增大而增大,且与束腰宽度、波长、离心参数、相干参数及湍流强度等有关;均方根角宽度随着光束离心参数的增大存在极小值。当传输距离较远时,随着离心参数的增大,M2因子存在极小值;离心参数较大的光束受湍流的影响较小。Based on the extended Huygens-Fresnel principle and the method of second moments of the Wigner distribution function,the analytical formulas for the root-mean-square（RMS） spatial width,the RMS angular width,and the M^2-factor of the partially coherent cosh-Gaussian（ChG） beam in turbulent atmosphere have been derived,which can be applied to cases of different spatial power spectra of the refractive index fluctuations of the turbulent atmosphere.It can be shown that the RMS angular width,M^2 factor and relative M^2 factor of a partially coherent ChG beam in turbulence increase with the propagation distance and depend on the waist width,wavelength,coherent parameter,decentered parameter,and spatial power spectrum of the refractive index fluctuations.The RMS angular width as a function of the decentered parameter has a minimum at any given propagation distance.For long propagation distance,the M^2-factor as a function of the decentered parameter also has a minimum,and the beams with a larger decentered parameter are less affected by the turbulence.

关 键 词：大气光学 二阶矩 M^2因子 部分相干双曲余弦高斯光束 

分 类 号：O436[机械工程—光学工程]