基于M2因子测量的大气湍流参数的确定方法

基于广义惠更斯-菲涅尔原理以及大气湍流理论,推导出部分相干光束在大气湍流中传输的光束传输M ^{2因子的解析表达式.定量分析了表征大气湍流参数的折射率结构常数 C2_n}和涡旋内尺度 l _{0对 M ^{2因子的影响,并由此提出了一种通过实验测量大气湍流中光束的 M 2因子,进而确定出大气湍流参数的新方法.研究结果表明,由于大气湍流对相干性好的光束影响更为明显,在测量中可采用具有高相干性的基模高斯光束作为测量光源,而测量装 关键词： 2因子')" href="#">光束传输 M 2因子 大气湍流参数 湍流折射率结构常数 湍流涡旋内尺度}}

Method for determining the characteristic parameters of the turbulence based on the measurement of M2-factor

Based on the extended Huygens-Fresnel principle and theory for the turbulence, the analytical expression for the beam propagation factor (M²-factor) of partially coherent beams propagating in a turbulent atmosphere has been derived. The effects of the structure constant of the refractive index fluctuations C²_n and the inner scale of the turbulence l0on the M ^{2 factor have been analyzed quantitatively. Consequently, a new method for determining the characteristic parameters of the turbulence based on the measurement of the M 2 factor by experiments has been proposed. The results show that the laser beams with better spatial coherence property are more sensitive to the effects of turbulence, so the fundamental Gaussian beams with fully coherence can be used as the source in the measurement, and the usual instruments for measuring the M 2-factor can be adopted as the experiment equipments. It is very simple and convenient to determine the characteristic parameters of the turbulence by applying the method proposed in this paper.}