大气湍流强度对受限拉盖尔高斯光束轴向光强分布影响的模拟

Simulation of axial beam intensity distribution of limited laguerregaussian beams in different atmospheric turbulences

由Huygens-Fresnel原理,给出了在大气湍流中受到发射圆孔限制的拉盖尔高斯光束轴向光强的表达式.运用MAPLE模拟,得到了不同湍流强度、不同波长、不同发射圆孔孔径下轴上光强的分布图形.结果表明:在不同的拉盖尔高斯光束阶数下,轴上光强在近场发生振荡,幅度随湍流的增强而降低,周期随传输距离的增加而拉大,在远场,随着传输距离的增加,振荡逐渐消失,光强下滑平稳;最后一个平均光强极大值大小与湍流强度关系密切,湍流弱,其大小变化小,孔径大,其位置远;阶数大或波长相对长,轴上光强相对高.

From Huygens--Fresnel principle, the axial light intensity distributions of the Laguerre --Gaussian beams limited by a circular aperture in atmospheric turbulence were exported and the propagation characteristics under different intensity of turbulence and wavelength and aperture transmit were simulated used by MAPLE. The results indicate the oscillation rises in the near--field, its amplitude reduces with the increase of the turbulence intensity and transmitting aperture, the oscillation dies out and the average intensity declines smooth with the increase of propagation distance in far-- field. The position of the last maximum value of average intensity is accordance with the intensity of turbulence and the circular aperture, as the turbulence is smaller, it changes smaller, the circular aperture is larger, the position of it is further, the intensity distributions of axial is also accordance with the rank and wavelength of the beams, it is higher as the wavelength or the rank of the beam is larger.