【摘要】 采用相屏近似处理方法对激光通过湍流大气的传输进行了数值模拟。从数值模拟的结果拟合出两个公式:一是通过湍流前后部分相干平顶高斯光束的束宽平方比随阶数、传输距离和湍流强度的变化关系式;一是通过湍流后的相干长度随初始光束相干长度、湍流相干长度的变化关系式。研究发现:部分相干平顶高斯光束分解为相互独立的厄米 高斯光束的叠加;相干性越差的光束受到湍流的影响程度就越小;湍流对光束传输的影响与光束自身相干特性对其传输的影响之间是不相关的。更多还原

【Abstract】 Propagation of laser beam through turbulent atmosphere was numerically studied using phase screen approximation. And partially coherent flat-topped Gaussian beam was expanded as a superposition of independent Hermite-Gaussian modes. In order to fit the results of numerical simulation, two expressions were deduced. One describes the dependence of the rms width of the beam on the order number, the spreading distance and the intensity of turbulence. The other describes the dependence of the coherent length of the beam on that of it’s initial time and that of turbulence. At the same, it is concluded that the coherente of laser beams are worse, the effects of them by turbulence are less; And that on the propagation of laser beams through trubulence, the effects of the initial coherent character of themselves and those of the atmospheric turbulence are independent.更多还原