采用红光激光器、3M微晶棱镜阵列反光膜和长焦高速CCD(电荷耦合器件)构建的折返路径激光成像探测系统, 进行典型天气条件下湍流大气中1 km传输路径上的激光光斑回波成像探测实验, 并配备激光闪烁仪和大气相干长度仪实时监测湍流参数。对激光光斑图像的强度进行了统计分析, 获得了不同位置、不同光斑孔径范围内的闪烁指数和光强起伏的空间相关系数, 并尝试拟合得出了光斑中心点理想的点闪烁指数。将依据该闪烁指数推算出的湍流折射率结构常数与实时监测数据进行对比分析, 结果表明：利用该方法所得的湍流折射率结构常数与激光闪烁仪实测值在变化趋势上具有良好的一致性, 并且折返路径激光成像探测方法容易确保傍轴近似条件, 理论上更符合实际。该系统不仅可用于观测受大气湍流影响的完整的远场激光光斑, 通过定量化理论建模, 还有望发展成为一种单端的大气光学湍流参数成像探测新技术。

Laser spot echo imaging detection experiment is carried out on a 1 km transmission path in turbulent atmosphere under typical weather conditions using a red laser, a 3M microcrystalline prism array reflector, and a telephoto high speed CCD. Scintilloscope and atmospheric coherence meter are used for real-time monitoring of turbulence parameters. Intensity of the laser spot image is statistically analyzed. Spatial correlation coefficients of the scintillation index and the light intensity fluctuation in different positions and different aperture ranges are obtained, and the ideal point scintillation index of the center point of the spot is obtained with the fitting method. The turbulent refractive index struture constant calculated by scintillation index is compared with the real-time monitoring data, and the results show that the turbulent refractive index structure constant obtained by this method is in good agreement with the measured value of the laser scintillator. The laser imaging detection method of the reentry path can easily ensure the paraxial approximation conditions, which is theoretically more realistic. This system can be used not only to observe the complete far-field laser spot affected by atmospheric turbulence, but also to develop a new detection technology of single-ended atmospheric optical turbulence parameter imaging through quantitative modeling.