采用激光束主动照明技术,是对远距离暗目标进行成像、定位和跟踪的重要手段, 由于大气湍流等原因, 照明激光束到达靶上会出现光强空间分布不均匀,对成像质Μ和跟踪精度有较大影响。讨论了激光照明效果评价的 主要参数, 提出了采用照明光强起伏功率谱密度作为评价照明光强分布均匀性依据;在建立激光照明大气传输模 型和计算方法基础上,在不同大气参数和光束数情况下对激光照明进行了数值模拟, 得到了目标平面处照明光强 起伏功率谱密度和目标图像, 与实验得到的照明目标图像比较,验证了数值模拟结果的合理性。

Laser illumination is an effective technology for the imaging and tracking to the far dim objects in the air. The laser intensity spatial distribution on the target plane fluctuates usually remarkably, which will decrease image resolution and tracking accuracy in optical system. In this paper the parameters for evaluating illumination effect have been discussed, and power spectral density (PSD) of the illumination laser intensity fluctuation on the target plane is adopted to evaluate the intensity uniformity. A model of illumination laser propagating in atmosphere has been built, numeric simulation for laser illumination to air objects has been carried out and the illumination intensity fluctuant power spectral density and object image have been obtained. Being contrasted with experiment result shows that the simulation is reasonable.