研究了水体的前后向散射光和目标反射光的传输特性, 运用脉冲激光器和增益型CCD(ICCD)搭建了距离选通激光水下成像实验系统, 建立了计算距离选通激光水下成像系统光信号的数学模型, 分析了图像对比度传递系数与门控信号的关系。编制计算机程序, 根据所搭建实验系统参数计算并绘制了距离选通激光水下成像系统门控信号与图像对比度传递系数的关系曲线, 提出了距离选通激光水下成像系统最佳门控策略。数值计算和实验结果表明：在ICCD未饱和的情况下, 精确开门得到的图像质量最高, 不论是滞后开门或是提前开门都会使图像分辨率有所下降, 但滞后开门比提前开门较为有利, 并且选通门开启的持续时间则应取激光脉宽的1～3倍。

The transmission character of forward-scattering, backscattering and signal irradiance is studied. An underwater range-gated imaging system is built up with pulse-laser and ICCD. A mathematic method of underwater laser range-gated imaging system is given. The relation between imaging contrast and gate-controlled signal is analyzed. The theoretical calculations are programmed, and figures of image contrast and gate-controlled signal are plotted based on typical system programmed. A best strategy of gate-controlling is raised. Relatively, the experiment has been done. The results show that accurate open-time can acquire the best images, and the image is better when open the gate little-later than ahead with the ICCD not saturated. The duration of gating should one to there times of the pulse width.