一种远距离水下光电成像的方法

为了增大水下光电成像探测系统的探测距离，降低系统造价成本，对距离选通技术中存在问题进行分析研究，提出降低激光单脉冲能量，提升系统运行频率，增加CCD曝光时间的方法。利用噪声随机特性及目标回波的相关特性进行多脉冲累计提高探测距离。对距离选通系统进行适应性改进，并在室内水池进行实验。实验结果表明:此方法可有效增大系统探测距离，且目标图像质量与激光脉冲数量存在一定最优匹配关系，实验中10次脉冲累计获取到29 m距离处的目标图像质量最佳。

Method for enhancing distance in photoelectronic imaging under water

In order to increase the detection distance of the photoelectronic imaging underwater system and decrease its cost, the existing problem in the range gated technology was analyzed and studied. A novel method for decreasing single pulse energy, enhancing system frequency and lengthening exposure time of charge coupled device (CCD) was proposed. Due to the random feature of the noise and relevance feature of the objective reflencetance, the mutiplue frame accumulation could enhance the maximum distance. The range-gated system was improved by such method, which was checked in the indoor water channel by the experiment. The experimental results show that this method can increase the detection distance effectively, and there is an optimum relation between the image quality and laser pulse numbers which is obtained by 10 pulses at the 29 m distance.