Underwater target detection has been a serious problem of different countries. The discovery is the key to the success of it. Among this, optical detection equipment by carrying on AUV for the detection and identification has a unique advantage. It is an important way of underwater target detection. So the AUV's light vision system is a important part of finish the detection by AUV. .And also to be the basis for the detection and recognition.This paper analyzes the characteristics of underwater images first...