Key techniques to obtain a sharp image of the long-range target through an opto-electronic tracking system were summarized. To insure the major design parameters of an optical system, the resolution, detection ability and the image plane illumination for the opto-electronic system were analyzed. Based on the effects of atmospheric transmission, optical system and CCD detector, the object-background contrast and the detection ability of a shipborne optic-electronic system were discussed, and the focal length and relative aperture of optical system were reasonably chosen. At last, the detection ability of shipborne optic-electronic equipment was tested on fields based on the developed lens. The results show that the system can meet the demand of the detection range larger than 18 km for flying targets at sea. It provides important testing data and theoretical reference for the design of shipborne opto-electronic system. Meanwhile, the design theory of shipborne optical system is suitable for the designs of vehicle and airborne equipment.