The low distortion all-around view system using fisheye lens for an underwater vehicle

The visual information is one of very important information to operate underwater vehicles which are operated by human. So most unmanned vehicles and remotely operated vehicles (ROVs) are equipped with TV cameras. However the angle of view of the general TV camera for underwater becomes very narrow because of the optical refraction caused by the view port and sea water. In particular, human feel narrow about the horizontal angle of view. So we propose the charge coupled device (CCD) image sensor with a fisheye lens, which provides about 180 degrees horizontal angle of view, as the TV camera for underwater vehicles. And a prototype of the low distortion all-around view system using that for the underwater vehicle was made. As the result of experiment in the water tank, good images were appeared by the system.