US Patent 7507940 Laser underwater camera image enhancer

An apparatus to obtain images of a target by an underwater video camera in a waterproof container wherein the target is illuminated by a laser beam. The shutter of the video camera is kept closed until a laser pulse has covered the distance to the target and nearly back to reduce the effect of reflection of the laser pulse by particles in the water. A holographic beam shaper in the path of the laser beam before a diverging lens is used to provide a 4 by 3 aspect ratio the same as the camera to illuminate the target.