Abstract: An electronic still camera is equipped with a white balance sensor and a white balance adjustment circuit so that when photographs are taken underwater (whether only the subject or both the camera and subject are underwater) the white balance in the vicinity of the camera can be measured and then used by the adjustment circuit to provide pictures having properly balanced colors. In one embodiment, a control circuit calculates a gain amount to be applied to the different color signals detected by an image sensor, and then the adjustment circuit uses these gains to adjust the image signals. The camera also may be equipped with an underwater discrimination sensor to determine whether the camera is underwater.

Abstract: The present invention utilizes laser imaging, detection and ranging (LIDAR) as an optical source for an imaging system for helmeted divers who work in highly light backscattering fluid mediums. A laser emitter and detector in waterproof enclosures(s) are mounted on the divers helmet, and send signals to a topside LIDAR processing system, which processes them and sends them back down to the diver in the form of an image of the fluid environment on a viewing screen which is attached to the diver's helmet by a hinged bracket, leaving the diver's hands free for any required tasks. The LIDAR processing equipment is operated by support personnel above the surface of the water, while the imaging equipment on the diver sends and receives signals from the remote processing equipment by wires which run along the diver's hose. The system has the effect of reducing the perceived suspended particles in the fluid medium, thereby increasing identification and detection capabilities for the diver.

Abstract: An imaging lidar system is presented which is adapted to decrease the backscattering at the receiver when a target is viewed in reflection and to increase the backscattered reflection when the target is viewed in obscuration by operating the airborne lidar imaging system bistatically in the former case, and monostatically in the latter case. In accordance with a first embodiment of the present invention, a retractible prism and remote reflecting mirror are used to direct the laser transmitter beam downward. The reflecting mirror is offset so that there is a finite angle between the transmitter optical path and the path of the light reflected back into the CCD framing camera. The angle can be varied by moving the reflecting mirror along a track or rail with the appropriate adjustment to the mirror so that the transmitter beam is completely captured and directed downward to illuminate the area viewed by the camera.