ACOUSTIC DIRECTION AND RANGE TRANSDUCER FOR DIVERS

The contractor has patented technology for a unique process that directly converts a two-dimensional acoustic disturbance, such as a wave front, into an intensity-mapped visible image in real-time without electronic circuitry; i.e., it is a direct pressure gradient imager. This device can allow a small, battery powered acoustic source to be easily located and ranged using a small flashlight sized imager. The imager relies on the piezo-dichroic properties of a continuous layer of a dichroic material thin film that serves as both the sensor and the display. The image can be viewed directly or remotely by using a CCD camera. The source would be placed at a location as a position marker. A diver, using a hand held locator, could identify or signal several other divers with a slight sophistication of the basic device. The phenomenon used allows sensitivity levels of 10^-14 w sec/cm^2. In Phase I the contractor will investigate the engineering specifications applicable to the design of a small, hand-held, real-time, ranging acoustic imager for diver location and signaling in conditions of limited optical visibility. A brassboard model will be produced for the later prototype versions anticipated in Phase II. The extension of this concept to a full acoustic imager for use as a remote mine locator would allow the viewing of mines submerged in low or zero visiblity water.