Liquid Crystal-Based Underwater Imager

The contractor proposes a new approach to underwater imaging that directly converts a two-dimmensional acoustic pressure wave into an electronic requirements fo convential piezo-element arrays. The imager relies on the piezo-birefringent properties of a nematic liquid crystal panel that serves as both sensor and display. The capability of nematic liquid crystals has been established and published by the authors and others. Pressure waves established by acoustic transducers are reflected by the target, focused by an acoustic lens system, and converted into a visible image for target identification. A compact device with a volume of 1-2 ft3 for diver-held applications at ranges of about 5 meters, as well as larger versions for increased distances, are feasible. In Phase I liquid crystal panels will be constructed and tested for maximum resolution using the contractor's diffraction-limited acoustic lens system. The engineering specifications applicable to the design of field prototype, to be built under Phase II, will be determined.