A Highly Wavelength-Selective Holographic LIDAR System to Detect Marine Mammals

An advanced LIDAR technology is proposed that can rapidly identify submerged marine mammals. The LIDAR devices will be aircraft or ship based and use laser reflections off submerged targets to determine their size and depth. A chief obstacle to tilizingLIDAR methods has been to eliminate sunlight, moonlight or even starlight which can obscure the relatively weak signals coming from less than cooperative targets. Reflected light from undersea targets can be discriminated from stray light in threeimportant ways: (1) time, (2) wavelength, and (3) direction. Phase I targets the development of novel and proprietary holographic filters that precisely select for the laser wavelength (outperforming interference filters) and thereby increase the signalto noise ratio. The proposed system should be operable with existing LIDAR systems, be applicable to imaging systems, function in a variety of environments, improve depth and/or reduce laser power, and be used to discover other submerged objects ofmilitary significance. Once detected, the mammals will be repelled by acoustic signals.While the proposed technology has many military applications, it can also be used to research undersea fauna, map undersea structures, assist in search and rescue, andprevent at-sea collisions.