The marking of aircraft, vehicles, and boats for enhanced recognition during searches is of great interest to both the Government and private sector. We propose an exciting concept using novel low-threshold, mirrorless lasing materials for marking a wide variety of objects. The gain medium, which can be in the form of a sheet or paint, can be lased with a suitable pump laser, but does not require a resonator or other hardware. Compared with simple fluorescence, the output is narrow-band, nonsaturable, and of short pulse duration (<100 ps). This very bright, highly specific output can be used as the basis for generating a signal from marked objects. This innovative technique is both inexpensive and highly crash-resistant. Phase I objectives include acquiring data on the characteristics of these high-gain materials in solid matrices, such as sheets or films, and using the results in the conceptual design of a search and rescue system. The proposed effort includes fabrication of prototype materials, measurements of key laser parameters, and analysis of their impact on laser-based systems. It is anticipated that a feasible system concept will result. This work is relevant to NASA search and rescue missions and ranging activities.Success of the program will result in a state-of-the-art laser technique for marking aircraft, vehicles, and boats to enhance locating them during searches. The technology also has numerous applications in such areas as laser television (by providing high-brightness pixels on a flat-panel display), in certain medical procedures (e.g. treating skin lesions), in machine vision, and in special effects for the entertainment industry.
