High-Pulse-Rate Sources for Active Imaging Systems

75787-In support of systems to detect the proliferation of nuclear weapons, Los Alamos National Laboratory has developed a photon-counting, Remote Ultra-Low Light Imaging sensor that has many advantages over conventional range-imaging devices. However, the photon-counting design requires a laser with unique characteristics: namely, a pulse rate in the 1 kHz-1 MHz range with a pulsewidth less than 1 ns. This project will develop compact seed lasers, to generate the needed pulse format, along with a compact power amplifier capable of power levels of 10 W or higher. The seed lasers will use 1064-nm, short-cavity, diode-pumped solid state lasers with either passive or active Q-switches. The amplifier will be an adaptation of a commercial product, configured for this particular application, or, if appropriate, an Yb-doped fiber laser. Phase I will design a passively-Q-switched seed laser; design, construct, and test a short-cavity, actively-Q-switched laser; test an amplifier stage with the short-cavity laser; and design packaging for the entire laser source. The complete laser source for an active Remote Ultra-Low Light Imaging sensor will be developed in Phase II. Commercial Applications and Other Benefits as described by the awardee: Beyond the application to nuclear nonproliferation sensors, the Remote Ultra-Low Light Imaging sensor should find use in aircraft-based surveying systems that provide imaging data for, say, crop and vegetation analysis. Also, the high-pulse rate laser source could find use in micromachining systems, where the high rate would allow high product throughput.