Compact, Medium Power 4 Micron Laser System

An compact medium power (>IO W), quasi-cw diode pumped solid state laser is proposed capable of emitting radiation at 4 pm and/or other wavelengths in the 3-to-5 gm band with high beam quality. The laser system takes advantage of wavelengths available with cascade processes under resonant pumping conditions from certain rare-earth doped materials. Room temperature operation is achieved by exploiting the unique properties of single crystal fiber lasers, which are ideally suited to operating on relatively low gain transitions in quasi-three-level systems due to the inherent energy confinement afforded by a guided configuration. By exploiting low thresholds, excellent mode quality and compatibility with available diode laser pumping, the proposed approach for the medium power, cw mid Infrared laser system contains several innovative elements for power scaling with minimal risk of damage, all from a very small package. The laser system concept proposed is consistent with many IRCM and other similar program requirements.