Generation of blue-green laser radiation using nonlinear frequency upconversion

Nonlinear optical processes permit the design of miniaturized blue-gree laser devices that are pumped by near-infrared sources such as GaAlAs diode lasers. We report on the generation of blue radiation by intracavity frequency doubling and sum-frequency mixing using diode-laser pumped Nd lasers. Using an alternative approach, cw laser emission at 380 and 550 nm was demonstrated at low temperatures by two-photon upconversion pumping of rare-earth laser materials with yellow and near-infrared pump light.