Generation of 20 mW of blue laser radiation from a diode-pumped sum-frequency laser

Resonant intracavity sum-frequency mixing of a diode-pumped Nd:YAG laser and a 100 mW single stripe laser diode, has been used to generate a measured output power of 20 mW of blue laser radiation at 459 nm. This represents a total conversion efficiency of approximately 68% of the single stripe laser diode power incident on the cavity. The laser was also demonstrated to operate over a tuning range of 12 nm via angle tuning of the nonlinear crystal.