GENERATION OF HIGH-POWER BLUE-LIGHT IN PERIODICALLY POLED LINBO3

We report the generation of 450-mW average blue (473-nm) power by freq uency doubling of a diode-pumped 946-nm Nd:YAG laser. We achieved puls ed operation at a high repetition rate (similar to 160 kHz) by driving the relaxation oscillations of the laser. A 40% conversion efficiency to the second harmonic was obtained in a single-pass, extracavity, fi rst-order, quasi-phase-matched process in which periodically poled lit hium niobate (period 4.5 mu m, thickness 0.5 mm, and length 15 mm) at 140 degrees C was used. The resulting high-power blue beam was circula r in profile and nearly diffraction limited, indicating that photorefr active effects do not appear to limit device performance. (C) 1998 Opt ical Society of America. OCIS codes: 160.3730, 190.2620, 190.4160, 190 .4360, 190.4400, 220.4000.