[OPTICAL REVIEW Vol. 1, No. 2 (1994) 227-229]

Frequency Doubling of Wavelength Locked Laser Diode with a Transmission-Type Filter in a Confocal Optical Configuration

Yasuo KITAOKA, Kiminori MIZUUCHI, Kazuhisa YAMAMOTO and Makoto KATO

Materials and Devices Laboratory, Matsushita Electric Industrial Co., Ltd., 3-1-1, Yagumo-nakamachi, Moriguchi, Osaka, 570 Japan

(Accepted September 12, 1994)

Direct frequency doubling of a wavelength locked laser diode with an optical bandpass filter in a confocal optical configuration is demonstrated. The wavelength of the laser diode was locked in single longitudinal mode oscillation and tuned to phase-matching wavelength of a quasi-phase-matched second harmonic generation device based on a LiTaO3 waveguide. Stable blue light of 4.2 mW was obtained for incident power of 48 mW.

Key words : LD (laser diode), wavelength locking, bandpass filter, confocal optics, SHG (second harmonic generation), QPM (quasi-phase-matched), LiTaO3 (lithium tantalate)