Narrow-Linewidth Tunable Visible InGaAlP Laser, Application to Spectral Measurements of Lithium, and Power Amplification

Coarse and fine tuning of a 3.3 THz sweep range for an optically stabilized InGaAlP laser were realized for the first time by varying the angle of an external grating surface and the length of an external confocal Fabry-Perot cavity while maintaining the narrow linewidth of less than 50 kHz. Optogalvanic spectral shapes of D1 and D2 lines in Li vapor were measured by this laser, and the spectral splitting due to D.C. Stark effect was clearly observed. The laser power was amplified 25 dB by a dye solution which was optically pumped by the second harmonics of a pulsed YAG laser.