| 摘要 |
PURPOSE: To improve the efficiency of an SHG laser and to reduce the size and electric power consumption by specifying the converging angle of a semiconductor laser beam for exciting a laser crystal consisting of the Cr-contg. fluoride of a resonator. CONSTITUTION: The exciting beam 31 emitted from the semiconductor laser 11 is condensed by a condenser optical system consisting of a semiconductor laser collimator 12, an anamorphic prism pair 13 and a single lens 14 to excite the laser crystal 21 consisting of the Cr-contg. fluoride, more preferably Cr: LiSrAlF6 crystal. The excited laser crystal 21 oscillates the laser beam 32 with the planoconcave type solid-state laser resonator 20 consisting of an incident side resonance mirror 24 and output mirror 25 formed at the end faces of the laser crystal. The converging angle by the condensing optical systems 12 to 14 of the laser beam 31 emitted from the semiconductor laser 11 is specified to <=0.3rad. As the result, the oscillation threshold value of the SHG(second higher harmonic generating) laser is enhanced and the oscillation efficiency is improved. |
