| 摘要 |
PROBLEM TO BE SOLVED: To make a coat film hardly affected by environmental humidity change and prevent output variation of a so-lid-state laser by forming a coat film formed in a mirror surface of an excitation light source side edge face of a resonator by an ion assist deposition method. SOLUTION: Light of wavelength of 1313 nm is confined between a λ/4 wavelength board edge face 13a and a recessed surface 14a which are high reflection surfaces thereto and causes laser oscillation, and laser beam 21 of wavelength of 1313 nm is generated. The laser beam is changed to red second harmonic 20 whose wavelength is half thereof, that is, 657 nm by MgO:LiNbO3 crystal 17 and the second harmonic 20 is projected mainly from the recessed mirror 14. In a resonator surface 13a of a first λ/4 wavelength board 13 which is a resonator and the recessed surface 14a of the recessed surface mirror 14, each layer of high refractive index HfO2 and low refractive index SiO2 is laminated by an ion assist deposition IAD method and a coat film of dense film quality is formed. Therefore, output variation of a laser can be prevented. |
