| 摘要 |
PROBLEM TO BE SOLVED: To obtain a laser oscillator with low resonation less in which a solid- state gain medium is used without a high-grade polishing operation. SOLUTION: When a transparent container 3 is irradiated with exciting light 50, a solid-state gain medium 1 which is immersed in a refractive-index matching liquid 2 is laser-oscillated, a laser oscillation is started inside an optical resonator which is constituted of a rear mirror M1 and of an output mirror M2, and laser light S' is outputted from the output mirror M2. A single or a plurality of bulks (Ti:A O3 , Nd:YAG and the like) having an unpolished surface or a surface of the same roughness are used as the solid-state gain medium 1. However, since the medium is immersed in the refractive-index matching liquid 2, an interface scattering operation is suppressed. The refractive-index matching liquid 2 is retreated to the side face of an optical resonator, it is made to flow so as to be passed through a refractive-index-matching-liquid circulating and cooling device 8, a temperature rise at the inside and the outside of the transparent container 3 is prevented, and the degradation of an output characteristic is prevented. The flow of the refractive-index matching liquid 2 can be set to a direction crossed with the optical axis of the optical resonator. |
