| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately detect a phase difference, and to adjust a resonance length with high performance.SOLUTION: A rear surface of a curved surface input coupling mirror 6 with respect to the surface of a resonance 1 side is formed to be a curved surface, and a mirror 16 with an opening is provided. Thus, one of orbiting light 4 and reflected light 10 advances straight to pass through the curved surface input coupling mirror 6, then passes through a through hole of the mirror 16 with an opening to enter into an optical phase detector 5. The other is diffused or condensed on the curved surface of the curved surface input coupling mirror 6 to be reflected, and then reflected on a mirror part of the mirror 16 with an opening to enter into the optical phase difference detector 5. Accordingly, the reflected light 10 and the orbiting light 4 separately enter into the optical phase difference detector 5 without being overlapped. Thus, a phase difference is detected by easily making light intensity uniform, and a resonance length is easily adjusted with high performance. |
