| 摘要 |
PURPOSE:To heighten durability by extending the damage time of the end face of an incident side terminal part and to prevent an optical fiber damaged due to tortion by supporting the laser beam incident side terminal part of the optical fiber rotatably freely centering an axis. CONSTITUTION:A cylindrical lens holding body 9 whose both terminals are opened is fitted in and fixed at one terminal part of a cylindrical device case 5, and a lens 7 is loaded at the incident side terminal part of the device case of the lens holding body 9, and an optical fiber holding body 10 is supported rotatably freely at the terminal part at the outside of the device case via an anti-friction bearing 11. The optical fiber holding body 10 is formed in cylindrical shape in which one terminal part is closed, and the incident side terminal part of the optical fiber 3 is inserted to and fixed at a hole 10a formed on a central axis. Then the lens is set so as to collect the laser beam at a position shifted a little from the center of the end face of the incident side terminal part of the optical fiber. By employing such constitution, it is possible to change the position in a circumferential direction of the incident point 11 of the laser beam at the end face of the incident side terminal part of the optical fiber 3 corresponding to the rotation of the optical fiber 3 according to the movement of a hand piece, and also, no torsion is applied to the optical fiber 3. |
