| 摘要 |
PURPOSE:To prevent the lowering of the output of a light beam and the damage of an optical guide system, by detecting the deviation of the light beam from the optical axis under the state, wherein the optical axis of the optical guide system and the central ray of the lihgt beam coincide with each other, by plural photodetectors arranged around the light beam and correcting this deviation. CONSTITUTION:A light beam position detecting means of photodetectors 5-1-5-4 consisting of thermocouples and a light beam position detecting means 2 of photodetectors 6-1-6-4 are provided apart in the direction of an optical axis 4 of an optical guide system 3. Photodetectors 5-1-5-4 and photodetectors 6-1-6-4 are arranged oppositely to each other respectively in positions, which are near the circumferential edge of a light beam 7 with a central ray 8 of the light beam 7 and the optical axis 4 coincident with each other, in directions of x and y axes orthogonal to each other with the optical axis 4 as the origin. The optical axis 4 of the optical guide system 3 and the light beam 7 are displaced relatively on the basis of detection signals of light beam position detecting means 1 and 2 to make the optical axis 4 and the central ray 8 coincident with each other, thereby preventing the lowering of the output of a laser beam and the damage of the optical guide system. |
