| 摘要 |
PURPOSE:To automatically correct a deviation of the optical axis of laser light by measuring the intensity of the laser light with a photodetector after the laser light passes through a slit and discriminating the deviation from the variation of the intensity, and then, rotating an already provided mirror or newly provided transparent glass plate. CONSTITUTION:A photodetector 25 is provided immediately after a mirror 8 which is provided on the laser light axis and can transmit about 10% of the laser light and the intensity of the laser light shaped by a variable slit 5 is measured with the photodetector 25. The signal of the photodetector 25 is compared with a reference value at a control circuit 26 and a motor driver 27 is controlled in accordance with the difference between them. The motor driver 27 is composed of a circuit which drives two sets of motors and can rotate mirrors 28 and 29 independently from each other and a deviation of the laser light axis can be corrected without man's hands. Therefore, even if the laser light axis deviates, the deviation can be discriminated and automatically corrected. |
