| 摘要 |
PURPOSE:To machine covered material without damaging base material by controlling a laser oscillator based on output signal from a vibration wave detecting means and light quantity detecting means to detect change in the material of a work. CONSTITUTION:In laser machining of a work 7 in which a base material is covered with a covering material 9, a laser beam, which is emitted from an excimer laser oscillator 2 and reflected part of beam by a part reflecting mirror 3, is made incident on a light quantity detector 4. The light quantity detector 4 outputs a signal corresponding to a light quantity of incident beam. The laser beam irradiated to the work 7 generates sound at machining which is detected by a volume detector 5. A arithmetic means 6 detects a material of work 7 based on the detected signal from the quantity of light detector 4 and volume detector 5, at the timing machining transfers from the covered material 9 to base material 8, the excimer laser oscillator 2 is stopped. By this method, the covered material 9 only is machined without damaging the base material 8. |
