| 摘要 |
PURPOSE:To surely execute the laser beam machining in the constitution where a laser beam oscillator is stopped according to the reflected beam from a work. CONSTITUTION:A circularly polarized mirror 25 converts the linearly polarized laser beam to be outputted from a laser beam oscillator 21 and irradiates it on a work 27. A laser beam splitter and a reflected beam measuring sensor 32 are incorporated in a reflected beam detecting part 28 provided on the rear side of a total reflection mirror 22 of the laser beam oscillator 21. In the laser beam splitter, the laser beam passing through the total reflection mirror 22 passes therethrough, and the laser beam in the polarized direction orthogonal to the polarizing direction of this laser beam is reflected by the reflected beam measuring sensor 32. Thus, the laser beam reflected by a work 4 and returned to the laser beam oscillator 21 is rotated by 90 deg. in the polarizing direction, and the intensity can be detected by the reflected beam measuring sensor 32, and when the intensity of the beam exceeds the set level, the laser beam oscillator 21 is stopped. |
