| 摘要 |
PURPOSE:To assure a polarization mode always under optimum conditions so as to stabilize the performance and to improve the quality of a processed product by detecting the polarization rate of laser light just before a condenser lens and offsetting the fluctuation thereof by a reflecting mirror. CONSTITUTION:The laser light emitted from a laser oscillator 1 and propagated via the reflecting mirror 3 is converted to a circularly polarized state. A wire 6c which swivels the laser optical path just before the condenser lens 4 by the rotation a motor 6a periodically shuts off the laser light 2 to sample the laser light 2a. The sampled laser light 2a is made incident on an analyzer 8 via the reflecting mirror 7. The mirror 7 offsets the fluctuation of the polarization rate of the sampling laser light 2a so that the laser light 2b having the same polarization mode as the polarization mode of the laser light 2 is made incident on the analyzer 8. The mode of the laser light 2b is checked by a sensor 10. The good processing quality is obtd. in the above-mentioned manner. |
