| 摘要 |
PURPOSE:To prevent distortion of a video and to detect positions with high accuracy by using a parabolic mirror for an optical element of a laser beam machine which corrects the deviation between the focal position and processing position of laser light in accordance with the video of a television camera. CONSTITUTION:The laser light 1 transmitted through a mirror 2 is reflected by a bent mirror 15 and enters the parabolic mirror 16. This light is condensed and projected to the butt part 5b of works 5, 5a. The video of the butt part 5b reflected by the parabolic mirror 16, the bent mirror 15 and the mirror 2 is then picked up by the television camera. Since the parabolic mirror 16 formed with a reflecting mirror on the metal surface is used as the means of condensing the laser light 1 at this time, the change in the focal length by the wavelength of the light is obviated and since the parabolic mirror 16 has no spherical aberrations, the distortion of the video is obviated. |
