| 摘要 |
PURPOSE:To protect the human body, etc., from high-output laser beams by a method wherein visible laser beams are superposed on invisible laser beams by an optical parts, which has been provided at an optical path for the invisible laser beams in a condition inclining to the optical path, and detectors are provided on an optical path for the visible laser beams. CONSTITUTION:Large-output invisible laser beams oscillated from a carbonic acid gas laser oscillator 6 are projected to a matter 9 to be irradiated by a condensing system 4. A mirror 8 having an opening in the center thereof is provided at an optical path 15 for the invisible laser beams in a condition inclining to the optical path 15. Visible laser beams generated by a helium neon laser oscillator 7 are made to superpose on the invisible laser beams by the mirror 8 in such a way as to surround around the luminous flux 15. On the other hand, parts of the visible laser beams are contrived in such a way as to be reflected by the mirror 8 and to be detected by detectors 10. In case the laser beams, which are led to the detectors 10, are intercepted on the way to the detectors 10, a shutter 12 is turned into OFF by a logic-driving circuit 1. |
