| 摘要 |
PURPOSE:To form easily a through-hole in short time with good accuracy by providing the through-hole to a material to be worked by laser light having a large output then heating the min. diameter part of the through-hole by the laser light of a small output so that said part emits light spontaneously and measuring the inside diameter. CONSTITUTION:The set value corresponding to the inside diameter of a prescribed hole is inputted to a control device 15. When a laser oscillator 1 is operated by a large-output power source 2, working laser light 4 is reflected downward by a dichroic mirror 6 and is focused and irradiated by a focusing lens 7 on a working position 10. When the oscillator 1 is operated by a small-output power source 3, measuring laser light 5 of a small output is reflected by a mirror 6 and is focused on the position 10. If the hole is not yet penetrated, the light is reflected by the base of the hole and the base is heated to emit light spontaneously to the extent of not being worked. The image thereof is formed through the mirror 6 onto a photoelectric transducer for a test body. The diameter thereof is fed in the form of an electrical signal to the control device 15 by which the signal smaller than the set value is discriminated. The power source 2 is then operated again and the working is continued. |
