LASER BEAM MACHINING DEVICE

摘要

PURPOSE:To enable sure monitoring of an optical fiber by detecting the light reflected from the inlet side end of an optical fiber which transmits laser light by a photodetector group and monitoring the condition of the optical fiber on the basis of the balance value calculated from the detected value. CONSTITUTION:The laser beam 15 emitted from a CO2 laser oscillating tube 14 is condensed by a condenser lens 16 and the laser beam made incident on the incident end 17a of the optical fiber 17 of a laser knife is emitted from an exit end 17b, then the laser beam condensed by a condenser lens 18 is conducted to a diseased part 19. The reflected light emitted from the incident end 17a is detected by the annular photodetector group 20 and the light energy received by respective photodetecting surfaces 21a, 21b, 21c is converted to electrical outputs. The condition of the fiber 17 is monitored in a central control part 27 from the result of the calculation by an arithmetic circuit 26 for balance. The execution of an abnormal disposition for the deterioration or damage of the optical fiber is thus made possible.