METHOD AND DEVICE FOR DETECTING INCIDENT CONDITION OF LASER BEAM INTO OPTICAL FIBER AND METHOD AND DEVICE FOR REGULATING INCIDENCE OF OPTICAL FIBER USING THE SAME METHOD AND DEVICE

摘要

PROBLEM TO BE SOLVED: To automatically regulate the incidence of a laser beam into an optical fiber at an appropriate position. SOLUTION: A laser beam LB oscillated from a laser beam oscillator L0 is collected by a collective lens 1, is made incident into an optical fiber 7 from an incident surface 5 of a front fiber connection part 3 a work is irradiated with the laser beam from the tip of the optical fiber 7 and laser beam machining is executed. A temperature sensor 21 to detect the temperature of the optical fiber 7 is provided in the vicinity of the fiber connection part 3. Because an appropriate optical fiber incident condition is obtained when a detected temperature Ts by the temperature sensor 21 is a minimum temperature value Tmin, the optical fiber incident condition can be easily and automatically regulated by moving, e.g. the collective lens 1 in the direction of the optical axis of the laser beam LB and the fiber connection part 3 in two axial directions orthogonally crossing to the optical axis 11 by a moving and positioning device 9 so that the detected temperature Ts by the temperature sensor 21 is the minimum temperature value Tmin.