LASER BEAM OSCILLATION MODE DETECTOR AND LASER DEVICE UTILIZING THE SAME

PROBLEM TO BE SOLVED: To provide a laser beam oscillation mode detector, and also to provide a laser device utilizing the same detector. SOLUTION: Interference fringes are generated at a light-receiving surface of a photodetector 17, utilizing the difference in the optical paths of the optical beams reflected at the front surface and the rear surface of an optical wedge 16, by guiding the laser beam to the optical wedge 16. This interference fringe changes pattern, according to the oscillation mode of the laser beam. The photodetector 17 is constituted of a plurality of photodetectors for detecting, with an arithmetic controller 30, a comparison signal, indicating the ratio of the minimum value and the maximum value of the output signals detected from each photodetector. Here, each photodetector is arranged previously to provide changes in the comparison signal value, according to the oscillation mode of the laser beam. COPYRIGHT: (C)2007,JPO&INPIT