Laser apparatus and laser machining apparatus using same

A laser apparatus comprising:

• a laser oscillator configured to omit laser light;
• an optical path changing component disposed on an optical path of the laser light and configured to change the optical path of the laser light;
• an actuator coupled to the optical path changing component and configured to displace the optical path changing component;
• an optical axis deviation detector surrounding the optical path of the laser light and configured to detect an optical axis deviation of the laser light from an optical axis of the optical path;
• and
• a controller configured to drive the actuator based on a detection result of the optical axis deviation detector to displace the optical path changing component and thereby correct the optical axis deviation of the laser light,
• wherein the optical axis deviation detector includes:
• an annular aperture;
• and
• a plurality of photodetectors on a first surface of the aperture at predetermined intervals, the first surface facing a traveling direction of the laser light,
• wherein an inner diameter of the annular aperture is larger than a diameter of an area through which a mode component of the laser light necessary for machining passes, and each of the plurality of photodetectors is disposed outside the area, and
• wherein the optical axis deviation detector is configured to detect the optical axis deviation of the laser light by detecting magnitudes of output signals transmitted from the plurality of photodetectors, and by determining whether the magnitudes of the output signals indicate that the optical path of the laser light has approached one or more of the plurality of photodetectors of the optical axis deviation detector.