Laser device

A laser device that irradiates an object to be irradiated with laser light, the laser device comprising:

• a laser light source that emits the laser light;
• a reference light source that emits reference light;
• a folding mirror that includes a first reflecting surface that reflects the laser light emitted from the laser light source in a direction different from a traveling direction to guide the laser light to the object to be irradiated and a second reflecting surface that reflects the reference light emitted from the reference light source in a direction different from a traveling direction, and changes an inclination angle of the second reflecting surface with respect to an optical path of the reference light incident on the second reflecting surface when an inclination angle of the first reflecting surface with respect to an optical path of the laser light incident on the first reflecting surface changes;
• a reference light receiver that receives the reference light reflected by the second reflecting surface of the folding mirror;
• a condensing lens that is disposed in an optical path of the laser light from the first reflecting surface of the folding mirror toward the object to be irradiated and condenses the laser light;
• a partial reflection mirror that reflects a part of the laser light from the condensing lens toward the object to be irradiated;
• a partial light receiver that receives a part of the laser light reflected by the partial reflection mirror;
• and
• a controller that detects an abnormality of an inclination angle of the first reflecting surface of the folding mirror with respect to the optical path of the laser light incident on the first reflecting surface of the folding mirror based on an output of the reference light receiver, and detects an abnormality of a spot of the laser light on the irradiated object based on an output of the partial light receiver.