Laser processing device and operation checking method

3:

• The laser processing device according to claim 2, further comprising:
• a focusing lens arranged between the spatial light modulator and the objective lens in an optical path of the laser light and configured to focus the laser light;
• and
• a slit member arranged at a focal position on a rear side of the focusing lens in the optical path of the laser light and configured to block diffracted light of the laser light higher than a certain order diffracted according to the diffraction lattice pattern.

6:

• An operation checking method of a spatial light modulator of a laser processing device including a laser light source configured to output laser light, the spatial light modulator configured to modulate the laser light emitted from the laser light source according to a phase pattern and emit the laser light, and a converging lens configured to converge the laser light emitted from the spatial light modulator onto an object, the method comprising:
• a first step in which switching control for switching the phase pattern to be displayed on the spatial light modulator is performed when a second mode different from a first mode in which laser processing is performed by irradiating the object with the laser light is being executed in the laser processing device;
• and
• a second step in which determination on whether operation of the spatial light modulator is normal is made on the basis of a change in intensity of the laser light between before the switching control and after the switching control when the second mode is being executed.