Laser light irradiating device

A laser light irradiating device configured to irradiate an object with laser light along a first direction, the laser light irradiating device comprising:

• a laser light source configured to output the laser light;
• a spatial light modulator configured to modulate the laser light output from the laser light source according to a phase pattern and emit the laser light;
• an objective lens configured to converge the laser light emitted from the spatial light modulator onto the object;
• 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 a part of the laser light, wherein
• the phase pattern includes a first pattern in which a part of the laser light entering a pupil plane of the objective lens is modulated and a second pattern in which a remainder of the laser light is modulated,
• the second pattern includes a diffraction lattice pattern for branching the remainder of the laser light into a plurality of diffracted light along a second direction crossing the first direction, and
• the slit member blocks the diffracted light with a slit.