LASER MACHINING DEVICE AND LASER MACHINING METHOD

摘要

A laser processing device includes: a laser light source; a converging optical system; and a reflective spatial light modulator modulating the laser light such that the laser light is caused to branch into at least first processing light and second processing light, and the first processing light is converged at a first converging point and the second processing light is converged at a second converging point. In a case in which W1 is a radius of the first processing light at a front face of the object, W2 is a radius of the second processing light at the front face, and D is a distance between the first converging point and the second converging point when viewed from a direction orthogonal to the front face, the reflective spatial light modulator modulates the laser light such that D>W1+W2 is satisfied.

主权项

1. A laser processing device for converging laser light at an object to be processed so as to form a modified region within the object along a line to cut, the laser processing device comprising:
a laser light source emitting the laser light; a converging optical system converging the laser light emitted from the laser light source at the object; and a spatial light modulator modulating the laser light emitted from the laser light source such that the laser light is caused to branch into at least first processing light and second processing light, and the first processing light is converged at a first converging point and the second processing light is converged at a second converging point by the converging optical system, wherein the first converging point and the second converging point have a positional relationship in which the first converging point is positioned at a first surface side as an opposite side to the laser light entrance side of the object with respect to the second converging point, and the first converging point is positioned at an anterior side in a relative moving direction of the laser light along the line with respect to the second converging point, in the object, and in a case in which W1 is a radius of the first processing light at the first surface, W2 is a radius of the second processing light at the first surface, and D is a distance between the first converging point and the second converging point when viewed from a direction orthogonal to the first surface, the spatial light modulator modulates the laser light such that
D>W1+W2 is satisfied.