Method and device for machining workpieces

A method for processing a workpiece irradiated with laser light of a laser, the method comprising:

• penetrating the laser light into the workpiece, a material of the workpiece (1) being at least partially transparent to the laser light;
• focusing the laser light in a focusing zone within the workpiece via a beam shaping optical unit, the focusing zone, in cross section perpendicular to the beam axis, having a flattened shape with a length in a beam direction and a width and a thickness in each case perpendicular thereto, with a thickness of the focusing zone at least one position along the beam axis being smaller than the width and the length of the focusing zone by at least a factor of 5;
• and
• introducing a modification zone having a flattened shape corresponding to the focusing zone within the focusing zone on account of an intensity of the laser light in the material of the workpiece.

A device for processing a workpiece, the device comprising:

• a laser for emitting laser light, the laser being configured to emit the laser light at a wavelength, the workpiece being at least partially transparent such that the laser light can penetrate into the workpiece;
• and
• a beam shaping optical unit for focusing the laser light in a focusing zone within the workpiece, the beam shaping optical unit being designed such that the focusing zone created therewith has a flattened shape with a length in the beam direction and a width and a thickness, the thickness of the focusing zone being smaller than the width and the length of the focusing zone by at least a factor of 5,
• the laser and the beam shaping optical unit being designed such that there is a sufficient intensity of the laser light within the focusing zone to introduce a modification zone in the material of the workpiece, the modification zone having a flattened shape corresponding to the shape of the focusing zone such that the modification zone has a greater extent in the direction of the beam axis and in one direction perpendicular thereto than in a second direction perpendicular to the beam axis.