Method and device for laser processing a workpiece

A device for laser processing of a workpiece having a transparent material, the device comprising:

• a beam splitter for dividing an input laser beam into a plurality of sub-beams, a focusing optical unit for focusing and directing the plurality of sub-beams coupled out of the beam splitter into the workpiece, wherein the plurality of sub-beams are focused to multiple focus spots inside the workpiece for producing modifications in the material of the workpiece, wherein the workpiece has a thickness along z-axis, and
• a feed apparatus for moving the workpiece and/or the plurality of sub-beams relative to each other in a feed direction that is parallel to y-axis orthogonal to the z-axis, wherein the beam splitter and the focusing optical unit are configured so that the focus spots are formed in the material of the workpiece in such a way that a first plurality of the focus spots is arranged in a first plane, and a second plurality of the focus spots is arranged in a second plane, the first plurality and the second plurality of the focus spots being present simultaneously, the first plane and the second plane being perpendicular to the feed direction and spaced apart from each other in the feed direction, and wherein by moving the workpiece and/or the plurality of sub-beams relative to each other in the feed direction, the modifications are produced in the material along a processing surface.