Method and device for dividing a plane-parallel plate made of a brittle material into a plurality of individual plates by means of a laser

A method of dividing a plane-parallel plate made of a brittle into a plurality of individual plates having a specified edge length comprising:

• introducing thermally induced stresses by means of a laser beam in said plane-parallel plate thereby producing scored lines in a lattice-like pattern in said plane-parallel plate,
• said lattice-like pattern being formed by first producing scored lines along a first working direction starting from an initial defect to be created thereby dividing said plane-parallel plate into a plurality of plate strips (4), and by subsequently producing scored lines along a second working direction which forms a working angle with said first working direction after said plate strips have been moved a certain distance apart from one another, thereby allowing division of said individual plate strips into individual plates,
• wherein said plane-parallel plate or said plate strips and individual plates are held on a clamping table by means of a vacuum, and wherein said plane-parallel plate is bonded to a framed stretch film, said framed stretch film being stretched at least in a direction perpendicular to the first working direction while said vacuum holding said plane-parallel plate is removed in order to create space intervals between said plate strips.