Chamfered-edge laser cleaving of transparent materials

We report on the separation of glass substrates with customized edge contours including C-shapes. To achieve single-pass laser modifications along the entire contour geometry a processing optics is presented where a multitude of foci are simultaneously distributed inside a specific volume using a large-working-volume focusing unit. Tangential angles of the focus trajectory to the surface can be almost arbitrarily chosen and amount to even less than 45-deg in case of aiming for chamfered edges. After having induced laser modifications along the desired edge geometry, separation is done chemically in the present case. The glass articles, thus fabricated, meet the demands of the display industry in terms of bending strength and surface quality.