Using airy beams for combined glass cutting and edge shaping

Abstract

When glass sheets are cut to shape, ultra short laser pulses with an elongated, usually straight, focal volume (line focus) can be used to modify the workpiece throughout its entire depth with one single laser shot. At the same time, processed glass is often required to have a seamed or round edge, which usually requires an extra grinding step. Alternatively, curved line foci can be used to combine cutting and edge shaping of glass sheets in one laser process. We reconsider the Airy-Gauss beam for this purpose. Plasma ignition in the side lobes of the Airy beam and surface damage provoke unwanted effects, in particular an asymmetric laser modification of the glass sheet. We provide numerical results on the origins of the asymmetry of the volume modification and show that with rather simple optical adjustments a symmetric convex edge can be created in a 920 μm thick glass sheet.