In-depth comparison of conventional glass cutting technologies with laser-based methods by volumetric scribing using Bessel beam and rear-side machining

With the development of industrial lasers and novel glass processing techniques, which offer high speed, quality and precision, this becomes an attractive alternative to conventional methods, such as mechanical scribing and cleaving, diamond saw and waterjet cutting, commonly used in the industry. However, the emerging techniques lack thorough validation with respect to well-established methods. To this end, we present a detailed comparison of different glass cutting methods, taking into account surface quality, side-wall roughness, residual stresses and flexural strength. In addition, samples were examined after fracture, and the flexural strength was estimated according to the quarter elliptical corner flaws, which were the main reason of glass failure. Two laser glass processing techniques were investigated - the rear-side glass processing with tightly focused nanosecond laser pulses and sub-nanosecond laser volumetric scribing with asymmetrical Bessel beam. Results were compared to mechanical scribing and breaking, diamond saw and waterjet cutting.