Combined laser cutting process for interior holes in thick glasses

A novel combined laser cutting process (CLCP) has been successfully employed for the first time, as far as our knowledge extends, to enable the low-damage, high-speed cutting of interior holes in thick glass materials. To generate a precise weakening zone, a comprehensive technique utilizing the full ablation capability of a picosecond laser has been utilized. The cutting surface is split by CO2 laser-controlled crack propagation, and the final separation of the glass substrate is assisted by the temperature field. In this work, round, square, and irregular rectangular holes were cut in 6 mm soda-lime glass by CLCP. At present, the cutting speed is 150 mm/s, the minimum diameter is 60 mm, the edge chipping of two surfaces is lower than 3.5 µm and the maximum roughness of the side wall is 1.03 µm. This study proposes a new way of ultrafast laser cutting inner holes in thick glasses.