A numerical simulation of machining glass by dual CO2-laser beams

In the flat panel display (FPD) industry, lasers may be used to cut glass plates. In order to reduce the possibility of fracture in the process of cutting glass by lasers, the thermal stress has to be less than the critical rupture strength. In this paper, a dual-laser-beam method is proposed, where an off-focus CO2-laser beam was used to preheat the glass sample to reduce the thermal gradients and a focused CO2-laser beam was used to machine the glass. The distribution of the thermal stress and the temperature was simulated by using finite element analysis software, Ansys. The thermal stress was studied both when the glass sample was machined by a single CO2-laser beam and by dual CO2-laser beams. It was concluded that the thermal stress can be reduced by means of the dual-laser-beam method.