A new laser glass cutting technology using femtosecond and CO 2 lasers is presented. Mechanical breaking after scribing using a femtosecond laser was evaluated and compared with the hybrid method for the cutting of flat panel display (FPD) glass. Various laser fluences were tested to determine the threshold energy and optimum grooving conditions without microcracks. The hybrid method was very effective for the FPD glass microfabrication and for performing full cutting without the mechanical breaking process. Consequently, it was found that the FPD panel was clearly cut using the method and the methodologies were very effective even for a mass-production cutting system.

A mathematical model of the dynamics of laser-produced heating, evaporation and plume formation is presented. The condensed material model includes conduction heat transfer as well as melting and evaporation phase changes. The localized heating and evaporation caused by focused laser radiation forms a plume of mixed vapor above the material surface. The beam is absorbed and refracted as it traverses the plume, thus modifying its power density on the surface. In this work, variations of heat transfer rate during laser heating and effects of a plume formed by vapor from an iron surface are studied using an axisymmetric mass, momentum and energy transport model. The simulation results quantify the heat transfer rate in the plasma plume, heat losses due to radiation, and variations of heat input into the material.