Novel fusion welding technology of glass using ultrashort pulse lasers

A novel fusion welding technology of glass using ultrashort laser pulses with high pulse repetition rates has been developed, where the laser energy is selectively absorbed at the interface by nonlinear process to provide crack-free welding without preand post-heating. A laser-matter interaction model is developed to evaluate the distribution of the ultrashort pulse laser energy absorbed in bulk glass. A thermal conduction equation is derived to calculate transient 3-dimensional temperature distribution and dimensions of molten zone in glass. The mechanical strength of weld joint is evaluated taking into consideration of the attracting force of the optical contact between the glass plates needed for keeping the high-temperature plasma in the bulk glass.