Abstract

As has been shown,¹ the precision, with which the threshold of laser-induced breakdown (LIB) can be determined, increases dramatically as the pulse width of the laser decreases to picosecond and sub-picosecond regime. Also for ultrashort pulses the energy fluence needed to initiate breakdown is much less than the nanosecond pulse regime (see Fig. 1). In addition, picosecond and femtosecond laser pulses can deliver extremely localized heat to the target, because the thermal diffusion from the focal region, which caused the surrounding area to heat up, is negligible within the pulse duration.

© 1996 Optical Society of America