Efficiency of various mechanisms of the laser damage in transparent solids

Criteria for the laser damage in transparent solids are compared for different mechanisms of radiation absorption. It is shown that the most efficient mechanism of laser damage in a broad range of pulse durations (from millisecond to femtosecond laser pulses) is the photoionisation thermal explosion of absorbing inclusions. It is found that upon irradiation by long laser pulses, the damage proceeds through a melting stage. A fundamental feature of the damage is that, to produce a crack in a transparent solid, the size of an absorbing region should exceed a critical size.