Formulation of the criterion of thermoelastic laser damage of transparent dielectrics and the dependence of the damage threshold on the pulse duration

An analysis of the thermoelastic problem is used to formulate the criterion of mechanical damage of a transparent dielectric by laser radiation. The criterion is suitable for calculation of the threshold characteristics of the damage associated with absorbing inclusions and that involving intrinsic mechanisms. It is shown that in the limit of short laser pulses the threshold energy density tends to a constant value for any radiation absorption mechanism. A study is reported of the dependence of the threshold of damage initiated by absorbing inclusions on the pulse duration in a wide range of pulse durations. The theoretical results are compared with the published experimental data.