Inverse problem of laser breakdown statistics

Methods are developed for obtaining stable solutions of the inverse problem of laser breakdown of transparent media containing microdefects. A method is suggested for constructing the function describing the breakdown probability density directly in terms of experimentally determined levels of cutoff of pulses transmitted by a medium. This method is used to obtain a practical algorithm for reconstructing the dependence of the concentration of microdefects on the threshold intensity needed for the initiation of breakdown. The logarithm is applied, by way of a demonstration, to an investigation of the defect structure of a sapphire crystal.