Statistics of laser damage to the surface of lithium niobate

An analysis is made of the density of the distribution of the laser strength over the surface of lithium niobate. It is shown that distributions of this kind are polymodal due to the presence of defects of several different types with different damage thresholds. The distribution of the laser strength on the surface of one sample, representing defects of one kind, can be described by the Weibull law. The overall (net) distribution is a random mixture of such partial contributions. In the case of a small dispersion of the weights of the partial distributions, the overall distribution can be described also–with some approximation–by the Weibull law.