Relationship between the chemically inhomogeneous structure of glass and the optical breakdown threshold

It has been established that the optical breakdown threshold of glasses W_th is related to the Landau&ndashlaczek ratio R_L–P of the scattered-light spectrum. Published data and the results of measurements of the scattered-light spectra are used to obtain dependences of the relative optical breakdown threshold W_th on R_L–P for various Soviet and foreign glasses. It is found that W_th decreases as R_L–P increases. It is suggested that the role played by chemical and structural inhomogeneities in damage to glasses by high-power laser pulses should be taken into account. It is proposed that results of scattered-light spectroscopy should be used to search for glasses having high W_th.