Methods of investigating the role of absorbing microinclusions in damage to transparent dielectrics by laser radiation. I - Passive methods
Methods are considered for investigating absorbing inclusions of dimensions di3×10−5cm in transparent dielectrics. A quantitative criterion is proposed for discriminating between inclusions in respect of their size determined by investigation of light scattering. An ultramicroscopic method of measuring the sizedistribution function of inclusions of diameter di~10−6–3×10−5 cm in the bulk of a transparent dielectric was proposed, tested experimentally, and appled to the industrial glasses K8 and TF5 and to liquating Na-7-B-23 glass. It is shown that all these glasses contain inhomogeneities of di~10−6–10−5 cm size, with a concentration of 1011 cm-3, whereas the concentration of inhomogeneities of di3×10−5 cm size does not exceed 3×106 cm−3. Plots are made of the size-distribution functions of the inclusions in these glasses.