An optical device of determining the local characteristics of crystals by means of counterpropagating laser beams

摘要

An optical device designed for nondestructive quality control and measurements of local characteristics in bulks of crystals and other optical elements with a spatial resolution of the order of 0.1 mm is described. The parameters determined experimentally are the concentration of impurity ions, the coefficient of scattering at an angle of 900, and the light extinction coefficient within local regions. The operating principle of the device is based on the fluorescent method of counterpropagating laser beams. The distributions of characteristics along the lengths of LiYF{sub}4：Er{sup}(3+) and LiYF{sub}4 : Nd{sup}(3+) crystals are studied.