Optical applications of glass-ceramics

Glass-ceramics are usually formed through passing several stages of phase transformations (nucleation, crystallization of metastable and stable crystalline phases). The properties of glass-ceramics depend on at what stage the process was stopped. The phase assemblage of glass-ceramics is controlled by the composition of the initial glass and heat-treatment conditions. Raman and optical spectroscopy, in combination with X-ray diffraction and small angle X-ray scattering techniques are used to study the behavior of the nucleation and crystallization of lithium, magnesium and zinc aluminosilicate glasses. Specific heat-treatments has given the opportunity to achieve a desired phase assemblage ensuring unique properties of glass-ceramics by interrupting the process at a certain stage.Examples of such glass-ceramic developments include thermal shock resistant color filters, passive Q-switchers for eye-safe Er:glass lasers, as well as transparent materials based on rare-earth titanates with pyrochlore structure with luminescence in the range of 1.5 μm. The approach to developing the dual active–passive media for the eye-safe spectral region is demonstrated for the first time.