Some aspects of glass science evolution

Abstract

The development of halide glasses gives rise to several problems. From a basic point of view, the occurrence of glasses in numerous unexpected systems makes the prediction of glass forming ability a matter of reflection. An approach which encompasses kinetical, thermodynamical and structural aspects would be helpful for further investigations. Progress may be expected from computer simulations and calculations. Surface problems appear to be critical in various aspects of fluoride glass technology. They include hydrolysis, phase separation and diffusion processes. Finally, the reduction of the impurity level will be a major problem with respect to the manufacturing of ultra low loss optical fibers. During the next twenty years, numerous new glass forming systems will be investigated. Heavy metal oxide glasses will be synthesized. Increasing contents of nitrogen will be incorporated in glasses. New halide glasses will be discovered, especially in chloride, bromide, and mixed halide systems. Materials will be developed for optical transmission beyond 10 μm. Optical fibres lower than 10 −2 dB/km in attenuation will be achieved. BeF 2 fibres will be used for UV transmission. New sources and detectors will be available in the medium infrared range. Finally, new data and new concepts will provide a better understanding of glass structure, devitrification processes and optical losses.