Halide Glasses

This article outlines the wide range of glass compositions in halide systems and their characteristics. Single halides such as BeF 2 , ZnCl 2 , ZnBr 2 and PbI 2 exist in the vitreous state. Fluorozirconate glasses were the basis for numerous studies of other halide and polyhalide glasses fluorohalides and mixed heavy halides. Fluoride glasses have been more extensively studied and developed. In a first step the prospect for long haul and low optical losses attracted significant interest. Later, optical fibers appeared to be complementary to silica fibers for infrared transmission and fiber lasers. Some examples of these glasses and the optical characteristics are given. In spite of their potential for infrared technologies, heavy halide glasses have been less developed, mainly because of problems of stability in moist atmosphere. New encapsulation techniques could open promising perspectives.