Process for Removing Hydrogen and Carbon Impurities from Glasses by Adding a Tellurium Halide
Patent, Filed 26 Jun 96, patented 14 Jul 98
DEPARTMENT OF THE NAVY WASHINGTON DC
Pagination or Media Count:
Hydrogen andor carbon impurities are removed from chalcogenide or chalcohalide glasses by the addition of a halide, such as TeCl4, to the batch composition. During melting of the batch composition, the metal halide reacts with the hydrogen andor carbon impurities to form a hydrogen halide andor carbon tetrahalide gas and a metal which becomes incorporated into the chalcogen-based glass. Useful halides include halides of sulfur, selenium, tellurium, polonium, or halides of a metal such as aluminum, magnesium, zirconium, or a mixture thereof that forms a stable oxide. Mixed metal halides may also be used. The glass melt is then distilled, outgassed, homogenized, fined, and annealed. An apparatus specially designed for making a fiber preform by the above process is also described. An annealed preform made by this method may be drawn into a low-loss fiber in the 2 microns to 12 microns range.
- Inorganic Chemistry
- Fiber Optics and Integrated Optics