Abstract: A telluride glass with glass transition temperature above 150.degree. C., fference between the crystallization temperature and the glass transition temperature of above 200.degree. C., and extended transmission in the infrared region of radiation of up to 20 microns having, on mol basis, 20-60% tellurium, 10-50% arsenic, 4-35% germanium, 0.5-15% gallium, up to 15% iodine, and up to 30% selenium. All or part of the gallium can be replaced with indium and the glass can contain up to 5%, based on the weight of the glass components, of a rare earth ion to render the glass fluorescent. Optical fibers drawn from these glasses have shown mid infrared fluorescence and may have as a bright source of IR light.

Abstract: A selenide glass with improved mechanical and optical properties such as ended transmission in the infrared region of radiation having wavelengths beyond 15 microns; Tg in the region of 363.degree.-394.degree. C.; and thermal stability of 85.degree.-145.degree. C. based on the difference between T.sub.g and T.sub.x, comprising, on mol basis, 20-70% germanium selenide, 0.5-25% gallium selenide, indium selenide or mixtures thereof; and 5-50% of at least one alkaline earth in selenide form is described. A process for improving mechanical and optical properties of a selenide glass based on germanium selenide comprises the steps of mixing glass components, including a modifier in elemental or selenide form; melting the glass components to form a molten mixture; cooling the molten glass mixture to a solid state; annealing the solid glass; and cooling the annealed glass to about room temperature is also described.

Abstract: A glass-ceramic article or composition which has better thermal and physical properties than the competing materials of zinc sulfide, spinel, or magnesium fluoride comprising 2-30 mole percent yttrium oxide and/or rare earth oxide, 25-80 mole percent germanium oxide, and 5-30 mole percent gallium oxide, based on the total moles of yttrium oxide and/or the rare earth oxide, germanium oxide, and gallium oxide; which article is over 80% by volume crystalline.

Abstract: A preferred embodiment of a sulfide glass with improved mechanical and optical properties such as extended transmission in the infrared region of radiation having wavelengths of up to about 15 microns, Tg in the range of 370.degree.-550.degree. C., and thermal stability of 100.degree.-300.degree. C., containing, on mol basis, 36-72% germanium sulfide, 2-38% gallium sulfide and/or indium sulfide, and 26-62% of at least one modifier containing an alkaline earth sulfide. A process for making glass of improved mechanical and optical properties comprises the steps of mixing glass components, including an alkaline earth modifier in elemental or sulfide form; melting the glass components in an inert vessel contained in a sealed ampoule to form a molten mixture; cooling the molten glass mixture to a solid state; annealing the solid glass; and cooling the annealed glass to about room temperature.

Abstract: A sulfide glass with improved mechanical and optical properties such as ended transmission in the infrared region of radiation having wavelengths of up to about 15 microns; Tg in the region of 410.degree.-550.degree. C.; and thermal stability of 100.degree.-300.degree. C. based on the difference between T.sub.g and T.sub.x, comprising, on mol basis, 20-90% germanium sulfide, 0-60% gallium sulfide, and 5-60% of at least one modifier in sulfide form. A process for improving mechanical and optical properties of a sulfide glass based on gallium sulfide and/or germanium sulfide comprises the steps of mixing glass components, including a modifier in elemental or sulfide form; melting the glass components to form a molten mixture; cooling the molten glass mixture to a solid state; annealing the solid glass; and cooling the annealed glass to about room temperature.

Abstract: A germanate glass ceramic article which has better thermal and physical perties than the competing materials of zinc sulfide, spinel, and sapphire is made by mixing germanate ceramic glass components; melting the components to form a molten mass; cooling the molten mass to form a solid glass article; nucleating the solid article by heating it in the range of about 630.degree.-790.degree. C. for about 1-16 hours to develop nuclei in the article; and crystallizing the nucleated article by heating it, after nucleation, in the range of about 1/2 minute to about 8 hours to grow the nuclei to crystallites having an average diameter of less then about 1000 nanometer (nm); and cooling to form the glass ceramic.

Abstract: A method for producing internally coated glass tube preforms for drawing er optic conductors. The internally coated glass tubes are halogen coated, preferably coated with metal fluorides, so that an optical fiber formed will have a halogen core which conveys light having a wavelength of about 2 to 4 microns, which is in the infrared region, with low attenuation. With one aspect of the method, a carrier gas and a halogenated alkoxide are introduced into a glass tube which has an inner wall and which is surrounded by a resonator for producing a plasma from the halogenated alkoxide in the tube. With another aspect of the method, a blend of a carrier gas, an organometallic compound, and a halogen-containing gas are introduced into a glass tube which has an inner wall and which is surrounded by a resonator for producing a plasma. In both cases, the tube is moved relative to the resonator to form a plasma zone within the tube such that a halide coating is formed on the inner wall of the tube.

Abstract: Defect-free fluoride glass materials are made by hot isostatic pressing (HIP) of a fluoride glass. The process may be used to manufacture preforms or bulk fluoride glass. The external pressure applied during HIP squeezes bubbles from the glass and permits the use of a wider range of working temperatures than ordinarily available, thereby reducing crystallization defects.

Abstract: A hermetically sealed optical fiber product comprising a fluoride or other non-silica based glass optical fiber and a hermetic coating of carbon, a metal, a fluoride, a metalloid or a ceramic compound in a thickness sufficient to impart moisture resistance to the optical fiber product.