Abstract: Non-oxide or heavy metal fluoride glass optical fiber with or without a cladding and coated with an outer layer of an oxide glass having a glass transition temperature of less than 400.degree. C. and a thermal expansion coefficient of less than about 19.times.10.sup.-6.C.sup.-1. Also, a method of making and providing such coatings on non-oxide or fluoride glass, and fiber optic products prepared by such methods.

Abstract: Non-oxide or heavy metal fluoride glass optical fiber with or without a cladding and coated with an outer layer of an oxide glass having a glass transition temperature of less than 400.degree. C. and a thermal expansion coefficient of less than about 19.times.10.sup.-6 .degree. C..sup.-1. Also, a method of making and providing such coatings on non-oxide or fluoride glass, and fiber optic products prepared by such methods.

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.

Abstract: A method for hermetically sealing a silica based fiber product after the fiber product has been drawn from a melt or preform wherein a hermetic layer of boron carbide or a ceramic compound having a density of above about 4 g/cc is deposited upon the fiber product. The fiber product can be initially coated with carbon or boron carbide prior to the application of the ceramic compound. Also, a method for making such fiber products using these methods, and the resultant hermetically sealed fiber products produced thereby.

Abstract: This invention relates to the production of mirror blanks comprising a low expansion graphite or SiC fiber reinforced glass-ceramic composite substrate with a surface facing of a glass or glass-ceramic bonded thereto having an expansion closely matching that of the composite.

Abstract: A glass optical waveguide preform is formed by chemical reaction of gaseous and/or vaporized ingredients within a glass substrate tube. A reactant feed tube extends into a first end of the substrate tube. One of the reactants flows through the feed tube, and another flows through the annular channel between the feed and substrate tubes. The reactants combine just downstream of the end of the feed tube and react to form particulate material, at least a portion of which deposit in the substrate tube. The output end of the feed tube traverses the substrate tube so that the region of maximum soot deposition moves along the length of the substrate tube. A hot zone traverses the substrate tube in synchronism with the feed tube to sinter the deposited soot.

Abstract: This invention is directed to the production of fused silica-containing glass articles of large cross section or diameter wherein at least a surface layer thereof exhibits very high optical quality. The method involves depositing via flame hydrolysis/oxidation reaction a layer of fused silica-containing soot onto a supporting bait, essentially immediately thereafter applying a source of heat concentrated uniformly across the breadth of the soot deposit, but focused only over a relatively small area thereof, to raise the temperature within that area sufficiently to uniformly consolidate the soot in that area into a non-porous glass, and then cooling the glass to room temperature.

Abstract: A method of incorporating an additive or dopant oxide into a glass body produced by the oxidation of vaporous source material in a flame. The resultant glassy particles are deposited to form a porous preform having a uniform refractive index. During the consolidation process, the preform is subjected to an atmosphere including a drying agent which penetrates the interstices of the soot preform to simultaneously dry and dope the preform.

Abstract: A method of forming a preform or blank for an optical filament, the preform itself and the resulting optical filament is disclosed. The preform is formed by providing a substantially longitudinally continuous core member and affixing it to a starting member. Particulate material is applied to the exterior surface of the core member to form an adherent coating having an index of refraction less than that of the core member. The starting member and the core member are longitudinally translated while simultaneously applying the adherent coating of particulate material to the core member to form a continuous and substantially homogeneous adherent coating of substantially uniform thickness.

Abstract: A method of forming graded index, nitrogen-doped optical waveguides. A cylindrically-shaped porous preform comprising at least two oxides is initially formed. One of the oxides, which more readily reacts with nitrogen, has a greater concentration near the center of the preform than at the outer portion thereof. The preform is treated with a nitrogen-containing compound to form a porous body having a greater concentration of nitrogen in the central portion thereof. The porous preform is consolidated and drawn into an optical waveguide filament.

Abstract: Fused oxide type glasses produced by flame hydrolysis are described. These glasses are composed of P.sub.2 O.sub.5 and, optionally, SiO.sub.2. P.sub.2 O.sub.5 is present in an amount of at least 2% by weight.

Abstract: A composite glass article is disclosed that is composed of a TiO.sub.2 --Al.sub.2 O.sub.3 --SiO.sub.2 glass core portion encompassed within a compressively stressed, vitreous silica-type glass exterior portion. The composite is strengthened by heat treatment within the ranges of 600.degree.C. to 900.degree.C. to effect a non-reversible contraction of the core glass at temperatures below the lowest glass strain point.

Abstract: A method of producing a planar optical waveguide by applying to at least a portion of one flat surface of a substantially flat glass substrate having a predetermined desired index of refraction a first coating of glass having an index of refraction greater than that of said glass substrate. Thereafter a second coating of glass having an index of refraction less than that of the first coating of glass is applied over the exposed surface of the first coating of glass. The thickness of the first coating of glass being determined as a function of the highest mode order and the wavelength of light to be propagated within a waveguide having infinite width, and the indices of refraction of the substrate and each of the applied coatings.