Abstract: Optical fibers comprising core and/or cladding elements composed of MgO--Al.sub.2 O.sub.3 --SiO.sub.2 glasses are described wherein control of thermal expansion mismatch among the core and cladding elements is possible. Low-stress, high numerical aperture fibers as well as prestressed polarization-relating and high strength fibers are described.

Abstract: Tetrasilicic fluormica glass-ceramic compositions particularly suited for use in the preparation of dental restorations, consisting essentially in weight percent of about 45-70% SiO.sub.2, 13-30% MgO, 5-20% K.sub.2 O, 0-2% Al.sub.2 O.sub.3, 0-7% ZrO.sub.2, 4-9% F and 1-4% BaO, and porcelain-glazed dental restorations prepared therefrom, are described.

Abstract: A method for producing sodium-containing glasses, by a vapor deposition process wherein a vapor mixture containing a sodium fluoroalkoxide compound is reacted to provide a particulate sodium-containing vapor deposition product which can be sintered to a glass.

Abstract: Glass preforms for optical fibers or the like having refractive index profiles which vary in stepped or graded fashion across the preform, are made from porous glass preforms by introducing a first dopant into the porous preform during manufacture, partially sintering the preform to selectively modify the internal surface area thereof, introducing a second vapor-infusible dopant into the selectively sintered preform to cause selective doping of the porous glass, and then consolidating the resulting doped preform to clear glass.

Abstract: In the manufacture of preforms for metal halide optical fibers by the vapor deposition of metal halide layers on the inside surface of a silicate glass substrate tube, silicon release from the tube side wall by fluorine-containing reactants used in the vapor deposition process is reduced by the preliminary application of a slurry coating of a sinterable, fluorine-resistant metal halide or other glass composition which is dried and sintered to a passivation layer.

Abstract: Photochromic glass compositions for thin refractive-index-corrected lens elements consisting essentially of about:______________________________________ SiO.sub.2 54-58% B.sub.2 O.sub.3 18-22% Al.sub.2 O.sub.3 7-8% Li.sub.2 O 3.75-4.5% Na.sub.2 O 0-1% K.sub.2 O 5.5-7.5% TiO.sub.2 0-2% ZrO.sub.2 2-4.5% Ag 0.20-0.33% Cl 0.30-0.50% Br 0.04-0.12% CuO 0.007-0.012% PbO 0-0.08% Sb.sub.2 O.sub.3 0-0.20% ______________________________________having a Li.sub.2 O:Na.sub.2 O molar ratio of at least 9:1 and exhibiting good darkening, fast fading, good chemical strengthenability and neutral dark-state coloration at thicknesses on the order of 1 mm, are described.

Abstract: A vapor phase method for the synthesis of MgO--Al.sub.2 O.sub.3 --SiO.sub.2 products, including MgO--Al.sub.2 O.sub.3 --SiO.sub.2 glasses of optical quality, wherein SiCl.sub.4, aluminum halide, and organometallic magnesium vapors are oxidized by flame oxidation and the oxides collected and sintered to glass or ceramic products, is described. A added shield gas stream is provided during flame oxidation of the vapors to reduce or prevent MgCl.sub.2 by-product formation at the burner and in the product.

Abstract: Suspensions of particulate oxides, e.g., fumed silica, are prepared in non-aqueous media and the suspensions are used to cast shapes for glass or ceramic products. The suspensions are formed and then caused to gel by means of an added gelling agent, and thereafter dried and, optionally, sintered to transparent glass or void-free ceramic products.

Abstract: Apparatus and a method for splicing optical waveguide fibers to achieve a splice with minimum attenuation wherein light providing an alignment signal is inserted through the cladding and into the core of a first end section, transmitted into the core of the second end section, and extracted from and monitored at the second end section, with splicing being accomplished after the ends have been moved to a position providing an intensity maximum in the extracted signal.

Abstract: In the process of making a glass or ceramic article by the preparation of a non-aqueous oxide suspension of submicron oxide particles which is thereafter cast into a configuration for the product, gelled, dried, and fired to provide the unitary product, the need to thermally dry and/or protect the oxides from water contamination is avoided by treating the oxide with an alcohol to render it hydrophobic. The desirable gelling and drying characteristics of the suspensions are preserved.

Abstract: Powdered oxides to be processed into glass or ceramic products by suspension in organic vehicles, followed by gelling and drying the suspensions and sintering the oxides to unitary products, are pretreated prior to incorporation in the suspension with a ketal drying agent. The pretreatment removes adsorbed water and surface hydroxyl groups from the articles, improving their dispersion properties and the properties of the resulting suspensions.

Abstract: Novel adducts of magnesium and zinc .beta.-diketonates with the bidentate ether 1,2-dimethoxyethane are disclosed which exhibit high vapor pressures upon moderate heating, and improved resistance to thermal decomposition at vaporization temperatures.

Abstract: Novel halide glass-forming compositions in the CdF.sub.2 -AlF.sub.3 -PbF.sub.2 and CdF.sub.2 -AlF.sub.3 -PbF.sub.2 -LiF composition fields are disclosed which exhibit unusual glass stability. The constituents of these glasses are potentially vapor transportable, so that very pure glass articles exhibiting excellent infrared transparency can be envisioned.

Abstract: Novel .beta.-diketonate complexes incorporating a tetrahydrofuran adduct, having the formula M(hfa).sub.2.nTHF wherein M is Mg or Zn and n is in the range of about 1-4 and, which offer high volatility and good chemical stability at vaporization temperatures, are described.

Abstract: A method for the synthesis of tetrakis-(6,6,7,7,8,8,8,-heptafluoro-2,2-dimethyl-3,5-octanedione) cerium (IV), [Ce(fod).sub.4 ] wherein the product is directly formed by reacting the deprotonated beta-diketonate ligand with a cerium (IV) salt, is disclosed.

Abstract: Glass or ceramic products including glass optical waveguides are produced by a vapor phase oxidation process wherein .beta.-diketonate complexes of selected metals having significant vapor pressures at some temperature below their decomposition temperatures are vaporized, transported to an oxidation site in the vapor phase, and reacted in the vapor phase to form particulate metal oxide soot. After capture, this soot can be consolidated by sintering to form e.g. clear glass of a purity suitable for drawing into glass optical waveguide fiber.

Abstract: Novel .beta.-diketonate complexes incorporating a tetrahydrofuran adduct, having the formula M(hfa).sub.2.nTHF wherein M is Mg or Zn and n is in the range of about 1-4 and, which offer high volatility and good chemical stability at vaporization temperatures, are described.

Abstract: Colored photochromic ophthalmic lenses are produced by combining a photochromic cap element having an integrally colored back surface with an ophthalmic crown base element having a prescription-ground back surface, the cap back and base element front surfaces having been finished to a matching standard base curvature, thus providing a cemented assembly exhibiting a selected combination of prescribed vision-correcting and light filtering properties.

Abstract: An electrochromic device comprising a solid electrolyte, wherein the electrolyte consists of porous glass impregnated with a solid ion-conductive compound such as an alkali metal salt, is described.

Abstract: Spherical singlet lenses of gradient index design, suitable for use as video disk lenses or the like, are provided wherein all orders of spherical abberation are sufficiently reduced to provide diffraction-limited axial imaging. This imaging is achieved without resorting to sixth-order refractive index profile control; only the profile parameters N.sub.00, N.sub.10 and N.sub.20 defining the radial index profile N(r) in the profile function:N(r)=N.sub.00 +N.sub.10 r.sup.2 +N.sub.20 r.sup.2together with the surface curvatures and thickness of the lens, are used to control lens properties.