Corning Glass Works

Thomas P Seward, Iii

Nicholas Francis Borrelli

Roger J Araujo

David L Morse

George Bigelow Hares

David J Kerko

Jean P Mazeau

John D Crow

Jan B Chodak

Gerald S Meiling

Daniel Aloysius Nolan

Paul A Tick

Brent M Wedding

Frank Thomas Coppola

Dennis W Smith

William P Lentz

George C Shay

Paul I Kingsbury

Nicholas F Borelli

A method is set forth for making polarizing glasses having high dichroic ratios by drawing relatively small silver-containing particles under relatively high stress and elongating such particles during the drawing process without rupturing the glass draw by coating the polarizing glass with a substantially low viscosity skin glass.

Drawing laminated polarizing glasses

The instant invention is directed to the preparation of glass articles exhibiting excellent polarization in the infrared portion of the spectrum from glasses characterized as containing silver halide particles therein selected from the group of AgCl, AgBr, AgI. The inventive method comprises four general steps:

Infrared polarizing glasses

The instant invention is related to the manufacture of photochromic glasses having base compositions within a very narrow interval of the alkali metal boroaluminosilicate system wherein silver chloride and/or silver bromide crystals impart photochromic properties. The glasses are notable for their rapid fading characteristics and relatively low temperature dependence of darkening. The compositions are especially suitable for a production process which contemplates simultaneously shaping articles from glass sheet and developing photochromic properties therein.

Method of making photochromic glasses suitable for simultaneous heat

Silver-free, cadmium-free, copper halide-based alkali aluminoborosilicate glasses exhibiting good optical clarity and good photochromic darkening and fading are provided by controlling the alkali, Al.sub.2 O.sub.3 and B.sub.2 O.sub.3 concentrations in the base glass and/or adding MoO.sub.3 or WO.sub.3 thereto.

Optically clear copper halide photochromic glass articles

A fluorine containing silicate glass substrate is heated to a temperature sufficiently high to permit fluorine to out-diffuse from the surface thereof. A surface region is formed having a gradient fluorine concentration in a direction perpendicular to the substrate surface, the region of lowest fluorine concentration having the highest refractive index. The resultant device is capable of functioning as an optical waveguide.

Fluorine out-diffused optical device and method

The instant invention is concerned with transparent photochromic glass compositions which not only exhibit desirably rapid darkening and fading characteristics, but which also demonstrate the other physical and optical properties required for use in ophthalmic applications. Such glasses utilize the presence of silver chloride and/or silver bromide crystals to impart photochromic behavior in a narrowly-defined composition range within the alkali metal aluminoborosilicate base system. Copper ions are also included in the composition to perform as a sensitizing agent. The glasses have the capability of being either thermally tempered or chemically strengthened to comply with the United States Food and Drug Administration regulations for lenses used in ophthalmic applications. Improved independence of temperature effects upon the photochromic properties can be achieved where the copper level, expressed as CuO, is maintained between about 0.004-0.02% by weight, the chloride value, expressed as Cl, is held between about 0.1-0.25% by weight, the silver content, expressed as Ag, is included between about 0.15-0.3% by weight, and the quantity of bromide, expressed as Br, is varied between about 0.1-0.2% by weight. The fading rate of the glasses is enhanced by maintaining the molar ratio of alkali metal oxides to B.sub.2 O.sub.3 between about 0.55-0.85, the molar ratio of alkali metal oxides minus Al.sub.2 O.sub.3 to B.sub.2 O.sub.3 is about 0.25-0.4, and the weight ratio Ag:(Cl+Br) is about 0.65-0.95.

Photochromic glass

A process for the production of a gradient photochromic glass article comprising the selective over-nucleation of a limited portion of the article followed by a photochromic development heat treatment of the entire article, and the product of this process, are described.

Process for making gradient photochromic glass articles

Chemically-strengthenable silver halide-containing lithium boroaluminosilicate glass compositions having physical and chemical characteristics required for sheet drawing processes and exhibiting excellent photochromic properties after heat treatment, and also strengthened photochromic drawn sheet glass articles provided therefrom, are described.

Photochromic sheet glass compositions and method

Photochromic glasses suitable for simultaneous heat treatment and shaping

The absorptive and refractive properties of additively colored glasses containing an absorptive metallic silver phase and a separated silver halide phase are altered by irradiating the colored glasses with visible light. Polarization effects and multicolored images can be produced.

Colored, dichroic, birefringent glass articles produced by optical

Silver halide-containing photochromic glasses are rendered optically anisotropic by darkening with actinic radiation and irradiating with linearly polarized bleaching light. A photochromic glass so treated will be optically isotropic when it returns to the clear state, but may again become optically anisotropic when redarkened. Color adaptation results when darkened silver halide-containing photochromic glasses are irradiated with colored optical bleaching light.

Photochromic glasses exhibiting dichroism, birefringence and color

The present invention is directed to a method for producing patterned color-triad arrays in glass for use in color television picture tubes, such arrays being capable of acting as spectrally-selective filters and to provide the desired color information when the television tube is operating. The color-triad arrays are produced by sequentially or simultaneously exposing a polychromatic glass through an electron shadow mask to high energy or actinic radiation and thereafter following the heat treatment and re-exposure practice known to develop colors within polychromatic glass. The filtering action provided by the color triads integrally present within the glass can enhance the contrast of the color image produced. Also, the presence of the color triads in the glass permits the use of a single 'white' phosphor, rather than a red, a green and a blue phosphor as are presently used in the conventional color television picture tube.

Method for producing tri-color screens for television picture tubes

A method and system for processing a photographic negative to obtain photographic prints exhibiting enhanced contrast therefrom are described. A sheet of darkened optically bleachable photochromic glass, positioned between the negative and a selected photographic printing medium, is selectively bleached by light passing through the negative to form an image of the negative in the glass. Light of a wavelength effective to activate the photographic printing medium is then passed through the photographic negative and selectively bleached photochromic glass and focused to provide an enhanced contrast image of the photographic negative on the printing medium. A photographic print of enhanced contrast is thus produced.

Growing community of inventors

Corning, NY, United States of America

Thomas P Seward, Iii