Abstract: The invention relates to novel benzopyran-type compounds having an aromatic heterocycle annelated in position 7,8 and a carbocycle annelated in position 5,6. These compounds have the formula (I) given below: These compounds (I) have interesting photochromic properties. The invention also relates to their preparation, to their applications as photochromes, as well as to the compositions and (co)polymer matrices containing them.

Abstract: Lenses for use with electronic imaging systems, e.g., systems employing CCDs, are provided. The lenses employ at least two lens elements, at least one of which is a dyed plastic lens element whose average percentage transmission for wavelengths between 400 nm and 550 nm is greater than its average percentage transmission for wavelengths between 550 nm and 700 nm. Through the use of such a dyed plastic lens element, the need for a separate spectral response flattening filter is eliminated thus reducing the cost, complexity, size, and weight of the electronic imaging system.

Abstract: The present invention relates to novel compounds of the naphthopyran type which have a perfluoroalkyl group (X) in position 5. These compounds are of formula (I) given below: These compounds (I) possess interesting photochromic properties. The invention also relates to their preparation, their applications as photochromes as well as the compositions and matrices containing them.

Abstract: The invention relates to photochromic transparent organic materials particularly useful for the production of photochromic organic ophthalmic lenses. The material includes an optical-quality polymer matrix and at least one coloring agent giving photochromic properties to the matrix. The coloring agent is chosen from the group of the spirooxazins the spiropyrans, and the chromenes. The polymer of the matrix is chosen from the group of homopolymers of ethyoxylated bisphenol A dimethacrylate with formula I: in which R is H or CH3, and m and n independently represent 1 or 2, and of the copolymers of this dimethacrylate containing at most 30 wt % of an aromatic monomer with vinyl, acrylic or methacrylic functionality.

Abstract: For subject, the present invention has novel naphthopyran derivatives of formula: optionally substituted in position(s) 2, 3, 4, 6, 7, 8, 9 or/and 10; the substituent Z in position 5 being of formula —C(R1)(R2)(OR3). The invention also relates to compositions and (co)polymer matrices containing such derivatives. Said derivatives have interesting photochromic properties.

Abstract: An inspection system for and a method of inspecting defects on opposite sides of a glass specimen are set forth wherein a focusing filament is positioned in the light path of an inspection system having an objective lens. The filament is focused to the same plane that the objective lens uses to image a defect on the glass surface, so as to produce a shadow of the filament in the field of view when the objective is focused on either a front or back surface of the specimen. The utilization of the focusing filament provides an absolute surface reference that can automatically compensate for variations of the glass specimen position relative to a plane.

Abstract: The object of the present invention is novel photochromic [indole]naphthopyran compounds and their methods of preparation.

Abstract: The present invention is directed to chromophores having novel electron withdrawing groups and novel bivalent cyclic bridges and to optical waveguides and optical devices having polymeric thin films which contain the novel chromophores.

Abstract: A method of stabilizing a glass-ceramic body, particularly an aluminosilicate body, for use as a telecommunications component in a humid atmosphere, comprises coating the body with an aqueous solution of an alkali metasilicate, with a solution of a silane that is strongly non-polar with respect to water, or with successive applications of the metasilicate and the silane.

Abstract: A non-porous, transparent glass-ceramic body that is consolidated from a predominately silica-based preform (SiO2+GeO2 85-99.0 wt. %) containing rare earth fluoride crystals embedded within by solution chemistry. The glass ceramic body is suited for making fibers for optical amplifiers.

Abstract: Methods for temporarily protecting a surface of a glass article by coating the surface are provided. The methods include forming a stable, hydrophobic, removable film on the surface at the end of the glass manufacturing process while the glass is still at an elevated temperature (e.g., above 175° C.). The film reduces chip adhesion to the surface as a result of cutting and grinding. After cutting and grinding, the film is removed allowing the glass to be used in such processes as the manufacture of liquid crystal displays (LCDs).

Abstract: The invention relates to novel naphthopyran-type compounds having a lactam-type 6-membered ring annelated in position C5-C6. These compounds have the formula (I) given below: These compounds (I) have interesting photochromic properties. The invention also relates to their preparation, to their applications as photochromes, as well as to the compositions and (co)polymer matrices containing them.

Abstract: A lead silicate glass frit composition particularly useful for the formation of dielectric layers and barrier ribs in plasma display panels.

Abstract: A method for edge finishing glass sheets. Glass sheets are separated into desired sizes, after which the edges of the glass sheets are finished using first grinding wheels to grind the edges, followed by polishing wheels to round off the ground edges by contacting and moving the edges of the glass sheet against stationary rotating grinding and polishing wheels which are each oriented approximately parallel to the major surface of the glass sheet.

Abstract: A polishing application uses alkali, colloidal silica for polishing silicate-based glasses. Preferably, the silica solutions are adjusted to a pH of or above 10. The polished silicate-based glass surfaces have surface finishes consistently below 2 Å Ra. The unique method first polishes a surface of the substrate with an aqueous solution of at least one metal oxide abrasive and further polishes the surface of the substrate with an alkali aqueous solution of colloidal silica. Preferably, to the final smoothness of 2 Å Ra or less.

Abstract: An assembly of rib structures sandwiched between a dielectric glass layer and a glass substrate for use in a flat panel display, such as plasma addressed liquid crystal (PALC) displays, is formed by a number of methods. One method includes molding thermoplastic glass frit containing paste into rib structures, transferring the rib structures to a thin transparent layer of a thermoplastic dielectric glass frit containing composition on a drum, and transferring the rib structures with the thin transparent dielectric glass layer to a glass substrate having metallic electrodes already formed thereon.

Abstract: Fused silica boules (19) having improved radial homogeneity are produced by controlling the air flow around the boule (19) during its formation. The boule is formed in a cup-like containment vessel (13) which collects silica particles from a plurality of burners (14). The containment vessel (13) rotates and oscillates relative to the burners (14) as the boule (19) is formed. The containment vessel (13) is bounded by a cup-like containment wall (22), and a shadow or air flow wall (130) is spaced apart from and surrounds the containment wall (22) forming a gap or air flow passage (175) therebetween. A radially-outwardly extending deflecting wedge portion (23) is formed at the upper extent of the containment wall (22) and at an outlet end of flow passage (175).

Abstract: The objects of the present invention are: a self-light-stabilized photochromic thermoplastic or thermoreticulated polymer carrying non-cyclic tertiary amide-functionalized pendant groups; its preparation method; photochromic articles constituted, wholly or in part of such a polymer. Said polymer is obtained advantageously by radical co-polymerization of a composition containing an effective amount of at least one monomer of the formula: in which: R1 is hydrogen or a methyl group; n is 2 or 3; R2 and R3 are identical or different and represent independently a methyl or ethyl group; and are advantageously identical; said monomer providing said photostabilizing non-cyclic tertiary amine-functionalized pendant groups.

Abstract: A fused silica refractory material made from quartz grains and a method of making the material which contains calcium oxide binder in an amount less than one weight percent. The reduction in calcium oxide binder prevents the degradation of fused silica refractory bricks in furnace environments containing alkali vapors, such as in oxygen-fuel fired glass furnaces. The invention also includes a method of preventing the degradation of silica refractory material by alkalis.

Abstract: A copolymer containing N-(halogenated phenyl) maleimide units or N-(halogenated phenyl) bismaleimide units and one or more second units selected from halogenated acrylates, halogenated styrenes, halogenated vinyl ether, halogenated olefins, halogenated vinyl isocyanates, halogenated N-vinyl amides, halogenated allyls, halogenated propenyl ethers, halogenated methacrylates, halogenated maleates, halogenated itaconates, and halogenated crotonates, is useful to form optical devices