Abstract: In a process for manufacture of dense, amorphous quartz glass granulate by production of a porous granulate from amorphous SiO2 powder and vitrification of the granulate, a porous SiO2 granulate is exposed to a fuel gas flame and is finely dispersed, heated and vitrified therein. The fuel gas flame is more flexible as concerns adjustment of the temperature than in known processes. It is in particular possible to set higher temperatures. The granulate can be exposed to very high sintering temperatures in the fuel gas flame without sintering into agglomerates. At the same time, heat resistance problems of sintering containers such as furnaces and melting pots are avoided. In addition, contamination of the SiO2 granulate by contact with the walls of sintering or vitrifying containers is eliminated. The process makes it possible to economically produce a highly pure and dense quartz glass granulate.

Abstract: The present invention relates generally to UV (ultraviolet) photosensitive bulk glass, and particularly to batch meltable alkali boro-alumino-silicate glasses. The photosensitive bulk glass of the invention exhibits photosensitivity to UV wavelengths below 250 nm.

Abstract: The application discloses a number of unique sintered quartz glass products together with new silica compositions and processes for making and using such products. Nitrided clear and opaque nitrided quartz products are disclosed having incredible physical properties resulting from the incorporation of very small, but effective, amounts (e.g., 25 ppm or more) of chemically bound nitrogen. Opaque quartz glass heat shields with remarkable resistance to transmission of infrared radiation are disclosed which can have a high bubble population density, such as 80 to 120 per mm2. These heat shields make possible remarkable improvement in the performance of tube furnaces and other reactors used in processing silicon wafers and other electronic components.

Abstract: The present invention provides a method for making a stain-resistant float glass and an apparatus for carrying out such a method. In keeping with this method, SO3 is applied to the upper surface of float glass in an amount efficacious to materially reduce staining of the upper surface of the glass. Optimally, SO3 gas can be applied directly onto the upper surface of the glass. An apparatus of the invention generally includes a downwardly open hood positioned above the upper surface of the glass and having walls defining an enclosure. SO3 gas (either as such or as a reactive mixture of S02 gas and an oxygen-containing gas) is delivered through a delivery tube to the enclosure.

Abstract: A method that provides a new way to embed rare earth fluorides into silicate (or germania-doped silica) glasses by means of solution chemistry. Embedding rare earth fluorides into a silicate (or germania-doped silica) glass comprises the following steps. First, form a porous silicate core preform. Second, submerge the preform into an aqueous solution of rare earth ions. Third, remove the preform from the solution and wash the outside surfaces of the preform. Fourth, submerge the preform into an aqueous solution of a fluorinating agent to precipitate rare earth trifluorides from the solution and deposit in the pores or on the wall of the preform. This is followed by drying.

Abstract: The present invention provides a method for making a stain-resistant float glass and an apparatus for carrying out such a method. In keeping with this method, SO3 is applied to the upper surface of float glass in an amount efficacious to materially reduce staining of the upper surface of the glass. Optimally, SO3 gas can be applied directly onto the upper surface of the glass. An apparatus of the invention generally includes a downwardly open hood positioned above the upper surface of the glass and having walls defining an enclosure. SO3 gas (either as such or as a reactive mixture of SO2 gas and an oxygen-containing gas) is delivered through a delivery tube to the enclosure.

Abstract: A silica glass is provided for use in an optical system processing an excimer laser beam. The silica glass has a molecular hydrogen concentration of about 5×1018 molecules/cm3 or less and is substantially free from defects which become precursors susceptible to an one-photon absorption process and a two-photon absorption process upon irradiation of the excimer laser beam to the silica glass.

Abstract: The present invention is a method of making a lithography photomask and photomask blank. The method of making the lithography photomask and photomask blank includes providing a silicon oxyfluoride glass tube having an OH content less than 50 ppm. The method further includes cutting the silicon oxyfluoride glass tube, flattening the silicon oxyfluoride glass tube, and forming the flattened cut silicon oxyfluoride glass tube into a photomask blank having a planar surface. The present invention includes a glass lithography mask preform. The glass lithography mask preform is a longitudinal silicon oxyfluoride glass tube that has an OH content ≦10 ppm, a F wt. % concentration ≧0.5 wt. %.

Abstract: Fused silica stepper lens for photolithographic application are disclosed which are resistant to laser-induced damage, specifically, compaction or densification which can lead to an increase in the optical path length of the lens. The figure compares the phase front distortions of a standard fused silica with the phase front distortions observed in two inventive stepper lens fused silica.

Abstract: Method is disclosed for making glass having both polarizing and non-polarizing regions integral thereto by either ion-exchange or by exposure to light and heat. The polarizing regions of the resulting glass is effective in polarizing light radiation, that is, the glass exhibits permanent dichroic behavior and has at least some polarizing effect in the wavelength range of 400 to 700 nm. The base glass composition contains Cu, Ag and at least one halide such that the resulting precipitated crystal phase consists of a halide.

Abstract: A method for manufacturing a synthesized silica glass optical member, the method comprising: providing a porous silica glass body; heating the porous silica glass body in an atmosphere containing hydrogen or oxygen, and sintering the porous silica glass body in an atmosphere containing fluorine compound. Furthermore, a synthesized silica glass optical member manufactured by the method.

Abstract: There is provided a quartz glass crucible for pulling a silicon single crystal and a production process for the crucible, wherein an inner surface of the crucible is crystallized without addition of impurities during pulling a silicon single crystal, thereby impurities serving as causes of crystal defects being not incorporated into the silicon single crystal, so that deterioration of its inner surface is suppressed to improve a crystallization ratio, and accordingly productivity of the quartz glass crucible as well as a quality of the silicon single crystal is improved, and the quartz glass crucible for pulling a silicon single crystal comprises a crucible base body (3) made of a translucent quartz glass layer and a synthetic quartz glass layer (4) formed on an inner wall surface of the crucible base body (3), wherein a portion encircled by a brown ring on an inner surface of the quartz glass crucible is uniformly crystallized during pulling the silicon single crystal.

Abstract: The present invention provides a method for manufacturing an optical component that have increased transmittance in the ultraviolet region of the spectrum. The method includes the steps of cutting out a part from a block material; polishing optical sides of the part; subjecting the part to heat treatment at a temperature of between 100 and 900° C.; and subjecting the part to acid treatment.

Abstract: The deposit of natural or synthetic silica comprises a preform (1) set into rotation (7) in front of a plasma torch (3) which moves back and forth substantially parallel to a longitudinal direction (L) of the preform (1), a feed duct (9) for feeding the plasma with grains of natural or synthetic silica (11), characterized in that the same feed duct (9) feeds the plasma with a fluorine or chlorine compound, preferably a fluorine compound, mixed with a carrier gas (15). Sodium or lithium contained in the grains of natural or synthetic silica reacts with the fluorine or chlorine of the fluorine or chlorine compound, making it possible to improve the optical quality of fibers built up with the natural or synthetic silica at reduced cost.

Abstract: The invention includes methods of making lithography photomask blanks. The invention also includes lithography photomask blanks and preforms for producing lithography photomask. The method of making a lithography photomask blank includes providing a soot deposition surface, producing SiO2 soot particles and projecting the SiO2 soot particles toward the soot deposition surface. The method includes successively depositing layers of the SiO2 soot particle on the deposition surface to form a coherent SiO2 porous glass preform body comprised of successive layers of the SiO2 soot particles and dehydrating the coherent SiO2 glass preform body to remove OH from the preform body. The SiO2 is exposed to and reacted with a fluorine containing compound and consolidated into a nonporous silicon oxyfluoride glass body with parallel layers of striae.

Abstract: A sheet of silicate glass having a thickness of 2 mm and composed mainly of SiO2, and containing Al2O3, B2O3, Na2O, F, etc., is immersed in a molten salt comprising a mixture of 50 mol % of silver nitrate and 50 mol % of sodium nitrate. Na ions in the surface of the glass are eluted, diffusing Ag ions in the molten salt into the glass. When a laser beam is applied to the glass substrate thus formed, the glass substrate is evaporated or ablated progressively from its surface. The glass substrate is processed to a smooth finish without causing cracking or breakage.

Abstract: High purity silicon oxyfluoride glass suitable for use as a photomask substrates for photolithography applications in the VUV wavelength region below 190 nm is disclosed. The inventive silicon oxyfluoride glass is transmissive at wavelengths around 157 nm, making it particularly useful as a photomask substrate at the 157 nm wavelength region. The inventive photomask substrate is a “dry,” silicon oxyfluoride glass which exhibits very high transmittance in the vacuum ultraviolet (VUV) wavelength region while maintaining the excellent thermal and physical properties generally associated with high purity fused silica. In addition to containing fluorine and having little or no OH content, the inventive silicon oxyfluoride glass suitable for use as a photomask substrate at 157 nm is also characterized by having less than 1×1017 molecules/cm3 of molecular hydrogen and low chlorine levels.

Abstract: Natural or synthetic silica is deposited on a preform set into rotation in front of a plasma torch which moves back and forth substantially parallel to a longitudinal direction of the preform, a first feed duct feeds the plasma with grains of natural or synthetic silica while a second feed duct feeds the plasma with a fluorine or chlorine compound, preferably a fluorine compound, mixed with a carrier gas Any sodium or lithium contained in the grains of natural or synthetic silica react with the fluorine or chlorine of the fluorine or chlorine compound, thereby making it possible to improve the optical quality of fibers drawn from a preform built up with natural or synthetic silica, and to do so at reduced cost.

Abstract: An athernal optical device and a method for producing the device, such as an athermal optical fiber reflective grating, are described. The athermal optical fiber reflective grating device comprises a negative expansion substrate, an optical fiber mounted on the substrate surface, and a grating defined in the optical fiber. The method for producing the athermal optical fiber reflective grating device comprises providing a negative expansion substrate, mounting an optical fiber with at least one reflective grating defined therein onto the substrate upper surface, and affixing the optical fiber to the substrate at at least two spaced apart locations.

Abstract: The invention is a method of making silicate based glass compositions with phosphorus compounds included in the composition as spectral modifiers to impart desirable color and improved energy absorbance properties. The phosphorus compound is generally a metal phosphide which is added to the batch glass composition in amounts greater than 0.05 weight percent prior to melting. The composition and method result in a finished glass suitable for use in architectural and automotive glazings.

Abstract: A non-phase separable glass material for fabricating a GRIN lens comprises 5-20 mole % boron oxide and ratio R of network modifiers in mole % to the network former boron oxide in mole % is in the range of about 1-1.5. The melted preform of such glass material is extruded through an opening to form a glass rod where the extrusion process eliminates bubbles that may be present in the preform. Neodymium oxide may be added in the frit material for forming the preform to reduce friction forces in the extrusion process and reduces the stress in the glass rod. Centerless grinding may be performed to control the diameter and roughness of the surface of the rod to control the diffusion parameters during the subsequent ion-exchange.

Abstract: The invention is a medium color gray soda-lime-silica glass composition having excellent ultra violet and infra red absorbing ability. The colorants of the glass composition consist essentially of: greater than 0.5 but less than 0.9 wt. % total iron oxide as Fe2O3; 0.1 to 1.0 wt. % manganese compound as MnO2; 0.0005 to 0.003 wt. % selenium as Se; 0.002 to 0.010 wt. % cobalt oxide as Co; up to 1.0 TiO2; the glass composition having, at 4.0 mm. thickness: 485-570 dominant wavelength, less than 5% purity of excitation, 35 to 60% light transmittance using Illuminant A, less than 40% ultra violet transmittance measured over 300-400 nm, and less than 45% infra red transmittance measured over 760-2120 nm.

Abstract: Polarizing glass having localized regions or patterns of non-polarizing glass is disclosed. The glass is formed by use of reducing gas-blocking material, by local thermal heating of the glass, or by an etching technique.

Abstract: A process for producing a polarizing glass containing shape-anisotropic metallic particles dispersed in an oriented state therein, which comprises drawing a glass preform containing metallic halide particles dispersed therein while its viscosity being held above 2×106, but below 7×107 poises; and subjecting the drawn glass to a reducing treatment so that a part or all of the metallic halide particles are reduced to metallic particles, which process enables it to produce a polarizing glass with a high yield from a starting material of a glass containing metallic halide particles, while avoiding glass breakage or fracture during elongation as well as preventing the elongated metallic halide particles from returning to a spherical shape.