Tue, 05 Jan 2016 08:00:00 ESTMethods and apparatus for machining substrates are disclosed, as are articles formed from the separated substrates. A method of machining a substrate having a first surface and a second surface opposite the first surface can include forming a first recess in the substrate extending from the first surface toward the second surface, forming a second recess in the substrate extending from the second surface toward the first surface, and removing a portion of the substrate extending from the first recess to the second recess to form an opening in the substrate.
Tue, 26 May 2015 08:00:00 EDTThe present invention relates to a process for producing a base material for disks of disk rolls, in which the disk roll contains a rotating shaft and a plurality of the disks fitted on the rotating shaft by insertion whereby the outer peripheral surface of the disks serves as a conveying surface, in which the process contains molding a slurry raw material containing inorganic fibers, an inorganic filler having an aspect ratio of from 1 to 25 and an inorganic binder into a plate shape; and drying the molded plate.
Tue, 26 May 2015 08:00:00 EDTA porous preform production apparatus having a reaction vessel which includes an upper deposition chamber having an air supply inlet and an exhaust outlet, a lower deposition chamber having an air supply inlet, and a top chamber disposed on top of the upper deposition chamber and adapted to lift and store a porous preform formed by deposition, characterized in that the floor of the upper deposition chamber is disposed at a height between the lower end of a straight body part and the deposition tip of the porous glass preform during deposition, and a connection opening which connects the upper deposition chamber with the lower deposition chamber, is provided on the floor of the upper deposition chamber, and that when the aperture diameter of the connection opening is designated as A and the diameter of the porous preform passing through the connection opening as B, the ratio B/A satisfies the expression 0.05≦B/A≦0.6.
Tue, 26 May 2015 08:00:00 EDTAn apparatus and method for manufacturing glass objects comprising a blowing glass blowing pipe and a metal mounting insert configured to melt with glass to form a glass piece that is easily removed from the glass blowing pipe without the need to break the glass from the headstock of the glass blowing pipe. A method for manufacturing a glass object utilizing a metal mounting insert is described. A glass object having a metal mounting insert for installation and use in other applications is also described.
Tue, 26 May 2015 08:00:00 EDTA sag-bending glass sheet mold is disclosed. The sheet mold comprises a plurality of lateral support members, a plurality of longitudinal support members arranged perpendicular to the lateral support members, each of the plurality of lateral support members extending between two of the plurality of longitudinal support members, each of the plurality of longitudinal support members having an upper surface, and the upper surfaces of each of the plurality of longitudinal support members combined to form a mold support surface. The sheet mold can also comprise a glass-bearing support sheet disposed atop the mold support surface, the glass-bearing support sheet extending across the plurality of longitudinal support members and above the lateral support members, the glass-bearing support sheet having a curved upper surface.
Tue, 26 May 2015 08:00:00 EDTA dwell time control system and method for automatically adjusting the selection and timing of a sequence of pressures used to drive the plunger in a parison mold during the parison forming process. The timing of characteristics of the observed press curve from one or more previous parison forming cycles are ascertained and used to control the timing of the changes in pressure during a subsequent parison forming cycle. The timings of these changes of pressure are determined as predetermined percentages of the timings of the characteristics in order to prevent the blow mold from being forced open and in order to prevent the occurrence of an overpressed finish.
Tue, 26 May 2015 08:00:00 EDTA method of making a heat treated (HT) substantially transparent coated article to be used in shower door applications, window applications, tabletop applications, or any other suitable applications. Certain embodiments relate to a method of making a coated article including heat treating a glass substrate coated with at least layer of or including carbon (e.g., diamond-like carbon (DLC)) and an overlying protective film thereon. The protective film may be of or include both (a) an oxygen blocking or barrier layer, and (b) a release layer of or including zinc oxynitride (e.g., ZnOxNz). Following and/or during heat treatment (e.g., thermal tempering, or the like) the protective film may be entirely or partially removed.
Tue, 26 May 2015 08:00:00 EDTMethods and apparatuses for managing pulling forces applied to a glass ribbon in a draw apparatus are disclosed. The method includes applying a front-side and a rear-side drive torque to a glass. The method further includes calculating automatically with the at least one electronic controller a front-side and a rear-side average pulling force applied to the glass ribbon and corresponding to a first time period of at least one rotation of the front-side or rear-side stub roller, respectively. The front-side average pulling force and the rear-side average pulling force are compared to establish a pulling force differential between the front-side average pulling force and the rear-side average pulling force. One or more of the front-side drive torque or the rear-side drive torque are modified to decrease the pulling force differential between the front-side average pulling force and the rear-side average pulling force.
Tue, 26 May 2015 08:00:00 EDTWhen mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.
Tue, 26 May 2015 08:00:00 EDTA glass-substrate manufacturing method which includes a forming step and a cooling step. In the forming step, a molten glass is formed into a sheet glass by a down-draw process. In the cooling step, the sheet glass is cooled. The cooling step includes first, second and third coating steps as defined herein.
Tue, 26 May 2015 08:00:00 EDTA fusion down-draw method for making a glass sheet using a forming body comprising an upper part (101) made of a first material and a lower part (103) made of a second material, where the first material has lower creep rate than the second material at the normal operating temperature of the forming body, and an fusion down-draw forming apparatus comprising such forming body. The invention is advantageous in that it solves the issues of internal stress and long-term creep issue of a unitary forming body made of a single material such as zircon.
Tue, 26 May 2015 08:00:00 EDTMethods and apparatuses for steering flexible glass webs are disclosed. In one embodiment, a steering device for non-contact steering of a glass web having a conveyance direction and a cross direction normal to the conveyance direction includes a fluid injection bar having an elongate axis oriented in a cross direction of the glass web. The steering device also includes a pivot bearing assembly coupled to the fluid injection bar such that the fluid injection bar is pivotable in a plane perpendicular to the conveyance direction of the glass web, an actuator coupled to the fluid injection bar for adjusting the orientation of the fluid injection bar with respect to the glass web, and an edge detection device positioned proximate to an edge of the glass web for evaluating a position of an edge of the glass web.
Tue, 19 May 2015 08:00:00 EDTAn easily producible optical fiber preform which is drawn to an optical fiber having a core containing a sufficient concentration of alkali metal is provided. An optical fiber preform 10 is composed of silica-based glass and includes a core portion 20 and a cladding portion 30. The core portion 20 includes a first core portion 21 including a central axis and a second core portion 22 disposed on the perimeter of the first core portion 21. The cladding portion 30 includes a first cladding portion 31 disposed on the perimeter of the second core portion 22 and a second cladding portion 32 disposed on the perimeter of the first cladding portion 31. The core portion 20 contains an alkali metal at an average concentration of 5 atomic ppm or more. The concentration of the OH group in the perimeter portion of the first cladding portion 31 is 200 mol ppm or more.
Tue, 19 May 2015 08:00:00 EDTProvided are a spot size converter and a method of manufacturing the spot size converter. The method includes stacking a lower clad layer, a core layer, and a first upper clad layer on a substrate, tapering the first upper clad layer and the core layer in a first direction on a side of the substrate, forming a waveguide layer on the first upper clad layer and the lower clad layer, and etching the waveguide layer, the first upper clad layer, the core layer, and the lower clad layer such that the waveguide layer is wider than a tapered portion of the core layer on the side of the substrate and has the same width as that of the core layer on another side of the substrate.
Tue, 19 May 2015 08:00:00 EDTThe present invention relates to a method and system for monitoring and controlling a glass container forming process. The radiation emitted by each hot glass container is measured with measurement unit immediately after the forming machine. The described method normalizes the measurement from glass container to glass container and thereby removes the effects of overall temperature variations between glass containers, changing ambient conditions, and other variations affecting the measurements, which provides a unique quality reference for each glass container. By reviewing this reference for each produced glass container, the quality of the produced containers can be improved.
Tue, 19 May 2015 08:00:00 EDTA tempered glass substrate has a compression stress layer on a surface thereof, and has a glass composition comprising, in terms of mass %, 40 to 70% of SiO2, 12 to 21% of Al2O3, 0 to 3.5% of Li2O, 10 to 20% of Na2O, 0 to 15% of K2O, and 0 to 4.5% of TiO2, wherein the tempered glass substrate has a plate thickness of 1.5 mm or less, and an internal tensile stress in the tempered glass substrate is 15 to 150 MPa.
Tue, 19 May 2015 08:00:00 EDTProvided is a porous glass matrix producing burner 10, wherein a third gas jetting opening 17, which is the most outward one of a plurality of gas jetting openings, is clogged by a clogging member 19, and one line or plural lines of gas jetting holes 20 are provided in the clogging member 19 concentrically with respect to the center line of a glass material gas jetting port 11. Hence, there are provided a porous glass matrix producing burner that can have the cross-sectional area of its most outward gas jetting opening changed and can have the flow rate and linear velocity of a combustion improving gas adjusted to thereby suppress diffusion of the combustion improving gas and a combustible gas and improve deposition efficiency, and a porous glass matrix producing method using the porous glass matrix producing burner.
Tue, 19 May 2015 08:00:00 EDTProcesses and systems for producing glass fibers having regions devoid of glass using submerged combustion melters, including feeding a vitrifiable feed material into a feed inlet of a melting zone of a melter vessel, and heating the vitrifiable material with at least one burner directing combustion products of an oxidant and a first fuel into the melting zone under a level of the molten material in the zone. One or more of the burners is configured to impart heat and turbulence to the molten material, producing a turbulent molten material comprising a plurality of bubbles suspended in the molten material, the bubbles comprising at least some of the combustion products, and optionally other gas species introduced by the burners. The molten material and bubbles are drawn through a bushing fluidly connected to a forehearth to produce a glass fiber comprising a plurality of interior regions substantially devoid of glass.
Tue, 19 May 2015 08:00:00 EDTA fluid applicator (20), for cleaning particles from a glass sheet (2), including a conveyor (40) for supporting the glass sheet, a conveyance plane, and a nozzle (24). The conveyance plane is disposed adjacent the conveyor so that when the glass sheet is conveyed by the conveyor, a surface (6) of the glass sheet is disposed in the conveyance plane. The nozzle has a longitudinal axis (23), wherein the longitudinal axis is disposed at an angle of 30 to 90 degrees with respect to the conveyance plane, and the nozzle is disposed at a distance (21) of less than or equal to 100 mm from the conveyance plane. Also, there is disclosed a method for cleaning particles from a glass sheet, using the fluid applicator. The fluid may be delivered to the nozzle at a pressure of 10 to 80 kg/cm2 and a flow rate of from 1 to 20 l/min.
Tue, 12 May 2015 08:00:00 EDTA substrate for p-Si TFT flat panel displays made of a glass having a high low-temperature-viscosity characteristic temperature and manufactured while avoiding erosion/wear of a melting tank during melting through direct electrical heating. The glass substrate comprises 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-20 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-0.8 mass % of R2O, wherein R2O is total amount of Li2O, Na2O, and K2O, and 0-0.3 mass % of Sb2O3, and substantially does not comprise As2O3, wherein the mass ratio CaO/RO is equal to or greater than 0.65, the mass ratio (SiO2+Al2O3)/B2O3 is in a range of 7-30, and the mass ratio (SiO2+Al2O3)/RO is equal to or greater than 5. A related method involves melting glass raw materials blended to provide the glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.
Tue, 12 May 2015 08:00:00 EDTApparatus and equipment for making glass sheet from a glass ribbon including scoring, bending and separation in vertical state with improved glass ribbon stability provided by edge restrainers located above the score-line that also travel with substantially the same vertical velocity with the elastic ribbon. The edge restrainers on both sides of the glass ribbon serve to limit the motion and perturbation of the ribbon during scoring, bending and separation, advantageously by tensioning the glass ribbon where needed. The invention can reduce disturbance of the glass ribbon in upstream visco-elastic and/or viscous zones due to scoring, bending and separation, therefore enhance forming process stability and product attributes such as thickness variation, stress and stress variation, and the like. The invention can be particularly advantageous for making glass sheet with large width and/or low thickness using the fusion down-draw, slot down-draw, re-draw down-draw, and other down-draw processes.
Tue, 12 May 2015 08:00:00 EDTA method of forming fused quartz glass is provided. The method includes the steps of: (a) providing a starting body made of fused quartz glass; (b) positioning the fused quartz glass starting body on a base plate; (c) inserting a first insert device into an interior cavity of the starting body to form an assembled structure; (d) heating the assembled structure to a predetermined temperature at which the fused quartz glass has a viscosity in a range of 105 to 1013 poise; and (e) deforming the fused quartz glass of the starting body at the predetermined temperature or in the viscosity range of 105 to 1013 poise around the first insert device to change a shape of the starting body. A method for making a large fused quartz glass vessel and a forming assembly for forming fused quartz glass are also provided.
Tue, 12 May 2015 08:00:00 EDTA method includes forming a glass ribbon by heating and softening a glass plate preform and drawing the glass plate preform to a predetermined thickness in a heating furnace; and performing coring on the glass ribbon in order to form circular substrates in a straight line along a longitudinal direction of the glass ribbon.
Tue, 05 May 2015 08:00:00 EDTTo provide a method for producing a magnetic disk, whereby a magnetic recording layer is formed at a high temperature. A method for producing a magnetic disk, which comprises a step of forming a magnetic recording layer on a glass substrate having a temperature of at least 550° C., wherein the glass substrate comprises, as represented by mol percentage, from 62 to 74% of SiO2, from 6 to 18% of Al2O3, from 2 to 15% of B2O3 and from 8 to 21%, in total, of at least one component selected from MgO, CaO, SrO and BaO, provided that the total content of the above seven components is at least 95%, and further contains less than 1%, in total, of at least one component selected from Li2O, Na2O and K2O, or contains none of these three components.
Tue, 05 May 2015 08:00:00 EDTA non-contact support platform system is provided for supporting a substantially flat object. The system includes a platform with a first plurality of pressure ports and a first plurality of vacuum ports for inducing a fluid cushion to support the object at a distance from the platform. The system further includes a second plurality of pressure ports located at a predetermined zone of the platform for increasing the distance of the object from the platform at the predetermined zone.
Tue, 05 May 2015 08:00:00 EDTA fiber optic connector fiber stub remover and method for automated fiber stub removal. The device has a top plate with a platen opening, and a platen with a well that carries a polishing film over the well. An air pocket is formed between the polishing film and the well. The platen is positioned with a top surface of the polishing film accessible via the platen opening. A fixture holds connector ends of fiber optic cables with fiber stubs extending therefrom, and a weight biases the fiber stubs into contact with the polishing film. A motor is controlled by a motor control unit to control a ramp up time and final speed of movement of the platen over a timespan. Each connector ends moves independently relative to the polishing film. The air pocket provides shock absorption of the polishing film so that an ideal pressure is exerted on each fiber stub during stub removal.
Tue, 05 May 2015 08:00:00 EDTSubmerged combustion systems and methods of use to produce glass. One system includes a submerged combustion melter having a roof, a floor, a wall structure connecting the roof and floor, and an outlet, the melter producing an initial foamy molten glass. One or more non-submerged auxiliary burners are positioned in the roof and/or wall structure and configured to deliver combustion products to impact at least a portion of the bubbles with sufficient force and/or heat to burst at least some of the bubbles and form a reduced foam molten glass.
Tue, 05 May 2015 08:00:00 EDTA method of cleaving and separating a glass sheet includes a cleaving step of cleaving a glass sheet along preset cleaving lines by a laser cleaving method, and a separation step of separating adjacent pieces of the cleaved glass sheet from each other. The cleaving step is performed under a state in which the glass sheet is placed on support members provided respectively in segment regions, which are segmented by the preset cleaving lines. The separation step is performed by separating the support members from each other in adjacent segment regions.
Tue, 05 May 2015 08:00:00 EDTWhen melting a glass layer 3 by irradiation with laser light L1 along a region to be fused R, the glass layer 3 is irradiated with the laser light L1 having a first heat input along the region to be fused R, so as to gasify a binder and melt a glass frit 2, and the heat input is switched when the melting ratio of the glass layer 3 in a direction intersecting an advancing direction of the laser light L1 exceeds a predetermined value, so as to irradiate the glass layer 3 with the laser light L1 having a second heat input smaller than the first heat input along the region to be fused R, thereby gasifying the binder and melting the glass fit 2, thus fixing the glass layer 3 to a glass member 4.
Tue, 28 Apr 2015 08:00:00 EDTA float glass furnace includes a melting furnace which heats raw materials to form a molten glass batch, a working end where the molten glass batch is cooled, at least one regenerator which introduces heated combustion air into the melting furnace through a port neck, and at least one oxygen lance in or proximate the port neck. The oxygen lance includes a lance pipe in fluid communication with the port neck, an outer shell surrounding the lance pipe, an inlet water passageway in fluid communication with a channel(s) between an exterior surface of the lance pipe and an interior surface of the outer shell, and an outlet water passageway in fluid communication with the channel(s).
Tue, 28 Apr 2015 08:00:00 EDTIn one embodiment, a pulling roll for drawing glass sheet in a down-draw process includes a shaft member and a compliant cover assembly positioned on the shaft member. The compliant cover assembly includes at least one traction disk positioned on the shaft member. The at least one traction disk includes an annular hub and a plurality of spring elements integrally formed with the annular hub. The spring elements project outward from the annular hub such that an end of each spring element is positioned radially outward from a base of each spring element and is circumferentially offset relative to the base of each spring element.
Tue, 28 Apr 2015 08:00:00 EDTA glass for a magnetic recording medium substrate permitting the realization of a magnetic recording medium substrate affording good chemical durability and having an extremely flat surface, a magnetic recording medium substrate comprised of this glass, a magnetic recording medium equipped with this substrate, and methods of manufacturing the same. The glass is an oxide glass not including As or F.
Tue, 28 Apr 2015 08:00:00 EDTA glass layer 3 is irradiated with laser light L2 for temporary firing in order to gasify a binder and melt the glass layer 3, thereby fixing the glass layer 3 to a glass member 4. Here, an irradiation region of the laser light L2 has regions A1, A2 arranged along an extending direction of a region to be fused R and is moved along the region to be fused R such that the region A1 precedes the region A2. The region A2 irradiates the glass layer 3 before the glass layer 3 molten by irradiation with the region A1 solidifies. This makes the glass layer 3 take a longer time to solidify, whereby the binder gasified by irradiation with the region A1 of the laser light L2 is more likely to escape from the glass layer 3.
Tue, 28 Apr 2015 08:00:00 EDTA method for manufacturing a plurality of glass microspheres comprises: melting a batch into a first glass melt in a melter system, processing the first glass melt into a second glass, pulverizing the second glass into a plurality of glass fragments, thermally processing the plurality of glass fragments into a plurality of glass microspheres, providing at least one of a plurality of redox reactions and a plurality of events in at least one of the first glass melt and a melt of the second glass, and the plurality of redox reactions and the plurality of events are induced by a plurality of redox active group (RAG) components.
Tue, 21 Apr 2015 08:00:00 EDTThe invention relates to a melt composition for the production of man-made vitreous fibers and man-made vitreous fibers comprising the following oxides, by weight of composition: SiO239-43 weight %Al2O320-23 weight %TiO2up to 1.5 weight %Fe2O35-9 weight %, preferably 5-8 weight %CaO8-18 weight %MgO5-7 weight %Na2Oup to 10 weight %, preferably 2-7 weight %K2Oup to 10 weight %, preferably 3-7 weight %P2O5up to 2%MnOup to 2%R2Oup to 10 weight % wherein the proportion of Fe(2+) is greater than 80% based on total Fe and is preferably at least 90%, more preferably at least 95% and most preferably at least 97% based on total Fe.
Tue, 21 Apr 2015 08:00:00 EDTA laser annealing apparatus includes a lens unit configured to transmit a laser beam to be irradiated onto an irradiation target; a lens unit housing accommodating the lens unit and having an opening configured to allow the laser beam to pass through the opening; a blocking plate configured to block at least a portion of the laser beam reflected by the irradiation target after being transmitted through the lens unit to the irradiation target; and a cooling unit between the blocking plate and the lens unit housing.
Tue, 21 Apr 2015 08:00:00 EDTProvided is a method of cleaving and separating a glass sheet (G), the method comprising: a cleaving step of cleaving the glass sheet (G) along preset cleaving lines (X, Y) by a laser cleaving method; and a separation step of separating adjacent pieces of the cleaved glass sheet (G) from each other, wherein the cleaving step is performed under a state in which the glass sheet (G) is placed on a sheet (S) having stretchability, and the separation step is performed by stretching the sheet (S).
Tue, 21 Apr 2015 08:00:00 EDTIn a method of making shaped glass articles, a glass sheet is placed on a mold having a shaping surface with a desired surface profile of a shaped glass article. The glass sheet is preferentially and rapidly heated by radiation while in the vicinity of the mold so that the mold remains substantially cooler than the glass sheet during the heating. The glass sheet is sagged onto the shaping surface of the mold so that at least a portion of the sagged sheet assumes the desired surface profile of the shaped glass article. After sagging and shaping, the sagged and shaped glass sheet is removed from the mold.
Tue, 21 Apr 2015 08:00:00 EDTIon transport membranes are integrated with a glass melting furnace and a float glass bath. Only feeds of air, steam and hydrocarbon are necessary for producing hot oxygen for the melting furnace and a mixture of nitrogen, carbon dioxide, and hydrogen for the float glass bath.
Tue, 21 Apr 2015 08:00:00 EDTA glass sheet cutting device fuses and divides a glass substrate using a preset cutting line as a boundary while supplying an assist gas and a laser beam from above the glass substrate along the preset cutting line of the glass substrate. The glass sheet cutting device includes a first laser irradiator for radiating a fusing laser beam and a second laser irradiator for radiating an annealing laser beam. Through a fusing gap formed between fused end surfaces by fusing, the second laser irradiator radiates the annealing laser beam obliquely from above onto the fused end surface to be annealed.
Tue, 21 Apr 2015 08:00:00 EDTA method for producing a vial with low alkali elution by removing a deteriorated region caused by processing on an internal surface of a vial is disclosed. The method is for forming vials from borosilicate glass tubes with a bottom wherein an internal surface of the tube is fire-blasted with a flame.
Tue, 21 Apr 2015 08:00:00 EDTDisclosed are a vacuum glass panel and a manufacturing method of the same. The vacuum glass panel according to the present invention includes a first glass plate, a second glass plate facing the first glass plate with a vacuum space therebetween, an edge of the second glass plate being in contact with the first glass plate, and a plurality of spacers disposed between the first glass plate and the second glass plates to separate the first glass plate and the second glass plate from each other. The plurality of spacers are formed of a glass including alumina (Al2O3) particles and silica (SiO2) particles.
Tue, 21 Apr 2015 08:00:00 EDTA method of reducing distortion in a glass sheet is described and comprises the steps of: forming a glass ribbon in a glass manufacturing process; separating a glass sheet from the glass ribbon, the glass sheet having a substantially flat surface; measuring a retardation through the surface of the glass sheet; defining a retardation parameter indicative of the retardation of the glass sheet; cutting the glass sheet into a plurality of sub-sheets; measuring a distortion of the sub-sheets; defining a distortion parameter indicative of the distortion of the sub-sheets; and determining a correlation between the retardation parameter and the distortion parameter such that the distortion parameter of sub-sheets of a subsequent glass sheet can be predicted based on the correlation.
Tue, 14 Apr 2015 08:00:00 EDTDisclosed is a linear conveyor (21) for transporting glass panels (3) in the vicinity of grinding stations (9, 13) or a washing station (15) of a system for producing glass panel blanks including a linear conveyor (23), for example, a driven toothed belt, and opposite the driven toothed belt a beam (25), from which a fluid, in particular water, is discharged. The glass panel (3) is pressed against the linear conveyor (23) in a non-positive manner and reliably conveyed by water discharged from the beam (25). Such linear conveyors (21) can be arranged at the upper or lower edge of a glass panel (3) in order to trim the glass panel using at least one grinding disk (27), for example.
Tue, 14 Apr 2015 08:00:00 EDTA process and apparatus for precision glass roll forming a supply of molten glass at a glass temperature of 1000° C. or higher with a pair of hot forming rolls having a surface temperature of about 500° C. or higher located vertically below the glass feed. The forming rolls thin the supplied stream of molten glass to produce a formed glass ribbon. A pair of cold sizing and texturing rolls maintained at a surface temperature of about 400° C. or lower or 300° C. or lower is located vertically below the forming rolls. The sizing and texturing rolls thin and texture the formed glass ribbon to produce a sized glass ribbon having a desired texture, thickness and thickness uniformity. The sized and textured glass ribbon may have a thickness of 1 mm or less that varies in thickness by no more than +/−0.025 mm.
Tue, 14 Apr 2015 08:00:00 EDTThe present invention provides a glass substrate for magnetic disk in which surface irregularity of a principal surface is suppressed and a method for efficiently manufacturing a glass substrate for magnetic disk. The method includes the steps of: forming a sheet glass material by performing press forming to molten glass, a principal surface of the sheet glass material having target flatness for the glass substrate for magnetic disk, the sheet glass material having a surface shape to be ground using a grinding abrasive grain; grinding the sheet glass material using a fixed abrasive grain; and polishing the sheet glass material using a loose abrasive grain, the sheet glass material having surface irregularity of the principal surface ground using the fixed abrasive grain.
Tue, 14 Apr 2015 08:00:00 EDTThis invention provides a porous glass with a varied porous structure that shows an excellent optical performance. A method of manufacturing a porous glass comprising: a first step of forming a surface layer containing a boron compound and an alkali metal compound as main ingredients on a matrix glass containing a silicon oxide, a boron oxide and an alkali metal oxide; a second step of heat treatment the matrix glass and the surface layer for phase separation to form a phase-separated glass; and a third step of acid treatment the phase-separated glass to form the porous glass having pores.
Tue, 14 Apr 2015 08:00:00 EDTA silica crucible is made in a mold cavity of the type in which ambient atmosphere can be drawn through silica grain in the cavity. In one embodiment, a silica grain layer is formed in the mold cavity and gas, which may comprise helium, nitrogen, hydrogen, or a mixture thereof, is introduced into the mold cavity. The silica grain layer is heated while substantially no ambient atmosphere is drawn through the silica grain. Thereafter, at least a portion of the silica grain layer is fused while drawing ambient atmosphere through the silica grain. The gas displaces air in the mold cavity thereby reducing nitrogen oxides and ozone.
Tue, 07 Apr 2015 08:00:00 EDTA downsized, low-power electro-optical modulator that achieves reducing both of the additional resistance in the modulation portion and the optical loss each caused by electrodes at the same time is provided. The electro-optical modulator includes a rib waveguide formed by stacking a second semiconductor layer 9 having a different conductivity type from a first semiconductor layer 8 on the first semiconductor layer 8 via a dielectric film 11, and the semiconductor layers 8 and 9 are connectable to an external terminal via highly-doped portions 4 and 10, respectively. In a region in the vicinity of contact surfaces of the semiconductor layers 8 and 9 with the dielectric film 11, a free carrier is accumulated, removed, or inverted by an electrical signal from the external terminal, and whereby a concentration of the free carrier in an electric field region of an optical signal is modulated, so that a phase of the optical signal can be modulated. At least one of the semiconductor layers 8 and 9 is wider than the stacked portion. At least one of the highly-doped portions 4 and 10 is formed outside the stacked portion.
Tue, 07 Apr 2015 08:00:00 EDTA known method for producing synthetic quartz glass comprises the method steps of: forming a stream of a SiO2 feedstock material which contains octamethylcyclotetrasiloxane (D4) as the main component which has a reference molecular mass assigned to it, feeding the stream to a reaction zone in which the feedstock material is converted under formation of amorphous SiO2 particles by pyrolysis or hydrolysis into SiO2, depositing the amorphous SiO2 particles on a deposition surface while forming a porous SiO2 soot body, and vitrifying the SiO2 soot body while forming the synthetic quartz glass. Starting therefrom, to enable the production of large-volume cylindrical soot bodies with outer diameters of more than 300 mm of improved material homogeneity, it is suggested according to the invention that the feedstock material contains additional components in the form of further polyalkylsiloxanes, wherein light polyalkylsiloxanes with a relative molecular mass of less than the reference molecular mass are contained with a weight fraction of at least 50 ppm, and heavy polyalkylsiloxanes with a relative molecular mass of more than the reference molecular mass are contained with a weight fraction of at least 30 ppm.