Abstract: An object of the present invention is to provide a press-forming method for glass capable of uniformly heating press dies and a preform and preventing oxidation of the press dies. According to the press-forming method for glass of the present invention, a preform is placed between a pair of press dies in a press-forming chamber and the preform and the press dies are heated in an inert gas atmosphere. After the temperature of the press dies reaches a predetermined value, evacuation of the press-forming chamber is initiated. After the pressure of the press-forming chamber reaches a predetermined value and the temperature of the press-forming chamber are stabilized at a second predetermined value, the preform is press-formed. Preferably, an exhaust rate for evacuating the chamber is limited to a predetermined value or less.

Abstract: A glass sheet includes a first edge, an opposing, second edge, and an intermediate location between the first edge and second edge. The glass sheet has a first portion extending between the first edge and the intermediate location and a second portion extending between the intermediate portion and the second edge, wherein the first portion has a generally uniform thickness and the second portion has a varying thickness. The thickness of the second portion can either increase or decrease from the intermediate location to the second edge. A laminated transparency incorporating the glass sheet as well as a method of forming a glass ribbon having a changing thickness profile along at least a portion of the width of the ribbon are also disclosed.

Abstract: A transfer arm holds a plurality of preforms arranged in a single line and simultaneously drops and supplies the preforms downward. A positioning arm has a pair of arm split members split in its widthwise direction. The arm split members have positioning surfaces formed on their contact surfaces to be brought into contact with outer peripheries of the preforms. After the preforms are dropped and supplied from the transfer arm, the arm split members of the positioning arm are opened and closed so that the positioning surfaces are brought into contact with the outer peripheries of the preforms. Thus, the performs are properly positioned.

Abstract: A method of manufacturing glass parts for connection of glass fibers is provided, which can improve the accuracy of the cross-sectional size of a through hole in the glass part. A mother glass having a similar cross section to a desired cross section of a glass part having a through hole is prepared, and the prepared mother glass is drawn while it is heated. The mother glass is made of a glass having a maximum devitrification speed of 100 ?m or less per minute.

Abstract: In the present invention, a surface 7 of a glass substrate 1 is irradiated with a laser beam 2 to thereby form a V-shaped groove 6. At that time, the laser beam 2 is condensed outside and above the glass substrate 1. The distance between a beam-condensing point 4 of the laser beam 2 and the surface 7 of the glass substrate 1 is changed to thereby make it possible to change the angle between opposite side surfaces of the V-shaped groove. The angle is in a range of from 30 degrees to 120 degrees. Further, the laser beam used in the present invention is pulsed light, preferably with a pulse width not larger than 10 picoseconds.

Abstract: A press die and a molding process can form a disk member having a shaft shaped portion at a center with satisfactory circularity and flatness in a disk portion, dimensional precision in the shaft shaped portion, and concentricity between the disk portion and the shaft shaped portion at the center. The press die is designed for press molding of a glass substrate of a disk member with a shaft shaped portion at a center thereof. The press die includes an upper die forming an upper surface of the disk member, an intermediate die having a shaft forming hole portion for forming a shaft shaped portion projecting from a disk portion of the disk member, a lower die for forming a lower surface of the shaft shaped portion and a guide member for guiding the upper die, the intermediate die and the lower die.

Abstract: In the process for partially shaping, a glass/glass ceramic article (5) is held on a planar support plate (1) by suction. The glass/glass ceramic article is heated to soften it, so that it has a viscosity below 106 dPa·s. After the softening one or more shaping dies (4) is or are moved upward through an opening or respective openings (3) in the support plate to form raised regions in the softened glass/glass ceramic article (5). The suction force is produced by a low pressure in a hollow compartment (2) below the support plate (1) and acts on the glass/glass ceramic article (5) by means of a gap (G) formed between each shaping die (4) and the support plate. Additional openings can be provided in the support plate and/or in one or more of the shaping dies to assist in applying the suction force to the glass/glass ceramic article. After solidification of the softened glass/glass-ceramic article the shaping die or dies (4) is or are withdrawn.

Abstract: What is proposed here is a method of structuring surfaces of glass-type materials and variants of this method, comprising the following steps of operation: providing a semiconductor substrate, structuring, with the formation of recesses, of at least one surface of the semiconductor substrate, providing a substrate of glass-type material, joining the semiconductor substrate to the glass-type substrate, with a structured surface of the semiconductor substrate being joined to a surface of the glass-type substrate in an at least partly overlapping relationship, and heating the substrates so bonded by annealing in a way so as to induce an inflow of the glass-type material into the recesses of the structured surface of the semiconductor substrate. The variants of the method are particularly well suitable for the manufacture of micro-optical lenses and micro-mechanical components such as micro-relays or micro-valves.

Abstract: The forming apparatus has top and bottom die assemblies which form a heated silica glass material by press forming. These top and bottom die assemblies include, respectively, mold dies, which are made of isotropic carbon, and core molds, which are made of vitrified carbon. The heating and pressing time of a silica glass element, which requires a high forming temperature, is shortened by pinching the silica glass material between top and bottom core molds by controlling a torque so as to produce a close contact condition which permits heat transfer from the top and bottom core molds to the silica glass material between the top and bottom core molds.

Abstract: A press molding apparatus includes upper and lower mother molds 102 and 104. Each of the mother molds 102 and 104 has four molding surfaces arranged in a single line and satisfies the relationship given by L×?×?T/t<0.0008, where L represents the length, t, the thickness, ?, the thermal expansion coefficient, and ?T, the temperature difference between both ends in the thickness direction during induction heating. The press molding apparatus may include a pressing mold set including upper mother molds 102a and 102b attached to a common fixed shaft 118 through upper supporting shafts 110a and 110b and lower mother molds 104a and 104b driven by a common drive shaft 120 through lower supporting shafts 112a and 112b. The upper mother molds 102a and 102b and the lower mother molds 104a and 104b are collectively heated by induction heating coils 122 and 124, respectively.

Abstract: A method for making a polarizing glass article is provided. The method includes first providing a precursor glass containing metal-halide particles. The precursor glass may be encased in a gas-permeable medium. Then, form at least a first polarizing layer and a non-polarizing region in the precursor glass. Bond the polarizing layer to a substrate and removing the non-polarizing region to expose the polarizing layer. Then, separate the first polarizing layer from the substrate to produce an ultra-thin polarizing glass article measuring less than or equal to about 200 ?m in thickness. The method may further comprise cutting the polarizing layer into wafers.

Abstract: A jadeite material has a thickness in excess of about 1.0 mm and CIELAB indices of L*>42, a*<?6, and b*>+6. The grain size of the jadeite material is less than about 30 microns and is an equiaxed grain structure. The jadeite material has an optical transmission peak between 500 and 565 nm with an I/IO optical transmission ratio of over 40%. The first step in making the jadeite material is to wrap a glass block, convertible by HP/HT into jadeite and having a nominal composition of NaAlSi2O6, with a graphite or refractive metal sheet. The wrapped glass block is placed in an HP/HT apparatus, rapidly heated, and subjected therein to a pressure in excess of about 3 GPa and a temperature in excess of about 1000° C. for a time adequate to convert the glass block into jadeite. The jadeite material then is cooled and the pressure subsequently released.

Abstract: In a magnetic recording medium, surface roughness of a glass substrate and the variation of the surface roughness are suppressed to the predetermined range. Namely, the surface roughness (Rmax, Ra, Rq) and the relation (Rmax/Ra) between Rmax and Ra are restricted to the predetermined range. In this event, Ra is representative of a center-line mean roughness, Rmax is defined as a maximum height representative of a difference between a highest point and a lowest point and Rq is representative of a root mean square roughness. Thereby, crystal grains of an underlying layer and a magnetic layer formed thereon are equalized. Specifically, the surface roughness is specified by Rmax?15 nm, Ra?1 nm and Rq?1.5 nm. Further, the ratio between the surface roughness Rmax and the surface roughness Ra is specified by Rmax/Ra?30.

Abstract: The present invention relates to low-dispersion optical glass having a low glass-transition temperature suited to precision press molding, a press molding preform comprised of this glass, a method of manufacturing the same, an optical element, and a method of manufacturing the same. The optical glass comprises, given as molar percentages, 28 to 50 percent of P2O5; more than 20 percent but not more than 50 percent of BaO; 1 to 20 percent MgO; a sum of Li2O, Na2O, and K2O exceeding 3 percent (with 0 to 25 percent of Li2O, greater than or equal to 0 percent and less than 10 percent of Na2O, and 0 to 12 percent of K2O); more than 0 percent but not more than 15 percent of ZnO; 0 to 25 percent of B2O3; 0 to 5 percent of Al2O3; 0 to 8 percent of Gd2O3; 0 to 20 percent of CaO; 0 to 15 percent of SrO; and 0 to 1 percent of Sb2O3; with a sum of oxide contents of P, Ba, Mg, Li, Na, K, Zn, B, Al, Gd, Ca, Sr, and Sb being greater than or equal to 98 percent. The press molding preform is comprised of the optical glass.

Abstract: The present invention relates to a method of manufacturing an optical element by press molding in a pressing mold a heat-softened molding material such as a glass material to form a glass element, and then forming an optically functional film such as an antireflective film thereon. The method of manufacturing an optical element comprises: press molding a heat-softened molding material in a pressing mold to form an optical element of desired shape, and forming an antireflective film on the surface of the optical element obtained, wherein the antireflective film is formed on the optical element having a surface free energy of greater than or equal to 60 mJ/m2.

Abstract: Devices and techniques for placing and bonding identical elements to holes in a substrate where spacer balls and a reference surface are used to achieve the desired accuracy.

Abstract: An object of the present invention is to enable to use a common transfer machine for transferring performs to and for transferring products from a press-forming system for glass having a plurality of press units. The press-forming system for glass has a plurality of press units. A linear moving stage is arranged in the proximity of the press units. A transfer robot is mounted on the linear moving stage. A pallet changer is arranged in the proximity of an end of the linear moving stage. A tray presently in use is mounted on a first mount and a new tray on standby is mounted on a second mount on the pallet changer. The inner space of the tray is partitioned into sections so as to correspond to press units in number. In each section, a plurality of pockets is arranged for storing preforms or products one by one.

Abstract: A method for manufacturing a glass optical element having at least one concave surface, including: softening a glass molding material by heating, molding the softened material with a first mold having a first molding surface and a second mold having a second molding surface by applying a pressure, the first molding surface including a first concave forming surface, the second molding surface including a convex forming surface, a planar forming surface or a second concave forming surface, the second concave forming surface having a curvature radius greater than that of the first concave forming surface, whereby the applying of the pressure starts when the first mold and the second mold are at temperatures above a glass transition temperature of said glass molding material, the glass material is cooled so that a temperature of the glass material reaches a temperature equal to or lower than a glass transition temperature (Tg) of the glass material, and the cooled glass material is removed from either of the firs

Abstract: A process for fabricating a faceplate for a flat-panel display such as a field emission cathode type display is disclosed, the faceplate having integral spacer support structures. Also disclosed is a product made by the aforesaid process.

Abstract: Disclosed are processes for manufacturing glass optical elements by press molding a heated and softened glass material in preheated molds. In the process, the glass material is heated while it is floated by a gas blow and the heated and softened glass material is transferred to the preheated molds and then subjected to press molding. Alternatively, the process comprises: heating a glass material at a temperature at which the glass material has a viscosity of lower than 109 poises, preheating molds at a temperature at which the glass material has a viscosity of from 109 to 1012 poises, subjecting the heated and softened glass material to initial press in the preheated molds for 3 to 60 seconds, starting to cool the vicinity of molding surfaces of the molds at a rate of 20° C.

Abstract: A system and method for forming infrared glass optical components are provided. The system includes first and second mold halves having first and second respective faces. The first and second mold halves are configured to be removably coupled such that the first face and the second face form an interface that defines a lens-shaped cavity. A tapered surface of the first face cooperates with a tapered surface of the second face to enhance centering of the first face with respect to the second face.

Abstract: An optical substrate is provided with a surface of a desired shape by coating the surface with a thin layer of an optical glass and subsequently modifying the shape of the external surface of the layer. In preferred embodiments, the temperature of the substrate is maintained at substantially less than 400° C., the substrate is an optical component other than a simple window, and the refractive index o the optical glass is within 20% of the refractive index of the material providing the surface to be coated. One particular use is when both the substrate (e.g. a non-linear optical layer) and the optical glass are optically transmissive in the near infra-red and/or mid infra-red ranges. The glass layer can compensate for physical imperfections in the surface. It can be polished to optical quality, or provide with detail across the coated surface, e.g. as a “moth-eye” anti-reflection layer, or a diffractive or interference structure.

Abstract: A method of manufacturing a glass material for molding includes immersing a preformed glass material in an organic solution which contains an organic silicon-containing compound, an organic sulfur-containing compound, an organic fluorine-containing compound, or an organic nitrogen-containing compound to obtain the glass material which has a self-assembled film on a surface.

Abstract: Provided is a method for manufacturing a glass optical element comprising steps of: molding a glass material softened with a molding device which comprises an upper mold having a molding surface and a lower mold having a molding surface so that optically functional surfaces are formed on the glass material by applying a molding pressure, cooling the glass material so that the glass material obtains a predetermined viscosity, and removing the cooled glass material from the molding device, wherein a temperature of the glass material is maintained, in the cooling step, within a range of (Tg+30) to (Tg−50) degree centigrade at least for a predetermined time, and a secondary pressure is applied to the glass material at least during the predetermined time, so that the strain in the glass material is reduced, where Tg represents glass transition temperature of the glass.

Abstract: A molding die has a shell having a penetration hole, a lower pattern installed in the lower opening of the shell, and an upper pattern slidably disposed from the upper opening of the shell. The shell includes an outer shell and an inner shell disposed inside of the outer shell. The inner shell is includes plural split shells. The inner shell can be separated from the outer shell. The inner shell, lower pattern, and upper pattern form a cavity. As a result, if the molded product sticks to the inner circumference of the shell, the molded product can be easily taken out of the molding die by disassembling the shell. Further, a molded product having an excellent dimensional precision can be manufactured.

Abstract: A method and apparatus for making cylindrical glass preforms with convex, optical quality convex end surfaces is taught. A glass ball preform is placed on a heated lower platen. The temperature of the glass ball preform is raised to a temperature above the glass transition temperature of the glass ball preform. The glass ball preform is engaged with an upper platen. At least one of the upper platen and the lower platen is moved vertically to cause the gap between the upper platen and the lower platen to narrow to a predetermined dimension. Simultaneously, at least one of the upper platen and the lower platen is moved horizontally relative to the other platen to cause the glass ball preform to roll between the upper platen and the lower platen and form a cylindrical preform having a predetermined diameter, the cylindrical preform having convex, optical quality end surfaces.

Abstract: The invention relates to a method and a device for reducing the adhesion tendency during the hot forming of a glass body, using at least two moulds, which are positioned on either side of the glass body and are brought into contact with the glass body at a temperature, at which the glass is deformable, whereby the moulds are configured with electrically conductive surfaces. The disadvantage of existing methods and devices is that the moulds have a tendency to adhere to the glass body to be formed and that the surface quality of the glass is impaired. The invention therefore discloses a method, according to which the conductive surfaces of the moulds that come into contact with the glass body are supplied with an alternating current. The device for carrying out said method has electrically conductive mould surfaces, which are connected to an alternating current source. This guarantees that a larger processing window is available as a result of the reduced adhesion tendency, i.e.

Abstract: Methods for press molding a glass body, especially for optical applications, without additional grinding and polishing steps are described. One method is performed with a press mold having an upper mold part, a lower mold part and, if necessary or desired, a ring. In order to improve the quality of the products, especially glass bodies of larger diameters, a voltage is applied across the upper mold part and the lower mold part when the glass body is within the press mold and a pressing force is applied to the glass body when the temperature of the glass body matches the temperature of the press mold. Alternatively, in another method the press mold is cooled after it reaches a predetermined temperature and the pressing force is applied to the glass body in the mold after exceeding the sticking temperature (T0).

Abstract: Glass sheet, accurately curved in two directions and having a compound curved surface, provides a non-cylindrical, non-spherical, smooth, continuous reflection image. When it is used as a door window pane, a smooth opening/closing by a simple mechanism is ensured, and a high degree of freedom in a moving direction is provided. This shape, although unable to be accurately formed by a conventional press molding method, can be achieved by a glass sheet bending method using a heat-resisting belt.

Abstract: In one aspect, a method is provided for molding from glass complex optical components such as lenses, microlens, arrays of microlenses, and gratings or surface-relief diffusers having fine or hyperfine microstructures suitable for optical or electro-optical applications. In another aspect, mold masters or patterns, which define the profile of the optical components, made on metal alloys, particularly titanium or nickel alloys, or refractory compositions, with or without a non-reactive coating are provided. Given that molding optical components from oxide glasses has numerous drawbacks, it has been discovered in accordance with the invention that non-oxide glasses substantially eliminates these drawbacks. The non-oxide glasses, such as chalcogenide, chalcohalide, and halide glasses, may be used in the mold either in bulk, planar, or power forms. In the mold, the glass is heated to about 10-110° C., preferably about 50° C.

Abstract: An apparatus for bend-shaping a glass sheet is disclosed, which comprises a heating furnace, a plurality of in-furnace beds disposed within the heating furnace, at least one out-furnace bed disposed externally of the heating furnace proximately to an outlet of the heating furnace, and an elevating mechanism disposed below that one of the in-furnace beds which is positioned proximately to the outlet and the out-furnace bed. The in- and out-furnace beds have upper surfaces curved transversely and capable of jetting air to floatingly support a glass sheet. For producing a dual curved glass sheet, the elevating mechanism is operated to elevate opposed ends of the one in-furnace bed and the out-furnace bed so that these beds jointly form a hill. For producing a single-curved glass sheet, the elevating mechanism is operated to lower the opposed ends of those beds to their original flat positions.

Abstract: The present invention relates to a molding method of a microlens array with an enhanced transfer performance and a molding apparatus of the same. The invention addresses a method for molding a microlens array by heating and compressing a glass element between oppositely placed first and second cores, wherein a depression or projection part is formed for transferring and molding a plurality of concave lens elements on the compression molding surface of at least one of the cores. The glass element is set between each compression molding surface of the first and second cores, and is then compressed between them while providing restriction means for preventing the glass element from escaping in the direction perpendicular to the compression direction of the glass element, thereby compression molding the glass element with the restriction means and between the compression molding surfaces of the first and second cores.

Abstract: An method and apparatus for shaping a floor of a glass vessel including a source of pressurized gas, a pressure-sealed housing in fluid communication with the source of pressurized gas and a mold at least partially within the pressure-sealed housing. The mold includes a shaping floor with a first side subjected to the source of pressurized gas.

Abstract: A method for molding a chalcogenide glass lens includes providing a mold. A preformed lens of chalcogenide glass is placed within the mold. The lens has a top surface and a bottom surface. An amount of chalcogenide glass is deposited within the mold and on the top surface of the preformed lens. The mold is heated, such that the chalcogenide glass on the top surface of the preformed lens softens, melts, and bonds to the top surface of the preformed lens. A lens surface is formed in the melted chalcogenide glass to form a molded lens which is bonded to the top surface of the preformed lens. The molded lens and preformed lens assembly is then removed from the mold.

Abstract: A press apparatus includes a movable member having a mold-mounting surface for mounting a movable mold thereon and at least four guide surfaces; and a guide member having at least four guide surfaces facing the corresponding guide surfaces of the movable member. Fluid is injected into a space formed between the guide surfaces of the movable member and the corresponding guide surfaces of the guide member such that the mutually facing guide surfaces are held in a noncontacting condition.

Abstract: A high-refractivity high-dispersion optical glass for producing an optical element, which requires no machining, such as polishing or lapping, of an optical-function surface after precision press molding, containing B2O3, SiO2, La2O3, Gd2O3, ZnO, Li2O, ZrO2 and Ta2O5 as essential components, containing 0 to 1 mol % of Sb2O3 as an optional component, substantially containing none of PbO and Lu2O3, having a glass transition temperature of 630° C. or lower, and (1) having a refractive index nd and an Abbe's number &ngr;d which satisfy all of the following relational expressions, 1.80<nd≦1.90, 35<&ngr;d≦50, and nd≧2.025−(0.005×&ngr;d) or (2) having an nd of greater than 1.85 and a &ngr;d of greater than 35.

Abstract: A process for fabricating a face plate for a flat panel display such as a field emission cathode type display is disclosed, the face plate having integral spacer support structures. Also disclosed is a product made by the aforesaid process.

Abstract: A process for fabricating a face plate for a flat-panel display such as a field emission cathode type display is disclosed, the face plate having integral spacer support structures. Also disclosed is a product made by the aforesaid process.

Abstract: The present invention is directed to an apparatus for thermal treatment of glass and method and thermally treated glass therefrom. The apparatus is capable of supporting the glass during thermal treatment such as tempering, annealing, bending, and/or shaping which can include any cooling or quenching to remove heat or any combination of these. The apparatus is a support member like a ring or outline mold with a horizontal surface suitable for contacting the glass. The support member has at least a surface with or without a coating for contact with the glass of one or more metals having a thermal conductivity such that the glass heated for shaping cools at a rate not much slower than the cooling rate of unsupported sections of the glass. Suitable metals include those with a thermal conductivity of greater than around 16 BTU/(hour×feet×° F.).

Abstract: A method for forming an optical glass element by pressure molding a glass pre-form using top and bottom molds, has steps of heating a glass pre-form held at a position separated from the top and bottom molds by a holding member within the top and bottom molds, pressing the glass pre-form while the glass pre-form is held by the holding member, and moving the bottom mold independently in an upward direction and pressing the glass pre-form again.

Abstract: Disclosed are processes for manufacturing glass optical elements by press molding a heated and softened glass material in preheated molds. In the process, the glass material is heated while it is floated by a gas blow and the heated and softened glass material is transferred to the preheated molds and then subjected to press molding. Alternatively, the process comprises: heating a glass material at a temperature at which the glass material has a viscosity of lower than 109 poises, preheating molds at a temperature at which the glass material has a viscosity of from 109 to 1012 poises, subjecting the heated and softened glass material to initial press in the preheated molds for 3 to 60 seconds, starting to cool the vicinity of molding surfaces of the molds at a rate of 20° C.

Abstract: A method and apparatus are taught for molding glass lens elements from glass preforms. A glass preform is placed on a first mold surface of a first mold element which resides in a first sleeve segment. The temperature of the glass preform, the first mold element, the first sleeve segment, a second mold element, and a second sleeve segment are elevated to at least the glass transition temperature of the glass preform, the second mold element residing in the second sleeve segment. The second mold element and second sleeve segment are moved toward the first mold element and first sleeve segment to form a mold cavity, the mold cavity including a lens chamber and an annular channel projecting from the lens chamber. The glass preform is compressed in the mold cavity to form a glass lens element with the excess glass from the glass preform flowing into the annular channel.

Abstract: A device for cooling bent glass sheets running along a roller conveyor. Blowing boxes are inserted between the rollers and have a surface opposite the glass sheet at a distance of less than 30 mm and preferably less than 10 mm. The surface is perforated with several holes through which air is discharged in the direction of the glass sheets.

Abstract: A method of making a vehicle windshield or other window. An opaque layer (e.g., enamel or water-based) is applied to a glass sheet and then “fired” or cured. The opaque layer is preferably black or dark in color. Thereafter, the sheet with the opaque layer thereon is cut into a desired windshield shape, along a cutting line which extends through both the glass sheet and the opaque layer formed thereon. As a result, on the cut glass sheet the opaque layer extends all the way up to the peripheral edge thereof. In vehicle windshield embodiments, the cut sheet is laminated to another glass sheet via at least a polymer based interlayer in order to form the vehicle windshield.

Abstract: An optical component molding device and method is disclosed. The molding device includes a heating section, a heating/pressing section, and a cooling section. A carrying member sequentially conveys molding units between these treatment sections. Either the molding units or the carrying member is provided with coded information pertaining to the treatment each molding unit is to receive. A sensor scans the coded information and relays it to a master control unit that controls the operation of the various sections. The device automatically accommodates different height molds, as well as allows for different length pressing strokes, as well as different pressures, temperatures and rates of heating and cooling, and different durations of pressing to be individually controlled for each mold unit.

Abstract: A glass material (4) is placed in a forming die including a pair of upper and lower dies (1, 2) and a control member (3) for controlling the space between the upper and the lower die, and then heated, softened, and molded by pressure into a glass substrate in the shape of a parallel plate. The amount of thermal contraction of the control member is smaller than that of the glass material. Therefore, the glass substrate is released from the die when cooled after molding. The present invention can provide a glass substrate that is excellent in smoothness and form accuracy of the surface, and that is suitable for recording media such as magnetic disks that are inexpensive and suitable for mass production.

Abstract: Processes for manufacturing glass optical elements by press molding a heated and softened glass material in preheated molds. In the process, the glass material is heated while it is floated by a gas blow and the heated and softened glass material is transferred to the preheated molds and then subjected to press molding. Alternatively, the process comprises: heating a glass material at a temperature at which the glass material has a viscosity of lower than 109 poises, preheating molds at a temperature at which the glass material has a viscosity of from 109 to 1012 poises, subjecting the heated and softened glass material to initial press in the preheated molds for 3 to 60 seconds, starting to cool the vicinity of molding surfaces of the molds at a rate of 20° C.

Abstract: A process for fabricating a face plate for a flat panel display such as a field emission cathode type display is disclosed, the face plate having integral spacer support structures. Also disclosed is a product made by the aforesaid process.

Abstract: Disclosed is a mold including upper and lower molds for obtaining glass optical elements by press molding a glass molding material softened by heat, in which either one of the upper and lower molds is made of a ceramic matrix and the matrix has no surface hole having a diameter of 300 microns or more on the molding surface, and a method for manufacturing glass optical elements using the mold. For example, on the upper mold 21 and the lower mold 22, formed is a &bgr; type silicon carbide having a thickness that a molding surface can be reproduced by grinding and a density of 3.20 g/cm3 or more so as to include at least the molding surface facing a surface of the glass molding material G. The mold according to the invention can be reused even where pullouts occur from repetitive use.

Abstract: A silica-based core rod is traversed by a heat source along its longitudinal axis, to provide heated, softened regions. During the traverse, compressive or tensile movements are provided along the rod's longitudinal axis, these movements inducing, respectively, increases or decreases in the core diameter at the softened regions. By providing selective core diameter increases and/or decreases across the entire length of the core rod, a desired core diameter profile is attained. It is possible to attain a substantially uniform core diameter, or a varying core diameter profile that provides particular properties, such as systematically varying dispersion. In addition, due to the ability to increase core diameter and core rod diameter in a controlled manner, it is possible to make larger core rods, and in turn larger fiber preforms, than presently possible.