Abstract: A method of forming an optical fiber preform includes: flowing a silicon halide and an oxidizer inside of a substrate tube, wherein a molar ratio of the silicon halide to the oxidizer is from about 1.5 to about 5.0; applying a plasma to the substrate tube to heat the substrate tube to a temperature of from about 1000° C. to about 1700° C.; and depositing silica glass comprising a halogen inside the substrate tube.

Abstract: A mold includes a lower mold core and an upper mold core. The lower mold core has a first outside surface and a first molding surface including a first molding portion and a first supporting portion surrounding the molding portion. The upper mold core has a second molding surface opposite to the first molding surface and encloses a molding cavity with the first molding surface. The lower mold core includes a first gas inlet on the first outside surface, a first gas outlet on the first supporting portion, and a first gas channel in the lower mold core, the first gas channel connecting the first gas inlet and the first gas outlet. Gas flow out from the first gas outlet to separate the glass product from the lower mold core before the glass product is completely cooled down, which can avoid many adverse effects during the glass product process.

Abstract: A system and method for processing an optical fiber includes a treatment device disposed downstream of a furnace and including a treating zone. The treating zone includes a fiber inlet and fiber outlet and is configured to cool the optical fiber at a reduced pressure below ambient pressure and at a slow cooling rate less than an ambient cooling rate. A nozzle assembly is disposed at one or more of the fiber inlet, the fiber outlet, upstream of the treating zone, and downstream of the treating zone. The nozzle assembly includes multiple baffle plates defining a number of nozzle chambers, each nozzle chamber having a nozzle chamber pressure, wherein each baffle plate includes an orifice having a predetermined effective orifice diameter through which the optical fiber passes. Each nozzle chamber is configured to sequentially change a nozzle chamber pressure between the reduced pressure and ambient pressure.

Abstract: A bushing for producing glass fibers, including: a base plate; and multiple nozzles from which molten glass is discharged, in which a nozzle group formed with the alignment of the multiple nozzles is joined to the base plate. A coating layer made of ceramics is formed on each of the nozzles forming at least a row of the outermost layer of the nozzle group, but the coating layer does not cover the entire nozzle, that is, the nozzle is covered so as to be in a state of no coating layer in the vicinity of the nozzle tip.

Abstract: A method for elongating a glass preform for an optical fiber is provided for producing a glass rod having a smaller diameter by elongating the glass preform having a large diameter, the method including: when the glass preform having a tapered transparent glass portion at one end of a straight body of the glass preform and a tapered portion including an opaque glass portion at another end is elongated, prior to the elongating, cutting a part of the tapered portion including the opaque glass portion, wherein a cut surface of the part is a lower end of the glass preform; and welding the cut surface of the tapered portion to a pulling dummy connected to a pulling mechanism in a elongating apparatus, wherein the cut surface is circular and has an outer diameter ranging from 135 mm to 160 mm.

Abstract: A device for manufacturing curved glass, includes a bending station that has a solid concave bending upper mold and a complementary lower countermold, the upper mold being placed above the lower countermold, a conveyor to convey the glass to a final holder placed under the bending upper mold, the final holder being circumscribed, seen from above, by the lower countermold, the final holder forming a surface for receiving the glass, the glass being in an optimal bending position when on this surface, the lower countermold being of the frame type and being able to move vertically in order to pass below or above the surface for receiving the glass, the bending upper mold and the lower countermold being able to move with a relative vertical movement that allows them to be brought together, in order to clamp therebetween the periphery of the glass, and to move apart from each other.

Abstract: The vacuum-based methods of forming an optical fiber preform include applying a vacuum to a preform assembly. The preform assembly has at least one glass cladding section with one or more axial through holes, with one or more canes respectively residing in the one or more axial through holes. The opposite ends of the at least one glass cladding section are capped to define a substantially sealed internal chamber. A vacuum is applied to the substantially sealed internal chamber to define a vacuum-held preform assembly. The methods also include heating the vacuum-held preform assembly to just above the glass softening point to consolidate the vacuum-held preform to form the cane-based glass preform. An optical fiber is formed by drawing the cane-based glass preform. The same furnace used to consolidate the vacuum-held preform can be used to draw the optical fiber.

Abstract: Provided is a method of molding an optical element to obtain the molded optical element. The method includes: preparing a die set including an upper die having an upper molding surface, a lower die having a lower molding surface, a side die in which a through hole is formed, and a sleeve configured to accommodate the upper die, the lower die, and the side die; disposing a mold material on the lower molding surface after inserting the lower die into the through hole of the side die; heating the mold material; press molding the mold material with the upper die and the lower die to integrally move the side die and the lower die with respect to the upper die and the sleeve; and pushing the optical element upward by raising the lower die with respect to the side die and the sleeve.

Abstract: A feed assembly for a melting chamber having a plurality of walls and at least one submerged burner, and related methods of its operation are disclosed. The feed assembly includes a tubular body being hollow and having a first end and extending to a second end. The second end is for connecting to one of the plurality of walls. The tubular body further includes a port proximate the second end wherein the port has a first port end and tapers radially inwardly to a second port end at the second end. The feed assembly also has a batch charger disposed within the tubular body and having a first charger end and extending to a second charger end.

Abstract: The efficiency of ion exchange processes is increased by increasing the concentration of nitrite salts in the molten salt bath. The increase in nitrite salt concentration may be achieved by adding a nitrite salt to a molten nitrate salt bath, aging a molten nitrate salt bath, or a combination thereof. The glass-based articles produced using the modified baths exhibit reduced haze and increased flexural strength.

Abstract: A method of reworking lithium containing ion exchanged glass-based articles is provided. The method includes a reverse ion exchange process that returns the glass-based article to approximately the composition of the glass from which the glass-based article was produced, before being subjected to ion exchange.

Abstract: The invention relates to exemplary methods, devices, and systems for heating an elongate silica cylinder to form a core-rod for optical fibers. An exemplary heating device includes an elongate cavity, an elongate liner bounding the cavity, a heating element in a heating element space surrounding the liner, the liner separating the heating element space from the cavity, and a gas flushing device for effecting a flow of gas at least through the heating element space. An exemplary method includes providing the elongate silica cylinder such that it extends through the cavity, heating the cylinder locally beyond its softening temperature, and effecting a flow of argon and nitrogen gas during the heating.

Abstract: One aspect relates to a process for the preparation of a quartz glass body. The process includes providing a silicon dioxide granulate I prepared from a pyrogenically produced silicon dioxide powder, treating the silicon dioxide granulate I with a reactant at a temperature in a range from 1000 to 1300° C., and making a glass melt out of the silicon dioxide granulate. A quartz glass body is made out of at least a part of the glass melt. Furthermore, one aspect relates to a quartz glass body obtainable by this process. Furthermore, one aspect relates to a light guide, an illuminant, and a formed body, each of which is obtainable by further processing of the quartz glass body. One aspect additionally relates to a process for the preparation of a silicon dioxide granulate II.

Abstract: A glass fining system, glass fining device, and method are disclosed. The glass fining device in accordance with one aspect of the disclosure includes at least one heated orifice through which molten glass flows from a glass melter to produce at least one superheated glass stream; and a low-pressure chamber disposed downstream from the heated orifice, where the at least one superheated glass stream flows from the at least one heated orifice and into the low-pressure chamber, and where the low-pressure chamber surrounds the at least one superheated glass stream. In some embodiments, the low-pressure chamber may include at least one surface extender.

Abstract: A method of fabricating a variable diameter fiber includes providing a fiber optic cable comprising a cladding region, a fiber core, and a plurality of sacrificial regions disposed in the cladding region and focusing a laser beam at a series of predetermined locations inside the fiber optic cable. The method also includes creating a series of damage sites associated with the series of predetermined locations, wherein the series of damage sites define a variable diameter profile and a latticework in the cladding region of the fiber optic cable. The method further includes exposing the fiber optic cable to an etchant solution, preferentially etching the series of damage sites, and separating peripheral portions of the fiber optic cable to release the variable diameter fiber.

Abstract: A melting apparatus is disclosed, the melting apparatus including a melting vessel with a back wall, a front wall, a first side wall, a second side wall and a longitudinal centerline extending therebetween and a width between the first and second side walls orthogonal to the centerline. The melting vessel further includes a first feed screw including a first axis of rotation and a second feed screw including a second axis of rotation, the first axis of rotation positioned between the longitudinal centerline and the first side wall and the second axis of rotation positioned between the longitudinal centerline and the second side wall. The positions of either one or both the first and second axes of rotation are located from a respective side wall a distance that is equal to or less than about 15% of the width of the melting vessel.

Abstract: An optical fiber drawing method where a glass base material passes through an opening provided in a drawing furnace from the material side and drawing is performed by suspending and descending the material into the drawing furnace while being sealed by a sealing mechanism provided in the vicinity of the opening, in which a first portion of the sealing mechanism seals a gap between an outer peripheral surface of the material and an inner surface of the opening when drawing starts and a tapered portion of the material starts passing through the first portion, and a second portion is disposed above the first portion before sealing by the first portion becomes ineffective, and then conduction between inside and outside of the drawing furnace is carried out to prevent fluctuation of pressure inside the furnace immediately after disposing the second portion and the conduction is interrupted when the material further descends.

Abstract: Exemplary embodiments of the present disclosure provide a method and apparatus for forming an ophthalmic lens. An exemplary method includes providing a plurality of posterior tools each having a posterior optic defining surface and a plurality of anterior tools each having an anterior optic defining surface, wherein each one of the plurality of posterior tools has a different central posterior optic defining surface including a unique conic section. The method further includes selecting one of the plurality of posterior tools and one of the plurality of anterior tools based on a criteria, and forming a posterior mold by the selected one of the plurality of posterior tools and an anterior mold by the selected one of the plurality of anterior tools, the posterior mold and the anterior mold operable to form an ophthalmic lens having the criteria.

Abstract: A method of molding a window for a display device includes: forming curved side surfaces and curved corners of the window, by pressing a heated preliminary window glass to a mold. The mold includes: a flat portion corresponding to a flat display portion of the display device; a window side surface bending portion corresponding to the side surfaces of the display device; and a window corner bending portion corresponding to the corners of the display device. The forming the curved side surfaces of the window includes pressing the heated preliminary window glass against the window side surface bending portion of the mold; and after the forming of the curved side surfaces, forming the curved corners and a flat portion of the window by further pressing the heated preliminary window glass respectively against the window corner bending portion and the flat portion of the mold.

Abstract: Methods for reducing a defective area in a strengthened substrate to produce a non-defective substrate are provided. The methods include contacting a strengthened defective substrate with a heated salt bath containing at least one monovalent salt, and removing the strengthened substrate from the bath. The strengthened substrate, before being contacted with the salt bath, is a defective substrate having at least one defective area and one or more non-defective area. Upon removal from the salt bath, at least one defective area has been reduced or substantially removed to produce a non-defective substrate.