Abstract: A method of forming a strengthened glass article is provided. The method includes providing a strengthened glass article. The strengthened glass article is in the form of a container including a sidewall having an exterior surface and an interior surface that encloses an interior volume. The sidewall has an exterior strengthened surface layer that includes the exterior surface, an interior strengthened surface layer that includes the interior surface and a central layer between the exterior strengthened surface layer and the interior strengthened surface layer that is under a tensile stress. A laser-induced intended line of separation is formed in the central layer at a predetermined depth between the exterior strengthened surface layer and the interior strengthened surface layer by irradiating the sidewall with a laser without separating the glass article.

Abstract: A method for preparing all-solid-state photonic crystal fiber preform by extrusion by aligning the center of the first jacking end of the first jacking rod with the center of the core outlet mold. The adverse effect on this part of extruded core glass by oxygen or other impurities in air during the extrusion out of the core outlets can be avoided. The defects on the core glass surface and the cladding glass surface can be effectively removed, and the purity and quality of the core component in the obtained fiber preform can be improved.

Abstract: A multiple tube burner for synthesizing a porous material includes three or more glass tubes are arranged coaxially with one another, the glass tubes having a substantially circular shape on a cross section perpendicular to a longitudinal direction. Out of the three or more glass tubes, a first glass tube and a second glass tube that is arranged on an outer side of the first glass tube are connected with each other on a gas introducing side, and a thickness near a joint portion of the second glass tube connected with the first glass tube is thicker than a thickness of the second glass tube on the gas spouting side.

Abstract: An optical fiber manufacturing method includes a first process of passing a glass fiber through a fiber path. The fiber path is formed through a cooling tube that is housed in a first casing. The method also includes a second process of leading the glass fiber into a second casing before leading into the first casing. The first process includes supplying a first dry gas, having a dew point lower than the temperature of the cooling tube, into a first dry space formed between the first casing and the cooling tube. The second process includes supplying a second dry gas into a second dry space formed inside the second casing so as to cause air pressure in the second dry space to be higher than air pressure in an external space. The dew point of the second dry gas is lower than the dew point in the external space.

Abstract: The invention discloses a preparation method and device of active microcrystalline fiber, place the prefabricated rod in the drawing furnace for wire drawing, the drawn fiber is induced by magnetic field in uncoated state and combined with laser treatment technology, the laser beam is focused on the fiber and recrystallized after laser treatment to obtain active microcrystalline fiber. Appropriate laser processing power directly affects the silicate glass fiber in the crystal structure, type, degree of crystallinity, grain size, content, and how much residual phase of glass. Induced by external magnetic field, the thermodynamics and dynamics of crystallization process are changed, make the crystal size distribution is better and uniform, reduce the phenomenon of condensation and makes the grain size is smaller.

Abstract: An optical fiber draw system and method of operating thereof. The method includes positioning a downfeed handle for supporting an optical fiber preform within a furnace such that the downfeed handle is movable within the furnace. The method further includes operating one or more heating elements to thermally heat at least a portion of an upper muffle extension disposed within the furnace, the one or more heating elements being moveable with the downfeed handle.

Abstract: Provided is a method for producing a glass material by a containerless levitation technique, which enables production of a large-sized glass material.

Abstract: One aspect relates to a process for the preparation of a quartz glass body including, providing a silicon dioxide granulate obtainable from a silicon dioxide powder, wherein the silicon dioxide granulate has a larger particle size than the silicon dioxide powder, making a 5 glass melt out of silicon dioxide granulate and making a quartz glass body out of at least part of the glass melt. The melting crucible has at least one inlet and at least one outlet. A least part of the glass melt is removed via the melting crucible outlet. One aspect further relates to a quartz glass body which is obtainable by this process. One aspect further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing 10 of the quartz glass body.

Abstract: One aspect relates to a process for the preparation of a quartz glass body. The process includes providing silicon dioxide particles, making a glass melt out of the silicon dioxide particles in an oven and making a quartz glass body out of at least part of the glass melt. The oven has a gas outlet through which gas is removed from the oven, wherein the dew point of the gas on exiting the oven through the gas outlet is less than 0° C. One aspect further relates to a quartz glass body which is obtainable by this process. One aspect further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

Abstract: Methods of producing a glass article include melting a first glass composition and feeding a second glass composition into the melter. Both glass compositions include the same combination of components but at least one component has a concentration that is different in each. At least three glass articles may be drawn from the melter, including: a first glass article formed from the first glass composition; at least one intermediate glass article composed of neither the first nor the second glass composition; and a final glass article not composed of the first glass composition. The concentration of the at least one component in the intermediate glass article may be between the concentration in the first and second glass compositions. The first glass article and final glass article may have differing values for certain properties, and the intermediate glass article may have an intermediate set of values for the same properties.

Abstract: A method of producing glass includes drawing unrefined foamy molten glass from a glass melt held in a submerged combustion melter and introducing the unrefined foamy molten glass into a stilling chamber of a stilling tank. An intermediate pool of molten glass is held within the stilling chamber of the stilling tank and is heated therein by one or more non-submerged burners. Molten glass flows from the intermediate pool of molten glass to a transfer pool of molten glass held in a spout chamber of a feeding spout that is appended to the stilling tank. A molten glass feed can be drawn from the transfer pool of molten glass and delivered from the feeding spout at a controlled rate.

Abstract: Various improvements for dual-elevation edge roll system used in fused downdraw glass forming process are disclosed.

Abstract: A pair of moulds for moulding an optical component is disclosed. The pair of moulds includes a first mould having a first surface, and a second mould having a second surface. The first surface includes a moulding portion for moulding a first optical surface of the optical component, and an alignment portion for alignment with the second mould. The alignment portion extends around the moulding portion. The second surface includes a moulding portion for moulding a second, opposite optical surface of the optical component, and an alignment portion for alignment with the first mould via a contact with the alignment portion of the first surface. When the moulds are brought together, they self-align. A corresponding moulding apparatus and a method may use the mould pair to manufacture various optical components.

Abstract: Methods for preform and tube draw based on controlling forming zone viscosity determined by calculating a holding force exerted by the glass component in the forming zone on the strand being drawn below. The holding force may be calculated by determining a gravitational force applied to the strand and a pulling force applied to the strand by a pulling device, where the holding force is equal to the opposite of the algebraic sum of the gravitational and pulling forces. The holding force may also be calculated by measuring a stress-induced birefringence in the strand at a point between the forming zone and the pulling device, determining an amount of force applied to the strand at the point corresponding to the birefringence, and calculating the holding force by correcting the amount of force for a gravitational effect of the weight of the strand between the forming zone and the point.

Abstract: A variable seal for shielding from contaminants both an object to be heated in, and the heating element of, a high-temperature furnace. The seal has a first support ring and a second support ring separated by a distance. One or more components control the distance between the two support rings. A high-temperature fabric cylinder is attached to the support rings, is located where the object enters or exits the furnace, and surrounds at least a portion of the object. A mechanism engages the approximate center of the fabric cylinder to close the fabric cylinder as the one or more components decrease the distance between the two support rings and to open the fabric cylinder as the one or more components increase the distance between the two support rings, whereby the fabric cylinder continuously contacts the circumference of the object regardless of the diameter of the object.

Abstract: A method of forming a glass article includes providing a first glass sheet. The first glass sheet is heated to a temperature suitable for shaping. The first glass sheet is deposited on a first bending tool. An edge portion of the first glass sheet is disposed over a shaping surface of the first bending tool. The shaping surface of the first bending tool is configured to provide in the first glass sheet a compression area and a tension area. The first glass sheet is shaped on the first bending tool and the compression area is formed in the edge portion of the first glass sheet. The compression area includes a first portion and a second portion. The first portion has a width which is greater than a width of a second portion.

Abstract: A manufacturing apparatus of a porous glass base material for optical fiber includes: a liquid mass flow controller for controlling a flow rate of a raw material liquid of an organic siloxane; a vaporizer for mixing the raw material liquid and a carrier gas to vaporize the raw material liquid to form a mixed gas in which a raw material gas and the carrier gas are mixed; a raw material liquid nozzle for ejecting the raw material liquid into the vaporizer; a carrier gas supply pipe for supplying the carrier gas into the vaporizer; a raw material liquid pipe for introducing the raw material liquid into the raw material liquid nozzle; a burner for combusting the mixed gas together with a combustible gas and a combustion supporting gas to produce SiO2 fine particles; a mixed gas pipe; an open/close valve; and a purge gas supply pipe.

Abstract: A submerged combustion melter and system are disclosed. The submerged combustion melter includes a bottom wall, at least one side wall extending upwardly from the bottom wall, a crown extending inwardly with respect to the at least one side wall and over the bottom wall to establish a melting chamber, an exhaust port configured to exhaust gas from the melting chamber, at least one baffle extending from the at least one side wall to divide the melting chamber into melting sub-chambers that share the exhaust port, at least one inlet configured for introducing a glass batch into the submerged combustion melter, and at least one outlet configured to remove molten glass from the at least one melting chamber.

Abstract: Methods of reshaping ferrules used in optical fiber cables assemblies are disclosed. The reshaping methods reduce a core-to-ferrule concentricity error (E), which improves coupling efficiency and optical transmission. The methods include measuring a true center of the ferrule, wherein the true center is based on an outer surface of the ferrule; and reshaping at least a portion of the ferrule to change the true center of the ferrule, wherein the reshaping includes enlarging a portion of the ferrule. A variety of reshaping techniques are also disclosed.

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.