Patent application number | Description | Published |
20100162768 | METHOD AND APPARATUS FOR MANUFACTURING OPTICAL FIBER PREFORM USING HIGH FREQUENCY INDUCTION THERMAL PLASMA TORCH - Provided is an optical fiber preform manufacturing method comprising supplying a high-frequency induction thermal plasma torch with at least glass raw material, dopant raw material, and oxygen, and depositing the glass particles synthesized in the plasma flame onto a surface of a glass rod that moves backward and forward relative to the plasma torch while rotating, wherein the plasma flame is narrowed such that at least a portion of the glass particles continuously formed by the plasma flame are not deposited on the glass rod. As a result, the fluorine concentration in the cladding is increased to improve the relative refractive index difference of the preform. | 07-01-2010 |
20100162769 | METHOD AND APPARATUS FOR MANUFACTURING OPTICAL FIBER PREFORM USING HIGH FREQUENCY INDUCTION THERMAL PLASMA TORCH - Provided is an apparatus and method for manufacturing an optical fiber preform by supplying a high-frequency induction thermal plasma torch with at least glass raw material, dopant raw material, and oxygen, and depositing the glass particles synthesized in the plasma flame onto a surface of a glass rod that moves backward and forward relative to the plasma torch while rotating, wherein deposition of the glass particles is performed while cooling the glass rod. As a result, the concentration of fluorine doped in the cladding increase, thereby improving the relative refractive index of the preform. | 07-01-2010 |
20100207333 | SEAL MEMBER - Provided is a seal member, which is used in a heating furnace having an insertion port to which an end of a rod to be heated is inserted and seals between the insertion port and a surface of the rod inserted to the insertion port in an airtight manner, the seal member having: a plurality of seal chips in thin strips arranged along an inner surface of the insertion port in an airtight manner, each seal chip having one end held by the inner surface of the insertion port and the other end elongated towards inside the insertion port, where (a) when the rod is not inserted in the insertion port, each of the plurality of seal chips forms a slanting angle with respect to an insertion direction of the rod and (b) when the rod is inserted in the insertion port, the other end of each of the plurality of seal chips is pressed against a surface of the rod by means of elastic deformation. | 08-19-2010 |
20110016926 | METHOD OF MANUFACTURING OPTICAL FIBER PREFORM USING PLASMA TORCH - A method of manufacturing an optical fiber preform by depositing glass fine particles onto a surface of a glass rod while the glass rod is reciprocated relative to a plasma torch, including: moving the glass rod in a first direction relative to the plasma torch while the plasma torch is applied to the glass rod and supplied at least with a dopant material and a glass material to deposit the glass fine particles onto the surface of the glass rod, in such a manner that a plasma power is set higher during a first time interval starting from a beginning of the movement of the glass rod in the first direction than during a second time interval starting from an end of the first time interval; and moving the glass rod in a second direction relative to the plasma torch, where the second direction is opposite to the first direction. | 01-27-2011 |
20110162413 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL - Provided is a method of manufacturing an optical fiber base material having at least four layer including a core, a first cladding, a second cladding containing fluorine, and a third cladding. The manufacturing method comprises preparing a starting base material that includes the core and the first cladding; forming a porous intermediate glass base material by supplying glass raw material and oxygen to a high-frequency induction thermal plasma torch to synthesize glass fine particles that are then deposited on a surface of the starting base material; forming an intermediate glass base material that includes the core, the first cladding, and the second cladding containing fluorine, by heating and vitrifying the porous intermediate glass base material in an atmosphere containing fluorine; and providing the third cladding on the outer surface of the intermediate glass base material. | 07-07-2011 |
20120186302 | GLASS LATHE - Provided is a glass lathe that processes a glass member by heating the glass member with a burner, wherein a reflector that reflects electromagnetic waves is arranged around a portion of the glass member to be heated. The reflector preferably has a spherical surface with a portion removed therefrom, and may be formed of a mirror surface finishing agent for SUS, aluminum, or an aluminum alloy. An inner surface of the reflector is preferably covered by gold, platinum, or rhodium, and an outer surface of the reflector is preferably processed to improve thermal emittance, by applying an infrared light emitting coating thereto. | 07-26-2012 |
20120222452 | ELONGATING METHOD AND APPARATUS FOR GLASS BASE MATERIAL - A method of elongating a glass base material to obtain a glass rod having a smaller diameter, using a glass base material elongating apparatus including a feeder at least for the glass base material, a heating furnace, and an elongating mechanism of the glass base material below the heating furnace, is such that a horizontal plane position measuring unit of the glass base material is provided inside or near the heating furnace, the feeder has a glass base material horizontal plane position adjusting unit, and the elongating mechanism has three or more sets of elongating rollers capable of switching between grasping and releasing for keeping the position of the glass rod in the horizontal plane to be constant, and the glass base material is elongated with the position thereof in the horizontal plane kept as targeted by controlling the glass base material horizontal plane position adjusting unit. | 09-06-2012 |
20130186148 | GLASS BASE MATERIAL ELONGATING METHOD AND GLASS BASE MATERIAL ELONGATING APPARATUS - Provided is a glass base material elongating method of using a glass base material elongation apparatus including a heating furnace, a feeding mechanism, and a pulling mechanism to elongate the rod-shaped glass base material to form a thinner glass rod, the method comprising gripping a pulling dummy rod connected to a bottom end of the glass base material with first pulling rollers of the pulling mechanism and, together with the feeding mechanism, feeding the glass base material to the heating furnace; and before a pulling force necessary for pulling the pulling dummy rod to elongate the glass base material reaches a load force that causes slipping between the pulling dummy rod and the first pulling rollers, gripping and pulling the pulling dummy rod with second pulling rollers of the pulling mechanism in addition to the first pulling rollers. | 07-25-2013 |
20130291601 | GLASS BASE MATERIAL ELONGATING METHOD AND GLASS BASE MATERIAL ELONGATING APPARATUS - A glass base material elongating method of sequentially feeding rod-like glass base materials hung by a glass base material feeding mechanism into a heating furnace, and pulling a glass rod with a smaller diameter by a pulling chuck at a lower part of the heating furnace, includes: aligning, by an alignment guiding device that guides the glass rod, a guiding center of the alignment guiding device with an axis of the glass rod, the alignment guiding device guiding the glass rod between the heating furnace and the pulling chuck. | 11-07-2013 |
20140020430 | GLASS BASE MATERIAL ELONGATION METHOD - Provided is a glass base material elongation method for elongating a glass base material with a large diameter to manufacture a glass rod with a smaller diameter, the method comprising, when elongating a glass base material that has a transparent glass tapered portion at one end of a trunk portion and a glass tapered portion including a non-transparent glass portion at the other end of the trunk portion, prior to the elongation, fusing a hanging dummy to an end of the transparent glass tapered portion, setting the hanging dummy in communication with a feeding mechanism, inserting the glass base material into a heating furnace beginning with the other end, and performing elongation. | 01-23-2014 |
20140096566 | GLASS BASE MATERIAL ELONGATING APPARATUS - In order to provide a glass base material elongating apparatus that can safely elongate a glass base material in an extendable top chamber without damaging a flange, provided is a glass base material elongating apparatus comprising a heating furnace; an extendable top chamber formed of a multilayer cylinder disposed above the heating furnace; a glass base material hanging mechanism that hangs a glass base material into the heating furnace and the extendable top chamber; and a top chamber lifting mechanism. A flange is formed on a top portion of an outermost tube of the multilayer cylinder, and the top chamber lifting mechanism includes a cylinder support member that supports the flange from below and a cylinder lifting member that lifts up the cylinder support member. | 04-10-2014 |
20140097567 | GLASS BASE MATERIAL HANGING MECHANISM - Provided is a glass base material hanging mechanism that, when hanging a starting member or a glass base material, can tightly (solidly) connect the hanging shaft tube and the hanging component and can vertically align the hanging component and the center of the glass base material. | 04-10-2014 |
Patent application number | Description | Published |
20080295541 | METHOD OF MANUFACTURING AN OPTICAL FIBER PREFORM USING A HIGH FREQUENCY INDUCTION THERMAL PLASMA - When manufacturing an optical fiber preform by feeding at least glass raw material, dopant material and oxygen gas to a high frequency induction thermal plasma torch to synthesize glass particles in plasma therein, a glass rod is rotated and reciprocated relative to the plasma torch to deposit the synthesized glass particles onto the glass rod. The fluctuation of the relative refractive-index difference in the longitudinal direction of the optical fiber preform is suppressed and the average value of the relative refractive-index difference in the longitudinal direction is enhanced. The glass raw material is fed to the plasma torch in a forward direction of the reciprocating motion of the glass rod, and a feeding amount of the glass raw material in the backward direction of the reciprocating motion is reduced relative to the feeding amount in the forward direction. | 12-04-2008 |
20090025431 | FURNACE FOR FABRICATING A GLASS PREFORM OR AN OPTICAL FIBER - In a furnace for heating an optical fiber preform to be inserted from an insertion opening, the furnace includes an annular sealing body for sealing a clearance gap between the optical fiber preform and the insertion opening. The annular sealing body is formed from stacked annular disks respectively having an insertion hole in its center area. The annular disk has slits formed from a inner edge of the annular disk toward its periphery side and flexible portions that are defined by the slits and bend by an interference with the optical fiber preform to be inserted into the insertion hole. When the optical fiber preform is inserted into the insertion hole of the annular sealing body, the flexible portions bend. | 01-29-2009 |
20090038345 | APPARATUS FOR FABRICATING AN OPTICAL FIBER AND METHOD FOR SEALING A DRAWING FURNACE - In an apparatus for fabricating an optical fiber, the apparatus includes a drawing furnace provided with an insertion opening for receiving an optical fiber perform, a feed mechanism configured to support one end of the optical fiber preform so as to feed into the drawing furnace, a first sealing unit configured to seal a clearance gap between the optical fiber preform and the insertion opening, and a second sealing unit configured to seal a gap between the optical fiber preform and the first sealing unit when a tapered portion formed at the one end side of the optical fiber preform passes through the insertion opening. As a result, the available entirety of the optical fiber preform can be changed to an optical fiber, so that the cost for fabricating the optical fiber can be significantly reduced. | 02-12-2009 |
20110132039 | GLASS PREFORM DRAWING APPARATUS - A glass preform drawing apparatus feeds a glass preform into a heating furnace at a predetermined feeding speed and produces a glass rod having a uniform diameter. Specifically, the drawing apparatus for producing a glass rod having a desired outer diameter by heating and drawing a glass preform is characterized in that, at a normal operating temperature T (K) of the heating furnace, the top chamber is transparent at a wavelength of λ (μm) expressed by the following formula 1: | 06-09-2011 |
20120055198 | APPARATUS FOR FABRICATING A GLASS ROD AND METHOD OF SAME - The present invention provides a apparatus and a method for fabricating a glass rod capable of suppressing a diameter fluctuation of a drawn glass rod even in case of a relatively large diameter reduction ratio between a glass preform and a glass rod, such as 60 to 95%. A feed speed V | 03-08-2012 |
20120057834 | Optical Fiber, Optical Fiber Preform and Method of Fabricating Same - An optical fiber capable of suppressing an increase of a transmission loss after exposure of the optical fiber to hydrogen or deuterium is provided. The optical fiber has a core region, an inner cladding region surrounding the core region, a trench region surrounding the inner cladding region, an outer cladding region surrounding the trench region, and a refractive index varying region arranged between the inner cladding region and the trench region, the refractive index varying region having a refractive index gradually increasing from the trench region to the inner cladding region. | 03-08-2012 |
20120060560 | APPARATUS FOR FABRICATING A GLASS ROD AND METHOD OF SAME - The present invention provides an apparatus and a method for fabricating a glass rod capable of suppressing a diameter fluctuation of a drawn glass rod even in a case of a relatively large diameter reduction ratio between a glass preform and a glass rod, such as 60 to 95%. The diameter (D) of the glass preform for determining the ratio from a measured diameter data is acquired, the measured diameter data is obtained by measuring a diameter of the glass preform before being drawn along a longitudinal direction of the preform, and the feed speed (V1) is determined so that the feed speed (V1) varies depending on a fluctuation of the measured diameter data in the longitudinal direction. | 03-15-2012 |