Inert, Nonoxidizing, Or Reducing Environment Patents (Class 65/424)
  • Patent number: 9085482
    Abstract: 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.
    Type: Grant
    Filed: October 1, 2013
    Date of Patent: July 21, 2015
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventor: Tetsuya Otosaka
  • Patent number: 8631669
    Abstract: An optical fiber manufacturing apparatus including: a heating furnace in which an optical fiber is formed by melt-drawing an optical fiber preform; a sealing mechanism which is provided on an opening portion located at an upstream of the heating furnace and seals the heating furnace with an inert gas; a first pipe which is connected to the heating furnace and introduces the gas into the heating furnace; a second pipe which is connected to a lowermost compartment closest to the heating furnace among the compartments and introduces the gas into the lowermost compartment; and a gas flow rate control unit which controls a total sum of a flow rate of a gas supplied from the first pipe into the heating furnace and a flow rate of a gas supplied from the second pipe into the lowermost compartment to be substantially constant.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: January 21, 2014
    Assignee: Fujikura Ltd.
    Inventor: Kenji Okada
  • Publication number: 20130340483
    Abstract: A gas supplying unit supplies a nitrogen gas into a furnace body of a graphite heating furnace in which at least a part of the furnace body is formed with a graphite. An exhausting unit exhausts a gas inside the furnace body to outside the furnace body. A dew-point temperature of the nitrogen gas supplied into the furnace body is equal to or lower than ?80° C. A pressure inside the furnace body is equal to or higher than 140 Pa with respect to an atmospheric pressure outside the furnace body.
    Type: Application
    Filed: August 27, 2013
    Publication date: December 26, 2013
    Applicant: Furukawa Electric Co., Ltd.
    Inventor: Tadashi TAKAHASHI
  • Patent number: 8607592
    Abstract: An optical fiber manufacturing apparatus including: a heating furnace in which an optical fiber is formed by melt-drawing an optical fiber preform; a sealing mechanism which is provided on an opening portion located at an upstream of the heating furnace and seals the heating furnace with an inert gas; a first pipe which is connected to the heating furnace and introduces the gas into the heating furnace; a second pipe which is connected to a lowermost compartment closest to the heating furnace among the compartments and introduces the gas into the lowermost compartment; and a gas flow rate control unit which controls a total sum of a flow rate of a gas supplied from the first pipe into the heating furnace and a flow rate of a gas supplied from the second pipe into the lowermost compartment to be substantially constant.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: December 17, 2013
    Assignee: Fujikura Ltd.
    Inventor: Kenji Okada
  • Publication number: 20130298611
    Abstract: A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a synthetic quartz glass vessel at least partly made of quartz glass which contains aluminum equal to or less than 0.01 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating a portion made of quartz glass which contains aluminum equal to or less than 0.01 ppm in the vessel that contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material.
    Type: Application
    Filed: July 22, 2013
    Publication date: November 14, 2013
    Applicant: c/o Shin-Etsu Chemical Co., Ltd.
    Inventors: Dai Inoue, Hiroyuki Koide, Takaaki Nagao
  • Patent number: 8573008
    Abstract: An optical fiber production system and method are provided for producing optical fiber. An optical fiber is drawn from a preform in a furnace and passes through a treatment device under a reduced pressure in the range of 0.01 to 0.80 atm. The treatment device cools the bare optical fiber as it cools to a temperature in the range of at least 1,600° C. to 1,300° C. A non-contact fiber centering device is located near an exit of the treatment device to provide centering of the optical fiber as it exits the treatment device.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: November 5, 2013
    Assignee: Corning Incorporated
    Inventors: James Henry Faler, Andrey V Filippov, Robert C Moore, Bruce Warren Reding
  • Patent number: 8418504
    Abstract: Disclosed is a method of fabricating an optical fiber or an optical device doped with reduced metal ion and/or rare earth ion, comprising steps of: forming a partially-sintered fine structure in a base material for fabricating the optical fiber or the optical device; soaking the fine structure into a doping solution containing a reducing agent together with metal ion and rare earth ion during a selected time; drying the fine structure in which the metal ion and/or rare ion are/is soaked; and heating the fine structure such that the fine structure is sintered.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: April 16, 2013
    Assignees: Optonest Corporation, K-JIST (Kwangju Institute of Science and Technology)
    Inventors: Won-Taek Han, Yune-Hyoun Kim, Tae-Jung Ahn
  • Patent number: 8402789
    Abstract: A method of producing a thermally stable grating allows the grating to be placed in environments where temperatures reach 1000° C. These gratings may be concatenated so as to form a sensor array. The method requires a step of lowering the characteristic intensity threshold of a waveguide by at least 25%, followed by irradiating the waveguide with femtosecond pulses of light having a sufficient intensity and for a sufficient duration to write the grating so that at least 60% of the grating remains after exposures of at least 10 hours at a temperature of at least 1000° C. Pre-writing a Type I grating before writing a minimal damage Type II grating lowers the characteristic threshold of the waveguide so that a stable low damage type II grating can be written; alternatively providing a hydrogen or deuterium loaded waveguide before writing the grating lowers the characteristic threshold of the waveguide.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: March 26, 2013
    Assignee: Her Majesty the Queen in Right of Canada, as Represented by the Minister of Industry, Through the Communications Research Centre Canada
    Inventors: Christopher W. Smelser, Stephen J. Mihailov, Dan Grobnic, Ping Lu, Robert B. Walker, Gino Cuglietta, Huimin Ding, Xiaoli Dai
  • Patent number: 8272236
    Abstract: A method of producing a thermally stable grating allows the grating to be placed in environments where temperatures reach 1000° C. and where the grating is relatively stable and has very low loss from scatter. These gratings have spectral characteristics that allow them to be concatenated so as to form a sensor array. The method requires a step of lowering the characteristic intensity threshold of a waveguide by at least 25%, followed by irradiating the waveguide with femtosecond pulses of light having a sufficient intensity and for a sufficient duration to write the grating so that at least 60% of the grating remains after exposures of at least 10 hours at a temperature of at least 1000° C.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: September 25, 2012
    Assignee: Her Majesty the Queen in right of Canada, as represented by the Minister of Industry, through the Communications Research Centre Canada
    Inventors: Christopher W. Smelser, Stephen J. Mihailov, Dan Grobnic, Ping Lu, Robert B. Walker, Gino Cuglietta, Haimin Ding, Xiaoli Dai
  • Publication number: 20120219260
    Abstract: A method for manufacturing deuterium-treated silica glass includes exposing silica glass to a deuterium-containing atmosphere for a predetermined period of time to diffuse deuterium molecules within the silica glass, maintaining the silica glass at 40° C. or higher, and cooling the silica glass to room temperature. The silica glass is a silica glass-based optical fiber having a core made of silica glass, where the core is positioned at a center of the optical fiber and contains at least germanium, and a clad made of silica glass, where the clad surrounds the core and has a lower refractive index than the core. A surface of the silica glass is covered with a resin coating.
    Type: Application
    Filed: February 24, 2012
    Publication date: August 30, 2012
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventor: Hiroshi OYAMADA
  • Patent number: 8230702
    Abstract: Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: July 31, 2012
    Assignee: Draka Comteq, B.V.
    Inventors: Guangjun Xu, Larry Zeng, Ivo Flammer, Dennis Robert Simons, Cedric Gonnet, Rob Hubertus Matheus Deckers
  • Publication number: 20120000249
    Abstract: Provided is a method for producing an optical fiber preform including a dehydration step and a sintering step. In the dehydration step, a porous glass base material is provided to a furnace core tube of a dehydration-sintering furnace, and the porous glass base material is dehydrated using a dehydration agent added with an argon gas. In the sintering step, the porous glass base material dehydrated in the dehydration step is sintered. Further, in the dehydration step, a temperature of the porous glass base material begins to be increased in a condition such that a high heat conductivity gas, having a heat conductivity higher than a heat conductivity of the argon gas, is remaining inside the porous glass base material.
    Type: Application
    Filed: September 9, 2011
    Publication date: January 5, 2012
    Applicant: FUJIKURA LTD.
    Inventor: Takahiro HAMADA
  • Publication number: 20110289979
    Abstract: An optical fiber production system and method are provided for producing optical fiber. An optical fiber is drawn from a preform in a furnace and passes through a treatment device under a reduced pressure in the range of 0.01 to 0.80 atm. The treatment device cools the bare optical fiber as it cools to a temperature in the range of at least 1,600° C. to 1,300° C. A non-contact fiber centering device is located near an exit of the treatment device to provide centering of the optical fiber as it exits the treatment device.
    Type: Application
    Filed: April 21, 2011
    Publication date: December 1, 2011
    Inventors: James Henry Faler, Andrey V. Filippov, Robert C. Moore, Bruce Warren Reding
  • Patent number: 8065893
    Abstract: A process and apparatus for making silicon or silicon/germanium core fiber is described, which uses a plasma process with reducing agent to make a preform. The process also makes the recommendations in selecting the adequate cladding tube for better fiber properties. An improved fiber drawing apparatus is also disclosed in order to draw this new type of preform.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: November 29, 2011
    Inventor: Dau Wu
  • Publication number: 20110265522
    Abstract: An optical fiber manufacturing apparatus including: a heating furnace in which an optical fiber is formed by melt-drawing an optical fiber preform; a sealing mechanism which is provided on an opening portion located at an upstream of the heating furnace and seals the heating furnace with an inert gas; a first pipe which is connected to the heating furnace and introduces the gas into the heating furnace; a second pipe which is connected to a lowermost compartment closest to the heating furnace among the compartments and introduces the gas into the lowermost compartment; and a gas flow rate control unit which controls a total sum of a flow rate of a gas supplied from the first pipe into the heating furnace and a flow rate of a gas supplied from the second pipe into the lowermost compartment to be substantially constant.
    Type: Application
    Filed: April 20, 2011
    Publication date: November 3, 2011
    Applicant: FUJIKURA LTD.
    Inventor: Kenji OKADA
  • Publication number: 20110226020
    Abstract: Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
    Type: Application
    Filed: May 23, 2011
    Publication date: September 22, 2011
    Applicant: DRAKA COMTEQ B.V.
    Inventors: Guangjun Xu, Larry Zeng, Ivo Flammer, Dennis Robert Simons, Cedric Gonnet, Rob Hubertus Matheus Deckers
  • Patent number: 8015847
    Abstract: An optical fiber apparatus and manufacturing method thereof includes: forming a bare optical fiber by melting and deforming an optical fiber preform; cooling the bare optical fiber after the bare optical fiber forming step by passing it through a flow channel of a cooling unit through which cooling gas flows; and forming a protective coating layer by supplying a molten resin to a periphery of the bare optical fiber after the cooling step thereby forming an optical fiber. The cooling gas flowing toward a vertically lower end of the flow channel is blocked by the molten resin used to form the protective coating layer, and carbon dioxide gas is supplied toward the flow channel from a position which is vertically below the supply position of the cooling gas and vertically above the blocking position of the molten resin.
    Type: Grant
    Filed: April 29, 2009
    Date of Patent: September 13, 2011
    Assignee: Fujikura Ltd.
    Inventors: Kenji Okada, Shingo Matsushita
  • Patent number: 8003644
    Abstract: Biocidal compositions that contain biocidal components, such as an oxidant, and mixed with said components a combination of inorganic compounds capable of reducing the oxidative capacity of the biocidal components by forming a low-melting glass when heated. The biocidal composition may be heated by being ignited or subjected to a heating source, such as a fire.
    Type: Grant
    Filed: April 8, 2004
    Date of Patent: August 23, 2011
    Assignee: Bromine Compounds Ltd.
    Inventor: Theodor Morel Fishler
  • Patent number: 7946135
    Abstract: Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
    Type: Grant
    Filed: January 2, 2008
    Date of Patent: May 24, 2011
    Assignees: Draka Comteq, B.V., Momentive Performance Materials, Inc.
    Inventors: Guangjun Xu, Larry Zeng, Ivo Flammer, Dennis Robert Simons, Cedric Gonnet, Rob Hubertus Matheus Deckers
  • Patent number: 7946132
    Abstract: A method for manufacturing an optical fiber preform and an optical fiber preform apparatus are provided which can reduce hydroxyl groups in an optical fiber preform to a sufficient level without requiring any special equipment or operating conditions. When an optical fiber preform is manufactured by the vapor-phase deposition method, the dehydrating treatment is performed on a porous core preform that is obtained by depositing glass microparticles. In this treatment, a dehydrating agent is supplied to a dehydration apparatus through a feeding pipe and a main feeding pipe made of a material having a water permeance factor of 1.0×10?11 g·cm/cm2·s·cmHg or less, thereby manufacturing an optical fiber preform.
    Type: Grant
    Filed: March 5, 2009
    Date of Patent: May 24, 2011
    Assignee: Fujikura Ltd.
    Inventors: Manabu Saitou, Shunichirou Hirafune
  • Patent number: 7930904
    Abstract: Microstructured optical fiber and method of making. Glass soot is deposited and then consolidated under conditions which are effective to trap a portion of the consolidation gases in the glass to thereby produce a non-periodic array of voids which may then be used to form a void containing cladding region in an optical fiber. Preferred void producing consolidation gases include nitrogen, argon, CO2, oxygen, chlorine, CF4, CO, SO2 and mixtures thereof.
    Type: Grant
    Filed: October 2, 2008
    Date of Patent: April 26, 2011
    Assignee: Corning Incorporated
    Inventors: Dana Craig Bookbinder, Richard Michael Fiacco, Ming-Jun Li, Michael Thomas Murtagh, Pushkar Tandon
  • Patent number: 7921676
    Abstract: A method for manufacturing an optical fiber preform and an optical fiber preform apparatus are provided which can reduce hydroxyl groups in an optical fiber preform to a sufficient level without requiring any special equipment or operating conditions. When an optical fiber preform is manufactured by the vapor-phase deposition method, the dehydrating treatment is performed on a porous core preform that is obtained by deposing glass microparticles. In this treatment, a dehydrating agent is supplied to a dehydration apparatus through a feeding pipe and a main feeding pipe made of a material having a water permeance factor of 1.0×10?11 g·cm/cm2·s·cmHg or less, thereby manufacturing an optical fiber preform.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: April 12, 2011
    Assignee: Fujikura Ltd.
    Inventors: Manabu Saitou, Shunichirou Hirafune
  • Patent number: 7752870
    Abstract: A method of forming an optical fiber preform using, for example, an MCVD process, is modified to reduce the presence of hydrogen-induced transmission losses in an optical fiber drawn from the preform. A relatively porous, unsintered soot layer is first formed (similar to the initial soot layer commonly associated with the solution-doped process of the prior art) and then subjected to a flow of a metal halide (such as SiCl4) to reduce the presence of excess oxygen. It is imperative that the metal halide treatment occur in the absence of oxygen. Sintering of the treated layer, followed by a conventional collapsing process is then used to form the inventive preform. In accordance with the present invention, both the sintering and collapsing steps are performed in a non-oxygen based ambient. When the drawn fiber is then later exposed to hydrogen, the lack of oxygen thus eliminates the formation of Si—OH and the associated attenuation problems.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: July 13, 2010
    Assignee: Baker Hughes Incorporated
    Inventor: Daniel Scott Homa
  • Publication number: 20100043497
    Abstract: An optical fiber having a length of 1 km or more with average transmission loss in a wavelength band of 1383 nm being less than average transmission loss in a wavelength band of 1310 nm, wherein a maximum value of any 1 km section loss in the wavelength band of 1383 nm does not exceed the average transmission loss by 0.03 dB/km or more.
    Type: Application
    Filed: October 13, 2009
    Publication date: February 25, 2010
    Applicant: Furukawa Electric Co., Ltd.
    Inventors: Fumio Takahashi, Masahide Kuwabara, Yoshinori Ishida, Masato Oku
  • Patent number: 7657142
    Abstract: The invention concerns a method for making an optical fiber (18) including the following steps: producing a preform (10) containing nanoparticles provided with an active element including at least one recess (14) proximate at least part of the nanoparticles; fiber drawing of the preform (10) by introducing a non-oxidizing gas in the recess (14), thereby limiting the risks of oxidizing the nanoparticles of the preform (10). The preform (10) designed to the manufacture of an optical fiber (18) by the inventive method comprises nanoparticles provided with an active element in a doped zone (12) and at least one recess (14) proximate the doped zone (12).
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: February 2, 2010
    Assignee: Alcatel Lucent
    Inventors: Laurent Gasca, Stéphanie Blanchandin, Alain Pastouret, Christian Simonneau
  • Publication number: 20090247388
    Abstract: The present invention provides a fluorophosphate glass containing phosphorus, oxygen and fluorine as glass ingredients, in which, provided that a refractive index nd of the glass is nd(1) and a refractive index nd after re-melting the glass at 900° C. for 1 hour in a nitrogen atmosphere, cooling the glass to a glass transition temperature and then cooling the glass down to 25° C. at a temperature decrease rate of 30° C. per hour is nd(2), an absolute value of a difference between nd(1) and nd(2) (nd(2)-nd(1)) is equal to or less than 0.00300, and a molar ratio (O2?/P5+) of a content of O2? to a content of P5+ is equal to or more than 3.5. The glass of the invention is reduced in volatility and erosiveness.
    Type: Application
    Filed: March 27, 2009
    Publication date: October 1, 2009
    Applicant: HOYA CORPORATION
    Inventor: Mikio Ikenishi
  • Publication number: 20090211302
    Abstract: A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a vessel which employs a composite tube, the composite tube including a portion formed by jacketing a first quartz glass containing aluminum equal to or less than 0.01 ppm with a second quartz glass containing aluminum equal to or more than 15 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating the jacketed portion in the vessel which contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material.
    Type: Application
    Filed: December 22, 2008
    Publication date: August 27, 2009
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Dai Inoue, Hiroyuki Koide, Takaaki Nagao
  • Patent number: 7546750
    Abstract: Embodiments of the invention include a method for making optical fiber having reduced aging or hydrogen aging loss over the life of the fiber and optical fiber systems including such optical fibers. Improved silicon-oxygen stoichiometry during one or more preform manufacturing steps reduces the amount of Si defects generated in the optical fiber preform. Also, deuterium exposure of optical fiber drawn from the preform reduces the likelihood of having atomic defects such as Si defects in the optical fiber that, over time, attract and bond with hydrogen atoms to form molecules that contribute to increased water absorption loss. The inventive method produces optical fibers with improved transmission characteristics, e.g., optical fibers made by methods according to embodiments of the invention have transmission loss at 1385 nanometers that is less than 0.33 dB/km and the aging loss increase thereafter is less than 0.04 dB/km.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: June 16, 2009
    Assignee: Fitel USA Corp.
    Inventors: Kai H. Chang, David Kalish, Thomas John Miller
  • Publication number: 20090145169
    Abstract: A furnace for drawing an optical fiber includes a body having an upper and lower openings for supplying a preform and discharging a drawn optical fiber, a heating unit installed in the body for receiving and melting the preform, an atmosphere blocking tube installed to the lower opening for discharging the drawn optical fiber and blocking the optical fiber from the atmosphere, an upper introduction port formed at an upper portion of the body for introducing an inert gas toward the preform and partially discharged outside through a gap between the preform and the upper opening, a central and lower introduction ports formed at central and lower portions for introducing an inert gas into the body, a first flow guiding means for guiding the inert gas introduced through the central introduction port upward and then flowed down along a surface of the preform, and a second flow guiding means for guiding the inert gas introduced through the lower introduction port upward and then discharged outside through the atmosp
    Type: Application
    Filed: February 3, 2009
    Publication date: June 11, 2009
    Applicant: LG Cable
    Inventors: Sang-Joon Bae, Young-II Kwon, Joon-Keun Lee, Chul-Min Kim, Myung-Ho Jang
  • Publication number: 20090100876
    Abstract: A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a synthetic quartz glass vessel at least partly made of quartz glass which contains aluminum equal to or less than 0.01 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating a portion made of quartz glass which contains aluminum equal to or less than 0.01 ppm in the vessel that contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material.
    Type: Application
    Filed: December 22, 2008
    Publication date: April 23, 2009
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Dai Inoue, Hiroyuki Koide, Takaaki Nagao
  • Publication number: 20090038345
    Abstract: 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.
    Type: Application
    Filed: August 11, 2008
    Publication date: February 12, 2009
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Tetsuya OTOSAKA, Yoshiaki SHIMIZU
  • Publication number: 20080282743
    Abstract: Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
    Type: Application
    Filed: January 2, 2008
    Publication date: November 20, 2008
    Applicant: DRAKA COMTEQ B.V.
    Inventors: Guangjun Xu, Larry Zeng, Ivo Flammer, Dennis Robert Simons, Cedric Gonnet, Rob Hubertus Matheus Deckers
  • Publication number: 20080285927
    Abstract: A method for manufacturing an optical fiber having uniform refractive index profile, and substantially reduced macrobending loss and attenuation loss is provided comprising controlling one or more of parameters including concentration of dopant in outer region and inner region of the core region with respect to middle region of the core region of the optical fiber preform, duration of dehydration process step, concentration of chlorine gas to control refractive index of outer region and inner region of the core region for achieving a fiber having substantially uniform refractive index profile, and substantially reduced macrobending loss and attenuation loss.
    Type: Application
    Filed: April 20, 2007
    Publication date: November 20, 2008
    Applicant: STERLITE OPTICAL TECHNOLOGIES LTD.
    Inventors: Amjad Khan, Sanket Shah, Jegan Miras
  • Publication number: 20080285930
    Abstract: The invention concerns a method for making an optical fiber (18) including the following steps: producing a preform (10) containing nanoparticles provided with an active element including at least one recess (14) proximate at least part of the nanoparticles; fiber drawing of the preform (10) by introducing a non-oxidizing gas in the recess (14), thereby limiting the risks of oxidizing the nanoparticles of the preform (10). The preform (10) designed to the manufacture of an optical fiber (18) by the inventive method comprises nanoparticles provided with an active element in a doped zone (12) and at least one recess (14) proximate the doped zone (12).
    Type: Application
    Filed: August 28, 2006
    Publication date: November 20, 2008
    Applicant: Alcatel Lucent
    Inventors: Laurent Gasca, Stephanie Blanchandin, Alain Pastouret, Christian Simonneau
  • Patent number: 7312170
    Abstract: The present invention provides an optical synthetic quartz glass material which substantially does not cause changes in transmitted wave surface (TWS) by solarization, compaction (TWS delayed), rarefaction (TWS progressed) and photorefractive effect when ArF excimer laser irradiation is applied at a low energy density, e.g. at energy density per pulse of 0.3 mJ/cm2 or less. The present invention further provides a method for manufacturing the same. In order to solve the above-mentioned problems, the optical synthetic quartz glass material of the present invention is characterized in that, in a synthetic quartz glass prepared by a flame hydrolysis method using a silicon compound as a material, the followings are satisfied that the amount of SiOH is within a range of more than 10 ppm by weight to 400 ppm by weight, content of fluorine is 30 to 1000 ppm by weight, content of hydrogen is 0.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: December 25, 2007
    Assignees: Heraeus Quarzglas GmbH & Co. KG, Shin-Etsu Quartz Products Co., Ltd.
    Inventors: Hiroyuki Nishimura, Akira Fujinoki
  • Patent number: 7143612
    Abstract: To provide a method for producing a glass particle deposit and a method for producing a glass preform, in which outer diameter variation of the glass particle deposit can be reduced to thereby improve quality. A flow rate of clean gas (CG) introduced into a container potion 10 is limited to thereby prevent the outermost layer of a glass particle deposit 20 from being locally cooled and reduce variation in bulk density in the longitudinal direction of the glass particle deposit 20, that is, outer diameter variation and breakage.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: December 5, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Tomohiro Ishihara
  • Patent number: 7022633
    Abstract: A synthetic quartz glass for optical use, to be used by irradiation with light within a range of from the ultraviolet region to the vacuum ultraviolet region, which contains fluorine, which has a ratio of the scattering peak intensity of 2250 cm?1 (I2250) to the scattering peak intensity of 800 cm?1 (I800), i.e. I2250/I800, of at most 1×10?4 in the laser Raman spectrum, and which has an absorption coefficient of light of 245 nm of at most 2×10?3 cm?1.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: April 4, 2006
    Assignee: Asahi Glass Company, Limited
    Inventors: Yoshiaki Ikuta, Shinya Kikugawa, Noriaki Shimodaira, Akio Masui, Shuhei Yoshizawa
  • Patent number: 7003985
    Abstract: In accordance with the invention, the polymeric coating is removed from a coated optical fiber by disposing the fiber within a non-oxidizing environment and applying sufficient heat to volatilize at least a portion of the polymeric coating. The result is that the coating material bursts from the fiber, yielding a clean glass surface virtually free of surface flaws. In a preferred embodiment the non-oxidizing environment is inert gas and the heat is provided by resistive filament heaters.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: February 28, 2006
    Inventors: Robert F. Swain, Andrew D. Yablon
  • Patent number: 6935139
    Abstract: The method of manufacturing an optical fiber in accordance with the present invention comprises a step of yielding an optical fiber by drawing an optical fiber preform softened upon heating, wherein a temperature at which the optical fiber preform is softened is at least 1800° C., whereas the optical fiber preform or optical fiber has a glass cooling rate of 4000° C./sec or less when attaining a temperature of 1800° C.
    Type: Grant
    Filed: May 14, 2002
    Date of Patent: August 30, 2005
    Assignee: Sumitomo Electric Industries
    Inventors: Katsuya Nagayama, Kazuya Kuwahara, Takayuki Shimazu
  • Patent number: 6928840
    Abstract: A drawing apparatus 1 comprises a drawing furnace 11, a protecting tube 21, and a resin curing unit 31. A buffer chamber 41 is disposed between the drawing furnace 11 and the protecting tube 21, and has a length L1 in the drawing direction of the optical fiber 3. The buffer chamber 41 is constituted by a first buffer cell 42 and a second buffer cell 45. In the space within the buffer chamber 41, an He gas, which is an atmosphere gas within the drawing furnace 11, and the air, which is an atmosphere gas within the protecting tube 21, exist in a mixed state. The optical fiber 3 drawn upon heating in the drawing furnace 11 is fed to the protecting tube 21, and a predetermined part of the optical fiber 3 is annealed at a predetermined cooling rate. Thereafter, a coating die 62 coats the optical fiber 3 with a UV resin solution 63, and the resin curing unit 31 cures the UV resin 63, whereby a coated optical fiber 4 is obtained.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: August 16, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Katsuya Nagayama, Yuichi Ohga, Kazuya Kuwahara, Ichiro Tsuchiya
  • Patent number: 6907757
    Abstract: The drawing method of the present invention uses a drawing furnace comprising a furnace muffle tube, a furnace body and a heater. According to the method, an optical fiber preform is inserted from the inlet of the furnace muffle tube, the optical fiber preform is melted by means of a heater, under a specified gas atmosphere, and is drawn toward the outlet of the furnace muffle tube by means of a specified drawing tension. The optical fiber preform and the drawing furnace used in this method both satisfy the condition of below-indicated formula (1): L/D?8??(1) wherein L indicates the length of the furnace body in the drawing direction and D indicates the diameter of the optical fiber preform.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: June 21, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuya Kuwahara, Katsuya Nagayama, Ichiro Tsuchiya, Masashi Onishi
  • Patent number: 6904772
    Abstract: Optical waveguide fiber having low water peak as well as optical waveguide fiber preforms and methods of making optical waveguide fiber preforms from which low water peak and/or low hydrogen aged attenuation optical waveguide fibers are formed, including optical waveguide fiber and preforms made via OVD. The fibers may be hydrogen resistant, i.e. exhibit low hydrogen aged attenuation. A low water peak, hydrogen resistant optical waveguide fiber is disclosed which exhibits an optical attenuation at a wavelength of about 1383 nm which is less than or equal to an optical attenuation exhibited at a wavelength of about 1310 nm.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: June 14, 2005
    Assignee: Corning Incorporated
    Inventors: George E. Berkey, Dana C. Bookbinder, Richard M. Fiacco, Dale R. Powers
  • Patent number: 6851282
    Abstract: A drawing apparatus 1 has a drawing furnace 11, a heating furnace 21, and a resin curing section 31. The drawing furnace 11 has a muffle tube 13 to which an He gas supply passage 15 from an He gas supply section 14 is connected so as to supply He gas. The optical fiber 3 drawn upon heating by the drawing furnace 11 is fed to the heating furnace 21, whereby a predetermined part of the optical fiber 3 is annealed at a predetermined cooling rate. The heating furnace 21 has a muffle tube 23 to which an N2 gas supply passage 25 from an N2 gas supply section 24 is connected so as to supply N2 gas. Thereafter, the optical fiber 3 is coated with a UV resin 39 by a coating die 38, and the UV resin 39 is cured in the resin curing section 31, whereby a coated optical fiber 4 is formed.
    Type: Grant
    Filed: November 26, 2001
    Date of Patent: February 8, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Katsuya Nagayama, Yuichi Ohga, Tatsuhiko Saitoh, Hiroshi Takamizawa
  • Patent number: 6845636
    Abstract: A dehydration and consolidation furnace and a dehydration and consolidation method in which gas in a chamber does not leak to a furnace body room and gas in a furnace body room does not leak into a chamber is provided. A furnace of one embodiment of this invention has first muffle tube 3 and second muffle tube 4. The second muffle tube 4 is arranged coaxially around the first muffle tube 3. An optical fiber preform is arranged in this furnace. During the dehydration and consolidation process the pressure of the intermediate room 10 is set lower than a pressure inside the first muffle tube and outside the second muffle tube, and a gas supply and exhaust of the intermediate room 10 are performed independent of the gas supply and exhaust of the first muffle tube and a furnace body room.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: January 25, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Yamazaki, Takashi Kogo, Yuichi Ohga, Tadashi Enomoto
  • Patent number: 6813908
    Abstract: The invention includes inventive methods of treating a soot preform. One method includes heating a soot preform to a temperature of less than about 1000° C. and exposing the preform to a substantially halide free reducing agent. Preferred reducing agents include carbon monoxide and sulfur dioxide. Another inventive method of treating the preform includes exposing the preform, in a furnace, to a substantially non-chlorine containing atmosphere comprising carbon monoxide. The preform is heated to a temperature of at least about 1000° C. Preferably this method is incorporated into the process for making an optical fiber. An additional method of treating the preform includes doping the preform with fluorine and exposing the fluorine doped preform to a substantially chlorine free atmosphere comprising at least carbon monoxide at a temperature of at least 1100° C., thereby reacting excess oxygen present in the furnace.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: November 9, 2004
    Assignee: Corning Incorporated
    Inventors: Kintu O. Early, Claude E. Lacy, Susan L. Schiefelbein, Sabyasachi Sen, Wanda J. Walczak, Joseph M. Whalen, Tiffany L. James, Hazel B. Matthews, Chukwuemeka B. Onuh
  • Patent number: 6776012
    Abstract: Embodiments of the invention include a method for making optical fiber having reduced aging or hydrogen aging loss over the life of the fiber and optical fiber systems including such optical fibers. The method includes the steps of dehydrating an optical fiber glass core rod in a first environment including oxygen and at least one of chlorine-containing gases, fluorine-containing gases and carbon monoxide; and adjusting the oxygen stoichiometry of the first environment so that it is neither oxygen-rich nor oxygen-deficient. Improved silicon-oxygen stoichiometry during one or more preform manufacturing steps reduces the amount of Si defects generated in the optical fiber preform. Also, deuterium exposure of optical fiber drawn from the preform reduces the likelihood of having atomic defects such as Si defects in the optical fiber that, over time, attract and bond with hydrogen atoms to form molecules that contribute to increased water absorption loss.
    Type: Grant
    Filed: June 26, 2001
    Date of Patent: August 17, 2004
    Assignee: Fitel USA Corp.
    Inventors: Kai H Chang, David Kalish, Thomas John Miller
  • Publication number: 20040139766
    Abstract: Systems and methods for treating spools of fiber using recycled gas. Spools of fiber are placed in chambers which can be sealed for exposure to the treatment gas. When a chamber is closed and sealed the treatment gas is pumped into the chamber to a specified pressure temperature and pressure to react with the fiber. Upon completion of the reaction the gas is pumped from the chamber in order to facilitate the removal of the treated fiber. The gas can be evacuated with a vacuum pump and compressed to be stored in a pressure vessel for reuse. At this time the gas may be analyzed. If the concentration of a component is too low, the gas may be vented or it may be enriched so that it may be recycled; otherwise it is compressed for storage and the process is repeated.
    Type: Application
    Filed: January 17, 2003
    Publication date: July 22, 2004
    Inventors: Gene K. Weeks, Junjun Wu, Ramdane Assas, Kai H. Chang, Siu-Ping Hong
  • Publication number: 20040139765
    Abstract: A method of producing with the collapsing process an optical fiber preform capable of forming an optical fiber in which an increment in transmission loss due to OH absorption is reduced, and an optical fiber preform and an optical fiber produced with the method. The method comprises reducing the amount of hydrogen atom-containing substances in a glass pipe, sealing one end of the glass pipe, and collapsing the glass pipe to obtain a solid body. One aspect of the method comprises heating the glass pipe at 550° C. or below, sealing one end of the glass pipe, and collapsing the glass pipe to obtain a solid body. The preform produced with the method has a feature in that its portion formed by the interface portion at the time of the collapsing contains OH groups at a concentration of 100 wt. ppb or below. The optical fiber produced by drawing the preform has a feature in that its OH-originated loss is less than 0.5 dB/km at a wavelength of 1.38 &mgr;m.
    Type: Application
    Filed: January 5, 2004
    Publication date: July 22, 2004
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masaaki Hirano, Tomomi Moriya, Hideyuki Ijiri, Shinji Hasegawa, Takashi Sasaki, Toshiki Taru
  • Publication number: 20040121247
    Abstract: The present invention is a method of making a lithography photomask and photomask blank. The method of making the lithography photomask and photomask blank includes providing a silicon oxyfluoride glass tube having an OH content less than 50 ppm. The method further includes cutting the silicon oxyfluoride glass tube, flattening the silicon oxyfluoride glass tube, and forming the flattened cut silicon oxyfluoride glass tube into a photomask blank having a planar surface. The present invention includes a glass lithography mask preform. The glass lithography mask preform is a longitudinal silicon oxyfluoride glass tube that has an OH content≦10 ppm, a F wt. % concentration≧0.5 wt. %.
    Type: Application
    Filed: December 10, 2003
    Publication date: June 24, 2004
    Inventors: George Edward Berkey, Lisa Anne Moore, Michelle Diane Pierson
  • Patent number: 6748767
    Abstract: Fiber is drawn from a preform comprising a silica body, e.g., a sol-gel derived overcladding or substrate tube. Prior to sintering, the body is treated with a gaseous mixture containing one or more non-oxygenated sulfur halides, to remove and/or reduce the size of refractory oxide particles, and/or dehydroxylate the body. Removal of metal oxide particles or reduction in their size contributes to drawing of optical fiber exhibiting desirable strength, since such particles act as initiation sites for breakage. Advantageously, the halides include sulfur chlorides, which provide desirable improvements compared to treatment by oxygenated sulfur chlorides such as thionyl chloride (SOCl2).
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: June 15, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mary Louise Mandich, William David Reents, Jr.