Patents by Inventor Hiroo Kanamori
Hiroo Kanamori has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5320658Abstract: There is provided a process of melt drawing an optical fiber from a preform therefor in which a heating furnace comprising a muffle tube inside thereof through which the optical fiber is passed is provided immediately below a melt drawing furnace to further draw the optical fiber while heated, and an interior of the muffle tube is kept in an atmosphere selected from the group consisting of an inert atmosphere, an atmosphere comprising oxygen gas and an atmosphere comprising hydrogen gas.Type: GrantFiled: August 3, 1992Date of Patent: June 14, 1994Assignee: Sumitomo Electric Industries, Ltd.Inventors: Yuichi Ohga, Shinji Ishikawa, Hiroo Kanamori, Ichiro Yoshimura, Horoshi Yokota
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Patent number: 5306322Abstract: The present invention providesa process for the dehydrating and purifying treatment by heating a porous glass preform for an optical fiber comprising passing the porous glass preform through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere comprising an inert gas and a silicon halogenide gas;a process for the fluorine-doping treatment by heating a porous glass preform for an optical fiber comprising passing a porous glass preform through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere comprising a fluorine compound gas and an inert gas; anda process for the vitrifying treatment by heating a porous glass preform for an optical fiber comprising passing the preform, which has been previously dehydrated and purified, through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere gas.Type: GrantFiled: July 24, 1992Date of Patent: April 26, 1994Assignee: Sumitomo Electric Industries, Ltd.Inventors: Shinji Ishikawa, Yuichi Ohga, Ichiro Tsuchiya, Hiroo Kanamori, Hiroshi Yokota, Michihisa Kyoto
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Patent number: 5259856Abstract: A heating furnace for heating a porous preform made of fine particles of quartz base glass for an optical fiber which comprises a heater and a muffle tube positioned inside the heater to separate a heating atmosphere from the heater, wherein the muffle tube body consists of highly pure carbon and an inner wall and an outer wall of the body is coated with a carbon material selected from the group consisting of pyrolytic graphite and solid-phase carbonized glassy carbon.Type: GrantFiled: June 1, 1992Date of Patent: November 9, 1993Assignee: Sumitomo Electric Industrial, Ltd.Inventors: Yuichi Ohga, Shinji Ishikawa, Hiroo Kanamori, Ichiro Tsuchiya, Hiroshi Yokota
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Patent number: 5244846Abstract: An optical functioning glass for enabling optical amplification at 1.3-.mu.m wavelength band or increasing efficiency of the amplification is disclosed. The optical functioning glass contains Nd.sup.3+ as an active material and uranium, both of which are doped in a multi-component function glass serving as a host glass. Since uranium is doped in the optical functioning glass, light emission of Nd.sup.3+ in the 1.06-.mu.m wavelength band can be absorbed by uranium. A decrease in efficiency of induced emission in a 1.3-.mu.m wavelength band can be prevented, and an optical functioning glass suitable for optical amplification in the 1.3-.mu.m wavelength band can be obtained. When a fiber is formed using the optical functioning glass as a core, a low-threshold, high-gain fiber amplifier, fiber laser, and the like can be obtained.Type: GrantFiled: February 3, 1992Date of Patent: September 14, 1993Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corp.Inventors: Masashi Onishi, Koji Nakazato, Hiroo Kanamori, Minoru Watanabe, Yoshiaki Miyajima
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Patent number: 5243677Abstract: A quartz optical waveguide comprising a substrate, a ridge-form core part formed on said substrate and a part which surrounds said core part and has a lower refractive index than that of said core part, wherein a refractive index changes continuously at an interface between said core part and said part having the lower refractive index, which has a decreased transmission loss and a connection loss when connected with an optical fiber.Type: GrantFiled: July 10, 1992Date of Patent: September 7, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroo Kanamori, Masumi Ito, Shinji Ishikawa, Haruhiko Aikawa, Sumio Hoshino
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Patent number: 5238479Abstract: The invention is a method for producing a porous preform for use in the fabrication of an optical fiber at least two burners synthesize glass soot particles, one of which generates a double-layer flame and one of which is used for forming a core part of the preform. The method comprises the steps of supplying SiCl.sub.4 and optionally GeCl.sub.4 to the inner flame of the double-layer flame, and only SiCl.sub.4 to an outer flame of the double-layer flame to flame hydrolyze the supplied compounds and synthesize glass soot particles. Compounds SiCl.sub.4 and GeCl.sub.4 as glass-forming raw materials are supplied to the burner for forming the core part of the preform by depositing the generated glass soot particles on the lower end of a rotating starting member. The generated porous preform comprises a core part containing at least partly GeO.sub.2, and a surface having a low concentration of GeO.sub.2 which reduces cracking or peeling.Type: GrantFiled: December 4, 1992Date of Patent: August 24, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Yuichi Ohga, Toshio Danzuka, Hiroo Kanamori, Hiroshi Yokota
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Patent number: 5224185Abstract: An optical switch with improved stability which has a flat waveguide including at least two optical waveguides which are made of a glass containing silica and arranged closely each other, at least a core part of each of the optical waveguides consisting of an amorphous material which is prepared by a sol-gel method and contains organic molecules doped and orientated in a direction of electrostatic field by the application of an electrostatic field, and means for changing an optical path through change of a refractive index of the core part by applying an external force to the core part, which means is provided near the core part.Type: GrantFiled: February 21, 1992Date of Patent: June 29, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Masumi Ito, Sumio Hoshino, Hiroo Kanamori
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Patent number: 5221309Abstract: A method for producing a glass preform, which method comprises forming a soot preform of glass fine particles comprising SiO.sub.2 by flame hydrolysis or solution hydrolysis of a starting glass material and sintering the soot preform in an atmosphere containing at least SiF.sub.4 to obtain a glass preform which is free from an increase in absorption due to impurities and has sufficiently low attenuation of light transmission.Type: GrantFiled: August 31, 1992Date of Patent: June 22, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Michihisa Kyoto, Minoru Watanabe, Hiroo Kanamori
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Patent number: 5221307Abstract: A preform for a polarization retaining optical fiber is produced by making at least two bores symmetrically around a center axis of a preform comprising a core part and a cladding part which surrounds the core part, decreasing a diameter of one end of each bore, or connecting a glass tube to one end of the preform, the glass tube having a part with a smaller inner diameter near its end which is connected to the preform, inserting a first glass rod, a stressing member and a second glass rod in this order from the other end of each bore or from an end of each bore which is remote from the connected glass tube, contacting the first glass rod to the diameter-decreased end of each bore or to the part with a smaller inner diameter of the glass tube, and heating and fusing the second glass rod to the preform.Type: GrantFiled: June 3, 1992Date of Patent: June 22, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Masahiro Takagi, Hiroshi Suganuma, Hiroo Kanamori
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Patent number: 5217516Abstract: A refractive index profile in a glass article is easily controlled by heating a solid or hollow cylindrical glass soot preform in an atmosphere comprising a fluorine-containing compound under such conditions that a partial pressure of the fluorine-containing compound is changed as the heating proceeds so as to control a fluorine concentration in a radial direction of the optical glass article.Type: GrantFiled: March 29, 1991Date of Patent: June 8, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Yoichi Ishiguro, Hiroo Kanamori, Akira Urano, Michihisa Kyoto
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Patent number: 5211730Abstract: Redeposition of glass particles is prevented by a method for heating a glass body comprising heating a part of the glass body with relatively moving the glass body and a heating source, wherein an inert gas is blown from inert gas-blowing means onto a surface of the glass body near a heated part of the glass body.Type: GrantFiled: July 7, 1992Date of Patent: May 18, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroo Kanamori, Manzo Yamaguchi, Hikaru Satoh
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Patent number: 5202947Abstract: There is disclosed an optical component capable of amolifying function by itself and a method of producing thereof. The component includes a light amplifying portion therein and the light amplifying portion includes active elements which serves the light amplification. In the producing method, the amplifying portion is, for example, formed by utilizing sol-gel method to introduce the active elements.Type: GrantFiled: November 29, 1991Date of Patent: April 13, 1993Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone CorporationInventors: Sumio Hoshino, Masumi Ito, Masayuki Shigematsu, Hiroo Kanamori, Hisasi Izumita
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Patent number: 5193137Abstract: A quartz optical waveguide comprising a support, a quartz glass core part formed on said support and a part which surrounds said core part and has a lower refractive index than that of said core part, wherein said core part and/or a part of said lower refractive index part through which light is guided have a functional material waveguide film containing a functional material, which has a function such as laser amplification or a linear optical effect.Type: GrantFiled: September 25, 1991Date of Patent: March 9, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Sumio Hoshino, Hiroo Kanamori, Masumi Ito, Shinji Ishikawa, Haruhiko Aikawa
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Patent number: 5179614Abstract: A quartz optical waveguide comprising a substrate, a ridge-form core part formed on said substrate and a part which surrounds said core part and has a lower refractive index than that of said core part, wherein a refractive index changes continuously at an interface between said core part and said part having the lower refractive index, which has a decreased transmission loss and a connection loss when connected with an optical fiber.Type: GrantFiled: September 20, 1991Date of Patent: January 12, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroo Kanamori, Masumi Ito, Shinji Ishikawa, Haruhiko Aikawa, Sumio Hoshino
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Patent number: 5163987Abstract: A method for producing a glass preform for use in the fabrication of an optical fiber, which comprises adding fluorine to a soot preform in an atmosphere comprising a fluorine-coating compound at a temperature at which the soot preform is in the porous state and then keeping or inserting it in an atmosphere containing a fluorine-containing compound at a higher temperature to vitrify it to form a glass preform, from which glass preform, an optical fiber homogeneously containing fluorine is fabricated.Type: GrantFiled: March 6, 1992Date of Patent: November 17, 1992Assignee: Sumitomo Electric Industries, Ltd.Inventors: Yoichi Ishiguro, Michihisa Kyoto, Hiroo Kanamori
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Patent number: 5160522Abstract: A preform for a polarization retaining optical fiber is produced by making at least two bores symmetrically around a center axis of a preform comprising a core part and a cladding part which surrounds the core part, decreasing a diameter of one end of each bore, or connecting a glass tube to one end of the preform, the glass tube having a part with a smaller inner diameter near its end which is connected to the preform, inserting a first glass rod, a stressing member and a second glass rod in this order from the other end of each bore or from an end of each bore which is remote from the connected glass tube, contacting the first glass rod to the diameter-decreased end of each bore or to the part with a smaller inner diameter of the glass tube, and heating and fusing the second glass rod to the preform.Type: GrantFiled: August 6, 1991Date of Patent: November 3, 1992Assignee: Sumitomo Electric Industries, Ltd.Inventors: Masahiro Takagi, Hiroshi Suganuma, Hiroo Kanamori
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Patent number: 5106401Abstract: The present invention providesa process for the dehydrating and purifying treatment by heating a porous glass preform for an optical fiber by passing the porous glass preform through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere containing an inert gas and a silicon halogenide gas;a process for the fluorine-doping treatment by heating a porous glass preform for an optical fiber by passing a porous glass preform through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere containing a fluorine compound gas and an inert gas; anda process for the vitrifying treatment by heating a porous glass preform for an opticla fiber by passing the preform, which has been previously dehydrated and purified, through a muffle tube having a SiC layer at least on its inner surface at a high temperature under an atmosphere gas.Type: GrantFiled: June 28, 1990Date of Patent: April 21, 1992Assignee: Sumitomo Electric Industries, Ltd.Inventors: Shinji Ishikawa, Yuichi Ohga, Ichiro Tsuchiya, Hiroo Kanamori, Hiroshi Yokota, Michihisa Kyoto
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Patent number: 5055121Abstract: An optical fiberglass preform having fluorine selectively added to its cladding is produced by:depositing soot of quartz glass on a pipe from starting member by using burners for synthesizing glass soot to form a porous glass preform consisting of a core porous glass body a peripheral portion of which has a larger bulk density than the other portion and a cladding porous glass body,heating said porous glass preform in a dehydration atmosphere while supplying dehydration gas through the pipe form starting member andheating and vitrifying the dehydrated porous glass preform in an atmosphere containing a fluorine-containing compound.Type: GrantFiled: July 27, 1990Date of Patent: October 8, 1991Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroo Kanamori, Yoichi Ishiguro, Gotaro Tanaka
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Patent number: 5032079Abstract: There is provided a heating furnace comprising a furnace body, a cylindrical zone heater in the furnace body, a muffle tube installed through the furnace body for thermally treating a porous preform made of high purity quartz glass by moving the preform vertically therethrough and a partition means in the portion of the muffle tube projecting above the furnace body to divide an interior space of the muffle tube into an upper space and a lower one.Type: GrantFiled: December 29, 1989Date of Patent: July 16, 1991Assignee: Sumitomo Electric Industries, Ltd.Inventors: Ichiro Tsuchiya, Shinji Ishikawa, Masahide Saitoh, Yoichi Ishiguro, Hiroo Kanamori
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Patent number: 5022904Abstract: A refractive index profile in a glass article is easily controlled by heating a solid or hollow cylindrical glass soot preform in an atmosphere comprising a fluorine-containing compound under such conditions that a partial pressure of the fluorine-containing compound is changed as the heating proceeds so as to control a fluorine concentration in a radial direction of the optical glass article.Type: GrantFiled: June 13, 1990Date of Patent: June 11, 1991Assignee: Sumitomo Electric Industries, Ltd.Inventors: Yoichi Ishiguro, Hiroo Kanamori, Akira Urano, Michihisa Kyoto