Patents by Inventor Tomohiko Ueda

Tomohiko Ueda 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).

  • Publication number: 20050238308
    Abstract: An optical fiber suitable for use in a single fiber or multifiber optical connector or array is structured with a core region and a cladding region surrounding the core region, and exhibits a bending loss of a fundamental mode of the fiber at a wavelength ? is lower than 0.1 dB/m at a diameter of 15 mm, a mode-field diameter of the fundamental mode at an end of the fiber at the wavelength ? is between 8.0 ?m and 50 ?, and a bending loss of a first higher-order mode at the wavelength ? is higher than 1 dB/m at a diameter of 30 mm. The fiber may be multistructured, wherein the cladding region comprises a main medium and a plurality of sub medium regions therein to form a spatially uniform average refractive index.
    Type: Application
    Filed: March 15, 2005
    Publication date: October 27, 2005
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Takemi Hasegawa, Eisuke Sasaoka, Daizo Nishioka, Tomohiko Ueda, Toshifumi Hosoya
  • Publication number: 20050123248
    Abstract: An optical connector ferrule molding die 1 for molding an optical connector ferrule having a plurality of optical fiber holes comprises an upper die 10, a lower die 11, and an intermediate die 12, whereas the intermediate die 12 comprises a plurality of optical fiber hole forming pins 126 for forming optical fiber holes. The lower die 11 is provided with a protrusion 114 for forming a window hole of the optical connector ferrule, whereas the optical fiber hole forming pins 126 projecting from the intermediate die 12 are secured by through holes 115 penetrating through the protrusion 114 and V-grooves 113.
    Type: Application
    Filed: November 29, 2002
    Publication date: June 9, 2005
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD
    Inventors: Wataru Sakurai, Hiroshi Katsura, Toshiaki Kaki, Kei Sunaga, Tomohiko Ueda, Toshifumi Hosoya, Daizo Nishioka, Kenichiro Ohtsuka, Yuko Masunaga
  • Patent number: 6901197
    Abstract: An optical fiber suitable for use in a single fiber or multifiber optical connector or array is structured with a core region and a cladding region surrounding the core region, and exhibits a bending loss of a fundamental mode of the fiber at a wavelength ? is lower than 0.1 dB/m at a diameter of 15 mm, a mode-field diameter of the fundamental mode at an end of the fiber at the wavelength ? is between 8.0 ?m and 50 ?, and a bending loss of a first higher-order mode at the wavelength ? is higher than 1 dB/m at a diameter of 30 mm. The fiber may be multistructured, wherein the cladding region comprises a main medium and a plurality of sub medium regions therein to form a spatially uniform average refractive index.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: May 31, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takemi Hasegawa, Eisuke Sasaoka, Daizo Nishioka, Tomohiko Ueda, Toshifumi Hosoya
  • Publication number: 20040151439
    Abstract: An optical connector according to the present invention has a ferrule body provided with a fiber positioning hole, a pair of guide holes into which guide pins are inserted, and a connecting end face in which ends of the fiber positioning hole and guide holes open. A chamfer portion equivalent to a part of a surface of a body of revolution is formed at each guide hole on the connecting end face side. Further, the connecting end face is formed at an angle relative to a plane normal to the center axes of the pair of guide holes. In this structure, the slope of the connecting end face can suppress degradation of connection loss, and the provision of the chamfer portions can facilitate insertion of the guide pins, prevent damage of the connecting end face due to the guide pins, and also suppress degradation of connection loss due to the damage.
    Type: Application
    Filed: January 12, 2004
    Publication date: August 5, 2004
    Inventors: Kenichiro Ohtsuka, Hiroshi Katsura, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6676300
    Abstract: A ferrule for optical connector according to the present invention is provided with a fiber positioning hole, a pair of guide holes into which guide pins are inserted, and a connecting end face in which ends of the fiber positioning hole and guide holes open. A chamfer portion equivalent to a part of a surface of a body of revolution is formed at each guide hole on the connecting end face side. Further, the connecting end face is formed at an angle relative to a plane normal to the center axes of the pair of guide holes. In this structure, the slope of the connecting end face can suppress degradation of connection loss, and the provision of the chamfer portions can facilitate insertion of the guide pins, prevent damage of the connecting end face due to the guide pins, and also suppress degradation of connection loss due to the damage.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: January 13, 2004
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Hiroshi Katsura, Tomohiko Ueda, Toshiaki Kakii
  • Publication number: 20030161584
    Abstract: A pair of guide holes for guide pin insertion and one or a plurality of optical fiber positioning holes extending inwardly from the front end surface are formed in a connector ferrule of an optical connector. A chamfer is formed on the opening edge portion of the guide hole of the connector ferrule on the front end surface side thereof. The opening diameter R of the guide hole at the front end surface is preferably 1.0 to 1.5 mm when the front end surface is slant polished at an angle of 8 degrees. Furthermore, the chamfering angle &thgr; of the chamfer is preferably 90 to 150 degrees. Moreover, the average particle size of the filler contained in the connector ferrule is no more than 20 &mgr;m. As a result, the surface of the chamfer is comparatively smooth.
    Type: Application
    Filed: February 28, 2002
    Publication date: August 28, 2003
    Inventors: Kenichiro Ohtsuka, Yoshikyo Tamekuni, Hiroshi Katsura, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6565265
    Abstract: An optical connector comprising a ferrule including an optical fiber, wherein a hollow portion for optical fiber protrusion is formed on a front end face of the ferrule, the optical fiber is inserted into an optical fiber positioning hole extended from an optical fiber protrusion port provided on a bottom face of the hollow portion toward an inside of the ferrule, and a tip face of the optical fiber is drawn in the hollow portion. This makes it possible to provide an optical connector which can shorten a time for assembly and can be assembled easily and inexpensively.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: May 20, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Takahisa Yamaguchi, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6530696
    Abstract: An optical connector includes a ferrule and a pair of guide pins. Fiber insertion holes and a pair of pin insertion holes are formed in the ferrule. Each of the pair of guide pins has a total length larger than that of each pin insertion hole. The guide pins are coupled to each other on one end portion thereof. The other ends of the guide pins can be accommodated in the pin insertion holes by sliding the guide pins. An optical connecting surface of the ferrule is located at the extreme tip portion when viewed from the optical axis direction of an optical fiber while the other ends of the pair of guide pins are accommodated in the pin insertion holes. This makes it possible to bring the optical connecting surface of the ferrule into contact with an opposite-side optical component while the other ends of the guide pins are accommodated in the pin insertion holes and prohibited from protruding from the optical connecting surface.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: March 11, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tomohiko Ueda, Toshiaki Kakii
  • Publication number: 20020154867
    Abstract: A ferrule for optical connector according to the present invention is provided with a fiber positioning hole, a pair of guide holes into which guide pins are inserted, and a connecting end face in which ends of the fiber positioning hole and guide holes open. A chamfer portion equivalent to a part of a surface of a body of revolution is formed at each guide hole on the connecting end face side. Further, the connecting end face is formed at an angle relative to a plane normal to the center axes of the pair of guide holes. In this structure, the slope of the connecting end face can suppress degradation of connection loss, and the provision of the chamfer portions can facilitate insertion of the guide pins, prevent damage of the connecting end face due to the guide pins, and also suppress degradation of connection loss due to the damage.
    Type: Application
    Filed: February 28, 2002
    Publication date: October 24, 2002
    Inventors: Kenichiro Ohtsuka, Hiroshi Katsura, Tomohiko Ueda, Toshiaki Kakii
  • Publication number: 20020102068
    Abstract: A ferrule for optical connector according to the present invention is provided with a fiber positioning hole, a pair of guide holes into which guide pins are inserted, and a connecting end face in which ends of the fiber positioning hole and guide holes open. A chamfer portion equivalent to a part of a surface of a body of revolution is formed at each guide hole on the connecting end face side. Further, the connecting end face is formed at an angle relative to a plane normal to the center axes of the pair of guide holes. In this structure, the slope of the connecting end face can suppress degradation of connection loss, and the provision of the chamfer portions can facilitate insertion of the guide pins, prevent damage of the connecting end face due to the guide pins, and also suppress degradation of connection loss due to the damage.
    Type: Application
    Filed: January 25, 2002
    Publication date: August 1, 2002
    Inventors: Kenichiro Ohtsuka, Hiroshi Katsura, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6409394
    Abstract: In an optical connector for securing an optical fiber by inserting it into an optical fiber positioning hole of a connector ferrule body, an end face of the optical fiber is disposed within the optical fiber positioning hole, a predetermined length region of the optical fiber on the end face side is in a free state adapted to expand and contract, and the end face of the optical fiber is buried in a refractive index matching material filling near an opening portion of the optical fiber positioning hole.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: June 25, 2002
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tomohiko Ueda, Kenichiro Ohtsuka, Toshiaki Kakii
  • Patent number: 6377743
    Abstract: An optical fiber holder 1B is an optical fiber holder for holding a plurality of optical fibers in line, and includes a base member 20 with a plurality of parallel positioning grooves 90 for positioning and aligning the plurality of optical fibers, and a lid member 32 adapted to cover the plurality of positioning grooves 90 and to fix the plurality of optical fibers, arranged in the positioning grooves 90, by pressing against the bottom portions of the positioning grooves 90. The lid member 32 has small projections 102 on its portion which comes into contact with the optical fibers.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: April 23, 2002
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tomohiko Ueda, Kenichiro Ohtsuka, Toshiaki Kakii
  • Patent number: 6331081
    Abstract: An optical transmission component and a method of making the same in which one or a plurality of optical fibers 1 are fixed to a main body 3 of the optical transmission component with one end face of each optical fiber being exposed, and thus exposed end face is used as a connecting end face to be optically connected to another optical transmission component. The coating 1b of each optical fiber 1 is removed, so as to expose a predetermined length of an optical fiber 1a. An end face 1c of thus exposed optical fiber is processed by spark discharge processing in a short period of time, such that at least the front end of a core portion projects from the front end of its cladding portion. Thus processed optical fiber 1 is inserted into the main body and fixed thereto with an adhesive 5, while a predetermined pressure is being added along the optical axis of each optical fiber 1 from the end face 1c side.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: December 18, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii
  • Publication number: 20010036341
    Abstract: An optical connector comprising a ferrule including an optical fiber, wherein a hollow portion for optical fiber protrusion is formed on a front end face of the ferrule, the optical fiber is inserted into an optical fiber positioning hole extended from an optical fiber protrusion port provided on a bottom face of the hollow portion toward an inside of the ferrule, and a tip face of the optical fiber is drawn in the hollow portion. This makes it possible to provide an optical connector which can shorten a time for assembly and can be assembled easily and inexpensively.
    Type: Application
    Filed: March 5, 2001
    Publication date: November 1, 2001
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kenichiro Ohtsuka, Takahisa Yamaguchi, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6293708
    Abstract: An optical connector includes a first ferrule which holds the ends of a first optical fiber unit including at least one optical fiber, and a housing. The housing is a U-shaped member with parallel arms extending in the lengthwise direction of the first optical fiber unit. The housing surrounds one of the widthwise sides of the first ferrule from which the first optical fiber unit is derived and the lengthwise sides of the first ferrule, whereby the housing accommodates the first ferrule. The housing receives a second ferrule which holds the ends of a second optical fiber unit including at least one optical fiber through the U-shaped opening. The housing surrounds the lengthwise side of the second ferrule and a part of the side of the second ferrule from which the second optical fiber unit is derived, whereby the first and second ferrules are coupled together.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: September 25, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6264375
    Abstract: A fiber optic connector ferrule in which a coating-accommodating portion for mounting a coated portion of an optical fiber and maintaining the optical fiber such that the axis thereof becomes substantially straight from the mounted portion to the front end is formed behind a fiber-arranging hole by the steps of: disposing one or a plurality of mold pins each having a columnar portion formed on a distal end side thereof and a prismatic portion, disposed on a proximal end side thereof, having substantially a quadrangular cross section, with side faces of the prismatic portions being in contact with each other, within a mold such that each mold pin is slidable in an axial direction of the columnar and prismatic portions; and filling the mold with a resin, and axially pulling off each mold pin after the resin is cured, thereby causing the columnar portion to form the fiber-arranging hole and causing the prismatic portion to form the coating-accommodating portion for mounting the coated portion.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: July 24, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6196732
    Abstract: The ferrule 7 of the optical connector in accordance with the present invention has an optical fiber inserting portion 11 extending inward from an optical connection opening 10 formed in the nose surface 9, thereby projecting the end portion of an optical fiber 8 from the optical connection opening 10 in the nose surface 9. The nose surface 9 has a first flat portion 15 and a second flat portion 14. The second flat portion 14 extends while including the optical connection opening 10 therein. The first flat portion 15 extends so as to project ahead of the second flat portion 14.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: March 6, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yoshikyo Tamekuni, Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6193421
    Abstract: A short optical fiber 2 is incorporated in a ferrule 1 having a polished front end, so as to be projected from the rear end of the ferrule. In a base member 3 in which the short optical fiber is to be fitted into a hole 3b, a V-groove 3d to which the glass portion of an optical fiber is to be fixed, and a V-groove 3e to which the coated portion is to be fixed are formed. A cover member 4 is placed on the base member. The base member 3 and the cover member 4 are clamped by clamp members 5a and 5b and the base member 3 presses to V-grooves. Wedges which are not shown are pressingly inserted between recessed 3g and 4c, and 3h and 4d, and an optical fiber 10 is inserted from the rear portion. Thereafter, the wedges are detached and the optical connector is attached to the terminal of the optical fiber 10.
    Type: Grant
    Filed: August 25, 1999
    Date of Patent: February 27, 2001
    Assignees: Sumitomo Electric Industries, Ltd, Nippon Telegraph and Telephone Corporation
    Inventors: Yoshikyo Tamekuni, Tomohiko Ueda, Kazuo Hogari, Shin-ichi Furukawa
  • Patent number: 6095695
    Abstract: An optical connector includes a first ferrule which holds the ends of a first optical fiber unit including at least one optical fiber, and a housing. The housing is a U-shaped member with parallel arms extending in the lengthwise direction of the first optical fiber unit. The housing surrounds one of the widthwise sides of the first ferrule from which the first optical fiber unit is derived and the lengthwise sides of the first ferrule, whereby the housing accommodates the first ferrule. The housing receives a second ferrule which holds the ends of a second optical fiber unit including at least one optical fiber through the U-shaped opening. The housing surrounds the lengthwise side of the second ferrule and a part of the side of the second ferrule from which the second optical fiber unit is derived, whereby the first and second ferrules are coupled together.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: August 1, 2000
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii
  • Patent number: 6062740
    Abstract: An optical connector in which an optical fiber is fixed within a ferrule such that a tip of the optical fiber is disposed at a front end face position of the ferrule. An optical-fiber-positioning hole formed so as to directly extend into the ferrule from an optical connecting orifice formed in the front end face of the ferrule has a diameter greater than a diameter of the optical fiber positioned within the optical-fiber-positioning hole, the optical-fiber-positioning hole having therein a compressible unfixing area for allowing the optical fiber to compress along the optical-fiber-positioning hole, and a fixing area, disposed behind the compressible unfixing area, for fixing the optical fiber to the ferrule.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: May 16, 2000
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Ohtsuka, Tomohiko Ueda, Toshiaki Kakii, Hiroshi Katsura