Patents Assigned to The Furukawa Electric Co.
  • Publication number: 20090052847
    Abstract: An optical fiber ribbon and an optical fiber cable capable of suppressing deterioration of polarization mode dispersion and effective in improving the communication capacity in wavelength multiplex communication. In an optical fiber ribbon having a plurality of optical fibers 12 in a bundled form, and a ribbon coating layer 13 formed around the plurality of optical fibers so as to integrally combining the plurality of optical fibers, the glass transition temperature of the ribbon coating is within the range from 80 to 130° C.; the Young's modulus of the ribbon coating is within the range from 800 to 2100 MPa; the thickness a of the ribbon coating layer applied on the upper and lower sides of the plurality of optical fibers and the thickness b of the ribbon coating layer applied outside the optical fibers in the outermost positions in the optical fiber ribbon always satisfy 1<b/a?2; the ribbon coating layer thickness a is 10 ?m or less; and the ribbon coating layer thickness b is smaller than 20 ?m.
    Type: Application
    Filed: February 1, 2008
    Publication date: February 26, 2009
    Applicant: FURUKAWA ELECTRIC CO., LTD.
    Inventors: Yoshihiro ARASHITANI, Toshiaki Ozawa, Kunihiko Yujoubou, Zoltan Varallyay
  • Publication number: 20090046984
    Abstract: An optical transmission system employs an optical fiber as an optical transmission path that includes a holey fiber and a dispersion-compensating optical fiber. The holey fiber includes a core region that is formed at a center of the holey fiber and a cladding region having a plurality of holes around the core region at regular intervals. The dispersion-compensating optical fiber is connected close to the holey fiber and that collectively compensates wavelength dispersion of the holey fiber at an operation wavelength in at least two wavelength bands out of O band, E band, S band, C band, and L band within a predetermined range depending on a transmission rate.
    Type: Application
    Filed: September 11, 2008
    Publication date: February 19, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventor: Kazunori Mukasa
  • Publication number: 20090044455
    Abstract: A power supply apparatus for sliding door, comprising a body-side fixing unit fixed to a vehicle body, a door-side fixing unit fixed to a sliding door, and a flat cable having a connector on both ends thereof respectively, arranged to run from the vehicle body through the body-side fixing unit and the door-side fixing unit to the sliding door, wherein the flat cable is used in such a manner that a longitudinal direction in a cross sectional area in at least a bent portion of the flat cable is in accordance with a height direction of the vehicle body.
    Type: Application
    Filed: March 5, 2008
    Publication date: February 19, 2009
    Applicant: The Furukawa Electric Co., Ltd.
    Inventors: Noritsugu Enomoto, Masatoshi Ushiyama, Yasuhiko Mukai
  • Patent number: 7492999
    Abstract: An optical fiber transmits at least a signal light having a wavelength of 1550 nanometers in a fundamental propagation mode. The optical fiber has, a cutoff wavelength equal to or longer than 1550 nanometers, a wavelength dispersion of 4 ps/nm/km to 7 ps/nm/km in the fundamental propagation mode at the wavelength of 1550 nanometers, a dispersion slope of a positive value equal to or smaller than 0.03 ps/nm2/km in the fundamental propagation mode at the wavelength of 1550 nanometers, an effective core area equal to or larger then 60 ?m2 in the fundamental propagation mode at the wavelength of 1550 nanometers, and a bending loss equal to or smaller than 20 dB/m with a winding of 16 turns at a diameter of 20 millimeters in the fundamental propagation mode at the wavelength of 1550 nanometers.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: February 17, 2009
    Assignee: The Furukawa Electric Co., Ltd.
    Inventor: Katsunori Imamura
  • Patent number: 7492983
    Abstract: The present invention provide an optical circuit device having: an optical circuit; a polarization beam splitter/combiner for splitting an incoming light beam into two polarization beams and combining the two polarization beams into an outgoing light beam; a first optical waveguide and a second optical waveguide for connecting the optical circuit and the polarization beam splitter/combiner and receiving the two polarization beams independently; and a polarization rotator, arranged on the first optical waveguide, for rotating a polarization plane of one of the two polarization beams split by the polarization beam splitter/combiner so as to match a polarization plane of the other of the two polarization beams, the optical circuit, the polarization beam splitter/combiner, the first optical waveguide, the second optical waveguide and the polarization rotator being integrated on a planar substrate.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: February 17, 2009
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Noritaka Matsubara, Hiroshi Kawashima, Kazutaka Nara
  • Publication number: 20090038743
    Abstract: A glass block is formed by stacking, fixing, and integrating a plurality of thin glass plates having a predetermined thickness. An annular glass block is formed by coring the glass block. Surfaces of an inside circumference and an outside circumference of the annular glass block are ground. The annular glass block of which the surfaces of the inside circumference and the outside circumference are ground are separated into individual annular glass substrates, and separated annular glass substrates are cleaned. Then, edge portions of the inside circumference and the outside circumference of a cleaned annular glass substrate are chamfered.
    Type: Application
    Filed: October 10, 2008
    Publication date: February 12, 2009
    Applicants: THE FURUKAWA ELECTRIC CO., LTD., KOHKEN KOGYO CO., LTD.
    Inventors: Tetsuo SUZUKI, Yoshio Kawakami
  • Publication number: 20090043002
    Abstract: A thermoplastic resin sheet which has both a high reflectance ratio and excellent shape-holding property suitable for backlights and illumination boxes for use in illumination signboards, illumination fixtures and displays and illumination boxes. The thermoplastic resin foam is manufactured by a manufacturing method including a process for containing inert gas by holding thermoplastic resin sheet containing metallic oxide in a pressurized inert gas atmosphere and a process for heating the thermoplastic resin sheet in which the inert gas is contained at a temperature higher than the softening temperature of the thermoplastic resin, under normal pressure, and foaming the resin.
    Type: Application
    Filed: August 31, 2005
    Publication date: February 12, 2009
    Applicant: The Furukawa Electric Co., Ltd.
    Inventors: Kohji Masuda, Masayasu Ito, Naoki Yoshida
  • Publication number: 20090042493
    Abstract: A chamfering apparatus is used to chamfer a peripheral edge of a glass substrate. The chamfering apparatus includes a grindstone having a cylindrical hollow end portion; a grindstone driving unit that rotates the grindstone around an axis of the cylindrical hollow end portion; a substrate rotation-driving unit that rotates the glass substrate around either one of an axis of the outer periphery and an axis of the center circular hole; and a pressing unit that presses the grindstone to the glass substrate such that an annular end surface of the grindstone contacts with an edge of either one of the outer periphery and the inner periphery of the glass substrate while the cylindrical hollow end portion of the grindstone faces with one of the outer periphery and the inner periphery of the glass substrate.
    Type: Application
    Filed: October 3, 2008
    Publication date: February 12, 2009
    Applicants: SHODA TECHTRON CORP., KOHKEN KOGYO CO., LTD., THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Kazuhiro NAKIRI, Yoshio Kawakami, Tetsuo Suzuki
  • Publication number: 20090032731
    Abstract: Provided is a photodetector 10 for detecting fluorescence 40 emitted from a sample 3 placed on a substrate of DNA chip 1 has an irradiation optical system 11 for guiding irradiation light 25 by a first optical waveguide 21, gathering the irradiation light by a first lens 22 and irradiating the sample 3; and a reception optical system 12 for gathering fluorescence 40 at an input-side end surface 31C of a second optical waveguide 31 by a second lens 32 and guiding the fluorescence 40 to a measuring unit 33. The irradiation optical system 11 and the reception optical system 12 are separate light guiding paths, and the reception optical system 12 is of a confocal optical system in which a focal point on the sample 3 is identical to a focal point at the input-side end surface 31C of the second optical waveguide 31 of the reception optical system 12.
    Type: Application
    Filed: August 7, 2008
    Publication date: February 5, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Kenichi KIMURA, Ken TSUKII, Shinichi TAGUCHI, Jie XU, Motosuke KIYOHARA
  • Publication number: 20090034922
    Abstract: It is an object of the present invention to provide an optical fiber cable which can reliably prevent increased transmission loss due to damage of the optical fiber as a result of the egg-laying behavior of cicadas. The cable includes at least an optical fiber 1, tension members 6 and a sheath 3. The sheath 3 has a shore D hardness of 55 or more and a minimum distance L from a surface of the optical fiber 1 to an outer surface of the sheath 3 of greater than 0.3 mm. Further, in the cable, the surface of sheath 3 has a coefficient of friction of 0.45 or less and the sheath 3 has a shore D hardness of 57 or more. In addition, the cable is made by using a specific flame retardant composition (P) as the sheath material.
    Type: Application
    Filed: October 9, 2008
    Publication date: February 5, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Tetsuya YASUTOMI, Masayoshi Tsukamoto, Mitsuru Iwano, Yoshihisa Rintsu, Masanobu Aragaki, Masaki Nishiguchi
  • Publication number: 20090032984
    Abstract: A method for manufacturing optical fibers with filter, wherein a multilayer-film filter is formed at end face of the optical fibers, comprising a process for fixing each of the optical fibers on a fixing jig, a process for polishing the end face of the optical fiber fixed on said fixing jig, a process for film-forming a filter on the end face of the optical fibers after polishing, and a process for taking out said optical fibers from said fixing jigs, respectively, wherein said process for film-forming the filter is performed by forming a fiber bundle in which a plural number of optical fibers after polishing, on which the filter has been film-formed, are tied such that all polished planes are aligned at the end face.
    Type: Application
    Filed: July 9, 2008
    Publication date: February 5, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Masayuki Iwase, Atsushi Izawa, Yozo Ishikawa
  • Publication number: 20090034926
    Abstract: A holey fiber has a core region, a cladding region surrounding the core region, air holes arranged around the core region, and a connection section extending from at least one end portion of the holey fiber. A refractive index of the core region in the connection section is higher than a refractive index of the cladding region without air holes in the connection section.
    Type: Application
    Filed: July 10, 2008
    Publication date: February 5, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventor: Kazunori MUKASA
  • Publication number: 20090028509
    Abstract: An optical fiber device converts an input optical pulse having a predetermined center wavelength into an optical pulse having a wavelength bandwidth broader than that of the input optical pulse. The optical fiber device includes a plurality of optical fibers connected in a cascaded manner each having negative wavelength dispersion at the center wavelength. The optical fibers have different relative refractive index differences between a core region and a cladding region from each other. The optical fibers are connected such that wavelength dispersions of adjacent optical fibers at the center wavelength are different from each other.
    Type: Application
    Filed: July 7, 2008
    Publication date: January 29, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Masateru TADAKUMA, Masanori TAKAHASHI
  • Publication number: 20090027007
    Abstract: Regarding a method for determining battery discharge capability of the present invention, the optimum state vector X is estimated by extended Kalman filter operation. Using the estimated state vector X, element parameters of an equivalent circuit are renewed to the optimum (step S7). Furthermore, based on the equivalent circuit 21 using the renewed element parameters, at the time of discharging with a predetermined current pattern from a battery 12, a voltage drop ?V is estimated (step S8). Therefore the discharge capacity of the battery 12 is determined (step S9).
    Type: Application
    Filed: July 8, 2008
    Publication date: January 29, 2009
    Applicant: THE FURUKAWA ELECTRIC CO, LTD.
    Inventors: Noriyasu IWANE, Koji FUJIMURA, Takezo SUGIMURA
  • Publication number: 20090030626
    Abstract: The present invention provides a battery remaining electrical charge/remaining capacity estimating method which makes it possible to obtain a convergence value of a battery open circuit voltage with high accuracy and in a short time. The method includes a voltage estimating step of obtaining a stable open circuit voltage estimated value after a lapse of desired time, the step including: a step of using an approximate function including a plurality of exponential function terms of time and a plurality of coefficients, stopping charge or discharge operation for a predetermined time, measuring a battery voltage over time during the time and using an obtained relation between the battery voltage and the time as a basis to determine the coefficients; and a step of determining at least one power coefficient of inferior logarithm of the exponential function terms based on temperature by expressing the coefficient as a previously obtained function of temperature.
    Type: Application
    Filed: December 3, 2007
    Publication date: January 29, 2009
    Applicant: The Furukawa Electric Co, Ltd.
    Inventors: Noriyasu Iwane, Yuichi Watanabe, Toshiyuki Sato, Atsushi Kimura, Fumikazu Iwahana
  • Patent number: 7483608
    Abstract: The present invention provides a method for designing an optical pulse shaper including a first optical propagation line unit having a nonlinear medium and a dispersion medium concatenated, including: specifying design specifications of the first optical propagation line unit; and based on the design specification, calculating a quasi-periodic stationary pulse of which a waveform of an input optical pulse to the first optical propagation line unit is similar to a waveform of an output pulse from the first optical propagation line unit.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: January 27, 2009
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Takashi Inoue, Shu Namiki
  • Patent number: 7481682
    Abstract: A joint connector according to the present invention is provided with a circuit board, a male connector having male terminals provided on the circuit board at a predetermined interval and standing in one direction and a direction that crosses the one direction, the male terminals being selectively connected by a copper foil circuit, and a female connector in which female connector elements each having female terminals inserted and interlocked in female terminal holders are stacked, wherein the male connector and the female connector are fit to each other. This achieves cost reduction and improvement in work efficiency in electric wire connection by attaining easy electric wire connection and branching.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: January 27, 2009
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Masakazu Murakami, Takahiro Imai, Tamaki Takabayashi, Takenobu Yabu, Syougo Tomita, Seiichi Ueno, Katsunori Takeda
  • Publication number: 20090022461
    Abstract: An optical fiber which reduces transmission loss increase even in a high humidity environment or under water is provided. To solve the above issue, an optical fiber according to the present invention comprises a glass optical fiber coated with at least two coating layers, soft and hard layers. The optical fiber is further coated by a colored resin to make a colored optical fiber. The hard layer and the color layer of the colored optical fiber have a free volume radius of at least 0.290 nm according to positron annihilation lifetime spectroscopy.
    Type: Application
    Filed: September 22, 2008
    Publication date: January 22, 2009
    Applicant: THE FURUKAWA ELECTRIC CO., LTD.
    Inventors: Yasuo NAKAJIMA, Kouji Mochizuki, Hiroki Tanaka
  • Publication number: 20090021722
    Abstract: A specimen optical information recognizing device comprises a specimen containing section (14) containing a specimen (12) to be measured, a specimen measuring section (20) having a light source (16) for outputting light for observing the specimen (12) and a photodetecting section (18) for collecting optical information from the specimen (12), and an optical waveguide (22) for propagating light between the specimen containing section (14) and the specimen measuring section (20). The optical information on the specimen is recognized by using the measurement values acquired under at least two measurement conditions. The specimen optical information recognizing device may further comprises a measurement auxiliary liquid interposed between the end of the optical waveguide and the specimen. Further, the specimen containing section may have a feature that the longitudinal cross section is of a recessed shape, and the aperture depth of the recessed portion is greater than the aperture diameter.
    Type: Application
    Filed: August 1, 2005
    Publication date: January 22, 2009
    Applicant: The Furukawa Electric Co., Ltd
    Inventors: Ken Tsukii, Jie Xu, Kenichi Kimura, Satoshi Sugiyama
  • Patent number: 7480091
    Abstract: In a method of phase adjustment for the demodulator 1 of the present invention, the phase adjustment is performed by driving any one of the heaters on the two waveguides 10 and 11 in the Mach-Zehnder interferometer (MZI) 6 and on the two waveguides 14 and 15 in the MZI 7. In case that an initial phase difference between the MZIs 6 and 7 smaller than a required phase difference as ?/2 therebetween, the heaters C and D are driven, that are formed on the first waveguide 10 in the MZI 6, and the heaters G and H are driven, that are formed on the second waveguide 15 in the MZI 7. In case that the initial phase difference is larger than the required phase difference (?/2) therebetween, the heaters A and B formed on the second waveguide 11 in the MZI 6, and the heaters E and F formed on the first waveguide 14 in the MZI 7 are driven.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: January 20, 2009
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Junichi Hasegawa, Kazutaka Nara