Patents by Inventor Shoichiro Matsuo

Shoichiro Matsuo 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: 20140003807
    Abstract: For example, of a first intensity distribution waveform WF1 indicated by a distance distribution of an intensity of light which returns to one end of a core of a multicore fiber, and a second intensity distribution waveform WF2 indicated by a distance distribution of an intensity of light which returns to the other end of the core, the second intensity distribution waveform WF2 is inverted. Further, for example, an inverted intensity distribution waveform WF3 which is inverted and the first intensity distribution waveform WF1 which is not inverted are added.
    Type: Application
    Filed: June 21, 2013
    Publication date: January 2, 2014
    Inventors: Hiroki Hamaguchi, Shoichiro Matsuo, Itaru Ishida, Yukihiro Goto, Kazuhide Nakajima
  • Publication number: 20130272668
    Abstract: An optical fiber of the invention satisfies ?core>?ic>?tmax>?tmin, ?0.15%??tmax>?tmin??0.7%, and 0.45?(rtmax?rin)/(rout?rin)?0.9 where the relative refractive index difference of the core is ?core, the relative refractive index difference of the internal cladding coat is ?ic, the relative refractive index difference of a highest refractive index layer in the trench coating is ?tmax, the relative refractive index difference of a lowest refractive index layer in the trench coating is ?tmin, the radius of an internal edge of the trench coating is rin, the radius of an external edge of the trench coating is rout, and the radius of an internal edge of a highest refractive index layer in the trench coating is rtmax and where the relative refractive index differences are based on a refractive index of the outermost cladding coat.
    Type: Application
    Filed: June 7, 2013
    Publication date: October 17, 2013
    Inventors: Mamoru SATO, Shoichiro MATSUO
  • Publication number: 20130243384
    Abstract: A multicore fiber includes a plurality of core elements; and a clad surrounding an outer periphery surface of each of the core elements, and each of the core elements includes a core, a first clad surrounding the outer periphery surface of the core and a second clad surrounding an outer periphery surface of the first clad, and when a refractive index of the core is n1, a refractive index of the first clad is n2, a refractive index of the second clad is n3 and a refractive index of the clad is n4, all of n1>n2>n3, n1>n4 and n3<n4 are satisfied.
    Type: Application
    Filed: May 2, 2013
    Publication date: September 19, 2013
    Applicants: NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY, FUJIKURA LTD.
    Inventors: Shoichiro Matsuo, Katsuhiro Takenaga, Kunimasa Saitoh, Masanori Koshiba
  • Publication number: 20130243380
    Abstract: An optical fiber (1) includes (i) an inner core (111) whose refractive index distribution has an a profile, (ii) an outer core (112) which surrounds the inner core (111), and (iii) a clad (12) which surrounds the outer core (112). In the optical fiber (1), Rd is set to not less than 0.15, where Rd is a ratio of a refractive index difference between the outer core (112) and the clad (12) to a refractive index difference between a center part of the inner core (111) and the clad (12).
    Type: Application
    Filed: May 6, 2013
    Publication date: September 19, 2013
    Applicants: Osaka Prefecture University Public Corporation, Fujikura Ltd.
    Inventors: Ryo MARUYAMA, Nobuo KUWAKI, Shoichiro MATSUO, Masaharu OHASHI
  • Publication number: 20120288247
    Abstract: Each of a first clad region (12) and a second clad region (13) has holes (12a, 13a) which have identical diameters and are periodically formed so that the first clad region (12) and the second clad region (13) each have an effective refractive index lower than a refractive index of a core region (11), the effective refractive index of the first clad region (12) being lower than that of the second clad region (13).
    Type: Application
    Filed: July 26, 2012
    Publication date: November 15, 2012
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, FUJIKURA LTD.
    Inventors: Shoji TANIGAWA, Katsuhiro TAKENAGA, Shoichiro MATSUO, Takashi MATSUI, Taiji SAKAMOTO, Kyouzou TSUJIKAWA, Shigeru TOMITA
  • Publication number: 20120262706
    Abstract: A cut-off wavelength measuring method according to the present invention includes: preparing a single mode fiber as a reference fiber; preparing a measurement target fiber; adjusting the length of the single mode fiber such that the length of the single mode fiber is longer than the that of the measurement target fiber at the time of measuring power of transmission light and the reference fiber propagates only light of a base mode at a predicted cut-off wavelength of the measurement target fiber; measuring wavelength dependence of power of light transmitted through the reference fiber and wavelength dependence of power of light transmitted through the measurement target fiber; and calculating a cut-off wavelength of the measurement target fiber based on wavelength dependence represented as the ratio of the power of transmission light transmitted through the measurement target fiber to the power of light transmitted through the reference fiber.
    Type: Application
    Filed: April 5, 2012
    Publication date: October 18, 2012
    Applicant: Fujikura Ltd.
    Inventors: Yasuko SUGIMOTO, Shoichiro MATSUO
  • Patent number: 8195019
    Abstract: A plastic glass optical fiber includes a glass core (diameter a1, relative refractive index difference ?1, and refractive index n1), a polymer core (diameter a2, relative refractive index difference ?2, and refractive index n2), and a polymer cladding (refractive index n3), in which the diameter a1 of the glass core is within a range of 110 ?m to 200 ?m, a parameter X (X is a22/a12) is within a range of 1.15?X?2.9, a parameter Y (Y is ?2/?1) is within a range of 0.25?Y?0.84X?0.68 (when 1.15?X?2) or 0.48X?0.71?Y??(2/9)X+13/9 (when 2?X?2.9), a parameter ZR (ZR is Z2core/Z1core; Z2core=a22?/4×?(n12?n32) and Z1core=a12?/4×?(n12?n22)) is within a range of 1.25?ZR?4.
    Type: Grant
    Filed: December 28, 2009
    Date of Patent: June 5, 2012
    Assignee: Fujikura Ltd.
    Inventors: Kenji Okada, Naritoshi Yamada, Shoichiro Matsuo
  • Publication number: 20120044482
    Abstract: A measuring method of a hole diameter of a holey optical fiber includes calculating an arithmetical mean value I(x) from two backscattering light intensities at a position x of two backscattering light waveforms of the holey optical fiber, in which the two backscattering light waveforms are obtained by OTDR measurement; and obtaining the hole diameter at the position x, based on a correlation between an arithmetical mean value I(x) and an hole diameter of the holey optical fiber that is obtained in advance.
    Type: Application
    Filed: August 19, 2011
    Publication date: February 23, 2012
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, FUJIKURA LTD.
    Inventors: Itaru ISHIDA, Shoji TANIGAWA, Shoichiro MATSUO, Toshio KURASHIMA, Kazuhide NAKAJIMA, Tomoya SHIMIZU, Takashi MATSUI, Yukihiro GOTO
  • Publication number: 20120042696
    Abstract: A measuring method of a longitudinal distribution of bending loss of an optical fiber includes calculating an arithmetical mean value I(x) from two backscattering light intensities of two backscattering light at a position x obtained by bidirectional OTDR measurement of the optical fiber; and obtaining a bending loss value at the position x from a mode field diameter 2W(x) and a relative refractive index difference ?(x) at the position x calculated from the arithmetical mean value.
    Type: Application
    Filed: August 19, 2011
    Publication date: February 23, 2012
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, FUJIKURA LTD.
    Inventors: Shoji TANIGAWA, Itaru ISHIDA, Shoichiro MATSUO, Toshio KURASHIMA, Kazuhide NAKAJIMA, Tomoya SHIMIZU, Takashi MATSUI, Yukihiro GOTO
  • Patent number: 7817257
    Abstract: A method for measuring a multimode optical fiber includes: monitoring a temperature change within a measurement time in a DMD measurement of the multimode optical fiber, where the DMD measurement is carried out in an environment in which a magnitude of temperature change is controlled.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: October 19, 2010
    Assignee: Fujikura Ltd.
    Inventors: Katsuhiro Takenaga, Ning Guan, Shoichiro Matsuo, Kuniharu Himeno, Koichi Harada
  • Publication number: 20100104249
    Abstract: A plastic glass optical fiber includes a glass core (diameter a1, relative refractive index difference ?1, and refractive index n1), a polymer core (diameter a2, relative refractive index difference ?2, and refractive index n2), and a polymer cladding (refractive index n3), in which the diameter a1 of the glass core is within a range of 110 ?m to 200 ?m, a parameter X (X is a22/a12) is within a range of 1.15?X?2.9, a parameter Y (Y is ?2/?1) is within a range of 0.25?Y?0.84X?0.68 (when 1.15?X?2) or 0.48X?0.71?Y??(2/9)X+13/9 (when 2?X?2.9), a parameter ZR (ZR is Z2core/Z1core; Z2core=a22?/4×?(n12?n32) and Z1core=a12?/4×?(n12n?n22)) is within a range of 1.25?ZR?4.
    Type: Application
    Filed: December 28, 2009
    Publication date: April 29, 2010
    Applicant: FUJIKURA LTD.
    Inventors: Kenji OKADA, Naritoshi YAMADA, Shoichiro MATSUO
  • Patent number: 7606460
    Abstract: An optical fiber comprises a center core and a cladding located at an outer periphery of the core, wherein the core comprises at least one codoped layer made from silica glass doped with germanium and fluorine, and at least one lower-concentration codoped layer made from silica glass doped with germanium, or silica glass that is doped with germanium and fluorine wherein an amount of fluorine in the lower-concentration codoped layer is smaller than an amount of fluorine in the codoped layer.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: October 20, 2009
    Assignee: Fujikura Ltd.
    Inventors: Shoichiro Matsuo, Shoji Tanigawa, Kuniharu Himeno
  • Patent number: 7526168
    Abstract: An optical fiber has a first mode field diameter in a dominant mode of an acoustic mode generated in the optical fiber different from a second mode field diameter in a light intensity distribution of the optical fiber. Furthermore, a transmission system is configured to perform an analog signal transmission, a baseband transmission, or an optical SCM transmission by use of the optical fiber.
    Type: Grant
    Filed: May 3, 2007
    Date of Patent: April 28, 2009
    Assignee: Fujikura Ltd.
    Inventors: Shoichiro Matsuo, Shoji Tanigawa, Keisuke Uchiyama, Kuniharu Himeno
  • Patent number: 7505657
    Abstract: A single-mode optical fiber has a prescribed mode field diameter (MFD1 (?m)) at a first wavelength ?1, in which a bending loss when measured at a second wavelength ?2 (?m) and wound with a bending radius r (mm) is Lb (dB) for one bending, a connector/splice loss with an optical fiber that has a prescribed mode field diameter MFD2 (?m) at the first wavelength ?1 is Ls (dB) for one connection/splice point at the second wavelength ?2 (?m), and an mode field diameter dependence of a total loss coefficient calculated by a formula (1) has a local minimal value in a range of MFD1±0.5 ?m, with the formula (1) being as follows: L=ws·Ls+wb·Lb,??(1) ws+wb=1,??(2) ws>0, wb>0,??(3) where ws and wb in the formula (1) represent dimensionless weighting factors and are set within a range that satisfies the formulas (2) and (3).
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: March 17, 2009
    Assignee: Fujikura Ltd.
    Inventors: Shoichiro Matsuo, Kuniharu Himeno
  • Patent number: 7463346
    Abstract: In a method of measurement of the birefringence of an optical fiber, the round-trip Jones matrix R(z) for a first interval (0, z) from a measurement starting point 0 in the optical fiber for measurement to a prescribed position z, and the round-trip Jones matrix R(z+?z) for a second interval (0, z+?z) from the measurement starting point 0 to a position z+?z differing from the position z, are acquired, the eigenvalues ?1, ?2 of the matrix R(z+?z)R(z)?1 are determined, and by computing the following equations (1) and (2), ? = arg ? ( ? 1 ? 2 ) 2 ( 1 ) ? ? ? n = ?? 2 ? ? · ? ? ? z ( 2 ) (where ? represents the phase difference between linear polarization components due to birefringence, ?n represents birefringence, and ? represents wavelength), the birefringence in the infinitesimal interval ?z from the position z to the position z+?z is obtained.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: December 9, 2008
    Assignee: Fujikura Ltd.
    Inventors: Ryuichiro Goto, Shoichiro Matsuo, Kuniharu Himeno
  • Patent number: 7440663
    Abstract: A single-mode optical fiber has a cut-off wavelength of 1260 nm or less, a zero-dispersion wavelength in the range of 1300 nm to 1324 nm, a zero-dispersion slope of 0.093 ps/nm2/km or less, a mode field diameter at a wavelength of 1310 nm in the range of 5.5 ?m to 7.9 ?m, and a bending loss of 0.5 dB or less at a wavelength of 1550 nm, the bending loss being produced when the fiber is wound around a 10-mm radius for 10 turns.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: October 21, 2008
    Assignee: Fujikura Ltd.
    Inventors: Shoichiro Matsuo, Hiroshi Kutami, Kuniharu Himeno, Hiroyuki Sawano
  • Publication number: 20080101755
    Abstract: A single-mode optical fiber has a prescribed mode field diameter (MFD1 (?m)) at a first wavelength ?1, in which a bending loss when measured at a second wavelength ?2 (?m) and wound with a bending radius r (mm) is Lb (dB) for one bending, a connector/splice loss with an optical fiber that has a prescribed mode field diameter MFD2 (?m) at the first wavelength ?1 is Ls (dB) for one connection/splice point at the second wavelength ?2 (?m), and an mode field diameter dependence of a total loss coefficient calculated by a formula (1) has a local minimal value in a range of MFD1±0.5 ?m, with the formula (1) being as follows: L=ws·Ls+wb·Lb,??(1) ws+wb=1,??(2) ws>0, wb>0,??(3) where ws and wb in the formula (1) represent dimensionless weighting factors and are set within a range that satisfies the formulas (2) and (3).
    Type: Application
    Filed: December 5, 2007
    Publication date: May 1, 2008
    Applicant: Fujikura Ltd.
    Inventors: Shoichiro MATSUO, Kuniharu Himeno
  • Patent number: 7366387
    Abstract: A single-mode optical fiber has a prescribed mode field diameter (MFD1 (?m)) at a first wavelength ?1, in which a bending loss when measured at a second wavelength ?2 (?m) and wound with a bending radius r (mm) is Lb (dB) for one bending, a connector/splice loss with an optical fiber that has a prescribed mode field diameter MFD2 (?m) at the first wavelength ?1 is Ls (dB) for one connection/splice point at the second wavelength ?2 (?m), and an mode field diameter dependence of a total loss coefficient calculated by a formula (1) has a local minimal value in a range of MFD1±0.5 ?m, with the formula (1) being as follows: L=ws·Ls+wb·Lb,??(1) ws+wb=1,??(2) ws>0, wb>0??(3) where ws and wb in the formula (1) represent dimensionless weighting factors and are set within a range that satisfies the formulas (2) and (3).
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: April 29, 2008
    Assignee: Fujikura Ltd.
    Inventors: Shoichiro Matsuo, Kuniharu Himeno
  • Publication number: 20080030720
    Abstract: In a method of measurement of the birefringence of an optical fiber, the round-trip Jones matrix R(z) for a first interval (0, z) from a measurement starting point 0 in the optical fiber for measurement to a prescribed position z, and the round-trip Jones matrix R(z+?z) for a second interval (0, z+?z) from the measurement starting point 0 to a position z+?z differing from the position z, are acquired, the eigenvalues ?1, ?2 of the matrix R(z+?z)R(z)?1 are determined, and by computing the following equations (1) and (2), ? = arg ? ( ? 1 ? 2 ) 2 ( 1 ) ? ? ? ? n = ?? 2 ? ? · ? ? ? ? z ( 2 ) (where ? represents the phase difference between linear polarization components due to birefringence, ?n represents birefringence, and ? represents wavelength), the birefringence in the infinitesimal interval ?z from the position z to the position z+?z is obtained.
    Type: Application
    Filed: October 10, 2007
    Publication date: February 7, 2008
    Applicant: FUJIKURA LTD.
    Inventors: Ryuichiro GOTO, Shoichiro MATSUO, Kuniharu HIMENO
  • Publication number: 20080013906
    Abstract: An optical fiber has a first mode field diameter in a dominant mode of an acoustic mode generated in the optical fiber different from a second mode field diameter in a light intensity distribution of the optical fiber. Furthermore, a transmission system is configured to perform an analog signal transmission, a baseband transmission, or an optical SCM transmission by use of the optical fiber.
    Type: Application
    Filed: May 3, 2007
    Publication date: January 17, 2008
    Applicant: FUJIKURA LTD.
    Inventors: Shoichiro Matsuo, Shoji Tanigawa, Keisuke Uchiyama, Kuniharu Himeno