Patents by Inventor Masakazu Oohashi

Masakazu Oohashi 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).

  • Optical fiber and optical fiber coupler, erbium-doped optical fiber amplifier, and optical waveguide using the same
    Patent number: 7711238
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: May 4, 2010
    Assignee: Fujikura Ltd.
    Inventors: Masashi Ikeda, Masakazu Nakayama, Kuniharu Himeno, Masaaki Ohtsuka, Masakazu Oohashi, Daiichiro Tanaka
  • Optical fiber and optical fiber coupler, erbium-doped optical fiber amplifier, and optical waveguide using the same
    Patent number: 7406236
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: July 29, 2008
    Assignee: Fujikura Ltd.
    Inventors: Masashi Ikeda, Masakazu Nakayama, Kuniharu Himeno, Masaaki Ohtsuka, Masakazu Oohashi, Daiichiro Tanaka
  • Optical fiber and optical fiber coupler, erbium-doped optical fiber amplifier, and optical waveguide using the same
    Patent number: 7346258
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Grant
    Filed: January 5, 2005
    Date of Patent: March 18, 2008
    Assignee: Fujikura Ltd.
    Inventors: Masashi Ikeda, Masakazu Nakayama, Kuniharu Himeno, Masaaki Ohtsuka, Masakazu Oohashi, Daiichiro Tanaka
  • OPTICAL FIBER AND OPTICAL FIBER COUPLER, ERBIUM-DOPED OPTICAL FIBER AMPLIFIER, AND OPTICAL WAVEGUIDE USING THE SAME
    Publication number: 20080025679
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Application
    Filed: September 28, 2007
    Publication date: January 31, 2008
    Applicant: FUJIKURA LTD.
    Inventors: Masashi IKEDA, Masakazu NAKAYAMA, Kuniharu HIMENO, Masaaki OHTSUKA, Masakazu OOHASHI, Daiichiro TANAKA
  • OPTICAL FIBER AND OPTICAL FIBER COUPLER, ERBIUM-DOPED OPTICAL FIBER AMPLIFIER, AND OPTICAL WAVEGUIDE USING THE SAME
    Publication number: 20060140565
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Application
    Filed: February 16, 2006
    Publication date: June 29, 2006
    Inventors: Masashi Ikeda, Masakazu Nakayama, Kuniharu Himeno, Masaaki Ohtsuka, Masakazu Oohashi, Daiichiro Tanaka
  • Optical fiber and optical fiber coupler, erbium-doped optical fiber amplifier, and optical waveguide using the same
    Publication number: 20050135762
    Abstract: An optical fiber that includes a core containing a first concentration of germanium, an inner cladding arranged on the core, the inner cladding containing a second concentration of germanium and having a first diffusion coefficient, and an outer cladding arranged on the inner cladding, the outer cladding having a second diffusion coefficient, where the first diffusion coefficient is larger than the second diffusion coefficient, and where the first concentration of germanium is about 200% or more of the second concentration of germanium. An optical fiber constructed in this manner can be spliced with an optical fiber having a different MFD, such as a single-mode optical fiber or an erbium-doped optical fiber, with low splice loss and a sufficient splicing strength.
    Type: Application
    Filed: January 5, 2005
    Publication date: June 23, 2005
    Inventors: Masashi Ikeda, Masakazu Nakayama, Kuniharu Himeno, Masaaki Ohtsuka, Masakazu Oohashi, Daiichiro Tanaka