Patents by Inventor Atsushi Hamakawa

Atsushi Hamakawa 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).

  • Patent number: 6876682
    Abstract: A light generating module 1 comprises a housing 2, a semiconductor light-emitting device 4, a driving element 6, and a monitoring light-receiving device 8. The monitoring light-receiving device 8 is optically coupled with the semiconductor light-emitting device 4. The driving element 6 drives the semiconductor light-emitting device 4. The housing 2 contains the semiconductor light-emitting device 4, the driving element 6, and the monitoring light-receiving device 8. These elements 4, 6, and 8 are disposed sequentially along a predetermined axis. The driving element 6 is disposed between the semiconductor light-emitting device 4 and the monitoring light-receiving device 8. This configuration makes it possible to dispose the driving element 6 close to the semiconductor light-emitting device 4 so as to achieve a transmission rate of 10 Gbps without degrading the optical coupling between the semiconductor light-receiving device 8 and the semiconductor light-emitting device 4.
    Type: Grant
    Filed: February 22, 2002
    Date of Patent: April 5, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Nakabayashi, Atsushi Hamakawa
  • Publication number: 20020167977
    Abstract: A light generating module 1 comprises a housing 2, a semiconductor light-emitting device 4, a driving element 6, and a monitoring light-receiving device 8. The monitoring light-receiving device 8 is optically coupled with the semiconductor light-emitting device 4. The driving element 6 drives the semiconductor light-emitting device 4. The housing 2 contains the semiconductor light-emitting device 4, the driving element 6, and the monitoring light-receiving device 8. These elements 4, 6, and 8 are disposed sequentially along a predetermined axis. The driving element 6 is disposed between the semiconductor light-emitting device 4 and the monitoring light-receiving device 8. This configuration makes it possible to dispose the driving element 6 close to the semiconductor light-emitting device 4 so as to achieve a transmission rate of 10 Gbps without degrading the optical coupling between the semiconductor light-receiving device 8 and the semiconductor light-emitting device 4.
    Type: Application
    Filed: February 22, 2002
    Publication date: November 14, 2002
    Inventors: Takashi Nakabayashi, Atsushi Hamakawa
  • Patent number: 5995692
    Abstract: The present invention relates to a light emitting device module which can easily be made and can yield a stable output characteristic, and a method of making the same. The light emitting device module in according to the present invention comprises a semiconductor device in which an active region having a light exit facet and a light reflecting facet with a lower light reflectivity than the light exit facet respectively at both ends is fabricated along a predetermined reference axis, and an optical fiber having a grating provided along the longitudinal direction of the core region and an end facet arranged so as to face the light exit facet. In particular, in the light emitting device module according to the present invention, the light exit facet of the active region is inclined with respect to the light reflecting facet of the active region by a predetermined angle, thereby the light reflecting facet of the active region and the grating constitute an external cavity through the light exit facet.
    Type: Grant
    Filed: June 18, 1997
    Date of Patent: November 30, 1999
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Atsushi Hamakawa, Takashi Kato, Michio Murata, Hidetoshi Kobayashi
  • Patent number: 5993073
    Abstract: A semiconductor laser module in which: the distance between a semiconductor laser chip and a diffraction grating can be shortened; the light output spectrum is stabilized; and the output characteristic does not fluctuate due to the external condition. In the semiconductor laser module, a diffraction grating structure is constituted in an optical fiber by at least two diffraction gratings for reflecting light with different wavelengths respectively. The diffraction grating structure is formed in a place corresponding to the inside of the package or the inside of the coupling means.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: November 30, 1999
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Atsushi Hamakawa, Masakazu Shigehara
  • Patent number: 5845030
    Abstract: A semiconductor laser module includes a semiconductor laser having an active region between a light-reflecting surface and a light-exit surface thereof, and an optical fiber optically coupled to the semiconductor laser and including an optical fiber diffraction grating. The optical fiber diffraction grating selectively reflects light within a predetermined wavelength band. The wavelength band has a width larger than a wavelength interval of a longitudinal mode of light resonating between the light-reflecting surface and the light-exit surface.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: December 1, 1998
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Goro Sasaki, Atsushi Hamakawa