Patents by Inventor Atsushi Kiyama

Atsushi Kiyama 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: 11909515
    Abstract: An optical transmission system includes a transmitting node that transmits wavelength light of an operational path to an optical waveguide, and a receiving node that receives the wavelength light from the optical waveguide. The transmitting node includes a light source that generates spontaneously emitted light and a wavelength selector that generates and outputs dummy wavelength light from the spontaneously emitted light generated by the light source. The receiving node includes an extractor that extracts spectral data of the dummy wavelength light passed in the optical waveguide. The optical transmission system further includes an obtainer that obtains a band state of the operational path from the spectral data of the dummy wavelength light extracted by the extractor.
    Type: Grant
    Filed: July 18, 2022
    Date of Patent: February 20, 2024
    Assignee: FUJITSU LIMITED
    Inventors: Tomoaki Watanabe, Atsushi Kiyama, Makoto Hasegawa, Yoshito Kachita
  • Publication number: 20230239066
    Abstract: An optical transmission system includes a transmitting node that transmits wavelength light of an operational path to an optical waveguide, and a receiving node that receives the wavelength light from the optical waveguide. The transmitting node includes a light source that generates spontaneously emitted light and a wavelength selector that generates and outputs dummy wavelength light from the spontaneously emitted light generated by the light source. The receiving node includes an extractor that extracts spectral data of the dummy wavelength light passed in the optical waveguide. The optical transmission system further includes an obtainer that obtains a band state of the operational path from the spectral data of the dummy wavelength light extracted by the extractor.
    Type: Application
    Filed: July 18, 2022
    Publication date: July 27, 2023
    Applicant: FUJITSU LIMITED
    Inventors: Tomoaki WATANABE, Atsushi Kiyama, Makoto HASEGAWA, Yoshito Kachita
  • Publication number: 20230208548
    Abstract: An optical transmission device includes: a selector configured to select a wavelength of a signal to be transmitted to an optical transmission line and output a wavelength-multiplexed signal; an adjustor configured to control a power level of the wavelength-multiplexed signal; and a controller configured to control the adjustor or the selector, wherein the selector selects a wavelength of an optical signal in a second wavelength band different from an existing first wavelength band, and when the second wavelength band is added to or removed from the optical transmission line, the controller controls power of the wavelength-multiplexed signal in the second wavelength band at a slower speed than power control in the first wavelength band.
    Type: Application
    Filed: September 28, 2022
    Publication date: June 29, 2023
    Applicant: FUJITSU LIMITED
    Inventors: Atsushi Kiyama, NOBUYUKI FUKUCHI, Tomoaki WATANABE
  • Publication number: 20200169320
    Abstract: An optical signal is transmitted between first and second transmission devices. When a network control device receives a shutdown report that indicates a loss of light from both of the first and second transmission devices, the network control device transmits a first instruction to resume a transmission of a control signal to both of the first and second transmission devices. When the network control device receives a detection report that indicates a reception of the control signal from both of the first and second transmission devices, the network control device transmits a second instruction to resume a transmission of a WDM signal to both of the first and second transmission devices.
    Type: Application
    Filed: October 18, 2019
    Publication date: May 28, 2020
    Applicant: FUJITSU LIMITED
    Inventor: Atsushi Kiyama
  • Patent number: 10461879
    Abstract: An optical transmission device includes: a first optical amplifier, a WSS (wavelength selective switch), a second optical amplifier and a controller. The first optical amplifier amplifies a received WDM (wavelength division multiplexed) optical signal. The WSS controls optical powers of respective channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier. The second optical amplifier amplifies the WDM optical signal output from the WSS. The controller controls a gain of the first optical amplifier based on initial setting information. The controller corrects the gain of the first optical amplifier such that an average optical power of a plurality of channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier approaches a target level after a specified period of time has elapsed from when the gain of the first optical amplifier is controlled based on the initial setting information.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: October 29, 2019
    Assignee: FUJITSU LIMITED
    Inventors: Masahiro Yuki, Atsushi Kiyama
  • Publication number: 20180205485
    Abstract: An optical transmission device includes: a first optical amplifier, a WSS (wavelength selective switch), a second optical amplifier and a controller. The first optical amplifier amplifies a received WDM (wavelength division multiplexed) optical signal. The WSS controls optical powers of respective channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier. The second optical amplifier amplifies the WDM optical signal output from the WSS. The controller controls a gain of the first optical amplifier based on initial setting information. The controller corrects the gain of the first optical amplifier such that an average optical power of a plurality of channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier approaches a target level after a specified period of time has elapsed from when the gain of the first optical amplifier is controlled based on the initial setting information.
    Type: Application
    Filed: December 22, 2017
    Publication date: July 19, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Masahiro YUKI, Atsushi Kiyama
  • Patent number: 9900089
    Abstract: An optical transmission device that transmits an optical signal in a specified wavelength band includes: a receiver, a monitor light unit, a wavelength selective switch and a memory. The receiver receives the optical signal. The monitor light unit outputs monitor light of a wavelength allocated outside of the specified wavelength band. The wavelength selective switch outputs the optical signal via a first port and outputs the monitor light via a second port. The memory stores information that indicates an optical power loss of a route through which the monitor light is transmitted.
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: February 20, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Masahiro Yuki, Yoshinobu Matsukawa, Atsushi Kiyama
  • Publication number: 20170250752
    Abstract: An optical transmission device that transmits an optical signal in a specified wavelength band includes: a receiver, a monitor light unit, a wavelength selective switch and a memory. The receiver receives the optical signal. The monitor light unit outputs monitor light of a wavelength allocated outside of the specified wavelength band. The wavelength selective switch outputs the optical signal via a first port and outputs the monitor light via a second port. The memory stores information that indicates an optical power loss of a route through which the monitor light is transmitted.
    Type: Application
    Filed: January 18, 2017
    Publication date: August 31, 2017
    Applicant: FUJITSU LIMITED
    Inventors: Masahiro YUKI, Yoshinobu MATSUKAWA, Atsushi KIYAMA
  • Publication number: 20160315701
    Abstract: An optical transmission device according to an aspect of the present invention includes a plurality of substrate modules that are optically connected to one another. A first substrate module in the plurality of substrate modules includes a light generator generating a test light and a first optical switch transferring the generated test light. A second substrate module in the plurality of substrate modules includes a second optical switch looping back, to the first substrate module, the test light transferred from the first substrate module.
    Type: Application
    Filed: April 5, 2016
    Publication date: October 27, 2016
    Applicant: FUJITSU LIMITED
    Inventors: Masahiro YUKI, Yoshinobu MATSUKAWA, Atsushi Kiyama
  • Patent number: 7394536
    Abstract: The present invention provides an inspection method and an inspection apparatus which can remove influence of rear surface reflection image and inspect characteristic of a front surface shape with good accuracy by an inexpensive apparatus construction. First of all, as a stripe pattern suitable for a transparent plate-shaped object 3 (object to be inspected), a stripe pattern 1 having a bright-dark pattern configured so that its reflection image produced by the front surface of the transparent plate-shaped object and its reflection image produced by a rear surface of the transparent plate-shaped object are separated in an image signal obtained by image-capturing, is determined. Thereafter, using the decided stripe pattern 1, the front surface shape of the transparent plate-shaped object 3 is evaluated by an image analysis using only a reflection image of the stripe pattern 1 produced by the transparent plate-shaped object 3.
    Type: Grant
    Filed: November 20, 2006
    Date of Patent: July 1, 2008
    Assignee: Asahi Glass Company, Limited
    Inventors: Yoshiyuki Sonda, Kimiaki Oto, Munehisa Kato, Atsushi Kiyama
  • Publication number: 20070091319
    Abstract: The present invention provides an inspection method and an inspection apparatus which can remove influence of rear surface reflection image and inspect characteristic of a front surface shape with good accuracy by an inexpensive apparatus construction. First of all, as a stripe pattern suitable for a transparent plate-shaped object 3 (object to be inspected), a stripe pattern 1 having a bright-dark pattern configured so that its reflection image produced by the front surface of the transparent plate-shaped object and its reflection image produced by a rear surface of the transparent plate-shaped object are separated in an image signal obtained by image-capturing, is determined. Thereafter, using the decided stripe pattern 1, the front surface shape of the transparent plate-shaped object 3 is evaluated by an image analysis using only a reflection image of the stripe pattern 1 produced by the transparent plate-shaped object 3.
    Type: Application
    Filed: November 20, 2006
    Publication date: April 26, 2007
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Yoshiyuki SONDA, Kimiaki Oto, Munehisa Kato, Atsushi Kiyama