Patents by Inventor Taku Aoyama

Taku Aoyama 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: 9507179
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Grant
    Filed: January 2, 2015
    Date of Patent: November 29, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Publication number: 20150124307
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Application
    Filed: January 2, 2015
    Publication date: May 7, 2015
    Inventors: Taku AOYAMA, Koji CHINDO
  • Patent number: 8922284
    Abstract: A method of controlling an atomic oscillator includes generating a resonant light pair in response to a center frequency signal and a sideband signal, and setting the sideband signal so that an electromagnetically induced transparency (EIT) phenomenon does not occur in a gas cell of the atomic oscillator. The method includes applying the resonant light pair to the gas cell and detecting an intensity level of light transmitted through the gas cell. While the sideband signal is set so that the EIT phenomenon is not occurring, the center frequency signal is varied until a minimum value of the intensity level is identified. A first frequency is calculated by subtracting a predetermined frequency offset from the center frequency at which the intensity level was equal to the minimum value. A center frequency of the resonant light pair is set to the first frequency for operation of the atomic oscillator.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: December 30, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Patent number: 8860515
    Abstract: An atomic oscillator, a control method of the atomic oscillator and a quantum interference apparatus are provided in which high frequency stability can be maintained even though EIT signal intensity changes.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: October 14, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Tetsuya Takahashi
  • Patent number: 8810325
    Abstract: A quantum interference device causing electromagnetically induced transparency in an alkali metal atom includes: a light source generating first and second resonant lights with frequency differences ??; a magnetic field generator applying a magnetic field to the atom; a light detector detecting intensities of the first and second resonant lights passing through the atom; and a controller causing a frequency difference between specified first and second resonant lights to equal a frequency difference corresponding to an energy difference between two ground levels of the atom based on the detected light. The controller causes the frequency ?? or magnetic field intensity to satisfy 2×?×n=?? or ??×n=2×?. The frequency ? corresponds to an energy difference between two Zeeman split levels differentiated by one magnetic quantum number and generated in the two ground levels of the atom by energy splitting.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: August 19, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Patent number: 8643441
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: February 4, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Patent number: 8593229
    Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; first and second heaters heating the gas cell; an exciting light source exciting the metal atom; a light detector detecting the exciting light; a substrate including a temperature controlling circuit for the heaters; a first wiring coupling the first heater and the substrate; a second wiring coupling the second heater and the substrate; and a third wiring coupling the first heater and the second heater. In the atomic oscillator, the gas cell includes a cylinder and windows sealing both ends of the cylinder and constituting an incident surface and an emitting surface on an optical path of the exciting light. The first and second heaters are respectively formed on the windows at an incident surface side and an emitting surface side and are made of transparent heating materials.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: November 26, 2013
    Assignee: Seiko Epson Corporation
    Inventors: Koji Chindo, Taku Aoyama
  • Patent number: 8564376
    Abstract: A physical section of an atomic oscillator includes: a gas cell in which gaseous metal atoms are sealed, and the gas cell includes a first window having optical transparency; a light source that emits excitation light toward the metal atoms through the first window; a first heating unit that disposes at the first window and that is located between the first window and the light source; and a Peltier element that is stacked on the first heating unit, that is located between the first heating unit and the light source, and that decreases a temperature of a side of the Peltier element facing the light source than a temperature of an opposite side of the Peltier element facing the gas cell.
    Type: Grant
    Filed: July 7, 2011
    Date of Patent: October 22, 2013
    Assignee: Seiko Epson Corporation
    Inventors: Koji Chindo, Taku Aoyama
  • Publication number: 20120319785
    Abstract: A quantum interference device causing electromagnetically induced transparency in an alkali metal atom includes: a light source generating first and second resonant lights with frequency differences ??; a magnetic field generator applying a magnetic field to the atom; a light detector detecting intensities of the first and second resonant lights passing through the atom; and a controller causing a frequency difference between specified first and second resonant lights to equal a frequency difference corresponding to an energy difference between two ground levels of the atom based on the detected light. The controller causes the frequency ?? or magnetic field intensity to satisfy 2×?×n=?? or ??×n=2×?. The frequency ? corresponds to an energy difference between two Zeeman split levels differentiated by one magnetic quantum number and generated in the two ground levels of the atom by energy splitting.
    Type: Application
    Filed: August 31, 2012
    Publication date: December 20, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Taku AOYAMA, Koji CHINDO
  • Publication number: 20120286885
    Abstract: A method of controlling an atomic oscillator includes generating a resonant light pair in response to a center frequency signal and a sideband signal, and setting the sideband signal so that an electromagnetically induced transparency (EIT) phenomenon does not occur in a gas cell of the atomic oscillator. The method includes applying the resonant light pair to the gas cell and detecting an intensity level of light transmitted through the gas cell. While the sideband signal is set so that the EIT phenomenon is not occurring, the center frequency signal is varied until a minimum value of the intensity level is identified. A first frequency is calculated by subtracting a predetermined frequency offset from the center frequency at which the intensity level was equal to the minimum value. A center frequency of the resonant light pair is set to the first frequency for operation of the atomic oscillator.
    Type: Application
    Filed: July 23, 2012
    Publication date: November 15, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Taku AOYAMA, Koji CHINDO
  • Publication number: 20120267509
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Application
    Filed: July 3, 2012
    Publication date: October 25, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Taku AOYAMA, Koji CHINDO
  • Patent number: 8279016
    Abstract: A quantum interference device causing electromagnetically induced transparency in an alkali metal atom includes: a light source generating first and second resonant lights with frequency differences ??; a magnetic field generator applying a magnetic field to the atom; a light detector detecting intensities of the first and second resonant lights passing through the atom; and a controller causing a frequency difference between specified first and second resonant lights to equal a frequency difference corresponding to an energy difference between two ground levels of the atom based on the detected light. The controller causes the frequency ?? or magnetic field intensity to satisfy 2×?×n=?? or ??×n=2×?. The frequency ? corresponds to an energy difference between two Zeeman split levels differentiated by one magnetic quantum number and generated in the two ground levels of the atom by energy splitting.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: October 2, 2012
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Patent number: 8253503
    Abstract: A method of controlling an atomic oscillator includes generating a resonant light pair in response to a center frequency signal and a sideband signal, and setting the sideband signal so that an electromagnetically induced transparency (EIT) phenomenon does not occur in a gas cell of the atomic oscillator. The method includes applying the resonant light pair to the gas cell and detecting an intensity level of light transmitted through the gas cell. While the sideband signal is set so that the EIT phenomenon is not occurring, the center frequency signal is varied until a minimum value of the intensity level is identified. A first frequency is calculated by subtracting a predetermined frequency offset from the center frequency at which the intensity level was equal to the minimum value. A center frequency of the resonant light pair is set to the first frequency for operation of the atomic oscillator.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: August 28, 2012
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Patent number: 8253497
    Abstract: An atomic oscillator, attention is paid to the fact that the degree of change of the energy difference between the two ground levels of the alkali metal atom with respect to the change of the magnetic field intensity is specific to each of the magnetic quantum numbers, a resonant light pair to cause a transition between the two ground levels corresponding to each of the plural magnetic quantum numbers is sequentially generated, plural pieces of profile information capable of specifying the energy difference between the two ground levels corresponding to each of the magnetic quantum numbers are sequentially acquired based on the detection signal, the change amount of the magnetic field intensity is specified based on the acquired plural pieces of profile information, and the control is performed so that the intensity of the magnetic field becomes constant.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: August 28, 2012
    Assignee: Seiko Epson Corporation
    Inventor: Taku Aoyama
  • Patent number: 8237514
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Grant
    Filed: February 3, 2010
    Date of Patent: August 7, 2012
    Assignee: Seiko Epson Corporation
    Inventors: Taku Aoyama, Koji Chindo
  • Publication number: 20120168604
    Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.
    Type: Application
    Filed: March 14, 2012
    Publication date: July 5, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Taku AOYAMA, Koji CHINDO
  • Publication number: 20120062327
    Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; heating units heating the gas cell to a predetermined temperature and being a first heater and a second heater; a light source of exciting light exciting the metal atom in the gas cell; a light detecting unit detecting the exciting light which has passed through the gas cell; a substrate including at least a temperature controlling circuit for the heating units; a first heater wiring coupling the first heater and the substrate; a second heater wiring coupling the second heater and the substrate; and a third heater wiring coupling the first heater and the second heater.
    Type: Application
    Filed: October 20, 2011
    Publication date: March 15, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Koji CHINDO, Taku AOYAMA
  • Patent number: 8067990
    Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; heating units heating the gas cell to a predetermined temperature and being a first heater and a second heater; a light source of exciting light exciting the metal atom in the gas cell; a light detecting unit detecting the exciting light which has passed through the gas cell; a substrate including at least a temperature controlling circuit for the heating units; a first heater wiring coupling the first heater and the substrate; a second heater wiring coupling the second heater and the substrate; and a third heater wiring coupling the first heater and the second heater. In the atomic oscillator, the gas cell includes a cylindrical portion; and windows which respectively seal openings at both ends of the cylindrical portion and constitute an incident surface and an emitting surface on an optical path of the exciting light.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: November 29, 2011
    Assignee: Seiko Epson Corporation
    Inventors: Koji Chindo, Taku Aoyama
  • Publication number: 20110260801
    Abstract: A physical section of an atomic oscillator includes: a gas cell in which gaseous metal atoms are sealed, and the gas cell includes a first window having optical transparency; a light source that emits excitation light toward the metal atoms through the first window; a first heating unit that disposes at the first window and that is located between the first window and the light source; and a Peltier element that is stacked on the first heating unit, that is located between the first heating unit and the light source, and that decreases a temperature of a side of the Peltier element facing the light source than a temperature of an opposite side of the Peltier element facing the gas cell.
    Type: Application
    Filed: July 7, 2011
    Publication date: October 27, 2011
    Applicant: EPSON TOYOCOM CORPORATION
    Inventors: Koji CHINDO, Taku AOYAMA
  • Publication number: 20110215878
    Abstract: An atomic oscillator, attention is paid to the fact that the degree of change of the energy difference between the two ground levels of the alkali metal atom with respect to the change of the magnetic field intensity is specific to each of the magnetic quantum numbers, a resonant light pair to cause a transition between the two ground levels corresponding to each of the plural magnetic quantum numbers is sequentially generated, plural pieces of profile information capable of specifying the energy difference between the two ground levels corresponding to each of the magnetic quantum numbers are sequentially acquired based on the detection signal, the change amount of the magnetic field intensity is specified based on the acquired plural pieces of profile information, and the control is performed so that the intensity of the magnetic field becomes constant.
    Type: Application
    Filed: March 1, 2011
    Publication date: September 8, 2011
    Applicant: Seiko Epson Corporation
    Inventor: Taku AOYAMA