Patents by Inventor Takaaki Hirata

Takaaki Hirata 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: 9671333
    Abstract: A laser gas analyzer includes a wavelength-variable laser having a wide wavelength-variable width, a light-split module configured to split an output light of the wavelength-variable laser into a measurement light and a reference light, a first gas cell into which gases to be measured are introduced, and the measurement light is made to be incident, and a data processor configured to obtain an absorption spectrum of each of the gases to be measured based on a reference signal related to the reference light and an absorption signal related to an output light of the first gas cell, and to obtain concentrations of the respective gases to be measured.
    Type: Grant
    Filed: May 21, 2015
    Date of Patent: June 6, 2017
    Assignee: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
  • Patent number: 9347877
    Abstract: A laser gas analyzer includes a wavelength-variable laser having a wide wavelength-variable width, a light-split module configured to split an output light of the wavelength-variable laser into a measurement light and a reference light, a first gas cell into which gases to be measured are introduced, and the measurement light is made to be incident, and a data processor configured to obtain an absorption spectrum of each of the gases to be measured based on a reference signal related to the reference light and an absorption signal related to an output light of the first gas cell, and to obtain concentrations of the respective gases to be measured.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: May 24, 2016
    Assignee: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
  • Publication number: 20150260646
    Abstract: A laser gas analyzer includes a wavelength-variable laser having a wide wavelength-variable width, a light-split module configured to split an output light of the wavelength-variable laser into a measurement light and a reference light, a first gas cell into which gases to be measured are introduced, and the measurement light is made to be incident, and a data processor configured to obtain an absorption spectrum of each of the gases to be measured based on a reference signal related to the reference light and an absorption signal related to an output light of the first gas cell, and to obtain concentrations of the respective gases to be measured.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 17, 2015
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
  • Publication number: 20150185144
    Abstract: A laser gas analyzer includes a wavelength-variable laser having a wide wavelength-variable width, a light-split module configured to split an output light of the wavelength-variable laser into a measurement light and a reference light, a first gas cell into which gases to be measured are introduced, and the measurement light is made to be incident, and a data processor configured to obtain an absorption spectrum of each of the gases to be measured based on a reference signal related to the reference light and an absorption signal related to an output light of the first gas cell, and to obtain concentrations of the respective gases to be measured.
    Type: Application
    Filed: March 10, 2015
    Publication date: July 2, 2015
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
  • Patent number: 7692796
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: April 6, 2010
    Assignee: Yokogawa Electric Corporation
    Inventors: Takaaki Hirata, Minoru Maeda
  • Patent number: 7609386
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Grant
    Filed: November 24, 2008
    Date of Patent: October 27, 2009
    Assignee: Yokogawa Electric Corporation
    Inventors: Takaaki Hirata, Minoru Maeda
  • Patent number: 7595886
    Abstract: A wavelength monitor includes the following elements. An optical divider divides a beam of measured light into first and second divided beams of measured light. An interfering element converts the first and second divided beams of measured light into first and second parallel beams of measured light to cause interference between the first and second parallel beams of measured light with each other thereby generating an interfered beam of measured light. A light receiving element way including a plurality of light receiving elements receives the interfered beam of measured light. An interference signal converting unit receives output signals from the light receiving element array to generate interference signals different in phase by 90 degrees from each other. A signal processing unit receives the interference signals from the interference signal converting unit to obtain a wavelength of the measured light from the interference signals.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: September 29, 2009
    Assignee: Yokogawa Electric Corporation
    Inventors: Takaaki Hirata, Minoru Maeda, Hironori Takai, Hiroki Saitou
  • Patent number: 7538885
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: May 26, 2009
    Assignee: Yokogawa Electric Corporation
    Inventors: Takaaki Hirata, Minoru Maeda
  • Publication number: 20090079991
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Application
    Filed: November 24, 2008
    Publication date: March 26, 2009
    Inventors: Takaaki HIRATA, Minoru MAEDA
  • Publication number: 20080316495
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Application
    Filed: August 5, 2008
    Publication date: December 25, 2008
    Inventors: Takaaki HIRATA, Minoru Maeda
  • Publication number: 20060290937
    Abstract: A wavelength monitor includes the following elements. An optical divider divides a beam of measured light into first and second divided beams of meal light. An interfering element converts the first and second divided beams of measured light into first and second parallel beams of measured light to cause interference between the first and second parallel beams of measured light with each other thereby generating an interfered beam of measured light. A light receiving element way including a plurality of light receiving elements receives the interfered beam of measured light. An interference signal converting unit receives output signals from the light receiving element array to generate interference signals different in phase by 90 degrees from each other. A signal processing unit receives the interference signals from the interference signal converting unit to obtain a wavelength of the measured light from the interference signals.
    Type: Application
    Filed: June 23, 2006
    Publication date: December 28, 2006
    Inventors: Takaaki Hirata, Minoru Maeda, Hironori Takai, Hiroki Saitou
  • Publication number: 20060279741
    Abstract: An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
    Type: Application
    Filed: May 31, 2006
    Publication date: December 14, 2006
    Inventors: Takaaki Hirata, Minoru Maeda
  • Patent number: 6738398
    Abstract: The invention provides an SHG laser light source whose optical output can be modulated using a simple mechanism without having to equip the light source with an external modulator, and a method of modulation for use with the SHG laser light source, wherein the SHG laser light source comprises a laser diode for outputting a fundamental wave of light, a drive circuit for simultaneously modulating one or more electric currents or voltages supplied to the laser diode to modulate the fundamental wave outputted by the laser diode, and an SHG device which receives the modulated or unmodulated fundamental wave, converts the wavelength thereof, and outputs a second harmonic wave which is intensity modulated.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: May 18, 2004
    Assignees: Yokogawa Electric Corporation, Matsushita Electric Industrial Co., Ltd.
    Inventors: Takaaki Hirata, Shinji Iio, Takeshi Inoue, Yasuo Kitaoka, Kazuhisa Yamamoto
  • Publication number: 20010005388
    Abstract: The invention provides an SHG laser light source whose optical output can be modulated using a simple mechanism without having to equip the light source with an external modulator, and a method of modulation for use with the SHG laser light source, wherein the SHG laser light source comprises a laser diode for outputting a fundamental wave of light, a drive circuit for simultaneously modulating one or more electric currents or voltages supplied to the laser diode to modulate the fundamental wave outputted by the laser diode, and an SHG device which receives the modulated or unmodulated fundamental wave, converts the wavelength thereof, and outputs a second harmonic wave which is intensity modulated.
    Type: Application
    Filed: December 1, 2000
    Publication date: June 28, 2001
    Inventors: Takaaki Hirata, Shinji Iio, Takeshi Inoue, Yasuo Kitaoka, Kazuhisa Yamamoto
  • Patent number: 6008487
    Abstract: In the primary invention of this application, an optical-fiber inspection device which detects the distance to a reflection point within the DUT and the amount of reflected light by dividing into two a laser beam which is possible to be frequency-swept, making one of the divided light beams incident to an optical detector via the reference light path, while making the other of the divided light beams incident to the DUT and making the light reflected within the DUT incident to the said optical detector, and analyzing the frequency of the interference signal for the two beams obtained by the optical detector, is configured so that the final reference light is obtained by providing an optical coupler in the reference light path and, after taking out a part of the reference light and making it pass through an optical frequency shifter, combining this again with the original reference light with the said optical coupler.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: December 28, 1999
    Assignee: Yokogawa Electric Corporation
    Inventors: Yoshihiko Tachikawa, Yoshihiro Sampei, Takaaki Hirata, Makoto Komiyama, Yasuyuki Suzuki, Mamoru Arihara
  • Patent number: 5844235
    Abstract: In the primary invention of this application, an optical-fiber inspection device which detects the distance to a reflection point within the DUT and the amount of reflected light by dividing into two a laser beam which is possible to be frequency-swept, making one of the divided light beams incident to an optical detector via the reference light path, while making the other of the divided light beams incident to the DUT and making the light reflected within the DUT incident to the said optical detector, and analyzing the frequency of the interference signal for the two beams obtained by the optical detector, is configured so that the final reference light is obtained by providing an optical coupler in the reference light path and, after taking out a part of the reference light and making it pass through an optical frequency shifter, combining this again with the original reference light with the said optical coupler.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: December 1, 1998
    Assignee: Yokogawa Electric Corporation
    Inventors: Yoshihiko Tachikawa, Yoshihiro Sampei, Takaaki Hirata, Makoto Komiyama, Yasuyuki Suzuki, Mamoru Arihara
  • Patent number: 5145792
    Abstract: A semiconductor optical device having a quantum well structure which can easily integrate plural optical devices of band gaps which are different from each other, and yet can achieve a high coupling coefficient by means of disordering the quantum well structure to form a waveguide region except for the portion which is used as an active region. Non-absorbing edges can be formed on the semiconductor laser on the optically integrated circuits by disordering the facets of the quantum well structure with ion implantation and thermal processing.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: September 8, 1992
    Assignee: Optical Measurement Technology Development Co., Ltd.
    Inventor: Takaaki Hirata
  • Patent number: 4694250
    Abstract: In a nuclear magnetic resonance imaging device, a pulse sequence is selected and a variance or standard deviation of a calculated image for T1, T2, .rho. is determined as a function of scan parameters from the theoretical equation of signal intensity in the pulse sequence and the variance in the values for T1, T2, .rho. to be measured and the original image. Scan parameters, with which the total sum of variance or standard deviation of the calculated image takes a minimum value, are determined as optimum values. An image is obtained from the optimum scan parameters to obtain a plurality of original images. A calculated image for T1, T2, .rho. is determined, based on the original images, whereby a calculated image of high quality is simultaneously obtained.
    Type: Grant
    Filed: February 24, 1986
    Date of Patent: September 15, 1987
    Assignee: Yokogawa Electric Corporation
    Inventors: Hideto Iwaoka, Tadashi Sugiyama, Hiroyuki Matsuura, Takaaki Hirata