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: 9671333Abstract: 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: GrantFiled: May 21, 2015Date of Patent: June 6, 2017Assignee: YOKOGAWA ELECTRIC CORPORATIONInventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
-
Patent number: 9347877Abstract: 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: GrantFiled: November 28, 2012Date of Patent: May 24, 2016Assignee: YOKOGAWA ELECTRIC CORPORATIONInventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
-
Publication number: 20150260646Abstract: 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: ApplicationFiled: May 21, 2015Publication date: September 17, 2015Applicant: YOKOGAWA ELECTRIC CORPORATIONInventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
-
Publication number: 20150185144Abstract: 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: ApplicationFiled: March 10, 2015Publication date: July 2, 2015Applicant: YOKOGAWA ELECTRIC CORPORATIONInventors: Takaaki Hirata, Yasuhiko Mitsumoto, Masaya Ooyama, Nobuhiko Kanbara, Naoyuki Fujimura, Minoru Maeda, Tadashi Sugiyama, Alan Cowie, Jie Zhu
-
Patent number: 7692796Abstract: 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: GrantFiled: August 5, 2008Date of Patent: April 6, 2010Assignee: Yokogawa Electric CorporationInventors: Takaaki Hirata, Minoru Maeda
-
Patent number: 7609386Abstract: 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: GrantFiled: November 24, 2008Date of Patent: October 27, 2009Assignee: Yokogawa Electric CorporationInventors: Takaaki Hirata, Minoru Maeda
-
Patent number: 7595886Abstract: 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: GrantFiled: June 23, 2006Date of Patent: September 29, 2009Assignee: Yokogawa Electric CorporationInventors: Takaaki Hirata, Minoru Maeda, Hironori Takai, Hiroki Saitou
-
Patent number: 7538885Abstract: 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: GrantFiled: May 31, 2006Date of Patent: May 26, 2009Assignee: Yokogawa Electric CorporationInventors: Takaaki Hirata, Minoru Maeda
-
Publication number: 20090079991Abstract: 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: ApplicationFiled: November 24, 2008Publication date: March 26, 2009Inventors: Takaaki HIRATA, Minoru MAEDA
-
Publication number: 20080316495Abstract: 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: ApplicationFiled: August 5, 2008Publication date: December 25, 2008Inventors: Takaaki HIRATA, Minoru Maeda
-
Publication number: 20060290937Abstract: 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: ApplicationFiled: June 23, 2006Publication date: December 28, 2006Inventors: Takaaki Hirata, Minoru Maeda, Hironori Takai, Hiroki Saitou
-
Publication number: 20060279741Abstract: 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: ApplicationFiled: May 31, 2006Publication date: December 14, 2006Inventors: Takaaki Hirata, Minoru Maeda
-
Patent number: 6738398Abstract: 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: GrantFiled: December 1, 2000Date of Patent: May 18, 2004Assignees: Yokogawa Electric Corporation, Matsushita Electric Industrial Co., Ltd.Inventors: Takaaki Hirata, Shinji Iio, Takeshi Inoue, Yasuo Kitaoka, Kazuhisa Yamamoto
-
Publication number: 20010005388Abstract: 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: ApplicationFiled: December 1, 2000Publication date: June 28, 2001Inventors: Takaaki Hirata, Shinji Iio, Takeshi Inoue, Yasuo Kitaoka, Kazuhisa Yamamoto
-
Patent number: 6008487Abstract: 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: GrantFiled: March 16, 1998Date of Patent: December 28, 1999Assignee: Yokogawa Electric CorporationInventors: Yoshihiko Tachikawa, Yoshihiro Sampei, Takaaki Hirata, Makoto Komiyama, Yasuyuki Suzuki, Mamoru Arihara
-
Patent number: 5844235Abstract: 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: GrantFiled: September 27, 1996Date of Patent: December 1, 1998Assignee: Yokogawa Electric CorporationInventors: Yoshihiko Tachikawa, Yoshihiro Sampei, Takaaki Hirata, Makoto Komiyama, Yasuyuki Suzuki, Mamoru Arihara
-
Patent number: 5145792Abstract: 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: GrantFiled: November 27, 1991Date of Patent: September 8, 1992Assignee: Optical Measurement Technology Development Co., Ltd.Inventor: Takaaki Hirata
-
Patent number: 4694250Abstract: 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: GrantFiled: February 24, 1986Date of Patent: September 15, 1987Assignee: Yokogawa Electric CorporationInventors: Hideto Iwaoka, Tadashi Sugiyama, Hiroyuki Matsuura, Takaaki Hirata