Patents by Inventor Toshiaki Kurahashi

Toshiaki Kurahashi 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).

  • Publication number: 20210324266
    Abstract: In one aspect of the present disclosure, there is provided an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains represented by formula X3Al5O12:Ce. In the optical wavelength conversion member 9, atoms of element X are present also in an Al2O3 crystal grain adjacent to the interface between the Al2O3 crystal grain and an X3Al5O12:Ce crystal grain.
    Type: Application
    Filed: July 17, 2019
    Publication date: October 21, 2021
    Inventors: Shohei TAKAKU, Yusuke KATSU, Tsuneyuki ITO, Toshiaki KURAHASHI, Hideto YAMADA
  • Publication number: 20210246367
    Abstract: One aspect of the disclosure provides an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains represented by formula (Y,A)3B5O12:Ce. In the optical wavelength conversion member, a (Y,A)3B5O12:Ce crystal grain has a region wherein the A concentration of a peripheral portion of the (Y,A)3B5O12:Ce crystal grain is higher than that of an interior portion of the (Y,A)3B5O12:Ce crystal grain. Thus, the optical wavelength conversion member exhibits high fluorescence intensity (i.e., high emission intensity) and high heat resistance (i.e., low likelihood of temperature quenching). The optical wavelength conversion member has a structure wherein the element A concentration of a peripheral portion of a (Y,A)3B5O12:Ce crystal grain differs from that in an interior portion of the crystal grain.
    Type: Application
    Filed: July 1, 2019
    Publication date: August 12, 2021
    Inventors: Shohei TAKAKU, Yusuke KATSU, Tsuneyuki ITO, Toshiaki KURAHASHI, Hideto YAMADA
  • Publication number: 20190241475
    Abstract: An object of the present disclosure is to improve the properties of a ceramic composition. A ceramic composition contains alumina (Al2O3) and tungsten carbide (WC) and is characterized in that an atomic layer formed of at least one element selected from among transition metals belonging to Groups 4 to 6 of the periodic table, yttrium (Y), scandium (Sc), and lanthanoids is present at a crystal grain boundary between an alumina (Al2O3) crystal grain and a tungsten carbide (WC) crystal grain.
    Type: Application
    Filed: September 20, 2017
    Publication date: August 8, 2019
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Yusuke KATSU, Toshiaki KURAHASHI, Hideto YAMADA, Takeshi MITSUOKA
  • Patent number: 10347817
    Abstract: A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase is 0.40<(Na/K)<3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the <100> direction with the main phase represented as a pseudo-cubic crystal system. Also, the area ratio of a crystal phase reflecting the second spots in the main phase is 33% or less, and the maximum grain size of crystals reflecting the second spots in the main phase is 25 nm or less.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: July 9, 2019
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Hisashi Kozuka, Hideto Yamada, Takayuki Matsuoka, Kazuaki Kitamura, Masato Yamazaki, Toshiaki Kurahashi, Takashi Kasashima, Yasuyuki Okimura, Kazushige Ohbayashi
  • Patent number: 10340441
    Abstract: A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide subphase. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase assumes a value in a range represented by 0.40<(Na/K)<3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the <100> direction with the main phase represented as a pseudo-cubic crystal system.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: July 2, 2019
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Hisashi Kozuka, Hideto Yamada, Takayuki Matsuoka, Kazuaki Kitamura, Masato Yamazaki, Toshiaki Kurahashi, Takashi Kasashima, Yasuyuki Okimura, Kazushige Ohbayashi
  • Patent number: 9938197
    Abstract: A lead-free piezoelectric ceramic composition includes a first crystal phase made of an alkali niobate/tantalate type perovskite oxide having piezoelectric properties, and a second crystal phase made of an M-Ti—O spinel compound (where the element M is a monovalent to quadrivalent element).
    Type: Grant
    Filed: March 11, 2014
    Date of Patent: April 10, 2018
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Masato Yamazaki, Takayuki Matsuoka, Kazuaki Kitamura, Hisashi Kozuka, Hideto Yamada, Toshiaki Kurahashi, Yasuyuki Okimura, Kazushige Ohbayashi, Takashi Kasashima
  • Patent number: 9871187
    Abstract: A lead-free piezo-electric porcelain composition which contains a main phase having voids and which is formed of a first crystal phase composed of an alkali niobate/tantalate-based perovskite oxide having piezo-electric characteristics; and a sub-phase containing a second crystal phase composed of an A2B6O13-based compound (where the element A is a monovalent element and the element B is one or more divalent to hexavalent elements). The sub-phase fills voids present in the main phase.
    Type: Grant
    Filed: April 9, 2015
    Date of Patent: January 16, 2018
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Masato Yamazaki, Takayuki Matsuoka, Yoshiteru Honda, Kazuaki Kitamura, Hisashi Kozuka, Toshiaki Kurahashi, Yasuyuki Okimura, Hideto Yamada, Kazushige Ohbayashi
  • Patent number: 9828296
    Abstract: A lead-free piezoelectric ceramic composition mainly includes a first crystal phase (KNN phase) and a second crystal phase (NTK phase). In the first crystal phase (KNN phase), a plurality of crystal grains formed of an alkali niobate/tantalate perovskite oxide having piezoelectric characteristics is bound to each other in a deposited state. The second crystal phase (NTK phase) is formed of a compound containing titanium (Ti) and fills spaces between the crystal grains in the first crystal phase.
    Type: Grant
    Filed: July 4, 2012
    Date of Patent: November 28, 2017
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Masato Yamazaki, Takayuki Matsuoka, Kazuaki Kitamura, Hideto Yamada, Toshiaki Kurahashi, Katsuya Yamagiwa, Kazushige Ohbayashi
  • Publication number: 20170141292
    Abstract: A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide subphase. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase assumes a value in a range represented by 0.40<(Na/K)<3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the <100> direction with the main phase represented as a pseudo-cubic crystal system.
    Type: Application
    Filed: March 5, 2015
    Publication date: May 18, 2017
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Hisashi KOZUKA, Hideto YAMADA, Takayuki MATSUOKA, Kazuaki KITAMURA, Masato YAMAZAKI, Toshiaki KURAHASHI, Takashi KASASHIMA, Yasuyuki OKIMURA, Kazushige OHBAYASHI
  • Publication number: 20170141293
    Abstract: A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase is 0.40<(Na/K)<3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the <100> direction with the main phase represented as a pseudo-cubic crystal system. Also, the area ratio of a crystal phase reflecting the second spots in the main phase is 33% or less, and the maximum grain size of crystals reflecting the second spots in the main phase is 25 nm or less.
    Type: Application
    Filed: March 5, 2015
    Publication date: May 18, 2017
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Hisashi KOZUKA, Hideto YAMADA, Takayuki MATSUOKA, Kazuaki KITAMURA, Masato YAMAZAKI, Toshiaki KURAHASHI, Takashi KASASHIMA, Yasuyuki OKIMURA, Kazushige OHBAYASHI
  • Publication number: 20160052826
    Abstract: A lead-free piezoelectric ceramic composition includes a first crystal phase made of an alkali niobate/tantalate type perovskite oxide having piezoelectric properties, and a second crystal phase made of an M-Ti—O spinel compound (where the element M is a monovalent to quadrivalent element).
    Type: Application
    Filed: March 11, 2014
    Publication date: February 25, 2016
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masato YAMAZAKI, Takayuki MATSUOKA, Kazuaki KITAMURA, Hisashi KOZUKA, Hideto YAMADA, Toshiaki KURAHASHI, Yasuyuki OKIMURA, Kazushige OHBAYASHI, Takashi KASASHIMA
  • Publication number: 20150295162
    Abstract: A lead-free piezo-electric porcelain composition which contains a main phase having voids and which is formed of a first crystal phase composed of an alkali niobate/tantalate-based perovskite oxide having piezo-electric characteristics; and a sub-phase containing a second crystal phase composed of an A2B6O13-based compound (where the element A is a monovalent element and the element B is one or more divalent to hexavalent elements). The sub-phase fills voids present in the main phase.
    Type: Application
    Filed: April 9, 2015
    Publication date: October 15, 2015
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masato YAMAZAKI, Takayuki MATSUOKA, Yoshiteru HONDA, Kazuaki KITAMURA, Hisashi KOZUKA, Toshiaki KURAHASHI, Yasuyuki OKIMURA, Hideto YAMADA, Kazushige OHBAYASHI
  • Publication number: 20140139070
    Abstract: A lead-free piezoelectric ceramic composition mainly includes a first crystal phase (KNN phase) and a second crystal phase (NTK phase). In the first crystal phase (KNN phase), a plurality of crystal grains formed of an alkali niobate/tantalate perovskite oxide having piezoelectric characteristics is bound to each other in a deposited state. The second crystal phase (NTK phase) is formed of a compound containing titanium (Ti) and fills spaces between the crystal grains in the first crystal phase.
    Type: Application
    Filed: July 4, 2012
    Publication date: May 22, 2014
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masato Yamazaki, Takayuki Matsuoka, Kazuaki Kitamura, Hideto Yamada, Toshiaki Kurahashi, Katsuya Yamagiwa, Kazushige Ohbayashi
  • Patent number: 8235606
    Abstract: A mirror unit that can decrease the wait time before distance measurement.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: August 7, 2012
    Assignee: Nikon Corporation
    Inventor: Toshiaki Kurahashi
  • Publication number: 20110236006
    Abstract: A mirror unit that can decrease the wait time before distance measurement.
    Type: Application
    Filed: June 10, 2011
    Publication date: September 29, 2011
    Applicant: NIKON CORPORATION
    Inventor: Toshiaki KURAHASHI
  • Publication number: 20100189428
    Abstract: Goal: Providing a mirror unit that can decrease the wait time before distance measurement.
    Type: Application
    Filed: January 25, 2010
    Publication date: July 29, 2010
    Applicant: NIKON CORPORATION
    Inventor: Toshiaki Kurahashi