Patents by Inventor Yutaka Kuroiwa

Yutaka Kuroiwa 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: 20120153806
    Abstract: An electrode for a discharge lamp is provided with a mayenite compound in at least a part of the electrode that emits secondary electrons, and a surface of a surface layer of the mayenite compound is plasma treated.
    Type: Application
    Filed: February 24, 2012
    Publication date: June 21, 2012
    Applicant: Asahi Glass Company, Limited
    Inventors: Kazuhiro Ito, Satoru Watanabe, Naomichi Miyakawa, Yutaka Kuroiwa, Setsuro Ito
  • Publication number: 20120153805
    Abstract: An electrode for a discharge lamp includes an electrode body configured to emit thermal electrons. The electrode body is formed by a sintered body of a conductive mayenite compound.
    Type: Application
    Filed: February 23, 2012
    Publication date: June 21, 2012
    Applicant: Asahi Glass Company, Limited
    Inventors: Satoru WATANABE, Naomichi MIYAKAWA, Yutaka KUROIWA, Kazuhiro ITO, Setsuro ITO, Kei MAEDA
  • Publication number: 20120153807
    Abstract: An electrode for a fluorescent lamp includes a filament and an emitter provided on the filament. The emitter includes a mayenite compound.
    Type: Application
    Filed: February 24, 2012
    Publication date: June 21, 2012
    Applicant: Asahi Glass Company, Limited
    Inventors: Shigeo Mikoshiba, Satoru Watanabe, Kazuhiro Ito, Naomichi Miyakawa, Setsuro Ito, Kei Maeda, Yutaka Kuroiwa
  • Publication number: 20120131955
    Abstract: The present invention relates to a method for manufacturing an ultra-thin glass substrate, the method including: a feeding step of feeding a preform for a glass substrate to a production line while being held; a heating step of heating the preform fed from the feeding step to a temperature around a softening point thereof; and a drawing step of drawing the preform that has softened in the heating step to form an ultra-thin glass substrate, in which the preform has been wound on a cylindrical first winding roll.
    Type: Application
    Filed: February 6, 2012
    Publication date: May 31, 2012
    Inventors: Yutaka Kuroiwa, Seiki Ohara
  • Patent number: 8109118
    Abstract: It is an object of the present invention to provide a method and apparatus for efficiently remove bubbles present on a surface of molten glass, which can solve a problem that bubbles remaining on a surface of molten glass are get inside at a time of forming the glass to cause inside bubbles, to thereby provide a glass substrate of good quality, and which can improve productivity of glass substrates; and to provide a process for producing glass employing the above method for removing bubbles. The present invention provides a method for removing bubbles from molten glass, which is a method for removing floating bubbles on a surface of molten glass, wherein a floating bubble on the surface of molten glass is irradiated with at least one laser beam.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: February 7, 2012
    Assignee: Asahi Glass Company, Limited
    Inventors: Mitsuru Watanabe, Yutaka Kuroiwa, Motoichi Iga, Setsuro Ito, Yasuji Fukasawa
  • Publication number: 20090113938
    Abstract: It is an object of the present invention to provide a method and apparatus for efficiently remove bubbles present on a surface of molten glass, which can solve a problem that bubbles remaining on a surface of molten glass are get inside at a time of forming the glass to cause inside bubbles, to thereby provide a glass substrate of good quality, and which can improve productivity of glass substrates; and to provide a process for producing glass employing the above method for removing bubbles. The present invention provides a method for removing bubbles from molten glass, which is a method for removing floating bubbles on a surface of molten glass, wherein a floating bubble on the surface of molten glass is irradiated with at least one laser beam.
    Type: Application
    Filed: November 6, 2008
    Publication date: May 7, 2009
    Applicant: Asahi Glass Company, Limited
    Inventors: Mitsuru Watanabe, Yutaka Kuroiwa, Motoichi Iga, Setsuro Ito, Yasuji Fukasawa
  • Publication number: 20080252194
    Abstract: To provide an electron emitter, a field emission display unit, a cold cathode fluorescent tube and a flat type lighting device, which employ an electron emitting material producible at a low cost and in a large amount. A conductive mayenite type compound powder containing at least 50 mol % of a mayenite type compound represented by a chemical formula of either 12CaO.7Al2O3 or 12SrO.7Al2O3 and having a maximum particle size of at most 100 ?m, is used as an electron emitter, whereby an electron emitter, a field emission display unit, a cold cathode fluorescent tube and a flat type lighting device, are realized that are easy to produce and capable of emitting electrons even at a low applied voltage and whereby a large current can be obtained per the same applied voltage surface.
    Type: Application
    Filed: October 18, 2007
    Publication date: October 16, 2008
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Yutaka KUROIWA, Satoru Narushima, Setsuro Ito
  • Publication number: 20080037014
    Abstract: It is an object of the present invention to provide a new method for reducing the diameter of a bubble existing in a glass plate. Specifically, the present invention provides a method for reducing the diameter of a bubble existing in a glass plate, which comprises irradiating the vicinity of the bubble existing in the glass plate with a light beam emitted from a light source, to raise the temperature of the glass in the vicinity of the bubble to at least the melting point of the glass to reduce the maximum diameter of the bubble.
    Type: Application
    Filed: October 15, 2007
    Publication date: February 14, 2008
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Yutaka KUROIWA, Setsuro Ito, Motoichi Iga
  • Patent number: 6620748
    Abstract: An optical amplifying glass comprising a matrix glass and, added thereto, from 0.01 to 10 wt % of Er, characterized in that said matrix glass substantially comprises, as represented by mol %, 20 to 80 of Bi2O3, 0 to 74.89 of B2O3, 0 to 79.99 of SiO2, 0.01 to 10 of CeO2, 0 to 50 of Li2O, 0 to 50 of TiO2, 0 to 50 of ZrO2, 0 to 50 of SnO2, 0 to 30 of WO3, 0 to 30 of TeO2, 0 to 30 of Ga2O3 and 0 to 10 of Al2O3, with the proviso that said matrix glass contains at least one of B2O3 and SiO2.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: September 16, 2003
    Inventors: Naoki Sugimoto, Yutaka Kuroiwa, Setsuro Ito, Setsuhisa Tanabe, Teiichi Hanada
  • Patent number: 6560392
    Abstract: An optical amplifying glass fiber comprising a core glass and a clad glass, wherein a relation of: 0.0005≦(n1−n2)/n1≦0.1 where n1 and n2 are refractive indices of the core glass and the clad glass, respectively, is satisfied, the fiber has a length of at most 25 cm, the core glass contains Er, and the wavelength width wherein a gain is obtainable with light having a wavelength of from 1.50 to 1.59 &mgr;m, is at least 30 nm.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: May 6, 2003
    Assignee: Asahi Glass Company, Limited
    Inventors: Naoki Sugimoto, Yutaka Kuroiwa, Setsuro Ito
  • Publication number: 20030007759
    Abstract: An optical amplifying glass fiber comprising a core glass and a clad glass, wherein a relation of:
    Type: Application
    Filed: April 24, 2001
    Publication date: January 9, 2003
    Applicant: Asahi Glass Company, Limited
    Inventors: Naoki Sugimoto, Yutaka Kuroiwa, Setsuro Ito
  • Publication number: 20010047668
    Abstract: A method for connecting two glass fibers, which comprises abutting the end surfaces to be connected of the two glass fibers so that their axes are in a line, and raising the temperature at the abutted end surfaces so that the end surfaces are fusion-spliced to connect the two glass fibers, wherein one of the two glass fibers is a high-melting glass fiber having a higher glass transition point and the other is a low-melting glass fiber having a lower glass transition point, and the heating is carried out in such a manner that the temperature is highest at a portion on the high-melting glass fiber distant by at least 1 &mgr;m from the end surface to raise the temperature at the end surfaces.
    Type: Application
    Filed: May 22, 2001
    Publication date: December 6, 2001
    Applicant: Asahi Glass Company, Limited
    Inventors: Katsuhiro Ochiai, Yutaka Kuroiwa, Naoki Sugimoto, Takeshi Hirose