Patents by Inventor Tsuguo Fukuda

Tsuguo Fukuda 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: 7323053
    Abstract: It is an object of the present invention to provide a pulling-down apparatus that can breed a crystal having good characteristics of scintillation. The apparatus retains in a container that can control an atmosphere a melting pot having a narrow hole at the bottom side thereof, an induction heating device, and a seed-holding device that holds a seed and is pulled down so that a crystal formed successively to the seed is pulled down. Concurrently, imaging devices are arranged that can pick up images of a solid-liquid interface between the crystal and a melt material, from different directions, and the seed-holding device can be travel along directions perpendicular to respective image pickup directions in a horizontal plane.
    Type: Grant
    Filed: January 23, 2006
    Date of Patent: January 29, 2008
    Assignee: TDK Corporation
    Inventors: Kazushige Tohta, Kou Onodera, Takeshi Ito, Tsuguo Fukuda, Akira Yoshikawa
  • Publication number: 20080008438
    Abstract: It is an object of the present invention to provide a self-coated single crystal that without any special step conducted after crystal growth, has its circumference coated with a layer of different properties. A self-coated single crystal according to the present invention is characterized in that in operations comprising melting crystal materials for a core and a clad in a single crucible and carrying out growth of a single crystal through a pulling up method or a pulling down method, a grown single crystal in an as-growth condition has its circumference self-coated with a clad whose refractive index is lower than that of the core.
    Type: Application
    Filed: April 11, 2005
    Publication date: January 10, 2008
    Applicant: TOHOKU TECHNO ARCH CO., LTD.
    Inventors: Tsuguo Fukuda, Akira Yoshikawa, Yuji Kagamitani
  • Publication number: 20070272898
    Abstract: A rare earth fluoride solid solution material (polycrystal and/or single crystal) characterized in that the material is obtained by mutually combining a plurality of rare earth fluorides having phase transitions and having different ion radii, respectively, so that the rare earth fluoride solid solution material is free of phase transitions. A rare earth fluoride solid solution material (polycrystal and/or single crystal) characterized in that the material is represented by (REyRE?1-y)F3 (0.0000<y<1.0000), wherein RE represents one or two or more selected from Sm, Eu, and Gd, and RE? represents one or two or more selected from Er, Tm, Yb, Lu, and Y. A rare earth fluoride solid solution material (polycrystal and/or single crystal) represented by MxREyRE?1-x-yFz, wherein RE is one or two or more selected from Ce, Pr, Nd, Eu, Tb, Ho, Er, Tm, or Yb, RE? is one or two or more selected from La, Sm, Gd, Dy, Lu, Y, and Sc, and M is one or more of Mg, Ca, Sr, and Ba.
    Type: Application
    Filed: April 12, 2005
    Publication date: November 29, 2007
    Inventors: Akira Yoshikawa, Kenji Aoki, Tomohiko Satonaga, Kei Kamada, Tsuguo Fukuda
  • Publication number: 20070193499
    Abstract: To find out a crystalline material for a high speed scintillator in place of BaF2 and the like, and a method for producing the material at a low cost. A single crystal of (Zn1?xMx)O1+x (M: Al, Ga, In, Y, Sc, La, Gd, Lu) (x=0 to 0.0500), (Zn1?xM?x)O1+2x(M?: Si, Ge, Sn, Pb)(x=0 to 0.0250) or (Zn1?xCdx)O (x=0 to 0.0500) is used as a scintillator. Defects of a ZnO single crystal can be reduced by using a platinum inner cylinder in order for a solution not to directly contact with an autoclave, for reducing impurities in the ZnO single crystal and precluding impurities interfering with scintillation, and by using LiOH and KOH as a mineralizer. ZnO can be doped with Al2O3, Ga2O3, In2O3, Si, Cd or the like by adding those materials to a starting material for the hydrothermal synthesis. The doping amounts can be controlled by changing charging amounts thereof.
    Type: Application
    Filed: May 20, 2005
    Publication date: August 23, 2007
    Inventors: Tsuguo Fukuda, Akira Yoshikawa, Hiraku Ogino
  • Publication number: 20070175383
    Abstract: [Problems] To provide a process that allows melt growth of single crystals of a gallium-containing nitride with less dangerous, inexpensive equipment, in particular, a process that can be performed under normal pressure.
    Type: Application
    Filed: January 20, 2005
    Publication date: August 2, 2007
    Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Tsuguo Fukuda, Ehrentraut Dirk, Akira Yoshikawa
  • Publication number: 20070095273
    Abstract: It is aimed at providing a fluoride crystal growing method capable of controlling a shape of the crystal by a micro-pulling-down method. Fluoride crystals in shapes depending on purposes, respectively, can be grown by adopting carbon, platinum, and iridium as crucible materials adaptable to fluorides, respectively, and by designing shapes of the crucibles taking account of wettabilities of the materials with the fluorides, respectively.
    Type: Application
    Filed: July 20, 2004
    Publication date: May 3, 2007
    Inventors: Tomohiko Satonaga, Hirohisa Kikuyama, Tsuguo Fukuda
  • Publication number: 20070056508
    Abstract: An apparatus for producing a fluoride crystal, which has a chamber, a window material and the like capable of dealing with the fluoride, is equipped with facilities necessary for high vacuum evacuation, and uses a crucible in which the capillary portion of the hole formed in the bottom thereof is so controlled for a seed crystal and a molten material to be easily contacted to each other; and a method for producing a fluoride crystal comprising using the apparatus. The apparatus allows the production of a single crystal of a fluoride having high quality in a extremely short time with stability.
    Type: Application
    Filed: April 23, 2004
    Publication date: March 15, 2007
    Inventors: Tsuguo Fukuda, Hirohisa Kikuyama, Tomohiko Satonaga
  • Publication number: 20070034139
    Abstract: It is aimed at providing an analysis method of impurities (color centers) in fluoride, capable of extremely simply analyzing impurities (color centers) in fluoride. It is also aimed at providing an analysis method of impurities (color centers) in fluoride, for enabling evaluation of an effect by addition of a scavenger, before obtainment of a final single crystal. There are detected absorption peaks and the like of formed color centers and the like, by irradiating X-rays to an obtained fused material, and by measuring transmittances thereof before and after the irradiation. Based thereon, there are optimized melt conditions of a scavenger and the like, thereby enabling growth of a high purity molten raw material suitable for growth of a single crystal less in X-ray damage.
    Type: Application
    Filed: March 4, 2004
    Publication date: February 15, 2007
    Inventors: Tsuguo Fukuda, Hirohisa Kikuyama, Tomohiko Satonaga, Kazuhiko Shogami
  • Publication number: 20070018107
    Abstract: A scintillator, characterized in that it comprises crystals of Pr1-xCexF3 [wherein 0<x<0.5]. It emits a light in ultraviolet and visible regions when it is irradiated with a light or a radiation. The scintillator uses a material which exhibits improved performance with respect to the strength in light emission and to the speed in attenuation, and further is relatively easy in the growth of its crystal.
    Type: Application
    Filed: August 25, 2004
    Publication date: January 25, 2007
    Inventors: Tsuguo Fukuda, Hirohisa Kikuyama, Tomohiko Satonaga, Hikaru Koike
  • Publication number: 20060279836
    Abstract: A last lens for immersion lithography exposure equipment, composed of a crystal represented by formula BaLiF3. The crystal is preferably a single crystal represented by formula BaLiF3. The immersion lithography exposure equipment preferably comprises a light source which emits light with a wavelength of not more than 200 nm. More specifically, the immersion lithography exposure equipment preferably comprises an ArF excimer laser oscillator or an F2 excimer laser oscillator. In the last lens for the immersion lithography exposure equipment, at the wavelength of light used in a light source, preferably at a wavelength of not more than 200 nm, a high refractive index, a high transmission, and low SBR can be realized, and the resolution of the exposure equipment can easily be improved.
    Type: Application
    Filed: May 25, 2006
    Publication date: December 14, 2006
    Applicant: Tokuyama Corporation
    Inventors: Teruhiko Nawata, Yoji Inui, Eiichi Nishijima, Tsuguo Fukuda
  • Publication number: 20060185580
    Abstract: It is an object of the present invention to provide a pulling-down apparatus that can breed a crystal having good characteristics of scintillation. The apparatus retains in a container that can control an atmosphere a melting pot having a narrow hole at the bottom side thereof, an induction heating device, and a seed-holding device that holds a seed and is pulled down so that a crystal formed successively to the seed is pulled down. Concurrently, imaging devices are arranged that can pick up images of a solid-liquid interface between the crystal and a melt material, from different directions, and the seed-holding device can be travel along directions perpendicular to respective image pickup directions in a horizontal plane.
    Type: Application
    Filed: January 23, 2006
    Publication date: August 24, 2006
    Applicant: TDK Corporation
    Inventors: Kazushige Tohta, Kou Onodera, Takeshi Ito, Tsuguo Fukuda, Akira Yoshikawa
  • Publication number: 20050161638
    Abstract: Disclosed is a luminescent material for scintillators, which comprises a single crystal of an Yb-containing mixed-crystal oxide having a base crystal consisting of a garnet single crystal or a borate single crystal. The oxide single crystal has a composition represented by either one selected from the group consisting of R3Al5O12, R3Ga5O12, Li6R(BO3)3, LaR2Ga3O12 and Gd3R2Ga3O12, wherein R is a mixture of Yb and either one of Y, Gd and Lu. The Yb as an element capable of forming an optically active state called CTS together with a neighboring negative ion (oxygen ion).
    Type: Application
    Filed: March 25, 2003
    Publication date: July 28, 2005
    Inventors: Tsuguo Fukuda, Akira Yoshikawa, Takashi Tsuzaki
  • Publication number: 20040107893
    Abstract: The single crystal of alkaline earth metal fluoride of the invention is produced by a single crystal pulling method, has a straight barrel part diameter of not less than 17 cm, preferably has a straight barrel part length of not less than 5 cm, and has a light transmittance, as measured at a wavelength of 632.8 nm, of not less than 80%, preferably 90 to 98%. Further, the main crystal growth plane of the single crystal of the invention is the {111}plane or the {100}plane. The single crystal of alkaline earth metal fluoride of the invention has a large diameter as described above, and in spite that it is in an as-grown state, the peripheral surface is not opaque and the visible light transmittance is high. Therefore, evaluation of bubbles or inclusions in the crystal becomes feasible without performing complicated machining of the crystal, and from the single crystal, a large-sized optical material having advantageous properties such as high quality and high uniformity can be cut out.
    Type: Application
    Filed: November 19, 2003
    Publication date: June 10, 2004
    Applicant: TOKUYAMA CORPORATION
    Inventors: Teruhiko Nawata, Nobuyuki Kuramoto, Hiroyuki Yanagi, Tsuguo Fukuda
  • Publication number: 20040099207
    Abstract: The object of the present invention is to provide an as-grown single crystal of calcium fluoride having a large diameter and small birefringence. The as-grown single crystal of calcium fluoride according to the present invention is obtained by a single crystal pulling method (Czochralski method), has a straight barrel part diameter of 17 cm or more, preferably has a straight barrel part length of 50 mm or more, and has a birefringence of not more than 3 nm/cm, preferably 0.1 to 2.0 nm/cm.
    Type: Application
    Filed: November 19, 2003
    Publication date: May 27, 2004
    Applicant: TOKUYAMA CORPORATION
    Inventors: Teruhiko Nawata, Nobuyuki Kuramoto, Hiroyuki Yanagi, Tsuguo Fukuda
  • Patent number: 6400061
    Abstract: The present invention provides a piezoelectric substrate for a surface acoustic wave device which has high electromechanical coupling coefficient and low SAW velocity, and a surface acoustic wave device using the same. The present invention applies a single crystal comprising belonging to a point group 32 and having Ca3Ga2Ge4O14 type crystal structure. The basic component of the single crystal is comprised of La, Sr, Ta, Ga and O and is represented by the chemical formula: La3−xSrxTa0.5+0.5xGa5.5−0.5xO14. The composition ratio of Sr is preferably in the range of 0 x≦0.15, and more preferably in the range of 0.07 x≦0.08. The present invention also provides a surface acoustic wave device using that in which an interdigital finger electrode is formed in one main surface of the aforementioned piezoelectric substrate.
    Type: Grant
    Filed: May 19, 2000
    Date of Patent: June 4, 2002
    Assignee: TDK Corporation
    Inventors: Kenji Inoue, Tsuguo Fukuda, Katsuo Sato, Hiroki Morikoshi, Katsumi Kawasaki, Kiyoshi Uchida
  • Patent number: 6303048
    Abstract: A melt containing lanthanum oxide, tantalum oxide, and gallium oxide is prepared by mixing the powders of these oxides so as to have a stoichiometric composition ratio of an intended lanthanum/tantalum/gallium oxide to be manufactured. A crystal is pulled up from the melt in an atmosphere containing argon and oxygen according to the Czochralski process. The concentration of the oxygen is in a range from 0.1 vol % to 1.5 vol % with respect to the concentration of the argon.
    Type: Grant
    Filed: March 16, 1999
    Date of Patent: October 16, 2001
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Hiroyuki Kawanaka, Tsuguo Fukuda
  • Patent number: 6180872
    Abstract: A process for growing a crystalline silicon plate, including the steps of arranging a planar growth member and a growth crucible in which a melt of silicon is placed and which is provided with a melt draw-out opening at a lower side thereof, while at least a tip portion of the growth member is located under the draw-out opening, drawing out the melt from the crucible through the draw-out opening, bringing the drawn out melt into contact with the tip portion of the growth member, and further pulling down the melt through the tip portion of the growth member.
    Type: Grant
    Filed: March 17, 2000
    Date of Patent: January 30, 2001
    Assignee: NGK Insulators, Ltd.
    Inventors: Tsuguo Fukuda, Minoru Imaeda, Yuichiro Imanishi
  • Patent number: 6074477
    Abstract: A process is disclosed for producing an integrated composite oxide single crystal body composed of a core portion made of an oxide single crystal and a clad portion integrated with the core portion and made of another oxide single crystal having a composition different from that of the oxide single crystal constituting the core portion, the process comprising the steps of: (1) preparing a first melt in a first crucible by melting a first material for a first oxide single crystal to constitute the core portion inside the first crucible, (2) preparing a second melt inside a second crucible by melting a second material for a second oxide single crystal to constitute the clad portion inside the second crucible, (3) contacting a seed crystal to the first and second melts, (4) pulling down the first melt through a pull-out opening of the first crucible, (5) pulling down the second melt through a pull-out opening of the second crucible and contacting the pulled-down second melt with a pulled-down portion of the firs
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: June 13, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Tsuguo Fukuda, Kiyoshi Shimamura, Tatsuo Kawaguchi
  • Patent number: 6072118
    Abstract: A process for growing a crystalline silicon plate, including the steps of arranging a planar growth member and a growth crucible in which a melt of silicon is placed and which is provided with a melt draw-out opening at a lower side thereof, while at least a tip portion of the growth member is located under the draw-out opening, drawing out the melt from the crucible through the draw-out opening, bringing the drawn out melt into contact with the tip portion of the growth member, and further pulling down the melt through the tip portion of the growth member.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: June 6, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Tsuguo Fukuda, Minoru Imaeda, Yuichiro Imanishi
  • Patent number: 6030449
    Abstract: A garnet crystal for growing a substrate is used in manufacturing a magneto-optic element. The garnet is manufactured by a Czochralski method and has a chemical structure represented by La.sub.8-(x+y) Yb.sub.x Ga.sub.y O.sub.12 wherein x has the range 1.0.ltoreq.x.ltoreq.3.0, y has the range 2.5.ltoreq.y.ltoreq.4.5, and (x+y) has the range 5.0.ltoreq.(x+y).ltoreq.6.5. The garnet crystal is grown from a melt prepared by heating a mixture of gadolinium oxide, ytterbium oxide, and gallium oxide in a crucible, the oxides being mixed together in a weight proportion such that the atomic proportion is La:Yb:Ga=3:p:q wherein p has the range 1.0.ltoreq.p.ltoreq.3.0 and q has the range 2.0.ltoreq.q.ltoreq.4.5.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: February 29, 2000
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Tsuguo Fukuda, Norio Takeda