Patents by Inventor Kazuhiro Ouchi

Kazuhiro Ouchi 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: 7339764
    Abstract: A method of designing a patterned magnetic recording medium including a magnetic film with perpendicular magnetic anisotropy which is patterned into dots form includes steps of setting values to dot pattern periods Px and Py, a thickness “t”, a thermal stability factor Kn, a minimum inter-dot spacing S0, and a maximum recording field Hm, setting an initial value of a saturation magnetization Ms, finding a nucleation field for magnetization reversal Hn and estimating a coercivity Hc and a saturation field Hs, and repeating the steps given above so as to make the saturation field Hs lower than the maximum recording field Hm, thereby determining the magnetic properties Ms, Hn and Hc satisfying a desired condition.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: March 4, 2008
    Assignees: Japan Science and Technology Agency, Akita Prefecture
    Inventors: Naoki Honda, Kazuhiro Ouchi
  • Publication number: 20070159721
    Abstract: A method of designing a patterned magnetic recording medium including a magnetic film with perpendicular magnetic anisotropy which is patterned into dots form includes steps of setting values to dot pattern periods Px and Py, a thickness “t”, a thermal stability factor Kn, a minimum inter-dot spacing S0, and a maximum recording field Hm, setting an initial value of a saturation magnetization Ms, finding a nucleation field for magnetization reversal Hn and estimating a coercivity Hc and a saturation field Hs, and repeating the steps given above so as to make the saturation field Hs lower than the maximum recording field Hm, thereby determining the magnetic properties is Ms. Hn and Hc satisfying a desired condition.
    Type: Application
    Filed: March 22, 2007
    Publication date: July 12, 2007
    Inventors: Naoki Honda, Kazuhiro Ouchi
  • Publication number: 20040166369
    Abstract: A high saturation flux density soft magnetic film substantially consists of an FexCo1-x alloy (0.65≦x≦0.75) containing 3% or less of Al2O3.
    Type: Application
    Filed: February 27, 2004
    Publication date: August 26, 2004
    Applicant: Akita Prefecture
    Inventors: Kazuhiko Shintaku, Kiyoshi Yamakawa, Kazuhiro Ouchi
  • Patent number: 6641934
    Abstract: To present an information recording medium for achieving high density information recording, in particular, a high signal output and a high resolution in magnetic recording, for example, an information recording medium sequentially forming a layer made of soft magnetic material, a layer made of nonmagnetic material, and an information recording layer of ordered alloy with L10 crystal structure selected from group A is manufactured in a specified manufacturing method. Herein the group A is defined to include FePt ordered alloy, CoPt ordered alloy, FePd ordered alloy, and their alloy.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: November 4, 2003
    Assignee: Governor of Akita Prefecture
    Inventors: Toshio Suzuki, Naoki Honda, Kazuhiro Ouchi
  • Patent number: 6599646
    Abstract: An information recording layer consisting of a composite of an ordered alloy of L10 crystal structure selected from a group A, and MgO is used for a perpendicular magnetic recording medium. The group A includes an FePt ordered alloy, a CoPt ordered alloy, an FePd ordered alloy and an alloy thereof. This information recording layer has a very small magnetic domain structure and allows high density recording as seen from a signal output spectrum showing a result of a recording and reproducing evaluation of a magnetic recording medium in one example. The information recording layer can be formed at lower film formation temperature than a temperature of a composite thin film of an ordered alloy of L10 crystal structure according to a conventional technique.
    Type: Grant
    Filed: September 13, 2001
    Date of Patent: July 29, 2003
    Assignee: Governor of Akita Prefecture
    Inventors: Toshio Suzuki, Naoki Honda, Kazuhiro Ouchi
  • Publication number: 20020041980
    Abstract: An information recording layer consisting of a composite of an ordered alloy of L10 crystal structure selected from a group A, and MgO is used for a perpendicular magnetic recording medium. The group A includes an FePt ordered alloy, a CoPt ordered alloy, an FePd ordered alloy and an alloy thereof. This information recording layer has a very small magnetic domain structure and allows high density recording as seen from a signal output spectrum showing a result of a recording and reproducing evaluation of a magnetic recording medium in one example. The information recording layer can be formed at lower film formation temperature than a temperature of a composite thin film of an ordered alloy of L10 crystal structure according to a conventional technique.
    Type: Application
    Filed: September 13, 2001
    Publication date: April 11, 2002
    Applicant: Governor of Akita Prefecture
    Inventors: Toshio Suzuki, Naoki Honda, Kazuhiro Ouchi
  • Patent number: 6091556
    Abstract: A data recording device such as a hard disk apparatus has an orthogonal coding circuit and a modulation circuit. The orthogonal coding circuit encodes recording data to be recorded to adjacent two tracks as two orthogonal code streams which are included in an Hadamard matrix. The modulation circuit outputs recording signals, which are obtained by modulating the code streams using the NRZI system, to a magnetic head. Reproduction signals read out from a magnetic disk by the magnetic head are decoded as recording data based upon given decoding rules according to the two code streams.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: July 18, 2000
    Assignee: Governor of Akita Prefecture
    Inventors: Kazuhiro Ouchi, Naoki Honda, Atsushi Kikawada
  • Patent number: 6068739
    Abstract: A method of manufacturing a data recording medium for recording and reproducing data by use of a magnetic field or light and formed of an ordered alloy thin film comprising the steps of forming at least one underlayer principally containing an element or a compound selected from the group consisting of Cr, Pt, Pd, Au, Fe, Ni, MgO, NiO and controlled in such a way that a crystal plane having a crystal lattice face of a Miller index (100) is in parallel to a substrate, and forming an ordered alloy layer with L1.sub.0 crystal structure by sputter deposition within the range satisfying Equation 1: P.times.D>3000, where P is Ar sputter-gas pressure (Pa) and D is a target-substrate distance (mm), is disclosed.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: May 30, 2000
    Assignee: Governor of Akita Prefecture
    Inventors: Toshio Suzuki, Naoki Honda, Kazuhiro Ouchi
  • Patent number: 5759682
    Abstract: A thin film magnetic recording medium comprising, a substrate, a crystal orientation enhancement underlayer of hcp structure formed on the substrate, a perpendicular orientation dispersion angle of c-axis thereof being not more than 10 degrees, and a cobalt-chromium-based magnetic layer formed on the underlayer, the magnetic layer having a thickness of 100 nm or less and containing 1 to 8 at % of niobium.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: June 2, 1998
    Assignee: Governor of Akita Perfecture
    Inventors: Kazuhiro Ouchi, Naoki Honda