Patents by Inventor Fumiya Omi

Fumiya Omi 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: 4788095
    Abstract: This invention provides a metal oxide magnetic substance represented by the following general formula:MeO.n[Ma.sub.x Mb.sub.y Co.sub.z Fe.sub.2-(x+m/3y+2/3z) O.sub.3 ][wherein, Me, Ma, Mb, x, y, z, m and n are each as mentioned below.Me: at least one divalent metal selected from the group consisting of Ba, Sr and Pb,Ma: at least one trivalent metal selected from the group consisting of Ga, Al, Cr and Rh,Mb: at least one divalent to tetravalent metal selected from the group consisting of Zn (divalent); Ni, In, Sc, Cr, Sb, Bi, Y and Sm (trivalent), and Mo, Ti, Sn, Ta, V, Mn, Ir, Hf, Pd, Nb, Re, Pt, Os, Zr, Tc, Rh, Ge, Ru, W, Te, Pr and Ce (tetravalent) wherein, the metal represented by Mb is not the same as that represented by Me or Ma)x: 0<x.ltoreq.0.5y: 0<y.ltoreq.0.5z: 0<z.ltoreq.0.5 (wherein, 0<x+y+z.ltoreq.1)m: an ionic valency of Mbn: 5.ltoreq.n.ltoreq.
    Type: Grant
    Filed: September 14, 1987
    Date of Patent: November 29, 1988
    Assignee: Ricoh Company, Ltd.
    Inventors: Hazime Machida, Hitoshi Nakamura, Fumiya Omi, Atsuyuki Watada, Yuziro Kaneko
  • Patent number: 4690861
    Abstract: A magneto optical recording medium comprising laminating a reflective layer, a dielectric undercoat layer and a hexagonal magnetoplumbite-type metal oxide magnetic layer on a substrate in order, characterized by that said magnetic layer is made an excellently C axis - orientated perpendicular magnetic film by putting the crystal misfit between said reflective layer and said dielectric undercoat layer formed thereon within .+-.30% and the crystal misfit between said dielectric undercoat layer and said hexagonal magnetoplumbite -type metal oxide magnetic layer formed thereon within .+-.30%, and thus various characteristics are widely improved.
    Type: Grant
    Filed: February 24, 1986
    Date of Patent: September 1, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Hitoshi Nakamura, Yujiro Kaneko, Yasuo Sawada, Hajime Machida, Fumiya Omi, Atsuyuki Watada
  • Patent number: 4670323
    Abstract: The present invention provides a metal oxide magnetic substance represented by the general formula I:MeO.n[Ga.sub.X M.sub.Y.sup.I Fe.sub.2-X-(m/3)Y O.sub.3 ](wherein, Me is at least one member of Ba, Sr and Pb. M.sup.I is at least one member of Zn, Sc, In, Cr, Ir, Ru, Rh, Ti, Ta, Sn and Ge, 5.ltoreq.n.ltoreq.6, O<X.ltoreq.0.8, O<Y.ltoreq.0.8 and m is the ionic valency of M.sup.I) or represented by the general formula II:MeO.n[M.sub.T.sup.II Fe.sub.2-T O.sub.3 ](wherein, Me is at least one member of Ba, Sr and Pb, M.sup.II is at least one member of Ga and Al, 5.ltoreq.n.ltoreq.6 and O<T.ltoreq.1.0), a magnetic film consisting thereof, and a magneto optical recording medium and parpendicular magnetic recording medium having the magnetic film.
    Type: Grant
    Filed: November 23, 1984
    Date of Patent: June 2, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Nakamura, Hazime Machida, Motoharu Tanaka, Atsuyuki Watada, Fumiya Omi, Nobuyuki Koinuma
  • Patent number: 4670322
    Abstract: The present invention provides a metal oxide magnetic substance represented by the general formula I:MeO.multidot.n[Al.sub.X M.sub.Y Fe.sub.2-x-(m/3)Y O.sub.3 ](wherein, Me is at least one member of Ba, Sr and Pb, M is at least one member of Zn, Sc, In, Cr, Ir, Ru, Rh, Ti, Ta, Sn and Ge, 5.ltoreq.n.ltoreq.6, 0<X.ltoreq.0.8, 0<Y.ltoreq.0.6, and m is the ionic valency of M), a magnetic film consisting thereof, and a magneto optical recording medium and a perpendicular magnetic recording medium having the magnetic film.
    Type: Grant
    Filed: November 29, 1984
    Date of Patent: June 2, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Nakamura, Hazime Machida, Motoharu Tanaka, Atsuyuki Watada, Fumiya Omi, Nobuyuki Koinuma