Patents by Inventor Motonobu Mihara

Motonobu Mihara 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: 7164623
    Abstract: The present invention provides a magneto-optical recording medium including a recording layer, an intermediate layer and a reproducing layer stacked in this order. Information recorded in the recording layer is transferred to the reproducing layer through the intermediate layer so that the information is reproduced. The reproducing layer includes an upper reproducing layer, a coupling layer, and a lower reproducing layer formed in this order on the intermediate layer. Magnetic information in the upper reproducing layer in an area whose temperature is increased to a predetermined temperature is transferred to the lower reproducing layer through the coupling layer.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: January 16, 2007
    Assignee: Fujitsu Limited
    Inventors: Ryo Kurita, Ken Tamanoi, Shoyu Ito, Motonobu Mihara
  • Publication number: 20050024993
    Abstract: The present invention provides a magneto-optical recording medium including a recording layer, an intermediate layer and a reproducing layer stacked in this order. Information recorded in the recording layer is transferred to the reproducing layer through the intermediate layer so that the information is reproduced. The reproducing layer includes an upper reproducing layer, a coupling layer, and a lower reproducing layer formed in this order on the intermediate layer. Magnetic information in the upper reproducing layer in an area whose temperature is increased to a predetermined temperature is transferred to the lower reproducing layer through the coupling layer.
    Type: Application
    Filed: August 25, 2004
    Publication date: February 3, 2005
    Inventors: Ryo Kurita, Ken Tamanoi, Shoyu Ito, Motonobu Mihara
  • Patent number: 6770387
    Abstract: A magneto-optical recording medium comprising four magnetic layers including a mask layer, a reproduction layer, an intermediate layer and a recording layer, wherein the reproduction layer and the recording layer each have a direction of easy magnetization extending in a layer stacking direction at room temperature, the mask layer and the intermediate layer each have a direction of easy magnetization extending in an in-plane direction at room temperature, the mask layer, the reproduction layer, the intermediate layer and the recording layer have Curie temperatures Tc1, Tc2, Tc3 and Tc4, respectively, which satisfy relationships of Tc3<Tc2, Tc3<Tc4 and Tc3<Tc1, and the intermediate layer is a rare-earth-rich magnetic layer.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: August 3, 2004
    Assignee: Fujitsu Limited
    Inventors: Tsutomu Tanaka, Motonobu Mihara, Ken Tamanoi
  • Publication number: 20020118832
    Abstract: The present invention is a system capable of protecting copyright and personal information appropriately and allowing users to readily obtain desired contents in a short time at low prices. A recording device stores contents in advance. The recording device encrypts the contents, based on an identifier given uniquely to a medium. The recording device records the encrypted contents on the medium. Moreover, the recording device records limiting conditions for reproducing, displaying or executing the contents on the medium. An execution device decrypts the contents recorded on the medium, based on the identifier. The execution device reproduces, displays or executes the contents under the limiting conditions recorded on the medium.
    Type: Application
    Filed: July 3, 2001
    Publication date: August 29, 2002
    Inventors: Michio Matsuura, Keiji Shono, Kazuyuki Ozaki, Mineo Moribe, Motonobu Mihara, Koji Matsumoto, Seigo Kotani
  • Publication number: 20020119347
    Abstract: A magneto-optical recording medium comprising four magnetic layers including a mask layer, a reproduction layer, an intermediate layer and a recording layer, wherein the reproduction layer and the recording layer each have a direction of easy magnetization extending in a layer stacking direction at room temperature, the mask layer and the intermediate layer each have a direction of easy magnetization extending in an in-plane direction at room temperature, the mask layer, the reproduction layer, the intermediate layer and the recording layer have Curie temperatures Tc1, Tc2, Tc3 and Tc4, respectively, which satisfy relationships of Tc3<Tc2, Tc3<Tc4 and Tc3<Tc1, and the intermediate layer is a rare-earth-rich magnetic layer.
    Type: Application
    Filed: December 5, 2001
    Publication date: August 29, 2002
    Applicant: Fujitsu Limited
    Inventors: Tsutomu Tanaka, Motonobu Mihara, Ken Tamanoi
  • Patent number: 6356516
    Abstract: A magneto-optical recording medium capable of perfectly masking a mark adjacent to a mark to be reproduced thereby improvng reproduction output. The magneto-optical recording medium includes a transparent substrate, a magnetic reproducing layer laminated on the transparent substrate, a nonmagnetic intermediate layer laminated on the magnetic reproducing layer, and a magnetic recording layer laminated on the nonmagnetic intermediate layer. The reproducing layer has an easy direction of magnetization in a plane at room temperature, and has an easy direction of magnetization perpendicular to a film surface at a given temperature or higher. The nonmagnetic intermediate layer is thin enough to allow magnetostatic bond between the recording layer and the reproducing layer at the given temperature or higher.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: March 12, 2002
    Assignee: Fujitsu Limited
    Inventors: Ken Tamanoi, Keiji Shono, Sumio Kuroda, Motonobu Mihara, Koji Matsumoto
  • Patent number: 6248439
    Abstract: A magneto-optical recording medium capable of perfectly masking a mark adjacent to a mark to be reproduced thereby improving a reproduction output. The magneto-optical recording medium includes a transparent substrate, a magnetic reproducing layer laminated on the transparent substrate, a nonmagnetic intermediate layer laminated on the magnetic reproducing layer, and a magnetic recording layer laminated on the nonmagnetic intermediate layer. The reproducing layer has an easy direction of magnetization in a plane at room temperature, and has an easy direction of magnetization perpendicular to a film surface at a given temperature or higher. The nonmagnetic intermediate layer is thin enough to allow magnetostatic bond between the recording layer and the reproducing layer at the given temperature or higher.
    Type: Grant
    Filed: January 4, 1995
    Date of Patent: June 19, 2001
    Assignee: Fujitsu Ltd.
    Inventors: Ken Tamanoi, Keiji Shono, Sumio Kuroda, Motonobu Mihara, Koji Matsumoto
  • Publication number: 20010000483
    Abstract: A magneto-optical recording medium capable of perfectly masking a mark adjacent to a mark to be reproduced to thereby improve a reproduction output. The magneto-optical recording medium includes a transparent substrate, a magnetic reproducing layer laminated on the transparent substrate, a nonmagnetic intermediate layer laminated on the magnetic reproducing layer, and a magnetic recording layer laminated on the nonmagnetic intermediate layer. The reproducing layer has an easy direction of magnetization in a plane at room temperature, and has an easy direction of magnetization perpendicular to a film surface at a given temperature or higher. The nonmagnetic intermediate layer is thin enough to allow magnetostatic bond between the recording layer and the reproducing layer at the given temperature or higher.
    Type: Application
    Filed: December 7, 2000
    Publication date: April 26, 2001
    Applicant: Fujitsu Limited
    Inventors: Ken Tamanoi, Keiji Shono, Sumio Kuroda, Motonobu Mihara, Koji Matsumoto
  • Patent number: 6030716
    Abstract: A magneto-optical recording medium adapted for reproduction of a high resolution signal without the necessity of a reproducing magnetic field. The magneto-optical recording medium comprises a transparent substrate and deposits of a reproducing layer, a switch layer and a recording layer formed on the transparent substrate successively. The reproducing layer is a perpendicular magnetization film at a room temperature but is turned to an in-plane magnetization film when heated beyond a predetermined temperature. Each of the switch layer and the recording layer is a perpendicular magnetization film. The respective Curie temperatures Tc1, Tc2 and Tc3 of the reproducing layer, the switch layer and the recording layer satisfy the relationship of Tc1>Tc3>Tc2.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: February 29, 2000
    Assignee: Fujitsu Limited
    Inventors: Haruhiko Izumi, Ken Tamanoi, Masaharu Moritsugu, Miyozo Maeda, Toshio Sugimoto, Koji Matsumoto, Motonobu Mihara
  • Patent number: 6031794
    Abstract: A magneto-optical recording medium, and a method of its production, a method of reading and an apparatus of reading the same capable of decreasing the magnetic field to be applied during MSR readout, or reading without applying magnetic field, by including first, second and third magnetic layers having specified magnetic characteristics.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: February 29, 2000
    Assignee: Fujitsu Limited
    Inventors: Ken Tamanoi, Toshio Sugimoto, Tsutomu Tanaka, Motonobu Mihara, Keiji Shono
  • Patent number: 5965285
    Abstract: A magneto-optical recording medium having first magnetic layer and second magnetic layers respectively serving as recording and reproduction layers. When an exchange-coupled force is induced between the layers, the reproducing layer takes on an identical magnetization direction as the recording layers permitting the data stored in the recording layer to be reproduced via the reproducing layer. An intermediate layer formed between the first and second magnetic layers is formed of an antiferromagnetic and has a N.epsilon.el temperature higher than the temperature at which the reproducing layer mirrors the magnetization direction of the recording layer. A medium in accordance with the present invention may also include a third magnetic layer for controlling the recording and erasing of data from the first layer, and a fourth magnetic layer for holding a magnetization direction during a data erasing operation.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: October 12, 1999
    Assignee: Fujitsu Limited
    Inventors: Motonobu Mihara, Ken Tamanoi
  • Patent number: 5896350
    Abstract: A magneto-optical recording medium, and a method of its production, a method of reading and an apparatus of reading the same capable of decreasing the magnetic field to be applied during MSR readout, or reading without applying magnetic field, by including first, second and third magnetic layers having specified magnetic characteristics.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: April 20, 1999
    Assignee: Fujitsu Limited
    Inventors: Ken Tamanoi, Toshio Sugimoto, Tsutomu Tanaka, Motonobu Mihara, Keiji Shono
  • Patent number: 5691072
    Abstract: Disclosed is a magneto-optical recording medium adapted for reproduction of a high resolution signal without the necessity of a reproducing magnetic field, whereby the magneto-optical recording medium comprises a transparent substrate, a reproducing layer, a switch layer and a recording layer formed on the transparent substrate successively. The reproducing layer is a perpendicular magnetization film at a room temperature but is turned to an in-plane magnetization film when heated beyond a predetermined temperature. Each of the switch layer and the recording layer is a perpendicular magnetization film. The respective Curie temperatures Tc1, Tc2 and Tc3 of the reproducing layer, the switch layer and the recording layer satisfy the relationship of Tc1>Tc3>Tc2.
    Type: Grant
    Filed: January 31, 1995
    Date of Patent: November 25, 1997
    Assignee: Fujitsu Limited
    Inventors: Haruhiko Izumi, Ken Tamanoi, Masaharu Moritsugu, Miyozo Maeda, Toshio Sugimoto, Koji Matsumoto, Motonobu Mihara