Patents by Inventor Katsusuke Shimazaki

Katsusuke Shimazaki 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: 6044041
    Abstract: A compact recording and reproducing apparatus includes a floating-type head movable in a fan shape in parallel with the surface of a disk recording medium in order to make faster access to the tracks and to record information at a higher density. A slider and a head are secured to the tip of a swing arm capable of fan-shaped swing movement, and a solid immersion lens is used for the head, so that the light beam can be passed along the arm from the fulcrum at the rotating pivot of the swing arm member.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: March 28, 2000
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Osamu Ishizaki, Katsusuke Shimazaki, Toshinori Sugiyama, Masafumi Yoshihiro, Susumu Imai
  • Patent number: 5965286
    Abstract: A magneto-optical recording medium having a thin film, with suitable thermal conductivity, laminated on a magneto-optical film having excellent durability to repeated recording, reproducing and erasing comprising one layer or a multi-layer of thin film containing at least a magneto-optical recording film and carried on a transparent substrate, a ferromagnetic reflection film having a reflectance to a reproduction beam of 70% or higher and a thermal conductivity at a normal temperature from 0.05 to 2.0 W/cm.deg laminated on the backside of the magneto-optical recording film viewed from the transparent substrate side and, optionally, a heat control layer having a thermal conductivity at a normal temperature of 0.1 to 2.0 W/cm.deg laminated on the backside of the magneto-optical film.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: October 12, 1999
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Satoru Ohnuki, Katsusuke Shimazaki, Norio Ohta, Hideo Fujiwara, Masafumi Yoshihiro, Noriyuki Ogihara, Yukinori Yamada
  • Patent number: 5923625
    Abstract: A magneto-optical recording medium and a method for recording and reproduction thereon are provided in order to reproduce information recorded by multi-valued recording at a high S/N ratio. Disclosed is a magneto-optical recording medium including two magnetic layers capable of four-valued recording based on four combined magnetization states. Magnitudes of reproduction signals concerning the four magnetization states, obtained upon reproduction at a wavelength .lambda..sub.1, are different from those obtained upon reproduction at a wavelength .lambda..sub.2. The two magnetic layers, on which a signal (a) is recorded, are irradiated with light beams having the wavelengths .lambda..sub.1 and .lambda..sub.2 respectively. Signals (d), (e) reproduced from respective reflected light beams are sliced by using at least one slice level to obtain two-valued or higher multi-valued reproduction signals respectively.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: July 13, 1999
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Katsusuke Shimazaki, Norio Ohta, Akiyoshi Ito, Katsuji Nakagawa, Kazuko Inoue
  • Patent number: 5783320
    Abstract: Disclosed is a magneto-optical recording medium which comprises a transparent substrate and, provided on the substrate, a magneto-optical recording film comprising a perpendicular magnetic film based on rare earth metal-transition metal and an auxiliary magnetic film having spontaneous magnetization which exerts, between itself and the magneto-optical recording film, an exchange coupling force on each other and in which the auxiliary magnetic film used is a magnetic film which readily rotates its magnetization direction toward the external magnetic field in the neighborhood of the Curie temperature of the magneto-optical recording film and has a squareness ratio of not more than 1 in the neighborhood of the Curie temperature, and a process for producing the magneto-optical recording medium.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: July 21, 1998
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Katsusuke Shimazaki, Satoru Ohnuki, Masatoshi Hashimoto, Yoshinori Shirai, Norio Ohta, Hideo Fujiwara, Masafumi Yoshihiro, Yukinori Yamada, Eiji Koyama, Hitoshi Furusho
  • Patent number: 5639563
    Abstract: A magneto-optical recording medium having a thin film with a suitable thermal conductivity, laminated on magneto-optical film, having excellent durability to repeated recording, reproducing and erasing comprising one layer or a multi-layer of thin film containing at least a magneto-optical recording film carried on a transparent substrate, a ferromagnetic reflection film having a reflectance to a reproduction beam of 70% or higher and a thermal conductivity at a normal temperature from 0.05 to 2.0 W/cm.deg laminated on the backside of the magneto-optical recording film viewed from the transparent substrate side and, optionally, a heat control layer having a thermal conductivity at a normal temperature of 0.1 to 2.0 W/cm.deg may be laminated on the backside of the magneto-optical film.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: June 17, 1997
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Satoru Ohnuki, Katsusuke Shimazaki, Norio Ohta, Hideo Fujiwara, Masafumi Yoshihiro, Noriyuki Ogihara, Yukinori Yamada
  • Patent number: 5637411
    Abstract: Disclosed is a magneto-optical recording medium which comprises a transparent substrate and, provided on the substrate, a magneto-optical recording film comprising a perpendicular magnetic film based on rare earth metal-transition metal and an auxiliary magnetic film having spontaneous magnetization which exerts, between itself and the magneto-optical recording film, an exchange coupling force and wherein the auxiliary magnetic film is a magnetic film which readily rotates its magnetization direction toward the external magnetic field in the neighborhood of the Curie temperature of the magneto-optical recording film and has a squareness ratio of not more than 1 in the neighborhood of the Curie temperature. Also disclosed is a process for producing the magneto-optical recording medium.
    Type: Grant
    Filed: April 14, 1994
    Date of Patent: June 10, 1997
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Katsusuke Shimazaki, Satoru Ohnuki, Masatoshi Hashimoto, Yoshinori Shirai, Norio Ohta, Hideo Fujiwara, Masafumi Yoshihiro, Yukinori Yamada, Eiji Koyama, Hitoshi Furusho
  • Patent number: 5590097
    Abstract: A magnetooptic recording medium which includes a substrate and a magnetooptic recording film thereon, the substrate having a surface comparted into a plurality of tracks on which magnetooptic recording signals are recorded, and a part of the tracks, selected from the plurality of tracks, including clusters of pre-pits wherein a variation of a change in light amount due to local birefringence in the vicinity of the pre-pits is not more than 20% with respect to a change in light amount in the absence of the local birefringence, when signals from the tracks with recorded magnetooptic recording signals are measured by changes in light amount on the basis of Kerr rotational angles of reflected light from the medium, which magnetooptic recording medium can be effectively used for a ZCAV system.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: December 31, 1996
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Akira Kashiwakura, Katsusuke Shimazaki, Masafumi Yoshihiro, Shin-Itsu Kinoshita, Norio Oota, Hisanori Sugiyama