Patents by Inventor Yoshikatsu Takeoka

Yoshikatsu Takeoka 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: 4845000
    Abstract: A radiation-sensitive carrier body directly utilized as a stamper has a glass substrate, a first highly adhesive layer securely adhered to the substrate, a radiation-sensitive layer which discharges a gas component upon being irradiated with a laser beam and which locally forms a protuberance due to the absorbed energy, a second highly adhesive layer securely adhered to the specific material of the radiation-sensitive layer and which deforms in accordance with deformation of the layer, and a metal layer which has a high releasability to allow easy separation from a optical disk substrate material such as an acrylic material when the carrier body is used as a stamper substrate for manufacturing optical disks. A protuberance formed on the carrier body such as a continuous spiral protuberance allows formation of a corresponding spiral groove in the acrylic material, serving as a pre-track into which desired information will be digitally written by a user.
    Type: Grant
    Filed: December 4, 1986
    Date of Patent: July 4, 1989
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Yoshikatsu Takeoka, Nobuaki Yasuda, Akio Hori, Norio Ozawa
  • Patent number: 4756811
    Abstract: There is disclosed a method for manufacturing a bubble-mode optical disk having a recording layer made of a mixture of an indium oxide matrix containing indium clusters and organic clusters. The indium clusters absorb an energy of incident laser beam to heat the organic clusters which then release a gas component such that the matrix is locally deformed to form a protuberance. A plasma sputtering is used to deposit the recording layer on a disk substrate placed in a sputtering chamber. A target body used is made of indium. A low-pressure gaseous atmosphere in the chamber includes a methane series hydrocarbon gas and an oxygen gas. The gaseous atmosphere may include a hydrogen gas or a nitrogen gas.
    Type: Grant
    Filed: September 30, 1986
    Date of Patent: July 12, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshikatsu Takeoka, Nobuaki Yasuda, Norio Ozawa
  • Patent number: 4735888
    Abstract: A disk-shaped recording medium of the invention has a photosensitive recording layer formed on a substrate. Tellurium oxide clusters are dispersed in a hydrocarbon matrix of the recording layer so as to thermally stabilize the matrix. Tellurium clusters are dispersed in the matrix which is thermally stabilized by dispersion of the tellurium oxide clusters. The recording layer has excellent oxidation and heat resistance. The recording medium is manufactured by a plasma sputtering technique.
    Type: Grant
    Filed: January 30, 1986
    Date of Patent: April 5, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshikatsu Takeoka, Norio Ozawa, Nobuaki Yasuda
  • Patent number: 4702991
    Abstract: In an optical disk, a single recording layer is formed on a transparent substrate. The recording layer has an insulative base layer in which metal clusters and organic clusters are uniformly contained. When radiation is incident on the recording layer such that the intensity of the radiation is changed in accordance with the type of recording information, the metal clusters absorb radiation energy. The organic clusters produce a gas component in accordance with a level of the radiation energy absorbed by the metal clusters, thereby causing the base layer to incur a local projection by a pressure of the gas component such that a protuberance is formed on the base layer.
    Type: Grant
    Filed: June 20, 1986
    Date of Patent: October 27, 1987
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshikatsu Takeoka, Norio Ozawa, Nobuaki Yasuda
  • Patent number: 4663008
    Abstract: An optical information recording medium is produced by introducing a plasma-generation gas comprising hydrocarbon into a plasma-generating region provided with a metal target and a substrate. The pressure of the plasma-generating gas is maintained within a predetermined range within the plasma-generating region. Electrical power is applied to the plasma-generating gas to dissociate the gas thereby forming a plasma. The generated plasma sputters the metal target, thereby allowing the sputtered metal to be deposited on the substrate in the form of a film containing the metal and the carbon liberated from the hydrocarbon. During sputtering, the product between the density of the power applied to the electrode and the average residence time of the plasma-generating gas within the plasma-generating region is controlled within such that the product falls within the range of more than 0.5 W-sec/cm.sup.2 and less than 50 W-sec/cm.sup.
    Type: Grant
    Filed: July 21, 1986
    Date of Patent: May 5, 1987
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshikatsu Takeoka, Norio Ozawa, Nobuaki Yasuda
  • Patent number: 4647947
    Abstract: A disk-shaped optical type recording medium is disclosed which includes a transparent substrate and recording layer formed on the substrate. The recording layer in a single layer, which is made of a material capable of absorbing energy reaching it through the substrate and being locally raised on one surface according to the absorbed heat energy of the laser beam.
    Type: Grant
    Filed: September 13, 1985
    Date of Patent: March 3, 1987
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Yoshikatsu Takeoka, Nobuaki Yasuda
  • Patent number: 4565772
    Abstract: A radiation-sensitive carrier body directly utilized as a stamper has a glass substrate, a first highly adhesive layer securely adhered to the substrate, a radiation-sensitive layer which discharges a gas component upon being irradiated with a laser beam and which locally forms a protuberance due to the absorbed energy, a second highly adhesive layer securely adhered to the specific material of the radiation-sensitive layer and which deforms in accordance with deformation of the layer, and a metal layer which has a high releasability to allow easy separation from a optical disk substrate material such as an acrylic material when the carrier body is used as a stamper substrate for manufacturing optical disks. A protuberance formed on the carrier body such as a continuous spiral protuberance allows formation of a corresponding spiral groove in the acrylic material, serving as a pre-track into which desired information will be digitally written by a user.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: January 21, 1986
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Yoshikatsu Takeoka, Nobuaki Yasuda, Akio Hori, Norio Ozawa
  • Patent number: 4478768
    Abstract: A specific laser-sensitive layer is formed on a substrate so as to manufacture an original disk. The laser-sensitive layer absorbs energy from a laser beam and locally expands and deforms. The laser beam which has a predetermined beam energy to indicate pretrack information for, for example, a self-write/read type optical disk, is used to irradiate the laser-sensitive layer. A spiral projected pattern is locally formed on the laser-sensitive layer, such that a gas is discharged from laser-incident portion which then expands and deforms. A structure so obtained is used as an original disk.
    Type: Grant
    Filed: March 8, 1983
    Date of Patent: October 23, 1984
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Yoshikatsu Takeoka, Nobuaki Yasuda