Patents by Inventor Chiaki Kiyooka

Chiaki Kiyooka 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).

  • Optical recording medium, optical recording and reproducing device, and recording and reproducing method for the optical recording medium
    Patent number: 6687203
    Abstract: In an optical recording medium, a groove G and/or a land L composing a recording track includes an interrupted portion of a predetermined length in a direction of the recording track, and the interrupted portion is a clock mark to obtain a clock signal. When (clock mark length C1)/(beam spot size D1)=CM, CM≦1.0. This reduces a region to record the control signal, thereby enabling high-density recording and reproduction, reproducing a control signal having a waveform free from distortion, and generating a clock signal in a state of little jitter.
    Type: Grant
    Filed: September 18, 2001
    Date of Patent: February 3, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Chiaki Kiyooka, Nobuo Ogata
  • Optical pickup device
    Patent number: 6614720
    Abstract: Beam shaping means may have a shaping ratio set to allow a light beam emitted from a semiconductor laser and having an elliptic intensity distribution to have an ellipticity of no more than two to obtain a spot achieving high light availability and reduced in size. Furthermore, the shaping ratio can be set to no more than 2.5 to allow a polalized-beam splitter (light separation means) and other components to be arranged in a converged flux passing between the semiconductor laser and a collimator lens.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: September 2, 2003
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuo Ogata, Chiaki Kiyooka, Makoto Horiyama, Kohji Minami, Takahiro Miyake, Yasuo Nakata
  • Optical recording medium, optical recording and reproducing device, and recording and reproducing method for the optical recording medium
    Publication number: 20020058118
    Abstract: In an optical recording medium, a groove G and/or a land L composing a recording track includes an interrupted portion of a predetermined length in a direction of the recording track, and the interrupted portion is a clock mark to obtain a clock signal. When (clock mark length C1)/(beam spot size D1)=CM, CM≦1.0. This reduces a region to record the control signal, thereby enabling high-density recording and reproduction, reproducing a control signal having a waveform free from distortion, and generating a clock signal in a state of little jitter.
    Type: Application
    Filed: September 18, 2001
    Publication date: May 16, 2002
    Inventors: Chiaki Kiyooka, Nobuo Ogata