Patents Examined by Christopher R Beachman
  • Patent number: 6680899
    Abstract: An optical information medium comprising a supporting substrate, an information recording area on the supporting substrate, and a light-transmitting layer covering at least the information recording area, wherein the information recording area is irradiated with the recording/reading laser beam through the light-transmitting layer, and wherein the light-transmitting layer is highly scratch resistant upon contact with the optical pickup is provided. Also provided is an optical information medium which has a scratch-resistant light transmitting layer, and which experiences reduced vibration in high-speed rotation without suffering from problems in focus servo and tracking servo. In such optical information medium, the surface of the medium on the side of the laser beam incidence at least in the part above the information recording area has a dynamic coefficient of friction of up to 0.4.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: January 20, 2004
    Assignee: TDK Corporation
    Inventors: Tsuyoshi Komaki, Hideki Hirata, Naoki Hayashida, Toshifumi Tanaka