Birch, Stewart, Kolasch & Birch
Optical information recording disc and apparatus for driving the disc
 An optical information recording disc having at least one substrate for recording/reproducing information through an optical unit wherein a spindle hole, through which a spindle is provided as a disc drive system, is formed in a central portion of the substrate and an engagement member engageable with a disc engagement member integrally formed with the spindle, is formed around the central portion. 
Hitachi Maxell, Ltd. Hitachi, Ltd.
G G G
G11B G11B G11B
inventional inventional inventional
Masahiro Koreaki Takeo Akira
Suzuki Kurane Sonobe Saito