| 摘要 |
PURPOSE:To make it possible to bring a desired data track under follow-up control easily by a track servo mechanism by providing spots on the data track at even intervals. CONSTITUTION:On data tracks 30 and 31 of rotary disk 5 where spots are formed by light beams, extremely-small spots 32-35 are provided previously at even intervals, and lines of those spots are allotted to the binary state of binary data. In recording mode, a spot showing state ''1'' or ''0'' of binary data is formed between even-interval spots. Thus, track positions in recording mode can easily be detected by even-interval spots, so that track follow-up control can easily be carried into effect. |
