| 摘要 |
<p>A disc device which reproduces at least a disc (1) in which a servo signal region (3) in which a pit for servo and the like are formed and a data and address signal region (4) on which data and address are written are alternatingly provided along the circumferential direction of the disc (1), and in which signals are recorded depending upon two or more kinds of physical changes on the data and address signal regions (4) among the servo signal regions (3). A signal recorded depending upon one physical change is switched into a signal recorded depending upon another physical change, in the servo signal region (3) or in a no-signal recording region (5c). Therefore, margin is provided for the operation of switching the signals of various recording types, and stable operation can be maintained even when the data are transferred at higher speeds.</p> |
