| 摘要 |
<p>A disc-shaped information carrier (1) and a device for reading and/or writing information blocks in a track (9) are disclosed. For indicating the track (9), the information carrier (1) has a servo pattern (4) which includes position-information and synchronization elements (35, 36). The synchronization elements such as, for example, a brief pulse in a wobble, are distinguishable in adjacent windings (30, 31) of the track (9) in a predeterminable manner, for example as a result of alternating polarity or shifted positions. The device comprises a read/write head and a system control which during writing detects the synchronization elements and monitors whether a deviation occurs that indicates that the read/write head has wandered off to an adjacent winding. Writing is then interrupted. This is advantageous in that the least possible information in adjacent windings is overwritten in the case of disturbances resulting from shocks or defects of the information carrier. Furthermore, a reading device is described which interrupts the reading in dependence on the synchronization elements.</p> |
