Record carrier having a servo track with non-modulated parts at a first frequency and modulated parts at a second frequency, and apparatus for scanning the record carrier
US7085209B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2002 |
| Grant date | Aug 1, 2006 |
| Priority date | — |
| Expiry date | May 7, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2562
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A record carrier (1) has a servo track (4) indicating an information track (9) intended for recording information blocks represented by marks, the servo track (4) having a periodic variation of a physical parameter at a first frequency and modulated parts for encoding record carrier information. The modulated parts have a bit synchronization element constituted by a phase modulation of the periodic variation and a data part having data bits of the record carrier information encoded by direct digital modulation. Alternatively, the modulated parts include a second frequency, which is substantially different from the first frequency, for encoding data bits of the record carrier information, the second frequency being a integral multiple N of the first frequency. A recording and/or playback device has a device for recording/reading the information blocks and for reading the record carrier information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.