Method and arrangement for preventing unauthorized duplication of optical discs using barriers
US5787068A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1996 |
| Grant date | Jul 28, 1998 |
| Priority date | — |
| Expiry date | Nov 7, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0079
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optically-readable data disc includes piracy-protection featuring noncontiguously sequenced data files in zones separated by head-derailing barriers. The disc includes a plurality of data-placement zones and read-blocking barriers constructed along the spiral track over gaps which separate the zones. Data files are recorded in each of the zones, and an address-information data file includes data which identifies addresses of data files to be sequentially read in noncontiguous zones. By arranging the data files noncontiguously with barriers in gaps between the data files, efforts to duplicate the master disc by attempting to read the data files contiguously are deterred and/or prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.