Timing system for laser disc having digital information
US4651231A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 13, 1984 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Sep 13, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A timing system is disclosed for reading symbol sites, analog or digital from a video signal preferable in a recorded laser format. A video signal having analog data events at precise timed intervals is recorded on a first commercial grade video recorder. The tape is replayed through a second commercial grade recorder to an optical lathe. At the time of playback to the optical lathe, a timing signal is derived from a phase lock loop circuit added to the second commercial grade and recorded on the FM band of the video signal, which signal is then etched by the lathe onto a master optical disc. Simultaneously with the recordation of the substantially continuous FM band, selected horizontal scans on each frame are loaded with both timing and reference level data, the timing portion of these selected scans being later used for phase comparison of the signal. An optical disc master results which has a continuous FM band timing track as well as an interleaved timing information contained in the video signal. Replication from the optical master to stamped copies occurs with the stamped copies being distributed to discrete players for data access. At each player, the continuous FM band tim…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.