Video disc playback apparatus with non-linear aperture correction
US4272786A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 19, 1979 |
| Grant date | Jun 9, 1981 |
| Priority date | — |
| Expiry date | Sep 19, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B9/06
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a video disc playback apparatus, a playback stylus is utilized for the recovery of information from prerecorded disc records. In one system, geometric variations are recorded on the surface of the record and are representative of recorded picture and sound information. As these geometric variations pass beneath the stylus, the capacitance between the stylus electrode and the surface of the disc varies in accordance with the recorded representations. The capacitive variations are converted to electrical signal variations in the playback apparatus. In such a video disc playback apparatus, sound interference in the video and video interference in the sound can be produced by the non-linearity of the aforementioned pickup stylus. Use of a non-linear aperture corrector between the pickup circuitry and the demodulator circuitry of the playback apparatus reduces these interferences.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.