Tracking device for optical memory card
US5128917A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 13, 1989 |
| Grant date | Jul 7, 1992 |
| Priority date | — |
| Expiry date | Oct 13, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0901
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Tracking device for an optical memory card includes an inclination information sampling unit for calculating changes per unit time of the low-frequency component of a tracking error signal, a detection unit for outputting a detection signal for duration of a deviation occurring during tracking that exceeds a predetermined standard range, a cumulative addition unit for cumulatively adding the output of the inclination information sampling unit of the low-frequency component of the tracking error signal that is generated when the detection signal is generated at each unit time during the generation of the detection signal, and a switch-over unit for outputting as an optical system tracking control signal the tracking error signal during the normal operation and the output of the cumulative addition unit during the outputting of the detection signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.