Optical disk drive
US5109369A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1989 |
| Grant date | Apr 28, 1992 |
| Priority date | — |
| Expiry date | May 26, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2525
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disc drive is disclosed in which an optical disc on which pregrooves are formed for affording wobble signals frequency modulated by predetermined data signals is driven at a constant linear velocity. Until the time that the data signals obtained upon demodulating the wobble signals are taken out correctly, the reproduced wobble signals are compared with a predetermined reference signal so that a spindle motor for rotating the optical disc is controlled so as to be driven at an approximately constant linear velocity. After it is detected that the data signals obtained upon demodulating the wobble signals are taken out correctly, the spindle motor is driven in a controlled manner on the basis of data signals obtained upon demodulating the reproduced wobble signals so that the spindle motor is controlled so as to be driven at a constant linear velocity. In this manner, the optical disc is controlled immediately at the start time of the optical disc or at the time of track jump by the optical head so that the optical disc is driven a constant linear velocity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.