Optical disc discriminating device, optical disc reproducing device and discriminating method
US6278672A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 2, 1999 |
| Grant date | Aug 21, 2001 |
| Priority date | — |
| Expiry date | Jun 2, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0013
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup provided opposed to an optical disc D is moved in the optical axis direction with a drive signal from a focus search circuit to detect, with an amplitude detecting circuit, the character "S" shape waveform of large amplitude corresponding to the recording surface of optical disc of the focus error signal FE obtained from the optical pickup and such detected output is counted by a counter. When the character "S" shape waveform of large amplitude appears twice, an interval thereof is measured with a time measuring circuit and width of interval is detected with an interval detecting circuit. The counted value of counter and detected output of the interval detecting circuit are supplied to a microcomputer to automatically detect a type of optical disc. Thereby, a reproducing device which can be used for a plurality of reflection type optical discs may be structured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.