Patent · US Expired

Optical disc device

US6434098B1 · kind B1 · utility

1Cited by
7References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 2001
Grant dateAug 13, 2002
Priority date
Expiry dateApr 25, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B20/10527
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical disc drive usable with discs to which data is continuously recorded and discs having a sector format can quickly resume playback signal output after passing imperfection causing potential reading errors, and plays disc with few read errors. A detection signal generator detects DC level fluctuation in the playback signal read from the disc and generates a detection signal tracking the DC level fluctuation. A selector selects a detection signal or a null signal without valid polarity based on the detection signal generated by the detection signal generator and input to the selector. A clamping unit performs a clamping process to suppress DC level fluctuation in the playback signal based on the detection signal when the selection unit selects the detection signal, and does not perform the clamping process when the selection unit selects the null signal. A signal processor performs specific signal processes based on clamping unit output.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.