Patent · US Expired

Skew detection method, optical pickup, and optical disc device

US7218580B2 · kind B2 · utility

1Cited by
7References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 12, 2003
Grant dateMay 15, 2007
Priority date
Expiry dateJul 12, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/24082
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

There is employed a configuration to detect, by making use of an optical pick-up (104) when tracking servo is performed along wobble grooves of an optical disc (102), phase errors between main wobble signal outputted as the result of the fact that reflected light beams corresponding to main spot of the optical disc (102) are received at a main light receiving section (321) of light detecting means (32) and side wobble signals outputted every side spot as the result of the fact reflected light beams corresponding to respective side spots of the optical disc (102) are received at a first sub-light receiving section (322) and a second sub-light receiving section (323) to calculate difference between the both phase errors at a difference calculating circuit (59) to generate, from this difference, a skew signal including inclination direction and inclination quantity of the optical disc (102).

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