Patent · US Expired

Optical information recording apparatus

US7480216B2 · kind B2 · utility

2Cited by
3References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 2004
Grant dateJan 20, 2009
Priority date
Expiry dateMay 1, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0013
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A rewritable optical disk apparatus, optical information recording and reproducing apparatus or the like is allowed to automatically and properly adjust the optical system to the optimum focal condition regardless of the readout signal detector's positional error and the residual aberration in the optical system. The spherical aberration and defocus are coarsely adjusted using the amplitude (PP amplitude) of the tracking error signal and then finely adjusted using the amplitude (RF amplitude) of the readout signal. Since the spherical aberration can properly be adjusted, it is possible to raise the reliability of the readout signal.

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