Patent · US Expired

Method of and apparatus for adjusting the focus position of an optical pickup

US7064308B2 · kind B2 · utility

0Cited by
2References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 12, 2004
Grant dateJun 20, 2006
Priority date
Expiry dateDec 9, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

It is an object of the present invention to adjust the focus position of an optical pickup. A brightness measuring apparatus having a half mirror and an objective lens focusing on the half mirror is disposed at a position facing an optical pickup PUi, in a manner such that the objective lens OB of the optical pickup PUi faces the half mirror. Then, the optical pickup PUi is operated to start a focus servo, while the position of multi-lens provided in the optical pickup PUi is changed continuously, thereby measuring a highest brightness of a spot light image incident on the half mirror through the objective lens, by virtue of the brightness measuring apparatus. Subsequently, a highest brightness change caused by changing the position of the multi-lens ML is inspected so as to fix the multi-lens ML at a position when the maximum highest brightness has been obtained, thereby effecting an optimum focus position adjustment for an optical pickup.

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