Optical disc apparatus

Dynamic information storage or retrieval – With servo positioning of transducer assembly over track... – Optical servo system

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C369S112160

Reexamination Certificate

active

10390776

ABSTRACT:
Provided is a focus and tracking control method for an optical pick-up apparatus which is used for recording and reproduction of a small-sized optical disc and which can carry out stable focus control and stable tracking control. A focus control method for an optical pick-up apparatus comprising a light source, an objective lens, a light receiving means having divided four light receiving zones and a polarizing means having divided for lattice zones, characterized in that when the reflected light beam is incident upon the four light receiving zones by way of the four lattice zones, focus control is carried out in accordance with a difference signal between the groups, in the radial direction, of the four light receiving zones which are divided into two groups in the radial direction by the division line in parallel with the tangential direction, respectively through the four lattice zones which are divided into two groups in the tangential direction by a division line in parallel with the radial direction. Further, the tracking control for the pick-up apparatus is characterized in that tracking control is carried out in accordance with a difference signal between two groups in the tangential direction.

REFERENCES:
patent: 4533826 (1985-08-01), van Alem
patent: 4945529 (1990-07-01), Ono et al.
patent: 5648951 (1997-07-01), Kato et al.
patent: 6512732 (2003-01-01), Bierhoff et al.
patent: 6928035 (2005-08-01), Komma et al.
patent: 2001/0046195 (2001-11-01), Togashi
patent: 0374841 (1990-06-01), None
patent: 0452793 (1991-10-01), None
patent: 07311989 (1995-11-01), None
patent: 08161768 (1996-06-01), None
patent: 11219529 (1999-08-01), None
patent: 2000251305 (2000-09-01), None
patent: 2001250343 (2001-09-01), None

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Optical disc apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Optical disc apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical disc apparatus will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3804026

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.