Light integration unit, optical pickup device using the...

Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C369S112120, C369S112150

Reexamination Certificate

active

07315502

ABSTRACT:
An object of the present invention is to attain stable tracking servo performance by suppressing an offset caused by a shift of an object lens or a tilt of a disk, despite the one-beam method which does not cause reduction in light quantity of the main beam. A diffraction grating is provided between a hologram and a light receiving section, and a diffraction efficiency of the diffraction grating is varied in a grating longitudinal direction. For example, if an incident light beam on the diffraction grating is shifted in the grating longitudinal direction, the quantity of received light in each light receiving section varies to cause offset. By performing tracking servo so as to cancel the change, it is possible to correct the offset, thereby attaining stable tracking servo performance.

REFERENCES:
patent: 4731772 (1988-03-01), Lee
patent: 4924079 (1990-05-01), Opheij et al.
patent: 4983017 (1991-01-01), Tsuji et al.
patent: 5315574 (1994-05-01), Saimi et al.
patent: 5353267 (1994-10-01), Katayama
patent: 5475670 (1995-12-01), Hamada et al.
patent: 5500846 (1996-03-01), Ophey
patent: 5633844 (1997-05-01), Maeda et al.
patent: 6868055 (2005-03-01), Ueyama et al.
patent: 2005/0018561 (2005-01-01), Miyake
patent: 62-147401 (1987-07-01), None
patent: 63-222340 (1988-09-01), None
patent: 63-222341 (1988-09-01), None
patent: 04-301228 (1992-10-01), None
patent: 4-301228/1992 (1992-10-01), None
patent: 07-050030 (1995-02-01), None
patent: 7-050030/1995 (1995-02-01), None
patent: 09-044869 (1997-02-01), None
patent: 9-161282 (1997-06-01), None
patent: 9-161282/1997 (1997-06-01), None
patent: 2001-273666/2001 (2001-10-01), None
International Search Report (PCT/JP02/11538) (in Japanese, no translation).
Sakai et al., “Hologram Laser Unit for DVDs (Recording-type)” (Paper presented at Academic Conference of Japan Society for Precision Engineering, Periodical Kansai Session, 2002, Published and Presented on Aug. 1, 2002). (Partial translation).

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

Light integration unit, optical pickup device using the... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Light integration unit, optical pickup device using the..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Light integration unit, optical pickup device using the... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2768208

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