Optical head apparatus, optical information recording and...

Dynamic information storage or retrieval – Condition indicating – monitoring – or testing – Including radiation storage or retrieval

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C369S112030, C369S120000

Reexamination Certificate

active

06967916

ABSTRACT:
An optical head apparatus capable of stably obtaining a detection signal of spherical aberration even with a high density optical disk. A spherical aberration error signal is obtained by: dividing the returning light from the optical disk into a transmitted light and a diffracted light; reproducing information with the transmitted light having a larger amount of light while dividing the diffracted light having a small amount of light into two regions, i.e., region near the optical axis and a region distant from the optical axis; determining amounts of focus deviation in respective regions as focus error signals; and taking the difference signal therebetween. Thus, it is possible to detect the amount of spherical aberration with the SN ratio of the information reproducing signal kept at high level.

REFERENCES:
patent: 6229600 (2001-05-01), Martynov
patent: 6399932 (2002-06-01), Wals
patent: 6498330 (2002-12-01), Yoshida
patent: 6661750 (2003-12-01), Saimi et al.
patent: 2000-171346 (2000-06-01), None
patent: 2000-182254 (2000-06-01), None
patent: 2001-507463 (2001-06-01), None
patent: WO 99/18466 (1999-04-01), 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 head apparatus, optical information recording and... 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 head apparatus, optical information recording and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical head apparatus, optical information recording and... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3500907

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