Autofocus device detecting focus point with liquid crystal lens

Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C250S208100

Reexamination Certificate

active

07910868

ABSTRACT:
Predetermined voltage is applied to a liquid crystal lens by a liquid crystal lens driver. Image signals are generated based on an optical image passed through the liquid crystal lens during transient response operation caused by application of the predetermined voltage, and plural focus signals are extracted by sampling the image signals at predetermined cycles. Levels of the extracted autofocus signals are compared to determine the maximum value of the autofocus signal. Thus, with the liquid crystal lens, by making use of the transient response operation of the liquid crystal lens, a focus point can be detected in sufficient speed.

REFERENCES:
patent: 7532303 (2009-05-01), Kato et al.
patent: 7683975 (2010-03-01), Kageyama
patent: 2002/0041445 (2002-04-01), Nishioka et al.
patent: 2002/0145701 (2002-10-01), Sun et al.
patent: 61-140908 (1986-06-01), None
patent: 61-156228 (1986-07-01), None
patent: 62-36632 (1987-02-01), None
patent: 1-15188 (1989-03-01), None
patent: 2-11068 (1990-03-01), None
patent: 2-44248 (1990-11-01), None
patent: 5-53089 (1993-03-01), None
patent: 2742741 (1998-02-01), None
patent: 3047082 (2000-03-01), None
patent: 2001-154085 (2001-06-01), None
patent: 2002-122784 (2002-04-01), None
patent: 2002-228816 (2002-08-01), None
patent: 2004-191893 (2004-07-01), None
Hain M et al., Fast switching liquid crystal lenses for a dual focus digital versatile disc pickup, Optics Communication, North-Holland Publishing Co. Amsterdam, NL, vol. 188, No. 5-6, Feb. 15, 2001 pp. 291-299.
Kentaro Hanma et al., “Auto Focus System by Detecting Edge Component of Video Signal”, Institute of Television Engineers (ITE) Technical Report, Nov. 1982, p. 7-12, vol. 6, No. 29, and a partial English translation of p. 7.

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

Autofocus device detecting focus point with liquid crystal lens does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Autofocus device detecting focus point with liquid crystal lens, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Autofocus device detecting focus point with liquid crystal lens will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2721212

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