Optical: systems and elements – Lens – With field curvature shaping
Reexamination Certificate
2011-08-02
2011-08-02
Collins, Darryl J (Department: 2873)
Optical: systems and elements
Lens
With field curvature shaping
C359S793000, C359S691000
Reexamination Certificate
active
07990621
ABSTRACT:
Disclosed are a projection lens that has a simple inner focus structure, an appropriate back focal length, telecentricity, a high optical performance, and a small size and can effectively correct, particularly, lateral chromatic aberration, and a projection display device. A projection lens includes a first lens group having a negative refractive power and a second lens group having a positive refractive power arranged in this order from a magnification side. A fifth lens arranged closest to a reduction side in the first lens group is moved along an optical axis to adjust focus, and at least two lenses are made of a material with anomalous dispersion capable of reducing chromatic aberration in a wide visible range.
REFERENCES:
patent: 6317269 (2001-11-01), Yamamoto
patent: 6496310 (2002-12-01), Fujimoto
patent: 7079324 (2006-07-01), Yamasaki
patent: 7212349 (2007-05-01), Mitsuki
patent: 2009/0109543 (2009-04-01), Nagatoshi
patent: 2001-166205 (2001-06-01), None
“Ohara Inc. : S-FPL.” OHARA. Web. 08 Oct. 2010. <http://www.ohara-inc.co.jp/en/product/optical/list/s-fpl.html>.
Birch & Stewart Kolasch & Birch, LLP
Collins Darryl J
Fujinon Corporation
Wilkes Zachary
LandOfFree
Projection lens and projection display device using the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Projection lens and projection display device using the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Projection lens and projection display device using the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2724833