Optical: systems and elements – Lens – With field curvature shaping
Reexamination Certificate
2008-09-18
2010-11-30
Harrington, Alicia M (Department: 2873)
Optical: systems and elements
Lens
With field curvature shaping
C355S067000
Reexamination Certificate
active
07843645
ABSTRACT:
This invention is a projection optical system which includes a plurality of lens groups and projects an image of a first object onto a second object. A bottom lens group of the plurality of lens groups which is positioned nearest to the second object is made of an isotropic crystal material having a refractive index of 1.6 or more and has a positive focal length. A curvature radius R (mm) of a surface of the bottom lens group which is located on the first object side and a center thickness d (mm) of the bottom lens group satisfy 3.0>R/d>1.6 and d<60.
REFERENCES:
patent: 6813070 (2004-11-01), Oyama
patent: 7057708 (2006-06-01), Yamada
patent: 2006/0055834 (2006-03-01), Tanitsu et al.
patent: 2006/0198029 (2006-09-01), Schuster
patent: 2008/0043331 (2008-02-01), Kraehmer et al.
patent: 2008/0084546 (2008-04-01), Owa et al.
patent: 2008/0212058 (2008-09-01), Yamada
patent: 05-109601 (1993-04-01), None
patent: 07-142338 (1995-06-01), None
patent: 2004-045692 (2004-02-01), None
patent: 2006-113533 (2006-04-01), None
patent: 2004/051717 (2004-06-01), None
Canon Kabushiki Kaisha
Canon U.S.A. Inc., I.P Division
Harrington Alicia M
LandOfFree
Projection optical system, exposure apparatus, and method of... 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 optical system, exposure apparatus, and method of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Projection optical system, exposure apparatus, and method of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4169271