The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 03, 2018
Filed:
Aug. 26, 2016
Applicant:
Canon Kabushiki Kaisha, Tokyo, JP;
Inventor:
Junya Ichimura, Utsunomiya, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 13/18 (2006.01); G02B 7/04 (2006.01); G02B 13/16 (2006.01);
U.S. Cl.
CPC ...
G02B 7/04 (2013.01); G02B 13/16 (2013.01); G02B 13/18 (2013.01);
Abstract
A projection optical system includes a first lens unit that moves in a direction of an optical axis in adjusting an amount of field curvature and a second lens unit located closer to a reduction side than the first lens unit. The first lens unit includes an aspherical lens satisfying predetermined conditional equations.