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:
Nov. 18, 2014
Filed:
Sep. 12, 2013
Canon Kabushiki Kaisha, Tokyo, JP;
Yusuke Akiyama, Utsunomiya, JP;
Saburo Sugawara, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens includes, in order from an enlargement side to a reduction side, a first lens unit having positive refractive power and not moving for zooming, a second lens unit having negative refractive power and moving for zooming, a stop, a zooming lens unit having positive refractive power and moving for zooming, and a final lens unit having positive refractive power and not moving for zooming. During zooming from a wide-angle end to a telephoto end, the second lens unit moves to the reduction side and the zooming lens unit moves to the enlargement side. The zooming lens unit includes a cemented lens. The cemented lens includes a negative lens and a positive lens cemented in order from the enlargement side. A cemented surface of the cemented lens has a convex shape on the enlargement side. The zoom lens satisfies predetermined conditions.