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:
Aug. 26, 2008
Filed:
May. 02, 2007
Akihisa Horiuchi, Utsunomiya, JP;
Akihisa Horiuchi, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens comprises, in the following order from the object side to the image side, a positive first lens unit, a negative second lens unit, which moves during zooming, a positive third lens unit, and a positive fourth lens unit, which moves during zooming. The first lens unit includes a negative lens subunit and a positive lens subunit. The negative lens subunit includes at least two negative lenses each having a concave surface facing the image side and at least one positive lens arranged from the object side. The positive lens subunit includes at least one biconvex positive lens, a negative lens and at least two positive lenses arranged from the object side, or at least one biconvex positive lens, a cemented lens composed of a negative lens and a positive lens and at least one positive lens arranged from the object side.