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:
Jan. 26, 2016
Filed:
Aug. 02, 2013
Canon Kabushiki Kaisha, Tokyo, JP;
Tomoyuki Nakamura, Utsunomiya, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
A zoom lens includes, in order from an object side: a first positive lens unit not moving for zooming; a second negative lens unit moving during zooming; a third positive lens unit moving during zooming; a fourth positive lens unit moving during zooming; and a fifth positive lens unit not moving for zooming. Each of the lens units includes positive and negative lenses, and satisfies 10<νp−νn<54, −1<β2w<−0.05, −5<β2t<−1, and −1<β34z2<−0.3, where νp is average Abbe constant of the positive lens of the fourth unit, νn an average Abbe constant of the negative lens of the fourth unit, β2w a magnification of the second unit at wide angle end, β2t a magnification of the second unit at telephoto end, and β34z2 a magnification of a combined lens unit including the third and fourth unit at a zoom position where the magnification of the second unit is −1.