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:
May. 27, 2014
Filed:
May. 14, 2012
Applicant:
Yosuke Okubo, Chofu, JP;
Inventor:
Yosuke Okubo, Chofu, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 15/177 (2006.01); G02B 13/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A zoom lens includes, in order from an object side to an image side, a first lens unit of a negative refractive power, a second lens unit of a positive refractive power, and a third lens unit of a positive refractive power, each lens unit being moved during zooming, wherein the second lens unit includes two positive lenses, a negative lens, a positive lens in order from the object side to the image side, and an average refractive index Ndfor d-line of materials of the positive lenses in the second lens unit and a refractive index Ndfor d-line of a material of the negative lens in the second lens unit are appropriately set.