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:
Dec. 27, 2011
Filed:
Mar. 29, 2010
Norihiro Nanba, Utsunomiya, JP;
Norihiro Nanba, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
Provided is a compact and high optical performance zoom lens system, including, in order of from an object side toward an image side: a first lens unit with a negative refractive power; a second lens unit with a positive refractive power; and a third lens unit with the positive refractive power, the first, second, and third lens units moving to perform zooming. The first lens unit includes a first lens element with the negative refractive power, and a second lens element with the positive refractive power in order of from the object side toward the image side, and in which a refractive index of a material of the first lens element (N), an Abbe number of a material of the second lens element (ν), and the radii of curvatures of lens surfaces of the first lens element on the object side and the image side (R, R) are appropriately set.