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. 06, 2015
Filed:
Apr. 12, 2013
Canon Kabushiki Kaisha, Tokyo, JP;
Tomoyuki Nakamura, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
In a zoom lens including a positive first lens unit, negative second lens unit, positive third lens unit, and positive fourth lens unit, the fourth lens unit includes a 41 lens group, a 42 lens group, and a 43 lens group. the lateral magnification of the third lens unit at a wide-angle end when an infinite object is focused, the focal length of the fourth lens unit, the lens configuration length of the fourth lens unit, the air interval between the 41 and 42 lens groups, the air interval between the 42 and 43 lens groups, the focal length of the 42 lens group, the average values of the Abbe constants and partial dispersion ratios of positive lens of the 42 lens group, the average values of the Abbe constants and partial dispersion ratios of negative lenses of the 42 lens group, and the like are appropriately set.