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:
Apr. 26, 2011
Filed:
Jun. 27, 2008
Yasuhiro Kondo, Nagoya, JP;
Yasuhiro Kondo, Nagoya, JP;
Elmo Company, Limited, , JP;
Abstract
In the zoom lens, the second lens group includes at least one surface that is an aspheric surface, and during changing magnification, the second lens group, the third lens group, and the fourth lens group are respectively capable of moving independently, with the position of the aperture moving along a convex trajectory on the optical axis from the image side to the object side during changing magnification. Through operation in this manner, the zoom lens of the invention is inexpensive and compact, and efficiently corrects various types of aberration. Thus, at a high magnification ratio of 5× or greater, the zoom lens of the invention affords a wide field exceeding approximately 78 degrees at the wide angle end, and affords a high performance compact zoom lens whose distortion is held to 3% or less.