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:
Jun. 26, 2007
Filed:
Sep. 05, 2006
Shinichiro Yakita, Utsunomiya, JP;
Shinichiro Yakita, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens in which a precise focus detection signal can be detected while a user can observe an image to be shoot without being affected by insertion/removal of an extender lens into an optical axis. A relay lens unit stationary during zooming includes lens unit Lincluding a branch element, lens unit Linterchangeable with extender lens unit insertable into/removable from optical path to change focal length range of the entire system and positive lens unit Lin order from object side to image side, and the zoom lens satisfies specific conditions among distance from an aperture stop to front principal point of L, distance from rear principal point of Lto front principal point of L, distance from rear principal point of Lto front principal point of L, refractive power of L, and refractive power of the entire system of the zoom lens at wide-angle end.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile