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:
Oct. 24, 2017
Filed:
Sep. 14, 2016
Canon Kabushiki Kaisha, Tokyo, JP;
Tomoya Yamada, Utsunomiya, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
A zoom lens includes in order from an object side, a zoom lens unit that moves during zooming, and an aperture stop; and a relay lens unit that does not move for zooming, and the relay lens unit includes an extender lens unit changing a focal length range of the zoom lens by entering into and leaving from an optical path of the zoom lens, and that unit includes front, middle, and rear lens sub-units each including one positive lens and one negative lens. The following expressions are satisfied:0.250<||<0.200; and||<0.200,where Np and fbp denote a refractive index and a focal length of the positive lens, Nn and fbn denote a refractive index and a focal length of the negative lens, and fb denotes a focal length of the middle lens sub-unit.