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:
May. 05, 2020
Filed:
Apr. 26, 2018
Canon Kabushiki Kaisha, Tokyo, JP;
Masaru Sakamoto, Utsunomiya, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
Provided is a zoom lens including, in order from an object side to an image side: a first lens unit having a negative refractive power and configured not to move for zooming; a second lens unit having a positive refractive power and configured to move to an object side for zooming from a wide angle end to a telephoto end; and a rear lens unit arranged closest to the image side, wherein the rear lens unit includes an optical element having a positive refractive power and cemented with a lens made of a glass material, and wherein the optical element satisfies the following conditions:−2.100×10+0.693<θ; and0.555<θ<0.900,where νdm and θgFm are expressed by the following expressions:ν=(−1)/(); andθ=()/(),where Ng, NF, Nd and NC respectively represent refractive indices with respect to a g-line, an F-line, a d-line, and C-line.