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. 21, 2016
Filed:
Sep. 16, 2013
Canon Kabushiki Kaisha, Tokyo, JP;
Hideki Sakai, Sakura, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, and a fourth lens unit having a positive refractive power. Each lens unit moves so that a distance between adjacent lens units changes during zooming. The third lens unit includes a positive lens Gclosest to the image side which has a concave meniscus surface on an image side. A conditional expression 0.03<R3i2/ft<0.25 is satisfied where R3i2 is a radius of curvature of a lens surface on the image side of the positive lens G, and ft is a focal length of the overall system at a telephoto end.