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:
Jul. 13, 2021
Filed:
Jul. 10, 2019
Applicant:
Canon Kabushiki Kaisha, Tokyo, JP;
Inventors:
Tomoya Yamada, Utsunomiya, JP;
Shoichi Takemoto, Saitama, JP;
Assignee:
CANON KABUSHIKI KAISHA, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 15/20 (2006.01); G02B 27/00 (2006.01); G02B 13/18 (2006.01);
U.S. Cl.
CPC ...
G02B 15/20 (2013.01); G02B 27/005 (2013.01); G02B 13/18 (2013.01);
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 and configured to move for zooming; and at least one lens unit configured to move for zooming. The distance between each pair of the lens units adjacent to each other is changed for zooming. The first lens unit includes a negative lens and an Abbe number and a partial dispersion ratio of the negative lens are properly determined.