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:
Sep. 25, 2018
Filed:
Dec. 12, 2016
Applicant:
Canon Kabushiki Kaisha, Tokyo, JP;
Inventor:
Hiroto Yasui, Saitama, JP;
Assignee:
CANON KABUSHIKI KAISHA, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 27/44 (2006.01); G02B 13/00 (2006.01); G02B 5/18 (2006.01); G02B 7/02 (2006.01); G02B 7/08 (2006.01); G02B 9/14 (2006.01); G02B 27/00 (2006.01); G02B 27/42 (2006.01); G02B 27/64 (2006.01);
U.S. Cl.
CPC ...
G02B 13/0045 (2013.01); G02B 5/1847 (2013.01); G02B 5/1876 (2013.01); G02B 7/021 (2013.01); G02B 7/08 (2013.01); G02B 9/14 (2013.01); G02B 27/0025 (2013.01); G02B 27/4205 (2013.01); G02B 27/646 (2013.01);
Abstract
An optical system includes a diffractive surface and at least one aspherical surface, an aspherical surface of at least one aspherical surface closest to the diffractive surface is referred to as a first aspherical surface, a phase function ψ(r) and an aspherical function X(r) of the first aspherical surface increase with different signs from each other in a height direction with increasing a distance from an optical axis, and a condition below is satisfied: where f is a focal length of the optical system when focusing on an infinite object, and Fno is an F number of the optical system.