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. 04, 2018
Filed:
Oct. 10, 2017
Canon Kabushiki Kaisha, Tokyo, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
The present invention provides a projection optical system including a first concave reflecting surface, a first convex reflecting surface, a second concave reflecting surface, and a third concave reflecting surface, wherein the first concave reflecting surface, the first convex reflecting surface, the second concave reflecting surface, and the third concave reflecting surface are arranged such that light from an object plane forms an image on an image plane by being reflected by the first concave reflecting surface, the first convex reflecting surface, the second concave reflecting surface, the first convex reflecting surface, and the third concave reflecting surface in an order named.