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:
Oct. 04, 2005
Filed:
Jul. 30, 2003
Sawako Chatani, Port Washington, NY (US);
Katsumi Kurematsu, Tokyo, JP;
Takayuki Ishii, Tokyo, JP;
Toshihiro Sunaga, Tokyo, JP;
Yoshiaki Kurioka, Tokyo, JP;
Sawako Chatani, Port Washington, NY (US);
Katsumi Kurematsu, Tokyo, JP;
Takayuki Ishii, Tokyo, JP;
Toshihiro Sunaga, Tokyo, JP;
Yoshiaki Kurioka, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A projection optical system which has a short projection distance and a compact structure, and allows oblique projection. The projection optical system projects luminous flux from an image forming element for forming an original image onto a projection surface which is oblique to a central principal ray which is a principal ray of luminous flux traveling from the center of the original image to the center of a finally formed image. The system includes a plurality of reflecting surfaces each having a curvature. In addition, the projection optical system satisfies a predetermined expression (1).