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:
Jan. 07, 1992
Filed:
Apr. 16, 1990
Tsutomu Toyono, Yokohama, JP;
Masamichi Tateoka, Yokohama, JP;
Yoshihiro Takada, Yokohama, JP;
Hisashi Fukushima, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A projecting apparatus comprises support device for supporting an original, a projection optical system for forming the image of the original, an optical element disposed on the image side of the projection optical system to cause a principal light ray having entered from the original through the projection optical system to travel in parallelism to the optic axis of the projection optical system, and control device for varying the imaging magnification of the original by the projection optical system with the spacing between the exit pupil of the projection optical system and the optical element being kept constant.