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:
Apr. 29, 1986
Filed:
Apr. 25, 1984
Masamichi Tateoka, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
This specification discloses a projection lens for projecting an original onto the surface of a sensor and for use in a facsimile apparatus or a digital copying apparatus. The projection lens enables the image of the original to be projected onto the sensor at different projection magnifications with the length of the optical path between the surface of the original and the sensor kept constant. The projection lens comprises, in succession from the object side, a first lens group comprising a negative meniscus lens having its convex surface facing the object side, and a positive meniscus lens having its convex surface facing the object side, the first lens group as a whole having a negative refractive power, and a second lens group having three positive lenses and a negative lens, the second lens group as a whole having a positive refractive power. The first lens group is stationary and the second lens group is movable, whereby the image of the original is projected onto the surface of the sensor at different projection magnifications with the object-image distance being kept constant.