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:
Feb. 04, 1997
Filed:
Dec. 16, 1994
Toshihiko Ueda, Toyokawa, JP;
Hiroki Kinoshita, Toyokawa, JP;
Minolta Co., Ltd., Osaka, JP;
Abstract
A copying zoom lens system is provided with from the original side a first lens unit of negative refractive power including at least one negative lens element, a second lens unit of positive refractive power including at least four lens elements, and a third lens unit of negative refractive power including at least one negative lens element. The second lens unit is asymmetric with respect to the center of the lens units of the lens system. During zooming, the projection magnification is varied with the conjugate distance being maintained constant by varying the distance between the first and second lens units and the distance between the second and third lens units and by moving the entire lens system. The axial distances among the lens units are defined by predetermined conditions.