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:
Dec. 04, 1990
Filed:
Feb. 27, 1989
Asahi Kogaku-Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical device for varying magnification, having an object plane on which an object is to be located, a light receiving surface, and an imaging lens unit for focusing an image of the object located on the object plane onto the light receiving surface, so that upon varying the magnification, an optical distance between the object plane and the light receiving surface can be changed, wherein the imaging lens unit includes a main lens group and a correcting lens group that are movable relative to each other, the main lens group or the correcting lens group being fixed with respect to the light receiving surface, the correcting lens group or the main lens group being movable to the object plane and the light receiving surface to vary the magification.