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:
Jul. 02, 1991
Filed:
Mar. 22, 1990
Shuichi Kikuchi, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A zoom finder of a real image type comprises an objective lens composed of a first lens group having a positive refracting power, a second lens group having a negative refracting power, and a third lens group having a positive refracting power, the objective lens having a positive refracting power as a whole; an eyepiece composed of a fourth lens group having a positive refracting power; a device for forming a real image by the objective lens between the third and fourth lens groups and observing this real image through the eyepiece; and a device for increasing the magnification of the finder by moving the second lens group from an object side to an eyepiece side. The change is diopter of the finder caused by a zooming operation in the movement of the second lens group is corrected by displacing the first and third lens groups.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile