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. 22, 1992
Filed:
Feb. 08, 1991
Yasuzi Ogata, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A variable magnification viewfinder comprising, in the order from the object side, an objective lens system having a positive refractive power, a field lens component having a positive refractive power and an eyepiece lens system having a positive refractive power; said objective lens system comprising a first lens unit having a negative refractive power, a second lens unit having a positive refractive power and a third lens unit having a negative refractive power, and said variable magnification lens system being designed in such a manner that it performs variation of magnification and correction of diopter by moving said second lens unit and said third lens unit along the optical axis so as to vary the airspace reserved between these lens units with said first lens unit kept fixed on the optical axis. The variable magnification viewfinder has a variable magnification ratio on the order of 2, a compact design and favorably corrected aberrations, and can be manufactured at a low cost in practice.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile