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. 23, 1991
Filed:
Aug. 08, 1988
Kazuyoshi Hata, Osaka, JP;
Minolta Camera Kabushiki Kaisha, Osaka, JP;
Abstract
A compact zoom lens system comprising from the object side to the image side, a first lens unit of a negative refractive power having a cemented lens component consisting of a negative lens element and a positive lens element cemented with each other, said first lens unit being shiftable along an optical axis of the lens system in zooming operation, a second lens unit of a positive refractive power having two positive lens components, at least one of which consists of a positive lens element and a negative lens element cemented with each other, said second lens unit being shiftable along the optical axis of the lens system in the zooming operation and a third lens unit of a positive refractive power having from the object side, a front lens component of a negative refractive power and a rear lens component of a positive refractive power, said third lens being stationary along the optical axis of the lens system in the zooming operation, in order to realize a zooming ratio of about two or three, a very short overall length and a light weight while having a large aperture by a configuration with a small number of lens elements.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile