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:
May. 18, 1982
Filed:
Jul. 11, 1980
Sadao Okudaira, Ranzan, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A compact zoom lens covering a range from standard to telephoto and having a high zoom ratio of approximately four adapted for use with 35 mm SLR cameras. The zoom lens system includes a first convergent lens group, a divergent lens group and a second convergent lens group in that order from the object. The first convergent lens group includes three lens components including at least one negative lens component, the divergent lens group is composed of at least three lens components including at least one positive lens component while the second convergent lens group includes at least two negative and two positive lens components with the last lens component being a negative lens the surface of smaller radius of curvature of which is directed to the object. The first and second convergent lens groups may be either rigidly coupled to be movable together or movable independently from one another to vary the overall focal length of the zoom lens system.