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:
Mar. 21, 1978
Filed:
Apr. 28, 1976
Kyozo Uesugi, Izumi, JA;
Mitsuo Yasukuni, Sakai, JA;
Minolta Camera Kabushiki Kaisha, Osaka, JA;
Abstract
The present lens system is capable of providing not only a zooming function over a relatively wide range, but also macrophotography. The zoom lens system includes a first lens group capable of varying the focal length without a loss of focus and a second lens group forming a master lens group. The second lens group is spatially displaced on the image side of the first lens group and includes a lens component movably mounted on the optical axis of the system that is capable of varying the focal length of the second lens group. The movable lens component in the second lens group has two positions which will provide the same final image plane for the entire zoom lens system, for example, a forward and backward position does not introduce any image plane deviations and permits an extension of the zoom range of the total lens system. The intermediate position of the movable lens component of the second lens group can be utilized for focusing in a macrophotography range. Thus the movable lens component has the capability of providing an exaggerated image plane deviation between its forward and backward position to permit macrophotography with the lens system.