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:
Oct. 02, 1979
Filed:
Dec. 20, 1977
Soichi Nakamura, Kamakura, JP;
Nippon Kogaku K.K., Tokyo, JP;
Abstract
The wide-angle zoom lens system comprises a divergent lens group and a convergent lens group in the order from the object side, both of the lens groups being movable on the optical axis of the lens system to vary the air space between the two groups so that the magnification of the image is variable while the image plane is being maintained at a fixed position. The divergent lens group includes four air-spaced components which are, in the order from the object side, a first positive component with the more curved surface facing the object side, a first negative component with the more curved surface facing the image side, a second negative component with the more curved surface facing the image side and a first positive meniscus component convex to the object side. The first positive component and the first negative component define therebetween an air chamber having convergent power. The first negative component and the second negative component define therebetween an air chamber having divergent power with its more curved surface facing the object side. The axial space between the second negative component and the first positive meniscus component is greater than the space between the first positive component and the first negative component. The convergent lens group includes at least four positive components and a negative component intervening among the positive components, all components being separated from one another.