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:
Jul. 11, 2000
Filed:
Feb. 12, 1999
Kazunori Ohno, Omiya, JP;
Fuji Photo Optical Co., Ltd., Omiya, JP;
Abstract
A wide-angle zoom lens is disclosed having four lens groups of negative, positive, positive, and positive refractive power, in order from the object side. By satisfying prescribed conditions, the overall length as well as the outer diameter of the wide-angle zoom lens can be kept small, the number of lens elements required can be minimized so as to keep manufacturing costs low, yet a high-quality image is provided over the entire range of zoom. During zooming, the first and fourth lens groups remain in a fixed position while the second and third lens groups are moved along the optical axis. The first lens group G.sub.1 includes at least one negative lens element with a concave surface of strong curvature on the image side. The second lens group G.sub.2 has at least one biconvex lens. The third lens group G.sub.3 may consist of a single positive lens. The following conditions are satisfied: