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. 18, 1986
Filed:
Aug. 25, 1983
Takayuki Itoh, Tokyo, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens with a high variable power ratio including wide-angle lens capability, comprises, in order from the object, a first lens unit having a positive focal length, a second lens unit having a negative focal length, and a third lens unit having a positive focal lenth. The first, second and third lens units are mechanically movable to change the overall focal length and keep an image plane constant. The third lens unit is composed of, in order from the object, a third sub-lens unit a having a positive lens, a negative lens and a positive lens in order from the object and a third sub-lens unit b having a positive lens, a negative lens and a positive lens in order from the object.