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:
Feb. 05, 1985
Filed:
Apr. 13, 1982
Kiyoshi Hayashi, Yokohama, JP;
Nippon Kogaku K.K., Tokyo, JP;
Abstract
A zoom lens comprises, in succession from the object side, a convergent first lens unit stationary during zooming and moved on the optical axis during focusing, a divergent second lens unit which is a variator moved on the optical axis during zooming, a divergent third lens unit which is a compensator moved on the optical axis during zooming, and a convergent fourth lens unit as a master lens system stationary during zooming. The fourth lens unit comprises, in succession from the object side, a convergent first master lens unit, a convergent second master lens unit and a divergent third master lens unit. The first master lens unit has, in succession from the object side, a positive lens, a positive and a negative lens cemented to each other in a cemented surface concave toward the object side, a positive lens having its surface of greater curvature facing the object side, and a negative lens having its surface of greater curvature facing the image side. The second master lens unit has a biconvex single lens, and the third master lens unit has at least one negative lens and a positive lens.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile