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:
May. 25, 1976
Filed:
Jan. 27, 1975
Yutaka Sakai, Omiya, JA;
Fuji Photo Optical Co., Ltd., Omiya, JA;
Abstract
A retrofocus type lens system particularly useful for single lens reflex cameras. The back focal distance is 1.56 times as long as the effective focal length of the lens system and the angle of view is as large as 84.degree.. The aperture ratio is as large as F/2.8 and all aberrations are well corrected. The lens system comprises a positive meniscus lens L1, two negative meniscus lenses L2 and L3 convex to the front, a positive meniscus lens or plano-convex lens L4 convex to the rear, a biconvex lens L5, a cemented negative lens component consisting of a biconcave lens L6 and a positive meniscus lens L7, a positive meniscus lens L8 convex to the rear, and a positive lens L9.