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:
Aug. 15, 2000
Filed:
Sep. 17, 1999
Takaaki Yano, Hokkaido, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An eyepiece optical system includes the first lens group constituted by a negative single meniscus lens element having a convex surface on the side of a user's eye, and the second lens group having positive power as a whole, in this order from the object, whereby an intermediate image formed by an objective optical system is positioned between the first lens group and the second lens group. The second lens group includes a positive single meniscus lens element having a convex surface on the side of a user's eye, and a cemented sub-lens group having positive power as a whole. The cemented sub-lens group includes a positive lens element and a negative lens element. Furthermore, the eyepiece optical system satisfies the following conditions: