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:
Apr. 24, 2001
Filed:
Feb. 25, 2000
Tomohiro Saito, Kawaguchi, JP;
Isamu Kaneko, Kawaguchi, JP;
Enplas Corporation, Saitama, JP;
Abstract
An image pickup lens system includes a first lens which is a concave lens having those radii of curvature of faces at the center thereof, which are not of the same sign, and a second lens which is a convex lens. The first face of at least the first lens is formed into an aspherical shape. The focal length of the entire lens system is set in a range of from 0.67 times the back focal length to 1.45 times the back focal length, and the focal length of the second lens is set in a range of 0.25 times the focal length of the first lens to 0.8 times the focal length of the first lens. Thus, it is possible to ensure the back focal length, while shortening the focal length of the image pickup lens system, and to easily produce the image pickup lens system.