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. 13, 2010
Filed:
Nov. 21, 2008
Noriyuki Iyama, Hachioji, JP;
Noriyuki Iyama, Hachioji, JP;
Olympus Imaging Corp., Tokyo, JP;
Abstract
An image forming optical system comprises, in order from an object side, a front lens group having negative refracting power, and a rear lens group having positive refracting power, wherein said front group comprises, in order from the object side, a first lens element having the negative refracting power, and a second lens element of a meniscus form having a convex surface directed toward an image side; wherein said first lens element has an aspherical surface that is a concave surface directed toward the object side in the vicinity of the optical axis, and negative refracting power at a position on the aspherical surface becomes weak as a distance between the position and the optical axis becomes large, and a surface directed toward the image side that is concave at least in the vicinity of the optical axis; and further the following conditions (1) and (2) are satisfied:1.0<|<10  (1)1.0<<10  (2)where Fis a focal length of the whole optical system, fis a focal length of said front group, and fis a focal length of said rear group.