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. 06, 2010
Filed:
Jan. 13, 2009
Takahiro Amanai, Shibuya-ku, JP;
Akio Michinaka, Shibuya-ku, JP;
Hisashi Goto, Shibuya-ku, JP;
Olympus Corporation, Tokyo, JP;
Abstract
A wide-angle optical system comprises, in order from its object side, a stop, a first lens (L) having positive refracting power, a second lens (L) having negative refracting power and a third lens (L) that is an aspheric lens. The third lens is configured such that as viewed in a lens section including an optical axis, a portion thereof near the optical axis is in a meniscus shape convex on an object side thereof, and an object side surface and an image side surface thereof at a peripheral site are in a meniscus shape convex on an image side thereof. The optical system satisfies the following conditions (1-1) and (1-2).−0.40<3<0.15  (1-1)0.30<7/7<2.0  (1-2)where f is the focal length of the whole wide-angle optical system, and fis the focal length of the third lens. When Lm stands for a light ray passing through the center of the stop at an angle of 36° with the optical axis, and Pmstands for a point at which Lm passes the image side surface of the third lens, hcis supposed to be a distance from Pmto the optical axis, and hpis supposed to be a distance from a convex apex Ppof the image side surface of the third lens to the optical axis.