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:
Dec. 15, 2009
Filed:
Mar. 18, 2008
Yoshihito Souma, Sakai, JP;
Yoshihito Souma, Sakai, JP;
Konica Minolta Opto, Inc., Hachioji-shi, JP;
Abstract
A zoom optical system includes first through fourth lens groups having negative-positive-negative-positive optical powers. Assuming that a curvature radius of an object-side lens surface of a negative lens element in the first lens group is r, a curvature radius of an image-side lens surface of the negative lens element in the first lens group is r, a focal length of the third lens group is f, a focal length of the entirety of the optical system at the wide angle end is fw, a focal length of the entirety of the optical system at the telephoto end is ft, and an average refractive index of positive lens elements in the second lens group is nd, the zoom optical system satisfies the conditional expressions:0<(1+2)/(1−2)<1.0−0.9<3/√{square root over ( )}()<−0.41.6<ndp2.