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. 30, 2013
Filed:
Jul. 23, 2008
Keiki Yoshitsugu, Hyogo, JP;
Katsu Yamada, Osaka, JP;
Shunichiro Yoshinaga, Hyogo, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A zoom lens system according to the present invention, from an object side, comprises a first lens unit having positive optical power, a second lens unit having negative optical power, a third lens unit having positive optical power, and a fourth lens unit having positive optical power. In zooming, the first to the fourth units all move along the optical axis. The third lens unit is composed of three or more lens elements. The condition (6): nd≦1.5 and vd≧75 and the condition (7): (nd−1)+(nd−1)≧1.55 are satisfied (where, 16<f/f, ω>35, and in the third lens unit: nd, nd, ndare refractive indices to the d-line of the lens elements located on the most object side and at the second and the third positions from the object side; vdis an Abbe number to the d-line of the lens element on the most object side; ω is a half view angle at a wide-angle limit; fis a focal length of the entire system at a telephoto limit; and fis a focal length of the entire system at a wide-angle limit). As a result, the zoom lens system has a reduced size and still realizes a wide view angle at a wide-angle limit, as well as a remarkably high zooming ratio and high performance.