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:
May. 24, 2011
Filed:
Oct. 15, 2009
Koji Hoshi, Yokohama, JP;
Koji Hoshi, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens comprises, from object to image side: a positive first-lens unit; a negative second-lens unit; a positive third-lens unit; and a positive fourth-lens unit; the third-lens unit comprising a negative 3a'th-lens sub-unit and positive 3b′th-lens sub-unit from object side; the second-lens unit and fourth-lens unit moving on the optical axis during zooming; the 3b′th-lens sub-unit moving in a direction perpendicular to the optical axis, thereby displacing an image perpendicular to the optical axis; the 3a′th-lens sub-unit comprising a negative-lens element Gwhose both surfaces are spherical, and a positive-lens element whose both surfaces are spherical; the 3b′th-lens sub-unit including a positive-lens element Gincluding an aspherical lens surface, and a negative-lens element; wherein, assuming that the indices of the materials of the negative-lens element Gand the positive-lens element Gare NGand NGrespectively, 0.21<NG−NGis satisfied.