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:
Aug. 08, 2006
Filed:
Apr. 25, 2005
Hiroyuki Hamano, Koga, JP;
Hiroshi Saruwatari, Utsunomiya, JP;
Hiroyuki Hamano, Koga, JP;
Hiroshi Saruwatari, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens system including, in order from an object side to an image side, a first lens unit of positive optical power, and a second lens unit of negative optical power, followed by a lens component having a lens unit, wherein at least one of the first lens unit and the second lens unit moves during zooming. One of the lens units of the zoom lens system includes a layer made of a material that satisfies the following conditions:11<νIT<270.2<θIT<0.4.Wherein νIT is an Abbe number of the layer, and θIT is a partial dispersion ratio for the g-spectral line and f-spectral line of the layer. The layer has an optical power of a sign opposite to that of the lens unit including the layer.