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. 04, 2006
Filed:
Apr. 10, 2003
Yoshito Miyatake, Neyagawa, JP;
Keiki Yoshitsugu, Sakai, JP;
Yoshito Miyatake, Neyagawa, JP;
Keiki Yoshitsugu, Sakai, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
It is an object to provide a zoom lens made of three groups having a zoom ratio of ×2.5 to ×3.2 if the object distance is ∞, an field angle at the wide-angle end of 60° to 70°, high resolution, and a short optical total length when not in use. The zoom lens is made of a first lens group (G) with a negative power, a second lens group (G) with a positive power, and a third lens group (G) with a positive power, arranged in that order from an object side to an image plane (S) side. The first lens group (G) is made of a first lens (L) that is a negative meniscus lens whose surface with strong curvature is facing the image plane (S) side and a second lens (L) that is a positive meniscus lens whose surface with strong curvature is facing the object side, arranged in that order from the object side. The second lens group (G) is made of a third lens (L) that is a positive lens whose convex surface is facing the object side, a fourth lens (L) that is a positive lens, a fifth lens (L) that is a negative lens, and a sixth lens (L) that is a plano-convex lens whose convex surface is facing the image plane (S) side, arranged in that order from the object side. The third lens group (G) is made of a single seventh lens (L) that is a positive lens.