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. 05, 2011
Filed:
Jan. 08, 2010
Motoyuki Ohtake, Saitama, JP;
Motoyuki Ohtake, Saitama, JP;
Sony Corporation, Tokyo, JP;
Abstract
A variable-focal-length lens system includes first to fifth lens groups having positive, negative, positive, negative, and positive refractive powers, respectively, from the object side. As the lens-position state changes from wide-angle to telephoto, the air space between the first and second lens groups increases, the air space between the second and third lens groups decreases, the air space between the third and fourth lens groups changes, the air space between the fourth and fifth lens groups increases, the first lens group moves monotonously toward the object, the second lens group is fixed in the optical-axis direction, and the third and fourth lens groups move toward the object. Conditions 0.2<D/ft<0.4, 0.1<f/f<0.4 are satisfied, D, ft, and fand fbeing the air space between the second and third lens groups at wide-angle, lens system's overall focal length at telephoto end, and focal lengths of the second and fourth lens groups, respectively.