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 distance lens system includes a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power, which are sequentially disposed from an object side to an image side. The system satisfies −0.65<(R33−R34)/(R33+R34)<−0.25 and −1.0<(R22−R23)/(R22+R23)<−0.6, wherein R33 represents the radius of curvature of the most image-side surface of a cemented lens of the third lens group, R34 represents the radius of curvature of the object-side surface of a positive lens of the third lens group disposed on the most image side, R22 represents the radius of curvature of the image-side surface of a negative lens of the second lens group disposed on the most object side, and R23 represents the radius of curvature of the most object-side surface of a cemented lens of the second lens group.