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:
Nov. 07, 2006
Filed:
Jun. 06, 2005
Motoyuki Otake, Saitama, JP;
Motoyuki Otake, Saitama, JP;
Sony Corporation, , JP;
Abstract
A varifocal zoom lens includes: a first lens group having a negative refractive power; a second lens group having a positive refractive power, including a cemented lens component Lformed by combining a positive lens having a convex surface on the object side and a negative lens having a concave surface on an image side and a positive lens component Ldisposed on the image side with respect to the cemented lens component L, spaced from the cemented lens component Lby an air space and having a convex surface on the object side and disposed behind the first lens group with respect to an object side; and a third lens group having a positive refractive power and disposed behind the second lens group with respect to the object side. At least the first and the second lens group are moved and the second lens group is moved toward the object side so as to decrease an interval between the first and the second lens group, when a lens state is changed from a shortest-focal-length lens state to a longest-focal-length lens state, an aperture stop is disposed between the first and the second lens group, and the second lens group includes and satisfies conditions expressed by:0.02</()<0.1  (1)0.6<<0.8  (2)where Dis the length of an air space between the cemented lens component Land the positive lens component L, Ris the radius of curvature of the surface on the object side of the positive lens component L, Ris the radius of curvature of the surface on the image side of the cemented lens component L, and Dis the distance between the aperture stop and the surface on the image side of the cemented lens component L