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.

Date of Patent:
Jun. 02, 2009

Filed:

May. 22, 2007
Applicants:

Koji Toyoda, Kanagawa, JP;

Yusuke Nanjo, Kanagawa, JP;

Shinichi Arita, Tokyo, JP;

Inventors:

Koji Toyoda, Kanagawa, JP;

Yusuke Nanjo, Kanagawa, JP;

Shinichi Arita, Tokyo, JP;

Assignee:
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G02B 15/14 (2006.01);
U.S. Cl.
CPC ...
Abstract

A zoom lens includes in order and from the side of an object, a first lens group having a positive refractive power and fixed in position, a second lens group having a negative refractive power and movable in position for providing mainly zooming, a third lens group having a positive refractive power and fixed in position, a fourth lens group having a positive refractive power and movable in position for performing a focal position correction due to the zooming and for focusing, and a fifth lens group including a single lens fixed in position. Each of the lens groups from the third lens group to the fifth lens group has at least one aspheric surface, and conditional equations (1) and (2) below are satisfied.|4/5|<0.12  (3)0.9<β5<1.2  (4)where f4 is a focal length of the fourth lens group, f5 is a focal length of the fifth lens group, and β5 is a transverse magnification of the fifth lens group.


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