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:
Mar. 04, 2008
Filed:
Sep. 26, 2005
Mamoru Terada, Sakai, JP;
Toru Nakatani, Sakai, JP;
Mamoru Terada, Sakai, JP;
Toru Nakatani, Sakai, JP;
Konica Minolta Photo Imaging, Inc., Tokyo, JP;
Abstract
A variable magnification optical system for forming an optical image of an object on a light-receiving surface of an image sensor with variable magnification includes: from the object side, at least a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit having a positive optical power, and a fourth lens unit having a positive optical power. In magnification variation from the wide angle end to the telephoto end, at least the first lens unit moves. Conditional formulae (1) and (2) below are fulfilled: (1) 6.0<fl/fw<20.0 and (2) 1.83<Nd, where fl represents the focal length of the first lens unit, fw represents the focal length of the entire system at the wide angle end, and Ndrepresents the average refractive index for a d-line among all lens elements included in the second lens unit.