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:
Sep. 14, 2004

Filed:

Dec. 26, 2002
Applicant:
Inventor:

Katsuhisa Tsutsumi, Kawagoe, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02C 1/304 ;
U.S. Cl.
CPC ...
G02C 1/304 ;
Abstract

A retrofocus wide-angle lens is formed of only three lens groups, in order from the object side, a first lens group of negative refractive power, a second lens group that includes a stop, and a third lens group of positive refractive power. The first lens group is at the object end of the retrofocus wide-angle lens and includes, in order from the object side, a plurality of negative lens components and a plurality of positive lens components. The first lens group includes three lens groups with particular lens features, the first of which, from the object side, also includes two lens groups with particular features. Various combinations of lens elements satisfy two conditions for ratios of absolute values of focal lengths for the various combinations of lens elements that assist in achieving excellent imaging.


Find Patent Forward Citations

Loading…