Imaging lens system

Patent metadata

Field	Value
Publication number	US-9116325-B2
Application number	US-201313893806-A
Country	US
Kind code	B2
Filing date	May 14, 2013
Priority date	May 14, 2012
Publication date	Aug 25, 2015
Grant date	Aug 25, 2015

Abstract

An imaging lens system includes, from the object side, an aperture stop, a positive first lens convex to the object side, a negative second lens, a positive third lens convex to the object side, a positive meniscus fourth lens convex to the image side, and a negative biconcave fifth lens, and fulfills the conditional formulae 0.8<f/f1<1.30, 0.5<f4/f1<0.90, 0.6<d4/d3<2.0, and 0.80<R3_1/f<2.20, where f is the focal length of the entire imaging lens system, f1 and f4 are the focal lengths of the first and fourth lenses, d3 is the axial thickness of the second lens, d4 is the axial aerial distance between the second and third lenses, and R3_1 is the radius of curvature of the object-side surface of the third lens on the optical axis.

First claim

What is claimed is:

1. An imaging lens system for imaging a subject image on an image sensing surface of an image sensing device, the imaging lens system comprising, from an object side:
an aperture stop;
a first lens element having a positive optical power and convex to the object side;
a second lens element having a negative optical power;
a third lens element having a positive optical power and convex to the object side;
a fourth lens element having a positive optical p…

Assignees

• Konica Minolta Inc

Inventors

• Yamada Keiko

Classifications

• G02B13/0045 Primary

  Physics · mapped topic

• G02B9/60 Primary

  Physics · mapped topic