US RE48,364 E1 · Imaging lens

Abstract

An imaging lens includes: an aperture stop; a biconvex first lens directing convex surfaces toward an object and an image; a second lens directing a convex surface toward the object near the optical axis and having negative refractive power; a biconvex third lens directing convex surfaces toward the object and the image near the optical axis; a fourth lens directing a concave surface toward the object near the optical axis and having positive refractive power; and a fifth lens directing a convex surface toward the object near the optical axis and having negative refractive power. The aperture stop and the first to fifth lenses are arranged in this order from the object side, and a conditional expression 1 being 0.50<f1/f<0.76 is satisfied, where f1 represents the focal length of the first lens and f represents the focal length of the entire imaging lens.

Claims28

Dependent claims

An imaging lens for use in solid-state image sensors, comprising:

an aperture stop;
a biconvex first lens directing convex surfaces toward an object side and an image side;
a second lens directing a convex surface toward the object side near an optical axis and having negative refractive power;
a biconvex third lens directing convex surfaces toward the object side and the image side near the optical axis;
a fourth lens directing a concave surface toward the object side near the optical axis and having positive refractive power;
and
a fifth lens directing a convex surface toward the object side near the optical axis and having negative refractive power, wherein
the aperture stop and the first to fifth lenses are arranged in this order from the object side of the imaging lens toward an image surface thereof, and
a conditional expression 1 is satisfied, the conditional expression 1 being 0.50<f1/f<0.76 where f1 represents the focal length of the first lens and f represents the focal length of the entire imaging lens.

6 more elements

An imaging lens for use in solid-state image sensors, comprising:

an aperture stop;
a first lens having a convex surface on an object side and having positive refractive power;
a second lens having negative refractive power;
a third lens having a convex surface on an image side near an optical axis, and having two aspheric surfaces;
a fourth lens having a convex surface on the image side near the optical axis, having two aspheric surfaces, and having positive refractive power;
and
a meniscus-shaped fifth lens having a convex surface on the object side near the optical axis, having two aspheric surfaces, and having negative refractive power, wherein
the aperture stop and the first to fifth lenses are arranged in this order from the object side of the imaging lens toward an image surface thereof, and
conditional expressions 2 and 10a are satisfied, the conditional expressions 2 and 10a being −0.80<(r5+r6)/(r5−r6)<0.55, and 2.0≤f/EPD≤2.6 where r5 represents the curvature radius of the object side surface of the third lens;
r6 represents the curvature radius of the image side surface thereof;
EPD represents the diameter of the aperture stop;
and f represents the focal length of the entire imaging lens.

9 more elements

Dependencies are inferred from the claim text.

Imaging lens

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Imaging lens

Life of this patent

Abstract

Claims28