Abstract: An imaging lens includes a first lens group having positive refractive power; a second lens group having negative refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having positive refractive power. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens having negative refractive power and a seventh lens.

Abstract: An imaging lens includes a first lens having negative refractive power; a second lens having positive refractive power; a third lens; and a fourth lens arranged in the order from an object side to an image plane side. The first lens has an image plane-side surface having a positive curvature radius. The first lens has a specific focal length to satisfy a specific conditional expression.

Abstract: A compact low-cost imaging lens which provides high brightness with an F-value of 2.5 or less and a wide field of view and corrects aberrations properly, meeting the demand for low-profile design. The imaging lens elements are arranged in the following order from an object side to an image side: an aperture stop; a first lens with positive refractive power having a convex surface on each of the object and image sides; a second lens with negative refractive power; a third lens with positive refractive power having a convex surface on each of the object and image sides; a fourth lens with negative refractive power; and a fifth lens with negative refractive power as a double-sided aspheric lens. The imaging lens satisfies a conditional expression (1) below: 1.5<f3/f<5.0??(1) where f: focal length of the overall optical system of the imaging lens f3: focal length of the third lens.

Abstract: An imaging lens includes a first lens; a second lens; a third lens; a fourth lens; and a fifth lens, arranged from an object side to an image plane side. The first lens is formed such that a curvature radius of a surface on the object side is positive. The third lens is formed such that a curvature radius of a surface on the object side is positive. The fourth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric. The fifth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric, and a curvature radius of the surface thereof on the image plane side is positive near an optical axis thereof. The first lens and the third lens have specific focal lengths.

Abstract: An imaging lens includes a first lens; a second lens; a third lens; a fourth lens; and a fifth lens, arranged from an object side to an image plane side. The first lens is formed in a shape so that a curvature radius of a surface on the object side is positive. The third lens is formed such that a curvature radius of a surface on the object side is positive. The fourth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric. The fifth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric, and a curvature radius of the surface on the image plane side is positive near an optical axis thereof. The fourth lens and the fifth lens have specific Abbe's numbers.

Abstract: An imaging lens includes a first lens having negative refractive power; a second lens having positive refractive power; a third lens having positive refractive power; and a fourth lens, arranged in this order from an object side to an image plane side. The second lens is arranged to face the third lens. The first lens has a focal length f1 and the fourth lens has an Abbe's number ?d4 so that the specific conditional expressions are satisfied.

Abstract: An imaging lens includes a first lens having at least one aspheric surface; a second lens having at least one aspheric surface; a third lens having at least one aspheric surface; a fourth lens having at least one aspheric surface; a fifth lens having at least one aspheric surface; a sixth lens having two aspheric surfaces; and a seventh lens having two aspheric surfaces, arranged in this order from an object side to an image plane side. The first lens is formed in a shape so that a surface thereof on the object side is convex near an optical axis thereof. The seventh lens is formed in a shape so that a surface thereof on the image plane side is concave near the optical axis thereof. The first lens and the sixth lens have specific Abbe's numbers.

Abstract: An imaging lens elements are arranged in order from an object side, an aperture stop, positive first lens having convex object-side and image-side surfaces, negative meniscus second lens having a concave image-side surface, positive third lens having at least one aspheric surface, positive double-sided aspheric fourth lens, and negative double-sided aspheric fifth lens having concave object-side and image-side surfaces with its image-side surface having a pole-change point off the axis. It satisfies conditional expressions below: 0.5<f1/f<1.0??(1) 10.0<f3/f??(2) 0.8<(r3+r4)/(r3?r4)<2.0??(3) where f: focal length of the imaging lens overall optical system f1: first lens focal length f3: third lens focal length r3: curvature radius of the second lens object-side surface r4: curvature radius of the second lens image-side surface.

Abstract: An imaging lens includes a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens, and a third lens. The second lens group includes a fourth lens having positive refractive power and a fifth lens having negative refractive power. The third lens group includes a sixth lens and a seventh lens having negative refractive power. The seventh lens is formed in a shape so that a surface thereof on the object side and a surface thereof on the image plane side have positive curvature radii. The surface of the seventh lens on the image plane side is formed in an aspheric shape having at least one inflexion point.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; a fourth lens having at least one aspheric surface; a fifth lens having at least one aspheric surface; a sixth lens having two aspheric surfaces; and a seventh lens having two aspheric surfaces, arranged in this order from an object side to an image plane side. The first lens is formed in a shape so that both surfaces are convex near an optical axis thereof. The fourth lens is formed in a meniscus shape so that a surface thereof on the object side is concave near the optical axis. The seventh lens is formed in a shape so that a surface thereof on the image plane side is concave near the optical axis.

Abstract: A compact low-priced imaging lens which offers a field of view of about 180 degrees and high optical performance. The imaging lens for a solid-state image sensor includes, in order from an object side to an image side, a first lens with negative refractive power having a convex object-side surface and an aspheric image-side surface; a second lens with negative refractive power as a double-sided aspheric lens having a concave surface on the image side; a third lens with positive refractive power; an aperture stop; and a fourth lens with positive refractive power. The first and second lenses are made of plastic material. The imaging lens satisfies conditional expressions (1) and (2) below: ?65.0<f1/f<?17.0??(1) 0.04<f2/f1<0.14??(2) where f: focal length of the overall optical system of the imaging lens f1: focal length of the first lens f2: focal length of the second lens.

Abstract: An imaging lens includes a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having negative refractive power. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens and a seventh lens. The first to third lenses have specific Abbe's numbers.

Abstract: An image pickup lens includes an aperture stop, a first lens with positive refractive power having a convex object-side surface, a second lens with negative refractive power having a concave image-side surface, a third lens with positive refractive power having a convex image-side surface, a fourth lens with negative refractive power as a double-sided aspheric lens having a concave object-side surface, and a fifth lens with negative refractive power of a meniscus shape as a double-sided aspheric lens having a concave image-side surface, wherein the fifth lens is designed so that the negative refractive power weakens as the distance from the optical axis increases, and wherein the following conditional expression (1) is satisfied: 0.55<f1/f<1.0??(1) where f represents a focal length of an overall image pickup lens, and f1 represents a focal length of the first lens.

Abstract: An imaging lens includes a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having positive refractive power, and a third lens having negative refractive power. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens having negative refractive power and a seventh lens having negative refractive power. The first lens, the second lens, the third lens, and the seventh lens have specific Abbe's numbers. The first lens and the second lens have specific focal lengths.

Abstract: An imaging lens includes a first lens having negative refractive power; a second lens; a third lens; a fourth lens having positive refractive power; and a fifth lens. The second lens has a surface on the object side formed in an aspheric shape. The first to fifth lenses are formed of materials having specific Abbe's numbers to satisfy specific conditions.

Abstract: An imaging lens includes a first lens group; a second lens group; and a third lens group, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens and a seventh lens having negative refractive power. The fourth lens has a concave surface facing the object side near an optical axis thereof. The seventh lens has an image plane-side surface formed in an aspheric shape having at least one inflexion point. The fifth lens is disposed away from the sixth lens by a specific distance on an optical axis thereof. The first to third lenses have specific Abbe's numbers.

Abstract: An image pickup lens includes an aperture stop, a first lens with positive refractive power having a convex object-side surface, a second meniscus lens having a concave image-side surface, a third meniscus lens having a convex image-side surface, a fourth meniscus lens having a concave object-side surface near an optical axis, and a fifth meniscus lens having a concave image-side surface near the optical axis, wherein the image-side surface of the fourth lens has an aspherical shape in which a positive refractive power weakens toward the periphery, and wherein the following conditional expressions (1) and (7) are satisfied: 0.55<f1/f<1.0??(1) ?1.6<f2/f<?0.7??(7) where f represents a focal length of an overall image pickup lens, f1 represents a first lens focal length, and f2 represents a second lens focal length.

Abstract: To provide a compact and bright imaging lens achieving higher optical performance than conventional arts, having a wide field of view of about 80 degrees or more and enabling proper correction of aberrations even if application is made to a large imaging sensor. An imaging lens for a solid-state imaging sensor comprises, in order from an object side to an image side, a first lens having positive or negative refractive power, a second lens having positive refractive power, a third lens having negative refractive power, a fourth lens having positive or negative refractive power and an aspheric surface on the both sides, a fifth lens having positive refractive power, and a sixth lens having negative refractive power and an aspheric surface on the both sides, wherein a conditional expression (1) below is satisfied: (1) 0.84<|r1/f| where f: focal length of an overall optical system of the imaging lens, and r1: curvature radius of an object-side surface of the first lens.

Abstract: An imaging lens includes a first lens group having positive refractive power; a second lens group having negative refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having positive refractive power. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens having positive refractive power and a seventh lens having negative refractive power. The first to third lenses and the sixth to seventh lenses have specific Abbe's numbers.

Abstract: An imaging lens includes a first lens; a second lens; a third lens; a fourth lens; and a fifth lens, arranged from an object side to an image plane side. The first lens is formed in a shape so that a curvature radius of a surface on the object side is positive. The third lens is formed such that a curvature radius of a surface on the object side is positive. The fourth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric. The fifth lens is formed such that a surface on the object side and a surface on the image plane side are aspheric, and a curvature radius of the surface on the image plane side is positive near an optical axis thereof. The fourth lens and the fifth lens have specific Abbe's numbers.