Imaging lens

An imaging lens comprising, in sequence from an object side to an image plane side:

• an aperture stop with a predetermined diameter;
• a first lens with an overall positive refractive power having a convex surface facing toward the object side and having a meniscus shape with said convex surface facing toward the object side and a concave surface facing toward the image plane side;
• a second lens with an overall positive refractive power having a concave surface facing toward the object side;
• and
• a third lens with an overall negative refractive power having a concave surface facing toward the object side;
• wherein said second lens is formed with aspherical surfaces on said object side surface and an image plane side surface;
• and
• wherein said third lens is formed with aspherical surfaces on said object side surface and an image plane side surface and is formed with an inflection point, where a curvature orientation changes, within an effective diameter range of said aspherical surface on said image plane side surface.

An imaging lens comprising, in sequence from an object side to an image plane side:

• an aperture stop with a predetermined diameter;
• a first lens with an overall positive refractive power having a convex surface facing toward the object side;
• a second lens with an overall positive refractive power having a concave surface facing toward the object side;
• and
• a third lens with an overall negative refractive power having a concave surface facing toward the object side;
• wherein said second lens is formed with aspherical surfaces on said object side surface and an image plane side surface;
• wherein said third lens is formed with aspherical surfaces on said object side surface and an image plane side surface and is formed with an inflection point, where a curvature orientation changes, within an effective diameter range of said aspherical surface on said image plane side surface;
• and wherein:
• v1>45, v2>45, v3<45
• where v1 is the Abbe number of said first lens, v2 is the Abbe number of said second lens, and v3 is the Abbe number of said third lens.

An imaging lens comprising, in sequence from an object side to an image plane side:

• an aperture stop with a predetermined diameter;
• a first lens with an overall positive refractive power having a convex surface facing toward the object side;
• a second lens with an overall positive refractive power having a concave surface facing toward the object side;
• and
• a third lens with an overall negative refractive power having a concave surface facing toward the object side;
• wherein said second lens is formed with aspherical surfaces on said object side surface and an image plane side surface;
• wherein said third lens is formed with aspherical surfaces on said object side surface and an image plane side surface and is formed with an inflection point, where a curvature orientation changes, within an effective diameter range of said aspherical surface on said image plane side surface;
• and wherein:
• 1<|R4|/|R5|<2
• 6<|R6|/|R7|<10
• where R4 is a curvature radius of said object-side surface of said second lens, R5 is a curvature radius of said image-plane side surface of said second lens, R6 is a curvature radius of said object-side surface of said third lens, and R7 is a curvature radius of said image-plane side surface of said third lens.

An imaging lens comprising, in sequence from an object side to an image plane side:

• an aperture stop with a predetermined diameter;
• a first lens with an overall positive refractive power having a convex surface facing toward the object side;
• a second lens with an overall positive refractive power having a concave surface facing toward the object side;
• and
• a third lens with an overall negative refractive power having a concave surface facing toward the object side;
• wherein said second lens is formed with aspherical surfaces on said object side surface and an image plane side surface;
• wherein said third lens is formed with aspherical surfaces on said object side surface and an image plane side surface and is formed with an inflection point, where a curvature orientation changes, within an effective diameter range of said aspherical surface on said image plane side surface;
• and wherein:
• 0.45<D4/D6<1.0
• where D4 is a thickness along an optical axis of said second lens and D6 is a thickness along said optical axis of said third lens.