Image lens assembly and image capturing device

摘要

An image lens assembly includes five lens elements with refractive power, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element has refractive power. The second lens element with positive refractive power has a convex image-side surface in a paraxial region thereof. The third lens element has positive refractive power. The fourth lens element with refractive power has a concave image-side surface in a paraxial region thereof, wherein the surfaces thereof are aspheric. The fifth lens element with refractive power has a concave image-side surface in a paraxial region thereof, wherein the image-side surface of the fifth lens element has at least one convex shape in an off-axis region thereof, and the surfaces thereof are aspheric.

主权项

1. An image lens assembly comprising, in order from an object side to an image side:
a first lens element having refractive power; a second lens element with positive refractive power having a convex image-side surface in a paraxial region thereof; a third lens element having positive refractive power; a fourth lens element with refractive power having a concave image-side surface in a paraxial region thereof, wherein an object-side surface and the image-side surface of the fourth lens element are aspheric; and a fifth lens element with refractive power having a concave image-side surface in a paraxial region thereof, wherein the image-side surface of the fifth lens element has at least one convex shape in an off-axis region thereof, and an object-side surface and the image-side surface of the fifth lens element are aspheric; wherein the image lens assembly has a total of five lens elements with refractive power, each of the five lens elements of the image lens assembly is separated from each other, an axial distance between an object-side surface of the first lens element and an image plane is TL, a curvature radius of an image-side surface of the first lens element is R2, a curvature radius of an object-side-surface of the second lens element is R3, a curvature radius of the image-side surface of the second lens element is R4, an axial distance between the first lens element and the second lens element is T12, an axial distance between the second lens element and the third lens element is T23, an axial distance between the third lens element and the fourth lens element is T34, an axial distance between the fourth lens element and the fifth lens element is T45, a focal length of the image lens assembly is f, and the following conditions are satisfied:
TL/R2<3.0;−1.0<(R3+R4)/(R3−R4)<0.5; and(T12+T23+T34+T45)/f<0.35.