Imaging lens assembly

An imaging lens assembly comprising five lens elements with refractive power, in order from an object side to an image side:

• a first lens element with positive refractive power having a convex object-side surface;
• a second lens element having positive refractive power;
• a third lens element having refractive power;
• a fourth lens element with refractive power having a concave image-side surface, wherein both of 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, wherein at least one inflection point is formed on the image-side surface of the fifth lens element, and both of an object-side surface and the image-side surface of the fifth lens element are aspheric;
• wherein a focal length of the first lens element is f1, a focal length of the second lens element is f2, a curvature radius of the object-side surface of the first lens element is R1, a curvature radius of an image-side surface of the first lens element is R2, and the following relationships are satisfied:
• 0<f1/f2<1;
• and
• |R1/R2|<1.