Imaging optical lens assembly including five lenses +−++−, −++−, −−++−, +−+++, +++−+, +−+−+, +−+−−, or −++−+ of refractive powers, imaging apparatus and electronic device

An imaging optical lens assembly comprising five lens elements, the five lens elements being, in order from an object side to an image side along an optical path:

• a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element, each of the five lens elements has an object-side surface towards the object side and an image-side surface towards the image side;
• when the first lens element has the image-side surface being convex in a paraxial region thereof;
• the second lens element has the image-side surface being concave in a paraxial region thereof;
• the third lens element has positive refractive power;
• the fourth lens element has the object-side surface being concave in a paraxial region thereof and the image-side surface being convex in a paraxial region thereof;
• the fifth lens element has the object-side surface being convex in a paraxial region thereof and the image-side surface being concave in a paraxial region thereof;
• at least one of the object-side surface and the image-side surface of at least one of the five lens elements comprises at least one critical point in an off-axis region thereof;
• wherein a total number of the lens elements in the imaging optical lens assembly is five;
• when an Abbe number of the first lens element is Vd1, an Abbe number of the second lens element is Vd2, an Abbe number of the third lens element is Vd3, an Abbe number of the fourth lens element is Vd4, an Abbe number of the fifth lens element is Vd5, and the following condition is satisfied:
• 55.0<Vd1+Vd2+Vd3+Vd4+Vd5<140.0;
• wherein a focal length of the imaging optical lens assembly is f, a focal length of the third lens element is f3, a curvature radius of the image-side surface of the second lens element is R4, and the following conditions are satisfied:
• 0<f3/f<4.5;
• and
• 0.30<R4/f<0.60;
• wherein a distance between a critical point of the image-side surface of the fifth lens element and an optical axis is Yc52, a maximum distance between an optical effective region of the image-side surface of the fifth lens element and the optical axis is Y52, and the image-side surface of the fifth lens element comprises at least one critical point in an off-axis region thereof satisfying the following condition:
• 0.60<Yc52/Y52<0.90.