Optical imaging lens and electronic device including the lens
An imaging optical lens includes, in order from object side to image side, an aperture stop, first, second, third, fourth, and fifth lens elements, each of the five lens elements having an object side surface and an image side surface. The object side surface of the first lens element is convex along an optical axis. The image-side surface of the second lens element concave in the vicinity of an outer circumference. The object side of the fourth lens element is convex in the vicinity of the outer circumference. The image side surface of the fifth lens element is concave in the vicinity of the optical axis and convex in the vicinity of the outer circumference. The first, second, third, fourth, and fifth lens elements have a refractive power. The thicknesses of the first, second, third, fourth, and fifth lens elements and the air gaps between them satisfy specific conditions.
1. An optical imaging lens having only five lens elements, the optical imaging lens comprising, in order from an object side to an image side, an aperture stop, first, second, third, fourth, and fifth lens elements, each of the five lens elements having an object side surface and an image side surface, wherein:
the object side surface of the first lens element is convex in the vicinity of an optical axis;
the image side surface of the second lens element is concave in the vicinity of an outer circumference;
the image side surface of the third lens element is convex in the vicinity of its outer circumference;
the object side surface of the fourth lens element is convex in the vicinity of the outer circumference;
the image side surface of the fifth lens element is concave in the vicinity of the optical axis and convex in the vicinity of the outer circumference, and the object side surface of the fifth lens has a convex portion in the vicinity of the optical axis; and
the first, second, third, fourth, and fifth lens elements have a refractive power;
wherein the optical imaging lens does not include any lens element with refractive power other than said first, second, third, fourth and fifth lens elements, and
wherein an air gap between the first and second lens elements along the optical axis is AG 12 , an air gap between the second and third lens elements along the optical axis is AG 23 , an air gap between the third and fourth lens elements along the optical axis is AG 34 , an air gap between the fourth and fifth lens elements along the optical axis is AG 45 , and they satisfy the relation:
1.20≦( AG 34+ AG 45)/( AG 12+ AG 23).
2. The optical imaging lens of claim 1 , wherein the the image side surface of the first lens element is convex in the vicinity of the outer circumference.
3. The optical imaging lens of claim 2 , wherein a sum of total air gaps between the first, second, third, fourth, and fifth lens elements along the optical axis is AAG, and they satisfy the relation:
AAG/AG 34≦16.00.
4. The optical imaging lens of claim 3 , wherein a thickness of the second lens element along the optical axis is T 2 , and it satisfies the relation:
0.65≦ AG 34/ T 2.
5. The optical imaging lens of claim 4 , further satisfying the relation:
1.50≦( AG 34+ AG 45)/ T 2.
6. The optical imaging lens of claim 5 , wherein a thickness of the fourth lens element along the optical axis is T 4 , a thickness of the fifth lens element along the optical axis is T 5 , and they satisfy the relation:
4.00≦( T 4+ T 5)/ T 2.
7. The optical imaging lens of claim 6 , wherein the thicknesses T 2 and T 5 of the respective second and fifth lens elements satisfy the relation:
1.80≦ T 5/ T 2.
8. The optical imaging lens of claim 5 , wherein the object side surface of the fifth lens element is convex in the vicinity of the outer circumference.
9. The optical imaging lens of claim 3 , wherein a thickness of the second lens element along the optical axis is T 2 , and it satisfies the relation:
1.50≦( AG 34+ AG 45)/ T 2.
10. The optical imaging lens of claim 9 , wherein a thickness of the fifth lens element along the optical axis is T 5 , and it satisfies the relation:
2.60≦( AG 45+ T 5)/ T 2.
11. The optical imaging lens of claim 10 , wherein a thickness of the fourth lens element along the optical axis is T 4 , and it satisfies the relation
4.90≦( T 4+ T 5)/ T 2.
12. The optical imaging lens of claim 2 , wherein a thickness of the second lens element along the optical axis is T 2 , and it satisfies the relation:
0.65≦ AG 34/ T 2.
13. The optical imaging lens of claim 12 , further satisfying the relation:
1.00≦ AG 45/ T 2.
14. The optical imaging lens of claim 13 , wherein an effective focal length is EFL, a thickness of the fifth lens element is T 5 , and they satisfy the relation:
EFL /( AG 45+ T 5)≦5.20.
15. The optical imaging lens of claim 14 , wherein a total length from the object-side surface of the first lens element to an image side surface of the fifth element along the optical axis is TL, and they satisfy the relation:
10.0≦( TL+T 5)/ AG 45<22.0.
16. The optical imaging lens of claim 2 , wherein a thickness of the second lens element along the optical axis is T 2 , and it satisfies the relation:
1.50≦( AG 34+ AG 45)/ T 2.
17. The optical imaging lens of claim 16 , wherein a thickness of the fifth lens element along the optical axis is T 5 , an effective focal length is EFL, and they satisfy the relation:
EFL /( AG 34+ T 5)≦6.8.
18. An electronic device with a digital camera, the electronic device comprising:
a case;
a module housing unit disposed within the case;
a lens barrel mounted in the module housing unit; and
an optical lens module assembled in the lens barrel, the optical lens module having only five lens elements comprising, in order from an object side to an image side, an aperture stop, first, second, third, fourth, and fifth lens elements, each of the five lens elements having an object side surface and an image side surface, wherein:
the object side surface of the first lens element is convex in the vicinity of an optical axis;
the image side surface of the second lens element is concave in the vicinity of an outer circumference;
the image side surface of the third lens element is convex in the vicinity of the outer circumference;
the object side surface of the fourth lens element is convex in the vicinity of the outer circumference;
the image side surface of the fifth lens element is concave in the vicinity of the optical axis and convex in the vicinity of the outer circumference, and the object side surface of the fifth lens has a convex portion in the vicinity of the optical axis; and
the first, second, third, fourth, and fifth lens elements have a refractive power;
wherein the optical lens module does not include any lens element with refractive power other than said first, second, third, fourth and fifth lens elements, and
wherein an air gap between the first and second lens elements along the optical axis is AG 12 , an air gap between the second and third lens elements along the optical axis is AG 23 , an air gap between the third and fourth lens elements along the optical axis is AG 34 , an air gap between the fourth and fifth lens elements along the optical axis is AG 45 , and they satisfy the relation:
1.20≦( AG 34+ AG 45)/( AG 12+ AG 23).
19. The electronic device of claim 18 , wherein the lens barrel is movable lengthwise in a direction of the optical axis.