Photographing optical lens assembly
An photographing optical lens assembly includes, in order from an object side to an image side, a first lens element with positive refractive power, a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface, a plastic third lens element with positive refractive power having a concave aspheric object-side surface and a convex aspheric image-side surface, a plastic fourth lens element with negative refractive power having a concave aspheric object-side surface and a convex aspheric image-side surface and a plastic fifth lens element having an aspheric object-side surface and an aspheric image-side surface. By adjusting the focal lengths of the second and the fourth lens element and the photographing optical lens assembly, and the curvature radii of the object-side and the image-side surface of the second lens element, the photographing optical lens assembly is miniaturized, and the image quality is improved.
1. A photographing optical lens assembly comprising, in order from an object side to an image side:
a first lens element with positive refractive power;
a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface;
a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, the object-side surface and the image-side surface of the third lens element being aspheric, and the third lens element being made of plastic;
a fourth lens element with negative refractive power having a concave object-side surface and a convex image-side surface, the object-side surface and the image-side surface of the fourth lens element being aspheric, and the fourth lens element being made of plastic; and
a fifth lens element, the object-side surface and the image-side surface of the fifth lens element being aspheric, and the fifth lens element being made of plastic;
an air distance existing between the first lens element and the second lens element, the photographing optical lens assembly satisfying the following condition:
−1.4 <f/f 2 <−0.3
−1.5 <f/f 4 <−0.2
−0.6<( R 3 +R 4 )/( R 3 −R 4 )<1.0
wherein f is the focal length of the photographing optical lens assembly; f 2 is the focal length of the second lens element; f 4 is the focal length of the fourth lens element; R 3 is the curvature radius of the object-side surface of the second lens element; R 4 is the curvature radius of the image-side surface of the second lens element.
2. The photographing optical lens assembly according to claim 1 , wherein the object-side surface of the first lens element is convex and the image-side surface of the fifth lens element is concave.
3. The photographing optical lens assembly according to claim 2 , wherein the fifth lens element has an inflection point.
4. The photographing optical lens assembly according to claim 3 , wherein the photographing optical lens assembly satisfies the following condition:
1.2 <f/f 1 <2.0
wherein f 1 is the focal length of the first lens element.
5. The photographing optical lens assembly according to claim 3 , wherein the photographing optical lens assembly satisfies the following condition:
20 <V 1 −V 2 <45
wherein, V 1 is the Abbe number of the first lens element, and V 2 is the Abbe number of the second lens element.
6. The photographing optical lens assembly according to claim 5 , wherein the photographing optical lens assembly satisfies the following condition:
30 <V 1 −V 2 <42.
7. The photographing optical lens assembly according to claim 3 , wherein the photographing optical lens assembly satisfies the following condition:
−0.6 <f/f 4 <−0.2
8. The photographing optical lens assembly according to claim 3 , wherein the photographing optical lens assembly satisfies the following condition:
0 <T 12 /T 23 <0.5
wherein T 12 is the axial distance between the first lens element and the second lens element; T 23 is the axial distance between the second lens element and the third lens element.
9. The photographing optical lens assembly according to claim 3 , wherein the photographing optical lens assembly satisfies the following condition:
0<( R 3 +R 4 )/( R 3 −R 4 )<1.0.
10. The photographing optical lens assembly according to claim 9 , wherein the photographing optical lens assembly satisfies the following condition:
−0.5 <f/f 3 +f/f 4 +f/f 5 <0.3
wherein f 3 is the focal length of the third lens element; f 5 is the focal length of the fifth lens element.
11. The photographing optical lens assembly according to claim 9 , wherein the photographing optical lens assembly satisfies the following condition:
−7.5<( R 7 +R 8 )/( R 7 −R 8 )<−3.0
wherein R 7 is the curvature radius of the object-side surface of the fourth lens element, and R 8 is the curvature radius of the image-side surface of the fourth lens element.
12. The photographing optical lens assembly according to claim 3 , further comprising an image sensor disposed on an image plane, and the photographing optical lens assembly satisfying the following condition:
TTL/ImgH< 2.1
wherein TTL is the axial distance between the object-side surface of the first lens element and the image plane; ImgH is a half of the diagonal length of the effective photosensitive area of the image sensor.
13. A photographing optical lens assembly comprising, in order from an object side to an image side:
a first lens element with positive refractive power;
a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface;
a third lens element having a concave object-side surface and a convex image-side surface, the object-side surface and the image-side surface of the third lens element being aspheric, and the third lens element being made of plastic;
a fourth lens element with negative refractive power having a concave object-side surface and a convex image-side surface, the object-side surface and the image-side surface of the fourth lens element being aspheric, and the fourth lens element being made of plastic; and
a fifth lens element, the object-side surface and the image-side surface of the fifth lens element being aspheric, and the fifth lens element being made of plastic;
an air distance existing between the first lens element and the second lens element, the photographing optical lens assembly satisfying the following condition:
−1.5 <f/f 4 <−0.2
−14.0<( R 7 +R 8 )/( R 7 −R 8 )<−2.0
0< T 12 /T 23 <1.4
20 <V 1 −V 2 <45
wherein f is the focal length of the photographing optical lens assembly; f 4 is the focal length of the fourth lens element; R 7 is the curvature radius of the object-side surface of the fourth lens element; R 8 is the curvature radius of the image-side surface of the fourth lens element; T 12 is the axial distance between the first lens element and the second lens element; T 23 is the axial distance between the second lens element and the third lens element; V 1 is the Abbe number of the first lens element, and V 2 is the Abbe number of the second lens element.
14. The photographing optical lens assembly according to claim 13 , wherein the object-side surface of the first lens element is convex, the image-side surface of the fifth lens element is concave, and the fifth lens element has an inflection point.
15. The photographing optical lens assembly according to claim 14 , wherein the photographing optical lens assembly satisfying the following condition:
1.2< f/f 1 <2.0
wherein f 1 is the focal length of the first lens element.
16. The photographing optical lens assembly according to claim 14 , wherein the photographing optical lens assembly satisfying the following condition:
−0.6 <f/f 4 <−0.2.
17. The photographing optical lens assembly according to claim 15 , wherein the photographing optical lens assembly satisfies the following condition:
0<( R 3 +R 4 )/( R 3 −R 4 )<1.0
wherein R 3 is the curvature radius of the object-side surface of the second lens element; R 4 is the curvature radius of the image-side surface of the second lens element.
18. The photographing optical lens assembly according to claim 15 , wherein the photographing optical lens assembly satisfies the following conditions:
0 <T 12 /T 23 <0.5.
19. The photographing optical lens assembly according to claim 15 , wherein the photographing optical lens assembly satisfies the following conditions:
−0.5 <f/f 3 +f/f 4 +f/f 5 <0.3
wherein f 3 is the focal length of the third lens element; f 5 is the focal length of the fifth lens element.