Image pickup optical lens assembly
An image pick-up optical lens assembly, sequentially arranged from an object side to an image side along an optical axis, comprises: a first lens element with a positive refractive power having a convex object-side surface, a second lens element with a negative refractive power, a third lens element with a positive refractive power, a meniscus fourth lens element with a positive refractive power having at least one aspherical optical surface, and a fifth lens element with a positive refractive power having at least one inflection point on the optical image-side surface. Additionally, the image pick-up optical lens assembly satisfies several particular conditions. The invention possesses features such as good aberration compensation, well-performed modulation transfer function and short total length of lens assembly applicable for compact cameras and mobile phones.
1. An image pick-up optical lens assembly, sequentially arranged from an object side to an image side along an optical axis, comprising:
a first lens element with a positive refractive power, having a convex object-side surface;
a second lens element with a negative refractive power;
a third lens element with a positive refractive power;
a fourth lens element with a positive refractive power, being a meniscus lens element, and at least one of the object-side and image-side surfaces being aspheric;
a fifth lens element with a positive refractive power, having a convex object-side surface and a concave image-side surface, and at least one of the object-side and image-side surfaces being aspheric, and the image-side surface of the fifth lens element having at least one inflection point;
wherein, f is the focal length of the image pick-up optical lens assembly, f 1 is the focal length of the first lens element, CT 1 is the thickness of the first lens element on the optical axis, CT 2 is the thickness of the second lens element on the optical axis, and the relation of 0.7<f/f 1 <2.0 and 0.8<CT 1 /CT 2 <2.80 are satisfied, wherein R 3 is the radius of curvature of the object-side surface of the second lens element, R 4 is the radius of curvature of the image-side surface of the second lens element, and the relation of −0.5<R 4 /R 3 <0.5 is satisfied.
2. The image pick-up optical lens assembly of claim 1 , wherein the second lens element has a concave image-side surface, and the fifth lens element is made of plastic material.
3. The image pick-up optical lens assembly of claim 2 , wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, f 4 is the focal length of the fourth lens element, f 5 is the focal length of the fifth lens element, and the relation of |f/f 3 |+|f/f 4 |+|f/f 5 |<0.90 is satisfied.
4. The image pick-up optical lens assembly of claim 3 , wherein f is the focal length of the image pick-up optical lens assembly, T d is the distance from the object-side surface of the first lens element to the image-side surface of the fifth lens element on the optical axis, and the relation of 0.65<T d /f<0.95 is satisfied.
5. The image pick-up optical lens assembly of claim 3 , wherein the second lens element has a concave object-side surface.
6. The image pick-up optical lens assembly of claim 3 , wherein f 2 is the focal length of the second lens element, f 5 is the focal length of the fifth lens element, and the relation of −13.5<f 5 /f 2 <−4.0 is satisfied.
7. The image pick-up optical lens assembly of claim 3 , wherein R 9 is the radius of curvature of the object-side surface of the fifth lens element, R 10 is the radius of curvature of the image-side surface of the fifth lens element, and the relation of 0.01<(R 9 −R 10 )/(R 9 +R 10 )<0.07 is satisfied.
8. The image pick-up optical lens assembly of claim 2 , wherein v 1 is the Abbe number of the first lens element, v 2 is the Abbe number of the second lens element, and the relation of 28<v 1 −v 2 <40 is satisfied.
9. The image pick-up optical lens assembly of claim 2 , wherein the first lens element is made of glass material.
10. The image pick-up optical lens assembly of claim 2 , wherein the fourth lens element has a concave object-side surface and a convex image-side surface.
11. The image pick-up optical lens assembly of claim 2 , wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, and the relation of 0<f/f 3 <0.24 is satisfied.
12. The image pick-up optical lens assembly of claim 1 , wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, f 4 is the focal length of the fourth lens element, f 5 is the focal length of the fifth lens element, and the relation of |f/f 3 |+|f/f 4 |+|f/f 5 |<0.65 is satisfied.
13. The image pick-up optical lens assembly of claim 1 , wherein f is the focal length of the image pick-up optical lens assembly, CT 2 is the thickness of the second lens element on the optical axis, CT 3 is the thickness of the third lens element on the optical axis, and the relation of 0.07<(CT 2 +CT 3 )/f<0.18 is satisfied.
14. An image pick-up optical lens assembly, sequentially arranged from an object side to an image side along an optical axis, comprising:
a first lens element with a positive refractive power, having a convex object-side surface;
a second lens element with a negative refractive power;
a third lens element with a positive refractive power;
a fourth lens element with a positive refractive power, being a meniscus lens element, and at least one of the object-side and image-side surfaces being aspheric;
a fifth lens element with a positive refractive power, having a convex object-side surface and a concave image-side surface, and at least one of the object-side and image-side surfaces being aspheric and the image-side surface of the fifth lens element having at least one inflection point;
wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, f 4 is the focal length of the fourth lens element, f 5 is the focal length of the fifth lens element, R 3 is the radius of curvature of the object-side surface of the second lens element, R 4 is the radius of curvature of the image-side surface of the second lens element, and the relations of |f/f 3 |+|f/f 4 |+|f/f 5 |<0.90 and −0.9<R 4 /R 3 <0.9 are satisfied.
15. The image pick-up optical lens assembly of claim 14 , wherein the second lens element has a concave image-side surface, and the fifth lens element is made of plastic material.
16. The image pick-up optical lens assembly of claim 15 , wherein the fourth lens element has a concave object-side surface and a convex image-side surface.
17. The image pick-up optical lens assembly of claim 16 , wherein v 1 is the Abbe number of the first lens element, v 2 is the Abbe number of the second lens element, and the relation of 28<v 1 -v 2 <40 is satisfied.
18. The image pick-up optical lens assembly of claim 17 , wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, f 4 is the focal length of the fourth lens element, f 5 is the focal length of the fifth lens element, and the relation of |f/f 3 |+|f/f 4 |+|f/f 5 |<0.65 is satisfied.
19. The image pick-up optical lens assembly of claim 17 , wherein R 3 is the radius of curvature of the object-side surface of the second lens element, R 4 is the radius of curvature of the image-side surface of the second lens element, and the relation of −0.5<R 4 /R 3 <0.5 is satisfied.
20. The image pick-up optical lens assembly of claim 17 , wherein f 2 is the focal length of the second lens element, f 5 is the focal length of the fifth lens element, and the relation of −13.5<f 5 /f 2 <−4.0 is satisfied.
21. The image pick-up optical lens assembly of claim 17 , wherein R 9 is the radius of curvature of the object-side surface of the fifth lens element, R 10 is the radius of curvature of the image-side surface of the fifth lens element, and the relation of 0.01<(R 9 −R 10 )/(R 9 +R 10 )<0.07 is satisfied.
22. The image pick-up optical lens assembly of claim 17 , wherein f is the focal length of the image pick-up optical lens assembly, CT 2 is the thickness of the second lens element on the optical axis, CT 3 is the thickness of the third lens element on the optical axis, and the relation of 0.07<(CT 2 +CT 3 )/f<0.18 is satisfied.
23. The image pick-up optical lens assembly of claim 16 , wherein the first lens element is made of glass material.
24. The image pick-up optical lens assembly of claim 16 , wherein f is the focal length of the image pick-up optical lens assembly, f 3 is the focal length of the third lens element, and the relation of 0<f/f 3 <0.24 is satisfied.