Image capturing optical system, imaging apparatus and electronic device
An image capturing optical system includes seven lens elements, the seven lens elements being, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. An image-side surface of the fifth lens element is convex in a paraxial region thereof. An image-side surface of the sixth lens element is concave in a paraxial region thereof. The seventh lens element has negative refractive power.
1. An image capturing optical system comprising seven lens elements, the seven lens elements being, in order from an object side to an image side:
a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element; wherein each of the seven lens elements has an object-side surface facing towards the object side and an image-side surface facing towards the image side;
wherein the first lens element has negative refractive power, the object-side surface of the first lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof, the image-side surface of the first lens element is convex in a paraxial region thereof; the object-side surface of the seventh lens element is convex in a paraxial region thereof, the image-side surface of the seventh lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof;
wherein a curvature radius of the object-side surface of the seventh lens element is R13, a curvature radius of the image-side surface of the seventh lens element is R14, and the following condition is satisfied:
−0.70< R 14/ R 13<1.40.
2. The image capturing optical system of claim 1 , wherein the second lens element has positive refractive power; the seventh lens element has negative refractive power.
3. The image capturing optical system of claim 1 , wherein the sixth lens element has positive refractive power; a vertical distance between a non-axial critical point on the image-side surface of the seventh lens element and an optical axis is Yc72, a focal length of the image capturing optical system is f, and the following condition is satisfied:
0.10< Yc 72/ f< 0.85.
4. The image capturing optical system of claim 1 , wherein the object-side surface of the fifth lens element is concave in a paraxial region thereof, the image-side surface of the fifth lens element is convex in a paraxial region thereof.
5. The image capturing optical system of claim 1 , wherein a curvature radius of the object-side surface of the third lens element is R5, a curvature radius of the image-side surface of the third lens element is R6, and the following condition is satisfied:
| R 5/ R 6|<4.50.
6. The image capturing optical system of claim 1 , wherein a curvature radius of the object-side surface of the second lens element is R3, an axial distance between the object-side surface of the first lens element and the image-side surface of the seventh lens element is TD, and the following condition is satisfied:
−0.70< R 3/ TD< 0.80.
7. The image capturing optical system of claim 1 , wherein a focal length of the first lens element is f1, a focal length of the third lens element is f3, and the following condition is satisfied:
−0.80< f 3/ f 1<1.55.
8. The image capturing optical system of claim 1 , wherein the curvature radius of the image-side surface of the seventh lens element is R14, an entrance pupil diameter of the image capturing optical system is EPD, and the following condition is satisfied:
0.10 <R 14/EPD<1.0.
9. An imaging apparatus, comprising:
the image capturing optical system of claim 1 ;
a driving apparatus connected to the image capturing optical system; and
an image sensor disposed on an image surface of the image capturing optical system.
10. An electronic device, comprising:
the imaging apparatus of claim 9 .
11. An image capturing optical system comprising seven lens elements, the seven lens elements being, in order from an object side to an image side:
a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element; wherein each of the seven lens elements has an object-side surface facing towards the object side and an image-side surface facing towards the image side;
wherein the object-side surface of the first lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof, the image-side surface of the first lens element is convex in a paraxial region thereof; the second lens element has positive refractive power, the object-side surface of the second lens element is convex in a paraxial region thereof, the image-side surface of the second lens element is concave in a paraxial region thereof; the image-side surface of the fifth lens element is convex in a paraxial region thereof; the object-side surface of the seventh lens element is convex in a paraxial region thereof, the image-side surface of the seventh lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof;
wherein a curvature radius of the object-side surface of the seventh lens element is R13, a curvature radius of the image-side surface of the seventh lens element is R14, and the following condition is satisfied:
−0.70< R 14/ R 13<1.40.
12. The image capturing optical system of claim 11 , wherein the object-side surface of the sixth lens element is convex in a paraxial region thereof, the image-side surface of the sixth lens element is concave in a paraxial region thereof.
13. The image capturing optical system of claim 11 , wherein a focal length of the first lens element is f1, a focal length of the third lens element is f3, and the following condition is satisfied:
−0.80< f 3/ f 1<1.55.
14. The image capturing optical system of claim 11 , wherein an axial distance between the object-side surface of the first lens element and an image surface is TL, and the following condition is satisfied:
TL<7.5 mm.
15. The image capturing optical system of claim 11 , wherein a vertical distance between a non-axial critical point on the image-side surface of the sixth lens element and an optical axis is Yc62, a vertical distance between a non-axial critical point on the image-side surface of the seventh lens element and the optical axis is Yc72, and the following condition is satisfied:
0.50< Yc 72/ Yc 62<1.85.
16. An image capturing optical system comprising seven lens elements, the seven lens elements being, in order from an object side to an image side:
a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element; wherein each of the seven lens elements has an object-side surface facing towards the object side and an image-side surface facing towards the image side;
wherein the first lens element has negative refractive power, the object-side surface of the first lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof; the fifth lens element has negative refractive power; the object-side surface of the seventh lens element is convex in a paraxial region thereof, the image-side surface of the seventh lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off axis region thereof;
wherein a curvature radius of the object-side surface of the seventh lens element is R13, a curvature radius of the image-side surface of the seventh lens element is R14, a focal length of the first lens element is f1, a focal length of the third lens element is f3, and the following conditions are satisfied:
−0.70< R 14/ R 13<1.40; and
−1.50< f 3/ f 1<1.55.
17. The image capturing optical system of claim 16 , wherein the sixth lens element has positive refractive power; the seventh lens element has negative refractive power.
18. The image capturing optical system of claim 16 , wherein the object-side surface of the third lens element is convex in a paraxial region thereof.
19. The image capturing optical system of claim 16 , wherein the image-side surface of the fourth lens element is convex in a paraxial region thereof.
20. The image capturing optical system of claim 16 , wherein a curvature radius of the object-side surface of the third lens element is R5, a curvature radius of the image-side surface of the third lens element is R6, and the following condition is satisfied:
| R 5/ R 6|<4.50.
21. The image capturing optical system of claim 16 , wherein a curvature radius of the object-side surface of the second lens element is R3, an axial distance between the object-side surface of the first lens element and the image-side surface of the seventh lens element is TD, and the following condition is satisfied:
−0.70 <R 3/ TD< 0.80.
22. An image capturing optical system comprising seven lens elements, the seven lens elements being, in order from an object side to an image side:
a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element; wherein each of the seven lens elements has an object-side surface facing towards the object side and an image-side surface facing towards the image side;
wherein the object-side surface of the first lens element is concave in a paraxial region thereof and comprises at least one convex in an off-axis region thereof; the image-side surface of the second lens element is concave in a paraxial region thereof; the fifth lens element has negative refractive power, the object-side surface of the fifth lens element is concave in a paraxial region thereof, the image-side surface of the fifth lens element is convex in a paraxial region thereof; the object-side surface of the seventh lens element is convex in a paraxial region thereof, the image-side surface of the seventh lens element is concave in a paraxial region thereof and comprises at least one convex surface in an off-axis region thereof;
wherein a curvature radius of the object-side surface of the seventh lens element is R13, a curvature radius of the image-side surface of the seventh lens element is R14, and the following condition is satisfied:
−0.70< R 14/ R 13<1.40.
23. The image capturing optical system of claim 22 , wherein the second lens element has positive refractive power; the fourth lens element has positive refractive power.
24. The image capturing optical system of claim 22 , wherein the object-side surface of the sixth lens element is convex in a paraxial region thereof.
25. The image capturing optical system of claim 22 , wherein each of at least two of the seven lens elements has an Abbe number smaller than 25.0.
26. The image capturing optical system of claim 22 , wherein a focal length of the image capturing optical system is f, a focal length of the second lens element is f2, and the following condition is satisfied:
0.40<| f/f 2|<1.20.
27. The image capturing optical system of claim 22 , wherein an axial distance between the object-side surface of the first lens element and an image surface is TL, and the following condition is satisfied:
TL<7.5 mm.