Optical photographing lens assembly, imaging apparatus and electronic device
An optical photographing lens assembly includes seven lens elements, which are, 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. The first lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof. The third lens element has positive refractive power. The seventh lens element has an image-side surface being concave in a paraxial region thereof and including at least one convex shape in an off-axis region thereof. An object-side surface and the image-side surface of the seventh lens element are aspheric.
1. An optical photographing lens assembly 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 the first lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof; the third lens element has positive refractive power; the seventh lens element has an image-side surface being concave in a paraxial region thereof and comprising at least one convex shape in an off-axis region thereof, and an object-side surface and the image-side surface of the seventh lens element are aspheric;
wherein a focal length of the first lens element is f1, a focal length of the second lens element is f2, a focal length of the third lens element is f3, a focal length of the fourth lens element is f4, a focal length of the fifth lens element is f5, a focal length of the sixth lens element is f6, a focal length of the seventh lens element is f7, a focal length of the optical photographing lens assembly is f, a curvature radius of the object-side surface of the seventh lens element is R13, an axial distance between the third lens element and the fourth lens element is T34, an axial distance between the fourth lens element and the fifth lens element is T45, and the following conditions are satisfied:
| f 3/ f 1|≤0.84;
| f 3/ f 2|≤1.0;
| f 3/ f 4|≤1.0;
| f 3/ f 5|≤1.0;
| f 3/ f 6|≤1.0;
| f 3/ f 7|≤1.0;
0.20≤ f/R 13; and
T 34/ T 45≤8.0.
2. The optical photographing lens assembly of claim 1 , wherein the sixth lens element has an object-side surface being convex in a paraxial region thereof and comprising at least one concave shape in an off-axis region thereof, and the sixth lens element has an image-side surface being concave in a paraxial region thereof and comprising at least one convex shape in an off-axis region thereof.
3. The optical photographing lens assembly of claim 1 , wherein a maximum of refractive indexes of all the lens elements of the optical photographing lens assembly is Nmax, and the following condition is satisfied:
1.650≤ N max<1.75.
4. The optical photographing lens assembly of claim 1 , wherein the optical photographing lens assembly comprises two adjacent lens elements having Abbe numbers less than 30.
5. The optical photographing lens assembly of claim 1 , wherein the focal length of the optical photographing lens assembly is f, the curvature radius of the object-side surface of the seventh lens element is R13, and the following condition is satisfied:
0.70< f/R 13<5.0.
6. The optical photographing lens assembly of claim 1 , wherein the first lens element has an image-side surface being concave in a paraxial region thereof.
7. The optical photographing lens assembly of claim 1 , wherein the focal length of the optical photographing lens assembly is f, the focal length of the third lens element is f3, and the following condition is satisfied:
f/f 3<1.0.
8. The optical photographing lens assembly of claim 1 , wherein the focal length of the first lens element is f1, the focal length of the second lens element is f2, the focal length of the fourth lens element is f4, the focal length of the fifth lens element is f5, the focal length of the sixth lens element is f6, the focal length of the seventh lens element is f7, and the following conditions are satisfied:
| f 7/ f 1|≤1.0;
| f 7/ f 2|≤1.0;
| f 7/ f 4|≤1.0;
| f 7/ f 5|≤1.0; and
| f 7/ f 6|≤1.0.
9. The optical photographing lens assembly of claim 1 , wherein an axial distance between the object-side surface of the first lens element and an image surface is TL, a maximum image height of the optical photographing lens assembly is ImgH, an f-number of the optical photographing lens assembly is Fno, a maximum field of view of the optical photographing lens assembly is FOV, and the following conditions are satisfied:
0.80< TL/ImgH< 1.60;
1.0< Fno< 2.0; and
70 degrees< FOV< 100 degrees.
10. The optical photographing lens assembly of claim 1 , wherein the axial distance between the third lens element and the fourth lens element is T34, the axial distance between the fourth lens element and the fifth lens element is T45, and the following condition is satisfied:
0.50< T 34/ T 45<6.0.
11. The optical photographing lens assembly of claim 1 , wherein a displacement in parallel with an optical axis from an axial vertex on the image-side surface of the seventh lens element to a maximum effective radius position on the image-side surface of the seventh lens element is Sag72, a central thickness of the seventh lens element is CT7, and the following condition is satisfied:
1.0<| Sag 72|/ CT 7.
12. The optical photographing lens assembly of claim 1 , wherein the object-side surface of the seventh lens element comprises at least two critical points.
13. The optical photographing lens assembly of claim 1 , wherein the fourth lens element has an image-side surface being concave in a paraxial region thereof and comprising at least one convex shape in an off-axis region thereof.
14. The optical photographing lens assembly of claim 1 , wherein the focal length of the first lens element is f1, the focal length of the third lens element is f3, the focal length of the sixth lens element is f6, and the following conditions are satisfied:
| f 3/ f 1|<0.75; and
| f 3/ f 6|<0.60.
15. The optical photographing lens assembly of claim 1 , wherein a total number of lens elements having Abbe numbers less than 30 is V30, and the following condition is satisfied:
3≤ V 30.
16. The optical photographing lens assembly of claim 1 , wherein the sixth lens element has positive refractive power.
17. The optical photographing lens assembly of claim 1 , wherein a vertical distance between a non-axial critical point on an object-side surface of the sixth lens element and an optical axis is Yc61, a vertical distance between a non-axial critical point on an image-side surface of the sixth lens element and the optical axis is Yc62, and the following condition is satisfied:
0.3< Yc 61/ Yc 62<1.5.
18. The optical photographing lens assembly of claim 1 , wherein the fourth lens element has negative refractive power.
19. The optical photographing lens assembly of claim 1 , wherein a total number of lens elements having Abbe numbers less than 20 is V20, and the following condition is satisfied:
1≤ V 20.
20. The optical photographing lens assembly of claim 1 , wherein a curvature radius of an object-side surface of the fourth lens element is R7, a curvature radius of an image-side surface of the fourth lens element is R8, and the following condition is satisfied:
0≤ R 8/| R 7|<1.0.
21. The optical photographing lens assembly of claim 1 , wherein a central thickness of the first lens element is CT1, a central thickness of the third lens element is CT3, and the following condition is satisfied:
1.0< CT 3/ CT 1<3.0.
22. The optical photographing lens assembly of claim 1 , wherein the focal length of the optical photographing lens assembly is f, a curvature radius of an object-side surface of the fifth lens element is R9, a curvature radius of an image-side surface of the fifth lens element is R10, and the following condition is satisfied:
| f/R 9|+| f/R 10|<3.50.
23. The optical photographing lens assembly of claim 1 , wherein the focal length of the optical photographing lens assembly is f, a curvature radius of an object-side surface of the sixth lens element is R11, a curvature radius of an image-side surface of the sixth lens element is R12, and the following condition is satisfied:
| f/R 11|+| f/R 12|<2.70.
24. The optical photographing lens assembly of claim 1 , wherein 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, an entrance pupil diameter of the optical photographing lens assembly is EPD, and the following condition is satisfied:
0.8< TD/EPD< 2.0.
25. An imaging apparatus, comprising:
the optical photographing lens assembly of claim 1 ; and
an image sensor, wherein the image sensor is disposed on an image surface of the optical photographing lens assembly.
26. An electronic device, comprising:
the imaging apparatus of claim 25 .