Image capturing lens and image capturing apparatus provided with the image capturing lens
View Patent ↗An image capturing lens which substantially consists of five lenses, composed of a first lens having a positive refractive power with the object side surface being formed in a convex shape toward the object side, a second lens having a negative refractive power, a third lens having a positive refractive power, a fourth lens having a negative refractive power with the object side surface being formed in a concave shape toward the object side, and a fifth lens having a negative refractive power with a region in which the negative refractive power is gradually reduced outwardly in a radial direction from the optical axis, arranged in this order from the object side, and satisfies predetermined conditional expressions.
1. An image capturing lens substantially consisting of five lenses, composed of:
an aperture stop;
a first lens having a positive refractive power with the object side surface being formed in a convex shape toward the object side;
a second lens having a negative refractive power with the object side surface being formed in a convex shape toward the object side;
a third lens;
a fourth lens having the object side surface being formed in a concave shape toward the object side; and
a fifth lens having a negative refractive power with a region in which the negative refractive power is gradually reduced outwardly in a radial direction from the optical axis, arranged in this order from the object side,
wherein the image capturing lens is configured to satisfy a conditional expression given below:
−4.0<f2/f1 (2-3),
3.3<|R3/f2 |<40.0 (8-2),
1.0<TL/f<1.2 (9),
where:
f 2 is a focal length of the second lens;
f 1 is a focal length of the first lens;
R 3 is a paraxial radius of curvature of the object side surface of the second lens;
TL is a length from the object side surface of the first lens to the image forming surface on the optical axis; and
f is a focal length of the entire system.
2. The image capturing lens of claim 1 , wherein the third lens has a positive refractive power.
3. The image capturing lens of claim 1 , wherein the image capturing lens is configured to satisfy a conditional expression given below:
4.2<f3/f1<25.0 (1),
where:
f 1 is a focal length of the first lens; and
f 3 is a focal length of the third lens.
4. The image capturing lens of claim 1 , wherein the fifth lens has a meniscus shape with a convex surface on the object side near the optical axis.
5. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
0.09<D6/f<0.20 (3),
where:
f is a focal length of the entire system; and
D 6 is a distance between the third and fourth lenses on the optical axis.
6. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
2.00<D6/D8 <6.00 (4),
where:
D 6 is a distance between the third and fourth lenses on the optical axis; and
D 8 is a distance between the fourth and fifth lenses on the optical axis.
7. The image capturing lens of claim 1 , wherein the third lens has a convex surface on the object side near the optical axis.
8. The image capturing lens of claim 1 , further satisfying conditional expressions given below:
νd1>50 (5); and
νd2<30 (6),
where:
νd 1 is an Abbe number of the first lens with respect to the d-line; and
νd 2 is an Abbe number of the second lens with respect to the d-line.
9. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
0.09<D2/D1 <0.25 (7),
where:
D 1 a axial thickness of the first lens; and
D 2 is a distance between the first and second lenses on the optical axis.
10. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
−1.9<(R7-R8)/(R7+R8)<0 (10),
where:
R 7 is a paraxial radius of curvature of the object side surfaceof the fourth lens; and
R 8 is a paraxial radius of curvature of the image side surface of the fourth lens.
11. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
4.2<f3/f1<20.0 (1-1),
where:
f 1 is a focal length of the first lens; and
f 3 is a focal length of the third lens.
12. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
0.09<D6/f<0.18 (3-1),
where:
f is a focal length of the entire system; and
D 6 is a distance between the third and fourth lenses on the optical axis.
13. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
2.20<D6/D8<5.60 (4-1),
where:
D 6 is a distance between the third and fourth lenses on the optical axis; and
D 8 is a distance between the fourth and fifth lenses on the optical axis.
14. The image capturing lens of claim 1 , further satisfying conditional expressions given below:
νd1>53 (5-1); and
νd2<25 (6-1),
where:
νd 1 is an Abbe number of the first lens with respect to the d-line; and
νd 2 is an Abbe number of the second lens with respect to the d-line.
15. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
0.09<D2/D1<0.22 (7-1),
where:
D 1 is a axial thickness of the first lens; and
D 2 is a distance between the first and second lenses on the optical axis.
16. The image capturing lens of claim 1 , further satisfying a conditional expression given below:
1.05<TL/f<1.15 (9-1),
where:
TL is a length from the object side surface of the first lens to the image forming surface on the optical axis; and
f is a focal length of the entire system.
17. An image capturing apparatus provided with the image capturing lens of claim 1 .
18. An image capturing lens substantially consisting of five lenses, composed of:
an aperture stop;
a first lens having a positive refractive power with the object side surface being formed in a convex shape toward the object side;
a second lens having a negative refractive power with the object side surface being formed in a convex shape toward the object side;
a third lens;
a fourth lens having the object side surface being formed in a concave shape toward the object side; and
a fifth lens having a negative refractive power, a convex surface on the object side near an optical axis and a region in which the negative refractive power is gradually reduced outwardly in a radial direction from the optical axis, arranged in this order from the object side,
wherein the image capturing lens is configured to satisfy a conditional expression given below:
−4.0<f2/f1 (2-3),
0.09<D2/D1<0.25 (7),
3.3<|R3/f2| (8-3),
1.0<TL/f<1.2 (9),
where:
f 2 is a focal length of the second lens;
f 1 is a focal length of the first lens;
D 1 is an axial thickness of the first lens;
D 2 is a distance between the first and second lenses on the opticalaxis;
R 3 is a paraxial radius of curvature of the object side surface of the second lens;
TL is a length from the object side surface of the first lens to the image forming surface on the optical axis; and
f is a focal length of the entire system.
19. The image capturing lens of claim 18 , wherein the third lens has a positive refractive power.
20. The image capturing lens of claim 18 , wherein the image capturing lens is configured to satisfy a conditional expression given below:
4.2<f3/f1<25.0 (1),
where:
f 1 is a focal length of the first lens; and
f 3 is a focal length of the third lens.
21. The image capturing lens of claim 18 , wherein the fifth lens has a meniscus shape with a convex surface on the object side near the optical axis.
22. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
0.09<D6/f<0.20 (3),
where:
f is a focal length of the entire system; and
D 6 is a distance between the third and fourth lenses on the optical axis.
23. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
2.00<D6/D8<6.00 (4),
where:
D 6 is a distance between the third and fourth lenses on the optical axis; and
D 8 is a distance between the fourth and fifth lenses on the optical axis.
24. The image capturing lens of claim 18 , wherein the third lens has a convex surface on the object side near the optical axis.
25. The image capturing lens of claim 18 , further satisfying conditional expressions given below:
νd1>50 (5); and
νd2<30 (6),
where:
νd 1 is an Abbe number of the first lens with respect to the d-line; and
νd 2 is an Abbe number of the second lens with respect to the d-line.
26. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
−1.9<(R7-R8)/(R7+R8)<0 (10),
where:
R 7 is a paraxial radius of curvature of the object side surface of the fourth lens; and
R 8 is a paraxial radius of curvature of the image side surface of the fourth lens.
27. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
4.2<f3/f1<20.0 (1-1),
where:
fl is a focal length of the first lens; and
f 3 is a focal length of the third lens.
28. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
0.09<D6/f<0.18 (3-1),
where:
f is a focal length of the entire system; and
D 6 is a distance between the third and fourth lenses on the optical axis.
29. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
2.20<D6/D8<5.60 (4-1),
where:
D 6 is a distance between the third and fourth lenses on the optical axis; and
D 8 is a distance between the fourth and fifth lenses on the optical axis.
30. The image capturing lens of claim 18 , further satisfying conditional expressions given below:
νd1>53 (5-1); and
νd2<25 (6-1),
where:
νd 1 is an Abbe number of the first lens with respect to the d-line; and
νd 2 is an Abbe number of the second lens with respect to the d-line.
31. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
0.09<D2/D1<0.22 (7-1),
where:
D 1 is a axial thickness of the first lens; and
D 2 is a distance between the first and second lenses on the optical axis.
32. The image capturing lens of claim 18 , further satisfying a conditional expression given below:
1.05<TL/f<1.15 (9-1),
where:
TL is a length from the object side surface of the first lens to the image forming surface on the optical axis; and
f is a focal length of the entire system.
33. An image capturing apparatus provided with the image capturing lens of claim 18 .