Imaging lens

Abstract

An imaging lens which uses a larger number of constituent lenses for higher performance and features a low F-value, low-profile design and a wide field of view. Designed for a solid-state image sensor, the imaging lens includes constituent lenses arranged in order from an object side to an image side: a first positive refractive power lens; a second negative refractive power lens; a third lens; a fourth lens; a fifth lens; a sixth lens having a concave image-side surface near an optical axis; and a seventh negative refractive power lens.

Claims

1. An imaging lens comprising, in order from an object side to an image side thereof: a first lens with positive refractive power; a second lens having a concave surface facing the image side near an optical axis; a third lens having at least one aspheric surface; a fourth lens having at least one aspheric surface; a fifth lens having at least one aspheric surface; a sixth lens that is a double-sided aspheric lens and has a concave surface facing the image side near the optical axis; and a seventh lens with negative refractive power that is a double-sided aspheric lens, and has a pole-change point in a position off the optical axis on an image-side aspheric surface thereof; wherein the lenses are arranged with an air gap provided therebetween, and a conditional expression (1) below is satisfied:
50<νd1<70  (1) where: νd1 abbe number of the first lens at d-ray.

2. The imaging lens according to claim 1, wherein a conditional expression (2) below is satisfied:
20<νd2<30  (2) where νd2: abbe number of the second lens at d-ray.

3. The imaging lens according to claim 1, wherein conditional expressions (3) and (4) below are satisfied:
50<νd3<70  (3)
20<νd4<30  (4) where νd3: abbe number of the third lens at d-ray, and νd4: abbe number of the fourth lens at d-ray.

4. The imaging lens according to claim 1, wherein a conditional expression (6) below is satisfied:
0.85<Σd/f<1.25  (6) where Σd: distance along the optical axis from an object-side surface of the first lens to the image-side surface of the seventh lens, and f: focal length of the overall optical system of the imaging lens.

5. The imaging lens according to claim 1, wherein a conditional expression (7) below is satisfied:
0.8<ih/f<1.2  (7) where ih: maximum image height, and f: focal length of the overall optical system of the imaging lens.

6. The imaging lens according to claim 1, wherein conditional expressions (8) and (9) below are satisfied:
0.7<f1/f<1.5  (8)
−5.0<f2/f<−1.0  (9) where f: focal length of the overall optical system of the imaging lens, f1: focal length of the first lens, and f2: focal length of the second lens.

7. The imaging lens according to claim 1, wherein a conditional expression (10) below is satisfied:
2.0<|f34/f|  (10) where f: focal length of the overall optical system of the imaging lens, and f34: composite focal length of the third lens and the fourth lens.

8. The imaging lens according to claim 1, wherein a conditional expression (11) below is satisfied:
0.6<f5/f<1.2  (11) where f: focal length of the overall optical system of the imaging lens, and f5: focal length of the fifth lens.

9. The imaging lens according to claim 1, wherein conditional expressions (13), (14), and (15) below are satisfied:
50<νd5<70  (13)
20<νd6<30  (14)
50<νd7<70  (15) where νd5: abbe number of the fifth lens at d-ray, νd6: abbe number of the sixth lens at d-ray, and νd7: abbe number of the seventh lens at d-ray.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic view showing the general configuration of an imaging lens in Example 1;

(2) FIG. 2 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 1;

(3) FIG. 3 is a schematic view showing the general configuration of an imaging lens in Example 2;

(4) FIG. 4 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 2;

(5) FIG. 5 is a schematic view showing the general configuration of an imaging lens in Example 3;

(6) FIG. 6 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 3;

(7) FIG. 7 is a schematic view showing the general configuration of an imaging lens in Example 4;

(8) FIG. 8 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 4;

(9) FIG. 9 is a schematic view showing the general configuration of an imaging lens in Example 5;

(10) FIG. 10 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 5;

(11) FIG. 11 is a schematic view showing the general configuration of an imaging lens in Example 6;

(12) FIG. 12 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 6;

(13) FIG. 13 is a schematic view showing the general configuration of an imaging lens in Example 7;

(14) FIG. 14 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 7;

(15) FIG. 15 is a schematic view showing the general configuration of an imaging lens in Example 8; and

(16) FIG. 16 shows spherical aberration, astigmatism, and distortion of the imaging lens in Example 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(17) Hereinafter, a preferred embodiment of the present invention will be described in detail referring to the accompanying drawings.

(18) FIGS. 1, 3, 5, 7, 9, 11, 13, and 15 are schematic views showing the general configurations of the imaging lenses according to Examples 1 to 8 of this embodiment respectively. Since all these examples have the same basic configuration, the configuration of an imaging lens according to this embodiment is explained below mainly referring to the schematic view of Example 1.

(19) As shown in FIG. 1, in the imaging lens according to the present invention, elements are arranged in the following order from an object side to an image side: a first lens L1 with positive refractive power having a convex surface on the object side near an optical axis X, a second lens L2 with negative refractive power having a concave surface on the image side near the optical axis X, a third lens L3 with positive refractive power having a convex surface on the image side near the optical axis X, a fourth lens L4 with negative refractive power having a concave surface on the image side near the optical axis X, a fifth lens L5 with positive refractive power as a meniscus lens having a convex surface on the image side near the optical axis X, a sixth lens L6 as a meniscus double-sided aspheric lens having a concave surface on the image side near the optical axis X, and a seventh lens L7 with negative refractive power as a double-sided aspheric lens having a concave surface on the image side near the optical axis X. An aperture stop ST is located on the object side of the first lens L1. Alternatively, the aperture stop ST may be located between the first lens L1 and the second lens L2 as shown in Example 6.

(20) A filter IR is located between the seventh lens L7 and an image plane IMG. This filter IR is omissible. In the present invention, the total track length is evaluated without the filter IR.

(21) The above imaging lens includes four lens groups, namely a first group G1 composed of the first lens L1 and the second lens L2 having positive composite refractive power, a second group G2 composed of the third lens L3 and the fourth lens L4 having positive composite refractive power, a third group G3 composed of the fifth lens L5 having positive refractive power, and a fourth group G4 composed of the sixth lens L6 and the seventh lens L7 having negative composite refractive power so that the refractive power arrangement contributes to a shorter total track length. Alternatively, the second group G2 may have weak negative composite refractive power as shown in Example 4. In each of the first group G1 and the second group G2, the positive lens is located nearer to the object and the negative lens is located nearer to the image plane so that chromatic aberrations generated on the positive lens located nearer to the object are properly corrected by the negative lens located nearer to the image plane. The fifth lens L5 which constitutes the third group G3 has adequate positive refractive power to keep the total track length short and the negative sixth lens L6 and the negative seventh lens L7 which constitute the fourth group G4 have adequate aspheric surfaces to further correct chromatic aberrations and properly correct field curvature and distortion and control the angle of a chief ray incident on the image sensor.

(22) The first lens L1 is a biconvex lens in which the curvature radius of the object-side surface is smaller than the curvature radius of the image-side surface and positive refractive power is adequately distributed to both the surfaces so as to suppress spherical aberrations and provide relatively strong refractive power to achieve compactness of the imaging lens. Alternatively, the image-side surface of the first lens L1 may be concave as shown in Example 4 and in that case, it is desirable that the curvature radius of the image-side surface be larger than the curvature radius of the object-side surface to the extent that the refractive power is not too low and spherical aberrations do not increase.

(23) The second lens L2 is a lens with negative refractive power which has a concave surface on the image side near the optical axis X and corrects spherical aberrations and chromatic aberrations properly.

(24) The third lens L3 is a lens with positive refractive power having a convex surface on the image side near the optical axis X, which corrects field curvature and coma aberrations properly.

(25) The fourth lens L4 is a lens with negative refractive power having a concave surface on the image side near the optical axis X, which corrects residual chromatic aberrations properly.

(26) The fifth lens L5 is a meniscus lens with positive refractive power having a convex surface on the image side near the optical axis X, which has relatively strong positive refractive power. Its refractive power is adequately balanced with the positive refractive power of the first lens L1 so that the imaging lens is compact.

(27) The sixth lens L6 is a meniscus lens having a concave surface on the image side near the optical axis X, which also corrects residual chromatic aberrations properly. The aspheric surfaces on both the sides of the lens correct coma aberrations and astigmatism properly.

(28) The seventh lens L7 is a meniscus lens with negative refractive power having a concave surface on the image side near the optical axis X, which ensures an adequate back focus easily. Due to the aspheric surfaces on both the sides of the lens, the negative refractive power of the seventh lens L7 decreases toward the peripheral portion of the lens and changes to positive refractive power in the peripheral portion. This is effective mainly in correcting distortion and field curvature and controlling the angle of a chief ray incident on the image sensor.

(29) The imaging lens according to the present invention satisfies conditional expressions (1) to (15) below:
50<νd1<70  (1)
20<νd2<30  (2)
50<νd3<70  (3)
20<νd4<30  (4)
0.6<TTL/2ih<1.0  (5)
0.85<Σd/f<1.25  (6)
0.8<ih/f<1.2  (7)
0.7<f1/f<1.5  (8)
−5.0<f2/f<−1.0  (9)
2.0<|f34/f|  (10)
0.6<f5/f<1.2  (11)
−1.2<f67/f<−0.6  (12)
50<νd5<70  (13)
20<νd6<30  (14)
50<νd7<70  (15)

(30) where νd1: Abbe number of the first lens L1 at d-ray, νd2: Abbe number of the second lens L2 at d-ray, νd3: Abbe number of the third lens L3 at d-ray, νd4: Abbe number of the fourth lens L4 at d-ray, TTL: distance on the optical axis x from the objet-side surface of an optical element located nearest to the object to the image plane IMG without the filter IR, etc., ih: maximum image height, f: focal length of the overall optical system of the imaging lens, Σd: distance on the optical axis X from the object-side surface of the first lens L1 to the image-side surface of the seventh lens L7, f1: focal length of the first lens L1, f2: focal length of the second lens L2, f34: composite focal length of the third lens L3 and the fourth lens L4, f5: focal length of the fifth lens L5, f67: composite focal length of the sixth lens L6 and the seventh lens L7, νd5: Abbe number of the fifth lens L5 at d-ray, νd6: Abbe number of the sixth lens L6 at d-ray, and νd7: Abbe number of the seventh lens L7 at d-ray.

(31) In this embodiment, all the lens surfaces are aspheric. The aspheric shapes of these lens surfaces are expressed by the following equation, where Z denotes an axis in the optical axis direction, H denotes a height perpendicular to the optical axis, k denotes a conic constant, and A4, A6, A8, A10, A12, A14, and A16 denote aspheric surface coefficients.

(32) $\begin{array}{cc}Z=\frac{\frac{H^2}{R}}{1+\sqrt{1-\left(k+1\right)\frac{H^2}{R^2}}}+A_4{H}^4+A_6{H}^6+A_8{H}^8+A_{10}{H}^{10}+A_{12}{H}^{12}+A_{14}{H}^{14}+A_{16}{H}^{16}& \mathrm{Equation}1\end{array}$

(33) Next, the imaging lenses in examples according to this embodiment will be explained. In each example, f denotes the focal length of the overall optical system of the imaging lens, Fno denotes an F-number, a denotes a half field of view, ih denotes a maximum image height, and TTL denotes a total track length. i denotes a surface number counted from the object side, r denotes a curvature radius, d denotes the distance between lens surfaces on the optical axis X (surface distance), Nd denotes a refractive index with respect to d-ray (reference wavelength), and νd denotes an Abbe number with respect to d-ray. As for aspheric surfaces, an asterisk (*) after surface number i indicates that the surface concerned is an aspheric surface.

Example 1

(34) The basic lens data of Example 1 is shown below in Table 1.

(35) TABLE-US-00001 TABLE 1 Example 1 in mm f = 6.76 Fno = 2.40 ω(°) = 41.2 lh = 5.99 TTL = 9.97 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.15  2* 5.902 0.760 1.5438 55.57  3* −13.378 0.040  4* 4.196 0.576 1.6142 25.58  5* 2.657 0.692  6* 28.468 1.381 1.5438 55.57  7* −5.000 0.093  8* −7.763 0.700 1.6142 25.58  9* 36.656 0.389 10* −4.775 1.270 1.5346 56.16 11* −1.976 0.053 12* 14.503 0.790 1.6142 25.58 13* 7.785 0.402 14* 6.1147 1.000 1.5346 56.16 15* 2.1731 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.834 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 7.64 2 4 −13.74 3 6 7.94 4 8 −10.37 5 10 5.45 6 12 −28.64 7 14 −6.92 Lens Composite Focal Length Third Lens-Fourth Lens 30.08 Sixth Lens-Seventh Lens −5.43 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4  4.733E−04  7.844E−03 −1.319E−02 −2.924E−02 −2.453E−03 −1.052E−03 −1.594E−02 A6 −1.803E−04  5.631E−04  5.781E−03  7.339E−03 −1.303E−03 −1.235E−03  1.226E−03 A8 −1.476E−04 −1.398E−03 −2.083E−03 −1.724E−03  3.330E−04  7.037E−05  1.055E−04 A10  2.594E−05  2.751E−04  2.493E−04  1.331E−04  0.000E+00  0.000E+00 −1.756E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.678E+00  0.000E+00  0.000E+00  0.000E+00 −4.569E+00 A4 −1.427E−02  3.293E−03 −8.922E−03  7.763E−04 −2.354E−03 −1.419E−02 −7.740E−03 A6  1.694E−03  1.077E−03  1.393E−03 −4.500E−04 −1.456E−04  5.646E−04 4.2746E−01 A8 −1.569E−04 −1.025E−04  9.563E−05  2.340E−05  3.430E−06  6.271E−06 −2.000E−05 A10  8.620E−06  2.582E−06 −1.118E−05 −2.545E−06 −1.713E−07 −9.263E−07  4.987E−07 A12  0.000E+00  0.000E+00 −6.577E−07  1.037E−07  2.734E−08  1.374E−08 −8.500E−09 A14  0.000E+00  0.000E+00  6.246E−08  0.000E+00 −7.675E−10  2.642E−10  9.622E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+22  0.000E+02  6.317E−12  0.000E+00

(36) As shown in Table 9, the imaging lens in Example 1 satisfies all the conditional expressions (1) to (15).

(37) FIG. 2 shows spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in Example 1. The spherical aberration diagram shows the amount of aberration at wavelengths of F-ray (486 nm), d-ray (588 nm), and C-ray (656 nm). The astigmatism diagram shows the amount of aberration on sagittal image surface S and the amount of aberration on tangential image surface T (the same is true for FIGS. 4, 6, 8, 10, 12, 14, and 16). As shown in FIG. 2, each aberration is properly corrected.

(38) The imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.83, so it achieves compactness though it uses seven constituent lenses.

Example 2

(39) The basic lens data of Example 2 is shown below in Table 2.

(40) TABLE-US-00002 TABLE 2 Example 2 in mm f = 6.76 Fno = 2.40 ω(°) = 41.2 lh = 5.99 TTL = 9.57 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.185  2* 4.594 0.823 1.5438 55.57  3* −16.373 0.040  4* 5.408 0.500 1.6142 25.58  5* 3.185 0.681  6* −96.794 1.070 1.5346 56.16  7* −5.000 0.050  8* −13.759 0.700 1.6142 25.58  9* 25.844 0.402 10* −3.482 1.170 1.5346 56.16 11* −1.955 0.053 12* 9.153 0.790 1.6142 25.58 13* 5.035 0.558 14* 5.922 1.055 1.5346 56.16 15* 2.448 0.700 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.786 Image plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 6.69 2 4 −13.80 3 6 9.82 4 8 −14.52 5 10 6.58 6 12 −19.65 7 14 −8.73 Lens Composite Focal Length Third Lens-Fourth Lens 29.34 Sixth Lens-Seventh Lens −5.79 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4 −5.727E−04  5.079E−03 −1.136E−02 −2.352E−02 −5.571E−03 −1.838E−03 −1.684E−02 A6 −9.186E−04 −9.582E−04  4.624E−03  5.871E−03 −1.228E−03 −2.322E−03  1.436E−04 A8  1.113E−04 −1.166E−03 −2.286E−03 −1.751E−03 −1.266E−04 −1.902E−05 −3.751E−04 A10 −1.114E−04  1.777E−04  3.469E−04  1.681E−04  0.000E+00  0.000E+00  5.333E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.608E+00  0.000E+00  0.000E+00  0.000E+00 −5.026E+00 A4 −1.445E−02  2.918E−03 −1.281E−02 −5.078E−04 −5.777E−03 −1.507E−02 −8.309E−03 A6  9.193E−04  2.119E−03  2.149E−03 −5.507E−04 −1.324E−04  5.716E−04  4.648E−04 A8 −1.649E−04 −2.564E−05  1.211E−04  1.930E−05  4.101E−06  7.109E−06 −1.959E−05 A10  2.366E−05 −7.078E−06 −1.420E−05 −2.678E−06 −1.940E−07 −9.253E−07  5.065E−07 A12  0.000E+00  0.000E+00 −9.250E−07  1.477E−07  2.571E−08  1.295E−08 −7.576E−09 A14  0.000E+00  0.000E+00  6.974E−08  0.000E+00 −7.787E−10  2.428E−10  6.471E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 −5.500E−12  0.000E+00

(41) As shown in Table 9, the imaging lens in Example 2 satisfies all the conditional expressions (1) to (15).

(42) FIG. 4 shows various aberrations of the imaging lens in Example 2. As shown in FIG. 4, each aberration is corrected properly.

(43) The imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.80, so it achieves compactness though it uses seven constituent lenses.

Example 3

(44) The basic lens data of Example 3 is shown below in Table 3.

(45) TABLE-US-00003 TABLE 3 Example 3 in mm f = 6.78 Fno = 2.41 ω(°) = 41.1 lh = 5.99 TTL = 9.29 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.13  2* 5.019 0.774 1.5438 55.57  3* −6.745 0.068  4* 8.549 0.532 1.6349 23.97  5* 3.069 0.700  6* 286.557 0.886 1.5346 56.16  7* −8.403 0.053  8* 7.117 0.600 1.6349 23.97  9* 5.614 0.651 10* −3.969 1.097 1.5346 56.16 11* −1.906 0.053 12* 11.711 0.670 1.6349 23.97 13* 4.996 0.529 14* 6.2287 1.042 1.5346 56.16 15* 2.4479 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.641 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 5.42 2 4 −7.83 3 6 15.29 4 8 −49.56 5 10 5.79 6 12 −14.27 7 14 −8.34 Lens Composite Focal Length Third Len-Fourth Lens 20.81 Sixth Lens-Seventh Lens −4.95 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4 −7.763E−03  6.959E−03 −3.606E−03 −2.401E−02  1.186E−03  8.779E−03 −1.347E−02 A6 −3.872E−03 −5.264E−03  5.475E−03  9.046E−03 −2.126E−03 −2.563E−03  9.691E−04 A8  4.450E−04  4.640E−04 −1.164E−03 −1.964E−03  4.475E−05 −1.037E−04 −1.584E−04 A10 −1.920E−04 −8.594E−05  1.225E−04  1.736E−04  0.000E+00  0.000E+00 −5.195E−06 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.633E+00  0.000E+00  0.000E+00  0.000E+00 −5.411E+00 A4 −1.794E−02  5.886E−04 −1.181E−02  4.673E−04 −5.650E−03 −1.406E−02 −8.527E−03 A6  1.660E−03  1.859E−03  1.900E−03 −6.221E−04 −1.948E−04  5.627E−04  4.941E−04 A8 −1.751E−04 −3.802E−05  1.326E−04  1.822E−05  9.028E−06  6.413E−06 −2.174E−05 A10  6.551E−06 −4.465E−06 −1.209E−05 −2.795E−06 −1.947E−07 −9.378E−07  5.371E−07 A12  0.000E+00  0.000E+00 −8.523E−07  1.742E−07  2.122E−08  1.374E−08 −5.955E−09 A14  0.000E+00  0.000E+00  5.879E−08  0.000E+00 −8.130E−10  2.642E−10  3.567E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 −5.954E−12  0.000E+00

(46) As shown in Table 9, the imaging lens in Example 3 satisfies all the conditional expressions (1) to (15).

(47) FIG. 6 shows various aberrations of the imaging lens in Example 3. As shown in FIG. 6, each aberration is corrected properly.

(48) In addition, the imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.78, so it achieves compactness though it uses seven constituent lenses.

Example 4

(49) The basic lens data of Example 4 is shown below in Table 4.

(50) TABLE-US-00004 TABLE 4 Example 4 in mm f = 6.91 Fno = 2.40 ω(°) = 40.5 lh = 5.99 TTL = 9.51 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.2  2* 3.909 0.727 1.5438 55.57  3* 500.000 0.053  4* 4.925 0.450 1.6349 73.97  5* 3.448 0.603  6* −57.008 1.105 1.5438 55.57  7* −5.000 0.317  8* −5.137 0.600 1.6349 23.97  9* 113.766 0.173 10* −5.583 1.255 1.5346 56.16 11* −2.301 0.053 12* 6.823 0.737 1.6349 23.97 13* 6.696 1.028 14* 44.7468 1.000 1.5346 56.16 15* 3.2663 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.422 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 7.24 2 4 −20.54 3 6 10.00 4 8 −7.73 5 10 6.46 6 12 451.08 7 14 −6.65 Lens Composite Focal Length Third Lens-Fourth Lens −38.39 Sixth Lens-Seventh Lens −7.07 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4  2.504E−03  4.631E−03 −1.322E−02 −2.172E−02 −8.638E−03 −2.794E−03 −1.772E−02 A6 −6.007E−04  1.143E−03  4.807E−03  4.213E−03 −1.861E−03 −2.571E−03 −3.861E−04 A8  5.905E−04 −1.217E−03 −2.279E−03 −1.538E−03 −2.196E−04 −3.078E−04 −4.941E−04 A10 −1.954E−04  2.229E−05  1.741E−04  1.088E−04  0.000E+00  0.000E+00  3.213E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.803E+00  0.000E+00  0.000E+00  0.000E+00 −6.299E+00 A4 −1.741E−02 −1.542E−01 −1.114E−02 −1.283E−03 −3.696E−03 −1.326E−02 −8.438E−03 A6  1.286E−03  1.571E−03  1.826E−03 −5.200E−04 −2.537E−04  5.940E−04  5.314E−04 A8 −1.585E−04 −4.206E−05  1.158E−04  2.243E−05  5.157E−06  7.406E−06 −2.122E−05 A10  2.416E−05 −4.702E−06 −1.314E−05 −2.367E−06 −1.905E−07 −9.038E−07  4.927E−07 A12  0.000E+00  0.000E+00 −8.268E−07  1.112E−07  2.684E−08  1.326E−08 −7.646E−09 A14  0.000E+00  0.000E+00  6.918E−08  0.000E+00 −5.278E−10  1.455E−10  7.431E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  3.430E−12  0.000E+00

(51) As shown in Table 9, the imaging lens in Example 4 satisfies all the conditional expressions (1) to (15).

(52) FIG. 8 shows various aberrations of the imaging lens in Example 4. As shown in FIG. 8, each aberration is corrected properly.

(53) In addition, the imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.79, so it achieves compactness though it uses seven constituent lenses.

Example 5

(54) The basic lens data of Example 5 is shown below in Table 5.

(55) TABLE-US-00005 TABLE 5 Example 5 in mm f = 6.878 Fno = 2.40 ω(°) = 40.7 lh = 5.99 TTL = 9.51 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.15  2* 4.675 0.859 1.5438 55.57  3* −8.414 0.062  4* −200.000 0.450 1.6349 23.97  5* 7.659 0.786  6* −21.168 0.691 1.5438 55.57  7* −7.732 0.050  8* 21.372 0.600 1.6349 23.97  9* 9.658 0.490 10* −3.936 1.255 1.5346 56.16 11* −1.916 0.053 12* 10.446 0.700 1.6349 23.97 13* 4.872 0.620 14* 5.8439 1.076 1.5146 56.16 15* 2.3606 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.825 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 5.66 2 4 −11.61 3 6 22.00 4 8 −28.32 5 10 5.74 6 12 −15.12 7 14 −8.30 Lens Composite Focal Length Third Lens-Fourth Lens 91.65 Sixth Lens-Seventh Lens −5.03 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4 −2.432E−03  4.564E−03 −8.319E−03 −2.155E−02 −7.998E−03  2.520E−03 −1.669E−02 A6 −2.089E−03 −2.681E−04  5.956E−03  5.035E−03 −2.370E−03 −2.179E−03  3.460E−04 A8  7.323E−04 −1.270E−03 −2.557E−03 −1.393E−03  6.397E−05 −1.145E−04 −3.424E−04 A10 −3.283E−04 −5.908E−05  1.074E−04  1.608E−05  0.000E+00  0.000E+00  1.356E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.666E+00  0.000E+00  0.000E+00  0.000E+00 −4.955E+00 A4 −1.691E−02  1.727E−03 −1.334E−02 −3.078E−04 −6.574E−03 −1.543E−02 −8.384E−03 A6  9.317E−04  1.965E−03  1.895E−03 −5.628E−04 −9.109E−05  5.717E−04  4.834E−04 A8 −1.628E−04 −4.420E−05  1.214E−04  1.934E−05  5.202E−06  7.067E−06 −2.101E−05 A10  2.288E−05 −8.083E−06 −1.279E−05 −2.787E−06 −2.477E−07 −9.246E−07  4.973E−07 A12  0.000E+00  0.000E+00 −7.944E−07  1.451E−07  2.263E−08  1.347E−08 −7.305E−09 A14  0.000E+00  0.000E+00  7.298E−08  0.000E+00 −7.679E−10  2.033E−10  8.752E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  4.363E−12  0.000E+00

(56) As shown in Table 9, the imaging lens in Example 5 satisfies all the conditional expressions (1) to (15).

(57) FIG. 10 shows various aberrations of the imaging lens in Example 5. As shown in FIG. 10, each aberration is corrected properly.

(58) In addition, the imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.79, so it achieves compactness though it uses seven constituent lenses.

Example 6

(59) The basic lens data of Example 6 is shown below in Table 6.

(60) TABLE-US-00006 TABLE 6 Example 6 in mm f = 06.784 Fno = 2.41 ω(°) = 41.1 lh = 5.99 TTL = 9.79 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity  1* 6.551 0.656 1.5438 55.57  2* −19.094 −0.009 3 (Stop) Infinity 0.050  4* 3.420 0.465 1.6142 25.58  5* 2.777 0.592  6* −61.014 1.211 1.5346 56.16  7* −3.500 0.052  8* −7.043 0.867 1.6142 25.58  9* 20.788 0.503 10* −3.693 1.224 1.5346 56.16 11* −1.929 0.053 12* 16.832 0.829 1.6142 25.58 13* 7.928 0.537 14* 6.4006 1.000 1.5346 56.16 15* 2.3387 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.773 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 1 9.05 2 4 −33.18 3 6 6.89 4 3 −8.46 5 10 6.08 6 12 −25.30 7 14 −7.54 Lens Composite Focal Length Third Lens-Fourth Lens 34.16 Sixth Lens-Seventh Lens −5.61 Aspheric Surface Data 1st Surface 2nd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4  2.835E−03  4.028E−03 −1.959E−02 −2.873E−02 −1.476E−03 −4.280E−04 −2.070E−02 A6 −1.993E−03 −3.504E−04  4.377E−03  4.153E−03 −1.217E−03 −2.006E−03  5.450E−05 A8  7.500E−04 −4.328E−04 −1.640E−03 −1.392E−03 −1.763E−04 −2.511E−04 −4.224E−04 A10 −1.947E−04 −2.621E−05  7.274E−05  4.673E−05  0.000E+00  0.000E+00  5.841E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.602E+00  0.000E+00  0.000E+00  0.000E+00 −4.830E+00 A4 −1.648E−02  1.209E−03 −1.182E−02  2.749E−03 −3.373E−03 −1.657E−02 −8.723E−03 A6  1.379E−03  1.954E−03  1.760E−03 −7.283E−04 −1.473E−04  6.112E−04  5.285E−04 A8 −1.328E−04 −3.294E−05  1.226E−04  3.110E−05  5.120E−06  8.132E−06 −2.169E−05 A10  1.979E−05 −4.819E−06 −1.221E−05 −1.901E−05 −2.920E−07 −9.332E−07  5.060E−07 A12  0.000E+00  0.000E+00 −8.281E−07  6.359E−08  2.409E−08  1.231E−08 −6.843E−09 A14  0.000E+00  0.000E+00  5.965E−08  0.000E+00 −5.741E−10  2.203E−10  5.440E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 −4.533E−12  0.000E+00

(61) As shown in Table 9, the imaging lens in Example 6 satisfies all the conditional expressions (1) to (15).

(62) FIG. 12 shows various aberrations of the imaging lens in Example 6. As shown in FIG. 12, each aberration is corrected properly.

(63) The imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.82, so it achieves compactness though it uses seven constituent lenses.

Example 7

(64) The basic lens data of Example 7 is shown below in Table 7.

(65) TABLE-US-00007 TABLE 7 Example 7 in mm F = 3.452 Fno = 2.01 ω(°) = 40.0 lh = 2.93 TTL = 4.82 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.12  2* 2.409 0.531 1.5438 55.57  3* −7.584 0.020  4* 3.487 0.290 1.6349 23.97  5* 1.921 0.360  6* −21.075 0.509 1.5346 56.16  7* −3.212 0.025  8* −9.795 0.300 1.6349 23.97  9* 47.382 0.204 10* −1.594 0.554 1.5346 56.16 11* −0.855 0.026 12* 3.668 0.317 1.6349 23.97 13* 2.395 0.131 14* 2.8544 0.430 1.5346 56.16 15* 1.0356 0.400 16 Infinity 0.210 1.5640 51.30 17 Infinity 0.589 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 3.43 2 4 −7.26 3 6 7.02 4 8 −12.76 5 10 2.74 6 12 −12.03 7 14 −3.31 Lens Composite Focal Length Third Lens-Fourth Lens 15.60 Sixth Lens-Seventh Lens −2.56 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4 −6.534E−04 −1.764E−03 −1.274E−01 −1.846E−01 −5.965E−02 −8.331E−02 −1.701E−01 A6 −2.111E−02  6.379E−02  1.520E−01  1.112E−01 −8.220E−02 −4.934E−02  2.576E−02 A8  3.737E−02 −1.818E−01 −2.428E−01 −1.432E−01  1.301E−02  1.734E−02 −7.037E−03 A10 −5.338E−02  5.655E−02  6.957E−02  2.448E−02  0.000E+00  0.000E+00  2.402E−03 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.790E+00  0.000E+00  0.000E+00  0000E+00 −5.955E+00 A4 −1.195E−01  8.022E−02 −9.767E−02 −4.089E−02 −7.313E−02 −1.260E−01 −7.527E−02 A6  4.895E−02  5.987E−02  8.116E−02 −1.783E−02 −6.540E−03  2.021E−02  2.177E−02 A8 −3.118E−02 −4.834E−03  1.606E−02  4.733E−03  1.498E−03  1.023E−03 −3.616E−03 A10  1.489E−02 −3.066E−03 −9.396E−03 −1.866E−03 −2.527E−05 −5.930E−04  2.765E−04 A12  0.000E+00  0.000E+00 −2.518E−03  3.970E−04  6.254E−05  3.388E−05 −1.611E−05 A14  0.000E+00  0.000E+00  8.407E−04  0.000E+00 −1.195E−05  3.746E−06  1.267E−06 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 −3.570E−07  0.000E+00

(66) As shown in Table 9, the imaging lens in Example 7 satisfies all the conditional expressions (1) to (15).

(67) FIG. 14 shows various aberrations of the imaging lens in Example 7. As shown in FIG. 14, each aberration is corrected properly.

(68) In addition, the imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.0. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.82, so it achieves compactness though it uses seven constituent lenses.

Example 8

(69) The basic lens data of Example 8 is shown below in Table 8.

(70) TABLE-US-00008 TABLE 8 Example 8 in mm f = 6.781 Fno = 2.41 ω(°) = 41.1 lh = 5.99 TTL = 9.53 Surface Data Curvature Surface Refractive Abbe Surface No. I Radius r Distance d Index Nd Number vd (Object Surface) Infinity Infinity 1 (Stop) Infinity −0.13  2* 5.591 0.683 1.5438 55.57  3* −9.809 0.040  4* 5.913 0.545 1.6349 23.97  5* 3.081 0.721  6* −50.310 1.051 1.5438 55.57  7* −5.000 0.050  8* 10.044 0.600 1.6349 23.97  9* 6.265 0.646 10* −3.634 1.187 1.5438 55.57 11* −1.933 0.053 12* 12.725 0.700 1.6349 23.97 13* 5.078 0.559 14* 6.6328 1.048 1.5438 55.57 15 2.5287 0.800 16 Infinity 0.300 1.5640 51.30 17 Infinity 0.651 Image Plane Infinity Constituent Lens Data Lens Start Surface Focal Length 1 2 6.65 2 4 −10.95 3 6 10.13 4 8 −27.95 5 10 6.09 6 12 −13.80 7 14 −8.26 Lens Composite Focal Length Third Lens-Fourth Lens 15.02 Sixth Lens-Seventh Lens −4.84 Aspheric Surface Data 2nd Surface 3rd Surface 4th Surface 5th Surface 6th Surface 7th Surface 8th Surface k  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A4 −4.481E−03  5.909E−03 −7.624E−03 −2.388E−02 −1.587E−03  3.146E−03 −1.446E−02 A6 −2.518E−03 −2.178E−03  5.403E−03  7.201E−03 −2.098E−03 −2.274E−03  7.969E−04 A8  6.727E−04 −5.293E−04 −1.979E−03 −1.836E−03  4.720E−05 −1.889E−05 −1.764E−04 A10 −2.386E−04  3.757E−05  2.468E−04  1.481E−04  0.000E+00  0.000E+00  1.096E−05 A12  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A14  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 9th Surface 10th Surface 11th Surface 12th Surface 13th Surface 14th Surface 15th Surface k  0.000E+00  0.000E+00 −2.635E+00  0.000E+00  0.000E+00  0.000E+00 −5.592E+00 A4 −1.687E−02  1.502E−03 −1.141E−02 −2.939E−04 −6.354E−03 −1.420E−02 −8.556E−03 A6  1.362E−03  2.005E−03  1.870E−03 −5.167E−04 −1.230E−04  5.713E−04  5.076E−04 A8 −1.744E−04 −3.060E−05  1.255E−04  1.423E−05  7.868E−06  6.648E−06 −2.127E−05 A10  1.325E−05 −4.709E−06 −1.251E−05 −2.682E−06 −2.382E−07 −9.358E−07  5.086E−07 A12  0.000E+00  0.000E+00 −8.425E−07  1.745E−07  2.180E−08  1.327E−08 −6.517E−09 A14  0.000E+00  0.000E+00  6.556E−08  0.000E+00 −7.869E−10  2.601E−10  5.919E−11 A16  0.000E+00  0.000E+00  0.000E+00  0.000E+00  0.000E+00 −5.510E−12  0.000E+00

(71) As shown in Table 9, the imaging lens in Example 8 satisfies all the conditional expressions (1) to (15).

(72) FIG. 16 shows various aberrations of the imaging lens in Example 8. As shown in FIG. 16, each aberration is corrected properly.

(73) In addition, the imaging lens provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.4. The ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.79, so it achieves compactness though it uses seven constituent lenses.

(74) As explained above, the imaging lenses according to this embodiment of the present invention realize an imaging lens system which provides a wide field of view of 80 degrees or more and high brightness with an F-value of 2.0 to 2.4 and corrects aberrations properly. In addition, the ratio of total track length TTL to maximum image height ih (TTL/2ih) is 0.85 or less, offering a compact lens system.

(75) Table 9 shows data on Examples 1 to 8 in relation to the conditional expressions (1) to (15).

(76) TABLE-US-00009 TABLE 9 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Conditional Expression (1) 55.57 55.57 55.57 55.57 55.57 55.57 55.57 55.57 50 < vd1 < 70 Conditional Expression (2) 25.58 25.58 23.97 23.97 23.97 25.58 23.97 23.97 20 < vd2 < 30 Conditional Expression (3) 55.57 56.16 56.16 55.57 55.57 56.16 56.16 55.57 50 < vd3 < 70 Conditional Expression (4) 25.58 25.58 23.97 23.97 23.97 25.58 23.97 23.97 20 < vd4 < 30 Conditional Expression (5) 0.83 0.80 0.78 0.79 0.79 0.82 0.82 0.79 0.6 < TTL/2 lh < 1.0 Conditional Expression (6) 1.20 1.17 1.13 1.17 1.12 1.18 1.07 1.16 0.85 < Σd/f < 1.25 Conditional Expression (7) 0.89 0.89 0.88 0.87 0.87 0.88 0.85 0.88 0.8 < lh/f < 1.2 Conditional Expression (8) 1.13 0.99 0.80 1.05 0.82 1.33 0.99 0.98 0.7 < f1/f < 1.5 Conditional Expression (9) −2.03 −2.04 −1.16 −2.97 −1.69 −4.89 −2.10 −1.61 −5.0 < f2/f < −1.0 Conditional Expression (10) 4.45 4.34 3.07 5.55 13.33 5.04 4.52 2.22 2.0 < | f34/f | Conditional Expression (11) 0.81 0.97 0.85 0.93 0.83 0.90 0.79 0.90 0.6 < f5/f < 1.2 Conditional Expression (12) −0.80 −0.86 −0.73 −1.02 −0.73 −0.83 −0.74 −0.71 −1.2 < f67/f < −0.6 Conditional Expression (13) 56.16 56.16 56.16 56.16 56.16 56.16 56.16 55.57 50 < vd5 < 70 Conditional Expression (14) 25.58 25.58 23.97 23.97 23.97 25.58 23.97 23.97 20 < vd6 < 30 Conditional Expression (15) 56.16 56.16 56.16 56.16 56.16 56.16 56.16 55.57 50 < vd7 < 70

(77) The imaging lens composed of seven constituent lenses according to the present invention features compactness and a wide field of view and meets the demand for high resolution. Particularly when it is used in a highly functional product such as a smart TV or 4K TV, or an information terminal such as a game console or PC, or an increasingly compact and low-profile mobile terminal such as a smart phone, mobile phone or PDA (Personal Digital Assistant), it enhances the performance of the product in which it is mounted.

(78) The effects of the present invention are as follows.

(79) According to the present invention, it is possible to provide a high-brightness compact imaging lens which delivers higher optical performance than conventional imaging lenses when it is used not only in a conventional small image sensor but also in a large image sensor, and provides a wide field of view and can correct various aberrations properly.