KR102345282B1 - High definition lens system - Google Patents

Abstract

The present invention relates to a wide-angle lens system composed of a total of 5 lenses, comprising a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged in order from an object side, wherein the first The lens has a convex object-side surface and has positive refractive power, the fifth lens has a concave image-side surface, and all of the first to fifth lenses have aspherical surfaces, and The dispersion constant V2, the dispersion constant V4 of the fourth lens, and the dispersion constant V5 of the fifth lens satisfy V2+V3+V4+V5 < 115 as a technical gist of the high-resolution lens system. Accordingly, it is possible to provide a high-resolution compact lens system by appropriately designing the refractive power, shape, and dispersion constant of the lens to correct chromatic aberration while being compact and lightweight.

Description

High definition lens system

The present invention relates to a wide-angle lens system composed of a total of 5 lenses, and in particular, by appropriately designing the refractive power, shape, dispersion constant, etc. of the lens, it is compact and lightweight and can provide a high-resolution image by correcting chromatic aberration, It relates to a high-resolution lens system capable of obtaining a wide-angle image.

Recent portable terminals are equipped with cameras to enable video calls and photo taking. In addition, as the function occupied by the camera in the portable terminal gradually increases, the demand for high resolution and wide angle of the camera for the portable terminal is gradually increasing, and there is a trend to require miniaturization for convenient portability.

In order to realize these high-definition, high-performance, and miniaturization functions, the lens of the camera is recently made of a plastic material that is lighter than glass, and a lens system is composed of 5 or more lenses to realize high-resolution.

In particular, a small lens mounted on a smartphone is advantageous as the total track length of the lens system is shorter due to the limitation of the thickness of the smartphone.

In the case of the lens system exemplified in US Pat. No. 9,874,720 shown in FIG. 1, the TTL (distance from the front of the lens to the image plane) related to the length of the lens is 4.79, which is a long lens system, applied to a thin smartphone There is a limit to this.

The present invention is to solve the above problems, and it is an object of the present invention to provide a high-resolution lens system that provides a high-resolution image by appropriately designing the refractive power, shape, dispersion constant, etc. of the lens to correct chromatic aberration while being compact and lightweight. .

In order to achieve the above object, the present invention includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in order from an object side, wherein the first lens has an object side surface It has a convex shape and has a positive refractive power, and the fifth lens has a concave image side surface, and the dispersion constant V2 of the second lens, the dispersion constant V4 of the fourth lens, and the dispersion constant V5 of the fifth lens are, A high-resolution lens system that satisfies V2+V3+V4+V5 < 115 is a technical gist.

In addition, the dispersion constant V2 of the second lens and the dispersion constant V5 of the fifth lens preferably satisfy V2+V5<60.

In addition, it is preferable that the diameter EPD of the entrance pupil of the lens system and the image plane height ImagH satisfy 0.5<EPD/ImagH<1.0.

The present invention relates to a lens system in which a first lens, a second lens, a third lens, a fourth lens and a fifth lens are arranged from an object along an optical axis by appropriately designing the refractive power, shape, and dispersion constant of the lens. , it is possible to provide a high-resolution, high-resolution lens system that can be easily applied to a small-sized, lightweight, chromatic aberration-corrected, thin or small-sized camera module, especially a smartphone due to its short TTL.

In particular, by using a high refractive material for the second lens, the third lens, the fourth lens, and the fifth lens, it is possible to provide a high-resolution small lens system by compensating for chromatic aberration and improving performance.

1 - A schematic diagram of a conventional high-resolution lens system.
2 - A diagram showing a first embodiment of a high-resolution lens system according to the present invention.
3 - A diagram showing an aberration diagram according to the first embodiment of the present invention.
4 - A view showing a second embodiment of the compact wide-angle lens system according to the present invention.
5 - A diagram showing an aberration diagram according to a second embodiment of the present invention.
6 - A diagram showing a third embodiment of a compact wide-angle lens system according to the present invention.
7 - A diagram showing an aberration diagram according to a third embodiment of the present invention.
8 - A diagram showing a fourth embodiment of a compact wide-angle lens system according to a fourth embodiment of the present invention.
9 - A diagram showing an aberration diagram according to a fourth embodiment of the present invention.

The present invention relates to a lens system composed of a total of five lenses, and to a lens system arranged with a first lens, a second lens, a third lens, a fourth lens, and a fifth lens from an object along an optical axis.

In addition, by appropriately designing the refractive power, shape, and dispersion constant of the lens, it is compact and lightweight, and chromatic aberration is corrected. It is to provide a high-resolution lens system.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. 2 is a diagram showing an embodiment of a high-resolution lens system according to the present invention, and FIG. 3 is a diagram showing an aberration diagram according to an embodiment of the present invention.

As shown, the present invention includes a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4), and a fifth lens (L5) arranged in order from the object side and the first lens (L1) has a convex object-side surface, has positive refractive power, and the fifth lens (L5) has a concave image-side surface, and the first to fifth lenses ( L1 to L5) are all composed of aspherical surfaces

This is to ensure that the positive and negative refractive powers of each lens constituting the lens system are evenly distributed, so that it is possible to realize high performance suitable for a small lens system.

In particular, in the present invention, the dispersion constant V2 of the second lens L2, the dispersion constant V4 of the fourth lens L4, and the dispersion constant V5 of the fifth lens L5 satisfy V2+V3+V4+V5 < 115. characterized in that

Accordingly, the second lens (L2), the third lens (L3), the fourth lens (L4), and the fifth lens (L5) are made of a high refractive material to compensate for chromatic aberration and improve the performance of the high-resolution small lens system. suitable for

In addition, according to the present invention, the dispersion constant V2 of the second lens and the dispersion constant V5 of the fifth lens satisfy V2+V5 < 60, thereby minimizing chromatic aberration to provide a high-resolution image.

In addition, in the lens system according to the present invention, the diameter EPD of the entrance pupil and the image plane height ImagH satisfy 0.5 < EPD/ImagH < 1.7, which is advantageous in designing a small lens system.

In addition, the first to fifth lenses L1 to L5 are formed of a plastic material, and all are formed of an aspherical surface, so that spherical aberration and chromatic aberration can be corrected, and each lens has an advantageous refractive index for reducing the length. It is formed of a material, and a material in which a dispersion constant is appropriately distributed to be advantageous for chromatic aberration correction is used.

As described above, the present invention relates to a lens system composed of a total of five lenses, and a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4) and It relates to a lens system arranged as a fifth lens (L5).

As a result, the refractive power, shape, and dispersion constant of the lens are appropriately designed, so that the chromatic aberration is corrected while being small and light. to provide a system.

In particular, by using a high refractive material for the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5, a high-resolution small lens system through compensation of chromatic aberration and performance improvement suitable for

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

<First embodiment>

2 shows a first embodiment of a high-resolution wide-angle small lens system according to the present invention.

As shown, in the order of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 from the object along the optical axis. will be placed

Table 1 below shows numerical data of lenses constituting the lens system according to the first embodiment of the present invention.

Surface RDY (radius of curvature) THI (thickness) Nd (index of refraction) Vd (Abesu) Object Infinity 400.00 One Infinity 0.00 2 1.66 0.60 1.5441 56.0 3 63.78 0.05 Stop 4.94 0.20 1.6500 21.5 5 2.16 0.18 6 Infinity 0.09 7 97.84 0.42 1.5850 30.0 8 -5.30 0.30 9 5.34 0.46 1.6150 25.9 10 2.61 0.30 11 1.16 0.59 1.5850 30.0 12 1.08 0.30 13 Infinity 0.21 1.5168 64.2 14 Infinity 0.56 Image Infinity 0.01

As shown in FIG. 2 , the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , and the fifth lens L5 are disposed from the object side. , when the optical axis direction is set as X and the direction orthogonal to the optical axis is set as Y axis, the aspherical expression is as follows.

The aspherical surface is a curved surface obtained by rotating the curve obtained by the aspherical expression of Equation 1 about the optical axis, R is the radius of curvature, K is the conic constant, A ₃ , A ₄ , A ₅ , A ₆ ,..., A ₁₄ is the aspheric coefficient.

From Equation 1, aspheric coefficients having data of each of the above lenses are shown in Table 2 below.

s2 s3 s4 s5 s7 s8 s9 s10 s11 s12 K -2.E+00 -7.E+01 -3.E+01 -7.E+00 3.E+01 -3.E+01 -1.E+02 -1.E+02 -9.E+00 -4.E+00 A3 1.E-02 -7.E-01 -9.E-01 -4.E-01 -2.E-01 -1.E-01 -5.E-02 7.E-02 -1.E-01 -1.E-01 A4 2.E-01 3.E+00 5.E+00 1.E+00 1.E-01 -1.E-03 6.E-01 7.E-02 8.E-02 9.E-04 A5 -2.E+00 -9.E+00 -2.E+01 6.E+00 -1.E+00 -3.E-01 -3.E+00 -3.E-01 -3.E-02 6.E-02 A6 7.E+00 1.E+01 5.E+01 -7.E+01 9.E+00 6.E-01 7.E+00 4.E-01 1.E-02 -4.E-02 A7 -2.E+01 3.E+01 -2.E+02 3.E+02 -4.E+01 2.E+00 -9.E+00 -3.E-01 -2.E-03 1.E-02 A8 3.E+01 -2.E+02 5.E+02 -8.E+02 9.E+01 -6.E+00 9.E+00 1.E-01 4.E-04 -2.E-03 A9 -3.E+01 3.E+02 -1.E+03 1.E+03 -1.E+02 8.E+00 -5.E+00 -2.E-02 -4.E-05 3.E-04 A10 2.E+01 -3.E+02 1.E+03 -1.E+03 1.E+02 -5.E+00 2.E+00 3.E-03 3.E-06 -1.E-05 A11 -3.E+00 1.E+02 -4.E+02 4.E+02 -4.E+01 9.E-01 -3.E-01 -2.E-04 -1.E-07 3.E-07

Here, the dispersion constant V2 of the second lens L2, the dispersion constant V4 of the fourth lens L4, and the dispersion constant V5 of the fifth lens L5 satisfy V2+V3+V4+V5 = 107.4, and , the dispersion constant V2 of the second lens L2 and the dispersion constant V5 of the fifth lens L5 satisfy V2+V5 = 51.5, and the diameter of the entrance pupil of the lens system EPD and the image plane height ImagH are EPD/ ImagH = 0.51 is satisfied.

3 shows an aberration diagram according to a first embodiment of the present invention.

The first data of FIG. 3 shows spherical aberration, the horizontal axis indicates the focus (mm), the vertical axis indicates the image height (mm), and each graph indicates the wavelength of the incident light beam. As shown, it is known that the more the graphs are closer to the central vertical axis and the closer to each other, the better the correctability of the spherical aberration is. .

The second data of FIG. 3 shows astigmatism, the horizontal axis represents the focus (mm), the vertical axis represents the image height (mm), and the graph S represents the sagital, which is a light beam incident in the horizontal direction with the lens, A graph T represents a tangential, which is a light beam incident in a direction perpendicular to the lens. Here, it is known that the closer the graphs S and T are and the closer they are to the central vertical axis, the better the correctability of the astigmatism is.

The third data in FIG. 3 shows distortion aberration, the horizontal axis indicates the distortion (%) and the vertical axis indicates the image height (mm). It is judged that the optical distortion of the first embodiment according to the present invention is good at 2% or less.

<Second embodiment>

4 shows a second embodiment of a high-resolution wide-angle lens system according to the present invention.

As shown, the first lens L1, the stop stop, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 from the object along the optical axis. will be placed in the order of

Table 3 below shows numerical data of lenses constituting the optical system according to the second embodiment of the present invention.

Surface RDY (radius of curvature) THI (thickness) Nd (refractive index) Vd (Abesu) Object Infinity 400.00 One Infinity 0.00 2 1.40 0.66 1.5441 56.0 3 11.30 0.05 Stop 6.81 0.20 1.6500 21.5 5 2.50 0.20 6 Infinity 0.07 7 -77.15 0.38 1.5850 30.0 8 -7.28 0.56 9 10.54 0.35 1.6150 25.9 10 20.94 0.26 11 2.67 0.63 1.5850 30.0 12 1.42 0.19 13 Infinity 0.21 1.5168 64.2 14 Infinity 0.59 Image Infinity 0.00

As shown in FIG. 4 , the first lens L1, the stop stop, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 from the object side as shown in FIG. is arranged, and when the optical axis direction is set as X and the direction orthogonal to the optical axis is set as Y axis, the aspherical expression is the same as in Equation 1 above.

The aspherical surface is a curved surface obtained by rotating the curve obtained by the aspherical expression of Equation 1 about the optical axis, R is the radius of curvature, K is the conic constant, A ₃ , A ₄ , A ₅ , A ₆ ,..., A ₁₄ is the aspheric coefficient.

From Equation 1, aspheric coefficients having data of each of the above lenses are shown in Table 4 below.

s2 s3 s4 s5 s7 s8 s9 s10 s11 s12 K -1.E+00 -7.E+01 -3.E+01 3.E+00 -1.E+02 -5.E+01 -1.E+02 -1.E+02 -1.E+01 -5.E+00 A3 3.E-02 -3.E-01 -4.E-01 -2.E-01 -2.E-01 -1.E-01 7.E-02 -6.E-02 -3.E-01 -2.E-01 A4 2.E-02 1.E+00 2.E+00 6.E-01 1.E-01 1.E-01 -2.E-01 2.E-01 2.E-01 1.E-01 A5 7.E-02 -4.E+00 -4.E+00 2.E+00 -4.E-01 -2.E+00 2.E-01 -3.E-01 -9.E-02 -3.E-02 A6 -1.E+00 8.E+00 5.E+00 -2.E+01 2.E+00 8.E+00 4.E-01 2.E-01 1.E-02 4.E-03 A7 5.E+00 -2.E+01 -1.E+01 1.E+02 -4.E+00 -2.E+01 -1.E+00 -7.E-02 2.E-05 4.E-04 A8 -1.E+01 3.E+01 4.E+01 -2.E+02 3.E+00 3.E+01 2.E+00 1.E-02 -3.E-04 -2.E-04 A9 1.E+01 -4.E+01 -8.E+01 3.E+02 4.E+00 -2.E+01 -1.E+00 -1.E-03 5.E-05 3.E-05 A10 -9.E+00 2.E+01 8.E+01 -2.E+02 -8.E+00 8.E+00 4.E-01 -5.E-05 -3.E-06 -2.E-06 A11 2.E+00 -6.E+00 -3.E+01 6.E+01 3.E+00 -1.E+00 -5.E-02 1.E-05 7.E-08 4.E-08

Here, the dispersion constant V2 of the second lens L2, the dispersion constant V4 of the fourth lens L4, and the dispersion constant V5 of the fifth lens L5 satisfy V2+V3+V4+V5 = 107.4, and , the dispersion constant V2 of the second lens L2 and the dispersion constant V5 of the fifth lens L5 satisfy V2+V5 = 51.5, and the diameter of the entrance pupil of the lens system EPD and the image plane height ImagH are EPD/ ImagH = 0.508 is satisfied.

5 shows an aberration diagram according to a second embodiment of the present invention.

The first data in FIG. 5 shows spherical aberration, the horizontal axis indicates the focus (mm), the vertical axis indicates the image height (mm), and each graph indicates the wavelength of the incident light beam. As shown, it is known that the correctability of spherical aberration is good as the graphs are closer to the central vertical axis and closer to each other, and the spherical aberration of the second embodiment according to the present invention is considered to be good at 0.025 mm (focus) or less. .

The second data in FIG. 5 shows astigmatism, the horizontal axis represents the focus (mm), the vertical axis represents the image height (mm), and the graph S represents the sagital, which is a light beam incident in the horizontal direction with the lens, A graph T represents a tangential, which is a light beam incident in a direction perpendicular to the lens. Here, it is known that the closer the graphs S and T are and the closer they are to the central vertical axis, the better the correctability of the astigmatism is.

The third data in FIG. 5 shows distortion aberration, the horizontal axis indicates the distortion (%) and the vertical axis indicates the image height (mm). As the distortion aberration of the second embodiment according to the present invention, the optical distortion is judged to be good at 2% or less.

<Third embodiment>

6 shows a third embodiment of a high-resolution wide-angle lens system according to the present invention.

As shown, the first lens L1, the stop stop, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 from the object along the optical axis as shown. will be placed in the order of

Table 5 below shows numerical data of lenses constituting the optical system according to the third embodiment of the present invention.

Surface RDY (radius of curvature) THI (thickness) Nd (refractive index) Vd (Abesu) Object Infinity 400.00 One Infinity 0.00 2 1.35 0.68 1.5441 56.0 Stop 10.00 0.07 4 -41.06 0.20 1.6500 21.5 5 5.08 0.15 6 Infinity 0.14 7 -33.97 0.36 1.5850 30.0 8 -24.15 0.46 9 10.57 0.35 1.6150 25.9 10 30.80 0.28 11 2.45 0.65 1.5850 30.0 12 1.38 0.18 13 Infinity 0.21 1.5168 64.2 14 Infinity 0.58 Image Infinity 0.01

As shown in FIG. 6 , the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 and the fifth lens L5 are disposed from the object side. , when the optical axis direction is set to X and the direction orthogonal to the optical axis is set to the Y axis, the aspherical expression is the same as in Equation 1 above.

The aspherical surface is a curved surface obtained by rotating the curve obtained by the aspherical expression of Equation 1 about the optical axis, R is the radius of curvature, K is the conic constant, A ₃ , A ₄ , A ₅ , A ₆ ,..., A ₁₄ is the aspheric coefficient.

From Equation 1, aspheric coefficients having data of each of the above lenses are shown in Table 6 below.

s2 s3 s4 s5 s7 s8 s9 s10 s11 s12 K -1.E+00 -7.E+01 -3.E+01 3.E+01 1.E+02 5.E+01 -1.E+02 -1.E+02 -9.E+00 -6.E+00 A3 3.E-02 -1.E-01 -4.E-01 -3.E-01 -2.E-01 -2.E-01 -9.E-02 -2.E-01 -5.E-01 -1.E-01 A4 1.E-01 4.E-02 7.E+00 7.E+00 -2.E-03 2.E-02 4.E-01 4.E-01 3.E-01 -9.E-02 A5 -9.E-01 2.E+00 -8.E+01 -6.E+01 2.E-01 5.E-02 -1.E+00 -3.E-01 -1.E-01 1.E-01 A6 3.E+00 -1.E+01 4.E+02 3.E+02 -2.E+00 -5.E-01 3.E+00 6.E-02 3.E-02 -7.E-02 A7 -8.E+00 5.E+01 -2.E+03 -8.E+02 9.E+00 1.E+00 -4.E+00 6.E-02 -3.E-03 2.E-02 A8 1.E+01 -1.E+02 3.E+03 1.E+03 -3.E+01 -2.E+00 3.E+00 -5.E-02 2.E-04 -3.E-03 A9 -1.E+01 2.E+02 -4.E+03 -1.E+03 5.E+01 9.E-01 -2.E+00 2.E-02 7.E-06 3.E-04 A10 7.E+00 -1.E+02 3.E+03 6.E+02 -5.E+01 7.E-02 4.E-01 -2.E-03 -1.E-06 1.E-05 A11 -2.E+00 4.E+01 -7.E+02 -9.E+01 2.E+01 -2.E-01 -5.E-02 2.E-04 4.E-08 3.E-07

Here, the dispersion constant V2 of the second lens L2, the dispersion constant V4 of the fourth lens L4, and the dispersion constant V5 of the fifth lens L5 satisfy V2+V3+V4+V5 = 107.4, and , the dispersion constant V2 of the second lens L2 and the dispersion constant V5 of the fifth lens L5 satisfy V2+V5 = 51.5, and the diameter of the entrance pupil of the lens system EPD and the image plane height ImagH are EPD/ ImagH = 0.506 is satisfied.

7 shows an aberration diagram according to a third embodiment of the present invention.

The first data of FIG. 7 shows spherical aberration, and the horizontal axis indicates the focus (mm), the vertical axis indicates the image height (mm), and each graph indicates the wavelength of the incident light beam. As shown, it is known that the more the graphs are closer to the central vertical axis and the closer to each other, the better the correctability of the spherical aberration is. .

The second data of FIG. 7 shows astigmatism, the horizontal axis represents the focus (mm), the vertical axis represents the image height (mm), and the graph S represents the sagital, which is a light beam incident in the horizontal direction with the lens, A graph T represents a tangential, which is a light beam incident in a direction perpendicular to the lens. Here, it is known that the closer the graphs S and T are and the closer they are to the central vertical axis, the better the correctability of the astigmatism is.

The third data in FIG. 7 shows distortion aberration, the horizontal axis indicates the distortion (%) and the vertical axis indicates the image height (mm). The optical distortion as a distortion aberration of the third embodiment according to the invention is judged to be good at 2% or less.

<Fourth embodiment>

8 shows a fourth embodiment of a high-resolution wide-angle lens system according to the present invention.

As shown, the first lens L1, the stop stop, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 from the object along the optical axis as shown. will be placed in the order of

Table 7 below shows numerical data of lenses constituting the optical system according to the fourth embodiment of the present invention.

Surface RDY (radius of curvature) THI (thickness) Nd (refractive index) Vd (Abesu) Object Infinity 400.00 One Infinity 0.00 2 1.36 0.67 1.5441 56.0 Stop 9.06 0.07 4 -36.27 0.20 1.6500 21.5 5 6.09 0.15 6 Infinity 0.14 7 -19.12 0.34 1.5850 30.0 8 -34.55 0.45 9 5.68 0.35 1.6150 25.9 10 5.43 0.34 11 1.64 0.60 1.5850 30.0 12 1.19 0.21 13 Infinity 0.21 1.5168 64.2 14 Infinity 0.58 Image Infinity 0.01

As shown in FIG. 8 , the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 and the fifth lens L5 are disposed from the object side. , when the optical axis direction is set to X and the direction orthogonal to the optical axis is set to the Y axis, the aspherical expression is the same as in Equation 1 above.

The aspherical surface is a curved surface obtained by rotating the curve obtained by the aspherical expression of Equation 1 about the optical axis, R is the radius of curvature, K is the conic constant, A ₃ , A ₄ , A ₅ , A ₆ ,..., A ₁₄ is the aspheric coefficient.

From Equation 1, the aspheric coefficients having the data of each of the above lenses are shown in Table 8 below.

s2 s3 s4 s5 s7 s8 s9 s10 s11 s12 K -1.E+00 -7.E+01 -3.E+01 4.E+01 1.E+02 5.E+01 -5.E+01 -9.E+01 -2.E+00 -5.E+00 A3 3.E-02 -1.E-01 -5.E-01 -1.E-01 -2.E-01 -2.E-01 -9.E-02 -4.E-01 -6.E-01 -2.E-01 A4 3.E-01 4.E-02 1.E+01 4.E+00 3.E-01 4.E-01 -1.E-01 1.E+00 8.E-01 3.E-01 A5 -2.E+00 2.E+00 -1.E+02 -4.E+01 -3.E+00 -2.E+00 4.E+00 -3.E+00 -9.E-01 -3.E-01 A6 7.E+00 -1.E+01 6.E+02 2.E+02 2.E+01 7.E+00 -2.E+01 4.E+00 8.E-01 2.E-01 A7 -2.E+01 6.E+01 -2.E+03 -6.E+02 -9.E+01 -2.E+01 7.E+01 -4.E+00 -4.E-01 -9.E-02 A8 3.E+01 -1.E+02 4.E+03 1.E+03 2.E+02 3.E+01 -2.E+02 3.E+00 2.E-01 3.E-02 A9 -3.E+01 2.E+02 -5.E+03 -9.E+02 -3.E+02 -2.E+01 3.E+02 -2.E+00 -5.E-02 -9.E-03 A10 1.E+01 -2.E+02 3.E+03 4.E+02 3.E+02 1.E+01 -3.E+02 7.E-01 9.E-03 2.E-03 A11 -4.E+00 6.E+01 -1.E+03 -8.E+01 -1.E+02 -3.E+00 2.E+02 -2.E-01 -1.E-03 -3.E-04

Here, the dispersion constant V2 of the second lens L2, the dispersion constant V4 of the fourth lens L4, and the dispersion constant V5 of the fifth lens L5 satisfy V2+V3+V4+V5 = 107.4, and , the dispersion constant V2 of the second lens L2 and the dispersion constant V5 of the fifth lens L5 satisfy V2+V5 = 51.5, and the diameter of the entrance pupil of the lens system EPD and the image plane height ImagH are EPD/ ImagH = 0.506 is satisfied.

9 shows an aberration diagram according to a fourth embodiment of the present invention.

The first data of FIG. 9 shows spherical aberration, and the horizontal axis represents the focus (mm), the vertical axis represents the image height (mm), and each graph represents the wavelength of the incident light beam. As shown, it is known that the more the graphs are closer to the central vertical axis and the closer they are to each other, the better the correctability of the spherical aberration is. .

The second data of FIG. 9 shows astigmatism, the horizontal axis represents the focus (mm), the vertical axis represents the image height (mm), and the graph S represents the sagital, which is a light beam incident in the horizontal direction with the lens, A graph T represents a tangential, which is a light beam incident in a direction perpendicular to the lens. Here, it is known that the closer the graphs S and T are and the closer they are to the central vertical axis, the better the correctability of the astigmatism is.

The third data in FIG. 9 shows distortion aberration, the horizontal axis indicates the distortion (%) and the vertical axis indicates the image height (mm). The optical distortion as a distortion aberration of the fourth embodiment according to the invention is judged to be good at 2% or less.

L1: first lens L2: second lens
L3 : 3rd lens L4 : 4th lens
L5: 5th lens

Claims (3)

It includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in order from the object side, wherein the first lens has a convex object-side surface and has a positive refractive power, , the fifth lens has a concave image side surface, and all of the first to fifth lenses have an aspherical surface,
The dispersion constant V2 of the second lens, the dispersion constant V4 of the fourth lens, and the dispersion constant V5 of the fifth lens satisfy V2+V3+V4+V5 < 115,
A high-resolution lens system, characterized in that the entrance pupil diameter EPD and the image plane height ImagH satisfy 0.5 < EPD/ImagH < 1.0. The method of claim 1, wherein the dispersion constant V2 of the second lens and the dispersion constant V5 of the fifth lens are,
High-resolution lens system, characterized in that it satisfies V2+V5 < 60. delete

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