CN115728914B - Optical imaging lens - Google Patents

Abstract

The invention relates to the technical field of lenses. The invention discloses an optical imaging lens, which comprises six lenses, wherein a first lens is a convex-concave lens with negative refractive index, a second lens is a convex surface with negative refractive index and the object side surface is a concave surface at the paraxial region, a third lens, a fourth lens and a sixth lens are all convex-convex lenses with positive refractive index, a fifth lens is a concave surface with negative refractive index and the object side surface is a glass spherical lens, the second lens, the fourth lens, the fifth lens and the sixth lens are all plastic aspheric lenses, and the optical imaging lens meets the following conditions: r11 is <13.50mm and R11-R12 is <9.50mm. The invention has the advantages of short overall length of the lens, small volume and low cost; the angle of view is big, and imaging quality is good, and the temperature drift is little advantage.

Description

An optical imaging lens

Technical Field

The present invention belongs to the technical field of lenses, and in particular relates to an optical imaging lens.

Background technique

With the continuous advancement of science and technology and the continuous improvement of living standards, optical imaging lenses have also developed rapidly in recent years. Optical imaging lenses are widely used in various fields such as smart phones, tablets, vehicle-mounted monitoring, security monitoring, drone aerial photography, machine vision systems, video conferencing, etc. Therefore, the requirements for optical imaging lenses are getting higher and higher.

However, there are still many shortcomings in the optical imaging lenses currently on the market. For example, the total optical length (TTL) is too large and the number of lenses is too large, which makes the overall cost and weight of the lens too high and has limitations in installation and use. In order to improve the resolution and correct chromatic aberration, optical imaging lenses with a large field of view often use multiple pieces of glass or glued lenses, which have the disadvantages of being too costly and too large in size. The lens has a large temperature drift, and when the temperature disturbance is too large, it affects the imaging quality. Therefore, it is necessary to improve it to meet the increasing demands of consumers.

Summary of the invention

The object of the present invention is to provide an optical imaging lens to solve the above-mentioned technical problems.

To achieve the above object, the technical solution adopted by the present invention is: an optical imaging lens, comprising a first lens to a sixth lens in sequence along an optical axis from an object side to an image side; the first lens to the sixth lens each comprises an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing imaging light to pass through;

The first lens has a negative refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

The second lens has a negative refractive power, the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is concave;

The third lens has a positive refractive power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface;

The fourth lens element has a positive refractive power, the object side surface of the fourth lens element is a convex surface, and the image side surface of the fourth lens element is a convex surface;

The fifth lens element has a negative refractive power, and the object side surface of the fifth lens element is a concave surface;

The sixth lens element has a positive refractive power, the object side surface of the sixth lens element is a convex surface, and the image side surface of the sixth lens element is a convex surface;

The first lens and the third lens are both glass spherical lenses, and the second lens, the fourth lens, the fifth lens and the sixth lens are all plastic aspherical lenses;

The optical imaging lens has only the first to sixth lenses with refractive power;

The optical imaging lens satisfies: R11<13.50mm and R11-R12<9.50mm, wherein R11 and R12 are the curvature radii of the object side surface and the image side surface of the first lens, respectively.

Furthermore, the optical imaging lens also satisfies: -7.50mm<f1<-5.00mm, -3.00mm≤f2<-2.00mm, 3.00mm<f3<4.00mm, 2.00mm<f4<3.00mm, -3.00mm<f5<-1.00mm, 2.50mm<f6<3.50mm, wherein f1, f2, f3, f4, f5 and f6 are the focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens respectively.

Furthermore, the optical imaging lens also satisfies: 4.00<|f1/f|<6.00, 1.50<|f2/f|<3.00, 2.00<|f3/f|<3.00, 1.50<|f4/f|<2.50, 1.00<|f5/f|<2.00, 1.00<|f6/f|<3.00, wherein f is the overall focal length of the optical imaging lens, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, and f6 is the focal length of the sixth lens.

Furthermore, the optical imaging lens also satisfies the following requirements: 1.80<nd1<2.00, 20.00<vd1<50.00; 1.50<nd2<1.70, 50.00<vd2<60.00; 1.70<nd3<1.90, 19.00<vd3<30.00; 1.50<nd4<1.70, 50.00<vd4<70.00; 1.50<nd5<1.70, 15.00<vd5<25.00; 1.50<nd6<1.70, 50.00<vd6<60.00, wherein nd1-nd6 are the refractive indices of the first lens to the sixth lens respectively, and vd1-vd6 are the dispersion coefficients of the first lens to the sixth lens respectively.

Furthermore, the optical imaging lens also satisfies: 0.80<(CT4+CT5)/CT6<1.10, wherein CT4, CT5 and CT6 are the thicknesses of the fourth lens, the fifth lens and the sixth lens on the optical axis, respectively.

Furthermore, the optical imaging lens also satisfies: |f12/f3|<0.50, wherein f12 is the combined focal length of the first lens and the second lens, and f3 is the focal length of the third lens.

Furthermore, the optical imaging lens also satisfies: 5.00<│f45/f│<16.00, wherein f45 is the combined focal length of the fourth and fifth lenses, and f is the overall focal length of the optical imaging lens.

Furthermore, the second lens, the fourth lens, the fifth lens and the sixth lens are all high-order even-order aspheric lenses.

Furthermore, it also includes an aperture, which is arranged between the third lens and the fourth lens.

Furthermore, the optical imaging lens also satisfies: TTL＜17.00mm, wherein TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis.

Beneficial technical effects of the present invention:

The present invention adopts a combination design of two glass spherical lenses and four plastic aspherical lenses, and through corresponding design of each lens, the lens has the advantages of short overall length, small size, convenient installation and use, low cost; large field of view angle (greater than 195.0°), good imaging quality; small temperature drift, and can well maintain the working state at various temperatures.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the structure of Embodiment 1 of the present invention;

FIG2 is an MTF diagram of Example 1 of the present invention under visible light 435-650nm;

FIG3 is a defocus curve diagram of 60 lp/mm under visible light 435-650 nm in Example 1 of the present invention;

FIG4 is a lateral chromatic aberration curve diagram of Example 1 of the present invention under visible light 435nm-650nm;

FIG5 is a longitudinal chromatic aberration curve diagram of Example 1 of the present invention under visible light 435nm-650nm;

FIG6 is a graph showing field curvature and distortion curves of the first embodiment of the present invention under visible light of 435 nm-650 nm;

FIG7 is a schematic diagram of the structure of Embodiment 2 of the present invention;

FIG8 is an MTF diagram of Example 2 of the present invention under visible light 435-650nm;

FIG9 is a defocus curve diagram of 60 lp/mm under visible light 435-650 nm of Example 2 of the present invention;

FIG10 is a lateral chromatic aberration curve of Example 2 of the present invention under visible light 435nm-650nm;

FIG11 is a longitudinal chromatic aberration curve diagram of Example 2 of the present invention under visible light 435nm-650nm;

FIG12 is a graph showing field curvature and distortion curves of the second embodiment of the present invention under visible light of 435 nm-650 nm;

FIG13 is a schematic diagram of the structure of Embodiment 3 of the present invention;

FIG14 is an MTF diagram of Example 3 of the present invention under visible light 435-650nm;

FIG15 is a defocus curve diagram of 60 lp/mm under visible light 435-650 nm of Example 3 of the present invention;

FIG16 is a lateral chromatic aberration curve of Example 3 of the present invention under visible light 435nm-650nm;

FIG17 is a longitudinal chromatic aberration curve of Example 3 of the present invention under visible light 435nm-650nm;

FIG. 18 is a graph showing the field curvature and distortion curves of the third embodiment of the present invention under visible light of 435 nm-650 nm.

Detailed ways

To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

The term "a lens having a positive refractive power (or a negative refractive power)" means that the paraxial refractive power of the lens calculated by Gaussian optical theory is positive (or negative). The term "object side (or image side) of the lens" is defined as a specific range of the lens surface through which the imaging light passes. The concave and convex shape of the lens surface can be determined by the judgment method of the general knowledgeable person in this field, that is, the concave and convex shape of the lens surface can be determined by the positive and negative signs of the radius of curvature (abbreviated as R value). R value can be commonly used in optical design software, such as Zemax or CodeV. R value is also commonly found in the lens data sheet of optical design software. For the object side, when the R value is positive, the object side is determined to be convex; when the R value is negative, the object side is determined to be concave. Conversely, for the image side, when the R value is positive, the image side is determined to be concave; when the R value is negative, the image side is determined to be convex.

The present invention discloses an optical imaging lens, which comprises a first lens to a sixth lens in sequence along an optical axis from an object side to an image side; the first lens to the sixth lens each comprises an object side surface facing the object side and allowing imaging light to pass through, and an image side surface facing the image side and allowing imaging light to pass through.

The first lens has a negative refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface.

The second lens has a negative refractive power, the object side surface of the second lens is a convex surface near the optical axis, and the image side surface of the second lens is a concave surface.

The third lens element has a positive refractive power, the object side surface of the third lens element is a convex surface, and the image side surface of the third lens element is a convex surface.

The fourth lens element has a positive refractive power, the object side surface of the fourth lens element is a convex surface, and the image side surface of the fourth lens element is a convex surface.

The fifth lens element has a negative refractive power, and the object side surface of the fifth lens element is a concave surface.

The sixth lens element has a positive refractive power, the object side surface of the sixth lens element is a convex surface, and the image side surface of the sixth lens element is a convex surface.

The first lens and the third lens are both glass spherical lenses, and the second lens, the fourth lens, the fifth lens and the sixth lens are all plastic aspherical lenses, which are beneficial to correcting the secondary spectrum and higher-order aberrations, and correcting the temperature drift of the lens well, and can well ensure the working state under different temperature conditions.

The optical imaging lens has only the first to sixth lenses with refractive power.

The optical imaging lens satisfies: R11<13.50mm and R11-R12<9.50mm, wherein R11 and R12 are respectively the curvature radii of the object side and image side of the first lens, which can better ensure that the field of view angle of the optical imaging lens is greater than 195.0°, thereby improving the overall field of view range of the lens and improving practicality.

The present invention adopts a design combining two glass spherical lenses and four plastic aspherical lenses, and by designing each lens accordingly, the lens has the advantages of short overall length, small size, convenient installation and use, and low cost; the field of view angle is greater than 195.0°, which improves the overall field of view range of the lens and improves practicality; the imaging quality is good; the temperature drift is small, and the working state at various temperatures can be well maintained.

Preferably, the optical imaging lens further satisfies the following requirements: -7.50mm<f1<-5.00mm, -3.00mm≤f2<-2.00mm, 3.00mm<f3<4.00mm, 2.00mm<f4<3.00mm, -3.00mm<f5<-1.00mm, 2.50mm<f6<3.50mm, wherein f1, f2, f3, f4, f5 and f6 are respectively the focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens, so that the focal length of each lens is evenly and reasonably distributed, thereby further improving the imaging quality.

Preferably, the optical imaging lens further satisfies: 4.00<|f1/f|<6.00, 1.50<|f2/f|<3.00, 2.00<|f3/f|<3.00, 1.50<|f4/f|<2.50, 1.00<|f5/f|<2.00, 1.00<|f6/f|<3.00, wherein f is the overall focal length of the optical imaging lens, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, and f6 is the focal length of the sixth lens, so that the optical power distribution of each lens is uniform and reasonable, thereby further improving the imaging quality.

Preferably, the optical imaging lens further satisfies: 1.80<nd1<2.00, 20.00<vd1<50.00; 1.50<nd2<1.70, 50.00<vd2<60.00; 1.70<nd3<1.90, 19.00<vd3<30.00; 1.50<nd4<1.70, 50.00<vd4<70.00; 1.50<nd5<1.70, 15.00<vd5<25.00; 1 .50<nd6<1.70, 50.00<vd6<60.00, wherein nd1-nd6 are the refractive indices of the first lens to the sixth lens respectively, and vd1-vd6 are the dispersion coefficients of the first lens to the sixth lens respectively, which further optimizes chromatic aberration and image aberration and improves imaging quality; and the first lens and the third lens are both made of glass materials with high refractive index and low dispersion coefficient, which can better optimize the optical structure, and at the same time is beneficial to the lens structure design, reduces the total length of the lens, and reduces the lens cost.

Preferably, the optical imaging lens also satisfies: 0.80<(CT4+CT5)/CT6<1.10, wherein CT4, CT5 and CT6 are the thicknesses of the fourth lens, the fifth lens and the sixth lens on the optical axis, respectively. By reasonably allocating the center thicknesses of the rear three lenses, it is beneficial to achieve a miniaturized design of the lens; while adjusting the ratio between the lenses can better distribute the focal length of the rear group, which is beneficial to correcting the lens astigmatism.

Preferably, the optical imaging lens also satisfies: |f12/f3|<0.50, where f12 is the combined focal length of the first lens and the second lens, and f3 is the focal length of the third lens. This is beneficial for controlling the aberration of the lens, so that the optical system can achieve better imaging effects even under large angle conditions.

Preferably, the optical imaging lens also satisfies: 5.00<│f45/f│<16.00, wherein f45 is the combined focal length of the fourth and fifth lenses, and f is the overall focal length of the optical imaging lens. This is beneficial to the aberration correction of the optical system and improves the imaging resolution of the lens.

Preferably, the second lens, the fourth lens, the fifth lens and the sixth lens are all high-order even-order aspheric lenses, which further optimize chromatic aberration and aberration and improve imaging quality.

Preferably, an aperture is further included, and the aperture is arranged between the third lens and the fourth lens to further improve the overall performance.

Preferably, the optical imaging lens also satisfies: TTL＜17.00mm, wherein TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, which effectively reduces the volume of the lens.

Embodiment 1

As shown in FIG. 1 , an optical imaging lens includes, from the object side A1 to the image side A2, a first lens 1, a second lens 2, a third lens 3, an aperture 7, a fourth lens 4, a fifth lens 5, a sixth lens 6, a protective glass 8 and an imaging surface 9 in sequence along an optical axis I; the first lens 1 to the sixth lens 6 each include an object-side surface facing the object side A1 and allowing imaging light to pass through, and an image-side surface facing the image side A2 and allowing imaging light to pass through.

The first lens 1 has a negative refractive power, an object-side surface 11 of the first lens 1 is a convex surface, and an image-side surface 12 of the first lens 1 is a concave surface.

The second lens element 2 has a negative refractive power. The object-side surface 21 of the second lens element 2 is a convex surface near the optical axis, and the image-side surface 22 of the second lens element 2 is a concave surface.

The third lens element 3 has a positive refractive power, an object-side surface 31 of the third lens element 3 is a convex surface, and an image-side surface 32 of the third lens element 3 is a convex surface.

The fourth lens element 4 has a positive refractive power. The object-side surface 41 of the fourth lens element 4 is a convex surface. The image-side surface 42 of the fourth lens element 4 is a convex surface.

The fifth lens element 5 has a negative refractive power. The object-side surface 51 of the fifth lens element 5 is a concave surface. The image-side surface 52 of the fifth lens element 5 is a convex surface near the optical axis.

The sixth lens element 6 has a positive refractive power. The object-side surface 61 of the sixth lens element 6 is a convex surface, and the image-side surface 62 of the sixth lens element 6 is a convex surface.

The first lens 1 and the third lens 3 are both glass spherical lenses, and the second lens 2, the fourth lens 4, the fifth lens 5 and the sixth lens 6 are all plastic aspherical lenses.

In this specific embodiment, the aperture 7 is disposed between the third lens 3 and the fourth lens 4, but it is not limited thereto. In other embodiments, the aperture 7 may also be disposed at other appropriate positions.

The detailed optical data of this specific embodiment are shown in Table 1-1.

Table 1-1 Detailed optical data of Example 1

In this specific embodiment, the object side surface 21, the object side surface 41, the object side surface 51, the object side surface 61, the image side surface 22, the image side surface 42, the image side surface 52 and the image side surface 62 are defined according to the following aspheric curve formula:

in:

r is the distance from a point on the optical surface to the optical axis.

z is the vector height of the point along the optical axis.

c is the curvature of the surface.

K is the quadratic constant of the surface.

A ₄ , A ₆ , A ₈ , A ₁₀ , A ₁₂ , A ₁₄ , and A ₁₆ are respectively the aspheric coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order.

Please refer to the following table for detailed parameter data of each aspheric surface:

Surface number K A _{4 A6 A8} A ₁₀ A ₁₂ A ₁₄ A ₁₆ twenty one 78.33 -1.650E-02 5.925E-03 -1.772E-03 3.351E-04 -3.792E-05 2.349E-06 -6.156E-08 twenty two -0.99 -2.404E-02 1.772E-02 -9.635E-03 2.685E-03 -3.394E-04 1.183E-05 3.815E-07 41 2.47 -1.777E-02 2.032E-03 -5.324E-02 7.036E-02 -2.889E-02 -2.810E-02 1.880E-02 42 -1.15 -9.155E-03 -4.762E-02 -3.262E-02 3.476E-02 3.987E-02 -5.153E-02 1.452E-02 51 -0.43 3.154E-01 -2.718E-01 1.019E-01 6.137E-02 -4.897E-02 -3.898E-04 5.132E-03 52 -233.96 8.392E-02 -2.882E-02 1.914E-03 5.191E-03 -1.939E-03 -2.836E-06 6.257E-05 61 -14.88 4.532E-03 -4.896E-03 2.117E-03 1.714E-05 -1.251E-04 2.333E-05 -1.381E-06 62 -0.82 1.521E-03 -1.727E-03 1.522E-03 -4.971E-04 8.353E-05 -7.857E-06 7.061E-07

Please refer to Table 4 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF curve diagram of this specific embodiment is shown in Figure 2. It can be seen that under the condition of 84lp/mm, it is greater than 0.4 in the entire field of view, with high resolution and good imaging quality; the defocus curve diagram is shown in Figure 3, the lateral chromatic aberration diagram is shown in Figure 4, and the longitudinal chromatic aberration diagram is shown in Figure 5. It can be seen that both chromatic aberration and aberration are well corrected, and the imaging quality is high; the field curvature and distortion diagrams are shown in (A) and (B) of Figure 6. It can be seen that both field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=1.336 mm; the field of view angle FOV=196.0°; the aperture value FNO=2.0; and the distance TTL from the object side surface 11 of the first lens 1 to the imaging surface 9 on the optical axis I is 16.388 mm.

This embodiment can well maintain the working state at various temperatures.

Embodiment 2

As shown in FIG. 7 , the surface profiles and refractive powers of the lenses of this embodiment and the first embodiment are substantially the same, except that the image side surface 52 of the fifth lens 5 is concave near the optical axis. In addition, the optical parameters such as the curvature radius of each lens surface and the lens thickness are also different.

The detailed optical data of this specific embodiment are shown in Table 2-1.

Table 2-1 Detailed optical data of Example 2

surface Diameter size/mm Curvature radius/mm Thickness/interval/mm Material Refractive Index Dispersion coefficient Focal length/mm - Infinity Infinity 11 First lens 11.927 12.123 1.099 Glass 1.91 31.32 -5.800 12 6.457 3.515 2.069 twenty one Second lens 6.230 9.801 1.009 plastic 1.54 55.98 -3.000 twenty two 3.808 1.340 1.854 31 The third lens 6.000 3.825 3.185 Glass 1.77 26.61 3.878 32 6.000 -8.539 0.131 7 Aperture 1.934 Infinity 0.134 41 The fourth lens 2.256 3.640 1.300 plastic 1.55 56.00 2.226 42 2.611 -1.596 0.081 51 Fifth lens 2.576 -2.001 0.541 plastic 1.67 20.38 -1.479 52 3.068 2.158 0.177 61 The sixth lens 3.501 2.802 2.062 plastic 1.54 55.71 2.683 62 4.299 -2.206 1.489 8 Protective glass 5.294 Infinity 0.700 Glass 1.52 64.20 Infinity - 5.485 Infinity 0.203 9 Imaging surface 5.613 Infinity 0.000

Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

Surface number K A _{4 A6 A8} A ₁₀ A ₁₂ A ₁₄ A ₁₆ twenty one -20.57 3.816E-04 2.239E-03 -1.583E-03 3.781E-04 -4.520E-05 2.748E-06 -6.764E-08 twenty two -0.81 -1.707E-02 2.189E-02 -1.192E-02 -1.209E-03 2.704E-03 -7.839E-04 7.398E-05 41 0.02 -6.955E-03 2.687E-02 -5.071E-02 3.403E-02 -2.261E-03 -1.248E-02 3.788E-03 42 -8.04 -6.326E-02 1.862E-02 -2.290E-02 -2.641E-02 3.590E-02 -1.452E-02 2.104E-03 51 1.05 3.922E-02 -8.584E-03 -3.752E-02 3.375E-02 -1.291E-02 5.343E-03 -2.300E-04 52 -19.03 1.716E-02 -2.714E-03 -5.237E-03 4.515E-03 -9.707E-04 -7.823E-05 4.661E-05 61 -26.25 2.608E-02 -1.206E-02 1.332E-03 6.794E-04 -2.917E-04 2.437E-05 3.472E-06 62 -0.54 2.404E-02 -1.972E-03 1.233E-04 3.445E-05 -1.948E-05 1.246E-06 -7.934E-09

Please refer to Table 4 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF curve diagram of this specific embodiment is shown in Figure 8. It can be seen that under the condition of 84lp/mm, it is greater than 0.5 in the entire field of view, with high resolution and good imaging quality; the defocus curve diagram is shown in Figure 9, the lateral chromatic aberration diagram is shown in Figure 10, and the longitudinal chromatic aberration diagram is shown in Figure 11. It can be seen that both chromatic aberration and aberration are well corrected, and the imaging quality is high; the field curvature and distortion diagrams are shown in (A) and (B) of Figure 12. It can be seen that both field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=1.348 mm; the field of view angle FOV=195.6°; the aperture value FNO=2.0; and the distance TTL from the object side surface 11 of the first lens 1 to the imaging surface 9 on the optical axis I is 16.033 mm.

This embodiment can well maintain the working state at various temperatures.

Embodiment 3

As shown in FIG. 13 , the surface profiles and refractive powers of the lenses of this embodiment and the first embodiment are substantially the same, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

The detailed optical data of this specific embodiment are shown in Table 3-1.

Table 3-1 Detailed optical data of Example 3

surface Diameter size/mm Curvature radius/mm Thickness/interval/mm Material Refractive Index Dispersion coefficient Focal length/mm - Infinity Infinity 11 First lens 14.082 13.405 1.195 Glass 1.92 35.28 -6.887 12 7.803 4.105 3.125 twenty one Second lens 6.628 20.891 1.065 plastic 1.54 55.98 -2.563 twenty two 4.207 1.272 1.091 31 The third lens 6.000 3.708 3.050 Glass 1.85 23.78 3.638 32 6.000 -11.815 0.397 7 Aperture 1.779 Infinity -0.008 41 The fourth lens 2.151 3.240 1.361 plastic 1.55 56.00 2.384 42 2.581 -1.854 0.120 51 Fifth lens 2.542 -1.132 0.507 plastic 1.67 20.38 -1.950 52 3.116 -10.290 0.100 61 The sixth lens 4.348 2.364 2.163 plastic 1.55 56.00 2.875 62 4.708 -3.168 1.436 8 Protective glass 5.549 Infinity 0.700 Glass 1.52 64.20 Infinity - 5.734 Infinity 0.203 9 Imaging surface 5.680 Infinity 0.000

Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

Surface number K A _{4 A6 A8} A ₁₀ A ₁₂ A ₁₄ A ₁₆ twenty one 37.16 -1.386E-02 5.627E-03 -1.712E-03 3.044E-04 -3.171E-05 1.801E-06 -4.332E-08 twenty two -0.89 -2.183E-02 1.863E-02 -1.050E-02 2.600E-03 -2.901E-04 1.697E-05 -1.233E-06 41 2.03 -1.933E-02 2.853E-02 -8.797E-02 9.735E-02 -1.949E-02 -5.569E-02 2.827E-02 42 -2.51 3.451E-03 -8.067E-02 -1.386E-02 2.320E-02 3.999E-02 -5.311E-02 1.636E-02 51 -0.59 3.116E-01 -2.991E-01 9.994E-02 6.918E-02 -5.716E-02 -9.090E-03 1.182E-02 52 -93.15 9.569E-02 -3.575E-02 1.908E-03 6.004E-03 -2.142E-03 -1.132E-04 1.143E-04 61 -20.16 2.039E-02 -7.477E-03 1.610E-03 8.118E-05 -1.178E-04 2.444E-05 -1.715E-06 62 -0.77 -2.522E-04 1.233E-03 8.673E-04 -4.288E-04 8.953E-05 -1.048E-05 6.587E-07

Please refer to Table 4 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF curve diagram of this specific embodiment is shown in Figure 14. It can be seen that under the condition of 84lp/mm, it is greater than 0.5 in the entire field of view, with high resolution and good imaging quality; the defocus curve diagram is shown in Figure 15, the lateral chromatic aberration diagram is shown in Figure 16, and the longitudinal chromatic aberration diagram is shown in Figure 11. It can be seen that both chromatic aberration and aberration are well corrected, and the imaging quality is high; the field curvature and distortion diagrams are shown in (A) and (B) of Figure 18. It can be seen that both field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=1.343 mm; the field of view angle FOV=195.9°; the aperture value FNO=2.0; and the distance TTL from the object side surface 11 of the first lens 1 to the imaging surface 9 on the optical axis I is 16.503 mm.

This embodiment can well maintain the working state at various temperatures.

Table 4 Values of important parameters of three embodiments of the present invention

Embodiment 1 Embodiment 2 Embodiment 3 f1 -6.887 -5.800 -6.887 f2 -2.575 -3.000 -2.563 f3 3.657 3.878 3.638 f4 2.393 2.226 2.384 f5 -2.309 -1.479 -1.950 f6 3.299 2.683 2.875 f 1.336 1.348 1.343 |f1/f| 5.155 4.302 5.128 |f2/f| 1.927 2.226 1.909 |f3/f| 2.737 2.877 2.709 |f4/f| 1.791 1.651 1.775 |f5/f| 1.729 1.097 1.452 |f6/f| 2.469 1.991 2.141 (CT4+CT5)/CT6 0.977 0.892 0.8635 │f12/f3│ 0.375 0.394 0.372 │f45/f│ 15.353 10.337 12.056 R11-R12 8.617 8.608 9.299

Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims (8)

1. An optical imaging lens, comprising a first lens to a sixth lens in order from the object side to the image side along an optical axis; each of the first lens to the sixth lens comprises an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing imaging light to pass through; characterized in that: The first lens has a negative refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; The second lens has a negative refractive power, the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is concave; The third lens has a positive refractive power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; The fourth lens element has a positive refractive power, the object side surface of the fourth lens element is a convex surface, and the image side surface of the fourth lens element is a convex surface; The fifth lens element has a negative refractive power, and the object side surface of the fifth lens element is a concave surface; The sixth lens element has a positive refractive power, the object side surface of the sixth lens element is a convex surface, and the image side surface of the sixth lens element is a convex surface; The first lens and the third lens are both glass spherical lenses, and the second lens, the fourth lens, the fifth lens and the sixth lens are all plastic aspherical lenses; The optical imaging lens has only the first to sixth lenses with refractive power; The optical imaging lens satisfies the following conditions: R11<13.50mm, R11-R12<9.50mm, 4.00<|f1/f|<6.00, 1.50<|f2/f|<3.00, 2.00<|f3/f|<3.00, 1.50<|f4/f|<2.50, 1.00<|f5/f|<2.00, 1.00<|f6/f|<3.00, |f12/f3|<0.50, wherein R11 and R12 are respectively the radii of curvature of the object side surface and the image side surface of the first lens, f is the overall focal length of the optical imaging lens, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, and f12 is the combined focal length of the first lens and the second lens. 2. The optical imaging lens according to claim 1, characterized in that the optical imaging lens also satisfies: -7.50mm<f1<-5.00mm, -3.00mm≤f2<-2.00mm, 3.00mm<f3<4.00mm, 2.00mm<f4<3.00mm, -3.00mm<f5<-1.00mm, 2.50mm<f6<3.50mm. 3. The optical imaging lens according to claim 1, characterized in that the optical imaging lens further satisfies the following conditions: 1.80<nd1<2.00, 20.00<vd1<50.00; 1.50<nd2<1.70, 50.00<vd2<60.00; 1.70<nd3<1.90, 19.00<vd3<30.00; 1.50<nd4<1.70, 50.00<vd4<70.00; 1.50<nd5<1.70, 15.00<vd5<25.00; 1.50<nd6<1.70, 50.00<vd6<60.00, wherein nd1-nd6 are the refractive indices of the first lens to the sixth lens respectively, and vd1-vd6 are the dispersion coefficients of the first lens to the sixth lens respectively. 4. The optical imaging lens according to claim 1, characterized in that the optical imaging lens also satisfies: 0.80<(CT4+CT5)/CT6<1.10, wherein CT4, CT5 and CT6 are thicknesses of the fourth lens, the fifth lens and the sixth lens on the optical axis, respectively. 5. The optical imaging lens according to claim 1, characterized in that the optical imaging lens further satisfies: 5.00<│f45/f│<16.00, wherein f45 is the combined focal length of the fourth and fifth lenses. 6 . The optical imaging lens according to claim 1 , wherein the second lens, the fourth lens, the fifth lens and the sixth lens are all high-order even-order aspheric lenses. 7. The optical imaging lens according to claim 1, further comprising an aperture, wherein the aperture is disposed between the third lens element and the fourth lens element. 8. The optical imaging lens according to claim 1, characterized in that the optical imaging lens also satisfies: TTL＜17.00mm, wherein TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis.