Optical lens

Abstract

The utility model relates to an optical lens which is arranged along an optical axis from an object side to an image side. The utility model discloses a multi-lens zoom lens, which sequentially comprises eight lenses in total, namely a first lens with negative focal power, a second lens with positive focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with positive focal power and an eighth lens with negative focal power, the first lens is a convex-concave lens; the image side surface of the second lens is a convex surface; the third lens is a convex-concave lens; and the eighth lens is a convex-concave lens. The optical lens provided by the utility model at least has one of the characteristics of ultra-large aperture, long focal length, low cost, small volume, no virtual focus in a temperature range of-40 DEG C to 80 DEG C and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of imaging lenses, and in particular to an optical lens with one of the characteristics of long focal length, small size, low cost, large aperture, large target surface, and no defocusing during the high and low temperature process of -40 to 80 °C. Background Art

[0002] In recent years, with the continuous improvement of people's safety awareness, surveillance lenses, as the "eyes" of humans, have played an increasingly important role in machine vision, artificial intelligence, criminal investigation surveillance, driverless driving, etc., which has promoted the development of the security surveillance field.

[0003] At the same time, with the popularization of security surveillance, the market has higher and higher requirements for the specifications of various surveillance lenses. The volume of the lens often increases continuously with the increase of the size of the imaging chip. The lenses with long focal lengths of the current mainstream chips generally have the characteristics of large volume and heavy weight, which are difficult to meet the requirements of product development.

[0004] The optical lenses on the current market still have the following deficiencies:

[0005] 1. The existing optical lenses cannot meet the requirements of the mainstream large target surface;

[0006] 2. The existing optical lenses cannot achieve the requirements of large aperture, short overall length, and low cost;

[0007] 3. They cannot be used in various complex climate environments.

[0008] Therefore, designing an optical lens with one of the characteristics of long focal length, small size, low cost, large aperture, large target surface, etc. has become the market development trend. Summary of the Utility Model

[0009] To solve the problems existing in the above-mentioned prior art, the purpose of the utility model is to provide an optical lens with one of the characteristics of super large aperture FNO≤1.0, long focal length f≥7.5mm, large target surface H≥8.8mm, low cost, small volume, and no defocusing in the temperature range of -40 °C to 80 °C.

[0010] To achieve the above-mentioned utility model purpose, the utility model provides an optical lens, which sequentially includes, along the direction from the object side to the image side of the optical axis: a first lens with negative optical power, a second lens with positive optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with positive optical power, and an eighth lens with negative optical power.

[0011] The first lens is a convex-concave lens;

[0012] The image side surface of the second lens is a convex surface.

[0013] The third lens is a convex-concave lens;

[0014] The eighth lens is a convex-concave lens;

[0015] The effective focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy the following relationship: -5.8 ≤ f8 / f ≤ -1.2;

[0016] The effective focal length f of the optical lens, the overall optical length TTL and the full image height H corresponding to the maximum field of view angle satisfy the following relationship: 2.9 ≤ f*H / TTL ≤ 4.

[0017] According to a technical solution of the present invention, the image side of the fourth lens is convex;

[0018] The object side of the fifth lens is convex;

[0019] The object side of the sixth lens is concave;

[0020] The seventh lens is a convex-convex lens.

[0021] According to a technical solution of the present invention, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy the following relationship: -2.4 ≤ f1 / f ≤ -1.7.

[0022] According to a technical solution of the present invention, the effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy the following relationship: 3 ≤ f2 / f ≤ 7.5.

[0023] According to a technical solution of the present invention, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy the following relationship: -4.6 ≤ f3 / f ≤ -2.65.

[0024] According to a technical solution of the present invention, the effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy the following relationship: 1.5 ≤ f4 / f ≤ 1.8.

[0025] According to a technical solution of the present invention, the effective focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy the following relationship: 1.1 ≤ f5 / f ≤ 1.46.

[0026] According to a technical solution of the present invention, the effective focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy the following relationship: -1.4 ≤ f6 / f ≤ -0.95.

[0027] According to a technical solution of the present utility model, the effective focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy the following relationship: 0.68 ≤ f7 / f ≤ 1.2.

[0028] According to a technical solution of the present utility model, the radius of curvature R31 of the object side surface and the radius of curvature R32 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy the following relationship: 1.3 ≤ (R31 + R32) / f ≤ 1.55.

[0029] According to a technical solution of the present utility model, the radius of curvature R81 of the object side surface and the radius of curvature R82 of the image side surface of the eighth lens and the effective focal length f of the optical lens satisfy the following relationship: 0.88 ≤ (R81 + R82) / f ≤ 1.17.

[0030] According to a technical solution of the present utility model, the air gap CT34 between the third lens and the fourth lens and the overall optical length TTL of the optical lens satisfy the following relationship: 0.025 ≤ CT34 / TTL ≤ 0.05.

[0031] According to a technical solution of the present utility model, the back focal length BFL of the optical lens and the overall optical length TTL satisfy the following relationship: 0.18 ≤ BFL / TTL ≤ 0.25.

[0032] According to a technical solution of the present utility model, the effective focal length fa of the front lens group of the optical lens and the effective focal length f satisfy the following relationship: -1.85 ≤ fa / f ≤ -1.4.

[0033] According to a technical solution of the present utility model, the effective focal length fb of the rear lens group of the optical lens and the effective focal length f satisfy the following relationship: 0.68 ≤ fb / f ≤ 0.88.

[0034] According to a technical solution of the present utility model, the effective focal length fa of the front lens group of the optical lens and the effective focal length fb of the rear lens group satisfy the following relationship: -2.2 ≤ fa / fb ≤ -1.74.

[0035] According to the solution of the present utility model, by providing that the optical lens includes eight lenses, and setting the optical powers of the first lens to the eighth lens to be negative optical power, positive optical power, negative optical power, positive optical power, positive optical power, negative optical power, positive optical power, and negative optical power respectively, an optical lens is obtained which has at least one of the characteristics of an ultra-large aperture FNO ≤ 1.0, a long focal length f ≥ 7.5 mm, low cost, small size, large target surface (capable of matching a chip larger than 1 / 1.8" inch), no defocusing in the temperature range of -40°C to 80°C, etc. The chief ray angle of incidence CRA of the lens < 15°, and it can be adapted to most current mainstream chips.

[0036] By reasonably allocating the effective focal length of the eighth lens L8, it is beneficial to control the trend of light, enabling the light to be transmitted smoothly to the image plane, matching the chip size, meeting the requirements of a large target surface of the lens, reducing the tolerance sensitivity of the eighth lens L8, and also being conducive to improving the relative illumination of the system.

[0037] By reasonably setting the effective focal length, total holographic height, and total optical length of the optical lens, the requirement of accommodating the monitoring perspectives corresponding to different chips can be met. When the total holographic height and effective focal length are determined, by reasonably controlling the total optical length of the optical lens, the optical lens can have a smaller size, thus achieving miniaturization. Brief Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a schematic structural diagram of the optical lens of the first embodiment in the present invention;

[0040] Figure 2 It is a schematic diagram of the F-Tan(theta) distortion of the optical lens of the first embodiment in the present invention;

[0041] Figure 3 It is a schematic structural diagram of the optical lens of the second embodiment in the present invention;

[0042] Figure 4 It is a schematic diagram of the F-Tan(theta) distortion of the optical lens of the second embodiment in the present invention;

[0043] Figure 5 It is a schematic structural diagram of the optical lens of the third embodiment in the present invention;

[0044] Figure 6 It is a schematic diagram of the F-Tan(theta) distortion of the optical lens of the third embodiment in the present invention;

[0045] Figure 7 It is a schematic structural diagram of the optical lens of the fourth embodiment in the present invention;

[0046] Figure 8 It is a schematic diagram of the F-Tan(theta) distortion of the optical lens of the fourth embodiment in the present invention. Detailed Embodiments

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0048] When describing the embodiments of the present invention, the orientation or positional relationships expressed by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" are based on the orientation or positional relationships shown in the relevant drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting the present invention.

[0049] In this article, the surface of each lens closest to the object is called the object side of the lens, and the surface of each lens closest to the imaging side is called the image side of the lens.

[0050] The following will describe the present invention in detail with reference to the drawings and specific embodiments. The embodiments cannot be described in detail one by one here, but the embodiments of the present invention are not limited to the following embodiments.

[0051] As Figures 1 to 8 shown, an embodiment of the present invention provides an optical lens, which sequentially includes: a first lens L1, a diaphragm STO, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a protective flat glass CG along the direction of the optical axis from the object side to the image side. Among them, the first lens L1, the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all aspherical lenses, and the fourth lens L4 is a spherical lens.

[0052] The materials of each lens are adopted in a glass-plastic hybrid manner, which is beneficial to reducing the cost of the optical system, and at the same time is beneficial to balancing the high and low temperature performance of the optical lens, achieving no defocus within the range of -40°C to +80°C while maintaining high imaging quality; at the same time, using glass lenses is beneficial to correcting the chromatic aberration of the optical system and improving the color saturation of the lens.

[0053] For the optical lens of the present invention, the first lens L1, the second lens L2, and the third lens L3 are the front lens group, and the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are the rear lens group.

[0054] The first lens L1 is a convex-concave lens with a negative optical power, which is beneficial to reducing the light angle of a large field of view, decreasing the incident angle of the light rays of the rear lens group, and facilitating the achievement of a larger aperture and smaller aberration.

[0055] The second lens L2 has a positive optical power and forms a combination of negative and positive optical powers with the first lens L1, which is beneficial to correcting aberrations such as chromatic aberration and field curvature; moreover, the image side of the second lens L2 is convex and has an obvious aspherical shape, which is more conducive to the smooth transition of light rays to the rear lens group, facilitating the achievement of a larger aperture and effectively reducing the generation of aberrations.

[0056] The third lens L3 is a convex-concave lens with a negative optical power, which is beneficial to reducing the light height and the light passing aperture of the rear lens group.

[0057] The image side of the fourth lens L4 is convex, it has a positive optical power, and the fourth lens L4 uses a glass material. Utilizing the high refractive index of the glass material is beneficial to correcting aberrations while making the lens thickness thinner, which is conducive to the miniaturization of the lens.

[0058] The object side of the fifth lens L5 is convex, it has a positive optical power, and an aspherical surface type is used, which can effectively converge the overall light rays, further correct the aberrations in the central field of view area, and is more conducive to the achievement of a large aperture at the same time.

[0059] The object side of the sixth lens L6 is concave, it has a negative optical power, and an aspherical surface type is used, which can effectively raise the light rays in the outer field of view and is beneficial to the achievement of a large target surface.

[0060] The seventh lens L7 is a convex-convex lens with a positive optical power, which can control the trend of light rays, converge the light rays, enabling the light rays entering the optical lens to be better transmitted and thus focused on the image plane, reducing the aberrations of the system and improving the imaging quality.

[0061] The eighth lens L8 is a convex-concave lens with a negative optical power, which can effectively correct the aberrations in the outer field of view of the system and is beneficial to improving the relative illumination at the same time.

[0062] In some embodiments of the present utility model, the effective focal length f8 of the eighth lens L8 and the effective focal length f of the optical lens satisfy the following relationship: -5.8 ≤ f8 / f ≤ -1.2; by reasonably allocating the effective focal length of the eighth lens L8, it is beneficial to controlling the trend of light rays, enabling the light rays to be smoothly transmitted to the image plane, being able to match the chip size, achieving the requirements of a large target surface of the lens, and also being able to reduce the tolerance sensitivity of the eighth lens L8, and is beneficial to improving the relative illumination of the system at the same time.

[0063] In some embodiments of the present utility model, the effective focal length f of the optical lens, the total optical length TTL, and the full image height H corresponding to the maximum field of view satisfy the following relationship: 2.9 ≤ f * H / TTL ≤ 4; by reasonably setting the effective focal length, image height, and total optical length of the optical lens, the requirement of accommodating the monitoring perspectives corresponding to different chips can be met. When the full image height and the effective focal length are determined, by reasonably controlling the total optical length of the optical lens, the optical lens can have a smaller size, thereby achieving miniaturization.

[0064] In some embodiments of the present utility model, the effective focal length f1 of the first lens L1 and the effective focal length f of the optical lens satisfy the following relationship: -2.4 ≤ f1 / f ≤ -1.7; by reasonably configuring the effective focal length of the first lens L1, it is beneficial for the optical lens to capture more light with a large field of view, thereby increasing the field of view, achieving a field of view FOV ≥ 63°, and improving the relative illumination of the optical lens.

[0065] In some embodiments of the present utility model, the effective focal length f2 of the second lens L2 and the effective focal length f of the optical lens satisfy the following relationship: 3 ≤ f2 / f ≤ 7.5; by reasonably configuring the optical power of the second lens L2, it is beneficial for the smooth transition of large-angle light, and at the same time, it can effectively raise the light in the outer field of view, which is beneficial for achieving a large target surface; at the same time, it can also avoid the problem of defocus during the high and low temperature processes of the optical lens and ensure the imaging quality.

[0066] In some embodiments of the present utility model, the effective focal length f3 of the third lens L3 and the effective focal length f of the optical lens satisfy the following relationship: -4.6 ≤ f3 / f ≤ -2.65; by reasonably distributing the effective focal length of the third lens L3, it is beneficial to control the trend of light, make the light entering the optical system transition smoothly, and is beneficial to reducing the tolerance sensitivity of the third lens L3 and improving the production yield of the product.

[0067] In some embodiments of the present utility model, the effective focal length f4 of the fourth lens L4 and the effective focal length f of the optical lens satisfy the following relationship: 1.5 ≤ f4 / f ≤ 1.8; by reasonably distributing the effective focal length of the fourth lens L4, the trend of light can be effectively controlled, the light can be converged, the trend of light with a large field of view can be further reduced, which is beneficial for correcting aberration, and at the same time, the thickness of the fourth lens L4 can be made thinner, so that the optical lens has a smaller size, thereby achieving miniaturization.

[0068] In some embodiments of the present utility model, the effective focal length f5 of the fifth lens L5 and the effective focal length f of the optical lens satisfy the following relationship: 1.1 ≤ f5 / f ≤ 1.46; by reasonably distributing the effective focal length of the fifth lens L5, the light entering the optical system is compressed and converged, effectively reducing the light passing aperture of the rear group of lenses, which is beneficial for achieving a large aperture FNO ≤ 1.0.

[0069] In some embodiments of the present utility model, the effective focal length f6 of the sixth lens L6 and the effective focal length f of the optical lens satisfy the following relationship: -1.4 ≤ f6 / f ≤ -0.95; by reasonably allocating the effective focal length of the sixth lens L6, it is beneficial to correct the spherical aberration of the system, improve the imaging quality, and at the same time facilitate the realization of no defocus at high and low temperatures for the system.

[0070] In some embodiments of the present utility model, the effective focal length f7 of the seventh lens L7 and the effective focal length f of the optical lens satisfy the following relationship: 0.68 ≤ f7 / f ≤ 1.2; by reasonably allocating the effective focal length of the seventh lens L7, it is beneficial to control the light path, converge the light, contribute to better light transmission, reduce the aberration of the optical lens, and effectively weaken the ghost image of the optical lens, thereby improving the imaging quality of the lens.

[0071] In some embodiments of the present utility model, the radius of curvature R31 of the object side and the radius of curvature R32 of the image side of the third lens L3 and the effective focal length f of the optical lens satisfy the following relationship: 1.3 ≤ (R31 + R32) / f ≤ 1.55; by reasonably controlling the ratio relationship between the sum of the radius of curvature of the object side and the image side of the third lens L3 and the effective focal length, it is beneficial to reduce the tolerance sensitivity of the third lens L3 and improve the production yield of the product.

[0072] In some embodiments of the present utility model, the radius of curvature R81 of the object side and the radius of curvature R82 of the image side of the eighth lens L8 and the effective focal length f of the optical lens satisfy the following relationship: 0.88 ≤ (R81 + R82) / f ≤ 1.17; by reasonably controlling the ratio relationship between the sum of the radius of curvature of the object side and the image side of the eighth lens L8 and the effective focal length, it is beneficial to control the light path and weaken the ghost image of the system.

[0073] In some embodiments of the present utility model, the air gap CT34 between the third lens L3 and the fourth lens L4 and the total optical length TTL of the optical lens satisfy the following relationship: 0.025 ≤ CT34 / TTL ≤ 0.05, which is beneficial for the smooth transition of light, beneficial to reducing the tolerance sensitivity of the lens, and improving the production yield of the product.

[0074] In some embodiments of the present utility model, the back focal length BFL of the optical lens and the total optical length TTL of the optical lens satisfy the following relationship: 0.18 ≤ BFL / TTL ≤ 0.25; on the basis of realizing miniaturization, by controlling the back focal length of the optical system, the optical lens has the characteristic of a long back focal length, which can reserve installation space for optical components, facilitate the assembly of the optical lens, avoid interference, and ensure the stability and reliability of the production of the optical lens.

[0075] In some embodiments of the present utility model, the effective focal length fa of the front lens group of the optical lens and the effective focal length f satisfy the following relationship: -1.85 ≤ fa / f ≤ -1.4; by reasonably distributing the effective focal length of the front lens group, it is beneficial to reduce the tolerance sensitivity of the optical lens.

[0076] In some embodiments of the present utility model, the effective focal length fb of the rear lens group of the optical lens and the effective focal length f satisfy the following relationship: 0.68 ≤ fb / f ≤ 0.88; by reasonably distributing the effective focal length of the rear lens group, it is beneficial to make the optical total length of the optical lens shorter.

[0077] In some embodiments of the present utility model, the effective focal length fa of the front lens group of the optical lens and the effective focal length fb of the rear lens group satisfy the following relationship: -2.2 ≤ fa / fb ≤ -1.74; on the basis of realizing miniaturization, by controlling the ratio of the front and rear group focal lengths of the optical system, the optical lens has the characteristic of long back focus, which is beneficial to the assembly of the optical lens.

[0078] Four specific embodiments are given below according to the above settings of the present utility model to specifically illustrate the optical lens according to the present utility model. The optical lens according to the present utility model has a total of eight lenses. Each cemented surface of the cemented lens is denoted as one surface. Together with the object surface OBJ, the aperture stop STO, the cover glass CG, and the image surface IMA, there are a total of 21 surfaces. Among them, the aperture stop STO is disposed between the first lens L1 and the second lens L2. For the convenience of description, each lens surface, the aperture stop STO, and the cover glass CG are numbered S1, S2 to S19. And the aspheric surface satisfies the following formula:

[0079]

[0080] In the above formula, z is the axial distance from the vertex of the surface at the position perpendicular to the optical axis with a height of y along the optical axis direction; c represents the curvature at the vertex of the aspheric surface; k is the conic coefficient; A4, A6, A8, A 10 、A 12 、A 14 、A 16 ··· represent the aspheric coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, sixteenth order, ··· respectively.

[0081] The data of the four groups of embodiments are as shown in Table 1 below:

[0082] Conditional Example 1 Example 2 Example 3 Example 4 -2.4 ≤ f1 / f ≤ -1.7 -1.976 -1.890 -1.840 -2.194 3 ≤ f2 / f ≤ 7.5 3.298 6.242 4.361 4.648 -4.6 ≤ f3 / f ≤ -2.65 -2.781 -4.413 -3.962 -3.122 1.5 ≤ f4 / f ≤ 1.8 1.706 1.667 1.656 1.627 1.1 ≤ f5 / f ≤ 1.46 1.232 1.182 1.367 1.294 -1.4 ≤ f6 / f ≤ -0.95 -1.051 -1.044 -1.066 -1.129 0.68 ≤ f7 / f ≤ 1.2 0.758 1.086 1.071 1.021 -5.8 ≤ f8 / f ≤ -1.2 -1.572 -4.802 -5.045 -3.932 1.3 ≤ (R31 + R32) / f ≤ 1.55 1.507 1.490 1.360 1.353 0.88 ≤ (R81 + R82) / f ≤ 1.17 0.935 1.120 1.050 0.947 0.025 ≤ CT34 / TTL ≤ 0.05 0.036 0.037 0.038 0.034 0.18 ≤ BFL / TTL ≤ 0.25 0.216 0.212 0.215 0.214 2.9 ≤ f*H / TTL ≤ 4 3.386 2.983 2.964 3.224 -1.85 ≤ fa / f ≤ -1.4 -1.696 -1.554 -1.661 -1.674 0.68 ≤ fb / f ≤ 0.88 0.800 0.813 0.829 0.784 -2.2 ≤ fa / fb ≤ -1.74 -2.119 -1.913 -2.003 -2.135

[0083] Embodiment 1

[0084] Figure 1 is a schematic structural diagram of the optical lens of Embodiment 1 in the present utility model;

[0085] Figure 2 Schematic diagram of F-Tan(theta) distortion of the optical lens in the first embodiment of the present utility model.

[0086] In the first embodiment, the first lens L1 is a convex-concave lens with a negative optical power, the second lens L2 is a concave-convex lens with a positive optical power, the third lens L3 is a convex-concave lens with a negative optical power, the fourth lens L4 is a plano-convex lens with a positive optical power, the fifth lens L5 is a concave-convex lens with a positive optical power, the sixth lens L6 is a concave-concave lens with a negative optical power, the seventh lens L7 is a convex-convex lens with a positive optical power, and the eighth lens L8 is a convex-concave lens with a negative optical power.

[0087] The first lens L1, the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all aspherical lenses; the aperture stop STO is located between the first lens L1 and the second lens L2.

[0088] Table 2 lists the relevant parameters of each lens in the optical lens of this embodiment, including: surface type, radius of curvature, thickness, refractive index of the material, and Abbe number.

[0089] Surface serial number Surface type Radius of curvature R Thickness d Refractive index Nd Abbe number Vd OBJ Spherical surface Infinity Infinity S1 Aspherical surface 7.8880 1.0990 1.537 55.98 S2 Aspherical surface 3.9320 1.3820 S3(STO) Spherical surface Infinity 0.2120 S4 Aspherical surface -107.1250 1.1980 1.640 23.53 S5 Aspherical surface -15.0160 0.0670 S6 Aspherical surface 7.6520 1.5090 1.640 23.53 S7 Aspherical surface 4.6380 0.8060 S8 Spherical surface Infinity 2.6830 1.755 52.34 S9 Spherical surface -10.5540 0.0720 S10 Aspherical surface 5.0250 2.5740 1.535 55.71 S11 Aspherical surface 58.7500 0.7940 S12 Aspherical surface -6.7090 1.0390 1.640 23.53 S13 Aspherical surface 33.6640 0.5100 S14 Aspherical surface 141.9450 2.4880 1.537 55.98 S15 Aspherical surface -3.3910 0.0650 S16 Aspherical surface 4.9660 1.1020 1.535 55.71 S17 Aspherical surface 2.6630 1.5000 S18 Spherical surface Infinity 0.7000 1.517 64.21 S19 Spherical surface Infinity 2.6500 IMA Spherical surface Infinity -

[0090] Table 2

[0091] Table 3 lists the aspherical coefficients of each aspherical lens in the optical lens of this embodiment, including: conic constant K of the surface, fourth-order aspherical coefficient A4, sixth-order aspherical coefficient A6, eighth-order aspherical coefficient A8, tenth-order aspherical coefficient A 10 , twelfth-order aspherical coefficient A 12 , fourteenth-order aspherical coefficient A 14 and sixteenth-order aspherical coefficient A 16 .

[0092]

[0093]

[0094] Table 3

[0095] Combined with Figure 1 , Figure 2 and as shown in Tables 1 to 3 above, in the first embodiment, the effective focal length f of the optical lens is 8.155, the field of view angle is 66°, and the optical distortion is -12%.

[0096] The first embodiment is an optical lens having at least one of the characteristics of a super large aperture FNO≤1.0, a long focal length f≥7.5mm, low cost, small size, large target surface (capable of matching chips larger than 1 / 1.8" inch), and no defocus within the temperature range of -40°C to 80°C. The chief ray angle of incidence (CRA) of the lens is <15°, and it can be adapted to most current mainstream chips.

[0097] Embodiment 2

[0098] Figure 3 It is a schematic structural diagram of the optical lens of Embodiment 2 in the present utility model;

[0099] Figure 4 It is a schematic diagram of the F-Tan(theta) distortion of the optical lens of Embodiment 2 in the present utility model.

[0100] In Embodiment 2, the first lens L1 is a convex-concave lens with a negative optical power, the second lens L2 is a convex-convex lens with a positive optical power, the third lens L3 is a convex-concave lens with a negative optical power, the fourth lens L4 is a convex-convex lens with a positive optical power, the fifth lens L5 is a convex-convex lens with a positive optical power, the sixth lens L6 is a concave-convex lens with a negative optical power, the seventh lens L7 is a convex-convex lens with a positive optical power, and the eighth lens L8 is a convex-concave lens with a negative optical power.

[0101] The first lens L1, the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all aspherical lenses; the aperture stop STO is located between the first lens L1 and the second lens L2.

[0102] Table 4 lists the relevant parameters of each lens in the optical lens of this embodiment, including: surface type, radius of curvature, thickness, refractive index of the material, and Abbe number.

[0103] Surface serial number Surface type Radius of curvature R Thickness d Refractive index Nd Abbe number Vd OBJ Spherical surface Infinity Infinity S1 Aspherical surface 5.4530 1.1800 1.537 55.98 S2 Aspherical surface 2.9500 1.8110 S3(STO) Spherical surface Infinity -0.0400 S4 Aspherical surface 185.6550 1.1000 1.640 23.53 S5 Aspherical surface -36.3710 0.0680 S6 Aspherical surface 6.6040 1.3430 1.640 23.53 S7 Aspherical surface 4.6510 0.8270 S8 Spherical surface 336.0000 2.7300 1.755 52.34 S9 Spherical surface -9.7960 0.0720 S10 Aspherical surface 5.3680 3.0020 1.535 55.71 S11 Aspherical surface -36.8440 0.6820 S12 Aspherical surface -4.7020 1.0650 1.640 23.53 S13 Aspherical surface -66.3380 0.0770 S14 Aspherical surface 328.8460 2.5240 1.537 55.98 S15 Aspherical surface -4.4750 0.0660 S16 Aspherical surface 4.8340 1.1720 1.640 23.53 S17 Aspherical surface 3.6260 1.5000 S18 Spherical surface Infinity 0.7000 1.517 64.21 S19 Spherical surface Infinity 2.5620 IMA Spherical surface Infinity -

[0104] Table 4

[0105] Table 5 lists the aspherical coefficients of each aspherical lens in the optical lens of this embodiment, including: the conic constant K of the surface, the fourth-order aspherical coefficient A4, the sixth-order aspherical coefficient A6, the eighth-order aspherical coefficient A8, the tenth-order aspherical coefficient A 10 , the twelfth-order aspherical coefficient A 12 , the fourteenth-order aspherical coefficient A 14 and the sixteenth-order aspherical coefficient A 16 .

[0106]

[0107]

[0108] Table 5

[0109] Combined with Figure 3 、 Figure 4 and as shown in Table 1, Table 4 and Table 5 above, combined with Figure 1 and Figure 2 and as shown in Table 1 to Table 3 above, in the second embodiment, the effective focal length f of the optical lens is 7.555, the field of view angle is 67°, and the optical distortion is -11.50%.

[0110] The second embodiment is an optical lens having at least one of the characteristics of a super large aperture FNO≤1.0, a long focal length f≥7.5mm, low cost, small volume, large target surface (capable of matching chips above 1 / 1.8" inch), no defocusing within the temperature range of -40°C to 80°C, etc. The incident angle of the principal ray of the lens CRA<15°, and it can be adapted to most of the current mainstream chips.

[0111] Embodiment Three

[0112] Figure 5 is a schematic structural diagram of the optical lens of Embodiment Three in the present utility model;

[0113] Figure 6 is a schematic diagram of the F-Tan(theta) distortion of the optical lens of Embodiment Three in the present utility model.

[0114] In Embodiment Three, the first lens L1 is a convex-concave lens with a negative optical power, the second lens L2 is a concave-convex lens with a positive optical power, the third lens L3 is a convex-concave lens with a negative optical power, the fourth lens L4 is a concave-convex lens with a positive optical power, the fifth lens L5 is a convex-convex lens with a positive optical power, the sixth lens L6 is a concave-concave lens with a negative optical power, the seventh lens L7 is a convex-convex lens with a positive optical power, and the eighth lens L8 is a convex-concave lens with a negative optical power.

[0115] The first lens L1, the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 are all aspherical lenses; the aperture stop STO is located between the first lens L1 and the second lens L2.

[0116] Table 6 lists the relevant parameters of each lens in the optical lens of this embodiment, including: surface type, radius of curvature, thickness, refractive index of the material and Abbe number.

[0117]

[0118]

[0119] Table 6

[0120] Table 7 lists the aspheric coefficients of each aspheric lens of the optical lens in this embodiment, including: the conic constant K of the surface, the fourth-order aspheric coefficient A4, the sixth-order aspheric coefficient A6, the eighth-order aspheric coefficient A8, and the tenth-order aspheric coefficient A 10 , the twelfth-order aspheric coefficient A 12 , the fourteenth-order aspheric coefficient A 14 , and the sixteenth-order aspheric coefficient A 16 .

[0121] Surface serial number K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S1 0.76 -3.1578E-03 9.3129E-05 -7.7324E-07 -3.3727E-08 2.2834E-10 0.0000E+00 0.0000E+00 S2 -2.13 2.3020E-04 -1.2976E-05 1.5341E-06 3.0982E-07 -2.2153E-08 0.0000E+00 0.0000E+00 S4 0.00 5.2806E-03 -7.7019E-04 3.9949E-05 -1.4122E-06 2.9024E-08 0.0000E+00 0.0000E+00 S5 0.00 8.8327E-03 -1.2343E-03 7.5123E-05 -2.5982E-06 4.9471E-08 0.0000E+00 0.0000E+00 S6 -5.76 -2.7144E-03 1.7784E-04 -1.7190E-05 9.8522E-07 -2.0281E-08 0.0000E+00 0.0000E+00 S7 -8.41 -2.9861E-03 2.4197E-04 -1.4388E-05 4.8169E-07 -6.9131E-09 0.0000E+00 0.0000E+00 S10 -1.85 -1.9144E-04 2.4310E-06 -1.1980E-06 6.1129E-08 -7.8402E-10 0.0000E+00 0.0000E+00 S11 0.00 4.7622E-04 -6.3075E-05 -2.1034E-06 2.1782E-07 -4.1046E-09 0.0000E+00 0.0000E+00 S12 -7.21 2.3207E-03 -1.1978E-04 1.7420E-06 5.2991E-08 -1.8013E-09 0.0000E+00 0.0000E+00 S13 0.00 3.1111E-03 -1.9797E-04 7.7198E-06 -1.0965E-07 -7.4224E-10 0.0000E+00 0.0000E+00 S14 0.00 2.0134E-03 -1.9793E-04 1.0699E-05 -2.4273E-07 2.7740E-09 0.0000E+00 0.0000E+00 S15 -2.22 4.6082E-03 -4.8326E-04 3.2503E-05 -1.1767E-06 1.9232E-08 0.0000E+00 0.0000E+00 S16 -7.39 1.9084E-03 -5.0922E-04 2.8617E-05 -8.8216E-07 1.1695E-08 0.0000E+00 0.0000E+00 S17 -6.07 4.4457E-05 -3.0093E-04 1.9345E-05 -5.9942E-07 7.8076E-09 0.0000E+00 0.0000E+00

[0122] Table 7

[0123] Combined with Figure 5 , Figure 6 and as shown in Table 1, Table 6 and Table 7 above, in Embodiment 3, the effective focal length f of the optical lens is 7.535, the field of view angle is 66.6°, and the optical distortion is -11%.

[0124] Embodiment 3 is an optical lens having at least one of the characteristics of a super large aperture FNO≤1.0, a long focal length f≥7.5mm, low cost, small volume, large target surface (capable of matching chips larger than 1 / 1.8" inches), and no defocusing within the temperature range of -40°C to 80°C. The chief ray angle of incidence CRA of the lens is <15°, and it can be adapted to most current mainstream chips.

[0125] Embodiment 4

[0126] Figure 7 is a schematic structural diagram of the optical lens of Embodiment 4 in the present utility model;

[0127] Figure 8 is a schematic diagram of the F-Tan(theta) distortion of the optical lens of Embodiment 4 in the present utility model.

[0128] In Embodiment 4, the first lens L1 is a convex-concave lens with a negative optical power, the second lens L2 is a concave-convex lens with a positive optical power, the third lens L3 is a convex-concave lens with a negative optical power, the fourth lens L4 is a plano-convex lens with a positive optical power, the fifth lens L5 is a convex-concave lens with a positive optical power, the sixth lens L6 is a concave-concave lens with a negative optical power, the seventh lens L7 is a convex-convex lens with a positive optical power, and the eighth lens L8 is a convex-concave lens with a negative optical power.

[0129] The first lens L1, the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all aspheric lenses; the aperture stop STO is located between the first lens L1 and the second lens L2.

[0130] Table 8 lists the relevant parameters of each lens in the optical lens of this embodiment, including: surface type, radius of curvature, thickness, refractive index of the material, and Abbe number.

[0131]

[0132]

[0133] Table 8

[0134] Table 9 lists the aspheric coefficients of each aspheric lens in the optical lens of this embodiment, including: conic constant K of the surface, fourth-order aspheric coefficient A4, sixth-order aspheric coefficient A6, eighth-order aspheric coefficient A8, tenth-order aspheric coefficient A 10 , twelfth-order aspheric coefficient A 12 , fourteenth-order aspheric coefficient A 14 and sixteenth-order aspheric coefficient A 16 .

[0135] Surface serial number K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S1 0.09 -2.8029E-03 -3.0591E-05 7.4863E-06 -3.4346E-07 5.2619E-09 0.0000E+00 0.0000E+00 S2 -1.90 8.6046E-04 -2.0034E-04 2.0262E-05 -5.9587E-07 1.8039E-09 0.0000E+00 0.0000E+00 S4 0.00 5.1196E-03 -8.0619E-04 5.2511E-05 -1.6000E-06 4.4067E-09 0.0000E+00 0.0000E+00 S5 0.00 8.4140E-03 -1.2953E-03 1.1230E-04 -5.3306E-06 9.8941E-08 0.0000E+00 0.0000E+00 S6 -5.09 -3.1178E-03 1.4837E-04 5.9479E-06 -8.4773E-07 2.0423E-08 0.0000E+00 0.0000E+00 S7 -8.68 -2.7101E-03 1.7312E-04 -6.1989E-06 5.7368E-08 7.6617E-10 0.0000E+00 0.0000E+00 S10 -1.70 -2.1471E-04 1.6601E-05 -6.2955E-07 2.4988E-08 -9.4822E-10 0.0000E+00 0.0000E+00 S11 0.00 -1.5527E-04 -1.8726E-05 -1.0668E-07 5.6187E-08 -2.3347E-09 0.0000E+00 0.0000E+00 S12 -7.16 1.5704E-03 -1.2361E-04 5.7446E-06 -9.8994E-08 -4.8106E-10 0.0000E+00 0.0000E+00 S13 0.00 4.1568E-03 -4.1711E-04 2.4027E-05 -6.3901E-07 5.8226E-09 0.0000E+00 0.0000E+00 S14 0.00 3.3897E-03 -4.2257E-04 3.0363E-05 -1.0471E-06 1.4918E-08 0.0000E+00 0.0000E+00 S15 -2.18 4.3561E-03 -4.5326E-04 3.3051E-05 -1.2926E-06 2.1491E-08 0.0000E+00 0.0000E+00 S16 -7.16 1.1112E-03 -3.9322E-04 2.2790E-05 -9.4150E-07 1.7642E-08 0.0000E+00 0.0000E+00 S17 -5.71 -1.1726E-03 -1.3867E-04 6.7138E-06 -1.6440E-07 2.3988E-09 0.0000E+00 0.0000E+00

[0136] Table 9

[0137] Combined with Figure 7 , Figure 8 and as shown in Table 1, Table 8 and Table 9 above, in the fourth embodiment, the effective focal length f of the optical lens is 8.066, the field of view angle is 63°, and the optical distortion is -9.40%.

[0138] The fourth embodiment is an optical lens having at least one of the characteristics of an ultra-large aperture FNO≤1.0, a long focal length f≥7.5mm, low cost, small size, large target surface (capable of matching chips larger than 1 / 1.8" inches), no defocusing within the temperature range of -40°C to 80°C, etc. The chief ray angle of incidence CRA of the lens is <15°, and it can be adapted to most current mainstream chips.

[0139] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An optical lens, comprising, in order from the object side to the image side along the optical axis: A first lens (L1) with negative focal power, a second lens (L2) with positive focal power, a third lens (L3) with negative focal power, a fourth lens (L4) with positive focal power, a fifth lens (L5) with positive focal power, a sixth lens (L6) with negative focal power, a seventh lens (L7) with positive focal power, and an eighth lens (L8) with negative focal power, characterized in that: The first lens (L1) is a convex-concave lens; The image side surface of the second lens (L2) is a convex surface; The third lens (L3) is a convex-concave lens; The eighth lens (L8) is a convex-concave lens; The effective focal length f8 of the eighth lens (L8) and the effective focal length f of the optical lens satisfy the following relationship: -5.8≤f8 / f≤-1.2; The effective focal length f of the optical lens, the total optical length TTL and the total image height H corresponding to the maximum field angle satisfy the following relationship: 2.9≤f*H / TTL≤4.

2. The optical lens according to claim 1, characterized in that: The image side surface of the fourth lens (L4) is a convex surface; The object side surface of the fifth lens (L5) is a convex surface; The object side surface of the sixth lens (L6) is a concave surface; The seventh lens (L7) is a convex-convex lens.

3. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f1 of the first lens (L1) and the effective focal length f of the optical lens satisfy the following relationship: -2.4≤f1 / f≤-1.

7.

4. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f2 of the second lens (L2) and the effective focal length f of the optical lens satisfy the following relationship: 3≤f2 / f≤7.

5.

5. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f3 of the third lens (L3) and the effective focal length f of the optical lens satisfy the following relationship: -4.6≤f3 / f≤-2.

65.

6. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f4 of the fourth lens (L4) and the effective focal length f of the optical lens satisfy the following relationship: 1.5≤f4 / f≤1.

8.

7. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f5 of the fifth lens (L5) and the effective focal length f of the optical lens satisfy the following relationship: 1.1≤f5 / f≤1.

46.

8. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f6 of the sixth lens (L6) and the effective focal length f of the optical lens satisfy the following relationship: -1.4≤f6 / f≤-0.

95.

9. The optical lens according to claim 1 or 2, characterized in that: The effective focal length f7 of the seventh lens (L7) and the effective focal length f of the optical lens satisfy the following relationship: 0.68≤f7 / f≤1.

2.

10. The optical lens according to claim 1 or 2, characterized in that: The curvature radius R31 of the object side surface and the curvature radius R32 of the image side surface of the third lens (L3) satisfy the following relationship with the effective focal length f of the optical lens: 1.3≤(R31+R32) / f≤1.

55.

11. The optical lens according to claim 1 or 2, characterized in that: The curvature radius R81 of the object side surface and the curvature radius R82 of the image side surface of the eighth lens (L8) satisfy the following relationship with the effective focal length f of the optical lens: 0.88≤(R81+R82) / f≤1.

17.

12. The optical lens according to claim 1 or 2, characterized in that: An air space CT34 between the third lens (L3) and the fourth lens (L4) and a total optical length TTL of the optical lens satisfy the following relationship: 0.025≤CT34 / TTL≤0.

05.

13. The optical lens according to claim 1 or 2, characterized in that: The back focal length BFL of the optical lens and the total optical length TTL satisfy the following relationship: 0.18≤BFL / TTL≤0.

25.

14. The optical lens according to claim 1 or 2, characterized in that: The effective focal length fa and the effective focal length f of the front lens group of the optical lens satisfy the following relationship: -1.85≤fa / f≤-1.

4.

15. The optical lens according to claim 1 or 2, characterized in that: The effective focal length fb and the effective focal length f of the rear lens group of the optical lens satisfy the following relationship: 0.68≤fb / f≤0.

88.

16. The optical lens according to claim 1 or 2, characterized in that: The effective focal length fa of the front lens group and the effective focal length fb of the rear lens group of the optical lens satisfy the following relationship: -2.2≤fa / fb≤-1.74.

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