Optical lens

Abstract

The application provides an optical lens, which comprises, along an optical axis from an object side to an imaging surface, a first lens with negative optical power, the object side of which is a convex surface and the image side of which is a concave surface; a second lens with negative optical power, the object side of which is a convex surface and the image side of which is a concave surface; a third lens with negative optical power, the object side of which is a concave surface and the image side of which is a convex surface; a fourth lens with positive optical power, the image side of which is a convex surface; a fifth lens with positive optical power, the object side of which is a convex surface and the image side of which is a convex surface; a sixth lens with negative optical power, the object side of which is a concave surface and the image side of which is a convex surface; a seventh lens with optical power, the object side of which is a concave surface; and an eighth lens with optical power, the object side of which is a convex surface and the image side of which is a concave surface. The optical lens provided by the application has the advantages of excellent imaging quality through specific surface shape setting and reasonable optical power distribution.

Description

Technical Field

[0001] This invention relates to the technical field of imaging lenses, and in particular to an optical lens. Background Technology

[0002] In recent years, with the rapid development of smart homes and security monitoring, smart surveillance cameras have entered thousands of households, becoming products that help people communicate with their families, record precious moments, and provide convenience for daily life. As the scope and scenarios for the use of smart surveillance cameras expand, people have higher demands for their performance, seeking high-definition imaging even in extreme environments like cold or heat, and the ability to clearly see the surroundings in low-light conditions. However, while current surveillance lenses on the market perform well in some aspects, there is still room for improvement in certain specific technical specifications.

[0003] Therefore, how to ensure high imaging quality in surveillance cameras is a problem that urgently needs to be solved. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0005] The technical solution adopted in this invention is as follows:

[0006] An optical lens, comprising eight lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0007] The first lens with negative optical power has a convex object side and a concave image side.

[0008] A second lens with negative optical power has a convex object side and a concave image side.

[0009] A third lens with negative optical power has a concave object side and a convex image side.

[0010] The fourth lens has positive optical power and its image-side surface is convex.

[0011] The fifth lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0012] The sixth lens with negative optical power has a concave object side and a convex image side.

[0013] The seventh lens, which has optical power, has a concave object side.

[0014] The eighth lens, which has optical power, has a convex object side and a concave image side.

[0015] Among them, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4 < TTL / f < 5.5; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.65 < TTL / IH < 2.1.

[0016] Further preferably, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -4 < f1234 / f5678 < -1.5.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -15 < f3 / f < -3; the curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: 0.4 < R5 / R6 < 1.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2 < f4 / f < 8.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.6 < f5 / f < 1.

[0020] Further preferably, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -2.5 < f3 / f4 < -0.8.

[0021] Further preferably, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1 < f5 / f6 < -0.01.

[0022] Further preferably, the focal length f7 of the seventh lens and the focal length f8 of the eighth lens satisfy: -1.5 < f7 / f8 < -0.1.

[0023] Further preferably, the effective focal length f of the optical lens and the combined focal length f56 of the fifth lens and the sixth lens satisfy: 0.8 < f56 / f < 1.8; the effective focal length f of the optical lens and the sum of the central thicknesses CT56 of the fifth lens and the sixth lens satisfy: 0.8 < CT56 / f < 1.8.

[0024] Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -15 < f7 / f < -1.

[0025] Further preferably, the effective focal length f of the optical lens and the focal length f8 of the eighth lens satisfy: 5 < f8 / f < 15.

[0026] Compared to existing technologies, the optical lens provided by this invention, through specific surface shape settings and reasonable power distribution, effectively shortens the overall length of the optical lens. Simultaneously, the lens also possesses a large image plane, achieving a better balance between miniaturization and a large image plane, thus enhancing market competitiveness. Furthermore, it can effectively correct overall aberrations of the optical lens, improving its imaging quality. Attached Figure Description

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0028] Figure 1 This is a schematic diagram of the optical lens structure in Embodiment 1 of the present invention.

[0029] Figure 2 This is an astigmatism curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 3 This is an axial aberration curve of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 4 This is a schematic diagram of the optical lens structure in Embodiment 2 of the present invention.

[0032] Figure 5 This is an astigmatism curve of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 6 This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 7 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0035] Figure 8 This is an astigmatism curve diagram of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 9 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 10 This is a schematic diagram of the optical lens structure in Embodiment 4 of the present invention.

[0038] Figure 11 This is an astigmatism curve of the optical lens in Embodiment 4 of the present invention.

[0039] Figure 12 This is an axial aberration curve of the optical lens in Embodiment 4 of the present invention.

[0040] Figure 13This is a schematic diagram of the optical lens in Embodiment 5 of the present invention.

[0041] Figure 14 This is an astigmatism curve diagram of the optical lens in Embodiment 5 of the present invention.

[0042] Figure 15 This is an axial aberration curve of the optical lens in Embodiment 5 of the present invention.

[0043] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0044] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0046] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0047] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0048] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0049] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so specified herein.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] The optical lens provided in this embodiment of the invention consists of eight lenses, which are arranged sequentially along the optical axis from the object side to the imaging plane as follows: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens.

[0052] In some embodiments, the first lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The second lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The third lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The fourth lens may have positive optical power, with either a concave or convex object-side surface and a convex image-side surface. The fifth lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The sixth lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The seventh lens may have either positive or negative optical power, with a concave object-side surface and either a concave or convex image-side surface. The eighth lens may have either positive or negative optical power, with a convex object-side surface and a concave image-side surface.

[0053] In some embodiments, the optical lens may also include an aperture stop, which may be located between the fourth and fifth lenses. It is understood that the aperture stop is used to limit the amount of light entering the lens to change the brightness of the image. When the aperture stop is located between the fourth and fifth lenses, it facilitates the correction of aperture aberrations.

[0054] In some embodiments, the optical lens may further include a filter, which may be disposed between the eighth lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0055] In some embodiments, the fifth lens and the sixth lens may be glued together to form a glued lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0056] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4 < TTL / f < 5.5. Meeting the above conditions can effectively limit the length of the lens and is conducive to the miniaturization of the optical lens.

[0057] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.65 < TTL / IH < 2.1. Meeting the above conditions, by reasonably restricting the ratio of the total length of the optical lens to the image height, it is ensured that the lens has a larger image surface under the same total length, achieving the balance of miniaturization and large image surface of the optical lens and improving the market competitiveness. [[ID=​​​​​​​​​In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.6 < f5 / f < 1. Meeting the above conditions and setting the fifth lens to have a large positive refractive power is beneficial to converging light while correcting the field curvature and distortion of the optical lens, and improving the imaging quality of the optical lens.

[0062] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -2.5 < f3 / f4 < -0.8. Meeting the above conditions is beneficial to enabling the diverging light to smoothly enter the rear optical system, reducing the difficulty of correcting field curvature and distortion, and improving the overall resolution.

[0063] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1 < f5 / f6 < -0.01. Meeting the above conditions and reasonably setting the focal length relationship between the fifth and sixth lenses can effectively correct the chromatic aberration of the system and improve the overall imaging quality.

[0064] In some embodiments, the focal length f7 of the seventh lens and the focal length f8 of the eighth lens satisfy: -1.5 < f7 / f8 < -0.1. Meeting the above conditions and reasonably setting the focal length relationship between the seventh and eighth lenses can diverge the light to a certain extent and effectively correct the aberration, which is beneficial to achieving large-format imaging of the lens.

[0065] In some embodiments, the effective focal length f of the optical lens and the combined focal length f56 of the fifth and sixth lenses satisfy: 0.8 < f56 / f < 1.8; the effective focal length f of the optical lens and the sum of the central thicknesses CT56 of the fifth and sixth lenses satisfy: 0.8 < CT56 / f < 1.8. Meeting the above conditions, the fifth and sixth lenses form a cemented lens with positive optical power. By reasonably setting the focal length and thickness of the fifth and sixth cemented lenses, the incident light can be further converged, the light energy loss can be reduced, and at the same time, the diverging light can be made to converge and smoothly enter the rear, further making the light trend transition smoothly and improving the relative illumination of the edge field of view.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -15 < f7 / f < -1. Meeting the above conditions makes the seventh lens have an appropriate negative optical power, which is beneficial to diverging the light in the central field of view to a certain extent, and at the same time, combining with the curvature of the edge field of view to reduce the exit angle of the light in the edge field of view and improve the relative illumination of the edge field of view.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f8 of the eighth lens satisfy: 5 < f8 / f < 15. Meeting the above conditions makes the eighth lens have an appropriate positive optical power, which is beneficial to increasing the area of light entering the imaging surface, achieving large-format imaging of the lens, and improving the imaging quality of the optical lens.

[0068] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV of the optical lens, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 60° < (f × FOV) / IH < 80°. Meeting the above conditions, by reasonably restricting the relationship between the focal length, the field of view angle, and the image height of the optical lens, it is possible to ensure that the optical lens has the characteristics of a large field of view and a large image plane, thereby enabling the optical lens to have good optical performance and being able to capture the details of the photographed object well.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -30 < f1 / f < -1. Meeting the above conditions, by setting the first lens to have a negative refractive power, it is beneficial for the first lens to receive light at a larger angle and collect as much light as possible into the rear optical system, increasing the light flux while achieving a large field of view.

[0070] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -40 < f2 / f < -1. Meeting the above conditions helps the light to transition smoothly, expands the field of view angle of the optical imaging lens, reduces the difficulty of correcting distortion and chromatic aberration for the rear lenses, and improves the image quality of the optical imaging lens.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -60 < f6 / f < -0.8. Meeting the above conditions can make the sixth lens have an appropriate negative optical power, which is beneficial for balancing the astigmatism and field curvature of the optical lens and improving the imaging quality of the optical lens.

[0072] In some embodiments, the central thickness CT5 of the fifth lens and the central thickness CT6 of the sixth lens satisfy: 2 < CT5 / CT6 < 10. Meeting the above conditions can reduce the sensitivity of the system performance, while ensuring the lens processing performance and assembly stability, and improving the assembly yield.

[0073] In some embodiments, the effective focal length f of the optical lens and the combined focal length f1234 of the first lens, the second lens, the third lens, and the fourth lens satisfy: -6 < f1234 / f < -1.5. Meeting the above conditions, by reasonably setting the negative refractive power of the front diaphragm lens group, it is beneficial for converging light within a large angular range to achieve the ultra-wide angle characteristic, while improving the resolution of the edge field of view, and achieving a balance between a shorter total optical lens length and good imaging quality.

[0074] In some embodiments, the effective focal length f of the optical lens and the combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens, and the eighth lens satisfy: 1.1 < f5678 / f < 1.8. Meeting the above conditions, by reasonably setting the positive refractive power of the rear diaphragm lens group, it is beneficial to balance the distortion and astigmatism generated by the front-end lens of the optical lens, and improve the imaging quality of the optical lens.

[0075] In some embodiments, the optical lens satisfies the conditional formula: 16 mm < TTL < 17.5 mm, 3 mm < f < 4.5 mm, 8.5 mm < IH < 9.5 mm, Fno < 2.2, 160° < FOV < 170°; 13° < CRA < 15°; where TTL represents the overall optical length of the optical lens, f represents the effective focal length of the optical lens, IH represents the true image height corresponding to the maximum viewing angle of the optical lens, Fno represents the aperture value of the optical lens, FOV represents the maximum viewing angle of the optical lens, and CRA represents the principal ray incident angle at the maximum image height of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of miniaturization, large viewing angle, large image plane, etc.

[0076] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. On the other hand, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The first lens in the optical lens provided by the present invention uses a glass lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens use plastic lenses.

[0077] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens can use spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the first lens of the present invention uses a spherical lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens can all use aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens.

[0078] In each embodiment of the present invention, when the lens uses an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0079]

[0080] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, F, G, and H are the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order surface coefficients, respectively.

[0081] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0082] Example 1

[0083] Please see Figure 1 The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane, the following components in sequence: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter G1.

[0084] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0085] The second lens L2 has negative optical power, its object side S3 is convex, and its image side S4 is concave.

[0086] The third lens L3 has negative optical power, its object side S5 is concave, and its image side S6 is convex.

[0087] The fourth lens L4 has positive optical power, its object side S7 is concave, and its image side S8 is convex.

[0088] The fifth lens L5 has positive optical power, its object side S9 is convex, and its image side S10 is convex.

[0089] The sixth lens L6 has negative optical power, its object side S10 is concave, and its image side S11 is convex.

[0090] The fifth lens L5 and the sixth lens L6 form a cemented lens group with positive optical power, that is, the cemented surface of the image side of the fifth lens L5 and the object side of the sixth lens L6 is S10.

[0091] The seventh lens L7 has positive optical power, its object side surface S12 is concave, and its image side surface S13 is convex.

[0092] The eighth lens L8 has negative optical power, its object side S14 is convex, and its image side S15 is concave.

[0093] The object-side surface S16 and the image-side surface S17 of filter G1 are both planar.

[0094] The imaging plane S18 is a plane.

[0095] The first lens L1 is a glass spherical lens, while the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all plastic aspherical lenses.

[0096] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0097] Table 1-1

[0098]

[0099]

[0100] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0101] Table 1-2

[0102]

[0103] Figure 2 The diagram shows the astigmatism curve of the optical lens 100 in this embodiment, which represents the astigmatism of light in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the field of view (unit: °). As can be seen from the figure, the astigmatism in the meridional and sagittal image planes is controlled within ±0.1 mm, indicating that the optical lens 100 can correct astigmatism well.

[0104] Figure 3 The diagram shows the axial aberration curve of the optical lens 100 in the embodiment, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the axial aberration offset is controlled within ±0.04 mm, indicating that the optical lens 100 can correct axial aberration well.

[0105] Example 2

[0106] Please see Figure 4The figure shows a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S7 of the fourth lens L4 is a convex surface; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0107] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0108] Table 2-1

[0109]

[0110] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0111] Table 2-2

[0112] Face number K B C D E F G H S3 6.29E-01 9.59E-03 -8.16E-04 -1.37E-05 6.50E-07 7.36E-08 1.71E-09 -2.02E-10 S4 2.99E-03 1.50E-02 5.40E-05 -3.77E-04 -3.41E-05 -4.76E-06 -6.97E-08 1.42E-07 S5 -2.69E+00 4.84E-03 1.67E-04 -5.65E-05 -3.68E-06 8.51E-07 1.75E-07 -2.35E-08 S6 -2.60E+00 1.08E-02 3.67E-04 -1.44E-04 -1.12E-05 -2.91E-06 -6.55E-07 2.22E-07 S7 1.00E+02 2.84E-03 -4.61E-03 9.76E-04 -8.89E-05 -8.07E-05 -8.82E-06 3.20E-06 S8 6.29E+01 -1.87E-03 -2.82E-03 -2.03E-04 1.88E-04 -8.70E-06 -3.75E-05 9.21E-06 S9 -4.04E-01 -1.66E-03 -1.18E-03 -1.11E-04 4.05E-05 1.37E-05 1.79E-06 -1.25E-06 S10 -7.70E-01 1.14E-02 2.16E-03 2.20E-04 -1.27E-05 -4.17E-06 1.63E-07 3.75E-07 S11 -2.79E+00 3.35E-03 4.23E-04 6.12E-06 1.33E-06 1.09E-07 3.93E-09 -1.58E-09 S12 -2.74E+00 5.97E-03 2.41E-04 -9.60E-06 -1.83E-06 5.44E-08 2.70E-08 -1.90E-09 S13 -3.00E+00 6.40E-03 2.26E-04 -3.91E-06 -1.55E-07 -4.62E-09 -4.79E-09 1.64E-10 S14 -5.83E+01 -1.95E-03 1.22E-04 6.40E-06 3.48E-08 -1.76E-08 -5.82E-10 4.15E-11 S15 -7.88E+00 -8.78E-03 2.98E-04 -5.64E-06 -1.53E-07 2.18E-08 1.94E-09 -1.03E-10

[0113] In this embodiment, the astigmatism curve and axial aberration curve of the optical lens 200 are respectively as follows: Figure 5 , Figure 6 As shown.

[0114] from Figure 5 As can be seen, the astigmatism of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 200 can correct astigmatism well.

[0115] from Figure 6 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens 200 can correct axial aberration well.

[0116] Example 3

[0117] Please see Figure 7 The figure shows a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the seventh lens L7 has negative optical power; the eighth lens L8 has positive optical power; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0118] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0119] Table 3-1

[0120]

[0121]

[0122] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0123] Table 3-2

[0124] Face number K B C D E F G H S3 -3.60E+00 5.00E-05 -3.49E-05 -3.54E-06 -1.26E-07 -6.43E-09 -4.37E-10 -7.29E-12 S4 1.88E+00 1.49E-04 -2.96E-04 -3.77E-05 -4.76E-06 -4.96E-07 -1.12E-07 -2.90E-08 S5 -2.36E+00 7.79E-04 1.33E-04 2.74E-06 -1.01E-07 2.16E-08 8.80E-09 -3.43E-10 S6 -4.84E+00 1.42E-03 2.65E-04 2.39E-05 1.71E-06 1.13E-07 1.34E-08 -5.80E-10 S7 1.00E+02 -4.35E-04 -1.45E-04 -9.72E-06 2.76E-06 -2.52E-08 -1.69E-07 -8.66E-08 S8 3.27E+00 -1.67E-03 2.83E-04 2.20E-05 -8.48E-06 -2.83E-06 -2.85E-07 1.53E-07 S9 2.65E-02 -2.87E-04 -5.88E-06 5.43E-06 9.92E-07 8.19E-08 -8.79E-09 -5.80E-09 S10 -1.24E+00 -2.17E-03 -1.65E-04 -1.62E-05 1.21E-06 6.68E-07 1.24E-07 1.76E-08 S11 -1.82E+00 -7.10E-04 2.41E-06 1.00E-05 1.09E-06 7.53E-08 3.97E-09 5.17E-11 S12 3.50E+00 2.93E-04 2.23E-04 3.43E-06 -7.07E-07 -3.92E-08 9.01E-09 4.19E-09 S13 4.67E+00 9.26E-04 7.92E-06 -5.83E-08 -2.19E-07 -2.61E-08 -1.30E-09 2.02E-10 S14 -1.91E+00 -6.72E-04 -3.04E-05 -5.20E-07 1.94E-08 2.87E-10 7.77E-11 -3.53E-12 S15 -3.45E+01 -2.00E-03 -4.47E-05 7.66E-07 4.81E-08 -8.38E-11 -8.53E-11 -1.88E-12

[0125] In this embodiment, the astigmatism curve and axial aberration curve of the optical lens 300 are respectively as follows: Figure 8 , Figure 9 As shown.

[0126] from Figure 8 As can be seen, the astigmatism of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 300 can correct astigmatism well.

[0127] from Figure 9 As can be seen, the axial aberration offset is controlled within ±0.04mm, indicating that the optical lens 300 can correct axial aberration well.

[0128] Example 4

[0129] Please see Figure 10 The figure shows a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that: the seventh lens L7 has negative optical power; the eighth lens L8 has positive optical power; the object side S7 of the fourth lens L4 is convex; the image side S13 of the seventh lens L7 is concave; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0130] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0131] Table 4-1

[0132]

[0133] The surface profile parameters of the aspherical lens in Example 4 are shown in Table 4-2.

[0134] Table 4-2

[0135]

[0136]

[0137] In this embodiment, the astigmatism curve and axial aberration curve of the optical lens 400 are respectively as follows: Figure 11 , Figure 12 As shown.

[0138] from Figure 11 As can be seen, the astigmatism of the meridional and sagittal image planes is controlled within ±0.15mm, indicating that the optical lens 400 can correct astigmatism well.

[0139] from Figure 12 As can be seen, the axial aberration offset is controlled within ±0.04mm, indicating that the optical lens 400 can correct axial aberration well.

[0140] Example 5

[0141] Please see Figure 13 The diagram shows a schematic of the structure of the optical lens 500 provided in Embodiment 5 of the present invention. The main difference between this embodiment and Embodiment 1 is that the seventh lens L7 has negative optical power; the eighth lens L8 has positive optical power; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0142] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0143] Table 5-1

[0144]

[0145]

[0146] The surface profile parameters of the aspherical lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0147] Table 5-2

[0148] Face number K B C D E F G H S3 -1.18E+00 3.99E-04 -3.45E-04 -2.21E-05 2.22E-07 2.34E-07 1.32E-08 -5.01E-09 S4 3.85E+00 -1.56E-03 -1.01E-03 -7.46E-05 2.35E-06 1.62E-07 -1.46E-07 -5.98E-08 S5 -2.27E+00 2.06E-03 7.81E-04 -1.96E-05 -1.41E-05 -1.04E-06 3.75E-08 4.48E-08 S6 -7.98E+00 2.72E-03 8.03E-04 9.01E-05 -4.21E-06 -3.79E-06 -6.78E-07 -9.75E-08 S7 -2.64E+02 -4.26E-04 -6.74E-04 -1.39E-04 -1.66E-05 -7.55E-07 4.00E-08 -7.71E-08 S8 4.81E+00 -2.07E-03 -7.48E-05 -7.53E-05 -3.37E-05 -5.89E-06 5.55E-08 8.30E-07 S9 -3.05E-01 -6.14E-04 -1.53E-04 -4.14E-07 2.20E-06 3.24E-07 8.68E-09 -7.91E-09 S10 -9.97E-01 -5.27E-03 2.30E-04 5.61E-05 1.41E-05 2.04E-06 1.17E-07 -5.35E-08 S11 -1.39E+00 -1.73E-03 8.08E-05 2.18E-05 1.42E-06 8.75E-10 -3.93E-09 1.34E-09 S12 2.22E+00 3.33E-03 -3.39E-04 -1.86E-05 3.09E-06 6.89E-07 5.72E-08 -5.75E-09 S13 -7.05E+00 1.26E-03 1.41E-04 8.81E-06 5.04E-07 2.60E-08 -1.56E-09 -9.73E-10 S14 -1.02E+01 -1.18E-03 3.42E-05 3.09E-06 5.93E-08 -1.69E-09 -1.17E-10 4.65E-12 S15 -1.44E+01 -5.34E-03 -1.15E-05 3.30E-06 1.28E-07 5.23E-09 1.75E-10 -3.09E-12

[0149] In this embodiment, the astigmatism curve and axial aberration curve of the optical lens 500 are respectively as follows: Figure 14 , Figure 15 As shown.

[0150] from Figure 14 As can be seen, the astigmatism of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 500 can correct astigmatism well.

[0151] from Figure 15 As can be seen, the axial aberration offset is controlled within ±0.05mm, indicating that the optical lens 500 can correct axial aberration well.

[0152] Please refer to Table 6 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, principal ray incident angle CRA at the maximum image height, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0153] Table 6

[0154]

[0155]

[0156] In summary, the optical lens provided by the present invention has at least the following advantages:

[0157] (1) By setting specific surface shapes and allocating reasonable optical power, the lens achieves an ultra-wide angle, thereby acquiring more scene information and meeting the needs of wide-range shooting. Effectively shortening the overall length of the optical lens is beneficial for miniaturization, which is in line with the current trend of increasingly lightweight and high-performance security lenses.

[0158] (2) The optical lens of the present invention can reasonably correct the overall aberration of the optical lens, reduce aberration, improve the resolution of the optical lens, achieve high-definition imaging, and improve the imaging quality of the optical lens.

[0159] (3) The glass-plastic hybrid structure is adopted to improve the stability of the lens under high and low temperature conditions and improve the imaging quality; at the same time, the lens has a small CRA, which can match the chip well and ensure good resolution quality.

[0160] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0161] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens consisting of eight pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, successively comprises: a first lens with negative refractive power, the object side surface of which is convex, and the image side surface of which is concave; a second lens with negative refractive power, the object side surface of which is convex, and the image side surface of which is concave; a third lens with negative refractive power, the object side surface of which is concave, and the image side surface of which is convex; a fourth lens with positive refractive power, the image side surface of which is convex; a fifth lens with positive refractive power, the object side surface of which is convex, and the image side surface of which is convex; a sixth lens with negative refractive power, the object side surface of which is concave, and the image side surface of which is convex; a seventh lens with refractive power, the object side surface of which is concave; an eighth lens with refractive power, the object side surface of which is convex, and the image side surface of which is concave; wherein the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4 < TTL / f < 5.5; the total track length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.65 < TTL / IH < 2.

1.

2. The optical lens of claim 1, wherein, The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -4 < f1234 / f5678 < -1.

5.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -15 < f3 / f < -3; the object side surface curvature radius R5 of the third lens and the image side surface curvature radius R6 of the third lens satisfy: 0.4 < R5 / R6 < 1.

4. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2 < f4 / f < 8.

5. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.6 < f5 / f < 1.

6. The optical lens of claim 1, wherein, The focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -2.5 < f3 / f4 < -0.

8.

7. The optical lens of claim 1, wherein, The focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1 < f5 / f6 < -0.

01.

8. The optical lens of claim 1, wherein, The focal length f7 of the seventh lens and the focal length f8 of the eighth lens satisfy: -1.5 < f7 / f8 < -0.

1.

9. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the combined focal length f56 of the fifth lens and the sixth lens satisfy: 0.8 < f56 / f < 1.8; the effective focal length f of the optical lens and the sum CT56 of the central thicknesses of the fifth lens and the sixth lens satisfy: 0.8 < CT56 / f < 1.

8.

10. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -15 < f7 / f < -1.

11. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f8 of the eighth lens satisfy: 5 < f8 / f < 15.

Images