Optical lens

Abstract

The application provides an optical lens, which comprises eight lenses with optical power, and sequentially comprises, along an optical axis from an object side to an imaging surface: a first lens with negative optical power, wherein an object side surface of the first lens is a concave surface and an image side surface of the first lens is a convex surface; a second lens with positive optical power, wherein an object side surface of the second lens is a convex surface and an image side surface of the second lens is a convex surface; a third lens with negative optical power, wherein an image side surface of the third lens is a concave surface; a fourth lens with positive optical power, wherein an object side surface of the fourth lens is a convex surface and an image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein an image side surface of the fifth lens is a convex surface; a sixth lens with negative optical power, wherein an object side surface of the sixth lens is a concave surface; a seventh lens with negative optical power, wherein an object side surface of the seventh lens is a concave surface and an image side surface of the seventh lens is a concave surface; and an eighth lens with negative optical power. The optical lens provided by the application has one or more advantages such as long focus, large aperture, high imaging quality and the like.

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 today's booming development of automotive driver assistance and autonomous driving technologies, in-vehicle cameras play a crucial role. There are various types of in-vehicle cameras, including interior, rear, front, side, and surround view cameras. Each has unique functions and different application scenarios. For example, the main function of a front-view wide-angle camera is to accurately identify nearby objects, providing crucial information for driving in urban road conditions and low-speed driving scenarios.

[0003] The forward-facing camera is a core component of ADAS (Advanced Driver Assistance Systems). It not only bears the crucial responsibility of distance measurement but also accurately identifies objects and clearly distinguishes road markings. Therefore, the required visual algorithms are extremely complex, posing a high technical barrier. To fully utilize the performance of the forward-facing camera, developing an optical lens with superior imaging capabilities is of paramount importance. Only in this way can we ensure its stable and efficient operation in complex driving environments, laying a solid foundation for the further development of autonomous driving technology. 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 comprises eight lenses with optical power, arranged sequentially along the optical axis from the object side to the imaging plane:

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

[0008] A second lens with positive optical power has a convex object-side surface and a convex image-side surface;

[0009] The third lens with negative optical power has a concave image-side surface;

[0010] The fourth lens with positive optical power has a convex object-side surface and a convex image-side surface.

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

[0012] The sixth lens has negative optical power and its object side is concave.

[0013] The seventh lens with negative optical power has a concave object side and a concave image side.

[0014] an eighth lens with negative optical power;

[0015] wherein the combined focal length f56 of the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy: 1<f56 / f<18.

[0016] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.6<TTL / f<2; the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 2.8<TTL / IH<3.4.

[0017] Further preferably, the real image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens and the maximum field of view FOV of the optical lens satisfy: 0.99<(IH / 2) / (f×Tan(FOV / 2))<1.04; the clear aperture half-diameter d1 of the object side of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens and the maximum field of view FOV of the optical lens satisfy: 4<d1 / (IH / 2) / Tan(FOV / 2)<4.8.

[0018] Further preferably, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.2<f1 / f<-1.4; the curvature radius R1 of the object side of the first lens and the effective focal length f of the optical lens satisfy: -0.4<R1 / f<-0.2; the curvature radius R2 of the image side of the first lens and the effective focal length f of the optical lens satisfy: -0.6<R2 / f<-0.3.

[0019] Further preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 0.6<f2 / f<0.9; the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.4<R3 / f<0.7; the curvature radius R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: -5<R4 / f<-1.2.

[0020] Further preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -0.8<f3 / f<-0.4; the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: -2.5<f8 / f<-0.8.

[0021] Further preferably, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.75<f5 / f<1.5; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -3.3<f6 / f<-1.1.

[0022] Further preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.1<f7 / f<-1; the radius of curvature R13 of the object-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: -2.7<R13 / f<-1.5; the radius of curvature R14 of the image-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.8<R14 / f<2.9.

[0023] Further preferably, the combined focal length f12 of the first lens and the second lens and the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens satisfy: 1<f12 / f1234<1.8; the combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -24<f56 / f5678<-0.3.

[0024] Further preferably, the radius of curvature R1 of the object-side surface of the first lens and the radius of curvature R2 of the image-side surface of the first lens satisfy: -0.3<(R1-R2) / (R1+R2)<-0.1; or the radius of curvature R3 of the object-side surface of the second lens and the radius of curvature R4 of the image-side surface of the second lens satisfy: -0.9<(R3+R4) / (R3-R4)<-0.4; or the radius of curvature R13 of the object-side surface of the seventh lens and the radius of curvature R14 of the image-side surface of the seventh lens satisfy: |(R13+R14) / (R13-R14)|<0.5.

[0025] The optical lens provided by the present invention adopts eight lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, can improve the imaging quality of the optical lens, reduce aberrations, enhance the imaging quality of the optical lens, and endow the lens with one or more advantages such as long focal length, large aperture, and high imaging quality. Brief Description of the Drawings

[0026] 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:

[0027] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 2 is an MTF curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 3 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0030] Figure 4This is the MTF curve of the optical lens in Embodiment 2 of the present invention.

[0031] Figure 5 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0032] Figure 6 This is an MTF curve of the optical lens in Embodiment 3 of the present invention.

[0033] Figure 7 This is a schematic diagram of the optical lens structure in Embodiment 4 of the present invention.

[0034] Figure 8 This is the MTF curve of the optical lens in Embodiment 4 of the present invention.

[0035] Figure 9 This is a schematic diagram of the optical lens structure in Embodiment 5 of the present invention.

[0036] Figure 10 This is the MTF curve of the optical lens in Embodiment 5 of the present invention.

[0037] Figure 11 This is a schematic diagram of the optical lens in Embodiment 6 of the present invention.

[0038] Figure 12 This is the MTF curve of the optical lens in Embodiment 6 of the present invention.

[0039] Figure 13 This is a schematic diagram of the optical lens in Embodiment 7 of the present invention.

[0040] Figure 14 This is the MTF curve of the optical lens in Embodiment 7 of the present invention.

[0041] Figure 15 This is a schematic diagram of the optical lens in Embodiment 8 of the present invention.

[0042] Figure 16 This is the MTF curve of the optical lens in Embodiment 8 of the present invention.

[0043] Figure 17 This is a schematic diagram of the optical lens structure in Embodiment 9 of the present invention.

[0044] Figure 18 This is the MTF curve of the optical lens in Embodiment 9 of the present invention.

[0045] Figure 19 This is a schematic diagram of the optical lens in Embodiment 10 of the present invention.

[0046] Figure 20 This is the MTF curve of the optical lens in Embodiment 10 of the present invention.

[0047] Figure 21 This is a schematic diagram of the optical lens structure in Embodiment 11 of the present invention.

[0048] Figure 22 This is the MTF curve of the optical lens in Embodiment 11 of the present invention.

[0049] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] The optical lens provided in this embodiment of the invention includes eight lenses with optical power, which are arranged sequentially from the object side to the imaging plane along the optical axis as 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.

[0058] In some embodiments, the first lens may have negative optical power, its object-side surface may be concave, and its image-side surface may be convex. The second lens may have positive optical power, its object-side surface may be convex, and its image-side surface may be convex. The third lens may have negative optical power, its object-side surface may be concave or convex, and its image-side surface may be concave. The fourth lens may have positive optical power, its object-side surface may be convex, and its image-side surface may be convex. The fifth lens may have positive optical power, its object-side surface may be convex or concave, and its image-side surface may be convex. The sixth lens may have negative optical power, its object-side surface may be concave, and its image-side surface may be convex or concave. The seventh lens may have negative optical power, its object-side surface may be concave, and its image-side surface may be concave. The eighth lens may have negative optical power, its object-side surface may be concave or convex, and its image-side surface may be convex or concave.

[0059] In some embodiments, the optical lens may also include an aperture stop, which may be located between the first lens and the second lens. It is understood that the aperture stop is used to limit the amount of light entering the lens, thereby altering the brightness of the image.

[0060] In some embodiments, the optical lens may further include a filter and a protective glass, which are sequentially disposed along the optical axis between the eighth lens and the imaging plane. The filter is used to filter out interfering light, preventing it from reaching the imaging plane of the optical lens and affecting normal imaging. The protective glass protects the optical lens, preventing damage to the image sensor, and improves the lens's shock and scratch resistance, while having almost no impact on the image quality of the optical lens.

[0061] In some embodiments, the third lens and the fourth lens may be cemented to form a cemented 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 lowering the difficulty of the processing technology of the optical lens and increasing the assembly yield of the optical lens.

[0062] In some embodiments, the combined focal length f56 of the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy: 1<f56 / f<18. Meeting the above range is beneficial for the system to have a longer focal length and meet the telephoto characteristic. More specifically: 1.05<f56 / f<16.95.

[0063] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.6<TTL / f<2; the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 2.8<TTL / IH<3.4. Meeting the above range is conducive to achieving the balance between small volume and large image plane of the optical lens, so that the lens has a relatively small total length. More specifically: 1.72<TTL / f<1.93; 3.04<TTL / IH<3.37.

[0064] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens and the maximum field of view FOV of the optical lens satisfy: 0.99<(IH / 2) / (f×Tan(FOV / 2))<1.04; the clear aperture half-diameter d1 of the object side of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens and the maximum field of view FOV of the optical lens satisfy: 4<d1 / (IH / 2) / Tan(FOV / 2)<4.8. Meeting the above range can control the optical lens to have relatively small distortion and improve the imaging quality. At the same time, the overall geometric shape of the optical lens can be reasonably arranged to improve its structural stability. More specifically: 4.17<d1 / (IH / 2) / Tan(FOV / 2)<4.48.

[0065] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.2<f1 / f<-1.4; the curvature radius R1 of the object-side surface of the first lens and the effective focal length f of the optical lens satisfy: -0.4<R1 / f<-0.2; the curvature radius R2 of the image-side surface of the first lens and the effective focal length f of the optical lens satisfy: -0.6<R2 / f<-0.3. Satisfying the above ranges and reasonably defining the focal power proportion and surface profile of the first lens can collect light rays at a large field of view to a greater extent, allow the light rays to enter the rear optical system, increase the luminous flux and improve the field of view angle at the same time. More specifically: -2.01<f1 / f<-1.47; -0.38<R1 / f<-0.27; -0.59<R2 / f<-0.38.

[0066] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 0.6<f2 / f<0.9; the curvature radius R3 of the object-side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.4<R3 / f<0.7; the curvature radius R4 of the image-side surface of the second lens and the effective focal length f of the optical lens satisfy: -5<R4 / f<-1.2. Satisfying the above ranges and reasonably defining the focal power proportion and surface profile of the second lens is beneficial to converging light rays while reducing the deflection angle of the light rays, shortening the distance for the light rays to reach the next lens, and helping to reduce the total length of the lens. More specifically: 0.69<f2 / f<0.87; 0.49<R3 / f<0.66; -4.86<R4 / f<-1.37.

[0067] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -0.8<f3 / f<-0.4; the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: -2.5<f8 / f<-0.8. Satisfying the above ranges can effectively balance the aberrations of the lens and improve the imaging quality. More specifically: -0.75<f3 / f<-0.48; -2.41<f8 / f<-0.87.

[0068] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.75<f5 / f<1.5; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -3.3<f6 / f<-1.1. Satisfying the above ranges helps to smooth the trend of light rays from the front-end lenses, correct the aberrations generated by the front-end lenses, and improve the imaging quality. More specifically: 0.77<f5 / f<1.36; -3.01<f6 / f<-1.23.

[0069] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.1<f7 / f<-1; the radius of curvature R13 of the object-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: -2.7<R13 / f<-1.5; the radius of curvature R14 of the image-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.8<R14 / f<2.9. Meeting the above ranges, by reasonably limiting the refractive power proportion and the surface profile of the seventh lens, the aberration generated at the front end of the lens can be effectively corrected, and the imaging quality of the lens can be improved. More specifically: -1.92<f7 / f<-1.05; -2.53<R13 / f<-1.63; 0.9<R14 / f<2.69.

[0070] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens satisfy: 1<f12 / f1234<1.8; the combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -24<f56 / f5678<-0.3. Meeting the above ranges is beneficial to improving field curvature, so that the details of the entire frame fall on the same focal plane. More specifically: 1.06<f12 / f1234<1.63; -21.91<f56 / f5678<-0.34.

[0071] In some embodiments, the radius of curvature R1 of the object-side surface of the first lens and the radius of curvature R2 of the image-side surface of the first lens satisfy: -0.3<(R1-R2) / (R1+R2)<-0.1; the radius of curvature R3 of the object-side surface of the second lens and the radius of curvature R4 of the image-side surface of the second lens satisfy: -0.9<(R3+R4) / (R3-R4)<-0.4; the radius of curvature R13 of the object-side surface of the seventh lens and the radius of curvature R14 of the image-side surface of the seventh lens satisfy: |(R13+R14) / (R13-R14)|<0.5. Meeting the above ranges can correct the aberration of the optical lens, and ensure that the light passing through the first, second and seventh lenses travels smoothly, reducing the tolerance sensitivity of the optical lens. More specifically: -0.24<(R1-R2) / (R1+R2)<-0.15; -0.81<(R3+R4) / (R3-R4)<-0.42; -0.16<(R13+R14) / (R13-R14)<0.46.

[0072] In some embodiments, the maximum field of view FOV of the optical lens and the F-number Fno of the optical lens satisfy: 18°<FOV / Fno<19°. Satisfying the above range, which reasonably limits the ratio of the field of view to the F-number, enables the collection of light at large angles and obtains good imaging quality. More specifically: 18.3°<FOV / Fno<18.4°.

[0073] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 0.9<IH / EPD<1. Satisfying the above range, which reasonably limits the ratio of the image height to the entrance pupil diameter, is beneficial to increasing the light throughput, and making the brightness of the peripheral field of view and the central field of view more uniform. More specifically: 0.94<IH / EPD<0.99.

[0074] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 0.5<IH / f<0.6. Satisfying the above range, which controls the image height and focal length of the optical lens within a reasonable range, helps the optical lens have the characteristic of a large image plane, and improves the imaging quality. More specifically: 0.55<IH / f<0.59.

[0075] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.14<BFL / f<0.18. Satisfying the above range limits the optical lens to have an appropriate back focal length, which facilitates reasonable arrangement of the positions of the respective lenses, and reduces the difficulty of processing and assembly at the same time.

[0076] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 0.4<f4 / f<0.7. Satisfying the above range, by reasonably limiting the proportion of the optical power of the fourth lens, can optimize spherical aberration and achieve high-quality imaging. More specifically: 0.47<f4 / f<0.62.

[0077] In some embodiments, the combined focal length f12 of the first lens and the second lens and the effective focal length f of the optical lens satisfy: 0.8<f12 / f<1.4. Satisfying the above range is beneficial for the system to have a longer focal length and meet the telephoto characteristic. More specifically: 0.88<f12 / f<1.31.

[0078] In some embodiments, the combined focal length f345678 of the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens and the effective focal length f of the optical lens satisfy: -11<f345678 / f<-1.2. Satisfying the above range can reduce the difficulty of aberration correction of the lenses, and improve the imaging quality of the optical lens. More specifically: -10.78<f345678 / f<-1.25.

[0079] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -1.5<f3 / f4<-0.9. Satisfying the above range can effectively improve the aberration of the edge field of view and enhance the overall imaging quality of the optical lens. More specifically: -1.35<f3 / f4<-0.99.

[0080] In some embodiments, the optical lens satisfies the following conditional expressions: 20mm<f<22mm; 30°<FOV<32°; 12mm<EPD<13mm; 36mm<TTL<41mm; 1.5<Fno<1.8; 12mm<IH<12.5mm; 21°<CRA<26°; 3mm<BFL<4mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field angle of the optical lens, CRA represents the chief ray incident angle at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Satisfying the above range, the optical lens has at least one or more advantages such as telephoto, large aperture, and high imaging quality. More specifically: 20.96mm<f<21.57mm; 31.1°<FOV<31.3°; 12.32mm<EPD<12.69mm; 36.9mm<TTL<40.57mm; 1.65<Fno<1.75; 12mm<IH<12.2mm; 21.36°<CRA<25.11°; 3.22mm<BFL<3.71mm.

[0081] In some embodiments, the material of the lenses in the optical lens provided by the present invention can be glass or plastic. When the material of the lens is plastic, the production cost can be effectively reduced. In addition, when the material of the lens is glass, the geometric chromatic aberration of the optical system can be effectively corrected by virtue of the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt an all-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0082] 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 be 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, the second lens, and the eighth lens of the present invention adopt aspherical lenses, and the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens adopt spherical lenses.

[0083] In various embodiments of the present invention, when an aspherical lens is used, the shapes of each aspherical surface of the optical lens satisfy the following equations:

[0084]

[0085] 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, and F are the fourth, sixth, eighth, tenth, and twelfth order surface coefficients, respectively.

[0086] 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.

[0087] Example 1

[0088] 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, an aperture ST, 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, a filter G1, and a protective glass G2.

[0089] Among them, the first lens L1 has negative optical power, its object side S1 is concave, and its image side S2 is convex.

[0090] The second lens L2 has positive optical power, its object side S3 is convex, and its image side S4 is convex.

[0091] The third lens L3 has negative optical power, its object side S5 is concave, and its image side S6 is concave.

[0092] The fourth lens L4 has positive optical power, its object side S6 is convex, and its image side S7 is convex.

[0093] The third lens L3 and the fourth lens L4 form a cemented lens group, that is, the cemented surface of the image side of the third lens L3 and the object side of the fourth lens L4 is S6.

[0094] The fifth lens L5 has positive optical power, its object side S8 is convex, and its image side S9 is convex.

[0095] The sixth lens L6 has negative optical power, its object side S10 is concave, and its image side S11 is convex.

[0096] The seventh lens L7 has negative optical power, its object side S12 is concave, and its image side S13 is concave.

[0097] The eighth lens L8 has negative optical power, its object side S14 is concave, and its image side S15 is convex.

[0098] The object-side surface S16 and the image-side surface S17 of filter G1 are both planar.

[0099] The object side S18 and image side S19 of the protective glass G2 are both flat.

[0100] The imaging plane S20 is a plane.

[0101] The first lens L1, the second lens L2, and the eighth lens L8 are glass aspherical lenses, while the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are glass spherical lenses.

[0102] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0103] Table 1-1

[0104]

[0105] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0106] Table 1-2

[0107] S1 -3.85E+00 3.49E-05 -3.55E-06 8.62E-08 -8.63E-10 3.05E-12 S2 -6.25E+00 -3.22E-05 4.04E-07 -1.44E-08 4.11E-10 -3.16E-12 S3 -5.50E-01 -3.92E-04 6.76E-06 -8.95E-08 7.31E-10 -1.73E-12 S4 -3.53E+00 -5.63E-05 2.13E-06 -3.01E-08 2.51E-10 7.23E-13 S14 5.01E+00 -1.20E-03 1.38E-05 -2.07E-07 1.06E-08 -1.69E-10 S15 -4.33E+01 -9.74E-04 1.64E-05 -1.73E-07 5.49E-09 -7.76E-11

[0108] In this embodiment, the MTF curve of the optical lens 100 is as follows: Figure 2 As shown.

[0109] Figure 2 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents MTF value. As can be seen from the figure, the MTF value of this example is above 0.4 throughout the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, exhibiting good imaging quality and good detail resolution at both low and high frequencies.

[0110] Example 2

[0111] Please see Figure 3The 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 S5 of the third lens L3 is a convex surface; the object side surface S8 of the fifth lens L5 is a concave surface; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0112] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0113] Table 2-1

[0114]

[0115]

[0116] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0117] Table 2-2

[0118] S1 -3.45E+00 1.38E-05 -3.44E-06 8.86E-08 -8.29E-10 2.53E-12 S2 -5.18E+00 -5.18E-05 6.56E-07 -1.22E-08 3.90E-10 -3.09E-12 S3 -4.79E-01 -3.76E-04 6.80E-06 -8.92E-08 7.51E-10 -2.14E-12 S4 -3.23E+01 -4.73E-05 2.29E-06 -3.06E-08 3.00E-10 4.96E-13 S14 2.31E+00 -1.29E-03 3.20E-05 -5.44E-07 3.60E-09 5.95E-11 S15 -3.37E+01 -1.20E-03 3.19E-05 -6.79E-07 8.99E-09 -4.35E-11

[0119] In this embodiment, the MTF curve of the optical lens 200 is as follows: Figure 4 As shown. From Figure 4 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0120] Example 3

[0121] Please see Figure 5 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 object side surface S5 of the third lens L3 is a convex surface; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0122] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0123] Table 3-1

[0124]

[0125]

[0126] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0127] Table 3-2

[0128] S1 -3.16E+00 -9.06E-06 -3.50E-06 8.51E-08 -6.70E-10 1.40E-12 S2 -4.43E+00 -8.09E-05 4.99E-07 -6.95E-09 3.32E-10 -2.65E-12 S3 -5.74E-01 -3.71E-04 6.55E-06 -9.00E-08 7.87E-10 -2.61E-12 S4 -3.42E+01 -2.80E-05 1.51E-06 -2.90E-08 4.71E-10 -1.90E-12 S14 -1.96E-01 -1.13E-03 1.08E-06 8.99E-07 -4.15E-08 7.11E-10 S15 -4.99E+01 -7.24E-04 6.94E-06 5.29E-07 -2.18E-08 3.06E-10

[0129] In this embodiment, the MTF curve of the optical lens 300 is as follows: Figure 6 As shown. From Figure 6 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0130] Example 4

[0131] Please see Figure 7 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 object side S5 of the third lens L3 is a convex surface; the image side S15 of the eighth lens L8 is a concave surface; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0132] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0133] Table 4-1

[0134]

[0135]

[0136] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0137] Table 4-2

[0138] S1 -4.44E+00 -2.76E-05 -2.66E-06 1.07E-07 -1.41E-09 6.56E-12 S2 -8.25E+00 -1.35E-04 1.79E-06 -2.61E-09 9.08E-11 -1.56E-12 S3 -4.56E-01 -3.87E-04 6.52E-06 -9.42E-08 9.63E-10 -4.59E-12 S4 -5.00E+01 -2.75E-05 8.49E-07 -1.02E-08 2.19E-10 -9.83E-13 S14 1.26E+00 -8.76E-04 1.73E-06 8.71E-07 -3.93E-08 6.05E-10 S15 1.54E+01 -7.41E-04 3.86E-06 4.53E-07 -1.91E-08 1.90E-10

[0139] In this embodiment, the MTF curve of the optical lens 400 is as follows: Figure 8 As shown. From Figure 8 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0140] Example 5

[0141] Please see Figure 9The figure shows a schematic diagram 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 object side surface S8 of the fifth lens L5 is concave; the image side surface S11 of the sixth lens L6 is concave; 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] The surface profile parameters of the aspherical lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0146] Table 5-2

[0147] S1 -3.21E+00 -7.91E-05 -2.92E-06 9.52E-08 -9.46E-10 2.79E-12 S2 -4.45E+00 -1.35E-04 9.37E-07 -3.29E-09 2.25E-10 -2.34E-12 S3 -3.66E-01 -3.33E-04 6.08E-06 -8.87E-08 8.83E-10 -3.75E-12 S4 -2.67E+01 -3.85E-05 2.52E-06 -2.79E-08 3.78E-10 -1.13E-12 S14 1.01E+01 -1.26E-03 4.17E-06 5.91E-07 -2.28E-08 4.42E-10 S15 -3.54E+01 -1.02E-03 8.91E-06 3.25E-07 -1.18E-08 1.64E-10

[0148] In this embodiment, the MTF curve of the optical lens 500 is as follows: Figure 10 As shown. From Figure 10 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0149] Example 6

[0150] Please see Figure 11 The figure shown is a schematic diagram of the structure of the optical lens 600 provided in Embodiment 6 of the present invention. The main difference between this embodiment and Embodiment 1 is that: the object side surface S5 of the third lens L3 is a convex surface; the object side surface S8 of the fifth lens L5 is a concave surface; the image side surface S11 of the sixth lens L6 is a concave surface; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0151] The relevant parameters of each lens in the optical lens 600 in Example 6 are shown in Table 6-1.

[0152] Table 6-1

[0153]

[0154] The surface profile parameters of the aspherical lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0155] Table 6-2

[0156] S1 -3.03E+00 -2.57E-05 -3.41E-06 9.51E-08 -8.88E-10 2.60E-12 S2 -4.25E+00 -9.70E-05 9.53E-07 -8.97E-09 3.10E-10 -2.61E-12 S3 -2.45E-01 -3.45E-04 6.27E-06 -9.07E-08 8.30E-10 -3.22E-12 S4 -5.00E+01 -6.19E-05 2.32E-06 -2.62E-08 2.78E-10 -8.05E-13 S14 -1.15E+00 -1.44E-03 1.50E-05 5.44E-07 -3.02E-08 4.91E-10 S15 -4.34E+01 -1.11E-03 2.02E-05 1.62E-07 -1.42E-08 2.15E-10

[0157] In this embodiment, the MTF curve of the optical lens 600 is as follows: Figure 12 As shown. From Figure 12 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0158] Example 7

[0159] Please see Figure 13 The figure shown is a schematic diagram of the structure of the optical lens 700 provided in Embodiment 7 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S8 of the fifth lens L5 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0160] The relevant parameters of each lens in the optical lens 700 in Example 7 are shown in Table 7-1.

[0161] Table 7-1

[0162]

[0163]

[0164] The surface profile parameters of the aspherical lens of the optical lens 700 in Example 7 are shown in Table 7-2.

[0165] Table 7-2

[0166] S1 -3.25E+00 -7.56E-05 -2.98E-06 9.63E-08 -8.85E-10 2.04E-12 S2 -4.35E+00 -1.34E-04 9.27E-07 -4.24E-09 3.17E-10 -3.17E-12 S3 -3.33E-01 -3.30E-04 6.17E-06 -8.89E-08 8.75E-10 -3.43E-12 S4 -2.66E+01 -4.14E-05 2.52E-06 -2.66E-08 2.94E-10 8.97E-13 S14 7.26E-01 -1.22E-03 3.21E-05 -6.12E-07 4.34E-09 4.04E-11 S15 -1.72E+01 -1.04E-03 3.19E-05 -6.90E-07 8.56E-09 -3.61E-11

[0167] In this embodiment, the MTF curve of the optical lens 700 is as follows: Figure 14 As shown. From Figure 14 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0168] Example 8

[0169] Please see Figure 15 The figure shows a schematic diagram of the structure of the optical lens 800 provided in Embodiment 8 of the present invention. The main difference between this embodiment and Embodiment 1 is that: the object side S5 of the third lens L3 is a convex surface; the object side S8 of the fifth lens L5 is a concave surface; the object side S14 of the eighth lens L8 is a convex surface and the image side S15 is a concave surface; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0170] The relevant parameters of each lens in the optical lens 800 in Example 8 are shown in Table 8-1.

[0171] Table 8-1

[0172]

[0173]

[0174] The surface profile parameters of the aspherical lens of the optical lens 800 in Example 8 are shown in Table 8-2.

[0175] Table 8-2

[0176] S1 -4.27E+00 -9.70E-05 2.33E-06 -1.49E-10 -4.44E-10 3.81E-12 S2 -6.00E+00 -4.12E-05 2.92E-06 -3.12E-08 1.33E-10 1.40E-13 S3 -1.35E-01 -3.49E-04 7.53E-06 -1.38E-07 1.41E-09 -5.86E-12 S4 7.67E+00 -1.75E-05 8.40E-07 -4.74E-09 8.07E-12 7.75E-13 S14 1.20E-01 -3.75E-04 -5.45E-06 4.93E-07 -1.76E-08 2.68E-10 S15 7.05E+00 -4.90E-04 -6.90E-06 3.95E-07 -1.22E-08 9.92E-11

[0177] In this embodiment, the MTF curve of the optical lens 800 is as follows: Figure 16 As shown. From Figure 16 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0178] Example 9

[0179] Please see Figure 17 The figure shown is a schematic diagram of the structure of the optical lens 900 provided in Embodiment 9 of the present invention. The main difference between this embodiment and Embodiment 1 is that: the object side S5 of the third lens L3 is a convex surface; the object side S8 of the fifth lens L5 is a concave surface; the image side S15 of the eighth lens L8 is a concave surface; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0180] The relevant parameters of each lens in the optical lens 900 in Example 9 are shown in Table 9-1.

[0181] Table 9-1

[0182]

[0183] The surface profile parameters of the aspherical lens of the optical lens 900 in Example 9 are shown in Table 9-2.

[0184] Table 9-2

[0185] S1 -2.89E+00 -7.80E-05 -2.62E-06 1.08E-07 -1.26E-09 4.35E-12 S2 -3.87E+00 -1.18E-04 1.15E-06 -2.43E-09 2.69E-10 -3.45E-12 S3 2.74E-02 -3.14E-04 5.76E-06 -9.47E-08 1.06E-09 -5.27E-12 S4 -3.79E+01 -5.38E-05 1.93E-06 -1.83E-08 2.07E-10 -2.01E-13 S14 8.16E+00 -9.00E-04 1.35E-05 3.39E-07 -2.35E-08 3.97E-10 S15 3.49E+01 -7.92E-04 1.56E-05 -1.70E-08 -7.32E-09 7.93E-11

[0186] In this embodiment, the MTF curve of the optical lens 900 is as follows: Figure 18 As shown. From Figure 18As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0187] Example 10

[0188] Please see Figure 19 The figure shown is a schematic diagram of the structure of the optical lens 1000 provided in Embodiment 10 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side S8 of the fifth lens L5 is concave; the object side S14 of the eighth lens L8 is convex and the image side S15 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0189] The relevant parameters of each lens in the optical lens 1000 in Example 10 are shown in Table 10-1.

[0190] Table 10-1

[0191]

[0192] The surface profile parameters of the aspherical lens of the optical lens 1000 in Example 10 are shown in Table 10-2.

[0193] Table 10-2

[0194] S1 -3.98E+00 -1.16E-04 2.14E-06 1.56E-09 -4.09E-10 3.30E-12 S2 -5.54E+00 -9.27E-05 3.04E-06 -3.17E-08 1.22E-10 9.65E-14 S3 -1.84E-01 -3.66E-04 8.07E-06 -1.37E-07 1.38E-09 -5.52E-12 S4 -1.51E+01 1.05E-05 2.67E-06 -4.17E-08 8.04E-10 -2.94E-12 S14 -9.91E+00 -4.22E-04 -4.44E-06 3.52E-07 -1.23E-08 1.90E-10 S15 6.72E+00 -5.10E-04 -5.15E-06 3.32E-07 -1.04E-08 1.02E-10

[0195] In this embodiment, the MTF curve of the optical lens 1000 is as follows: Figure 20 As shown. From Figure 20 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0196] Example 11

[0197] Please see Figure 21 The diagram shown is a structural schematic of the optical lens 1100 provided in Embodiment 11 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S8 of the fifth lens L5 is concave; the image side surface S15 of the eighth lens L8 is concave; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0198] The relevant parameters of each lens in the optical lens 1100 in Example 11 are shown in Table 11-1.

[0199] Table 11-1

[0200]

[0201]

[0202] The surface profile parameters of the aspherical lens of the optical lens 1100 in Example 11 are shown in Table 11-2.

[0203] Table 11-2

[0204] S1 -2.95E+00 -8.56E-05 -2.12E-06 1.03E-07 -1.33E-09 5.43E-12 S2 -3.93E+00 -1.25E-04 1.44E-06 4.71E-10 5.30E-11 -1.40E-12 S3 -5.06E-02 -3.44E-04 6.39E-06 -9.62E-08 9.29E-10 -3.81E-12 S4 -1.62E+01 -2.25E-05 2.43E-06 -2.37E-08 3.38E-10 4.69E-14 S14 -4.30E+00 -6.74E-04 6.72E-06 2.32E-07 -1.24E-08 1.89E-10 S15 3.24E+01 -5.46E-04 7.83E-06 3.24E-08 -3.43E-09 9.25E-12

[0205] In this embodiment, the MTF curve of the optical lens 1100 is as follows: Figure 22 As shown. From Figure 22 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0206] Please refer to Tables 12-1 and 12-2 for the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, principal ray incident angle CRA at maximum image height, true image height IH corresponding to the maximum field of view, maximum field of view FOV, entrance pupil diameter EPD, back focal length BFL, and the values ​​corresponding to each conditional expression in each embodiment.

[0207] Table 12-1

[0208]

[0209]

[0210] Table 12-2

[0211]

[0212]

[0213]

[0214] In summary, the optical lens provided by the present invention employs eight lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as telephoto, large aperture, and high imaging quality.

[0215] 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.

[0216] 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 comprising eight lenses with optical power, characterized in that, Along the optical axis from the object side to the imaging plane, the system sequentially includes: a first lens with negative optical power, whose object side surface is a concave surface and whose image side surface is a convex surface; a second lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; a third lens with negative optical power, whose image side surface is a concave surface; a fourth lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; a fifth lens with positive optical power, whose image side surface is a convex surface; a sixth lens with negative optical power, whose object side surface is a concave surface; a seventh lens with negative optical power, whose object side surface is a concave surface and whose image side surface is a concave surface; an eighth lens with negative optical power; wherein the combined focal length f56 of the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy: 1<f56 / f<18; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.6<TTL / f<2.

2. The optical lens according to claim 1, characterized in that, The combined focal length f56 of the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy: 1.05<f56 / f<16.95; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.72<TTL / f<1.93; the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 2.8<TTL / IH<3.

4.

3. The optical lens according to claim 1, characterized in that, The real image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens and the maximum field of view FOV of the optical lens satisfy: 0.99<(IH / 2) / (f×Tan(FOV / 2))<1.04; the clear aperture half-diameter d1 of the object side surface of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens and the maximum field of view FOV of the optical lens satisfy: 4<d1 / (IH / 2) / Tan(FOV / 2)<4.

8.

4. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.2<f1 / f<-1.4; the curvature radius R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: -0.4<R1 / f<-0.2; the curvature radius R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: -0.6<R2 / f<-0.

3.

5. The optical lens according to claim 1, characterized in that, The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 0.6<f2 / f<0.9; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.4<R3 / f<0.7; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: -5<R4 / f<-1.

2.

6. The optical lens according to claim 1, characterized in that, The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -0.8<f3 / f<-0.4; the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: -2.5<f8 / f<-0.

8.

7. The optical lens according to claim 1, characterized in that, A focal length f5 of the fifth lens and an effective focal length f of the optical lens satisfy: 0.75<f5 / f<1.5; and a focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -3.3<f6 / f<-1.

1.

8. The optical lens according to claim 1, characterized in that, A focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.1<f7 / f<-1; a radius of curvature R13 of an object-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: -2.7<R13 / f<-1.5; and a radius of curvature R14 of an image-side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.8<R14 / f<2.

9.

9. The optical lens according to claim 1, characterized in that, A combined focal length f12 of the first lens and the second lens and a combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens satisfy: 1<f12 / f1234<1.8; and a combined focal length f56 of the fifth lens and the sixth lens and a combined focal length f5678 of the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -24<f56 / f5678<-0.

3.

10. The optical lens according to claim 1, characterized in that, The optical lens satisfies at least one of the following conditional expressions: a radius of curvature R1 of an object-side surface of the first lens and a radius of curvature R2 of an image-side surface of the first lens satisfy: -0.3<(R1-R2) / (R1+R2)<-0.1; or a radius of curvature R3 of an object-side surface of the second lens and a radius of curvature R4 of an image-side surface of the second lens satisfy: -0.9<(R3+R4) / (R3-R4)<-0.4; or the radius of curvature R13 of the object-side surface of the seventh lens and the radius of curvature R14 of the image-side surface of the seventh lens satisfy: |(R13+R14) / (R13-R14)|<0.5.

Images