Optical lens

Abstract

The application provides an optical lens, which comprises eight lenses in sequence along an optical axis from an object side to an imaging surface, and the eight lenses comprise: a first lens with negative optical power, wherein the object side surface of the first lens is a concave surface, and the image side surface of the first lens is a convex surface; a second lens with positive optical power, wherein the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a convex surface; a third lens with positive optical power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; a fourth lens with negative optical power, wherein the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; a sixth lens with negative optical power, wherein the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; a seventh lens with positive optical power, wherein the object side surface of the seventh lens is a convex surface; and an eighth lens with negative optical power, wherein the image side surface of the eighth lens is a concave surface. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration and improve the imaging quality of the optical lens.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, and particularly to an optical lens. BACKGROUND

[0002] With the increasing demand for driving experience, vehicle application type optical lenses are increasingly used in intelligent driving, and the status of vehicle optical lenses in the automotive industry is continuously improving.

[0003] Advanced Driver Assistance System (ADAS) plays an important role in intelligent driving, which collects environmental information through various lenses combined with sensors to ensure the safety of drivers. In addition to the requirements of optical lenses for the existing ADAS system, such as light and thin shape, high pixel, high resolution and other characteristics, the optical lens is also required to clearly image under low illumination conditions, so it is necessary to develop an optical lens with good imaging effect. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide an optical lens with excellent imaging quality.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is:

[0006] An optical lens, a total of eight lenses, including in order along the optical axis from the object side to the imaging surface:

[0007] The first lens with negative focal power, the object side surface is concave, and the image side surface is convex;

[0008] The second lens with positive focal power, the object side surface is convex, and the image side surface is convex;

[0009] The third lens with positive focal power, the object side surface is convex, and the image side surface is convex;

[0010] The fourth lens with negative focal power, the object side surface is concave, and the image side surface is convex;

[0011] The fifth lens with positive focal power, the object side surface is convex, and the image side surface is convex;

[0012] The sixth lens with negative focal power, the object side surface is concave, and the image side surface is concave;

[0013] The seventh lens with positive focal power, the object side surface is convex;

[0014] The eighth lens with negative focal power, the image side surface is concave;

[0015] The image-side surface curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: 0.6 < R12 / f < 3.

[0016] Further preferably, the combined focal length f34 of the third lens and the fourth lens and the effective focal length f of the optical lens satisfy: 2 < f34 / f < 6.5.

[0017] Further preferably, the object-side surface curvature radius R11 of the sixth lens and the image-side surface curvature radius R12 of the sixth lens satisfy: -3.5 < R11 / R12 < -0.4.

[0018] Further preferably, the object-side surface curvature radius R13 of the seventh lens and the image-side surface curvature radius R14 of the seventh lens satisfy: -2 < (R13+R14) / (R13-R14) < -0.7.

[0019] Further preferably, the focal length f1 of the first lens and the focal length f8 of the eighth lens satisfy: 1.5 < f1 / f8 < 2.6.

[0020] Further preferably, the back focal length BFL of the optical lens and the total track length TTL of the optical lens satisfy: 0.12 < BFL / TTL < 0.16.

[0021] Further preferably, the object-side half-hght semi-diameter SAG61 of the sixth lens, the image-side half-hght semi-diameter SAG62 of the sixth lens and the central thickness CT6 of the sixth lens satisfy: 0.5 < (SAG62-SAG61) / CT6 < 2.3.

[0022] Further preferably, the image-side half-hght semi-diameter SAG42 of the fourth lens and the image-side half-hght semi-diameter DM42 of the fourth lens satisfy: -0.04 < SAG42 / DM42 < -0.02.

[0023] Further preferably, the total track length TTL of the optical lens and the maximum diameter Dmax of all lenses in the optical lens satisfy: 4.5 < TTL / Dmax < 5.6.

[0024] Further preferably, the real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens and the radian value θ of the maximum half field angle of the optical lens satisfy: 1 < (IH / 2) / (f x θ) < 1.03.

[0025] The optical lens provided by the application adopts eight lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens is improved, the aberration is reduced, and the imaging quality of the optical lens is improved, so that the lens has one or more advantages of large aperture, long focus, low distortion, high pixel, high imaging quality and the like. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0027] Figure 1 It is a structure schematic diagram of the optical lens in the embodiment 1 of the present application.

[0028] Figure 2 It is a field curvature curve of the optical lens in the embodiment 1 of the present application.

[0029] Figure 3 It is an F-Tan(Theta) distortion curve of the optical lens in the embodiment 1 of the present application.

[0030] Figure 4 It is an axial aberration curve of the optical lens in the embodiment 1 of the present application.

[0031] Figure 5 It is a sagittal color aberration curve of the optical lens in the embodiment 1 of the present application.

[0032] Figure 6 It is an MTF curve of the optical lens in the embodiment 1 of the present application.

[0033] Figure 7 It is a structure schematic diagram of the optical lens in the embodiment 2 of the present application.

[0034] Figure 8 It is a field curvature curve of the optical lens in the embodiment 2 of the present application.

[0035] Figure 9 It is an F-Tan(Theta) distortion curve of the optical lens in the embodiment 2 of the present application.

[0036] Figure 10 It is an axial aberration curve of the optical lens in the embodiment 2 of the present application.

[0037] Figure 11 It is a sagittal color aberration curve of the optical lens in the embodiment 2 of the present application.

[0038] Figure 12 It is an MTF curve of the optical lens in the embodiment 2 of the present application.

[0039] Figure 13 It is a structure schematic diagram of the optical lens in the embodiment 3 of the present application.

[0040] Figure 14 Field curvature curve of the optical lens in embodiment 3 of the present application.

[0041] Figure 15 F-Tan(Theta) distortion curve of the optical lens in embodiment 3 of the present application.

[0042] Figure 16 Axial aberration curve of the optical lens in embodiment 3 of the present application.

[0043] Figure 17 Vignetting curve of the optical lens in embodiment 3 of the present application.

[0044] Figure 18 MTF curve of the optical lens in embodiment 3 of the present application.

[0045] Figure 19 Structure diagram of the optical lens in embodiment 4 of the present application.

[0046] Figure 20 Field curvature curve of the optical lens in embodiment 4 of the present application.

[0047] Figure 21 F-Tan(Theta) distortion curve of the optical lens in embodiment 4 of the present application.

[0048] Figure 22 Axial aberration curve of the optical lens in embodiment 4 of the present application.

[0049] Figure 23 Vignetting curve of the optical lens in embodiment 4 of the present application.

[0050] Figure 24 MTF curve of the optical lens in embodiment 4 of the present application.

[0051] Figure 25 Structure diagram of the optical lens in embodiment 5 of the present application.

[0052] Figure 26 Field curvature curve of the optical lens in embodiment 5 of the present application.

[0053] Figure 27 F-Tan(Theta) distortion curve of the optical lens in embodiment 5 of the present application.

[0054] Figure 28 Axial aberration curve of the optical lens in embodiment 5 of the present application.

[0055] Figure 29 Vignetting curve of the optical lens in embodiment 5 of the present application.

[0056] Figure 30 MTF curve of the optical lens in Embodiment 5 of the present application.

[0057] Figure 31 schematic structural diagram of the optical lens in Embodiment 6 of the present application.

[0058] Figure 32 field curvature curve of the optical lens in Embodiment 6 of the present application.

[0059] Figure 33 F-Tan(Theta) distortion curve of the optical lens in Embodiment 6 of the present application.

[0060] Figure 34 axial aberration curve of the optical lens in Embodiment 6 of the present application.

[0061] Figure 35 lateral chromatic aberration curve of the optical lens in Embodiment 6 of the present application.

[0062] Figure 36 MTF curve of the optical lens in Embodiment 6 of the present application.

[0063] Figure 37 schematic structural diagram of the optical lens in Embodiment 7 of the present application.

[0064] Figure 38 field curvature curve of the optical lens in Embodiment 7 of the present application.

[0065] Figure 39 F-Tan(Theta) distortion curve of the optical lens in Embodiment 7 of the present application.

[0066] Figure 40 axial aberration curve of the optical lens in Embodiment 7 of the present application.

[0067] Figure 41 lateral chromatic aberration curve of the optical lens in Embodiment 7 of the present application.

[0068] Figure 42 MTF curve of the optical lens in Embodiment 7 of the present application.

[0069] The following detailed description will further describe the present application in combination with the above-mentioned drawings. DETAILED DESCRIPTION

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] The optical lens of this invention comprises eight lenses, arranged sequentially along the optical axis from the object side to the imaging plane: first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, and eighth lens.

[0078] In some embodiments, the first lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The second lens may have positive optical power, with a convex object-side surface and a convex image-side surface. The third lens may have positive optical power, with a convex object-side surface and a convex image-side surface. The fourth lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The fifth lens may have positive optical power, with 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 concave image-side surface. The seventh lens may have positive optical power, with a convex object-side surface and an image-side surface that may be either concave or convex. The eighth lens may have negative optical power, with an object-side surface that may be either concave or convex, and an image-side surface that is concave.

[0079] In some embodiments, the optical lens may further 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 to change the brightness of the image. When the aperture stop is located between the first lens and the second lens, it facilitates the correction of aperture aberrations.

[0080] 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 affecting the lens's imaging performance.

[0081] In some embodiments, the third lens and the fourth lens can be cemented together to form a cemented lens, which can effectively correct chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberrations 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.

[0082] In some embodiments, the fifth lens and the sixth lens can be cemented together 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 aberrations 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.

[0083] In some embodiments, the radius of curvature R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.6 < R12 / f < 3. Meeting the above range can make the sixth lens have an appropriate surface shape, which is beneficial to balancing the astigmatism and field curvature of the optical lens and improving the imaging quality of the optical lens.

[0084] In some embodiments, the combined focal length f34 of the third lens and the fourth lens and the effective focal length f of the optical lens satisfy: 2 < f34 / f < 6.5. Meeting the above range and reasonably setting the combined focal length of the third and fourth lenses is beneficial to controlling the light trend, can continue to gently converge the light rays emitted from the second lens, compress the light height of the image side surface of the fourth lens when exiting, reduce the lens aperture, and is beneficial to the miniaturization of the lens.

[0085] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -3.5 < R11 / R12 < -0.4. The shape of the sixth lens is concave-concave. Meeting the above conditions enables the converging light rays with a large front-end aperture to have a smooth transition, helps to balance various aberrations, and at the same time reduces the lens sensitivity to a certain extent.

[0086] In some embodiments, 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: -2 < (R13 + R14) / (R13 - R14) < -0.7. Meeting the above range is beneficial to increasing the area of light entering the imaging surface, achieving large target surface imaging of the lens, and improving the imaging quality of the optical lens.

[0087] In some embodiments, the focal length f1 of the first lens and the focal length f8 of the eighth lens satisfy: 1.5 < f1 / f8 < 2.6. Meeting the above range, by reasonably setting the focal length ratio of the first and last lenses, the lens can have a smaller head size while having a larger imaging surface, and can better meet the balance of miniaturization and high pixels.

[0088] In some embodiments, the back focal length BFL of the optical lens and the total optical length TTL of the optical lens satisfy: 0.12 < BFL / TTL < 0.16. Meeting the above range is beneficial to achieving a balance between obtaining good imaging quality and easy assembly, ensuring the imaging quality of the optical lens while avoiding interference between the lens and other components, and reducing the assembly process difficulty of the camera module.

[0089] In some embodiments, the sagittal height SAG61 of the clear aperture on the object side of the sixth lens, the sagittal height SAG62 of the clear aperture on the image side of the sixth lens, and the central thickness CT6 of the sixth lens satisfy: 0.5 < (SAG62 - SAG61) / CT6 < 2.3. Meeting the above conditions can control the surface shape of the object side of the sixth lens, which is beneficial to the manufacturing and molding of the sixth lens, and reduces the defective rate. In addition, it can also prevent the surface shape from being too curved and complex, making the system field curvature tend to be balanced.

[0090] In some embodiments, the sagittal height SAG42 of the clear aperture on the image side of the fourth lens and the clear aperture diameter DM42 on the image side of the fourth lens satisfy: -0.04 < SAG42 / DM42 < -0.02. Meeting the above conditions can limit the degree of central depression of the fourth lens and reduce the difficulty of aberration correction in the peripheral field of view.

[0091] In some embodiments, the total optical length TTL of the optical lens and the maximum aperture Dmax among all the lenses in the optical lens satisfy: 4.5 < TTL / Dmax < 5.6. Meeting the above range, by controlling the ratio of the total optical length of the optical lens to the maximum aperture among all the lenses to be small, the entire optical lens can be made more compact, realizing the miniaturization of the optical lens.

[0092] In some embodiments, the true image height IH corresponding to the maximum field angle of view of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field angle of view of the optical lens satisfy: 1 < (IH / 2) / (f×θ) < 1.03. Meeting the above conditions can better achieve small distortion and is more conducive to achieving high resolution.

[0093] 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 view of the optical lens satisfy: 3 < TTL / IH < 4. Meeting the above conditions can better achieve the miniaturization of the lens. At the same time, when ensuring the same total length of the lens, it has a larger image plane and can match a larger-sized imaging chip to achieve high-definition imaging.

[0094] 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 < -1.3. Meeting the above range can allow a large range of light to enter the optical lens, obtaining more picture information, and also helps to control lens distortion and reduce field curvature, improving the geometric accuracy of the imaging plane.

[0095] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.1 < f2 / f < 1.8. Meeting the above conditions can control the light path direction, provide a more reasonable light incident angle for the subsequent lenses, and reduce astigmatism and field curvature.

[0096] 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 < 1.1; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: -1.8 < f4 / f < -0.8. Meeting the above conditions, the third lens and the fourth lens are cemented to form a doublet lens. The third lens and the fourth lens may have opposite optical powers, so that various aberrations of the optical system are fully corrected. On the premise of a compact structure, the resolution can be improved and the optical performance such as distortion can be optimized.

[0097] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < f5 / f < 1.1; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.8 < f6 / f < -0.6. Meeting the above conditions, the fifth lens and the sixth lens are cemented to form a doublet lens. The fifth lens and the sixth lens may have opposite optical powers, so that various aberrations of the optical lens are fully corrected, the resolution can be improved, and high resolution can be achieved. At the same time, the use of the cemented part is beneficial to reducing the tolerance sensitivity of the lens to tilt / eccentricity, etc. during the assembly process, improving the resolution stability, and further enhancing the system performance.

[0098] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.5 < f7 / f < 3.3. Meeting the above conditions, the seventh lens has a positive optical power, which can further focus the light, optimize the imaging quality, and correct the remaining aberrations (such as distortion, chromatic aberration, etc.), thereby ensuring the imaging clarity and color reproduction.

[0099] In some embodiments, the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: -0.9 < f8 / f < -0.5. Meeting the above conditions, the effective focal length value of the eighth lens is small, and the light divergence effect is good, which can further increase the light passing amount while ensuring high imaging quality.

[0100] 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: -22 < f56 / f < 2.4. Meeting the above conditions helps more light enter the cemented lens smoothly and helps to improve the illuminance.

[0101] In some embodiments, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 16° < FOV / Fno < 30°. Meeting the above conditions is beneficial to increasing the light input amount of the lens and achieving high-definition imaging.

[0102] In some embodiments, 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: -1.1 < R3 / R4 < -0.3. By making the optical system satisfy the above relational expression, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side surface of the second lens and the radius of curvature of the image side surface of the second lens, control the shape of the second lens, comprehensively balance the spherical aberration, chromatic aberration and field curvature of the optical system, and reduce the risk of ghost imaging, improve the resolution ability of the optical system. At the same time, it is also beneficial to reduce the processing difficulty of the second lens.

[0103] In some embodiments, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: -2.8 < R5 / R6 < -1. Satisfying the above conditions, the third lens can balance the system field curvature and avoid deterioration of the edge image quality.

[0104] In some embodiments, 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: -0.55 < (R3 + R4) / (R3 - R4) < 0; the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: 0 < (R5 + R6) / (R5 - R6) < 0.5. Satisfying the above conditions, reasonably control the radius of curvature of the object side surface and the image side surface of the second and third lenses, thereby being beneficial to controlling the shapes of the second and third lenses, optimizing the aberration balance of the lens group, and improving the imaging quality.

[0105] In some embodiments, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: -1.5 < (R7 + R8) / (R7 - R8) < -1.2. Satisfying the above range can reduce the light deflection angle, make the light trend smoother; at the same time, it can correct coma and field curvature, improve the flatness of imaging, and improve the imaging quality of the optical lens.

[0106] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -0.4 < (R11 + R12) / (R11 - R12) < 0.6. Satisfying the above range, by reasonably controlling the shapes of the object side surface and the image side surface of the sixth lens, the image height can be increased to achieve high-definition imaging.

[0107] In some embodiments, the radius of curvature R15 of the object side surface of the eighth lens and the radius of curvature R16 of the image side surface of the eighth lens satisfy: -0.4 < (R15 + R16) / (R15 - R16) < 1.25. Satisfying the above range is beneficial to suppressing the angle of the edge field of view incident on the imaging surface, effectively transmitting more light beams to the imaging surface, and at the same time can balance the field curvature and spherical aberration of the optical lens, improving the imaging quality of the optical lens.

[0108] In some embodiments, the radius of curvature R8 of the image side surface of the fourth lens and the effective focal length f of the optical lens satisfy: -10 < R8 / f < -6. Meeting the above range defines that the fourth lens has an appropriate surface shape, which can diverge the light rays emitted by the third lens, making the light rays in the marginal field of view show an upward trend, facilitating the image points on the imaging surface to be away from the optical axis, so as to facilitate achieving the effect of matching with a large chip, obtaining a larger picture, effectively eliminating aberration, and improving the resolution ability of the optical lens.

[0109] In some embodiments, the radius of curvature R16 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.4 < R16 / f < 1.7. Meeting the above conditions is conducive to alleviating the degree of deflection of light rays passing through the lens and can well reduce aberration.

[0110] In some embodiments, the central thickness CT3 of the third lens and the central thickness CT4 of the fourth lens satisfy: 2.5 < CT3 / CT4 < 10. Meeting the above relational expression, the two match with each other, which helps to eliminate axial chromatic aberration. In addition, the thicker third lens can block marginal stray light and also improve the overall rigidity of the lens group, making it suitable for high-vibration environments (such as vehicle-mounted lenses).

[0111] In some embodiments, the central thickness CT5 of the fifth lens and the central thickness CT6 of the sixth lens satisfy: 3 < CT5 / CT6 < 5.7. Meeting the above conditions can reduce the sensitivity of system performance, while ensuring the lens processing performance and assembly stability, and improving the assembly yield.

[0112] In some embodiments, the overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis respectively satisfy: 0.62 < ∑CT / TTL < 0.75. Meeting the above conditions can effectively compress the overall length of the optical lens, while being conducive to the structural design and production process of the optical lens.

[0113] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the F-number Fno of the optical lens satisfy: 5mm < IH / Fno < 6.5mm. Meeting the above conditions can ensure that the optical lens has a large aperture while maintaining a large image plane of the optical lens, achieving the balance of a large image plane and a large aperture.

[0114] In some embodiments, the edge thickness ET5 of the fifth lens and the central thickness CT5 of the fifth lens satisfy: 0.3 < ET5 / CT5 < 0.65; the edge thickness ET6 of the sixth lens and the central thickness CT6 of the sixth lens satisfy: 1.5 < ET6 / CT6 < 3.3. For the fifth lens and the sixth lens meeting the above conditions, the curvature combination of the biconvex and biconcave lenses can reduce field curvature and ensure clear focus at both the center and the edge.

[0115] In some embodiments, the clear aperture radius DM11 of the object side of the first lens and the clear aperture radius DM82 of the image side of the eighth lens satisfy: 1.1 < DM11 / DM82 < 1.4. By satisfying the above conditions and reasonably setting the ratio of the apertures of the first and last lenses, the lens can have a smaller head size while having a larger imaging surface, better meeting the balance between miniaturization and high pixel count.

[0116] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 0.8 < IH / EPD < 1.2. By satisfying the above range, while the optical lens meets the requirement of a large imaging surface, it can also ensure sufficient image surface brightness in the edge field of view, preventing vignetting and thus improving the imaging quality.

[0117] In some embodiments, the Abbe number Vd3 of the third lens and the Abbe number Vd2 of the second lens satisfy: 9 < Vd3 - Vd2 < 18. When the above relationship is satisfied, it is beneficial to select appropriate lens materials, effectively correcting chromatic aberration, and thereby improving the imaging clarity and imaging quality of the optical system.

[0118] In some embodiments, the optical lens satisfies the conditional formula: 28mm < TTL < 34mm, 12mm < f < 16mm, 30° < FOV < 40°, 8mm < IH < 10mm, 1.4 < Fno ≤ 1.8, 12° < CRA < 23°, where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, IH represents the image height corresponding to the maximum field angle of the optical lens, Fno represents the aperture value of the optical lens, and CRA represents the principal ray incident angle at the maximum image height of the optical lens. By satisfying the above conditions, it shows that the optical lens provided by the embodiments of the present invention at least: has a telephoto characteristic, can ensure the telephoto effect of the optical lens, enable the system to have a large magnification ratio, and have good imaging quality for scenes within a relatively far field of view; has an appropriate field angle and can clearly capture distant targets; has a large imaging surface, is adapted to a large target surface sensor, and improves the imaging quality; has a large aperture, further increasing the light input of the lens, and can ensure image clarity even in low light environments or at night; has a small CRA (not greater than 23°), and a small CRA is beneficial to improving the matching degree between the lens and the telephoto SENSOR (imaging chip) and improving the imaging clarity.

[0119] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens is made of plastic, production costs can be effectively reduced. Conversely, when the lens is made of glass, the low dispersion characteristic of glass itself can effectively correct the geometric chromatic aberration of the optical system. The optical lens provided by the present invention can employ an all-glass lens structure, which can reduce dispersion, effectively correct chromatic aberration of the optical lens, and improve image quality.

[0120] In some embodiments, the first, second, third, fourth, fifth, sixth, seventh, and eighth lenses can be spherical or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number of lenses and their size, and better achieving lens miniaturization. More specifically, the first and second lenses of this invention are spherical or aspherical lenses; the seventh lens is an aspherical lens; and the third, fourth, fifth, sixth, and eighth lenses are spherical lenses.

[0121] 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:

[0122]

[0123] 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.

[0124] 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.

[0125] Example 1

[0126] Please see Figure 1 The figure shown is a schematic diagram of the structure of the optical lens provided in Embodiment 1 of the present invention. The optical lens includes, in sequence along the optical axis from the object side to the imaging plane: 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.

[0127] Among them, the first lens L1 has negative optical power, its object side S1 is concave, and its image side S2 is convex.

[0128] The second lens L2 has positive optical power, and its object side S3 is convex, and its image side S4 is convex.

[0129] The third lens L3 has positive optical power, and its object side S5 is convex, as is its image side.

[0130] The fourth lens L4 has negative optical power, its object side is concave, and its image side S7 is convex.

[0131] The third lens L3 and the fourth lens L4 form a cemented lens group with positive optical power, 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.

[0132] The fifth lens L5 has positive optical power, its object side S8 is convex, and its image side is convex.

[0133] The sixth lens L6 has negative optical power, its object side is concave, and its image side S10 is concave.

[0134] The fifth lens L5 and the sixth lens L6 form a cemented lens group with negative 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 S9.

[0135] The seventh lens L7 has positive optical power, its object side S11 is convex, and its image side S12 is convex.

[0136] The eighth lens L8 has negative optical power, its object side S13 is concave, and its image side S14 is concave.

[0137] The object-side surface S15 and the image-side surface S16 of filter G1 are both planar.

[0138] The object side S17 and image side S18 of the protective glass G2 are both flat.

[0139] The imaging plane S19 is a plane.

[0140] The first, second, third, fourth, fifth, sixth, and eighth lenses are glass spherical lenses, while the seventh lens is a glass aspherical lens.

[0141] The relevant parameters of each lens in the optical lens of Example 1 are shown in Table 1-1.

[0142] Table 1-1

[0143]

[0144] The surface profile parameters of the aspherical lens in Example 1 are shown in Table 1-2.

[0145] Table 1-2

[0146] Face number K B C D E F S11 7.5608E-01 -3.0423E-04 -1.8919E-06 -3.1955E-07 1.3434E-08 -4.0180E-10 S12 -2.3350E+01 -4.0869E-04 -2.8717E-06 2.9326E-07 -1.8779E-08 2.3687E-10

[0147] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown.

[0148] Figure 2 The field curvature curve of Example 1 is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.02 mm, indicating that the optical lens can effectively correct the field curvature.

[0149] Figure 3 The F-Tan (Theta) distortion curve for Example 1 is shown, representing the distortion of light at different image heights on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the distortion of the optical lens is controlled within -2% to 0, indicating that the optical lens can effectively correct distortion.

[0150] Figure 4 The diagram shows the axial aberration curves for Example 1, representing the aberrations of each wavelength along 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. The diagram shows that the axial aberration offset is controlled within ±0.01 mm, indicating that the optical lens can effectively correct axial aberrations.

[0151] Figure 5 The diagram shows the transverse chromatic aberration curves for Example 1, representing the chromatic aberration of each wavelength relative to the center wavelength (0.54 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the diagram, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±3 μm, indicating that the optical lens can effectively correct chromatic aberration.

[0152] Figure 6The 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 0.5 throughout the entire field of view. Within the range of 0–120 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.

[0153] Example 2

[0154] Please see Figure 7 The diagram shows a schematic of the optical lens provided in Embodiment 2 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the fifth lens L5 and the sixth lens L6 form a cemented lens group with positive optical power; the first lens L1 is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0155] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2-1.

[0156] Table 2-1

[0157]

[0158]

[0159] The surface profile parameters of the aspherical lens in Example 2 are shown in Table 2-2.

[0160] Table 2-2

[0161] Face number K B C D E F S1 7.3313E-03 -3.9334E-06 4.4407E-07 -3.1086E-09 -1.3363E-10 1.3958E-12 S2 -2.2749E+01 6.4706E-06 4.2662E-07 2.2408E-10 -2.2513E-10 3.1690E-12 S11 9.9999E+01 -4.3983E-04 2.7159E-06 -7.0689E-08 1.1850E-08 -2.7935E-10 S12 -4.2746E+01 -4.9126E-05 -8.4547E-06 8.3277E-07 -6.5601E-09 -2.3574E-10

[0162] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 As shown.

[0163] from Figure 8 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.04 mm, indicating that the optical lens can effectively correct the field curvature.

[0164] from Figure 9 As can be seen, the distortion of the optical lens is controlled within -2% to 0, indicating that the optical lens can effectively correct distortion.

[0165] from Figure 10 As can be seen, the axial aberration offset is controlled within ±0.01mm, indicating that the optical lens can effectively correct axial aberration.

[0166] from Figure 11 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2μm, indicating that the optical lens can effectively correct chromatic aberration.

[0167] from Figure 12 As can be seen, the MTF value of this embodiment is above 0.38 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0168] Example 3

[0169] Please see Figure 13 The figure shows a schematic diagram of the optical lens provided in Embodiment 3 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1. The main difference is that the fifth lens L5 and the sixth lens L6 form a cemented lens group with positive optical power; the first lens L1 is a glass aspherical lens; the image side S12 of the seventh lens L7 is concave; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0170] The relevant parameters of each lens in the optical lens of Example 3 are shown in Table 3-1.

[0171] Table 3-1

[0172]

[0173]

[0174] The surface profile parameters of the aspherical lens in Example 3 are shown in Table 3-2.

[0175] Table 3-2

[0176] Face number K B C D E F S1 9.6846E-01 1.3761E-05 1.6702E-07 2.5298E-08 -6.9820E-10 6.6466E-12 S2 5.3307E+00 -1.9213E-05 5.6052E-08 -9.4311E-10 3.5136E-11 -2.5690E-12 S11 -7.7098E-01 -7.2696E-05 -8.9494E-07 2.8018E-08 -4.3556E-09 6.7114E-11 S12 -7.2685E+00 1.4945E-04 1.2493E-06 1.0453E-08 -1.0763E-08 3.2152E-10

[0177] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 14 , Figure 15 , Figure 16 , Figure 17 , Figure 18 As shown.

[0178] from Figure 14As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.03 mm, indicating that the optical lens can effectively correct the field curvature.

[0179] from Figure 15 As can be seen, the distortion of the optical lens is controlled within -2% to 0, indicating that the optical lens can effectively correct distortion.

[0180] from Figure 16 As can be seen, the axial aberration offset is controlled within ±0.01mm, indicating that the optical lens can effectively correct axial aberration.

[0181] from Figure 17 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±3μm, indicating that the optical lens can effectively correct chromatic aberration.

[0182] from Figure 18 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 120 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.

[0183] Example 4

[0184] Please see Figure 19 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 4 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the first lens L1 is a glass aspherical lens; the object side surface S13 of the eighth lens L8 is a convex surface; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0185] The relevant parameters of each lens in the optical lens of Example 4 are shown in Table 4-1.

[0186] Table 4-1

[0187]

[0188]

[0189] The surface profile parameters of the aspherical lens in Example 4 are shown in Table 4-2.

[0190] Table 4-2

[0191] Face number K B C D E F S1 -5.2207E-01 3.3976E-05 1.0107E-06 -5.8307E-08 1.1395E-09 -6.9183E-12 S2 -4.0619E+01 1.0733E-05 2.8275E-07 1.2106E-08 -8.5007E-10 1.2889E-11 S11 2.8213E+00 -6.5234E-04 -1.1788E-05 -2.9897E-07 6.5168E-09 -4.4367E-10 S12 4.3381E+01 -2.0588E-05 -6.2304E-06 2.4480E-08 -2.8191E-09 1.3322E-10

[0192] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows:Figure 20 , Figure 21 , Figure 22 , Figure 23 , Figure 24 As shown.

[0193] from Figure 20 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.02 mm, indicating that the optical lens can effectively correct the field curvature.

[0194] from Figure 21 As can be seen, the distortion of the optical lens is controlled within 0-2%, indicating that the optical lens can effectively correct distortion.

[0195] from Figure 22 As can be seen, the axial aberration offset is controlled within ±0.01mm, indicating that the optical lens can effectively correct axial aberration.

[0196] from Figure 23 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2μm, indicating that the optical lens can effectively correct chromatic aberration.

[0197] from Figure 24 As can be seen, the MTF value of this embodiment is above 0.55 throughout the entire field of view. In the range of 0 to 120 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.

[0198] Example 5

[0199] Please see Figure 25 The figure shows a schematic diagram of the optical lens provided in Embodiment 5 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the first lens L1 is a glass aspherical lens; the second lens L2 is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0200] The relevant parameters of each lens in the optical lens of Example 5 are shown in Table 5-1.

[0201] Table 5-1

[0202]

[0203] The surface profile parameters of the aspherical lens in Example 5 are shown in Table 5-2.

[0204] Table 5-2

[0205]

[0206]

[0207] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 26 , Figure 27 , Figure 28 , Figure 29 , Figure 30 As shown.

[0208] from Figure 26 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.02 mm, indicating that the optical lens can effectively correct the field curvature.

[0209] from Figure 27 As can be seen, the distortion of the optical lens is controlled within -2% to 0, indicating that the optical lens can effectively correct distortion.

[0210] from Figure 28 As can be seen, the axial aberration offset is controlled within ±0.01mm, indicating that the optical lens can effectively correct axial aberration.

[0211] from Figure 29 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2μm, indicating that the optical lens can effectively correct chromatic aberration.

[0212] from Figure 30 As can be seen, the MTF value of this embodiment is above 0.6 throughout the entire field of view. In the range of 0 to 120 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.

[0213] Example 6

[0214] Please see Figure 31 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 6 of the present invention. The optical lens in this embodiment is generally the same as that in Embodiment 1, except that: the first lens L1 is a glass aspherical lens; the second lens L2 is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0215] The relevant parameters of each lens in the optical lens of Example 6 are shown in Table 6-1.

[0216] Table 6-1

[0217]

[0218]

[0219] The surface profile parameters of the aspherical lens in Example 6 are shown in Table 6-2.

[0220] Table 6-2

[0221] Face number K B C D E F S1 -1.2767E+00 1.0026E-04 2.0889E-06 -2.1729E-09 -1.1380E-09 1.4568E-11 S2 -3.1350E+01 1.0491E-04 4.1077E-06 1.4411E-08 -6.3436E-10 4.7664E-12 S3 -1.3387E+00 1.7094E-05 5.6148E-07 7.5785E-09 2.3977E-10 4.0062E-12 S4 5.9922E+00 -3.8807E-05 7.6346E-09 1.5647E-08 1.3849E-10 4.5749E-12 S11 -6.1224E+00 -1.6119E-04 -4.4945E-06 4.7082E-07 -5.4426E-10 3.7229E-10 S12 1.5582E+00 -1.1258E-04 2.8309E-06 2.2271E-07 1.8121E-08 2.9693E-10

[0222] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 32 , Figure 33 , Figure 34 , Figure 35 , Figure 36 As shown.

[0223] from Figure 32 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.02 mm, indicating that the optical lens can effectively correct the field curvature.

[0224] from Figure 33 As can be seen, the distortion of the optical lens is controlled within -4% to 0, indicating that the optical lens can effectively correct distortion.

[0225] from Figure 34 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0226] from Figure 35 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1μm, indicating that the optical lens can effectively correct chromatic aberration.

[0227] from Figure 36 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 120 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.

[0228] Example 7

[0229] Please see Figure 37 The figure shows a schematic diagram of the optical lens provided in Embodiment 7 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the first lens L1 is a glass aspherical lens; the second lens L2 is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0230] The relevant parameters of each lens in the optical lens of Example 7 are shown in Table 7-1.

[0231] Table 7-1

[0232]

[0233] The surface profile parameters of the aspherical lens in Example 7 are shown in Table 7-2.

[0234] Table 7-2

[0235] Face number K B C D E F S1 -1.1596E+00 8.9859E-05 1.5424E-06 -8.7241E-09 -3.7667E-10 4.3893E-12 S2 -2.8144E+01 8.4073E-05 3.0600E-06 8.4264E-10 -3.9986E-10 4.9646E-12 S3 -2.0681E+00 1.0892E-05 3.1651E-07 1.7063E-09 -1.5432E-11 2.7926E-12 S4 4.6161E+00 -2.4771E-05 -6.4672E-08 5.8815E-09 -2.8340E-11 2.7064E-12 S11 -8.5584E+00 -2.1032E-04 -8.3546E-06 1.4676E-07 -2.3262E-09 2.6921E-10 S12 2.9996E+00 -1.0124E-04 -2.1675E-06 3.5898E-08 9.2394E-09 5.0177E-11

[0236] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens are respectively as follows: Figure 38 , Figure 39 , Figure 40 , Figure 41 , Figure 42 As shown.

[0237] from Figure 38 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.03 mm, indicating that the optical lens can effectively correct the field curvature.

[0238] from Figure 39 As can be seen, the distortion of the optical lens is controlled within -4% to 0, indicating that the optical lens can effectively correct distortion.

[0239] from Figure 40 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0240] from Figure 41 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1μm, indicating that the optical lens can effectively correct chromatic aberration.

[0241] from Figure 42 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 120 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.

[0242] Please refer to Table 8 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.

[0243] Table 8

[0244]

[0245]

[0246] 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 large aperture, long focal length, low distortion, high pixel count, and high imaging quality.

[0247] 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.

[0248] 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, eight pieces of lenses in total, characterized in that, In order from the object side to the imaging surface along the optical axis, successively comprise: a first lens with negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a second lens with positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a third lens with positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fourth lens with negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a fifth lens with positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a sixth lens with negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a concave surface; a seventh lens with positive focal power, the object side surface of which is a convex surface; an eighth lens with negative focal power, the image side surface of which is a concave surface; wherein the image side surface curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: 0.6 < R12 / f < 3; the object side surface half radius sagittal height SAG61 of the sixth lens, the image side surface half radius sagittal height SAG62 of the sixth lens, and the central thickness CT6 of the sixth lens satisfy: 0.5 < (SAG62-SAG61) / CT6 < 2.

3.

2. The optical lens of claim 1, wherein, the combined focal length f34 of the third lens and the fourth lens and the effective focal length f of the optical lens satisfy: 2 < f34 / f < 6.

5.

3. The optical lens of claim 1, wherein, the object side surface curvature radius R11 of the sixth lens and the image side surface curvature radius R12 of the sixth lens satisfy: -3.5 < R11 / R12 < -0.

4.

4. The optical lens of claim 1, wherein, the object side surface curvature radius R13 of the seventh lens and the image side surface curvature radius R14 of the seventh lens satisfy: -2 < (R13+R14) / (R13-R14) < -0.

7.

5. The optical lens of claim 1, wherein, the focal length f1 of the first lens and the focal length f8 of the eighth lens satisfy: 1.5 < f1 / f8 < 2.

6.

6. The optical lens of claim 1, wherein, the back focal length BFL of the optical lens and the total optical length TTL of the optical lens satisfy: 0.12 < BFL / TTL < 0.

16.

7. The optical lens of claim 1, wherein, the object side surface curvature radius R15 of the eighth lens and the image side surface curvature radius R16 of the eighth lens satisfy: -0.4 < (R15+R16) / (R15-R16) < 1.

25.

8. The optical lens of claim 1, wherein, the image side surface half radius sagittal height SAG42 of the fourth lens and the image side surface half radius DM42 of the fourth lens satisfy: -0.04 < SAG42 / DM42 < -0.

02.

9. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the maximum diameter Dmax in all lenses in the optical lens satisfy: 4.5 < TTL / Dmax < 5.

6.

10. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field angle of the optical lens satisfy: 1 < (IH / 2) / (f×θ) < 1.03.

Images