Optical lens

Abstract

The invention discloses an optical lens, which comprises six lenses which sequentially comprise a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an image side along an optical axis, the object side surface of the second lens is a convex surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the fourth lens has positive focal power, and the object side surface of the fourth lens is a convex surface; the fifth lens has negative focal power, and the image side surface of the fifth lens is a concave surface; and the sixth lens has positive focal power. The six lenses are adopted, and through specific surface shape arrangement and reasonable focal power distribution, the lens has at least one of the advantages of long focus, miniaturization, low cost, high resolution and normal use in weak light and severe environments.

Description

Technical Field

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

[0002] As people's requirements for driving experience continue to increase, automotive optical lenses are increasingly used in intelligent driving, and the status of automotive optical lenses in the automotive-related industries continues to improve.

[0003] Among the in-vehicle cameras, the front-view camera is the core component of ADAS (Advanced Driver Assistance System), which is mainly responsible for functions such as forward collision warning, lane departure warning and pedestrian detection. At present, the price of the front-view camera is usually much higher than that of other types of cameras due to the complex algorithms and chip processing involved, which also reflects the important position of the front-view camera in the in-vehicle camera system. With the rapid development of advanced driver assistance systems, the requirements for front-view lenses are getting higher and higher. Therefore, it is necessary to develop an optical lens with good imaging effect. Summary of the invention

[0004] To this end, an object of the present invention is to provide an optical lens having at least one of the advantages of long focal length, miniaturization, low cost, high resolution, and normal use in weak light and harsh environments.

[0005] The present invention provides an optical lens, which has a total of six lenses, and includes, from the object side to the imaging surface along the optical axis: a first lens with negative optical power, whose object side surface is a concave surface and the image side surface is a concave surface; a second lens with positive optical power, whose object side surface is a convex surface; a third lens with positive optical power, whose object side surface is a convex surface and the image side surface is a concave surface; a fourth lens with positive optical power, whose object side surface is a convex surface; a fifth lens with negative optical power, whose image side surface is a concave surface; and a sixth lens with positive optical power.

[0006] In some embodiments, a radius of curvature R1 of the object-side surface of the first lens and a radius of curvature R2 of the image-side surface of the first lens satisfy: 1.2<|(R1-R2) / (R1+R2)|.

[0007] In some embodiments, a radius of curvature R5 of the object-side surface and a radius of curvature R6 of the image-side surface of the third lens satisfy: -0.9<(R5-R6) / (R5+R6)<-0.2.

[0008] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5<TTL / f<2.5.

[0009] In some embodiments, the 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: 0.95<(IH / 2) / (f×Tan(FOV / 2))<1.1.

[0010] In some embodiments, the total optical length TTL of the optical lens, the 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: 45<180°×TTL / (IH / 2) / (FOV / 2)<80.

[0011] In some embodiments, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: f1 / f<-1.

[0012] In some embodiments, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.5<f3 / f.

[0013] In some embodiments, the radius of curvature R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.5<R3 / f<0.9.

[0014] In some embodiments, a radius of curvature R10 of the image-side surface of the fifth lens element and an effective focal length f of the optical lens satisfy: 0.2<R10 / f<0.6.

[0015] Compared with the prior art, the optical lens provided by the present invention uses six lenses with optical power, and has at least one of the advantages of long focus, miniaturization, low cost, high resolution, and normal use in weak light and harsh environments through specific surface shape settings and reasonable optical power distribution. In particular, the object side surface of the first lens is a concave surface and the image side surface is a concave surface, which can reduce the effective working aperture of the first lens and prevent the light from being too divergent, resulting in an excessively large aperture of the lens behind the optical lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0017] Figure 1 Schematic diagram of the structure of the optical lens of Example 1 of the present invention.

[0018] Figure 2 It is a field curvature curve diagram of the optical lens according to embodiment 1 of the present invention.

[0019] Figure 3 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 1 of the present invention.

[0020] Figure 4This is the MTF curve diagram of the optical lens in Example 1 of the present invention.

[0021] Figure 5 Schematic diagram of the structure of the optical lens of embodiment 2 of the present invention.

[0022] Figure 6 It is a field curvature curve diagram of the optical lens according to embodiment 2 of the present invention.

[0023] Figure 7 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 2 of the present invention.

[0024] Figure 8 This is an MTF curve diagram of the optical lens in Example 2 of the present invention.

[0025] Fig. 9 Schematic diagram of the structure of the optical lens of Example 3 of the present invention.

[0026] Fig.10 4 is a field curvature curve diagram of the optical lens according to embodiment 3 of the present invention.

[0027] Fig.11 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0028] Fig.12 This is the MTF curve diagram of the optical lens in Example 3 of the present invention.

[0029] Fig.13 Schematic diagram of the structure of the optical lens of Example 4 of the present invention.

[0030] Fig.14 4 is a field curvature curve diagram of the optical lens according to embodiment 4 of the present invention.

[0031] Fig.15 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 4 of the present invention.

[0032] Fig.16 This is the MTF curve diagram of the optical lens in Example 4 of the present invention.

[0033] Fig.17 Schematic diagram of the structure of the optical lens of Example 5 of the present invention.

[0034] Fig.18 It is a field curvature curve diagram of the optical lens according to embodiment 5 of the present invention.

[0035] Fig.19 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 5 of the present invention.

[0036] Fig. 20This is the MTF curve diagram of the optical lens in Example 5 of the present invention.

[0037] Fig.21 Schematic diagram of the structure of the optical lens of Example 6 of the present invention.

[0038] Fig. 22 It is a field curvature curve diagram of the optical lens according to Example 6 of the present invention.

[0039] Fig.23 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 6 of the present invention.

[0040] Fig.24 This is the MTF curve diagram of the optical lens in Example 6 of the present invention.

[0041] Fig.25 Schematic diagram of the structure of the optical lens of Example 7 of the present invention.

[0042] Fig.26 4 is a field curvature curve diagram of the optical lens according to embodiment 7 of the present invention.

[0043] Fig. 27 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 7 of the present invention.

[0044] Fig.28 This is an MTF curve diagram of the optical lens in Example 7 of the present invention.

[0045] Fig.29 Schematic diagram of the structure of the optical lens of Example 8 of the present invention.

[0046] Fig.30 It is a field curvature curve diagram of the optical lens according to Example 8 of the present invention.

[0047] Fig.31 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 8 of the present invention.

[0048] Fig.32 This is the MTF curve diagram of the optical lens in Example 8 of the present invention. DETAILED DESCRIPTION

[0049] In order to better understand the present invention, a more detailed description will be made of various aspects of the present invention with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of embodiments of the present invention, and are not intended to limit the scope of the present invention 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.

[0050] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0051] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0052] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface 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 position of the concave surface 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 object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0053] It should also be understood that the terms "comprises", "including", "having", "includes" 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. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present invention, "may" is used to mean "one or more embodiments of the present invention". And, the term "exemplary" is intended to refer to an example or illustration.

[0054] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0055] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0056] The present invention provides an optical lens having a total of six lenses. The optical lens comprises, in sequence from the object side to the imaging surface along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, and the optical centers of the lenses are located on the same straight line.

[0057] In some embodiments, the first lens is configured to have a negative optical focal length, which is beneficial to diverging light. Under the same field of view angle, the light emitted through the image side of the first lens can enable the subsequent optical system to have a larger light receiving surface and reduce the front port diameter; the object side surface is concave and the image side surface is concave, which can reduce the effective working aperture of the first lens and prevent the light from being too divergent, resulting in an excessively large aperture of the lens behind the optical lens.

[0058] In some embodiments, the second lens is configured to have a positive optical focal length, which is beneficial for converging light. When used in combination with a first lens having a negative optical focal length, the overall length of the optical lens can be reduced, and the converging effect on light can further reduce the diameter of the rear port. The object side surface is a convex surface, which can converge the light passing through the first lens and reduce the height of the light, thereby reducing the aperture of the optical lens while slowing down the turning trend of the light to make it a smooth transition. At the same time, it can balance various aberrations generated by the front lens and improve the overall imaging quality of the optical lens.

[0059] In some embodiments, the third lens is configured to have a positive focal length, which is conducive to receiving the light rays converged from the second lens, reducing the height of the light beam when incident on the object side of the fourth lens, and reducing the diameter of the object side of the fourth lens; the object side is convex, and the image side is concave, which can smoothly receive the light rays, so that the light rays emitted by the second lens can smoothly enter the rear optical system, reduce the generation of aberrations, and improve the imaging quality. The edge field light rays can be deflected toward the optical axis after passing through the second side of the third lens, which is conducive to reducing the diameter of the rear port of the system.

[0060] In some embodiments, the fourth lens is configured to have positive optical power, which is beneficial to focusing light. When combined with the fifth lens, it can effectively correct the aberration of the optical lens, improve imaging quality, and optimize optical properties such as distortion. The object side is convex, which can suppress the angle of the edge field of view incident on the imaging surface, effectively transmit more light beams to the imaging surface, and improve imaging quality.

[0061] In some embodiments, the fifth lens is configured to have a negative optical power, which is beneficial for diverging light, so that the subsequent optical system has a larger light receiving surface, and the optical performance can be improved. The various aberrations caused by the front lens can be effectively corrected, and the imaging quality of the optical lens can be improved; the image side surface is a concave surface, and the light of the central field of view and the edge field of view passing through the fifth lens can be adjusted, especially the angle of the edge field of view light incident on the imaging surface is adjusted so that the main light is emitted parallel to the imaging surface, thereby increasing the proportion of the edge field of view in the imaging picture, enhancing the imaging clarity of the edge field of view, and at the same time correcting various aberrations caused by the front lens, thereby improving the overall imaging quality of the optical lens.

[0062] In some embodiments, the sixth lens is configured to have positive focal length, which is beneficial for receiving the front light and improving the resolution. Furthermore, the fifth lens receives the light compressed by the front positive lens, reduces the light angle, and meets the CRA requirements; and can optimize spherical aberration and improve imaging quality.

[0063] In some embodiments, the aperture may be disposed between the first lens and the second lens. It is understood that the aperture may be used to limit the amount of light entering to change the brightness of the image. In addition, when the aperture is located between the first lens and the second lens, the aperture can reasonably distribute the functions of the first lens to the sixth lens. For example, the first lens can be used to receive light to a greater extent, and the second lens to the sixth lens can be used to correct the aberration, which is beneficial to balancing the structure of the entire optical system. In addition, when the aperture is located between the first lens and the second lens, it is convenient to correct the aperture aberration and balance the structure and focal length distribution of the front lens group and the rear lens group.

[0064] In some embodiments, the optical lens may further include a filter, which is disposed between the sixth lens and the imaging surface to filter out interference light and prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0065] In some embodiments, the effective focal length f of the optical lens satisfies: 13mm<f<17mm. Meeting the above range is conducive to making the optical lens have a telephoto characteristic, ensuring the telephoto effect of the optical lens, making the system have a larger magnification, and having better imaging quality for scenes in a farther field of view.

[0066] In some embodiments, the maximum field of view of the optical lens satisfies: 30°<FOV<40°. Meeting the above range is conducive to making the optical lens have a suitable field of view, and being able to clearly shoot distant targets.

[0067] In some embodiments, the aperture value FNO of the optical lens satisfies: 1.4<FNO<1.8. Meeting the above range is conducive to achieving a large aperture characteristic, and can ensure image clarity in a low-light environment or at night.

[0068] In some embodiments, the incident angle CRA of the principal ray of the maximum field angle of the optical lens on the image plane satisfies: 14°<CRA<21°. Meeting the above range can make the CRA of the optical lens and the CRA of the chip photosensitive element have a larger allowable error range, thereby improving the adaptability of the optical lens to the image sensor.

[0069] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5<TTL / f<2.5. Meeting the above range can effectively reduce the total length, ensure sufficient space to adjust the lens structure, and optimize the imaging effect of the optical lens.

[0070] In some embodiments, the 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: 0.95<(IH / 2) / (f×Tan(FOV / 2))<1.1. Meeting the above range can better control the distortion of the optical lens, have the characteristics of small distortion, and improve the resolution of the optical lens.

[0071] In some embodiments, the image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 0.58<IH / f<0.75. Meeting the above range can ensure matching of a chip with a large image plane, so that the optical lens has the characteristics of both telephoto and large image plane.

[0072] In some embodiments, the optical back focus BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.2<BFL / f<0.4. Meeting the above range can achieve a balance between good imaging quality and easy-to-assemble optical back focus length, which is beneficial to ensure the imaging quality of the optical lens while avoiding interference between the lens and other components, reducing the difficulty of the camera module assembly process, and improving the production yield.

[0073] In some embodiments, the total optical length TTL of the optical lens, the 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: 45<180°×TTL / (IH / 2) / (FOV / 2)<80. When the above range is met, the length of the optical lens can be limited under the same imaging area and the same field of view, thereby realizing miniaturization of the optical lens.

[0074] In some embodiments, the total optical length TTL of the optical lens and the sum of the center thicknesses of the first to sixth lenses along the optical axis ΣCT satisfy: 0.5<ΣCT / TTL<0.8. If the above range is met, the total length of the optical lens can be compressed, making the structure of the optical lens more compact.

[0075] In some embodiments, the semi-aperture d1 of the object side of the first lens, the image height IH corresponding to the maximum field angle of the optical lens, and the maximum field angle FOV of the optical lens satisfy: 3<d1 / (IH / 2) / Tan(FOV / 2)<4.8. When the above range is met, the front port diameter can be small while the optical lens has a suitable field angle and image height, which is conducive to the miniaturization of the optical lens.

[0076] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: f1 / f<-1. Meeting the above range allows a wide range of light to enter the optical lens, obtain more image information, and help control lens distortion and reduce field curvature, thereby improving the geometric accuracy of the imaging surface. Preferably, -2.7<f1 / f<-1.

[0077] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 0.8<f2 / f<1.8. When the above range is met, the light deflection angle can be reduced while converging the light, so that the light trend can transition smoothly, and at the same time, various aberrations generated by the front lens can be balanced, thereby improving the imaging quality of the optical lens.

[0078] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.5<f3 / f. Meeting the above range can reduce the light deflection angle to make the light transition smoothly, and at the same time balance various aberrations generated by the front lens, thereby improving the imaging quality of the optical lens. Preferably, 1.5<f3 / f<7.1.

[0079] 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<1.2. When the above range is met, the light emitted from the fourth lens can be converged and adjusted to slow down the turning trend and convergence degree of the light, so that the light transitions smoothly, and at the same time, various aberrations generated by the front lens can be balanced to improve the overall imaging quality of the optical lens.

[0080] 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<-0.1. Meeting the above range can increase the imaging area, and the combination of the fourth lens and the fifth lens can optimize the lens chromatic aberration and improve the imaging quality.

[0081] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1.2<f6 / f. Meeting the above range can optimize spherical aberration, improve imaging quality, and suppress the angle of the edge field of view incident on the imaging surface, effectively transmit more light beams to the imaging surface, and improve imaging quality. Preferably, 1.2<f6 / f<4.9.

[0082] In some embodiments, the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.5<R3 / f<0.9. If the above range is met, the convex surface can be directed toward the object side, focusing the edge field light and improving the edge field imaging quality.

[0083] In some embodiments, the curvature radius R7 of the object side surface of the fourth lens and the effective focal length f of the optical lens satisfy: 0.4<R7 / f<0.9. If the above range is met, the convex surface can be directed toward the object side, focusing the edge field light and improving the edge field imaging quality.

[0084] In some embodiments, the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.2<R10 / f<0.6. If the above range is met, the concave surface can be directed toward the image side, focusing the edge field angle light and improving the relative illumination of the optical lens.

[0085] 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 satisfy: 1.2<|(R1-R2) / (R1+R2)|. Meeting the above range is conducive to the smooth transition of light to the rear, collecting more light into the lens, achieving a small aperture and a short total length while improving the resolution. Preferably, 1.2<|(R1-R2) / (R1+R2)|<18.

[0086] 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 satisfy: -0.9<(R5-R6) / (R5+R6)<-0.2. Meeting the above range helps to control the trend of the edge field of view light beam to increase the image height, while reducing the off-axis aberration of the optical lens and helping to reduce field curvature.

[0087] In some embodiments, the curvature radius R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: R1 / f<-0.75. If the above range is met, the concave surface can be directed toward the object side, which plays a role in diverging light, and the light passing through the object side surface of the first lens can enable the subsequent lens to have a larger light receiving surface. Preferably, -6.8<R1 / f<-0.75.

[0088] In some embodiments, the curvature radius R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: 1<R2 / f. When the above range is met, the concave surface can be directed toward the image side, which has a divergent effect on the light, which is beneficial to increase the imaging area of ​​the lens and improve the imaging quality. Preferably, 1<R2 / f<9.5.

[0089] In some embodiments, the radius of curvature R5 of the object side of the third lens and the effective focal length f of the optical lens satisfy: 0.7<R5 / f<3.1. When the above range is met, the convex surface can be directed toward the object side, so that the light emitted by the second lens can smoothly enter the third lens, and more light can be collected, thereby improving the quality of image surface details, reducing the generation of aberrations, and improving image quality.

[0090] In some embodiments, the curvature radius R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: 2.3<R6 / f. When the above range is met, the concave surface can be directed toward the image side, so that the edge field light is deflected toward the optical axis after passing through the second side surface of the third lens, which is beneficial to reducing the diameter of the rear port of the system. Preferably, 2.3<R6 / f<8.

[0091] As an implementation mode, the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens can be made of all-glass lenses or a glass-plastic mixture, both of which can achieve good imaging effects. In the present application, in order to improve the imaging quality of the lens, each lens uses a glass lens. At the same time, at least one of the object side or image side of the second lens and the sixth lens is an aspherical surface. The characteristic of an aspherical lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration.

[0092] In order to make the system have better optical performance, multiple aspherical lenses are used in the lens, and the shape of each aspherical surface of the optical lens satisfies the following equation:

[0093]

[0094] Among them, 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 surface vertex, K is the quadratic surface coefficient, A, B, C, D, E, and F are the second-order, fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients respectively.

[0095] The present invention is further described below in multiple 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 table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0096] Example 1

[0097] See also Figure 1 , which is a schematic diagram of the structure of the optical lens provided in Embodiment 1 of the present invention, wherein the optical lens includes, in sequence from the object side to the imaging surface S14 along the optical axis: 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 and a filter G1.

[0098] Among them, the first lens L1 is a spherical lens with negative focal power, the object side surface S1 of the first lens is concave, and the image side surface S2 of the first lens is concave; the second lens L2 is an aspherical lens with positive focal power, the object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is concave; the third lens L3 is a spherical lens with positive focal power, the object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave; the fourth lens L4 is a spherical lens with positive focal power, the fourth lens The object side surface S7 is a concave surface, and the image side surface S9 of the fifth lens is a concave surface; the fifth lens L5 is a spherical lens with negative optical power, the object side surface S7 of the fifth lens is a concave surface, and the image side surface S9 of the fifth lens is a concave surface, and the fourth lens L4 and the fifth lens L5 form a cemented lens, and the cemented surface S8 is formed; the sixth lens L6 is an aspherical lens with positive optical power, the object side surface S10 of the sixth lens is a convex surface, and the image side surface S11 of the sixth lens is a convex surface; the object side surface S12 and the image side surface S13 of the filter G1 are both planes.

[0099] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 1-1.

[0100] Table 1-1

[0101]

[0102] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 1-2.

[0103] Table 1-2

[0104] Face number K A B C S3 -3.26E-01 0.00E+00 -4.86E-05 1.62E-06 S4 5.00E+01 0.00E+00 2.15E-04 -1.23E-06 S10 -2.70E+07 0.00E+00 -1.18E-03 -6.08E-05 S11 -1.37E+01 0.00E+00 -6.95E-04 -1.84E-05 Face number D E F S3 -6.60E-08 1.60E-09 -1.09E-11 S4 2.61E-07 -7.80E-09 1.34E-10 S10 3.98E-07 -1.56E-07 -4.49E-09 S11 -8.26E-07 4.36E-08 -5.00E-10

[0105] Figure 2 The field curvature curve of Example 1 is shown, which indicates the degree of curvature of light of different wavelengths on the meridional image plane and the sagittal image plane, with the horizontal axis indicating the offset (unit: mm) and the vertical axis indicating the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.2mm to 0.05mm, indicating that the optical lens can correct the field curvature well.

[0106] Figure 3The distortion curve of Example 1 is shown, which represents the F-Tan (Theta) distortion at different field angles on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the distortion value is controlled within the range of 0 to 4.5%, indicating that the optical lens has a small distortion, the image compression in the edge angle area is relatively gentle, and the clarity of the expanded image is effectively improved.

[0107] Figure 4 The modulation transfer function (MTF) curve of Example 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.2 in the whole field of view, and in the range of 0 to 120 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0108] Example 2

[0109] See also Figure 5 , shown is a schematic diagram of the structure of the optical lens provided in Example 2 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0110] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 2-1.

[0111] Table 2-1

[0112]

[0113]

[0114] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 2-2.

[0115] Table 2-2

[0116] Face number K A B C S3 1.21E+00 0.00E+00 -1.79E-04 2.01E-06 S4 -1.82E+00 0.00E+00 1.77E-04 2.27E-06 S10 -9.81E+39 0.00E+00 1.85E-03 -3.06E-05 S11 -2.91E+01 0.00E+00 1.55E-03 -3.50E-05 Face number D E F S3 -1.82E-07 5.47E-09 -7.98E-11 S4 -2.81E-08 2.15E-09 -5.77E-12 S10 6.80E-06 -4.17E-07 1.09E-08 S11 9.30E-06 -5.97E-07 1.56E-08

[0117] Figures 6 to 8The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 2 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.05mm to 0.1mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of 0 to 6%, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.3 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0118] Example 3

[0119] See also Fig. 9 , shown is a schematic diagram of the structure of the optical lens provided in Example 3 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0120] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 3-1.

[0121] Table 3-1

[0122]

[0123] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 3-2.

[0124] Table 3-2

[0125] Face number K A B C S3 1.43E+00 0.00E+00 -2.58E-04 7.82E-07 S4 -6.39E-01 0.00E+00 1.16E-04 1.03E-06 S10 -8.71E+03 0.00E+00 -2.95E-04 -6.55E-06 S11 -8.00E+01 0.00E+00 -2.35E-04 -4.36E-06 Face number D E F S3 -1.55E-07 3.88E-09 -6.34E-11 S4 -2.86E-08 1.26E-09 -1.06E-11 S10 -2.89E-06 1.10E-07 -5.87E-09 S11 -1.35E-06 2.46E-09 7.32E-10

[0126] Figures 10 to 12 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 3 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.05mm to 0.1mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of 0 to 4%, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.3 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0127] Example 4

[0128] See also Fig.13, shown is a schematic diagram of the structure of the optical lens provided in Example 4 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that the fourth lens has a negative optical focal length, and parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0129] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 4-1.

[0130] Table 4-1

[0131]

[0132] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 4-2.

[0133] Table 4-2

[0134] Face number K A B C S3 8.51E-01 0.00E+00 -3.25E-04 -3.68E-06 S4 -6.84E-01 0.00E+00 1.07E-04 -7.05E-07 S11 -4.05E+38 0.00E+00 -1.07E-03 -9.69E-05 S12 4.80E+00 0.00E+00 -4.66E-04 -1.10E-04 Face number D E F S3 -6.31E-08 -3.89E-10 -5.70E-11 S4 1.02E-07 -2.77E-09 4.70E-11 S11 -2.83E-06 5.04E-07 -4.45E-08 S12 5.81E-06 -3.41E-07 6.10E-09

[0135] Figures 14 to 16 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 4 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.05mm to 0.1mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of 0 to 2%, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.25 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0136] Example 5

[0137] See also Fig.17 , shown is a schematic diagram of the structure of the optical lens provided in Example 5 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0138] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 5-1.

[0139] Table 5-1

[0140]

[0141] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 5-2.

[0142] Table 5-2

[0143] Face number K A B C S3 -9.75E-01 0.00E+00 0.00E+00 3.31E-07 S4 5.00E+01 0.00E+00 0.00E+00 -2.65E-06 S11 1.14E+00 0.00E+00 -9.08E-04 -5.34E-05 S12 8.42E-02 0.00E+00 -5.30E-04 -2.88E-05 Face number D E F S3 -9.72E-08 2.34E-09 -3.92E-11 S4 3.87E-08 -1.17E-09 -4.13E-12 S11 3.24E-06 -2.14E-07 4.75E-09 S12 -1.85E-07 9.76E-09 3.70E-10

[0144] Figures 17 to 20 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 5 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.1mm to 0.05mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of -1.2% to 0, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.3 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0145] Example 6

[0146] See also Fig.21 , shown is a schematic diagram of the structure of the optical lens provided in Example 6 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0147] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 6-1.

[0148] Table 6-1

[0149]

[0150] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 6-2.

[0151] Table 6-2

[0152]

[0153]

[0154] Figure 22 to Figure 24 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 6 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.05mm to 0.05mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of -0.8% to 0, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.2 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0155] Example 7

[0156] See also Fig.25 , shown is a schematic diagram of the structure of the optical lens provided in Example 7 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0157] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 7-1.

[0158] Table 7-1

[0159]

[0160] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 7-2.

[0161] Table 7-2

[0162]

[0163]

[0164] Figure 26 to Figure 28 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 7 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.05mm to 0.05mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of -1% to 0, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.2 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0165] Example 8

[0166] See also Fig.29 , shown is a schematic diagram of the structure of the optical lens provided in Example 8 of the present invention. The optical lens of this embodiment is substantially the same as that of the above-mentioned Example 1, except that parameters such as the curvature radius of each lens surface, the thickness of each lens, and the aspheric coefficient of each lens are different.

[0167] Specifically, the design parameters of each lens of the optical lens provided in this embodiment are shown in Table 8-1.

[0168] Table 8-1

[0169]

[0170] The surface coefficients of the aspherical surfaces of the optical lens in this embodiment are shown in Table 8-2.

[0171] Table 8-2

[0172] Face number K A B C S3 -4.28E-01 0.00E+00 0.00E+00 -1.66E-06 S4 5.01E+01 0.00E+00 0.00E+00 5.76E-06 S11 5.66E+01 0.00E+00 -1.77E-03 2.43E-05 S12 -8.04E+01 0.00E+00 -2.22E-03 1.08E-04 Face number D E F S3 1.19E-07 -3.98E-09 4.51E-11 S4 -5.58E-07 1.96E-08 -3.16E-10 S11 -2.09E-05 1.71E-06 -8.42E-08 S12 -8.75E-06 3.32E-07 -4.85E-09

[0173] Figure 30 to Figure 32 The field curvature curve, distortion curve, and modulation transfer function (MTF) curve of Example 8 are shown respectively. It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.1mm to 0.1mm, indicating that the optical lens can well correct the field curvature; the distortion value is controlled within the range of 0 to 6%, indicating that the optical lens has a small distortion; the MTF value of the optical lens is above 0.2 in the whole field of view, and within the range of 0 to 120lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0174] Please refer to Table 9, which shows the optical characteristics corresponding to the optical lenses provided in the above 8 embodiments, including the effective focal length f of the optical lens, the maximum field of view FOV, the pupil diameter EPD, the total optical length TTL, the aperture value FNO, the image height IH corresponding to the maximum field of view angle, the main ray incident angle CRA, the optical back focus BFL and the numerical value corresponding to each conditional expression in each embodiment.

[0175] Table 9

[0176]

[0177]

[0178] Table 9

[0179]

[0180]

[0181] To sum up, the optical lens in the embodiment of the present invention adopts six lenses with optical focal length. By reasonably allocating the optical focal length of each lens, reasonably matching the surface shape of each lens, reasonably setting the thickness of each lens and the distance between each lens, reasonably setting the position of the aperture, and setting the optical lens to have smaller distortion, it is possible to achieve a balance of telephoto (maximum f value is 15.09mm), large aperture (minimum FNO value is 1.60) and high pixels, thereby meeting the use requirements of vehicle-mounted lenses.

[0182] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0183] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, comprising six lenses, characterized in that: Along the optical axis from the object side to the imaging surface, it includes: The first lens has a negative optical power, and its object side surface is concave and its image side surface is concave; a second lens having positive refractive power and a convex object-side surface; The third lens has positive power, its object side surface is convex and its image side surface is concave; a fourth lens element having positive refractive power and a convex object-side surface; a fifth lens element having negative optical power, whose image side surface is concave; The sixth lens has positive refractive power.

2. The optical lens according to claim 1, characterized in that: A curvature radius R1 of the object side surface and a curvature radius R2 of the image side surface of the first lens satisfy: 1.2<|(R1-R2) / (R1+R2)|.

3. The optical lens according to claim 1, characterized in that: A curvature radius R5 of the object side surface and a curvature radius R6 of the image side surface of the third lens satisfy: -0.9<(R5-R6) / (R5+R6)<-0.

2.

4. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy the following conditions: 1.5<TTL / f<2.

5.

5. The optical lens according to claim 1, characterized in that: The 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 the following requirements: 0.95<(IH / 2) / (f×Tan(FOV / 2))<1.

1.

6. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens, the image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy the following conditions: 45<180°×TTL / (IH / 2) / (FOV / 2)<80.

7. The optical lens according to claim 1, characterized in that: The effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: f1 / f<-1.

8. The optical lens according to claim 1, characterized in that: The effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy the following: 1.5<f3 / f.

9. The optical lens according to claim 1, characterized in that: The curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy the following: 0.5<R3 / f<0.

9.

10. The optical lens according to claim 1, characterized in that: The curvature radius R10 of the image-side surface of the fifth lens and the effective focal length f of the optical lens satisfy the following: 0.2<R10 / f<0.6.

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