An optical lens

Abstract

This utility model discloses an optical lens, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane; the first lens, the sixth lens, and the eighth lens are all negative power lenses, while the second lens, the third lens, the fourth lens, the fifth lens, and the seventh lens are all positive power lenses; the entrance pupil diameter ENPD of the optical lens satisfies the condition that ENPD / TTL > 0.2 with respect to the total optical length TTL of the optical lens. By adopting the above technical solution and rationally setting the number of lenses and the power design method, a relatively miniaturized optical lens design can be achieved while ensuring small imaging aberrations and high image quality. Furthermore, the condition that ENPD / TTL > 0.2 with respect to the entrance pupil diameter ENPD of the optical lens facilitates the achievement of large aperture characteristics, providing more incident light to the optical lens and improving the imaging effect of the optical lens.

Description

Technical Field

[0001] This utility model relates to the field of optical device technology, and in particular to an optical lens. Background Technology

[0002] With the continuous development of technology, the automotive industry has also ushered in the era of intelligence. Intelligent driving assistance systems, as a crucial component of automotive intelligence, play a vital role in improving driving safety, reducing accident rates, and enhancing user experience. In the current booming development of automotive driver assistance technologies, in-vehicle cameras hold a pivotal position. In-vehicle cameras come in various types, including interior, rear, front, side, and surround view cameras. Each type has unique functions and different application scenarios.

[0003] The forward-facing camera is a core component of Advanced Driver Assistance Systems (ADAS). It not only bears the heavy responsibility of distance measurement but also accurately identifies objects and clearly distinguishes road markings. Therefore, the required visual algorithms are extremely complex, posing a high technical barrier. However, most existing automotive optical lenses struggle to meet these requirements, making the development of a high-resolution, miniaturized optical lens with a large aperture a top priority. Utility Model Content

[0004] This invention provides an optical lens that achieves a lens design that balances large aperture and high resolution.

[0005] This utility model embodiment provides an optical lens, including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane;

[0006] The first lens, the sixth lens, and the eighth lens are all negative power lenses, while the second lens, the third lens, the fourth lens, the fifth lens, and the seventh lens are all positive power lenses.

[0007] The entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: ENPD / TTL > 0.2.

[0008] Optionally, between the focal length f1 of the first lens and the overall focal length F of the optical lens, the following relation is satisfied: -2<f1 / F<0; between the focal length f2 of the second lens and the overall focal length F of the optical lens, the following relation is satisfied: 0<f2 / F<2; between the focal length f3 of the third lens and the overall focal length F of the optical lens, the following relation is satisfied: 0<f3 / F<5; between the focal length f4 of the fourth lens and the overall focal length F of the optical lens, the following relation is satisfied: 0<f4 / F<2; between the focal length f5 of the fifth lens and the overall focal length F of the optical lens, the following relation is satisfied: 0<f5 / F<2; between the focal length f6 of the sixth lens and the overall focal length F of the optical lens, the following relation is satisfied: -2<f6 / F<0; between the focal length f7 of the seventh lens and the overall focal length F of the optical lens, the following relation is satisfied: 0<f7 / F<2; between the focal length f8 of the eighth lens and the overall focal length F of the optical lens, the following relation is satisfied: -2<f8 / F<0.

[0009] Optionally, between the focal length f1 of the first lens and the focal length f2 of the second lens, the following relation is satisfied: 0<|f1+f2| / |f1-f2|<1.

[0010] Optionally, the first lens and the second lens are cemented, or the first lens and the second lens are arranged independently;

[0011] The fifth lens and the sixth lens are cemented.

[0012] Optionally, between the focal length f5 of the fifth lens and the focal length f6 of the sixth lens, the following relation is satisfied: 0.5<|f5 / f6|<1.5.

[0013] Optionally, between the focal length f56 of the cemented lens formed by the fifth lens and the sixth lens and the overall focal length F of the optical lens, the following relation is satisfied: 2≤|f56 / F|≤4.

[0014] Optionally, the first lens includes a first object-side surface near the object plane and a first image-side surface near the image plane, wherein the first object-side surface and the first image-side surface are concave; the second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane, wherein the second object-side surface and the second image-side surface are convex; the third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane, wherein the third object-side surface is convex and the third image-side surface is concave; the fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane, wherein the fourth object-side surface is convex and the fourth image-side surface is convex. The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane, both of which are convex. The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane, both of which are concave. The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane, both of which are convex. The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane, both of which are concave.

[0015] Optionally, the central curvature radius R1 of the object side of the first lens and the central curvature radius R2 of the image side of the first lens satisfy the following condition: 0.4 < (R1 + R2) / R2 < 1.

[0016] Optionally, the central curvature radius R1 of the object side of the first lens and the central curvature radius R2 of the image side of the first lens satisfy the following condition: -0.6 < (R1 + R2) / (R1 - R2) < -0.2.

[0017] Optionally, the central radius of curvature R5 of the object side of the third lens, the central radius of curvature R6 of the image side of the third lens, and the central thickness d3 of the third lens satisfy the following: 0.5≤R5 / (R6+d3)≤1.2.

[0018] Optionally, the central radius of curvature R6 of the image side of the third lens and the total focal length F of the optical lens satisfy the following condition: R6 / F < 1.

[0019] Optionally, the central radius of curvature R13 of the side surface of the seventh lens satisfies the following relationship with the total focal length F of the optical lens: R13 / F > 6.

[0020] Optionally, the central curvature radius R13 of the object side of the seventh lens and the central curvature radius R14 of the image side of the seventh lens satisfy the following condition: 0.5 < (R13 + R14) / (R13 - R14) < 1.0.

[0021] Optionally, the total optical length TTL of the optical lens and the image height H corresponding to the maximum field of view of the optical lens satisfy the following relationship: 6 < TTL / H < 7.0.

[0022] Optionally, the total focal length F of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: TTL / F < 2.5.

[0023] Optionally, the optical back focal length (BFL) of the optical lens and the total optical length (TTL) of the optical lens satisfy the following condition: BFL / TTL > 0.2.

[0024] Optionally, the first lens, the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are all glass spherical lenses, and the fourth lens is a glass aspherical lens.

[0025] Optionally, the optical lens further includes an aperture stop located in the optical path between the third lens and the fourth lens.

[0026] The optical lens provided in this embodiment includes eight lenses with optical power. By reasonably setting the number of lenses, the total length of the optical lens can be ensured to be appropriate, achieving a relatively miniaturized design while maintaining small imaging aberrations and high image quality. Furthermore, the optical power of the eight lenses is arranged in a negative-positive-positive-positive-positive-negative-positive-negative pattern. This reasonable arrangement of the eight lenses' optical power allows for an increase in the aperture and improved imaging resolution. Moreover, the entrance pupil diameter (ENPD) and total optical length (TTL) of the optical lens satisfy ENPD / TTL > 0.2, which facilitates a large aperture characteristic, providing more incident light and improving the imaging effect.

[0027] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of an optical lens provided in Embodiment 1 of this utility model;

[0030] Figure 2 This is a schematic diagram of the light fan of an optical lens provided in Embodiment 1 of this utility model;

[0031] Figure 3 This is a schematic diagram of the axial aberration curve of an optical lens provided in Embodiment 1 of this utility model;

[0032] Figure 4 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 1 of this utility model;

[0033] Figure 5 This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model;

[0034] Figure 6 This is a schematic diagram of the light fan of an optical lens according to Embodiment 2 of this utility model;

[0035] Figure 7 This is a schematic diagram of the axial aberration curve of an optical lens provided in Embodiment 2 of this utility model;

[0036] Figure 8 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 2 of this utility model;

[0037] Figure 9 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model;

[0038] Figure 10 This is a schematic diagram of the light fan of an optical lens provided in Embodiment 3 of this utility model;

[0039] Figure 11 This is a schematic diagram of the axial aberration curve of an optical lens provided in Embodiment 3 of this utility model;

[0040] Figure 12 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 3 of this utility model;

[0041] Figure 13 This is a schematic diagram of the structure of an optical lens provided in Embodiment 4 of this utility model;

[0042] Figure 14 This is a schematic diagram of the light fan of an optical lens provided in Embodiment 4 of this utility model;

[0043] Figure 15 This is a schematic diagram of the axial aberration curve of an optical lens provided in Embodiment 4 of this utility model;

[0044] Figure 16 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 4 of this utility model. Detailed Implementation

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0046] Example 1

[0047] Figure 1 This is a schematic diagram of the structure of an optical lens provided in Embodiment 1 of this utility model, as shown below. Figure 1 As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 101, the sixth lens 106, and the eighth lens 108 are all negative power lenses, and the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, and the seventh lens 107 are all positive power lenses; the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the condition: ENPD / TTL > 0.2.

[0048] like Figure 1 As shown, the optical lens provided in this embodiment of the present invention includes eight lenses with optical power. The arrangement of eight lenses with optical power ensures that the number of lenses in the optical lens is reasonable. Too many lenses will result in a large lens size, and too few lenses will result in a large aberration due to a single lens bearing a large optical power. This ensures that the optical lens is miniaturized while ensuring small imaging aberrations and high imaging quality.

[0049] Furthermore, optical power is equal to the difference between the convergence of the beam at the image plane and the convergence of the beam at the object plane, characterizing the ability of an optical system to deflect light. The larger the absolute value of the optical power, the stronger the bending ability of light; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light is converging; when the optical power is negative, the refraction of light is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., a surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group). In this embodiment, the first lens 101 has a negative optical power. As the first lens in the optical lens to adjust the incident light, the negative optical power setting of the first lens 101 ensures that the light has a larger aperture before entering the aperture stop, increasing the aperture of the optical lens and enabling the lens to still form a clear image under dim or dark conditions. The second lens 102, third lens 103, fourth lens 104, and fifth lens 105 all have positive optical angles. Their positive optical power settings allow for timely correction of the significant aberrations produced by the first lens 101, particularly effectively correcting edge aberrations in the optical lens, thereby improving the imaging resolution of the optical system. Furthermore, the sixth lens 106 has a negative optical power, the seventh lens 107 has a positive optical power, and the eighth lens 108 has a negative optical power. The optical power of each subsequent lens in the optical path differs from that of the preceding lens, which is beneficial for aberration correction.

[0050] Furthermore, the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy ENPD / TTL > 0.2. Meeting the above range can achieve a small FNO, which is beneficial to realizing the large aperture characteristics of the optical lens, providing more incident light to the optical lens, and improving the imaging effect of the optical lens.

[0051] In summary, the optical lens provided by this embodiment of the invention, by reasonably setting the number of lenses, can ensure a suitable total length of the optical lens, achieving a relatively miniaturized design while maintaining small imaging aberrations and high image quality. Furthermore, the optical power of the eight lenses is arranged in a negative-positive-positive-positive-positive-negative-positive-negative pattern. This reasonable arrangement of the eight lenses' optical power increases the aperture of the optical lens and improves its imaging resolution. Moreover, the entrance pupil diameter (ENPD) and the total optical length (TTL) of the optical lens satisfy ENPD / TTL > 0.2, which facilitates a large aperture characteristic, providing more incident light and improving the imaging effect of the optical lens.

[0052] Based on the above embodiments, continue to refer to Figure 1As shown, the optical lens provided in the embodiment of the present utility model may further comprise a stop STO and a filter 109, wherein the stop STO is arranged in an optical path between a third lens 103 and a fourth lens 104, and the filter 109 is arranged in an optical path between an eighth lens 108 and an image plane.

[0053] Specifically, arranging the stop STO can adjust the propagation direction of light beams, which is beneficial to improving imaging quality. In the optical lens, arranging the stop STO in the optical system can limit the beam size and control the luminous flux of the lens, which is beneficial to reducing the aperture value and realizing a large aperture. The filter 109 can filter out stray light and improve the imaging effect.

[0054] Further, the optical lens provided in the embodiment of the present utility model may further comprise a protective glass and an imaging sensor, wherein the protective glass can be arranged on the image side surface of the filter, and the imaging sensor can be arranged on the image side surface of the protective glass. The optical system is protected by the protective glass, and images are collected by the imaging sensor, so that the normal imaging function of the optical system is realized.

[0055] Based on the above embodiment, between the focal length f1 of the first lens 101 and the overall focal length F of the optical lens, the relationship -2<f1 / F<0 is satisfied; between the focal length f2 of the second lens 102 and the overall focal length F of the optical lens, the relationship 0<f2 / F<2 is satisfied; between the focal length f3 of the third lens 103 and the overall focal length F of the optical lens, the relationship 0<f3 / F<5 is satisfied; between the focal length f4 of the fourth lens 104 and the overall focal length F of the optical lens, the relationship 0<f4 / F<2 is satisfied; between the focal length f5 of the fifth lens 105 and the overall focal length F of the optical lens, the relationship 0<f5 / F<2 is satisfied; between the focal length f6 of the sixth lens 106 and the overall focal length F of the optical lens, the relationship -2<f6 / F<0 is satisfied; between the focal length f7 of the seventh lens 107 and the overall focal length F of the optical lens, the relationship 0<f7 / F<2 is satisfied; and between the focal length f8 of the eighth lens 108 and the overall focal length F of the optical lens, the relationship -2<f8 / F<0 is satisfied.

[0056] Specifically, the relationship -2<f1 / F<0 satisfied between the focal length f1 of the first lens 101 and the overall focal length F of the optical lens means that the first lens 101 has appropriate negative optical power, which is beneficial to expanding the field angle of the optical lens.

[0057] The relationship 0<f2 / F<2 satisfied between the focal length f2 of the second lens 102 and the overall focal length F of the optical lens means that the second lens 102 has appropriate positive optical power, which is beneficial to the smooth transition of light, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0058] The focal length f3 of the third lens 103 is set to satisfy 0 < f3 / F < 5 with the total focal length F of the optical lens. This means that the third lens 103 has an appropriate positive power, which is conducive to smooth light transition, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0059] For lenses with excessive optical power, temperature changes can cause more significant focal length shifts. Therefore, by setting the focal length value f4 of the fourth lens 104 to satisfy 0 < f4 / F < 2 with the total focal length value F of the optical lens, the optical power of this lens can be controlled, and the focal length shift can be effectively controlled within a reasonable range. This ensures that the lens can still maintain good image quality under different temperature conditions.

[0060] Similarly, setting the focal length f5 of the fifth lens 105 to satisfy 0 < f5 / F < 2 with the total focal length F of the optical lens not only allows for a reasonable allocation of the optical power of the entire optical system, but also helps to achieve temperature characteristics, ensuring that the lens can still maintain good image quality under high and low temperature conditions.

[0061] Setting the focal length f6 of the sixth lens 106 to satisfy -2 < f6 / F < 0 with the total focal length F of the optical lens is beneficial for further diverging of light, realizing large target surface imaging of the lens, and improving the imaging quality of the optical lens.

[0062] The focal length f7 of the seventh lens 107 is set to satisfy 0 < f7 / F < 2 with the total focal length F of the optical lens. This means that the seventh lens 107 has appropriate positive power, which is beneficial for optical convergence, can effectively correct aberrations, and improve image quality.

[0063] Setting the focal length f8 of the eighth lens 108 to satisfy -2 < f8 / F < 0 with the total focal length F of the optical lens, by constraining the ratio of the optical power of the eighth lens 108 to the effective focal length of the optical imaging system within a reasonable range, can balance the remaining spherical aberration after balancing to balance the spherical aberration generated by the first seven lenses, thereby fine-tuning and controlling the spherical aberration of the system and improving the imaging quality.

[0064] Based on the above embodiments, the focal length value f1 of the first lens 101 and the focal length value f2 of the second lens 102 satisfy the following condition: 0 < |f1+f2| / |f1-f2| < 1. By reasonably controlling the focal length ratio of the first lens 101 and the second lens 102, the optical system can obtain a high imaging resolution, ensuring the imaging effect of the optical lens.

[0065] Based on the above embodiments, the first lens 101 and the second lens 102 are cemented together, or the first lens 101 and the second lens 102 are independently disposed;

[0066] The fifth lens 105 and the sixth lens 106 are cemented together.

[0067] Specifically, different lens bonding arrangements can be understood as the image-side surface of the preceding lens and the object-side surface of the following lens being bonded together in the optical path, possessing the same surface shape. In this embodiment of the present invention, the bonding arrangement of the first lens 101 and the second lens 102 can be understood as the image-side surface of the first lens 101 and the object-side surface of the second lens 102 being bonded together to form two bonded lenses; the bonding arrangement of the fifth lens 105 and the sixth lens 106 can be understood as the image-side surface of the fifth lens 105 and the object-side surface of the sixth lens 106 being bonded together to form two bonded lenses; such as Figure 1 As shown. Cemented lenses can be used to minimize or eliminate chromatic aberration. Using cemented lenses in optical lenses can improve image quality and reduce light energy reflection loss, thereby enhancing the sharpness of the image. Furthermore, the cementation eliminates the air gap between the two lenses, making the overall optical lens compact and meeting the requirements of system miniaturization. Moreover, the cementation reduces tolerance sensitivity issues such as tilting / eccentricity that occur during lens unit assembly. The two cemented lenses can be supported by spacers or bonded with adhesive; this embodiment does not limit the specific method of cementation.

[0068] Alternatively, the first lens 101 and the second lens 102 can be set independently, that is, the first lens 101 and the second lens 102 are not glued together. This can reduce the risk of reliability and avoid the glue cracking under long-term light exposure.

[0069] Based on the above embodiment, the focal length f5 of the fifth lens 105 and the focal length f6 of the sixth lens 106 satisfy the condition: 0.5 < |f5 / f6| < 1.5. Meeting this condition ensures that the focal lengths of the two lenses in the cemented lens are close, and the sixth lens 106 can effectively balance the aberrations generated by the fifth lens 105, achieving mutual cancellation and effectively improving the lens's resolving power.

[0070] Based on the above embodiments, the focal length f56 of the cemented lens composed of the fifth lens 105 and the sixth lens 106 satisfies the following relationship with the overall focal length F of the optical lens: 2 ≤ |f56 / F| ≤ 4. By appropriately setting the optical power of the cemented lens, the achromatic aberration capability of the fifth lens 105 and the sixth lens 106 can be effectively improved, allowing light passing through the cemented lens to enter the image plane more uniformly. This also helps more light to enter the cemented lens smoothly and improves illumination, thereby enhancing the imaging quality of the optical lens.

[0071] Based on the above embodiments, the first lens 101 includes a first object-side surface near the object plane and a first image-side surface near the image plane, both of which are concave; the second lens 102 includes a second object-side surface near the object plane and a second image-side surface near the image plane, both of which are convex; the third lens 103 includes a third object-side surface near the object plane and a third image-side surface near the image plane, both of which are convex; the fourth lens 104 includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane, both of which are convex. The fifth lens 105 includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane, both of which are convex. The sixth lens 106 includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane, both of which are concave. The seventh lens 107 includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane, both of which are convex. The eighth lens 108 includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane, both of which are concave.

[0072] Specifically, the object-side surface of a lens can be understood as the surface of the lens closest to the object plane, and the image-side surface of a lens can be understood as the surface of the lens closest to the image plane.

[0073] In this embodiment of the invention, the object-side surface of the first lens 101 is concave, and the image-side surface is also concave. This can be understood as the object-side surface of the first lens 101 being concave towards the object plane near the optical axis, and the image-side surface being concave towards the image plane near the optical axis. In other words, the first lens 101 is a double-concave lens. Designing the image-side surface as concave allows light to enter the system with a smaller deflection angle, which is beneficial for achieving a larger aperture and smaller aberrations.

[0074] The object-side surface of the second lens 102 can be convex, and the image-side surface can also be convex. This can be understood as the object-side surface of the second lens 102 bulging towards the object plane near the optical axis, and the image-side surface bulging towards the image plane near the optical axis. In other words, the second lens 102 is a biconvex lens. Furthermore, the concave image-side surface of the first lens 101 and the convex object-side surface of the second lens 102 facilitate the cemented bonding of the first lens 101 and the second lens 102.

[0075] The object side of the third lens 103 is convex, and the image side is concave. This can be understood as the object side of the third lens 103 convex towards the object surface near the optical axis, and the image side concave towards the image surface near the optical axis. In other words, the third lens 103 is a lens with a convex-concave structure.

[0076] The object side of the fourth lens 104 is convex, and the image side is also convex. This can be understood as the object side of the fourth lens 104 convex towards the object surface near the optical axis, and the image side convex towards the image surface near the optical axis. In other words, the third lens 103 is a lens with a biconvex structure.

[0077] The object-side surface of the fifth lens 105 is convex, and the image-side surface is also convex. This can be understood as the object-side surface of the fifth lens 105 convex towards the object surface near the optical axis, and the image-side surface convex towards the image surface near the optical axis. In other words, the fifth lens 105 is a lens with a biconvex structure.

[0078] The object-side surface of the sixth lens 106 is concave, and the image-side surface is also concave. This can be understood as the object-side surface of the sixth lens 106 being concave towards the object plane near the optical axis, and the image-side surface being concave towards the image plane near the optical axis. In other words, the sixth lens 106 can be a double-concave lens. Furthermore, the convex image-side surface of the fifth lens 105 and the concave object-side surface of the sixth lens 106 facilitate the cemented bonding of the fifth lens 105 and the sixth lens 106.

[0079] The object-side surface of the seventh lens 107 is convex, and the image-side surface is also convex. This can be understood as the object-side surface of the seventh lens 107 convex towards the object surface near the optical axis, and the image-side surface convex towards the image surface near the optical axis. In other words, the seventh lens 107 is a lens with a biconvex structure.

[0080] The object side of the eighth lens 108 is concave, and the image side is concave. This can be understood as the object side of the eighth lens 108 being concave towards the object plane near the optical axis, and the image side being concave towards the image plane near the optical axis. In other words, the eighth lens 108 is a lens with a double concave structure.

[0081] By properly setting the concave and convex surfaces of each lens, it is possible to ensure that each lens modulates the light emission angle and reduce the spacing between adjacent lenses, which is beneficial for achieving small-volume optical lens design.

[0082] Based on the above embodiments, the central radius of curvature R1 of the object side of the first lens 101 and the central radius of curvature R2 of the image side of the first lens 101 satisfy the following condition: 0.4 < (R1 + R2) / R2 < 1. By controlling the radii of curvature of the object side and the image side of the first lens 101, the imaging quality of the edge field of view can be reasonably controlled, and the sensitivity of the system can be effectively reduced.

[0083] Based on the above embodiments, the central radius of curvature R1 of the object side of the first lens 101 and the central radius of curvature R2 of the image side of the first lens 101 satisfy the following condition: -0.6 < (R1 + R2) / (R1 - R2) < -0.2. Controlling the first lens 101 to have an appropriate surface shape is beneficial to increasing the divergence of light, realizing large target surface imaging of the lens, and improving the imaging quality of the optical lens.

[0084] Based on the above embodiments, the central radius of curvature R5 of the object side of the third lens 103, the central radius of curvature R6 of the image side of the third lens 103, and the central thickness d3 of the third lens 103 satisfy the following condition: 0.5 ≤ R5 / (R6+d3) ≤ 1.2. Meeting this condition, the shape of the third lens 103 is close to a concentric circle, resulting in an optical path difference between the peripheral rays and the central rays, diverging the central rays and allowing them to enter the rear optical system. Furthermore, it reduces the front aperture of the lens, decreasing its size and facilitating miniaturization and cost reduction.

[0085] Based on the above embodiments, the central radius of curvature R6 of the image side of the third lens 103 and the total focal length F of the optical lens satisfy the condition: R6 / F < 1. Satisfying this condition allows the relative position of the pupil image of the ghost image reflected from the image side of the third lens 103 on the focal plane to be changed. By controlling the radius of curvature, the pupil image of the ghost image can be moved away from the focal plane, effectively reducing the relative energy value of the ghost image and achieving the requirement of weak ghosting.

[0086] Based on the above embodiments, the central radius of curvature R13 of the object side of the seventh lens 107 satisfies the condition R13 / F > 6 with the overall focal length F of the optical lens. Satisfying this condition allows the relative position of the pupil image of the ghost image reflected from the object side of the seventh lens 107 on the focal plane to be changed. By controlling the radius of curvature, the pupil image of the ghost image can be moved away from the focal plane, effectively reducing the relative energy value of the ghost image and achieving the requirement of weak ghosting.

[0087] Based on the above embodiments, the central radius of curvature R13 of the object side of the seventh lens 107 and the central radius of curvature R14 of the image side of the seventh lens 107 satisfy the following condition: 0.5 < (R13 + R14) / (R13 - R14) < 1.0. Controlling the seventh lens 107 to have an appropriate surface shape is beneficial for light convergence, allowing the light path to transition smoothly to the rear, reducing the height of the incident light rays, mitigating the upward trend of the light rays, and improving the illumination of the edge field of view.

[0088] Based on the above embodiments, the total optical length (TTL) of the optical lens and the image height (H) corresponding to the maximum field of view of the optical lens satisfy the following relationship: 6 < TTL / H < 7.0. This allows for a large image area while better compressing the overall length of the lens, enabling miniaturization of the lens design and facilitating its integration with other imaging devices.

[0089] Based on the above embodiments, the overall focal length F of the optical lens and the total optical length TTL of the optical lens satisfy the condition: TTL / F < 2.5. By controlling the total length of the lens in this way, a miniaturized optical lens can be obtained.

[0090] Based on the above embodiments, the optical back focal length (BFL) of the optical lens and the total optical length (TTL) of the optical lens satisfy the condition: BFL / TTL > 0.2. This ensures sufficient back focal length while achieving miniaturization, which is beneficial for module assembly.

[0091] Based on the above embodiments, the first lens 101, the second lens 102, the third lens 103, the fifth lens 105, the sixth lens 106, the seventh lens 107 and the eighth lens 108 are all glass spherical lenses, and the fourth lens 104 is a glass aspherical lens.

[0092] Specifically, a characteristic of spherical lenses is that they have a constant curvature from the center to the periphery, ensuring a simple lens setup. Furthermore, because glass lenses have a low coefficient of thermal expansion and good stability, the first lens 101, second lens 102, third lens 103, fifth lens 105, sixth lens 106, seventh lens 107, and eighth lens 108 are all glass spherical lenses. The thermal properties of glass spherical lenses are more stable, ensuring good resolution over a wide temperature range when handling higher optical powers.

[0093] Aspherical lenses are characterized by a continuous change in curvature from the center to the periphery, unlike spherical lenses which have a constant curvature from the center to the periphery. Aspherical lenses have better curvature radius characteristics, which improves distortion aberrations and astigmatism. Using an aspherical lens as the fourth lens 104 can improve the aberrations of optical lenses.

[0094] Furthermore, there is a wider range of glass materials to choose from, and the refractive index and Abbe number can be selected more freely, which can control the advanced aberrations and chromatic aberrations of the lens to a certain extent and meet the needs of use under complex conditions.

[0095] Therefore, the optical lens provided in this embodiment of the present invention can adopt a combination of glass spherical lenses and glass aspherical lenses, which can ensure the optical performance of the optical lens and guarantee normal use in high and low temperature environments.

[0096] As a feasible implementation method, the parameters of each lens in the optical lens will be explained next.

[0097] Table 1. Optical design values ​​for the optical lens in Example 1

[0098]

[0099] Table 2 Design values ​​of optical physical parameters of optical lenses

[0100]

[0101] The surface numbers in Table 2 are assigned according to the surface sequence of each lens, where "1" represents the front surface of the first lens, "2" represents the rear surface of the first lens, and so on; the radius of curvature represents the curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane, where "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the central axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface, with a blank space indicating that the current position is air.

[0102] In this embodiment of the invention, the fourth lens is an aspherical lens, with both its object-side surface 7 and image-side surface 8 being aspherical. Its aspherical surface shape equation Z satisfies:

[0103]

[0104] Where z is the axial sagitta in the Z direction of the aspherical surface; r is the height of the aspherical surface; c is the curvature of the fitted sphere, which is numerically the reciprocal of the radius of curvature; k is the fitted conic coefficient; and A, B, C, D, and E are higher-order aspherical coefficients.

[0105] Table 3 Aspherical coefficients of optical lenses

[0106]

[0107] Where -1.8E-05 represents -1.8 * 10 -5 All other parameters can be represented in this way.

[0108] Figure 2 This is a schematic diagram of the ray fan of an optical lens according to Embodiment 1 of this utility model. The horizontal axis of the ray fan diagram represents the normalized pupil aperture, and the vertical axis represents the distance of the corresponding ray from the principal ray on the image plane. It should be noted that the principal ray is the ray that passes through the center of the entrance pupil. Ideally, each curve completely coincides with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. Figure 2 As shown, the curves of the light fan plots for different wavelengths in all fields of view are close to the horizontal axis, and the curves of each color have a high degree of concentration. This indicates that the aberrations of each field of view of the optical lens are well corrected, which can ensure that the vehicle lens can achieve clear imaging in a wide spectral range.

[0109] Figure 3This is a schematic diagram of the axial aberration curve of an optical lens according to Embodiment 1 of this utility model. The vertical direction represents the normalized aperture, 0 indicates that it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). Different colored curves in the figure represent different wavelengths of the system imaging, determined by... Figure 3 It can be seen that the axial aberrations of different wavelengths (436nm, 486nm, 546nm, 588nm and 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the aberrations of the optical lens at each wavelength are well controlled and can meet the requirements of wide spectrum applications.

[0110] Figure 4 This is a schematic diagram of field curvature distortion of an optical lens according to Embodiment 1 of this utility model, as shown below. Figure 4 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 4 As can be seen, the lens provided in this embodiment effectively controls the field curvature from light wavelengths of 436nm to 656nm, meaning that during imaging, the difference in image quality between the center and the periphery is small. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 4 As can be seen, the imaging distortion of the lens provided in this embodiment is less than 5%, indicating that the lens distortion has been well corrected and the optical lens has a good imaging effect.

[0111] In summary, the optical lens provided by this utility model adopts an 8-element structure. By adjusting the lens shape, lens material combination, and different optical power combinations, it achieves the technical effects of high pixel count, miniaturization, high definition, large aperture, weak ghosting, and a total length within 32mm. It is an 8-megapixel forward-looking telephoto narrow-angle lens for autonomous driving that can effectively capture the most realistic photos.

[0112] Example 2

[0113] Figure 5 This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model, as shown below. Figure 5As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 101, the sixth lens 106, and the eighth lens 108 are all negative power lenses, and the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, and the seventh lens 107 are all positive power lenses; the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the condition: ENPD / TTL > 0.2.

[0114] Other parameters are the same as in Example 1, and will not be repeated here.

[0115] As another feasible implementation method, the specific parameters of the optical lens are explained below.

[0116] Table 4. Optical design values ​​for the optical lens in Example 2

[0117]

[0118] Table 5 Design values ​​of optical physical parameters of optical lenses

[0119]

[0120] The surface numbers in Table 5 are assigned according to the surface sequence of each lens, where "1" represents the front surface of the first lens, "2" represents the rear surface of the first lens, and so on; the radius of curvature represents the curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane, where "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the central axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface, with a blank space indicating that the current position is air.

[0121] In this embodiment of the invention, the fourth lens is an aspherical lens, with both its object-side surface 7 and image-side surface 8 being aspherical. Its aspherical surface shape equation Z satisfies:

[0122]

[0123] Where z is the axial sagitta in the Z direction of the aspherical surface; r is the height of the aspherical surface; c is the curvature of the fitted sphere, which is numerically the reciprocal of the radius of curvature; k is the fitted conic coefficient; and A, B, C, D, and E are higher-order aspherical coefficients.

[0124] Table 6 Aspherical coefficients of optical lenses

[0125]

[0126] Wherein, -2.5E-05 represents -2.5 * 10 -5 All other parameters can be represented in this way.

[0127] Figure 6 This is a schematic diagram of the ray fan of an optical lens according to Embodiment 2 of this utility model. The horizontal axis of the ray fan diagram represents the normalized pupil aperture, and the vertical axis represents the distance of the corresponding ray from the principal ray on the image plane. It should be noted that the principal ray is the ray that passes through the center of the entrance pupil. Ideally, each curve completely coincides with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. Figure 6 As shown, the curves of the light fan plots for different wavelengths in all fields of view are close to the horizontal axis, and the curves of each color have a high degree of concentration. This indicates that the aberrations of each field of view of the optical lens are well corrected, which can ensure that the vehicle lens can achieve clear imaging in a wide spectral range.

[0128] Figure 7 This is a schematic diagram of the axial aberration curve of an optical lens according to Embodiment 2 of this utility model. The vertical direction represents the normalized aperture, 0 indicates that it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). Different colored curves in the figure represent different wavelengths of the system imaging, determined by... Figure 7 It can be seen that the axial aberrations of different wavelengths (436nm, 486nm, 546nm, 588nm and 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the aberrations of the optical lens at each wavelength are well controlled and can meet the requirements of wide spectrum applications.

[0129] Figure 8 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 2 of this utility model, as shown below. Figure 8 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 8 As can be seen, the lens provided in this embodiment effectively controls the field curvature from light wavelengths of 436nm to 656nm, meaning that during imaging, the difference in image quality between the center and the periphery is small. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 8As can be seen, the imaging distortion of the lens provided in this embodiment is less than 5%, indicating that the lens distortion has been well corrected and the optical lens has a good imaging effect.

[0130] In summary, the optical lens provided by this utility model adopts an 8-element structure. By adjusting the lens shape, lens material combination, and different optical power combinations, it achieves the technical effects of high pixel count, miniaturization, high definition, large aperture, weak ghosting, and a total length within 32mm. It is an 8-megapixel forward-looking telephoto narrow-angle lens for autonomous driving that can effectively capture the most realistic photos.

[0131] Example 3

[0132] Figure 9 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model, as shown below. Figure 9 As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 101, the sixth lens 106, and the eighth lens 108 are all negative power lenses, and the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, and the seventh lens 107 are all positive power lenses; the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the condition: ENPD / TTL > 0.2.

[0133] Other parameters are the same as in Example 1, and will not be repeated here.

[0134] As another feasible implementation method, the specific parameters of the optical lens are explained below.

[0135] Table 7. Optical design values ​​for the optical lens in Example 3

[0136]

[0137] Table 8 Design values ​​of optical physical parameters of optical lenses

[0138]

[0139] The surface numbers in Table 8 are assigned according to the surface sequence of each lens, where "1" represents the front surface of the first lens, "2" represents the rear surface of the first lens, and so on; the radius of curvature represents the curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane, where "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the central axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface, with a blank space indicating that the current position is air.

[0140] In this embodiment of the invention, the fourth lens is an aspherical lens, with both its object-side surface 7 and image-side surface 8 being aspherical. Its aspherical surface shape equation Z satisfies:

[0141]

[0142] Where z is the axial sagitta in the Z direction of the aspherical surface; r is the height of the aspherical surface; c is the curvature of the fitted sphere, which is numerically the reciprocal of the radius of curvature; k is the fitted conic coefficient; and A, B, C, D, and E are higher-order aspherical coefficients.

[0143] Table 9 Aspherical coefficients of optical lenses

[0144]

[0145] Where -1.8E-05 represents -1.8 * 10 -5 All other parameters can be represented in this way.

[0146] Figure 10 This is a schematic diagram of the ray fan of an optical lens according to Embodiment 3 of this utility model. The horizontal axis of the ray fan diagram represents the normalized pupil aperture, and the vertical axis represents the distance of the corresponding ray from the principal ray on the image plane. It should be noted that the principal ray is the ray that passes through the center of the entrance pupil; ideally, each curve completely coincides with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane; as shown... Figure 10 As shown, the curves of the light fan plots for different wavelengths in all fields of view are close to the horizontal axis, and the curves of each color have a high degree of concentration. This indicates that the aberrations of each field of view of the optical lens are well corrected, which can ensure that the vehicle lens can achieve clear imaging in a wide spectral range.

[0147] Figure 11This is a schematic diagram of the axial aberration curve of an optical lens according to Embodiment 3 of this utility model. The vertical direction represents the normalized aperture, 0 indicates that it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). Different colored curves in the figure represent different wavelengths of the system imaging, determined by... Figure 11 It can be seen that the axial aberrations of different wavelengths (436nm, 486nm, 546nm, 588nm and 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the aberrations of the optical lens at each wavelength are well controlled and can meet the requirements of wide spectrum applications.

[0148] Figure 12 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 3 of this utility model, as shown below. Figure 12 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 12 As can be seen, the lens provided in this embodiment effectively controls the field curvature from light wavelengths of 436nm to 656nm, meaning that during imaging, the difference in image quality between the center and the periphery is small. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 12 As can be seen, the imaging distortion of the lens provided in this embodiment is less than 5%, indicating that the lens distortion has been well corrected and the optical lens has a good imaging effect.

[0149] In summary, the optical lens provided by this utility model adopts an 8-element structure. By adjusting the lens shape, lens material combination, and different optical power combinations, it achieves the technical effects of high pixel count, miniaturization, high definition, large aperture, weak ghosting, and a total length within 32mm. It is an 8-megapixel forward-looking telephoto narrow-angle lens for autonomous driving that can effectively capture the most realistic photos.

[0150] Example 4

[0151] Figure 13 This is a schematic diagram of the structure of an optical lens provided in Embodiment 4 of this utility model, as shown below. Figure 13As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 101, the sixth lens 106, and the eighth lens 108 are all negative power lenses, and the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, and the seventh lens 107 are all positive power lenses; the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the condition: ENPD / TTL > 0.2.

[0152] Other parameters are the same as in Example 1, and will not be repeated here.

[0153] As another feasible implementation method, the specific parameters of the optical lens are explained below.

[0154] Table 10. Optical design values ​​for the optical lens in Example 4

[0155]

[0156] Table 11 Design values ​​of optical physical parameters of optical lenses

[0157]

[0158] The surface numbers in Table 11 are assigned according to the surface sequence of each lens, where "1" represents the front surface of the first lens, "2" represents the rear surface of the first lens, and so on; the radius of curvature represents the curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane, where "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the central axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface, with a blank space indicating that the current position is air.

[0159] In this embodiment of the invention, the fourth lens is an aspherical lens, with both its object-side surface 7 and image-side surface 8 being aspherical. Its aspherical surface shape equation Z satisfies:

[0160]

[0161] Where z is the axial sagitta in the Z direction of the aspherical surface; r is the height of the aspherical surface; c is the curvature of the fitted sphere, which is numerically the reciprocal of the radius of curvature; k is the fitted conic coefficient; and A, B, C, D, and E are higher-order aspherical coefficients.

[0162] Table 12 Aspherical coefficients of optical lenses

[0163]

[0164] Where -1.8E-05 represents -1.8 * 10 -5 All other parameters can be represented in this way.

[0165] Figure 14 This is a schematic diagram of the ray fan of an optical lens according to Embodiment 4 of this utility model. The horizontal axis of the ray fan diagram represents the normalized pupil aperture, and the vertical axis represents the distance of the corresponding ray from the principal ray on the image plane. It should be noted that the principal ray is the ray that passes through the center of the entrance pupil. Ideally, each curve completely coincides with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. Figure 14 As shown, the curves of the light fan plots for different wavelengths in all fields of view are close to the horizontal axis, and the curves of each color have a high degree of concentration. This indicates that the aberrations of each field of view of the optical lens are well corrected, which can ensure that the vehicle lens can achieve clear imaging in a wide spectral range.

[0166] Figure 15 This is a schematic diagram of the axial aberration curve of an optical lens according to Embodiment 4 of this utility model. The vertical direction represents the normalized aperture, 0 indicates that it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). Different colored curves in the figure represent different wavelengths of the system imaging, determined by... Figure 15 It can be seen that the axial aberrations of different wavelengths (436nm, 486nm, 546nm, 588nm and 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the aberrations of the optical lens at each wavelength are well controlled and can meet the requirements of wide spectrum applications.

[0167] Figure 16 This is a schematic diagram of field curvature distortion of an optical lens provided in Embodiment 4 of this utility model, as shown below. Figure 16 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 16 As can be seen, the lens provided in this embodiment effectively controls the field curvature from light wavelengths of 436nm to 656nm, meaning that during imaging, the difference in image quality between the center and the periphery is small. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 16As can be seen, the imaging distortion of the lens provided in this embodiment is less than 5%, indicating that the lens distortion has been well corrected and the optical lens has a good imaging effect.

[0168] In summary, the optical lens provided by this utility model adopts an 8-element structure. By adjusting the lens shape, lens material combination, and different optical power combinations, it achieves the technical effects of high pixel count, miniaturization, high definition, large aperture, weak ghosting, and a total length within 32mm. It is an 8-megapixel forward-looking telephoto narrow-angle lens for autonomous driving that can effectively capture the most realistic photos.

[0169] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An optical lens, characterized in that, It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane; The first lens, the sixth lens, and the eighth lens are all negative power lenses, while the second lens, the third lens, the fourth lens, the fifth lens, and the seventh lens are all positive power lenses. The entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: ENPD / TTL > 0.

2.

2. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens satisfies the following relationship with the total focal length F of the optical lens: -2 <f1 / F<0; The focal length value f2 of the second lens and the total focal length value F of the optical lens satisfy the following condition: 0 < f2 / F < 2; The focal length value f3 of the third lens and the total focal length value F of the optical lens satisfy the following condition: 0 < f3 / F < 5; The focal length value f4 of the fourth lens and the total focal length value F of the optical lens satisfy the following condition: 0 < f4 / F < 2; The focal length value f5 of the fifth lens and the total focal length value F of the optical lens satisfy the following condition: 0 < f5 / F < 2. The focal length value f6 of the sixth lens and the total focal length value F of the optical lens satisfy the following condition: -2 < f6 / F < 0; The focal length value f7 of the seventh lens and the total focal length value F of the optical lens satisfy the following condition: 0 < f7 / F < 2. The focal length f8 of the eighth lens satisfies the following relationship with the total focal length F of the optical lens: -2 < f8 / F < 0.

3. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens and the focal length f2 of the second lens satisfy the following condition: 0 < |f1+f2| / |f1-f2| < 1.

4. The optical lens according to claim 1, characterized in that, The first lens and the second lens are cemented together, or the first lens and the second lens are independently disposed; The fifth lens and the sixth lens are cemented together.

5. The optical lens according to claim 4, characterized in that, The focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy the following condition: 0.5 < |f5 / f6| < 1.

5.

6. The optical lens according to claim 4, characterized in that, The focal length f56 of the cemented lens formed by the fifth and sixth lenses satisfies the following relationship with the total focal length F of the optical lens: 2≤|f56 / F|≤4.

7. The optical lens according to claim 1, characterized in that, The first lens includes a first object-side surface near the object plane and a first image-side surface near the image plane, wherein the first object-side surface is concave and the first image-side surface is concave. The second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane, wherein the second object-side surface is convex and the second image-side surface is convex. The third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave. The fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex, and the fourth image-side surface is convex. The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane. The fifth object-side surface is convex, and the fifth image-side surface is convex. The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane. The sixth object-side surface is concave, and the sixth image-side surface is concave. The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane. The seventh object-side surface is convex, and the seventh image-side surface is convex. The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane. The eighth object-side surface is concave, and the eighth image-side surface is concave.

8. The optical lens according to claim 7, characterized in that, The central radius of curvature R1 of the object side of the first lens and the central radius of curvature R2 of the image side of the first lens satisfy the following condition: 0.4 < (R1 + R2) / R2 < 1.

9. The optical lens according to claim 7, characterized in that, The central radius of curvature R1 of the object side of the first lens and the central radius of curvature R2 of the image side of the first lens satisfy the following condition: -0.6 < (R1 + R2) / (R1 - R2) < -0.

2.

10. The optical lens according to claim 7, characterized in that, The central radius of curvature R5 of the object side of the third lens, the central radius of curvature R6 of the image side of the third lens, and the central thickness d3 of the third lens satisfy the following condition: 0.5≤R5 / (R6+d3)≤1.

2.

11. The optical lens according to claim 7, characterized in that, The central curvature radius R6 of the image side of the third lens satisfies the following relationship with the total focal length F of the optical lens: R6 / F < 1.

12. The optical lens according to claim 7, characterized in that, The central radius of curvature R13 of the side surface of the seventh lens satisfies the following relationship with the total focal length F of the optical lens: R13 / F > 6.

13. The optical lens according to claim 7, characterized in that, The central curvature radius R13 of the object side of the seventh lens and the central curvature radius R14 of the image side of the seventh lens satisfy the following condition: 0.5 < (R13 + R14) / (R13 - R14) < 1.

0.

14. The optical lens according to claim 1, characterized in that, The total optical length TTL of the optical lens and the image height H corresponding to the maximum field of view of the optical lens satisfy the following relationship: 6 < TTL / H < 7.

0.

15. The optical lens according to claim 1, characterized in that, The total focal length F of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: TTL / F < 2.

5.

16. The optical lens according to claim 1, characterized in that, The optical back focal length (BFL) of the optical lens and the total optical length (TTL) of the optical lens satisfy the following condition: BFL / TTL > 0.

2.

17. The optical lens according to claim 1, characterized in that, The first lens, the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are all glass spherical lenses, and the fourth lens is a glass aspherical lens.

18. The optical lens according to claim 1, characterized in that, The optical lens also includes an aperture stop, which is located in the optical path between the third lens and the fourth lens.

Images