Optical lens

Abstract

The application provides an optical lens, which comprises eight lenses in sequence along an optical axis from an object side to an imaging surface, and the eight lenses comprise: a first lens with negative optical power, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; a second lens with negative optical power, wherein the image side surface of the second lens is a concave surface; a third lens with negative optical power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens with positive optical power, wherein the image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; a sixth lens with negative optical power, wherein the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; a seventh lens with positive optical power, wherein the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface; and an eighth lens with negative optical power. The optical lens provided by the application has one or more advantages of super wide angle, high pixel, large aperture, small distortion, high imaging quality and the like through specific surface shape matching and reasonable optical power distribution.

Description

Technical Field

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

[0002] With the rapid development of fields such as drones, security, automobiles, meteorology, medical, VR, and AR, increasingly higher demands are being placed on the field of view of the lenses they are equipped with. Wide-angle lenses, by introducing barrel distortion, compress light at the edges of the field of view as much as possible, thus achieving an ultra-wide-angle lens with a field of view exceeding 220°. Currently, ultra-wide-angle lenses still have many problems. For example, common ultra-wide-angle lenses have relatively small apertures, resulting in insufficient light intake and unclear images. Additionally, aberration correction is difficult, and there are issues such as excessively large lens heads. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0004] This invention provides an optical lens comprising eight lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0005] The first lens with negative optical power has a convex object side and a concave image side.

[0006] A second lens with negative optical power has a concave image-side surface;

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

[0008] The fourth lens has positive optical power and its image-side surface is convex.

[0009] The fifth lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0010] The sixth lens has negative optical power, with both its object-side and image-side surfaces being concave.

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

[0012] The eighth lens with negative optical power has an object-side surface that is convex near the optical axis and an image-side surface that is concave.

[0013] Wherein, the combined focal length f123 of the first lens, the second lens, and the third lens satisfies the condition -1.6 with the effective focal length f of the optical lens. <f123 / f<-1.2。

[0014] More preferably, the combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -1.1 < f123 / f45678 < -0.9.

[0015] More preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -190 < f3 / f < -90; the object-side curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: 2.7 < R5 / f < 2.9.

[0016] More preferably, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 2.6 < f4 / f < 2.8; the image-side curvature radius R8 of the fourth lens and the effective focal length f of the optical lens satisfy: -1.7 < R8 / f < -1.4.

[0017] More preferably, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.9 < f5 / f < 2; the object-side curvature radius R9 of the fifth lens and the image-side curvature radius R10 of the fifth lens satisfy: 0.29 < (R9 + R10) / (R9 - R10) < 0.45.

[0018] More preferably, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2.9 < f6 / f < -2; the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: -0.5 < (R11 + R12) / (R11 - R12) < -0.3.

[0019] More preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.5 < f7 / f < 2.3; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: -1.5 < R14 / f < -0.9.

[0020] More preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.6 < IH / f < 3.8.

[0021] More preferably, the effective focal length f of the optical lens, the aperture value Fno of the optical lens and the overall optical length TTL of the optical lens satisfy: 0.19 < f × Fno / TTL < 0.2.

[0022] Further preferably, the clear aperture semi-diameter CSD11 of the object side surface of the first lens and the sagittal height SAG11 of the clear aperture semi-diameter of the object side surface of the first lens satisfy: 2.5 < CSD11 / SAG11 < 3.2; the clear aperture semi-diameter CSD12 of the image side surface of the first lens and the sagittal height SAG12 of the clear aperture semi-diameter of the image side surface of the first lens satisfy: 1.35 < CSD12 / SAG12 < 1.45.

[0023] Compared with the prior art, the optical lens provided by the present invention adopts eight lenses with specific optical powers. Through specific surface shape combinations and reasonable optical power distributions, it can improve the imaging quality of the optical lens, reduce aberrations, enhance the imaging quality of the optical lens, and endow the lens with one or more advantages such as ultra-wide angle, high pixel, large aperture, small distortion, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is an F-Theta distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0031] Figure 7 is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 8 is an F-Theta distortion curve diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 9 is an axial aberration curve diagram of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 10 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 11 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 12 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 13 This is the F-Theta distortion curve of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 14 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0039] Figure 15 This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0040] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0041] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0042] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0043] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0044] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0045] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0046] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so specified herein.

[0047] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0048] The optical lens provided in this embodiment of the invention comprises eight lenses, which are arranged sequentially along the optical axis from the object side to the imaging plane as follows: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens.

[0049] In some embodiments, the first lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The second lens may have negative optical power, with either a concave or convex object-side surface and a concave image-side surface. The third lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The fourth lens may have positive optical power, with either a concave or convex object-side surface and a convex image-side surface. The fifth lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The sixth lens may have negative optical power, with both a concave object-side surface and a concave image-side surface. The seventh lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The eighth lens may have negative optical power, with a convex object-side surface near the optical axis and a concave image-side surface.

[0050] In some embodiments, the optical lens may also include an aperture stop, which may be located between the fourth and fifth lenses. It is understood that the aperture stop is used to limit the amount of light entering the lens to change the brightness of the image. When the aperture stop is located between the fourth and fifth lenses, it facilitates the correction of aperture aberrations.

[0051] In some embodiments, the optical lens may further include a filter disposed between the eighth lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0052] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the effective focal length f of the optical lens satisfy: -1.6 < f123 / f < -1.2. Satisfying the above conditional formula, the front lens group composed of the first lens to the third lens is designed to have a negative optical power, enabling the optical lens to receive light rays in a large-angle field of view and facilitating the transmission of the large-angle light beam through the aperture, so as to meet the ultra-wide-angle requirement of the optical lens. At the same time, it also helps to improve the brightness of the edge field of view on the imaging surface, thereby enhancing the imaging clarity at the edge field of view.

[0053] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens satisfy: -1.1 < f123 / f45678 < -0.9. Satisfying the above conditional formula is conducive to reasonably controlling the focal length ratio of the lens groups before and after the aperture, achieving the effects of a large aperture and a large target surface for the optical lens. At the same time, the light rays can fill the entire aperture, which is beneficial to the aberration balance before and after the aperture of the optical lens.

[0054] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -190 < f3 / f < -90; satisfying the above conditional formula enables the third lens to provide negative refractive power for the optical lens, which is conducive to correcting the chromatic aberration of the optical lens and correcting the aberration of the optical lens, so as to improve the imaging resolution of the optical lens. At the same time, it is also beneficial to reduce the eccentricity sensitivity of the optical lens; at the same time, the third lens is also conducive to adjusting the light ray trend from the first lens and the second lens, making the edge light rays continue to diverge after passing through the third lens and correcting the edge field of view aberration.

[0055] In some embodiments, the curvature radius R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: 2.7 < R5 / f < 2.9. Satisfying the above conditional formula, such a setting makes the shape of the object side surface of the third lens convex, enabling the light rays passing through the second lens to converge into the third lens, which can reduce the size of the subsequent lenses, contribute to the miniaturization of the optical lens, and the third lens can effectively reduce the generation of spherical aberration and astigmatism to improve the imaging quality of the optical lens.

[0056] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 2.6 < f4 / f < 2.8. By satisfying the above conditional formula, by setting the fourth lens to have a large positive refractive power, the light rays from the first three lenses can be converged, and the aberration problems caused by the first three negative focal length lenses can be corrected, and the aberration of the edge field of view can be effectively improved, thereby enhancing the overall imaging quality of the optical lens.

[0057] In some embodiments, the image-side curvature radius R8 of the fourth lens and the effective focal length f of the optical lens satisfy: -1.7 < R8 / f < -1.4. By satisfying the above conditional formula, the surface shape of the image side of the fourth lens is controlled, the spherical aberration of the optical lens is effectively corrected, and at the same time the influence of astigmatism on the imaging of the optical lens is reduced. In addition, the trend of the light rays can be adjusted, enabling the optical lens to have a large viewing angle and be ultrathin.

[0058] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.9 < f5 / f < 2. By satisfying the above conditional formula, in cooperation with the fourth lens, the trend of the light rays is further restricted, and it is beneficial to correct the aberration generated by the refraction of the light rays by the previous lenses, ensuring the imaging quality.

[0059] In some embodiments, the object-side curvature radius R9 of the fifth lens and the image-side curvature radius R10 of the fifth lens satisfy: 0.29 < (R9 + R10) / (R9 - R10) < 0.45. By satisfying the above conditional formula, the fifth lens is designed as a biconvex surface type, which can reasonably increase the incident angle to meet the image height requirements of the optical lens, while reducing the sensitivity of the optical lens and improving the assembly stability.

[0060] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2.9 < f6 / f < -2. By satisfying the above conditional formula, the focal length value of the sixth lens is reasonably controlled, so that the light rays in the large viewing field are slowly lifted, and the tendency of the parallel light of the light beam changes to a divergent trend, which is beneficial to controlling the back focal length of the lens and is beneficial to achieving a large target surface and reducing the incident angle of the chief ray.

[0061] In some embodiments, the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: -0.5 < (R11 + R12) / (R11 - R12) < -0.3. By satisfying the above conditional formula, the sixth lens is designed as a biconcave surface type, ensuring that the sixth lens can better diverge the light rays, thereby reducing the risk of ghosting and enhancing the resolution ability of the system.

[0062] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.5 < f7 / f < 2.3. Meeting the above conditional formula, the positive refractive power intensity provided by the seventh lens for the optical lens can better constrain the rear-end light, thereby effectively correcting chromatic aberration. At the same time, as the lens at the rear-end position in the optical lens, the seventh lens can better correct the aberration generated by the decentration difference of each lens on the object side, that is, it can reduce the decentration sensitivity of the optical lens, suppress the astigmatism generated by the decentration of each lens on the object side, thereby realizing the correction of the aberration of the optical lens and improving the imaging resolution.

[0063] In some embodiments, the radius of curvature R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: -1.5 < R14 / f < -0.9. Meeting the above conditional formula, controlling the surface shape of the image side surface of the seventh lens can effectively correct the spherical aberration of the optical lens, while reducing the influence of astigmatism on the imaging of the optical lens. In addition, the trend of light can be adjusted to make the optical lens have a large field angle and be ultra-thin.

[0064] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.6 < IH / f < 3.8. Meeting the above conditional formula, controlling the ratio of the effective focal length to the image height of the optical lens, shortening the effective focal length can expand the field angle, enabling the optical lens to capture a wider object-side space, while making the optical lens match a large image-plane chip and improving the imaging quality of the optical lens.

[0065] In some embodiments, the effective focal length f of the optical lens, the aperture value Fno of the optical lens, and the total optical length TTL of the optical lens satisfy: 0.19 < f×Fno / TTL < 0.2. Meeting the above conditional formula, the optical lens satisfies the characteristics of short focal length with large aperture, allowing the optical lens to have sufficient light input, enabling the optical lens to have a large wide-angle field of view to capture more scene information, and using flexible depth-of-field control to enhance the sense of hierarchy of the picture, which is beneficial to making the captured image clearer. At the same time, the limitation of the total optical length makes the optical lens also meet the requirement of miniaturization.

[0066] In some embodiments, the clear aperture semi-diameter CSD11 of the object side surface of the first lens and the sagittal height SAG11 of the clear aperture of the object side surface of the first lens satisfy: 2.5 < CSD11 / SAG11 < 3.2; the clear aperture semi-diameter CSD12 of the image side surface of the first lens and the sagittal height SAG12 of the clear aperture of the image side surface of the first lens satisfy: 1.35 < CSD12 / SAG12 < 1.45. Meeting the above conditional formula is beneficial for large-angle light to enter the optical lens, improving the image height and imaging quality of the optical lens; at the same time, it avoids the surface shape of the object side and image side surfaces of the first lens from being too curved, reducing the processing difficulty of the first lens and the risk of generating ghost images, and avoiding the problem of uneven coating caused by the first lens being too curved.

[0067] In some embodiments, the distance CT23 between the second lens and the third lens on the optical axis, the distance CR34 between the third lens and the fourth lens on the optical axis, and the total optical length TTL of the optical lens satisfy: 0.075 ≤ (CT23 + CT34) / TTL ≤ 0.09. By satisfying the above conditional formula, through reasonable configuration of the air gaps between the second lens and the third lens, the third lens and the fourth lens on the optical axis and the total optical length of the optical lens, it is beneficial to shorten the total optical length of the optical lens, achieve miniaturized design, and at the same time is beneficial to the reasonable transition of light between the second lens, the third lens and the fourth lens, thereby being beneficial to improving the relative illumination of the optical lens.

[0068] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.6 < f2 / f < -3.1. By satisfying the above conditional formula, the second lens has a negative focal length, ensuring that the light beam entering the second lens diverges, slowly raising the light of the large field of view, being beneficial to achieving a large aperture and a large target surface, and at the same time being beneficial to the gentle trend of light, reducing the generation of aberration, and being beneficial to achieving high imaging quality.

[0069] In some embodiments, the focal length f3 of the third lens and the central thickness CT3 of the third lens satisfy: -255 < f3 / CT3 < -170. By satisfying the above conditional formula, the effective focal length and thickness of the third lens can be reasonably configured, so that the light enters the optical lens more gently, reducing the sensitivity of the optical lens, being beneficial to correcting the aberration generated by the optical lens, and thus being beneficial to improving the imaging quality of the optical lens.

[0070] In some embodiments, the maximum field of view FOV of the optical lens and the principal ray incident angle CRA at the maximum image height of the optical lens satisfy: 5.6 < FOV / CRA < 6. By satisfying the above conditional formula, the incident light of different field angles of the optical lens can enter the image sensor at an appropriate angle, thereby improving the photosensitive performance of the image sensor and the imaging quality of the optical lens.

[0071] In some embodiments, the clear aperture semi-diameter CSD31 of the object side surface of the third lens and the sagittal height SAG31 of the clear aperture of the object side surface of the third lens satisfy: 3.4 < CSD31 / SAG31 < 5.1. By satisfying the above conditional formula, by adjusting the surface shape of the edge region of the object side surface of the third lens, the ghost reflection energy can be reduced and the field curvature can be optimized, improving the imaging quality of the optical lens.

[0072] In some embodiments, the clear semi-diameter CSD22 of the image side of the second lens and the sag SAG22 of the clear semi-diameter of the image side of the second lens satisfy: 2.3 < CSD22 / SAG22 < 3. Meeting the above conditional formula, by adjusting the surface shape of the edge region of the image side of the second lens, it is beneficial to diverge the light rays in the edge field of view, and at the same time, the off-axis aberration of the edge field of view of the optical lens can be corrected, improving the imaging quality of the optical lens.

[0073] In some embodiments, the central thickness CT4 of the fourth lens and the sag SAG42 of the clear semi-diameter of the image side of the fourth lens satisfy: -2.5 < CT4 / SAG42 < -1.9. Meeting the above conditional formula, it is avoided that the central thickness of the fourth lens is too large or the image side is too curved while meeting the refractive power, which increases the manufacturing difficulty of the lens, thereby realizing the reduction of production costs.

[0074] In some embodiments, the optical lens satisfies the following conditional formula: 1.55 mm < f < 1.6 mm; 205° < FOV < 220°; 1 mm < EPDI < 1.1 mm; 12 mm < TTL < 12.5 mm; 1.5 ≤ Fno ≤ 1.55; 5.7 mm < IH < 6.1 mm; Meeting the above conditional formula, the optical lens has at least one or more advantages of short focal length, ultra-large field of view angle, large entrance pupil diameter, short total length, large aperture, large image plane, low distortion, and low sensitivity characteristics.

[0075] In some embodiments, the eight lenses in the optical lens can all adopt plastic lenses or adopt a structure with a combination of glass and plastic materials. Preferably, the optical lens of the present invention adopts a lens structure with a combination of eight glass and plastic materials, which can improve the thermal stability performance. Specifically, the first lens and the fifth lens can be made of glass lenses, and the second lens, the third lens, the fourth lens, the sixth lens, the seventh lens, and the eighth lens are all plastic lenses; adopting a glass-plastic hybrid structure can effectively reduce costs, correct aberrations, and reduce the volume, providing an optical lens product with higher cost performance.

[0076] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the first lens and the fifth lens in the optical lens provided by the present invention can adopt spherical lenses; the second lens, the third lens, the fourth lens, the sixth lens, the seventh lens, and the eighth lens can all adopt aspherical lenses.

[0077] In each embodiment of the present invention, when the lens adopts an aspherical lens, the surface shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0078] ;

[0079] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, F, G, and H are the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order surface coefficients, respectively.

[0080] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0081] Example 1

[0082] Please see Figure 1 The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane S19, the following components in sequence: a first lens L1, a second lens L2, a third lens L3, an aperture ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter G1.

[0083] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0084] The second lens L2 has negative optical power, its object side S3 is convex, and its image side S4 is concave.

[0085] The third lens L3 has negative optical power, its object side S5 is convex, and its image side S6 is concave.

[0086] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is convex.

[0087] The fifth lens L5 has positive optical power, its object side S9 is convex, and its image side S10 is convex.

[0088] The sixth lens L6 has negative optical power, its object side S11 is concave, and its image side S12 is concave.

[0089] The seventh lens L7 has positive optical power, its object side S13 is convex, and its image side S14 is convex.

[0090] The eighth lens L8 has negative optical power, its object side S15 is convex near the optical axis, and its image side S16 is concave.

[0091] The object-side surface S17 and the image-side surface S18 of filter G1 are both planar.

[0092] The imaging plane S19 is a plane.

[0093] The first lens L1 and the fifth lens L5 are glass spherical lenses; the second lens L2, the third lens L3, the fourth lens L4, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all plastic aspherical lenses.

[0094] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0095] Table 1-1

[0096]

[0097] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0098] Table 1-2

[0099]

[0100] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown.

[0101] Figure 2 The field curvature curve of the optical lens 100 in Embodiment 1 is shown, which represents the degree of curvature of light in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within -0.05 mm to 0.1 mm, indicating that the optical lens 100 can effectively correct the field curvature.

[0102] Figure 3 The figure shows the F-Theta distortion curve of the optical lens 100 in Embodiment 1, which represents the F-Theta distortion of light at different field of view angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within 0~10%, indicating that the optical lens 100 can correct distortion well.

[0103] Figure 4The diagram shows the axial aberration curve of the optical lens 100 in Embodiment 1, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the axial aberration offset is controlled within -0.02 mm to 0.04 mm, indicating that the optical lens 100 can correct axial aberration well.

[0104] Figure 5 The diagram shows the transverse chromatic aberration curve of the optical lens 100 in Embodiment 1. It represents the chromatic aberration of each wavelength relative to the center wavelength (0.555 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the figure, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -4 μm to 6 μm, indicating that the optical lens 100 can effectively correct chromatic aberration.

[0105] Example 2

[0106] Please see Figure 6 The figure shows a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S3 of the second lens L2 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

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

[0108] Table 2-1

[0109]

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

[0111] Table 2-2

[0112]

[0113] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown.

[0114] from Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.1mm to 0.05mm, indicating that the optical lens 200 can effectively correct the field curvature.

[0115] from Figure 8 As can be seen, the F-Theta distortion of the optical lens is controlled within 0~10%, indicating that the optical lens 200 can correct distortion well.

[0116] from Figure 9 As can be seen, the axial aberration offset is controlled within -0.02mm to 0.02mm, indicating that the optical lens 200 can correct the axial aberration well.

[0117] from Figure 10 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -4μm to 6μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0118] Example 3

[0119] Please see Figure 11 The figure shows a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S7 of the fourth lens L4 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0120] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0121] Table 3-1

[0122]

[0123] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0124] Table 3-2

[0125]

[0126] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens 300 are respectively as follows: Figure 12 , Figure 13 , Figure 14 , Figure 15 As shown.

[0127] from Figure 12 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.1mm to 0.05mm, indicating that the optical lens 300 can effectively correct the field curvature.

[0128] from Figure 13 As can be seen, the F-Theta distortion of the optical lens is controlled within 0~10%, indicating that the optical lens 300 can correct distortion well.

[0129] from Figure 14 As can be seen, the axial aberration offset is controlled within -0.02mm to 0.04mm, indicating that the optical lens 300 can correct axial aberration well.

[0130] from Figure 15 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -4μm to 5μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0131] Please refer to Table 4 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, principal ray incident angle CRA at the maximum image height, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0132] Table 4

[0133]

[0134] In summary, the optical lens provided by the present invention adopts an eight-element glass-plastic hybrid structure. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as ultra-wide angle, high pixel count, large aperture, low distortion, and high imaging quality.

[0135] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0136] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens, eight pieces of lenses in total, characterized in that, In order from the object side to the imaging surface along the optical axis, successively comprise: a first lens with negative focal power, the object side surface of which is convex, and the image side surface of which is concave; a second lens with negative focal power, the image side surface of which is concave; a third lens with negative focal power, the object side surface of which is convex, and the image side surface of which is concave; a fourth lens with positive focal power, the image side surface of which is convex; a fifth lens with positive focal power, the object side surface of which is convex, and the image side surface of which is convex; a sixth lens with negative focal power, the object side surface of which is concave, and the image side surface of which is concave; a seventh lens with positive focal power, the object side surface of which is convex, and the image side surface of which is convex; an eighth lens with negative focal power, the object side surface of which is convex at the near optical axis, and the image side surface of which is concave; wherein the combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: -1.6 < f123 / f < -1.2; the effective focal length f of the optical lens, the aperture value Fno of the optical lens and the total optical length TTL of the optical lens satisfy: 0.19 < fxFno / TTL < 0.

2.

2. The optical lens of claim 1, wherein, the combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -1.1 < f123 / f45678 < -0.

9.

3. The optical lens of claim 1, wherein, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -190 < f3 / f < -90; the object side surface curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: 2.7 < R5 / f < 2.

9.

4. The optical lens of claim 1, wherein, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 2.6 < f4 / f < 2.8; the image side surface curvature radius R8 of the fourth lens and the effective focal length f of the optical lens satisfy: -1.7 < R8 / f < -1.

4.

5. The optical lens of claim 1, wherein, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.9 < f5 / f < 2; the object side surface curvature radius R9 of the fifth lens and the image side surface curvature radius R10 of the fifth lens satisfy: 0.29 < (R9+R10) / (R9-R10) < 0.

45.

6. The optical lens of claim 1, wherein, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2.9 < f6 / f < -2; the object side surface curvature radius R11 of the sixth lens and the image side surface curvature radius R12 of the sixth lens satisfy: -0.5 < (R11+R12) / (R11-R12) < -0.

3.

7. The optical lens of claim 1, wherein, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.5 < f7 / f < 2.3; the image side surface curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: -1.5 < R14 / f < -0.

9.

8. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.6 < IH / f < 3.

8.

9. The optical lens of claim 1, wherein, A maximum field of view FOV of the optical lens and a chief ray angle of incidence CRA at a maximum image height of the optical lens satisfy: 5.6 < FOV / CRA < 6.

10. The optical lens of claim 1, wherein, A half chief ray diameter CSD11 of an object side surface of the first lens and a sagittal height SAG11 of the half chief ray diameter of the object side surface of the first lens satisfy: 2.5 < CSD11 / SAG11 < 3.2; a half chief ray diameter CSD12 of an image side surface of the first lens and a sagittal height SAG12 of the half chief ray diameter of the image side surface of the first lens satisfy: 1.35 < CSD12 / SAG12 < 1.45.

Images