Optical lens

Abstract

The invention provides an optical lens, which comprises eight lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power and a fifth lens with negative focal power from an object side to an imaging surface along an optical axis, the image side surface of the second lens is a convex surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface and the image side surface of the fourth lens are convex surfaces; the fifth lens has positive focal power, and the object side surface and the image side surface of the fifth lens are convex surfaces; the sixth lens has negative focal power, and the object side surface and the image side surface of the sixth lens are concave surfaces; the seventh lens has negative focal power; and the eighth lens has positive focal power. According to the optical lens provided by the invention, through reasonable configuration of the surface types of the lenses and reasonable matching of the focal power, the imaging quality of the optical lens is improved, the aberration is reduced, and the imaging quality of the optical lens is improved.

Description

Technical Field

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

[0002] With the continuous improvement of people's requirements for driving experience, in-vehicle application optical lenses are increasingly used in intelligent driving, and the status of in-vehicle optical lenses in the automotive-related industry is constantly rising.

[0003] Advanced Driver Assistance Systems (ADAS) play an important role in intelligent driving. It collects environmental information through various lenses and sensors to ensure the driving safety of the driver. In addition to requiring the optical lens to have a thin, light, short, and small shape and have characteristics such as high pixels and high resolution, the existing ADAS system lenses also require the optical lens to be able to clearly image under low illuminance conditions. Therefore, it is necessary to develop an optical lens with good imaging effects. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to provide an optical lens with the advantage of excellent imaging quality.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] An optical lens, comprising a total of eight lenses, which are sequentially arranged from the object side to the imaging surface along the optical axis:

[0007] A first lens with negative optical power, the image side of which is concave;

[0008] A second lens with positive optical power, the image side of which is convex;

[0009] A third lens with negative optical power, the object side of which is convex and the image side of which is concave;

[0010] A fourth lens with positive optical power, both the object side and the image side of which are convex;

[0011] A fifth lens with positive optical power, both the object side and the image side of which are convex;

[0012] A sixth lens with negative optical power, both the object side and the image side of which are concave;

[0013] A seventh lens with negative optical power;

[0014] An eighth lens with positive optical power;

[0015] For the optical lens, the effective focal length f and the true image height IH corresponding to the maximum field of view angle satisfy: 1.4 < IH / f < 2.2.

[0016] More preferably, the total optical length TTL of the optical lens and the effective focal length f satisfy: TTL / f < 5.5.

[0017] More preferably, the effective focal length f, the maximum field of view FOV, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 0.55 < (IH / 2) / (f × tan(FOV / 2)) < 0.9.

[0018] More preferably, the maximum field of view FOV of the optical lens and the f-number FNO satisfy: 35° < FOV / FNO < 80°.

[0019] More preferably, the effective focal length f of the optical lens and the back focal length BFL satisfy: 0.4 < BFL / f < 1.2.

[0020] More preferably, the maximum field of view FOV of the optical lens and the effective focal length f satisfy: 8.0 < FOV / f < 16.0.

[0021] More preferably, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: 0.5 < (R1 + R2) / (R1 - R2) < 1.5.

[0022] More preferably, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: (R5 + R6) / (R5 - R6) > 4.0.

[0023] More preferably, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis satisfy: 0.4 < ∑CT / TTL < 0.65.

[0024] More preferably, the maximum field of view FOV, the true image height IH corresponding to the maximum field of view, and the clear aperture D1 of the object side surface of the first lens of the optical lens satisfy: 0.5 < D1 / IH / tan(FOV / 2) < 1.9.

[0025] The optical lens provided by the present invention improves the imaging quality of the optical lens, reduces aberration, and improves the imaging quality of the optical lens through the reasonable configuration of each lens surface type and the reasonable matching of the optical power. Description of the Drawings

[0026] 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, where:

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

[0028] Figure 2 It is the field curvature curve graph of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 3 It is the F-Tanθ distortion curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 4 It is the relative illumination curve graph of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 5 It is the MTF curve graph of the optical lens in Embodiment 1 of the present invention.

[0032] Figure 6 It is the axial aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0033] Figure 7 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0034] Figure 8 It is the structural schematic diagram of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 9 It is the field curvature curve graph of the optical lens in Embodiment 2 of the present invention.

[0036] Figure 10 It is the F-Tanθ distortion curve of the optical lens in Embodiment 2 of the present invention.

[0037] Figure 11 It is the relative illumination curve graph of the optical lens in Embodiment 2 of the present invention.

[0038] Figure 12 It is the MTF curve graph of the optical lens in Embodiment 2 of the present invention.

[0039] Figure 13 It is the axial aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0040] Figure 14 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0041] Figure 15 It is the structural schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0042] Figure 16 It is the field curvature curve graph of the optical lens in Embodiment 3 of the present invention.

[0043] Figure 17 It is the F-Tanθ distortion curve of the optical lens in Embodiment 3 of the present invention.

[0044] Figure 18It is the relative illumination curve graph of the optical lens in Embodiment 3 of the present invention.

[0045] Figure 19 It is the MTF curve graph of the optical lens in Embodiment 3 of the present invention.

[0046] Figure 20 It is the axial aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0047] Figure 21 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0048] Figure 22 It is the structural schematic diagram of the optical lens in Embodiment 4 of the present invention.

[0049] Figure 23 It is the field curvature curve graph of the optical lens in Embodiment 4 of the present invention.

[0050] Figure 24 It is the F-Tanθ distortion curve of the optical lens in Embodiment 4 of the present invention.

[0051] Figure 25 It is the relative illumination curve graph of the optical lens in Embodiment 4 of the present invention.

[0052] Figure 26 It is the MTF curve graph of the optical lens in Embodiment 4 of the present invention.

[0053] Figure 27 It is the axial aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0054] Figure 28 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0055] Figure 29 It is the structural schematic diagram of the optical lens in Embodiment 5 of the present invention.

[0056] Figure 30 It is the field curvature curve graph of the optical lens in Embodiment 5 of the present invention.

[0057] Figure 31 It is the F-Tanθ distortion curve of the optical lens in Embodiment 5 of the present invention.

[0058] Figure 32 It is the relative illumination curve graph of the optical lens in Embodiment 5 of the present invention.

[0059] Figure 33 It is the MTF curve graph of the optical lens in Embodiment 5 of the present invention.

[0060] Figure 34 It is the axial aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0061] Figure 35 It is the vertical chromatic aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0062] Figure 36 It is the structural schematic diagram of the optical lens in Embodiment 6 of the present invention.

[0063] Figure 37 It is the field curvature curve graph of the optical lens in Embodiment 6 of the present invention.

[0064] Figure 38 It is the F-Tanθ distortion curve of the optical lens in Embodiment 6 of the present invention.

[0065] Figure 39 It is the relative illumination curve graph of the optical lens in Embodiment 6 of the present invention.

[0066] Figure 40 It is the MTF curve graph of the optical lens in Embodiment 6 of the present invention.

[0067] Figure 41 It is the axial aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0068] Figure 42 It is the vertical chromatic aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0069] Figure 43 It is the structural schematic diagram of the optical lens in Embodiment 7 of the present invention.

[0070] Figure 44 It is the field curvature curve graph of the optical lens in Embodiment 7 of the present invention.

[0071] Figure 45 It is the F-Tanθ distortion curve of the optical lens in Embodiment 7 of the present invention.

[0072] Figure 46 It is the relative illumination curve graph of the optical lens in Embodiment 7 of the present invention.

[0073] Figure 47 It is the MTF curve graph of the optical lens in Embodiment 7 of the present invention.

[0074] Figure 48 It is the axial aberration curve graph of the optical lens in Embodiment 7 of the present invention.

[0075] Figure 49 It is the vertical chromatic aberration curve graph of the optical lens in Embodiment 7 of the present invention.

[0076] Figure 50 It is the structural schematic diagram of the optical lens in Embodiment 8 of the present invention.

[0077] Figure 51 It is the field curvature curve graph of the optical lens in Embodiment 8 of the present invention.

[0078] Figure 52 It is the F-Tanθ distortion curve of the optical lens in Embodiment 8 of the present invention.

[0079] Figure 53 It is the relative illumination curve graph of the optical lens in Embodiment 8 of the present invention.

[0080] Figure 54 It is the MTF curve graph of the optical lens in Embodiment 8 of the present invention.

[0081] Figure 55 It is the axial aberration curve graph of the optical lens in Embodiment 8 of the present invention.

[0082] Figure 56 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 8 of the present invention.

[0083] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0084] To better understand the present application, more detailed descriptions of various aspects of the present application will be made with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application and do not limit the scope of the present 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.

[0085] It should be noted that in this specification, the expressions such as first, second, third, etc. are only used to distinguish one feature from another feature and do not represent any limitation on the features. Therefore, without departing from the teachings of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0086] In the drawings, for the sake of convenience of illustration, the thickness, size and shape of the lens have been slightly exaggerated. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only for illustration and are not drawn strictly to scale.

[0087] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object to be photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

[0088] It should also be understood that the terms "comprising", "comprises", "having", "include" and / or "including", when used in this specification, denote the presence of the stated features, elements and / or components, but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof. Further, when an expression such as "at least one of..." appears after a list of listed features, it modifies the entire list of listed features rather than individual elements in the list. Further, when describing embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the term "exemplary" is intended to refer to an example or illustration.

[0089] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in a common dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0090] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0091] The optical lens according to the embodiment of the present invention sequentially includes, along the optical axis from the object side to the imaging surface: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a filter and a protective glass. An aperture is provided between the third lens and the fourth lens, or between the second lens and the third lens, or between the first lens and the second lens.

[0092] In some embodiments, the first lens may have a negative focal power, and its image side is concave. The second lens may have a positive focal power, and its image side is convex. The third lens may have a negative focal power, its object side is convex, and its image side is concave. The fourth lens may have a positive focal power, and both its object side and image side are convex. The fifth lens may have a positive focal power, and both its object side and image side are convex. The sixth lens may have a negative focal power, and both its object side and image side are concave. The seventh lens may have a negative focal power. The eighth lens may have a positive focal power.

[0093] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 1.4 < IH / f < 2.2. Meeting the above range can not only achieve the wide-angle characteristic to meet the large-range shooting requirements, but also achieve the large image plane characteristic to improve the imaging quality of the optical lens.

[0094] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f satisfy: TTL / f < 5.5. Meeting the above range can effectively limit the length of the lens.

[0095] In some embodiments, the effective focal length f, the maximum field of view FOV, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 0.55 < (IH / 2) / (f × tan(FOV / 2)) < 0.9. Meeting the above requirements indicates that the optical distortion of the optical lens is well controlled, improving the resolution of the optical lens.

[0096] In some embodiments, the maximum field of view FOV of the optical lens and the f-number FNO satisfy: 35° < FOV / FNO < 80°. Meeting the above requirements is beneficial to expanding the field of view of the optical lens and increasing the aperture of the optical lens, facilitating the optical lens to obtain more scene information, meeting the requirements of large-range detection, and being beneficial to improving the problem of rapid decline in relative brightness in the edge field of view, thereby also being beneficial to obtaining more scene information.

[0097] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL satisfy: 0.4 < BFL / f < 1.2. Meeting the above range can reduce the interference of aberrations such as spherical aberration and coma, improve the resolution and clarity of imaging; and improve the stability of the optical lens.

[0098] In some embodiments, the maximum field of view FOV of the optical lens and the effective focal length f satisfy: 8.0 < FOV / f < 16.0. Meeting the above range enables the optical lens to capture more distant targets.

[0099] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: 0.5 < (R1 + R2) / (R1 - R2) < 1.5. Meeting the above range can control the light direction, reduce spherical aberration, correct coma, increase light utilization, and improve stability.

[0100] In some embodiments, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: (R5 + R6) / (R5 - R6) > 4.0. Meeting the above range can converge the light rays in the edge field of view, helping to optimize the imaging performance under low-light conditions and providing better image brightness and contrast.

[0101] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis respectively satisfy: 0.4 < ∑CT / TTL < 0.65. Meeting the above range can compress the total length of the optical system, making the structure of the system more compact.

[0102] In some embodiments, the maximum field of view (FOV) of the optical lens, the true image height (IH) corresponding to the maximum field of view, and the clear aperture (D1) of the object side surface of the first lens satisfy: 0.5 < D1 / IH / tan(FOV / 2) < 1.9. Meeting the above range can ensure the balance among the size of the optical lens, the field of view, and the image plane.

[0103] In some embodiments, the focal length (f1) of the first lens and the effective focal length (f) of the optical lens satisfy: -1.7 < f1 / f < -1.0. Meeting the above range can endow the first lens with an appropriate negative optical power, enabling the balance of the working aperture of the first lens with the image plane size and the field of view relationship.

[0104] In some embodiments, the focal length (f2) of the second lens and the effective focal length (f) of the optical lens satisfy: 3.0 < f2 / f < 10.0. Meeting the above range can endow the second lens with an appropriate positive optical power, making the light path stable, which is beneficial to balancing the aberration brought by the negative refractive power of the first lens, that is, it can correct the marginal aberration of the optical lens and improve the imaging resolution.

[0105] In some embodiments, the focal length (f3) of the third lens and the effective focal length (f) of the optical lens satisfy: f3 / f < -5.0. Meeting the above range can endow the third lens with a negative optical power, which is beneficial to the smooth transition of light and balances various aberrations generated by the third lens itself, thus improving the imaging quality of the optical system.

[0106] In some embodiments, the effective focal length (f) of the optical lens and the focal length (f4) of the fourth lens satisfy: 1.0 < f4 / f < 2.5. Meeting the above range can endow the fourth lens with an appropriate positive optical power, which is beneficial to improving the light converging ability of the optical lens. At the same time, it can balance the aberration of the optical lens and improve the imaging quality of the optical lens.

[0107] In some embodiments, the effective focal length (f) of the optical lens and the focal length (f5) of the fifth lens satisfy: 1.0 < f5 / f < 2.0. Meeting the above range can endow the fifth lens with an appropriate positive optical power, which is beneficial to improving the light converging ability of the optical lens. At the same time, it can balance the aberration of the optical lens and improve the imaging quality of the optical lens.

[0108] In some embodiments, the effective focal length (f) of the optical lens and the focal length (f6) of the sixth lens satisfy: -3.0 < f6 / f < -0.5. Meeting the above range can endow the sixth lens with an appropriate negative optical power, making the light path transition smoothly and improving the imaging quality of the optical lens.

[0109] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: f7 / f < -1.0. Satisfying the above range can make the seventh lens have a negative optical power, which is beneficial to increasing the imaging area of the optical lens and improving the imaging quality of the optical lens.

[0110] In some embodiments, the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: f8 / f > 1.0. Satisfying the above range can make the eighth lens have a positive optical power, balance various aberrations, and improve the imaging quality of the optical lens.

[0111] In some embodiments, the object-side curvature radius R7 of the fourth lens and the image-side curvature radius R8 of the fourth lens satisfy: -8.0 < R7 / R8 < -0.3. Satisfying the above range can reduce the coma introduced by the fourth lens, correct various aberrations of the optical lens at the same time, and improve the imaging quality of the optical lens.

[0112] In some embodiments, the object-side curvature radius R9 of the fifth lens and the image-side curvature radius R12 of the sixth lens satisfy: -35.0 < (R9 + R12) / (R9 - R12) < -1.2. Satisfying the above range can converge the marginal field light rays and improve the relative illumination of the optical lens.

[0113] In some embodiments, the fifth lens and the sixth lens can be glued together to form a glued lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberrations of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing technology difficulty of the optical lens and improving the assembly yield of the optical lens.

[0114] To make the system have better optical performance, multiple aspherical lenses are used in the lens, and the shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0115]

[0116] where z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the conic coefficient, and A, B, C, D, E, F are the second-order, fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients respectively.

[0117] The present invention will be further described below with reference to multiple embodiments. In each embodiment, the thickness, curvature radius, and material selection of each lens in the optical lens are somewhat different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following embodiments. Any other changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention shall be regarded as equivalent replacement methods and shall be included within the protection scope of the present invention.

[0118] Embodiment 1

[0119] Please refer to Figure 1 , which shows a schematic structural diagram of the optical lens provided in Embodiment 1 of the present invention. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a first lens L1, a second lens L2, a third lens L3, a diaphragm ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a filter G1, and a protective glass G2.

[0120] The first lens L1 has a negative optical power, and its object side S1 and image side S2 are both concave surfaces;

[0121] The second lens L2 has a positive optical power, its object side S3 is a concave surface, and its image side S4 is a convex surface;

[0122] The third lens L3 has a negative optical power, its object side S5 is a convex surface, and its image side S6 is a concave surface;

[0123] Diaphragm ST;

[0124] The fourth lens L4 has a positive optical power, and its object side S7 and image side S8 are both convex surfaces;

[0125] The fifth lens L5 has a positive optical power, and its object side S9 and image side S10 are both convex surfaces;

[0126] The sixth lens L6 has a negative optical power, and its object side S10 and image side S11 are both concave surfaces;

[0127] The fifth lens L5 and the sixth lens L6 form a cemented lens group, that is, the cemented surface of the image side of the fifth lens L5 and the object side of the sixth lens L6 is S10;

[0128] The seventh lens L7 has a negative optical power, its object side S12 is a concave surface, and its image side S13 is a convex surface;

[0129] The eighth lens L8 has a positive optical power, and its object side S14 and image side S15 are both convex surfaces;

[0130] The object side S16 and image side S17 of the filter G1 are both flat surfaces;

[0131] Both the object side S18 and the image side S19 of the protective glass G2 are flat surfaces;

[0132] The imaging surface S20 is a flat surface.

[0133] The relevant parameters of each lens in the optical lens of Embodiment 1 are shown in Table 1-1.

[0134] Table 1-1

[0135]

[0136] The surface type parameters of the aspherical lens in the optical lens of Embodiment 1 are shown in Table 1-2.

[0137] Table 1-2

[0138]

[0139]

[0140] In this embodiment, the field curvature curve, F-Tanθ distortion curve, relative illumination curve, MTF curve, axial aberration curve, and lateral chromatic aberration curve of the optical lens are respectively as Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 shown.

[0141] Figure 2 shows the field curvature curve of Embodiment 1, which represents the bending degree of light rays of different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08 mm to 0.06 mm, indicating that the optical lens can correct the field curvature well.

[0142] Figure 3 shows the F-Tanθ distortion curve of Embodiment 1, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging surface. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -40% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0143] Figure 4The relative illuminance curve of Embodiment 1 is shown, which represents the relative illuminance values at different field angles on the imaging surface. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illuminance (unit: %). It can be seen from the figure that the relative illuminance value of the optical lens is still greater than 70% at the maximum semi-field angle, indicating that the optical lens has good relative illuminance.

[0144] Figure 5 The MTF (Modulation Transfer Function) curve graph of Embodiment 1 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.4 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve decreases uniformly and smoothly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0145] Figure 6 The axial aberration curve graph of Embodiment 1 is shown, which represents the aberration on the optical axis at the imaging surface for each wavelength. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -30 μm to 10 μm, indicating that the optical lens can correct the axial aberration well.

[0146] Figure 7 The lateral chromatic aberration curve graph of Embodiment 1 is shown, which represents the chromatic aberration at different image heights on the imaging surface for each wavelength relative to the central wavelength (0.55 μm). The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1.5 μm to 2.5 μm, indicating that the optical lens can correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane extremely well.

[0147] Embodiment 2

[0148] Please refer to Figure 8 , which shows the structural schematic diagram of the optical lens provided in Embodiment 2 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main difference lies in that: the object side surface S3 of the second lens L2 is a convex surface, and there are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface.

[0149] The relevant parameters of each lens in the optical lens of Embodiment 2 are shown in Table 2-1.

[0150] Table 2-1

[0151]

[0152] The surface shape parameters of the aspherical lens of the optical lens in Embodiment 2 are shown in Table 2-2.

[0153] Table 2-2

[0154]

[0155]

[0156] In this embodiment, the field curvature curve, F-Tanθ distortion curve, relative illumination curve, MTF curve, axial aberration curve, and lateral chromatic aberration curve of the optical lens are respectively as Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 13 , Figure 14 shown.

[0157] Figure 9 shows the field curvature curve of Embodiment 2, which represents the bending degree of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08 mm to 0.04 mm, indicating that the optical lens can correct the field curvature well.

[0158] Figure 10 shows the F-Tanθ distortion curve of Embodiment 2, which represents the F-Tanθ distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -40% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0159] Figure 11 shows the relative illumination curve of Embodiment 2, which represents the relative illumination values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 70% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0160] Figure 12The MTF (Modulation Transfer Function) curve of Example 2 is shown, which represents the modulation of lens imaging at different spatial frequencies for each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this example is above 0.4 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve decreases uniformly and smoothly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0161] Figure 13 The axial aberration curve of Example 2 is shown, which represents the aberration on the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -15 μm to 10 μm, indicating that the optical lens can correct the axial aberration well.

[0162] Figure 14 The lateral chromatic aberration curve of Example 2 is shown, which represents the chromatic aberration at different image heights on the imaging plane for each wavelength relative to the central wavelength (0.55 μm). The horizontal axis represents the lateral chromatic aberration value (unit: μm) of each wavelength relative to the central wavelength, and the vertical axis represents the normalized field of view angle. It can be seen from the figure that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -2 μm to 3 μm, indicating that the optical lens can correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane extremely well.

[0163] Example 3

[0164] Please refer to Figure 15 , which shows the structural schematic diagram of the optical lens provided in Embodiment 3 of the present invention. The optical lens of this example is substantially the same as that of Example 1, and the main differences are as follows: The object side S1 of the first lens L1 is a convex surface, and the object side S3 of the second lens L2 is a convex surface. There are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface type.

[0165] The relevant parameters of each lens in the optical lens of Example 3 are shown in Table 3-1.

[0166] Table 3-1

[0167]

[0168] The surface type parameters of the aspheric lenses in the optical lens of Example 3 are shown in Table 3-2.

[0169] Table 3-2

[0170]

[0171]

[0172] In this embodiment, the field curvature curve graph, F-Tanθ distortion curve, relative illuminance curve graph, MTF curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens are respectively as Figure 16 , Figure 17 , Figure 18 , Figure 19 , Figure 20 , Figure 21 shown.

[0173] Figure 16 shows the field curvature curve of Embodiment 3, which represents the bending degree of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.04 mm to 0.02 mm, indicating that the optical lens can correct the field curvature well.

[0174] Figure 17 shows the F-Tanθ distortion curve of Embodiment 3, which represents the F-Tanθ distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -15% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0175] Figure 18 shows the relative illuminance curve of Embodiment 3, which represents the relative illuminance values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illuminance (unit: %). It can be seen from the figure that the relative illuminance value of the optical lens is still greater than 70% at the maximum semi-field angle, indicating that the optical lens has good relative illuminance.

[0176] Figure 19 shows the MTF (Modulation Transfer Function) curve graph of Embodiment 3, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value in this embodiment is above 0.4 within the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve smoothly decreases uniformly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0177] Figure 20The axial aberration curve of Example 3 is shown, which represents the aberration on the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -5 μm to 10 μm, indicating that the optical lens can correct the axial aberration well.

[0178] Figure 21 The lateral chromatic aberration curve of Example 3 is shown, which represents the chromatic aberration at different image heights on the imaging plane for each wavelength relative to the central wavelength (0.55 μm). The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm to 2 μm, indicating that the optical lens can correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane extremely well.

[0179] Example 4

[0180] Please refer to Figure 22 , which shows the structural schematic diagram of the optical lens provided in Embodiment 4 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main differences are as follows: The aperture stop ST is disposed between the second lens L2 and the third lens L3, the object side surface S14 of the eighth lens L8 is a concave surface, and there are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface.

[0181] The relevant parameters of each lens in the optical lens of Example 4 are shown in Table 4-1.

[0182] Table 4-1

[0183]

[0184] The surface type parameters of the aspheric lenses in the optical lens of Example 4 are shown in Table 4-2.

[0185] Table 4-2

[0186]

[0187]

[0188] In this embodiment, the field curvature curve, F-Tanθ distortion curve, relative illumination curve, MTF curve, axial aberration curve, and lateral chromatic aberration curve of the optical lens are respectively as Figure 23 , Figure 24 , Figure 25 , Figure 26 , Figure 27 , Figure 28 shown.

[0189] Figure 23The field curvature curve of Example 4 is shown, which represents the bending degree of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12 mm to 0.06 mm, indicating that the optical lens can correct the field curvature well.

[0190] Figure 24 The F-Tanθ distortion curve of Example 4 is shown, which represents the F-Tanθ distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -50% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0191] Figure 25 The relative illumination curve of Example 4 is shown, which represents the relative illumination values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 60% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0192] Figure 26 The MTF (Modulation Transfer Function) curve graph of Example 4 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.2 within the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases uniformly and smoothly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0193] Figure 27 The axial aberration curve graph of Example 4 is shown, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -40 μm to 20 μm, indicating that the optical lens can correct the axial aberration well.

[0194] Figure 28The vertical chromatic aberration curve diagram of Embodiment 4 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the vertical chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3 μm to 3 μm, indicating that this optical lens can excellently correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0195] Embodiment 5

[0196] Please refer to Figure 29 , which shows the structural schematic diagram of the optical lens provided in Embodiment 5 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main differences are as follows: The aperture stop ST is arranged between the second lens L2 and the third lens L3. The object side surface S3 of the second lens L2 is a convex surface, the image side surface S13 of the seventh lens L7 is a concave surface, and the object side surface S14 of the eighth lens L8 is a concave surface. There are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface type.

[0197] The relevant parameters of each lens in the optical lens of Embodiment 5 are shown in Table 5-1.

[0198] Table 5-1

[0199]

[0200] The surface type parameters of the aspheric lenses in the optical lens of Embodiment 5 are shown in Table 5-2.

[0201] Table 5-2

[0202]

[0203]

[0204] In this embodiment, the field curvature curve diagram, F-Tanθ distortion curve, relative illuminance curve diagram, MTF curve diagram, axial aberration curve diagram, and vertical chromatic aberration curve diagram of the optical lens are respectively as Figure 30 , Figure 31 , Figure 32 , Figure 33 , Figure 34 , Figure 35 shown.

[0205] Figure 30The field curvature curve of Example 5 is shown, which represents the bending degree of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.06 mm to 0.03 mm, indicating that the optical lens can correct the field curvature well.

[0206] Figure 31 The F-Tanθ distortion curve of Example 5 is shown, which represents the F-Tanθ distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -35% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the expanded image.

[0207] Figure 32 The relative illumination curve of Example 5 is shown, which represents the relative illumination values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 65% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0208] Figure 33 The MTF (Modulation Transfer Function) curve graph of Example 5 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.4 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve decreases uniformly and smoothly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0209] Figure 34 The axial aberration curve graph of Example 5 is shown, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -5 μm to 12 μm, indicating that the optical lens can correct the axial aberration well.

[0210] Figure 35The vertical chromatic aberration curve of Example 5 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.55 μm) at different image heights on the imaging surface. The horizontal axis represents the vertical chromatic aberration value (unit: μm) of each wavelength relative to the central wavelength, and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm to 2 μm, indicating that the optical lens can excellently correct the chromatic aberration of the edge field and the secondary spectrum of the entire image plane.

[0211] Example 6

[0212] Please refer to Figure 36 , which shows the schematic structural diagram of the optical lens provided in Embodiment 6 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main differences are as follows: The aperture stop ST is disposed between the second lens L2 and the third lens L3. The image side surface S13 of the seventh lens L7 is a concave surface, and the object side surface S14 of the eighth lens L8 is a concave surface. The optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface type are different.

[0213] The relevant parameters of each lens in the optical lens of Example 6 are shown in Table 6-1.

[0214] Table 6-1

[0215]

[0216] The surface type parameters of the aspheric lenses of the optical lens in Example 6 are shown in Table 6-2.

[0217] Table 6-2

[0218]

[0219]

[0220] In this embodiment, the field curvature curve, F-Tanθ distortion curve, relative illuminance curve, MTF curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens are respectively as Figure 37 , Figure 38 , Figure 39 , Figure 40 , Figure 41 , Figure 42 shown.

[0221] Figure 37 The field curvature curve of Example 6 is shown, which represents the bending degree of light rays of different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12 mm to 0.03 mm, indicating that the optical lens can well correct the field curvature.

[0222] Figure 38 The F-Tanθ distortion curve of Example 6 is shown, which represents the F-Tanθ distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -45% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0223] Figure 39 The relative illumination curve of Example 6 is shown, which represents the relative illumination values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 60% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0224] Figure 40 The MTF (Modulation Transfer Function) curve graph of Example 6 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.2 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve smoothly decreases uniformly from the center to the edge field of view, and it has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0225] Figure 41 The axial aberration curve graph of Example 6 is shown, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -40 μm to 30 μm, indicating that the optical lens can correct the axial aberration well.

[0226] Figure 42 The lateral chromatic aberration curve graph of Example 6 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -4 μm to 4 μm, indicating that the optical lens can correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane extremely well.

[0227] Example 7

[0228] Please refer to Figure 43, which shows a schematic structural diagram of the optical lens provided in Embodiment 7 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main differences are as follows: The aperture stop ST is disposed between the second lens L2 and the third lens L3. The object side surface S3 of the second lens L2 is a convex surface, and the image side surface S13 of the seventh lens L7 is a concave surface. There are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface type.

[0229] The relevant parameters of each lens in the optical lens of Embodiment 7 are shown in Table 7-1.

[0230] Table 7-1

[0231]

[0232] The surface type parameters of the aspheric lenses in the optical lens of Embodiment 7 are shown in Table 7-2.

[0233] Table 7-2

[0234] Plane number K A B C D E F S5 -3.74E+00 0.00E+00 -6.21E-04 -7.66E-06 1.77E-07 -9.49E-10 -3.56E-12 S6 1.25E+00 0.00E+00 -8.04E-04 -4.38E-06 1.69E-07 -2.28E-09 2.79E-12 S7 -3.00E+01 0.00E+00 2.26E-04 7.13E-06 -2.29E-07 2.78E-09 -1.30E-11 S8 -7.87E-01 0.00E+00 -2.58E-05 2.16E-06 -6.42E-08 1.71E-09 -1.24E-11 S14 6.17E-01 0.00E+00 5.14E-05 4.00E-06 -1.23E-07 4.10E-09 -3.70E-11 S15 1.78E+00 0.00E+00 2.57E-04 6.06E-06 -1.82E-07 6.82E-09 -6.55E-11

[0235] In this embodiment, the field curvature curve graph, F-Tanθ distortion curve graph, relative illuminance curve graph, MTF curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens are respectively as Figure 44 , Figure 45 , Figure 46 , Figure 47 , Figure 48 , Figure 49 shown.

[0236] Figure 44 shows the field curvature curve of Embodiment 7, which represents the bending degree of light rays of different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12 mm to 0.12 mm, indicating that the optical lens can correct the field curvature well.

[0237] Figure 45 shows the F-Tanθ distortion curve of Embodiment 7, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -40% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the unfolded image.

[0238] Figure 46The relative illuminance curve of Example 7 is shown, which represents the relative illuminance values at different field angles on the imaging plane. The horizontal axis represents the semi-field angle (unit: °), and the vertical axis represents the relative illuminance (unit: %). It can be seen from the figure that the relative illuminance value of the optical lens is still greater than 60% at the maximum semi-field angle, indicating that the optical lens has good relative illuminance.

[0239] Figure 47 The MTF (Modulation Transfer Function) curve graph of Example 7 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.2 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve smoothly decreases uniformly from the center to the edge field of view, and it has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0240] Figure 48 The axial aberration curve graph of Example 7 is shown, which represents the aberration on the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -15 μm to 25 μm, indicating that the optical lens can correct the axial aberration well.

[0241] Figure 49 The lateral chromatic aberration curve graph of Example 7 is shown, which represents the chromatic aberration at different image heights on the imaging plane for each wavelength relative to the central wavelength (0.55 μm). The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -4 μm to 5 μm, indicating that the optical lens can excellently correct the chromatic aberration in the edge field of view and the secondary spectrum of the entire image plane.

[0242] Example 8

[0243] Please refer to Figure 50 , which shows the structural schematic diagram of the optical lens provided in Embodiment 8 of the present invention. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the main differences are as follows: The aperture stop ST is disposed between the first lens L1 and the second lens L2. The object side surface S3 of the second lens L2 is convex. The object side surface S12 of the seventh lens L7 is convex. The image side surface S13 of the seventh lens L7 is concave. The image side surface S15 of the eighth lens L8 is concave. There are differences in the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface.

[0244] The relevant parameters of each lens in the optical lens of Example 8 are shown in Table 8-1.

[0245] Table 8-1

[0246]

[0247]

[0248] The surface parameters of the aspherical lens of the optical lens in Example 8 are shown in Table 8-2.

[0249] Table 8-2

[0250] Plane number K A B C D E F S5 8.45E+00 0.00E+00 -3.46E-04 -4.22E-07 -3.76E-08 4.42E-10 -2.99E-12 S6 -8.57E+00 0.00E+00 -9.55E-05 -3.74E-06 5.36E-09 3.21E-10 -1.22E-12 S7 3.35E-01 0.00E+00 -2.28E-05 -1.03E-06 -6.47E-09 4.97E-10 -4.22E-12 S8 -7.34E-01 0.00E+00 5.45E-05 2.76E-07 1.90E-08 -1.10E-10 -1.10E-12 S12 0.00E+00 0.00E+00 -1.84E-04 1.08E-05 -1.70E-07 8.26E-10 -4.04E-12 S13 0.00E+00 0.00E+00 -1.60E-03 -1.43E-05 5.65E-07 -4.09E-09 -2.37E-11 S14 1.94E+00 0.00E+00 -5.61E-05 -5.11E-05 4.71E-07 1.50E-08 -2.90E-10 S15 2.98E+01 0.00E+00 1.40E-03 -1.85E-05 1.13E-07 2.30E-08 -4.69E-10

[0251] In this embodiment, the field curvature curve, F-Tanθ distortion curve, relative illumination curve, MTF curve, axial aberration curve, and lateral chromatic aberration curve of the optical lens are respectively as Figure 51 , Figure 52 , Figure 53 , Figure 54 , Figure 55 , Figure 56 shown.

[0252] Figure 51 shows the field curvature curve of Example 8, which represents the bending degree of light rays of different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08 mm to 0.04 mm, indicating that the optical lens can correct the field curvature well.

[0253] Figure 52 shows the F-Tanθ distortion curve of Example 8, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -15% to 0, and the image compression in the edge angle region is relatively gentle, effectively improving the clarity of the expanded image.

[0254] Figure 53 shows the relative illumination curve of Example 8, which represents the relative illumination values at different field angles on the imaging plane. The horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 60% at the maximum half field angle, indicating that the optical lens has good relative illumination.

[0255] Figure 54The MTF (Modulation Transfer Function) curve of Example 8 is shown, which represents the modulation of the lens imaging at different spatial frequencies in each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.3 within the entire field of view. In the range of 0 - 160 lp / mm, the MTF curve decreases uniformly and smoothly from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0256] Figure 55 The axial aberration curve of Example 8 is shown, which represents the aberration on the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -20 μm to 15 μm, indicating that the optical lens can correct the axial aberration well.

[0257] Figure 56 The lateral chromatic aberration curve of Example 8 is shown, which represents the chromatic aberration at different image heights on the imaging plane for each wavelength relative to the central wavelength (0.55 μm). The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field of view angle. It can be seen from the figure that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -3 μm to 5 μm, indicating that the optical lens can correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane extremely well.

[0258] Please refer to Table 9 for the optical characteristics corresponding to the above embodiments, including the effective focal length f, the total optical length TTL, the f-number FNO, the true image height IH, the chief ray angle of incidence CRA, the clear aperture D1 of the object side surface of the first lens, the maximum field of view FOV, and the values corresponding to each conditional formula in each embodiment.

[0259] Table 9

[0260]

[0261]

[0262] Based on the above embodiments, the optical lens provided by the present invention improves the imaging quality of the optical lens, reduces aberration, and improves the imaging quality of the optical lens through the reasonable configuration of each lens surface type and the reasonable matching of the optical power.

[0263] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0264] The above-described embodiments merely represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. An optical lens, consisting of eight lenses in total, characterized in that, From the object side to the imaging surface along the optical axis, it successively includes: A first lens with a negative optical power, whose image side is concave; A second lens with a positive optical power, whose image side is convex; A third lens with a negative optical power, whose object side is convex and image side is concave; A fourth lens with a positive optical power, whose object side and image side are both convex; A fifth lens with a positive optical power, whose object side and image side are both convex; A sixth lens with a negative optical power, whose object side and image side are both concave; A seventh lens with a negative optical power; An eighth lens with a positive optical power; The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 1.4 < IH / f < 2.

2.

2. The optical lens according to claim 1, wherein The overall optical length TTL of the optical lens and the effective focal length f satisfy: TTL / f < 5.

5.

3. The optical lens according to claim 1, characterized in that, The effective focal length f, the maximum field of view angle FOV, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.55 < (IH / 2) / (f×tan(FOV / 2)) < 0.

9.

4. The optical lens according to claim 1, wherein The maximum field of view angle FOV of the optical lens and the aperture value FNO satisfy: 35° < FOV / FNO < 80°.

5. The optical lens according to claim 1, wherein The effective focal length f of the optical lens and the back focal length BFL satisfy: 0.4 < BFL / f < 1.

2.

6. The optical lens according to claim 1, wherein The maximum field of view angle FOV of the optical lens and the effective focal length f satisfy: 8.0 < FOV / f < 16.

0.

7. The optical lens according to claim 1, characterized in that, The curvature radius R1 of the object side of the first lens and the curvature radius R2 of the image side of the first lens satisfy: 0.5 < (R1+R2) / (R1-R2) < 1.

5.

8. The optical lens according to claim 1, wherein The curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: (R5+R6) / (R5-R6) > 4.

0.

9. The optical lens according to claim 1, characterized in that The overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis respectively satisfy: 0.4 < ∑CT / TTL < 0.

65.

10. The optical lens according to claim 1, wherein The maximum field of view angle FOV, the true image height IH corresponding to the maximum field of view angle, and the clear aperture D1 of the object side of the first lens of the optical lens satisfy: 0.5 < D1 / IH / tan(FOV / 2) < 1.9.

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