Optical lens

Abstract

The present invention provides an optical lens, which consists of seven lenses in total. It is characterized in that, along the optical axis from the object side to the imaging surface, they are successively: a first lens with a negative optical power, whose object side is convex and image side is concave; a second lens with a negative optical power, whose object side is convex and image side is concave; a third lens with a negative optical power, whose object 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 positive optical power, whose object side and image side are both convex; the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 4.2 < IH / f.

Description

Technical Field

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

[0002] With the development of automotive intelligence, the vehicle's assisted driving system has been gradually improved. As one of the main tools for the assisted driving system to obtain external information, the imaging quality of in-vehicle lenses directly affects the performance of the assisted driving system.

[0003] In order to accurately obtain external information, in-vehicle lenses need to be paired with chips of larger size and higher resolution. Therefore, in-vehicle lenses need to have high resolution capabilities. In addition, for safety considerations, in-vehicle lenses also need to have high stability to adapt to various harsh environments and avoid problems such as a decrease in the imaging performance of in-vehicle lenses when used in different environments. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to propose an optical lens, which has the advantages of a large field of view and a large image plane.

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

[0006] An optical lens, comprising seven lenses in total, characterized in that, along the optical axis from the object side to the imaging plane, they are in sequence:

[0007] A first lens with negative optical power, having a convex object side and a concave image side;

[0008] A second lens with negative optical power, having a convex object side and a concave image side;

[0009] A third lens with negative optical power, having a concave object side;

[0010] A fourth lens with positive optical power, having convex object and image sides;

[0011] A fifth lens with positive optical power, having convex object and image sides;

[0012] A sixth lens with negative optical power, having concave object and image sides;

[0013] A seventh lens with positive optical power, having convex object and image sides;

[0014] For the optical lens, the effective focal length f and the true image height IH corresponding to the maximum field of view angle satisfy: 4.2 < IH / f.

[0015] Preferably, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 3.0 < TTL / IH < 5.0.

[0016] Preferably, the entrance pupil diameter EPD of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 7.5 < IH / EPD < 11.0.

[0017] Preferably, the true image height IH corresponding to the maximum field of view angle of the optical lens and the true image height IH corresponding to the maximum half field of view angle h satisfy: 0.38 < IH h / IH < 0.45.

[0018] Preferably, the effective focal length f, the maximum field of view angle θ, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.2 < (IH / 2) / (f×(θ / 2)) < 1.6.

[0019] Preferably, the maximum field of view angle FOV of the optical lens and the incident angle CRA of the chief ray of the maximum field of view angle on the image plane satisfy: 4.5 < (FOV / 2) / CRA < 5.5.

[0020] Preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -3.0.

[0021] Preferably, the effective focal length f of the optical lens and the curvature radius R1 of the object side surface and the curvature radius R2 of the image side surface of the first lens respectively satisfy: 12.0 < R1 / f, R2 / f < 6.0.

[0022] Preferably, the sagittal height Sag3 and the clear aperture semi-diameter d3 of the object side surface of the second lens and the sagittal height Sag4 and the clear aperture semi-diameter d4 of the image side surface of the second lens satisfy: 0.28 < (Sag3 / d3) / (Sag4 / d4) < 0.40.

[0023] Preferably, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis respectively satisfy: 0.50 < ∑CT / TTL < 0.70.

[0024] Compared with the prior art, the beneficial effects of the present invention are: by reasonably matching the lens shapes and the combination of optical powers between the lenses, the advantages of both a large field of view and a large image plane are achieved.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present invention. Brief 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 description of the embodiments in conjunction with the following drawings, wherein:

[0027] Figure 1 Schematic structural diagram of the optical lens according to Embodiment 1 of the present invention.

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

[0029] Figure 3 F-Theta distortion curve graph of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 4 Relative illuminance curve graph of the optical lens in Embodiment 1 of the present invention.

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

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

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

[0034] Figure 8 Schematic structural diagram of the optical lens according to Embodiment 2 of the present invention.

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

[0036] Figure 10 F-Theta distortion curve graph of the optical lens in Embodiment 2 of the present invention.

[0037] Figure 11 Relative illuminance curve graph of the optical lens in Embodiment 2 of the present invention.

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

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

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

[0041] Figure 15 Schematic structural diagram of the optical lens according to Embodiment 3 of the present invention.

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

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

[0044] Figure 18 It 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. Detailed implementation manners

[0048] To better understand the present invention, more detailed descriptions will be made for various aspects of the present invention with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present invention and do not limit the scope of the present invention in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0049] It should be noted that in this specification, the expressions such as first, second, and third 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.

[0050] In the accompanying drawings, for the 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 examples and are not drawn strictly to scale.

[0051] 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.

[0052] It should also be understood that the terms "comprise", "comprising", "have", "including" and / or "containing", 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. In addition, 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. In addition, when describing embodiments of the present invention, the use of "may" means "one or more embodiments of the present invention". Also, the term "exemplary" is intended to refer to an example or illustration.

[0053] 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 invention 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.

[0054] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0055] The optical lens according to an embodiment of the present invention sequentially includes, from the object side to the image side: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, as well as a filter and a protective glass.

[0056] In some embodiments, the first lens may have a negative optical power, which is beneficial to reducing the inclination angle of the incident light, thereby effectively sharing the large field of view on the object side. The object side surface of the first lens is convex, and the image side surface is concave, which is beneficial to obtaining a larger field of view angle range. In addition, in practical applications, considering the outdoor installation and use environment of vehicle-mounted application lenses, the lens will be in harsh weather such as rain and snow. Setting the first lens as a meniscus shape with the convex surface facing the object side can facilitate the sliding of water droplets and the like, and can reduce the influence on the imaging of the lens. The first lens may have an aspherical mirror surface, which is beneficial to the large-angle resolution of the edge region of the optical lens and can improve the resolution of the edge field of view region.

[0057] In some embodiments, the second lens may have a negative optical power, capable of sharing the negative optical power at the front end of the optical lens, thereby facilitating the avoidance of excessive light deflection caused by over-concentration of the optical power of the first lens and reducing the difficulty of chromatic aberration correction of the optical lens. The object side of the second lens is convex and the image side is concave, which is beneficial to improving the light collection ability of the marginal field of view while reducing the working aperture of the second lens, thus facilitating the miniaturization of the volume at the rear end of the optical lens; in addition, it can effectively avoid the lateral chromatic aberration caused by excessive light deflection angle of the marginal field of view during the process of light transmission from the first lens to the second lens, reducing the difficulty of chromatic aberration correction of the optical lens.

[0058] In some embodiments, the third lens may 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. The object side of the third lens is concave, which is beneficial to converging the marginal light and effectively transmitting more light beams to the rear optical system, improving the imaging quality of the optical lens.

[0059] In some embodiments, the fourth lens may have a positive optical power, which is beneficial to reducing the light deflection angle and enabling the light to transition smoothly. Both the object side and the image side of the fourth lens are convex, which is beneficial to the smooth transition of the light path and balancing the spherical aberration generated by the fourth lens itself, improving the imaging quality of the optical lens.

[0060] In some embodiments, the fifth lens may have a positive optical power, which is beneficial to improving the light convergence ability of the marginal field of view, effectively controlling the overall optical length and reducing the volume of the optical lens, and thus facilitating the miniaturization of the optical lens. Both the object side and the image side of the fifth lens are convex, which is beneficial to the smooth transition of the light path and balancing the spherical aberration and coma generated by the fifth lens itself, improving the imaging quality of the optical lens.

[0061] In some embodiments, the sixth lens may 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. Both the object side and the image side of the sixth lens are concave, which is beneficial to balancing the astigmatism generated by the sixth lens itself, improving the imaging quality of the optical lens.

[0062] In some embodiments, the seventh lens may have a positive optical power, which is beneficial to suppressing the angle of incidence of the marginal field of view on the imaging surface, effectively transmitting more light beams to the imaging surface, and improving the imaging quality of the optical lens. Both the object side and the image side of the seventh lens are convex, which is beneficial to improving the relative illumination of the marginal field of view and avoiding the generation of vignetting, improving the imaging quality of the optical lens.

[0063] 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 aberration of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0064] In some embodiments, a diaphragm for restricting the light beam can be provided between the third lens and the fourth lens or between the fourth lens and the fifth lens. The diaphragm can be disposed near the object side surface of the fourth lens or the fifth lens, which can reduce the generation of ghosts in the optical lens and is beneficial to converging the light rays entering the optical system and reducing the rear port diameter of the optical lens.

[0065] In some embodiments, the aperture value FNO of the optical lens satisfies: FNO < 2.10. Meeting the above range can enable the optical lens to have a sufficiently large depth of field and meet the clear acquisition of long-distance information by the optical lens.

[0066] In some embodiments, the maximum field of view FOV of the optical lens satisfies: 190° ≤ FOV. Meeting the above range is beneficial to realizing the ultra-wide-angle characteristic, so as to be able to obtain more scene information and meet the requirements of large-range detection of the optical lens.

[0067] In some embodiments, the incident angle CRA of the principal ray of the maximum field of view of the optical lens on the image plane satisfies: 18° < CRA < 20°. Meeting the above range can make the optical lens have an appropriate allowable error range between the CRA and the CRA of the chip photosensitive element, and improve the adaptability of the optical lens to the image sensor.

[0068] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view satisfy: 3.0 < TTL / IH < 5.0. Meeting the above range is beneficial to achieving a balance between obtaining good imaging quality and miniaturized design of the optical lens, and can meet the requirements for the optical lens under different working conditions.

[0069] 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 satisfy: 4.2 < IH / f. Meeting the above range can not only realize the ultra-wide-angle characteristic to meet the large-range shooting requirements, but also realize the large image plane characteristic to improve the imaging quality of the optical system.

[0070] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f satisfy: 1.3 < BFL / f. Meeting the above range is beneficial to achieving a balance between obtaining good imaging quality and an easily assembled back focal length, ensuring the imaging quality of the optical lens while reducing the assembly process difficulty of the camera module.

[0071] In some embodiments, the maximum field of view angle FOV of the optical lens and the effective focal length f satisfy: 115° / mm < FOV / f < 150° / mm. Meeting the above range can, while obtaining a relatively large field of view angle, also reduce the deflection angle of the outgoing light rays, lower the sensitivity of the optical lens and the correction difficulty of various aberrations, thereby improving the imaging quality of the optical lens.

[0072] In some embodiments, the entrance pupil diameter EPD of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 7.5 < IH / EPD < 11.0. Meeting the above range can make the width of the light beam incident on the optical lens larger, improve the brightness of the optical lens at the image plane and avoid the generation of vignetting, and at the same time can increase the imaging area of the optical lens.

[0073] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the true image height IH corresponding to the maximum half field of view angle h satisfy: 0.38 < IH h / IH < 0.45. Meeting the above range can increase the proportion of the imaging range of the edge field of view in the entire imaging range. The larger the imaging range, the more pixels occupied on the corresponding chip surface, and thus more detailed information of the edge field of view can be obtained.

[0074] In some embodiments, the effective focal length f, the maximum field of view angle θ, and the true image height IH corresponding to the maximum half field of view angle of the optical lens satisfy: 1.2 < (IH / 2) / (f×(θ / 2)) < 1.6. Meeting the above range is beneficial to controlling the smooth change of the edge distortion of the optical lens, which is convenient for later restoration through software algorithms.

[0075] In some embodiments, the maximum field of view angle FOV of the optical lens and the incident angle CRA of the chief ray of the maximum field of view angle on the image plane satisfy: 4.5 < (FOV / 2) / CRA < 5.5. Meeting the above range can enable the incident light rays to enter the image sensor at an appropriate angle while the optical lens achieves a large field of view, thereby improving the photosensitive performance of the image sensor and the imaging quality of the optical lens.

[0076] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -14.0 < f1 / f < -9.0. Meeting the above range can make the first lens have an appropriate negative optical power, which is beneficial to reducing the inclination angle of the incident light rays, thereby effectively sharing the large field of view on the object side and at the same time being able to obtain a larger field of view angle range.

[0077] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -3.0. Meeting the above range can endow the second lens with an appropriate negative optical power, enabling it to share the negative optical power at the front end of the optical lens, thereby facilitating the avoidance of excessive light deflection caused by overly concentrated optical power of the first lens and reducing the difficulty of chromatic aberration correction of the optical lens.

[0078] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -15.0 < f3 / f < -5.0. Meeting the above range can endow the third lens with an appropriate negative optical power, which is beneficial to increasing the imaging area of the optical lens and improving the imaging quality of the optical lens.

[0079] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.0 < f4 / f < 6.0. Meeting the above range can endow the fourth lens with an appropriate positive optical power, which is beneficial to converging light while reducing the light deflection angle, enabling the light path to transition smoothly and improving the imaging quality of the optical lens.

[0080] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 2.0 < f5 / f < 3.5. Meeting the above range can endow the fifth lens with an appropriate positive optical power, which is beneficial to improving the ability to converge light in the peripheral field of view, effectively controlling the overall optical length and reducing the volume of the optical lens, and thus facilitating the miniaturization of the optical lens.

[0081] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.0 < f6 / f < -1.0. Meeting the above range can endow the sixth lens with an appropriate negative optical power, which is beneficial to increasing the imaging area of the optical lens and improving the imaging quality of the optical lens.

[0082] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.0 < f7 / f < 3.0. Meeting the above range can endow the seventh lens with an appropriate positive optical power, which is beneficial to suppressing the angle of incidence of the peripheral field of view on the imaging surface, effectively transmitting more light beams to the imaging surface, and improving the imaging quality of the optical lens.

[0083] In some embodiments, the effective focal length f of the optical lens and the combined focal length f of the fifth lens and the sixth lens 56 satisfy: -50.0 < f 56 / f < -5.5. Meeting the above range can make the cemented lens formed by the fifth lens and the sixth lens have an appropriate negative optical power, which is beneficial to balancing the chromatic aberration of the optical lens and improving the imaging quality of the optical lens.

[0084] In some embodiments, the effective focal length f of the optical lens, the curvature radius R1 of the object side surface of the first lens, and the curvature radius R2 of the image side surface respectively satisfy: 12.0 < R1 / f, R2 / f < 6.0. Meeting the above ranges is beneficial to achieving the ultra-wide-angle characteristic, so that more scene information can be obtained, meeting the requirements of the large-range detection of the optical lens.

[0085] In some embodiments, the sagittal height Sag3 and the clear aperture semi-diameter d3 of the object side surface of the second lens and the sagittal height Sag4 and the clear aperture semi-diameter d4 of the image side surface of the second lens satisfy: 0.28 < (Sag3 / d3) / (Sag4 / d4) < 0.40. Meeting the above ranges is beneficial to compressing the central field of view of the optical lens, making the imaging quality of the edge field of view better.

[0086] 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 sixth lens along the optical axis respectively satisfy: 0.50 < ∑CT / TTL < 0.70. Meeting the above ranges can effectively compress the total length of the optical lens, and is beneficial to the structural design and production process of the optical lens.

[0087] To enable the system to have better optical performance, multiple aspherical lenses are used in the lens, and the surface shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0088]

[0089] 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.

[0090] The present invention will be further described below with multiple embodiments. In each embodiment, the thickness, curvature radius, and material selection of each lens in the optical lens are partially different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only the 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 should be regarded as equivalent substitution methods and are included in the protection scope of the present invention.

[0091] Embodiment 1

[0092] 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 fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0093] The first lens L1 has a negative focal power. Its object side surface S1 is convex, and its image side surface S2 is concave.

[0094] The second lens L2 has a negative focal power. Its object side surface S3 is convex, and its image side surface S4 is concave.

[0095] The third lens L3 has a negative focal power. Its object side surface S5 is concave, and its image side surface S6 is convex.

[0096] The fourth lens L4 has a positive focal power. Its object side surface S7 and image side surface S8 are both convex.

[0097] The diaphragm ST;

[0098] The fifth lens L5 has a positive focal power. Its object side surface S9 and image side surface S10 are both convex.

[0099] The sixth lens L6 has a negative focal power. Its object side surface S11 and image side surface S12 are both concave.

[0100] The seventh lens L7 has a positive focal power. Its object side surface S13 and image side surface S14 are both convex.

[0101] The filter G1, whose object side surface S15 and image side surface S16 are both flat.

[0102] The protective glass G2, whose object side surface S17 and image side surface S18 are both flat.

[0103] The imaging surface S19 is flat;

[0104] The fifth lens L5 and the sixth lens L6 can be glued together to form a glued lens.

[0105] The relevant parameters of each lens in the optical lens in Embodiment 1 are shown in Table 1-1.

[0106] Table 1-1

[0107]

[0108]

[0109] The aspheric lens surface type parameters of the optical lens in Embodiment 1 are shown in Table 1-2.

[0110] Table 1-2

[0111] Plane number K A B C D E F S3 -5.00E+01 0.00E+00 1.38E-03 -7.22E-05 2.75E-06 -5.35E-08 4.11E-10 S4 -4.82E-01 0.00E+00 -2.26E-03 2.47E-04 -3.31E-05 1.96E-06 -4.55E-08 S5 1.49E-03 0.00E+00 -1.90E-05 -4.33E-05 2.17E-05 -1.20E-06 3.04E-08 S6 -1.84E+00 0.00E+00 -1.29E-04 -1.74E-05 4.60E-06 -2.15E-07 4.45E-09 S13 -1.71E+00 0.00E+00 -2.29E-03 5.68E-04 -7.24E-05 7.07E-06 -2.59E-07 S14 9.46E-01 0.00E+00 4.44E-03 -3.43E-04 1.29E-04 -1.40E-05 7.09E-07

[0112] Figure 2 The field curvature curve of Embodiment 1 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 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 ±0.05 mm, indicating that the optical lens can excellently correct the field curvature.

[0113] Figure 3 The F-Theta distortion curve of Embodiment 1 is shown, which represents the F-Theta distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Theta distortion (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Theta distortion of the optical lens is controlled within 0-24%, indicating that the F-Theta distortion of the optical lens is effectively controlled, which is beneficial for later restoration through software algorithms.

[0114] Figure 4 The relative illumination curve of Embodiment 1 is shown, 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 50% at the maximum half field angle, indicating that the optical lens has good relative illumination.

[0115] Figure 5 The modulation transfer function (MTF) curve 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 0.3 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 of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0116] Figure 6 The axial aberration curve of Embodiment 1 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 ±15 μm, indicating that the optical lens can well correct the axial aberration.

[0117] Figure 7The vertical chromatic aberration curve diagram of Embodiment 1 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 of view angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens can excellently correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0118] Embodiment 2

[0119] Please refer to Figure 8 , which shows the schematic structural diagram of the optical lens provided in Embodiment 2 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, and a filter G1 and a protective glass G2.

[0120] The first lens L1 has a negative optical power. Its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface;

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

[0122] The third lens L3 has a negative optical power. Its object side surface S5 and image side surface S6 are both concave surfaces;

[0123] Diaphragm ST;

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

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

[0126] The sixth lens L6 has a negative optical power. Its object side surface S11 and image side surface S12 are both concave surfaces;

[0127] The seventh lens L7 has a positive optical power. Its object side surface S13 and image side surface S14 are both convex surfaces;

[0128] Filter G1, whose object side surface S15 and image side surface S16 are both flat surfaces;

[0129] Protective glass G2, whose object side surface S17 and image side surface S18 are both flat surfaces;

[0130] The imaging surface S19 is a flat surface;

[0131] The fifth lens L5 and the sixth lens L6 can be glued together to form a cemented lens.

[0132] The relevant parameters of each lens in the optical lens of Embodiment 2 are shown in Table 2-1.

[0133] Table 2-1

[0134]

[0135]

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

[0137] Table 2-2

[0138] Plane number K A B C D E F S3 -2.77E+01 0.00E+00 -4.65E-04 4.02E-05 -2.93E-07 -1.54E-08 3.58E-10 S4 -9.03E-01 0.00E+00 -9.51E-03 1.32E-03 -1.75E-04 1.48E-05 -6.92E-07 S5 2.02E+01 0.00E+00 -1.33E-03 -5.93E-04 1.27E-04 -1.35E-05 7.91E-07 S6 2.64E+01 0.00E+00 6.94E-03 1.15E-03 8.44E-04 -9.49E-04 6.01E-04 S13 9.18E+00 0.00E+00 -9.09E-03 1.28E-03 7.08E-06 -2.92E-05 1.73E-06 S14 -2.31E+00 0.00E+00 7.52E-03 -3.13E-03 6.27E-04 -4.77E-05 1.17E-06

[0139] Figure 9 The field curvature curve graph of Embodiment 2 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 ±0.05 mm, indicating that the optical lens can excellently correct the field curvature.

[0140] Figure 10 The F-Theta distortion curve graph of Embodiment 2 is shown, which represents the F-Theta distortion of light rays with different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-Theta distortion (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Theta distortion of the optical lens is controlled within 0-60% and the edge distortion changes smoothly, indicating that the F-Theta distortion of the optical lens is effectively controlled, which is beneficial for later restoration through software algorithms.

[0141] Figure 11 The relative illumination curve graph of Embodiment 2 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 40% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0142] Figure 12 The modulation transfer function (MTF) curve graph of Embodiment 2 is shown, which represents the modulation degree 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 in the entire field of view. In the range of 0-160 lp / mm, the MTF curve uniformly and smoothly decreases 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.

[0143] 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, indicating that the optical lens can correct the axial aberration well.

[0144] 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 ±3 μm, indicating that the optical lens can correct the chromatic aberration of the marginal field of view and the secondary spectrum of the entire image plane extremely well.

[0145] Example 3

[0146] 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 sequentially includes, along the optical axis from the object side to the imaging plane: 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, and a filter G1 and a protective glass G2.

[0147] The first lens L1 has a negative focal power. Its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface.

[0148] The second lens L2 has a negative focal power. Its object side surface S3 is a convex surface, and its image side surface S4 is a concave surface.

[0149] The third lens L3 has a negative focal power. Its object side surface S5 and image side surface S6 are both concave surfaces.

[0150] Diaphragm ST

[0151] The fourth lens L4 has a positive focal power. Its object side surface S7 and image side surface S8 are both convex surfaces.

[0152] The fifth lens L5 has a positive focal power. Its object side surface S9 and image side surface S10 are both convex surfaces.

[0153] The sixth lens L6 has a negative focal power. Its object side surface S11 and image side surface S12 are both concave surfaces.

[0154] The seventh lens L7 has a positive focal power. Its object side surface S13 and image side surface S14 are both convex surfaces.

[0155] Filter G1, whose object side S15 and image side S16 are both flat;

[0156] Protective glass G2, whose object side S17 and image side S18 are both flat;

[0157] Imaging surface S19 is flat;

[0158] The fifth lens L5 and the sixth lens L6 can be glued together to form a cemented lens.

[0159] The relevant parameters of each lens in the optical lens of Embodiment 3 are shown in Table 3-1.

[0160] Table 3-1

[0161]

[0162]

[0163] The surface shape parameters of the aspherical lenses in the optical lens of Embodiment 3 are shown in Table 3-2.

[0164] Table 3-2

[0165] Plane number K A B C D E F S3 5.01E+01 0.00E+00 3.82E-03 -2.69E-04 9.98E-06 -1.85E-07 1.42E-09 S4 -8.03E-01 0.00E+00 -3.26E-03 2.53E-03 -6.46E-04 6.60E-05 -2.69E-06 S5 -1.36E+01 0.00E+00 -4.91E-03 6.07E-04 -1.60E-04 1.87E-05 -7.41E-07 S6 -1.29E+01 0.00E+00 4.89E-03 2.32E-03 -2.51E-03 1.55E-03 -2.95E-04 S13 1.43E-01 0.00E+00 -3.04E-03 1.74E-04 3.09E-05 -3.84E-06 1.21E-07 S14 -2.18E+00 0.00E+00 1.60E-02 -2.52E-03 2.51E-04 -8.44E-06 -3.06E-08

[0166] Figure 16 The field curvature curve diagram of Embodiment 3 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 ±0.05 mm, indicating that the optical lens can correct the field curvature extremely well.

[0167] Figure 17 The F-Theta distortion curve diagram of Embodiment 3 is shown, which represents the F-Theta distortion of light rays with different wavelengths at different image heights on the imaging surface. The horizontal axis represents the F-Theta distortion (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Theta distortion of the optical lens is controlled within 0-60% and the edge distortion changes smoothly, indicating that the F-Theta distortion of the optical lens is effectively controlled, which is beneficial for later restoration through software algorithms.

[0168] Figure 18 The relative illumination curve diagram of Embodiment 3 is shown, which represents the relative illumination 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 illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 40% at the maximum semi-field angle, indicating that the optical lens has good relative illumination.

[0169] Figure 19 The modulation transfer function (MTF) curve of Example 3 is shown, which represents the modulation of 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 smoothly decreases uniformly from the central field of view to the edge field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency cases.

[0170] Figure 20 The 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 ±15 μm, indicating that the optical lens can correct the axial aberration well.

[0171] 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 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, 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.

[0172] Please refer to Table 4 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 field of view angle FOV of the optical lens, and the values corresponding to each conditional formula in the embodiment.

[0173] Table 4

[0174] Parameters and conditional expressions Example 1 Example 2 Example 3 f (mm) 1.66 1.30 1.42 TTL (mm) 32.69 22.17 24.61 FNO 1.80 2.02 2.00 IH (mm) 6.99 6.80 7.18 EPD (mm) 0.92 0.65 0.71 FOV (°) 196 190 190 θ (rad) 3.42 3.32 3.32 CRA (°) 18.43 19.18 18.22 TTL / IH 4.67 3.26 3.43 IH / f 4.22 5.22 5.06 BFL / f 1.95 1.35 1.49 FOV / f (° / mm) 118.13 145.81 133.98 IH / EPD 7.59 10.54 10.13 <![CDATA[IH h / IH]]> 0.44 0.42 0.40 (IH / 2) / (f×(θ / 2)) 1.23 1.57 1.53 (FOV / 2) / CRA 5.32 4.95 5.21 <![CDATA[f1 / f]]> -9.27 -12.96 -10.12 <![CDATA[f2 / f]]> -3.59 -3.93 -3.44 <![CDATA[f3 / f]]> -12.05 -5.30 -13.89 <![CDATA[f4 / f]]> 5.70 2.73 3.07 <![CDATA[f5 / f]]> 2.49 3.04 3.21 <![CDATA[f6 / f]]> -1.64 -1.70 -1.69 <![CDATA[f7 / f]]> 2.69 2.04 2.81 <![CDATA[f 56 / f]]> -46.11 -6.79 -6.08 <![CDATA[R1 / f]]> 12.37 14.67 13.33 <![CDATA[R2 / f]]> 4.55 5.90 4.74 <![CDATA[(Sag3 / d3) / (Sag4 / d4)]]> 0.39 0.35 0.30 ∑CT / TTL 0.53 0.65 0.60

[0175] In summary, the optical lens of the embodiment of the present invention realizes the advantages of having a large field of view and a large image plane simultaneously by reasonably matching the lens shapes and the combination of optical powers between the lenses.

[0176] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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.

[0177] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for 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 for the present invention shall be subject to the appended claims.

Claims

1. An optical lens, comprising seven lenses in total, characterized in that, From the object side to the imaging plane along the optical axis are successively: A first lens with negative optical power, whose object side is convex and image side is concave; A second lens with negative optical power, whose object side is convex and image side is concave; A third lens with negative optical power, whose object side is concave; A fourth lens with positive optical power, whose object side and image side are both convex; A fifth lens with positive optical power, whose object side and image side are both convex; A sixth lens with negative optical power, whose object side and image side are both concave; A seventh lens with positive optical power, whose object side and image side are both convex; The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 4.2 < IH / f; The entrance pupil diameter EPD of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 7.5 < IH / EPD < 11.

0.

2. The optical lens according to claim 1, characterized in that, The overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 3.0 < TTL / IH < 5.

0.

3. The optical lens according to claim 1, characterized in that, The optical lens satisfies at least one of the following conditional expressions; The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 4.2 < IH / f ≤ 5.22; The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -14.0 < f1 / f < -9.0; The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -15.0 < f3 / f < -5.0; The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.0 < f4 / f < 6.0; The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 2.0 < f5 / f < 3.5; The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.0 < f6 / f < -1.0; The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.0 < f7 / f < 3.

0.

4. The optical lens according to claim 1, characterized in that, The true image height IH corresponding to the maximum field of view angle of the optical lens and the true image height IH corresponding to the maximum half field of view angle h Satisfy: 0.38 < IH h / IH < 0.

45.

5. The optical lens according to claim 1, characterized in that, The effective focal length f, the maximum field of view angle θ, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.2 < (IH / 2) / (f×(θ / 2)) < 1.

6.

6. The optical lens according to claim 1, characterized in that, The maximum field of view angle FOV of the optical lens and the incident angle CRA of the chief ray of the maximum field of view angle on the image plane satisfy: 4.5 < (FOV / 2) / CRA < 5.

5.

7. The optical lens according to claim 1, wherein The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -3.

0.

8. The optical lens according to claim 1, wherein The effective focal length f of the optical lens and the curvature radii R1 of the object side and R2 of the image side of the first lens respectively satisfy: 12.0 < R1 / f, R2 / f < 6.

0.

9. The optical lens according to claim 1, wherein The sag Sag3 and the clear aperture semi-diameter d3 of the object side of the second lens and the sag Sag4 and the clear aperture semi-diameter d4 of the image side of the second lens satisfy: 0.28 < (Sag3 / d3) / (Sag4 / d4) < 0.

40.

10. The optical lens according to claim 1, wherein, The total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis respectively satisfy: 0.50 < ∑CT / TTL < 0.70.

Images