Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses, 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 negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens near the optical axis is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens near the optical axis is a convex surface; the sixth lens has positive focal power, the object side surface of the sixth lens near the optical axis is a convex surface, and the image side surface of the sixth lens is a convex surface; and the object side surface of the seventh lens is a convex surface near the optical axis, and the image side surface of the seventh lens is a concave surface near the optical axis. The optical lens provided by the invention has one or more advantages of large wide angle, large aperture, small distortion, high pixel and the like.

Description

Technical Field

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

[0002] With more and more cross-regional collaborative work, video conferencing systems have become an indispensable part of modern productivity. In video conferencing, conference video lenses are key components, and their performance is directly related to the quality of the conference. However, most conference lenses on the market currently have obvious shortcomings. Either the field of view is not large enough, so that the imaging surface cannot fully cover the conference room, and some participants are difficult to fit into the camera; or the distortion is too large, which seriously affects the visual effect; or the lens pixels are not high enough, resulting in blurred portraits; or in a conference room environment with insufficient light, the captured image will be relatively dim. These problems make the existing conference lenses insufficient to fully cover the use needs of video conferencing, greatly limiting the video conferencing experience. Summary of the invention

[0003] In view of the above problems, an object of the present invention is to provide an optical lens having the advantage of excellent imaging quality.

[0004] The technical solution adopted by the present invention is:

[0005] An optical lens, comprising seven lenses, which include:

[0006] The first lens has a negative optical power, the object side surface of which is convex, and the image side surface of which is concave;

[0007] The second lens has positive refractive power, its object side surface is convex, and its image side surface is concave;

[0008] The third lens has positive refractive power, its object side surface is convex, and its image side surface is concave near the optical axis;

[0009] a fourth lens having positive refractive power, whose object-side surface is convex and whose image-side surface is convex;

[0010] A fifth lens element with negative optical power, whose object side surface is concave and whose image side surface is convex near the optical axis;

[0011] a sixth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is convex;

[0012] The seventh lens element has a negative optical power, the object side surface of which is convex at the near optical axis, and the image side surface of which is concave at the near optical axis;

[0013] Among them, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 38° < f × FOV / IH < 41°.

[0014] Further preferably, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < TTL / f < 3.8; the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.2 < TTL / IH < 1.3.

[0015] Further preferably, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.8 < IH / f < 3.1; the overall optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 1.9 < 180° × TTL / IH / FOV < 2.

[0016] Further preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 5 < f2 / f < 12; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.9 < R3 / f < 1.2; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: 1.15 < R4 / f < 1.4.

[0017] Further preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.3 < f3 / f < 6.7; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1 < f4 / f < 1.3.

[0018] Further preferably, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -3.2 < f5 / f < -1.7; the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -1.1 < R9 / f < -0.9; the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -4.2 < R10 / f < -2.1.

[0019] Further preferably, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1.7 < f6 / f < 3.4; the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 2.2 < R11 / f < 3.2; the curvature radius R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: -4.15 < R12 / f < -1.45.

[0020] More preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -151 < f7 / f < -3.4; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R13 / f < 2.9; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.85 < R14 / f < 1.25.

[0021] More preferably, the combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: -5.2 < f123 / f4567 < -2.9; the maximum field of view FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.7 < FOV / (CRA / 2) < 5.9.

[0022] More preferably, the sagittal height Sag9 of the object-side clear aperture of the fifth lens and the object-side clear aperture diameter d9 of the fifth lens satisfy: -0.26 < Sag9 / d9 < -0.15; the sagittal height Sag10 of the image-side clear aperture of the fifth lens and the image-side clear aperture diameter d10 of the fifth lens satisfy: 0 < Sag10 / d10 < 0.04.

[0023] The optical lens provided by the present invention uses seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and endow the lens with one or more advantages such as large wide angle, large aperture, small distortion, and high pixel. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, where:

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

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

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

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

[0029] Figure 5Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0030] Figure 6 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0031] Figure 7 4 is a field curvature curve diagram of the optical lens in Example 2 of the present invention.

[0032] Figure 8 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 2 of the present invention.

[0033] Fig. 9 Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

[0034] Fig.10 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0035] Fig.11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0036] Fig.12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0037] Fig.13 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0038] Fig.14 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0039] Fig.15 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0040] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0041] In order to better understand the present application, a more detailed description will be made of various aspects of the present application 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 are not intended to 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.

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

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

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

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

[0046] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0047] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0048] The optical lens provided by the embodiment of the present invention is composed of seven lenses with optical focal length, which include: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in sequence from the object side to the imaging surface along the optical axis.

[0049] In some embodiments, the first lens may have a negative optical power, its object side may be convex, and its image side may be concave. The second lens may have a positive optical power, its object side may be convex, and its image side may be concave. The third lens may have a positive optical power, its object side may be convex, and its image side may be concave near the optical axis. The fourth lens may have a positive optical power, its object side may be convex, and its image side may be convex. The fifth lens may have a negative optical power, its object side may be concave, and its image side may be convex near the optical axis. The sixth lens may have a positive optical power, its object side may be convex near the optical axis, and its image side may be convex. The seventh lens may have a negative optical power, its object side may be convex near the optical axis, and its image side may be concave near the optical axis.

[0050] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the third lens and the fourth lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image. When the diaphragm is located between the third lens and the fourth lens, it is convenient for correcting the diaphragm aberration.

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

[0052] In some embodiments, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 38° < f×FOV / IH < 41°. Meeting the above range, by reasonably restricting the relationship between the focal length, field of view angle, and image height of the optical lens, it is beneficial to achieve the balance of the large field of view angle and large target surface imaging of the optical lens. More specifically: 38.26° < f×FOV / IH < 40.11°.

[0053] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < TTL / f < 3.8; the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.2 < TTL / IH < 1.3. Meeting the above range is beneficial to achieving the large target surface characteristics of the optical lens and can be matched with a 1 / 1.56-inch large bottom chip. It is also beneficial to achieve the balance of the volume and large image surface of the optical lens and realize high-pixel imaging of the lens. More specifically: 3.55 < TTL / f < 3.77; 1.22 < TTL / IH < 1.26.

[0054] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.8 < IH / f < 3.1; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 1.9 < 180°×TTL / IH / FOV < 2. Satisfying the above ranges, by reasonably controlling the ratio of the image height to the focal length of the optical lens, the large image plane characteristic can be achieved, and the imaging quality can be improved. And it is beneficial to balance the relationship among the total length, image height, and field of view angle of the optical lens. More specifically: 2.88 < IH / f < 3.04; 1.9 < 180°×TTL / IH / FOV < 1.95.

[0055] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 5 < f2 / f < 12; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.9 < R3 / f < 1.2; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: 1.15 < R4 / f < 1.4. Satisfying the above ranges, by reasonably limiting the proportion of the optical power of the second lens and its surface shape, it is beneficial to diverge light rays and improve the brightness of the edge field of view. More specifically: 5.07 < f2 / f < 11.94; 0.95 < R3 / f < 1.18; 1.19 < R4 / f < 1.39.

[0056] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.3 < f3 / f < 6.7; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1 < f4 / f < 1.3. Satisfying the above ranges, by reasonably limiting the proportion of the optical power of the third lens and the fourth lens, the lens aberration can be effectively balanced, and the imaging quality can be improved. More specifically: 2.32 < f3 / f < 6.68; 1.05 < f4 / f < 1.22.

[0057] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -3.2 < f5 / f < -1.7; the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -1.1 < R9 / f < -0.9; the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -4.2 < R10 / f < -2.1. Satisfying the above ranges, by reasonably limiting the proportion of the optical power of the fifth lens and its surface shape, it is beneficial to control the field curvature and reduce the difficulty of aberration correction of the optical lens. More specifically: -3.13 < f5 / f < -1.78; -1.04 < R9 / f < -0.91; -4.13 < R10 / f < -2.14.

[0058] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1.7 < f6 / f < 3.4; the object-side curvature radius R11 of the sixth lens and the effective focal length f of the optical lens satisfy: 2.2 < R11 / f < 3.2; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: -4.15 < R12 / f < -1.45. Meeting the above ranges, by reasonably defining the proportion of the optical power of the sixth lens and its surface shape, it is beneficial to correct coma and spherical aberration and improve the imaging quality of the optical lens. More specifically: 1.79 < f6 / f < 3.36; 2.28 < R11 / f < 3.2; -4.11 < R12 / f < -1.49.

[0059] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -151 < f7 / f < -3.4; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R13 / f < 2.9; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.85 < R14 / f < 1.25. Meeting the above ranges, by reasonably defining the proportion of the optical power of the seventh lens and its surface shape, it is beneficial to achieve large-format imaging and better match the backend chip. More specifically: -150.56 < f7 / f < -3.42; 1.04 < R13 / f < 2.83; 0.88 < R14 / f < 1.21.

[0060] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: -5.2 < f123 / f4567 < -2.9; the maximum field of view FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.7 < FOV / (CRA / 2) < 5.9. Meeting the above ranges, by reasonably defining the ratio of the focal lengths of the lens groups before and after the aperture of the optical lens, the aberration generated by the lens groups before and after the aperture can be effectively corrected, and the imaging quality of the optical lens can be improved. At the same time, reasonably restricting the ratio of the field of view of the optical lens to the chief ray angle of incidence can provide a large field of view, improve the photosensitive performance, and achieve a wide-angle and high-pixel shooting effect. More specifically: -5.18 < f123 / f4567 < -2.92; 5.72 < FOV / (CRA / 2) < 5.85.

[0061] In some embodiments, the sagittal height Sag9 of the clear aperture semi-diameter of the object side surface of the fifth lens and the clear aperture semi-diameter d9 of the object side surface of the fifth lens satisfy: -0.26 < Sag9 / d9 < -0.15; the sagittal height Sag10 of the clear aperture semi-diameter of the image side surface of the fifth lens and the clear aperture semi-diameter d10 of the image side surface of the fifth lens satisfy: 0 < Sag10 / d10 < 0.04. Meeting the above ranges helps to control the light trend and highlight the detailed information of the central field of view of the optical lens.

[0062] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 5.3 < IH / EPD < 5.7. Meeting the above ranges is beneficial to ensuring a large light transmission amount and can reasonably distribute light on the imaging surface. In a scene with complex light conditions, it can also enable the imaging sensor to receive sufficient and uniform light, thereby presenting a properly bright image. More specifically: 5.37 < IH / EPD < 5.65.

[0063] In some embodiments, the clear aperture semi-diameter d1 of the object side surface of the first lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 0.5 < d1 / (IH / 2) / tan(FOV / 2) < 0.7. Meeting the above ranges is beneficial to meeting the requirements of the optical lens having a large field of view angle and a large image surface. More specifically: 0.53 < d1 / (IH / 2) / tan(FOV / 2) < 0.7.

[0064] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.45 < f1 / f < -1.25. Meeting the above ranges can enable the first lens to have an appropriate negative optical power, can slow down the deflection degree of incident light, helps light enter the optical system in a larger range, and is beneficial to expanding the field of view angle of the lens. More specifically: -1.41 < f1 / f < -1.26.

[0065] In some embodiments, the curvature radius R10 of the image side surface of the fifth lens and the curvature radius R11 of the object side surface of the sixth lens satisfy: -1.8 < R10 / R11 < -0.8. Meeting the above ranges enables light to enter the sixth lens at an appropriate angle, ensures a proper light propagation path in the optical system, and is beneficial to improving the imaging clarity. More specifically: -1.8 < R10 / R11 < -0.81.

[0066] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -1.8 < R11 / R12 < -0.7. Meeting the above range can effectively converge light, further optimize the optical path in the optical system, and improve the imaging quality. More specifically: -1.76 < R11 / R12 < -0.75.

[0067] In some embodiments, the radius of curvature R12 of the image side surface of the sixth lens and the radius of curvature R13 of the object side surface of the seventh lens satisfy: -3.95 < R12 / R13 < -0.5. Meeting the above range helps to reduce the aberration of the optical lens, and at the same time is beneficial to increasing the field of view angle and the imaging area. More specifically: -3.92 < R12 / R13 < -0.52.

[0068] In some embodiments, the radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: 1.1 < R13 / R14 < 2.4. Meeting the above range is beneficial to achieving large target surface imaging and matching with the rear-end chip. More specifically: 1.17 < R13 / R14 < 2.35.

[0069] 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: -0.7 < (R5 - R6) / (R5 + R6) < 0. Meeting the above range is beneficial to the correction of the aberration of the optical lens. More specifically: -0.64 < (R5 - R6) / (R5 + R6) < -0.05.

[0070] In some embodiments, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: -2.8 < (R7 - R8) / (R7 + R8) < -1.8. Meeting the above range is beneficial to the correction of the aberration of the optical lens. More specifically: -2.73 < (R7 - R8) / (R7 + R8) < -1.81.

[0071] In some embodiments, the optical lens satisfies the following conditional expressions: 3.5 mm < f < 3.8 mm; 115° < FOV < 117°; 1.8 mm < EPD < 2.1 mm; 13 mm < TTL < 14 mm; 1.8 < Fno < 1.9; 10 mm < IH < 11 mm; 39° < CRA < 41°; 1.2 mm < BFL < 1.5 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, CRA represents the principal ray incident angle at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as wide-angle, large aperture, small distortion, and high pixels. More specifically: 3.5 mm < f < 3.73 mm; 115.9° < FOV < 116.1°; 1.88 mm < EPD < 2.01 mm; 13.21 mm < TTL < 13.24 mm; 1.85 < Fno < 1.87; 10.58 mm < IH < 10.77 mm; 39.72° < CRA < 40.53°; 1.22 mm < BFL < 1.46 mm.

[0072] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt an all-plastic lens structure, which can make the structure of the lens relatively compact, significantly reduce the overall weight of the lens, and reduce the manufacturing cost.

[0073] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses, and can also maintain good imaging quality within a larger field of view range, thereby expanding the shooting range. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention all adopt aspherical lenses.

[0074] In various embodiments of the present invention, when the lens adopts an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0075]

[0076] Among them, z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, K is the quadratic surface coefficient, B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0077] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0078] Example 1

[0079] See also Figure 1 , shown is a schematic diagram of the structure of the optical lens 100 provided in Example 1 of the present invention, and the optical lens 100 includes, from the object side to the imaging surface along the optical axis, a first lens L1, a second lens L2, a third lens L3, an aperture ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and a filter G1.

[0080] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0081] The second lens L2 has positive refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave;

[0082] The third lens L3 has positive refractive power, its object side surface S5 is convex, and its image side surface S6 is concave near the optical axis;

[0083] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex, and its image-side surface S8 is convex;

[0084] The fifth lens L5 has negative refractive power, its object side surface S9 is concave, and its image side surface S10 is convex at the near optical axis;

[0085] The sixth lens L6 has positive refractive power, an object-side surface S11 thereof is convex, and an image-side surface S12 thereof is convex;

[0086] The seventh lens L7 has negative refractive power, an object-side surface S13 thereof is convex at the near optical axis, and an image-side surface S14 thereof is concave at the near optical axis;

[0087] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0088] The imaging surface S17 is a plane.

[0089] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all plastic aspherical lenses.

[0090] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0091] Table 1-1

[0092]

[0093]

[0094] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0095] Table 1-2

[0096] Face number K B C D S1 -3.66E+00 -4.00E-05 -6.39E-06 -3.13E-07 S2 -1.38E+00 8.54E-03 1.51E-04 -1.00E-05 S3 -2.99E-01 -2.24E-03 6.35E-04 -2.13E-05 S4 1.22E+00 -7.67E-04 2.78E-03 -7.13E-05 S5 -1.34E+00 -7.12E-04 2.49E-03 -3.04E-04 S6 1.24E+01 -1.86E-02 3.56E-03 -4.44E-04 S7 -1.35E+00 -3.56E-03 3.31E-03 -1.28E-04 S8 -4.48E+00 -5.69E-04 -1.22E-03 4.57E-04 S9 2.45E+00 1.44E-02 -2.82E-03 1.67E-03 S10 5.26E+01 -7.23E-04 2.84E-03 5.69E-04 S11 -9.56E+01 -6.98E-03 -6.21E-04 1.62E-05 S12 1.61E+01 -3.75E-03 1.37E-03 -3.13E-04 S13 9.86E-02 -2.32E-02 1.49E-03 -1.21E-04 S14 -4.93E+00 -7.98E-03 3.94E-04 -1.44E-05 Face number E F G H S1 1.35E-09 7.23E-11 2.73E-12 -1.83E-13 S2 7.14E-07 -5.87E-08 -1.63E-08 -4.70E-09 S3 9.99E-07 -2.26E-07 -2.93E-08 -2.49E-09 S4 9.37E-06 1.06E-06 -2.37E-07 -2.29E-07 S5 1.55E-06 -2.47E-06 -2.96E-07 -5.62E-08 S6 -2.28E-05 5.91E-06 7.79E-07 -1.25E-07 S7 -1.03E-04 1.62E-05 5.14E-06 2.77E-06 S8 8.13E-06 -1.49E-05 2.90E-06 6.83E-06 S9 2.18E-05 -1.25E-06 -3.39E-06 8.69E-06 S10 9.00E-07 -1.90E-06 -1.80E-07 6.28E-08 S11 1.43E-05 5.20E-06 7.45E-07 -7.24E-08 S12 9.62E-06 4.01E-06 3.04E-07 -4.36E-08 S13 2.22E-06 1.14E-08 -1.05E-08 1.77E-09 S14 5.96E-08 6.07E-09 2.45E-10 -2.06E-11

[0097] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0098] Figure 2 The field curvature curve of Example 1 is shown, which indicates the degree of curvature of light of different wavelengths on the meridional image plane and the sagittal image plane, with the horizontal axis indicating the offset (unit: mm) and the vertical axis indicating the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.08 mm, indicating that the optical lens 100 can well correct the field curvature.

[0099] Figure 3 The F-Tan (Theta) distortion curve of Example 1 is shown, which represents the F-Tan (Theta) distortion at different image heights on the imaging plane, the horizontal axis represents the F-Tan (Theta) distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 100 is controlled within -9% to 0%, indicating that the distortion of the optical lens 100 is well corrected.

[0100] Figure 4The axial aberration curve of Example 1 is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within -0.03mm to 0.04mm, indicating that the optical lens 100 can correct the axial aberration well.

[0101] Figure 5 The vertical chromatic aberration curve of Example 1 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface, 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 -1 μm to 2.5 μm, indicating that the optical lens 100 can perfectly correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image surface.

[0102] Example 2

[0103] See also Figure 6 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0104] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0105] Table 2-1

[0106]

[0107]

[0108] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0109] Table 2-2

[0110] Face number K B C D S1 6.06E+00 2.36E-05 1.21E-05 -1.81E-07 S2 -1.54E+00 6.99E-03 -4.22E-04 -8.17E-06 S3 -9.28E-01 -6.42E-03 -8.86E-05 4.95E-06 S4 -8.20E-01 -1.02E-02 3.18E-03 -1.59E-04 S5 -5.77E+00 8.74E-03 1.92E-03 -1.99E-04 S6 2.29E+00 -6.84E-03 1.61E-03 -3.00E-04 S7 -5.15E-01 2.89E-03 4.93E-04 -1.29E-04 S8 4.21E-01 -2.56E-03 -9.25E-04 -4.09E-06 S9 1.82E+00 3.30E-02 -3.81E-03 5.42E-04 S10 -4.97E+00 1.88E-02 1.38E-03 2.40E-04 S11 -1.10E+02 -4.68E-03 -2.44E-04 1.85E-04 S12 3.40E-02 -4.27E-03 -1.78E-04 2.98E-05 S13 8.43E+00 -2.34E-02 -5.06E-05 3.50E-05 S14 -9.28E+00 -6.89E-03 1.53E-04 -3.51E-06 Face number E F G H S1 -4.10E-11 -1.07E-12 -3.63E-15 6.24E-16 S2 -1.47E-10 4.70E-11 6.79E-12 8.25E-13 S3 4.75E-10 -4.57E-11 -1.12E-11 -2.09E-12 S4 -4.08E-09 -9.10E-10 -5.93E-10 -1.41E-10 S5 -1.24E-07 -2.15E-08 -3.18E-09 -4.54E-10 S6 1.84E-07 1.60E-08 -6.22E-09 -4.33E-09 S7 -1.31E-07 -5.84E-08 -1.92E-08 -1.94E-09 S8 4.82E-08 -2.91E-08 -5.07E-08 -3.94E-08 S9 -9.78E-08 -4.43E-08 -2.55E-08 -1.23E-08 S10 -9.59E-08 2.20E-08 2.35E-08 1.18E-08 S11 9.48E-07 1.99E-07 2.57E-08 -3.04E-09 S12 -7.78E-08 3.36E-08 1.94E-08 6.23E-09 S13 -4.21E-08 -3.20E-09 -1.02E-10 1.85E-11 S14 -7.61E-10 -1.35E-11 4.82E-13 6.43E-14

[0111] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 200 are shown as follows: Figure 7 , Figure 8 , Fig. 9 , Fig.10 shown.

[0112] from Figure 7 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.10mm to 0.12mm, indicating that the optical lens 200 can correct the field curvature well.

[0113] from Figure 8 It can be seen that the F-Tan (Theta) distortion of the optical lens is controlled within -6% to 4%, indicating that the distortion of the optical lens 200 is well corrected.

[0114] from Fig. 9 It can be seen that the offset of the axial aberration is controlled within -0.05mm to 0.06mm, indicating that the optical lens 200 can correct the axial aberration well.

[0115] from Fig.10 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1μm to 2.5μm, indicating that the optical lens 200 can better correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0116] Example 3

[0117] See also Fig.11 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object side surface of the sixth lens is convex at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0118] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0119] Table 3-1

[0120]

[0121]

[0122] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0123] Table 3-2

[0124] Face number K B C D S1 -5.37E+00 -5.29E-05 -6.59E-06 -3.17E-07 S2 -1.39E+00 8.51E-03 1.45E-04 -1.15E-05 S3 -2.84E-01 -2.18E-03 6.38E-04 -2.15E-05 S4 1.18E+00 -9.54E-04 2.75E-03 -7.42E-05 S5 -1.33E+00 -6.91E-04 2.49E-03 -3.06E-04 S6 1.34E+01 -1.85E-02 3.57E-03 -4.44E-04 S7 -1.39E+00 -3.72E-03 3.33E-03 -1.19E-04 S8 -5.00E+00 -5.10E-04 -1.25E-03 4.43E-04 S9 2.44E+00 1.36E-02 -2.71E-03 1.70E-03 S10 5.22E+01 1.30E-04 2.87E-03 5.75E-04 S11 -1.12E+02 -9.10E-03 -7.03E-04 4.96E-05 S12 1.66E+01 -4.59E-03 1.54E-03 -3.10E-04 S13 6.43E-02 -2.35E-02 1.46E-03 -1.24E-04 S14 -4.34E+00 -7.95E-03 3.89E-04 -1.46E-05 Face number E F G H S1 1.08E-09 5.76E-11 2.10E-12 -2.04E-13 S2 5.65E-07 -6.77E-08 -1.61E-08 -4.50E-09 S3 8.64E-07 -2.60E-07 -3.60E-08 -3.63E-09 S4 9.27E-06 1.10E-06 -2.14E-07 -2.21E-07 S5 1.12E-06 -2.56E-06 -3.17E-07 -6.12E-08 S6 -2.30E-05 5.81E-06 7.52E-07 -1.32E-07 S7 -1.00E-04 1.65E-05 5.11E-06 2.71E-06 S8 4.39E-06 -1.40E-05 4.36E-06 7.90E-06 S9 2.13E-05 -2.79E-06 -3.70E-06 8.85E-06 S10 3.77E-06 -9.57E-07 1.91E-08 8.13E-08 S11 2.44E-05 6.89E-06 8.44E-07 -1.33E-07 S12 7.11E-06 3.47E-06 2.24E-07 -5.26E-08 S13 1.98E-06 2.96E-09 -1.05E-08 1.79E-09 S14 5.07E-08 6.01E-09 2.59E-10 -1.93E-11

[0125] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown as follows: Fig.12 , Fig.13 , Fig.14 , Fig.15 shown.

[0126] from Fig.12 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.1mm to 0.3mm, indicating that the optical lens 300 is capable of correcting the field curvature.

[0127] from Fig.13 It can be seen that the F-Tan (Theta) distortion of the optical lens is controlled within a range of -10% to 0%, indicating that the distortion of the optical lens 300 is well corrected.

[0128] from Fig.14 It can be seen that the offset of the axial aberration is controlled within -0.04 mm to 0.06 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0129] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1.5μm to 2.5μm, indicating that the optical lens 300 can extremely well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0130] Please refer to Table 4, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the main ray incidence angle CRA at the maximum image height, the real image height IH corresponding to the maximum field of view angle, the maximum field of view angle FOV, the entrance pupil diameter EPD, the back focal length BFL and the numerical value corresponding to each conditional expression in each embodiment.

[0131] Table 4

[0132]

[0133]

[0134] In summary of the above embodiments, the optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it is possible to improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as wide angle, large aperture, small distortion, and high pixel.

[0135] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0136] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which 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 attached claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: It successively includes from the object side to the imaging surface along the optical axis: A first lens with negative optical power, whose object side is convex and whose image side is concave; A second lens with positive optical power, whose object side is convex and whose image side is concave; A third lens with positive optical power, whose object side is convex and whose image side is concave near the optical axis; A fourth lens with positive optical power, whose object side is convex and whose image side is convex; A fifth lens with negative optical power, whose object side is concave and whose image side is convex near the optical axis; A sixth lens with positive optical power, whose object side is convex near the optical axis and whose image side is convex; A seventh lens with negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; Wherein, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 38° < f×FOV / IH < 41°.

2. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < TTL / f < 3.8; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.2 < TTL / IH < 1.

3.

3. 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 effective focal length f of the optical lens satisfy: 2.8 < IH / f < 3.1; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 1.9 < 180°×TTL / IH / FOV < 2.

4. The optical lens according to claim 1, characterized in that: The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 5 < f2 / f < 12; the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.9 < R3 / f < 1.2; the curvature radius R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: 1.15 < R4 / f < 1.

4.

5. The optical lens according to claim 1, characterized in that: The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.3 < f3 / f < 6.7; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1 < f4 / f < 1.

3.

6. The optical lens according to claim 1, characterized in that: The focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -3.2 < f5 / f < -1.7; the curvature radius R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: -1.1 < R9 / f < -0.9; the curvature radius R10 of the image side of the fifth lens and the effective focal length f of the optical lens satisfy: -4.2 < R10 / f < -2.

1.

7. The optical lens according to claim 1, characterized in that: The focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1.7 < f6 / f < 3.4; the object-side curvature radius R11 of the sixth lens and the effective focal length f of the optical lens satisfy: 2.2 < R11 / f < 3.2; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: -4.15 < R12 / f < -1.

45.

8. The optical lens according to claim 1, characterized in that: The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -151 < f7 / f < -3.4; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R13 / f < 2.9; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.85 < R14 / f < 1.

25.

9. The optical lens according to claim 1, characterized in that: The combined focal length f123 of the first, second, and third lenses and the combined focal length f4567 of the fourth, fifth, sixth, and seventh lenses satisfy: -5.2 < f123 / f4567 < -2.9; the maximum field of view FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.7 < FOV / (CRA / 2) < 5.

9.

10. The optical lens according to claim 1, characterized in that: The object-side clear aperture sag Sag9 of the fifth lens and the object-side clear aperture d9 of the fifth lens satisfy: -0.26 < Sag9 / d9 < -0.15; the image-side clear aperture sag Sag10 of the fifth lens and the image-side clear aperture d10 of the fifth lens satisfy: 0 < Sag10 / d10 < 0.04.

Images