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 convex surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex 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 fifth lens has negative focal power, and the object side surface of the fifth lens is a convex surface; the image side surface is a concave surface; the sixth lens has negative focal power, the object side surface of the sixth lens is a convex surface near the optical axis, and the image side surface of the sixth lens is a concave surface near the optical axis; 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, small distortion, large target surface, 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, the performance of conference video lenses is a key component, and its 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, seriously affecting the visual effect; or the lens pixel is not high enough, resulting in blurred portraits. 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 convex;

[0008] The third lens has a negative optical power, its object side surface is concave, and its image side surface is convex;

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

[0010] The fifth lens element has a negative optical power, and its object side surface is convex; and its image side surface is concave;

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

[0012] The seventh lens element has positive refractive 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] 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: 0.8 <f123 / f4567<2.1。

[0014] More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.4 < TTL / f < 3.6; 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: 1.15 < TTL / IH < 1.3.

[0015] More 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: 2.7 < IH / f < 2.9; 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: 1.85 < 180°×TTL / IH / FOV < 2.1.

[0016] More preferably, 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: 39° < f×FOV / IH < 41°; the maximum field of view angle FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.5 < FOV / (CRA / 2) < 5.7.

[0017] More preferably, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.5 < f1 / f < -1.3; the curvature radius R1 of the object side of the first lens, the curvature radius R2 of the image side of the first lens and the central thickness CT1 of the first lens satisfy: 4.5 < (R1 - R2) / CT1 < 16.5.

[0018] More preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.2 < f2 / f < 1.4; the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 1 < R3 / f < 1.1; the curvature radius R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: -2.2 < R4 / f < -1.7.

[0019] More preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -17.3 < f3 / f < -9.2; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f4 / f < 1.4.

[0020] More preferably, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -3.1 < f5 / f < -1.9; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2 < f6 / f < -1.5.

[0021] More preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.7 < f7 / f < 2.3; the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.5 < R13 / f < 0.8; the radius of curvature R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R14 / f < 1.7.

[0022] More preferably, the sagittal height Sag3 of the clear aperture of the object side surface of the second lens and the clear aperture diameter d3 of the object side surface of the second lens satisfy: 0.2 < Sag3 / d3 < 0.24; the sagittal height Sag4 of the clear aperture of the image side surface of the second lens and the clear aperture diameter d4 of the image side surface of the second lens satisfy: -0.18 < Sag4 / d4 < -0.12.

[0023] The optical lens provided by the present invention uses seven lenses with specific optical powers. Through specific surface shape combinations and reasonable optical power distributions, it can improve the imaging quality of the optical lens, reduce aberrations, improve the imaging quality of the optical lens, and endow the lens with one or more advantages such as large wide-angle, small distortion, large target surface, and high pixel count. Description of the Drawings

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, 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 graph of the optical lens in Embodiment 1 of the present invention.

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

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

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

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

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

[0032] Figure 8Graph 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 convex. The third lens may have a negative optical power, its object side may be concave, and its image side may be convex. 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 convex; its image side may be concave. The sixth 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. The seventh lens may have a positive 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 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: 0.8 < f123 / f4567 < 2.1. By satisfying the above range and reasonably defining the focal length ratio of the lens groups before and after the diaphragm of the optical lens, the aberration generated by the lens groups before and after the diaphragm can be effectively corrected, and the imaging quality of the optical lens can be improved. More specifically: 0.8 < f123 / f4567 < 2.09.

[0053] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.4 < TTL / f < 3.6; 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: 1.15 < TTL / IH < 1.3. By satisfying the above range, it is beneficial to realize the large target surface characteristic of the optical lens and be able to match a 1 / 1.56-inch large-bottom chip. It is also beneficial to achieve the balance between the volume and the large image surface of the optical lens and realize high-pixel imaging of the lens. More specifically: 3.44 < TTL / f < 3.6; 1.19 < TTL / IH < 1.3.

[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: 2.7 < IH / f < 2.9; 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: 1.85 < 180°×TTL / IH / FOV < 2.1. By satisfying the above ranges and reasonably controlling the ratio of the image height to the focal length of the optical lens, the characteristics of a large image plane 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: 2.78 < IH / f < 2.88; 1.89 < 180°×TTL / IH / FOV < 2.06.

[0055] 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: 39° < f×FOV / IH < 41°; the maximum field of view angle FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.5 < FOV / (CRA / 2) < 5.7. By satisfying the above ranges and reasonably restricting the relationship among the focal length, field of view angle, and image height of the optical lens, it is beneficial to achieve the balance between the large field of view angle and large target surface imaging of the optical lens. At the same time, reasonably restricting the ratio of the field of view angle to the chief ray angle of incidence of the optical lens can provide a large field of view angle, improve the photosensitive performance, and achieve the shooting effect of wide angle and high pixels. More specifically: 39.69° < f×FOV / IH < 40.47°; 5.57 < FOV / (CRA / 2) < 5.63.

[0056] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.5 < f1 / f < -1.3; the curvature radius R1 of the object side of the first lens, the curvature radius R2 of the image side of the first lens, and the central thickness CT1 of the first lens satisfy: 4.5 < (R1 - R2) / CT1 < 16.5. By satisfying the above ranges and reasonably defining the proportion of the optical power of the first lens and the relationship between the lens surface shape and the thickness, it is beneficial to slow down the change degree of the refraction angle of the incident light, avoid excessive aberration caused by too strong refraction change, and is also beneficial to lens processing and improve the yield. More specifically: -1.46 < f1 / f < -1.38; 4.53 < (R1 - R2) / CT1 < 16.45.

[0057] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.2 < f2 / f < 1.4; the radius of curvature R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 1 < R3 / f < 1.1; the radius of curvature R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: -2.2 < R4 / f < -1.7. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the second lens and its surface shape, it is beneficial to converge light and improve the imaging clarity. More specifically: 1.28 < f2 / f < 1.39; 1.03 < R3 / f < 1.09; -2.19 < R4 / f < -1.76.

[0058] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -17.3 < f3 / f < -9.2; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f4 / f < 1.4. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the third lens and the fourth lens, it is possible to effectively balance the lens aberration and improve the imaging quality. More specifically: -17.23 < f3 / f < -9.25; 1.27 < f4 / f < 1.37.

[0059] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -3.1 < f5 / f < -1.9; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2 < f6 / f < -1.5. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the fifth lens and the sixth lens, it is possible to effectively balance the lens aberration and is beneficial to increasing the imaging area of the optical lens. More specifically: -3.07 < f5 / f < -1.96; -1.92 < f6 / f < -1.55.

[0060] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.7 < f7 / f < 2.3; the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.5 < R13 / f < 0.8; the radius of curvature R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R14 / f < 1.7. Satisfying 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 target surface imaging and can better match the backend chip. More specifically: 1.72 < f7 / f < 2.27; 0.57 < R13 / f < 0.77; 1.03 < R14 / f < 1.64.

[0061] In some embodiments, the sagittal height Sag3 of the clear aperture of the object side surface of the second lens and the clear aperture diameter d3 of the object side surface of the second lens satisfy: 0.2 < Sag3 / d3 < 0.24; the sagittal height Sag4 of the clear aperture of the image side surface of the second lens and the clear aperture diameter d4 of the image side surface of the second lens satisfy: -0.18 < Sag4 / d4 < -0.12. Satisfying the above ranges helps to control the light path 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: 5.8 < IH / EPD < 6. Satisfying the above range 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: 5.8 < IH / EPD < 5.98.

[0063] In some embodiments, the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the total optical length TTL of the optical lens satisfy: 0.49 < ΣCT / TTL < 0.52. Satisfying the above range, controlling the total optical length of the optical lens and the sum of the central thicknesses of each lens within a reasonable range, can facilitate structural design and processing and further improve the imaging quality.

[0064] In some embodiments, the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 1.7 < ΣCT / f < 1.9. Satisfying the above range can effectively correct the field curvature and distortion of the optical lens and improve the imaging quality of the optical lens. More specifically: 1.72 < ΣCT / f < 1.82.

[0065] In some embodiments, the clear aperture 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) < 0.6. Satisfying the above range is beneficial to meeting the requirements of the optical lens having a large field of view angle and a large image plane. More specifically: 0.53 < d1 / (IH / 2) / tan(FOV / 2) < 0.6.

[0066] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: 2.1 < R1 / f < 5.9; the radius of curvature R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.5 < R2 / f < 0.7. Meeting the above ranges and reasonably setting the surface shape of the first lens is beneficial to obtaining a wider field of view without changing the physical size of the lens. More specifically: 2.16 < R1 / f < 5.88; 0.52 < R2 / f < 0.68.

[0067] In some embodiments, the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface of the second lens satisfy: -0.62 < R3 / R4 < -0.48; the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface of the second lens satisfy: -0.35 < (R3 + R4) / (R3 - R4) < -0.23. Meeting the above ranges and reasonably defining the surface shape of the second lens helps to adjust the light propagation path and lay a foundation for subsequent good imaging.

[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: 0.42 < R13 / R14 < 0.57; 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: -0.41 < (R13 - R14) / (R13 + R14) < -0.27. Meeting the above ranges and reasonably defining the surface shape of the seventh lens helps the light to be accurately focused on the imaging plane, improving the clarity and brightness uniformity of the image.

[0069] In some embodiments, the optical lens satisfies the following conditional expressions: 3.6 mm < f < 3.9 mm; 112° < FOV < 115°; 1.7 mm < EPD < 1.9 mm; 13.1 mm < TTL < 13.3 mm; 2 < Fno < 2.1; 10 mm < IH < 11 mm; 40° < CRA < 41°; 1 mm < BFL < 1.3 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 total 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 chief 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, low distortion, large target surface, and high pixels. More specifically: 3.66 mm < f < 3.81 mm; 112.9° < FOV < 114.1°; 1.75 mm < EPD < 1.84 mm; 13.11 mm < TTL < 13.21 mm; 2.07 < Fno < 2.09; 10.23 mm < IH < 10.93 mm; 40.5° < CRA < 40.62°; 1.08 mm < BFL < 1.27 mm.

[0070] 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.

[0071] 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.

[0072] 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:

[0073]

[0074] 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.

[0075] 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.

[0076] Example 1

[0077] 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.

[0078] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0079] The second lens L2 has positive refractive power, its object-side surface S3 is convex, and its image-side surface S4 is convex;

[0080] The third lens L3 has negative refractive power, its object-side surface S5 is concave, and its image-side surface S6 is convex;

[0081] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex, and its image-side surface S8 is convex;

[0082] The fifth lens L5 has negative refractive power, its object-side surface S9 is convex, and its image-side surface S10 is concave;

[0083] The sixth lens L6 has negative refractive power, an object-side surface S11 thereof is convex at the near optical axis, and an image-side surface S12 thereof is concave at the near optical axis;

[0084] The seventh lens L7 has positive 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;

[0085] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0086] The imaging surface S17 is a plane.

[0087] 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.

[0088] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0089] Table 1-1

[0090]

[0091] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0092] Table 1-2

[0093] Face number K B C D S1 -1.13E+01 -1.30E-03 1.50E-05 6.23E-07 S2 -6.14E-01 -4.01E-03 1.78E-04 -7.98E-05 S3 -4.81E-01 -1.34E-03 -1.71E-04 -3.88E-05 S4 -1.46E+01 1.80E-03 -1.55E-03 -5.74E-06 S5 3.34E+00 -4.40E-03 -2.41E-03 -1.90E-04 S6 3.67E+01 -3.32E-03 -2.74E-03 2.50E-04 S7 1.84E+00 1.81E-02 -5.94E-03 6.78E-04 S8 7.96E-01 2.62E-03 -1.12E-03 -2.72E-04 S9 -2.36E+01 -2.01E-02 -3.70E-03 1.72E-03 S10 -3.25E+00 -9.20E-03 6.31E-03 -5.27E-04 S11 -1.37E+02 -2.03E-02 -2.75E-03 8.53E-04 S12 -2.46E+01 -1.29E-02 -5.74E-04 2.57E-04 S13 -2.26E+01 -4.26E-03 1.41E-04 -8.50E-06 S14 -6.41E+01 -3.83E-03 5.61E-05 5.90E-06 Face number E F G H S1 -5.25E-09 -8.92E-10 7.23E-12 1.65E-13 S2 -6.99E-07 2.29E-07 1.07E-07 -2.39E-08 S3 -1.31E-05 1.85E-06 -4.11E-08 -1.16E-07 S4 1.19E-06 1.09E-06 3.02E-07 -6.49E-08 S5 1.17E-04 1.40E-05 -2.01E-07 -5.17E-07 S6 1.80E-04 6.96E-05 -4.30E-05 6.84E-06 S7 4.92E-04 -5.61E-05 -6.66E-05 2.72E-05 S8 2.84E-04 1.16E-04 -7.61E-05 2.48E-05 S9 -3.34E-04 -4.16E-05 1.01E-04 -2.70E-05 S10 -6.49E-06 4.03E-05 -1.35E-06 -3.98E-06 S11 -1.57E-04 -2.40E-06 1.30E-06 2.75E-07 S12 -3.08E-05 -6.03E-07 5.42E-07 -3.58E-08 S13 6.04E-07 1.50E-08 -1.74E-09 2.19E-11 S14 -1.27E-07 -1.56E-08 -4.31E-10 3.74E-11

[0094] 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.

[0095] 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 ±0.04 mm, indicating that the optical lens 100 can well correct the field curvature.

[0096] 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 -10% to 0%, indicating that the distortion of the optical lens 100 is well corrected.

[0097] Figure 4 The axial aberration curve of Example 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: 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 ±0.01mm, indicating that the optical lens 100 can better correct the axial aberration.

[0098] 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 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.

[0099] Example 2

[0100] 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.

[0101] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0102] Table 2-1

[0103]

[0104]

[0105] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0106] Table 2-2

[0107] Face number K B C D S1 4.29E+00 -9.83E-04 5.29E-07 5.39E-07 S2 -5.81E-01 -5.26E-04 6.81E-05 -6.48E-05 S3 -1.25E+00 -2.16E-03 -6.16E-04 4.33E-05 S4 3.99E+00 1.57E-03 -3.90E-04 1.01E-05 S5 -7.69E+00 2.82E-03 5.98E-05 -1.35E-04 S6 -1.59E+01 6.45E-03 -7.66E-05 4.27E-06 S7 -4.22E+00 5.31E-03 -1.03E-03 -1.17E-04 S8 5.08E+00 -8.48E-03 2.36E-04 2.14E-04 S9 -3.11E+01 -1.51E-03 -3.07E-03 9.34E-05 S10 -7.41E-01 1.78E-03 -6.25E-04 2.18E-04 S11 -1.97E+02 -1.31E-02 -4.42E-03 6.93E-04 S12 -2.23E+01 -8.59E-03 -1.35E-03 2.35E-04 S13 -1.42E+01 -3.06E-03 -1.83E-05 -5.63E-06 S14 -1.98E+01 -3.47E-03 8.31E-05 2.25E-07 Face number E F G H S1 -2.34E-09 -3.67E-10 -5.62E-12 -4.93E-14 S2 7.59E-06 -3.17E-07 1.21E-09 -3.54E-09 S3 -1.69E-05 1.46E-06 6.10E-08 5.61E-09 S4 6.87E-06 1.00E-06 3.23E-08 4.26E-08 S5 1.61E-08 7.46E-06 7.89E-06 -1.68E-06 S6 1.01E-04 1.21E-05 -1.32E-06 2.20E-06 S7 3.07E-05 5.10E-05 -2.33E-06 1.11E-06 S8 -5.31E-05 1.78E-05 -2.83E-06 3.87E-06 S9 -8.48E-05 4.74E-05 3.45E-06 -3.36E-06 S10 -3.11E-07 1.62E-06 -2.29E-06 -2.14E-08 S11 -4.21E-05 -1.74E-06 4.56E-07 -1.79E-07 S12 -1.04E-05 -6.02E-07 7.81E-08 -3.46E-09 S13 5.30E-07 4.80E-09 -2.11E-10 -1.49E-11 S14 -1.66E-07 -2.26E-09 3.90E-11 2.61E-12

[0108] 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.

[0109] from Figure 7 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.06mm to 0.03mm, indicating that the optical lens 200 can correct the field curvature well.

[0110] from Figure 8 It can be seen that the F-Tan (Theta) distortion of the optical lens is controlled within -8% to 1%, indicating that the distortion of the optical lens 200 is well corrected.

[0111] from Fig. 9 It can be seen from the figure that the offset of the axial aberration is controlled within the range of -0.02 mm to 0.03 mm, which indicates that the optical lens 200 can correct the axial aberration well.

[0112] 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 3μm, 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.

[0113] Example 3

[0114] 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 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.

[0115] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0116] Table 3-1

[0117]

[0118] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0119] Table 3-2

[0120]

[0121]

[0122] 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 respectively as follows: Fig.12 , Fig.13 , Fig.14 , Fig.15 shown.

[0123] 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 0.09mm, indicating that the optical lens 300 can correct the field curvature well.

[0124] from Fig.13 It can be seen that the F-Tan (Theta) distortion of the optical lens is controlled within a range of -8% to 0%, indicating that the distortion of the optical lens 300 is well corrected.

[0125] from Fig.14It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0126] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1μm to 2μm, 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.

[0127] 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.

[0128] Table 4

[0129]

[0130]

[0131] 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, small distortion, large target area, and high pixels.

[0132] 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.

[0133] 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 sequentially includes, from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a positive optical power, whose object side is convex and whose image side is convex; A third lens with a negative optical power, whose object side is concave and whose image side is convex; A fourth lens with a positive optical power, whose object side is convex and whose image side is convex; A fifth lens with a negative optical power, whose object side is convex; whose image side is concave; A sixth lens with a negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A seventh lens with a positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; Wherein, 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: 0.8 < f123 / f4567 < 2.

1.

2. The optical lens according to claim 1, characterized in that: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.4 < TTL / f < 3.6; 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: 1.15 < 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: 2.7 < IH / f < 2.9; 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: 1.85 < 180°×TTL / IH / FOV < 2.

1.

4. The optical lens according to claim 1, characterized in that: 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: 39° < f×FOV / IH < 41°; the maximum field of view angle FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 5.5 < FOV / (CRA / 2) < 5.

7.

5. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.5 < f1 / f < -1.3; the object side curvature radius R1 of the first lens, the image side curvature radius R2 of the first lens and the central thickness CT1 of the first lens satisfy: 4.5 < (R1 - R2) / CT1 < 16.

5.

6. 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: 1.2 < f2 / f < 1.4; the object side curvature radius R3 of the second lens and the effective focal length f of the optical lens satisfy: 1 < R3 / f < 1.1; the image side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -2.2 < R4 / f < -1.

7.

7. 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: -17.3 < f3 / f < -9.2; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f4 / f < 1.

4.

8. 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: -3.1 < f5 / f < -1.9; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2 < f6 / f < -1.

5.

9. 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: 1.7 < f7 / f < 2.3; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.5 < R13 / f < 0.8; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R14 / f < 1.

7.

10. The optical lens according to claim 1, characterized in that: The object-side clear aperture sag Sag3 of the second lens and the object-side clear aperture d3 of the second lens satisfy: 0.2 < Sag3 / d3 < 0.24; the image-side clear aperture sag Sag4 of the second lens and the image-side clear aperture d4 of the second lens satisfy: -0.18 < Sag4 / d4 < -0.12.

Images