Optical lens

Abstract

The present invention provides an optical lens, which includes, from the object side to the imaging surface along the optical axis: a first lens with negative optical power, whose object side surface is convex and whose image side surface is concave; a second lens with negative optical power, whose object side surface is concave and whose image side surface is convex; a third lens with positive 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; a fourth lens with positive optical power, whose object side surface is convex and whose image side surface is convex; a fifth lens with positive optical power, whose image side surface is convex; a sixth lens with negative optical power, whose object side surface is concave and whose image side surface is convex; a seventh lens with positive optical power, whose object side surface is convex and whose image side surface is concave at the near optical axis. The optical lens provided by the present invention can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens.

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] Body cameras are mainly used to digitally record on-site conditions during law enforcement, such as video, photo, and audio recording, so that effective on-site image data can be provided afterwards. During on-site law enforcement, law enforcement officers need to record a large range of clear images, but the lenses of body cameras on the market either have too small an aperture, resulting in dark images, or have too small a field of view, which prevents them from recording too many images.

[0003] Therefore, how to make the lens of the body camera meet high imaging quality is a problem that needs to be solved urgently. Summary of the invention

[0004] 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.

[0005] The technical solution adopted by the present invention is:

[0006] An optical lens, composed of seven lenses, including the following lenses in order from the object side to the imaging surface along the optical axis:

[0007] 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;

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

[0009] The third lens has positive refractive power, its object side surface is convex at the near optical axis, and its image side surface is concave at the near optical axis;

[0010] a fourth lens having positive refractive power, whose object-side surface is convex and whose image-side surface is convex;

[0011] a fifth lens element having positive refractive power and having a convex image-side surface;

[0012] a sixth lens having negative optical power, whose object side surface is concave and whose image side surface is convex;

[0013] The seventh lens element has positive refractive power, its object side surface is convex, and its image side surface is concave near the optical axis;

[0014] Among them, the object side surface curvature radius R9 of the fifth lens and the image side surface curvature radius R10 of the fifth lens satisfy: 0.5<(R9-R10) / (R9+R10)<1.5; the object side surface curvature radius R13 of the seventh lens and the image side surface curvature radius R14 of the seventh lens satisfy: -0.5<(R13-R14) / (R13+R14)<0.

[0015] More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4.5 < TTL / f < 5.3; the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 2.7 < IH / f < 3.2.

[0016] More preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 9 < f3 / f < 15; the curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: -0.5 < (R5 - R6) / (R5 + R6) < 0.

[0017] More preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.2.

[0018] More preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.9 < f5 / f < 1.4; the curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: |R9 / R10| > 13.

[0019] More preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: f7 / f > 12.

[0020] More preferably, the combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f4567 of the fourth, fifth, sixth, and seventh lenses satisfy: 2.4 < f56 / f4567 < 4.6.

[0021] More preferably, the curvature radius R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: -10.8 < R4 / f < -3.8; the curvature radius R3 of the object side of the second lens and the curvature radius R4 of the image side of the second lens satisfy: -1 < (R3 - R4) / (R3 + R4) < -0.5.

[0022] More preferably, the curvature radius R13 of the object side of the seventh lens and the effective focal length f of the optical lens satisfy: 2.6 < R13 / f < 3.8; the curvature radius R14 of the image side of the seventh lens and the effective focal length f of the optical lens satisfy: 3.5 < R14 / f < 6.5.

[0023] Further preferably, the sagittal height Sag9 of the clear aperture of the object side surface of the fifth lens and the clear aperture diameter d9 of the object side surface of the fifth lens satisfy: 0 < Sag9 / d9 < 0.2; the sagittal height Sag10 of the clear aperture of the image side surface of the fifth lens and the clear aperture diameter d10 of the image side surface of the fifth lens satisfy: -0.85 < Sag10 / d10 < -0.5.

[0024] Compared with the prior art, 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 a large field of view angle, a large aperture, and high imaging quality. Description of the Drawings

[0025] 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:

[0026] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 2 is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 is an F-Theta distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 6 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 7 is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 8 is an F-Theta distortion curve diagram of the optical lens in Embodiment 2 of the present invention.

[0034] Fig. 9 is an axial aberration curve diagram of the optical lens in Embodiment 2 of the present invention.

[0035] Fig.10 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 2 of the present invention.

[0036] Fig.11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0037] Fig.12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0038] Fig.13 Graph showing the F-Theta distortion of the optical lens in Embodiment 3 of the present invention.

[0039] Fig.14 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0040] Fig.15 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0041] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] The optical lens provided by the embodiment of the present invention is composed of seven lenses, 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.

[0050] In some embodiments, the first lens may have a negative optical power, with its object side surface being convex and its image side surface being concave. The second lens may have a negative optical power, with its object side surface being concave and its image side surface being convex. The third lens may have a positive optical power, with its object side surface being convex at the near optical axis and its image side surface being concave at the near optical axis. The fourth lens may have a positive optical power, with its object side surface being convex and its image side surface being convex. The fifth lens may have a positive optical power, with its object side surface being concave or convex and its image side surface being convex. The sixth lens may have a negative optical power, with its object side surface being concave and its image side surface being convex. The seventh lens may have a positive optical power, with its object side surface being convex and its image side surface being concave at the near optical axis.

[0051] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the third lens and the fourth lens. It is understood that the aperture is used to limit the amount of light entering to change the brightness of the image. When the aperture is located between the third lens and the fourth lens, it is convenient to correct the aperture aberration.

[0052] In some embodiments, the optical lens may further include a filter, which 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.

[0053] In some embodiments, the fifth lens and the sixth lens may be cemented together to form a cemented lens with positive optical power, which can effectively correct the chromatic aberration of the optical lens, reduce the decentration sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0054] In some embodiments, the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: 0.5 < (R9 - R10) / (R9 + R10) < 1.5; 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: -0.5 < (R13 - R14) / (R13 + R14) < 0. Meeting the above ranges can control the fifth lens and the seventh lens to have appropriate surface shapes, effectively improve the field curvature and aberration, and improve the imaging quality of the optical lens. More specifically, 0.86 < (R9 - R10) / (R9 + R10) < 1.1; -0.27 < (R13 - R14) / (R13 + R14) < -0.06.

[0055] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4.5 < TTL / f < 5.3. Meeting the above range can effectively limit the length of the lens, which is beneficial to the miniaturization of the optical lens. More specifically, 5 < TTL / f < 5.28.

[0056] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 2.7 < IH / f < 3.2. Meeting the above range can endow the optical lens with the characteristic of a larger image surface and can better achieve the high-definition imaging quality of the lens. More specifically, 2.73 < IH / f < 2.9.

[0057] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 9 < f3 / f < 15; 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: -0.5 < (R5 - R6) / (R5 + R6) < 0. Meeting the above ranges, by reasonably setting the focal length and surface shape of the third lens, the light can be effectively converged, the difficulty of correcting the distortion of the peripheral field of view can be reduced, and the overall imaging quality can be improved. More specifically, 10.16 < f3 / f < 13.98; -0.34 < (R5 - R6) / (R5 + R6) < -0.18.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.2. Meeting the above ranges, the light can be further effectively converged, the aberration generated by the front lens can be corrected, and the overall imaging quality can be improved. More specifically, 1.03 < f4 / f < 1.15.

[0059] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.9 < f5 / f < 1.4; the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: |R9 / R10| > 13. Meeting the above ranges, the fifth lens can have a positive optical power and a suitable surface shape, which is beneficial to improving the light converging ability of the optical lens, and at the same time can balance the aberration of the optical lens and improve the imaging quality of the optical lens. More specifically, 0.98 < f5 / f < 1.28; 14.02 < |R9 / R10| < 22.82.

[0060] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: f7 / f > 12. Meeting the above ranges, the seventh lens can have an appropriate positive optical power, which is beneficial to balancing the field curvature of the optical lens and improving the imaging quality of the optical lens. More specifically, 13.95 < f7 / f < 29.96.

[0061] In some embodiments, the combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f4567 of the fourth, fifth, sixth, and seventh lenses satisfy: 2.4 < f56 / f4567 < 4.6. Meeting the above ranges, the fifth and sixth lenses form a cemented lens with a positive optical power, which can further converge the incident light, reduce the loss of light energy, and at the same time enable the diverging light to converge smoothly and enter the rear, further making the light trend transition smoothly and improving the relative illumination of the peripheral field of view. More specifically, 2.7 < f56 / f4567 < 4.16.

[0062] In some embodiments, 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: -10.8 < R4 / f < -3.8; 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: -1 < (R3 - R4) / (R3 + R4) < -0.5. Meeting the above ranges is conducive to the smooth trend of light rays and reduces the aberration correction pressure of the rear lens of the optical lens. More specifically, -9.91 < R4 / f < -4.22; -0.84 < (R3 - R4) / (R3 + R4) < -0.64.

[0063] In some embodiments, 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: 2.6 < R13 / f < 3.8; 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: 3.5 < R14 / f < 6.5. Meeting the above ranges can make the seventh lens have an appropriate surface shape, which is conducive to balancing the field curvature of the optical lens and improving the imaging quality of the optical lens. More specifically, 2.88 < R13 / f < 3.49; 3.79 < R14 / f < 5.94.

[0064] In some embodiments, the sagittal height Sag9 of the object side surface clear aperture of the fifth lens and the object side surface clear aperture d9 of the fifth lens satisfy: 0 < Sag9 / d9 < 0.2; the sagittal height Sag10 of the image side surface clear aperture of the fifth lens and the image side surface clear aperture d10 of the fifth lens satisfy: -0.85 < Sag10 / d10 < -0.5. Meeting the above ranges helps to control the trend of light rays in the edge field of view and highlight the detailed information of the central field of view of the optical lens. More specifically, 0.01 < Sag9 / d9 < 0.13; -0.77 < Sag10 / d10 < -0.62.

[0065] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the radian θ of the maximum half field of view angle satisfy: 0.9 < (IH / 2) / (f×θ) < 1.1. Meeting the above ranges controls the distortion within a small range and is conducive to increasing the true image height. More specifically, 0.92 < (IH / 2) / (f×θ) < 0.99.

[0066] In some embodiments, the maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 85° < FOV / Fno < 95°. Meeting the above ranges defines that the optical lens has an appropriate field of view angle and aperture value, can collect light rays at large angles, and obtain good imaging quality. More specifically, the maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 86.44° < FOV / Fno < 88.03°.

[0067] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL satisfy: 0.9 < BFL / f < 1.1. Meeting the above range can make the lens have an appropriate back focus, which is beneficial to the assembly of the module, reduces interference, and improves the production yield. More specifically, 0.9 < BFL / f < 0.98.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.6 < f1 / f < -1.2. Meeting the above range, by setting the first lens to have a large negative refractive power, it can ensure that the first lens can receive a larger angle of light and collect as much light as possible into the rear optical system, increasing the light flux while achieving a large field of view, and better realizing the large aperture performance of the lens. More specifically, -1.5 < f1 / f < -1.39.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -2.3 < f2 / f < -1.7. Meeting the above range, by reasonably setting the optical power and surface shape of the second lens, the incident light can be further diverged, which is beneficial to improving the field of view angle of the system, reducing the difficulty of distortion correction of the edge field of view while increasing the field of view angle, making the lens have less distortion, and improving the overall imaging quality. More specifically, -2.08 < f2 / f < -1.89.

[0070] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.2 < f6 / f < -1.5. Meeting the above range, by reasonably controlling the focal length of the sixth lens, it is beneficial to increase the imaging area and field of view angle of the optical lens, and improve the imaging quality of the optical lens. More specifically, -2.02 < f6 / f < -1.71.

[0071] In some embodiments, the effective focal length f of the optical lens and the curvature radius R5 of the object side surface of the third lens satisfy: 2.7 < R5 / f < 3.8; the effective focal length f of the optical lens and the curvature radius R6 of the image side surface of the third lens satisfy: 3.9 < R6 / f < 7.8. Meeting the above range can receive as much light as possible from the edge field of view at the front end of the optical lens; at the same time, it can correct spherical aberration and field curvature, reduce the aberration correction pressure of the rear lens of the optical lens; and it is beneficial to the smooth trend of light, improving the imaging quality of the optical lens. More specifically, 2.98 < R5 / f < 3.54; 4.37 < R6 / f < 7.09.

[0072] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R7 of the object side surface of the fourth lens satisfy: 1.6 < R7 / f < 2.3; the effective focal length f of the optical lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: -1.7 < R8 / f < -1.2. Satisfying the above ranges, controlling the fourth lens to have a suitable surface shape can further converge light, correct the aberration generated by the front lens, and improve the overall imaging quality. More specifically, 1.77 < R7 / f < 2.13; -1.55 < R8 / f < -1.33.

[0073] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R11 of the object side surface of the sixth lens satisfy: -0.8 < R11 / f < -0.4; the effective focal length f of the optical lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -1.7 < R12 / f < -1.2. Satisfying the above ranges, controlling the sixth lens to have a suitable surface shape is beneficial to increasing the imaging area and field of view angle of the optical lens, is beneficial to balancing the aberration of the optical lens, and improving the imaging quality of the optical lens. More specifically, -0.67 < R11 / f < -0.54; -1.58 < R12 / f < -1.38.

[0074] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the overall optical length TTL of the optical lens satisfy: 0.5 < ∑CT / TTL < 0.7. Satisfying the above ranges can effectively compress the overall length of the optical lens, and is beneficial to the structural design and production process of the optical lens. More specifically, 0.57 < ∑CT / TTL < 0.63.

[0075] In some embodiments, the clear aperture radius d1 of the object side surface of the first lens and the clear aperture radius d6 of the image side surface of the third lens satisfy: 2 < d1 / d6 < 2.5; the clear aperture radius d7 of the object side surface of the fourth lens and the clear aperture radius d14 of the image side surface of the seventh lens satisfy: 0.3 < d7 / d14 < 0.55. Satisfying the above ranges, reasonably matching the aperture ratios of each lens is convenient for structural design and helps to improve the imaging quality of the optical lens. More specifically, 2.1 < d1 / d6 < 2.31; 0.4 < d7 / d14 < 0.45.

[0076] In some embodiments, the optical lens satisfies the conditional formula: 3mm < f < 3.6mm, 165° < FOV < 175°, 1.5mm < EPD < 1.9mm, 16.5mm < TTL < 17.5mm, 1.8 < Fno < 2.1, 9mm < IH < 9.6mm, 11° < CRA < 13°, 2.8mm < BFL < 3.5mm, where 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 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 conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of a large field of view angle, a short total length, and a small CRA. More specifically, 3.21mm < f < 3.41mm, 168° < FOV < 170°, 1.64mm < EPD < 1.78mm, 16.9mm < TTL < 17.1mm, 1.9 < Fno < 2, 9.2mm < IH < 9.4mm, 11.9° < CRA < 12.5°, 3mm < BFL < 3.3mm.

[0077] 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. Additionally, 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 first lens and the fourth lens in the optical lens provided by the present invention adopt glass lenses, and the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens adopt plastic lenses. Adopting a glass-plastic hybrid structure can improve the thermal stability performance.

[0078] 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 the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the first lens of the present invention adopts a spherical lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can all adopt aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens.

[0079] 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 equation:

[0080] ;

[0081] 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.

[0082] 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.

[0083] Example 1

[0084] 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.

[0085] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0086] The second lens L2 has negative refractive power, its object-side surface S3 is concave, and its image-side surface S4 is convex;

[0087] The third lens L3 has positive refractive power, an object-side surface S5 thereof is convex at the near optical axis, and an image-side surface S6 thereof is concave at the near optical axis;

[0088] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex, and its image-side surface S8 is convex;

[0089] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex, and its image-side surface is convex;

[0090] The sixth lens L6 has negative refractive power, its object-side surface is concave, and its image-side surface S11 is convex;

[0091] The fifth lens L5 and the sixth lens L6 form a cemented lens group with positive refractive power, that is, the cemented surface between the image side surface of the fifth lens L5 and the object side surface of the sixth lens L6 is S10;

[0092] The seventh lens L7 has positive refractive power, its object-side surface S12 is convex, and its image-side surface S13 is concave at the near optical axis;

[0093] The object side surface S14 and the image side surface S15 of the filter G1 are both planes;

[0094] The imaging surface S16 is a plane.

[0095] The first lens L1 is a glass spherical lens, the fourth lens L4 is a glass aspherical lens, and the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are all plastic aspherical lenses.

[0096] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0097] Table 1-1

[0098]

[0099] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0100] Table 1-2

[0101]

[0102] Figure 2 The field curvature curve of the optical lens 100 in this embodiment is shown, which represents the field curvature of light in the meridional image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.15mm, indicating that the optical lens 100 can correct the field curvature well.

[0103] Figure 3 The F-Theta distortion curve of Example 1 is shown, which represents the distortion of light of different wavelengths at different image heights on the imaging surface, with the horizontal axis representing the distortion value (unit: %) and the vertical axis representing the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within ±5%, indicating that the optical lens 100 can correct the distortion well.

[0104] Figure 4 The axial aberration curve of the optical lens 100 in this embodiment 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. It can be seen from the figure that the offset of the axial aberration is controlled within ±0.03mm, indicating that the optical lens 100 can correct the axial aberration well.

[0105] Figure 5The vertical axis chromatic aberration curve of the optical lens 100 in this embodiment 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 axis 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 axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±10 μm, indicating that the optical lens 100 can correct chromatic aberration well.

[0106] Example 2

[0107] 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 differences of this embodiment are: the object side surface S9 of the fifth lens L5 is concave at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0108] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0109] Table 2-1

[0110]

[0111] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0112] Table 2-2

[0113]

[0114] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 7 , Figure 8 , Fig. 9 , Fig.10 shown.

[0115] from Figure 7 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 200 can correct the field curvature well.

[0116] from Figure 8 It can be seen that the distortion of the optical lens is controlled within ±6%, indicating that the optical lens 200 can correct the distortion well.

[0117] from Fig. 9 It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0118] from Fig.10It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±10 μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0119] Example 3

[0120] 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 S9 of the fifth lens L5 is concave at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0121] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0122] Table 3-1

[0123]

[0124] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0125] Table 3-2

[0126]

[0127] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 300 are respectively as follows: Fig.12 , Fig.13 , Fig.14 , Fig.15 shown.

[0128] from Fig.12 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.15mm, indicating that the optical lens 300 can correct the field curvature well.

[0129] from Fig.13 It can be seen that the distortion of the optical lens is controlled within ±8%, indicating that the optical lens 300 can correct the distortion well.

[0130] from Fig.14 It can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0131] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±10 μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0132] 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 real image height IH corresponding to the maximum field of view angle, the chief ray incident angle CRA at the maximum image height, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0133] Table 4

[0134]

[0135] In summary, the optical lens provided by the present invention has at least the following advantages:

[0136] (1) Through specific surface shape settings and reasonable optical focal length distribution, the lens has an ultra-wide angle, which can obtain more scene information and meet the needs of wide-range shooting.

[0137] (2) It has a large aperture and high relative illumination, which enables high-definition imaging even in dim environments. At the same time, the first lens is convex, which helps to converge the incident light, reduce the diameter of the head lens, and facilitate miniaturization of the head. At the same time, the first lens is made of glass and has a scratch-resistant effect.

[0138] (3) The optical lens of the present invention can reasonably correct the overall aberration of the optical lens, achieve high-definition imaging, and improve the imaging quality of the optical lens.

[0139] (4) The glass-plastic hybrid structure improves the stability of the lens under high and low temperature conditions while improving the imaging quality. At the same time, the lens has a smaller CRA, which can match the chip well and ensure good resolution quality.

[0140] 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.

[0141] 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, consisting of seven lenses, characterized in that: It sequentially 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 negative optical power, whose object side is concave and whose image side is convex; A third lens with positive optical power, whose object side is convex near the optical axis 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 positive optical power, whose image side is convex; A sixth lens with negative optical power, whose object side is concave and whose image side is convex; A seventh lens with positive optical power, whose object side is convex and whose image side is concave near the optical axis; Wherein, the curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: 0.5 < (R9 - R10) / (R9 + R10) < 1.5; the curvature radius R13 of the object side of the seventh lens and the curvature radius R14 of the image side of the seventh lens satisfy: -0.5 < (R13 - R14) / (R13 + R14) < 0; The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 2.7 < IH / f < 3.2; the combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: 2.4 < f56 / f4567 < 4.

6.

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: 4.5 < TTL / f < 5.3; the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 2.73 < IH / f < 2.

9.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 9 < f3 / f < 15; the curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: -0.5 < (R5 - R6) / (R5 + R6) < 0.

4. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.

2.

5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.9 < f5 / f < 1.4; the curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: |R9 / R10| > 13.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: f7 / f > 12.

7. The optical lens according to claim 1, characterized in that: The curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: 0.86 < (R9 - R10) / (R9 + R10) < 1.1; The curvature radius R13 of the object side of the seventh lens and the curvature radius R14 of the image side of the seventh lens satisfy: -0.27 < (R13 - R14) / (R13 + R14) < -0.06; The radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 14.02 < |R9 / R10| < 22.82; The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 13.95 < f7 / f < 29.96; The combined focal length f56 of the fifth lens and the sixth lens and the combined focal length f4567 of the fourth, fifth, sixth, and seventh lenses satisfy: 2.7 < f56 / f4567 < 4.

16.

8. The optical lens according to claim 1, characterized in that: The radius of curvature R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: -10.8 < R4 / f < -3.8; The radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: -1 < (R3 - R4) / (R3 + R4) < -0.

5.

9. The optical lens according to claim 1, characterized in that: The radius of curvature R13 of the object side of the seventh lens and the effective focal length f of the optical lens satisfy: 2.6 < R13 / f < 3.8; The radius of curvature R14 of the image side of the seventh lens and the effective focal length f of the optical lens satisfy: 3.5 < R14 / f < 6.

5.

10. The optical lens according to claim 1, characterized in that: The sagittal height Sag9 of the object side clear aperture of the fifth lens and the clear aperture diameter d9 of the object side of the fifth lens satisfy: 0 < Sag9 / d9 < 0.2; The sagittal height Sag10 of the image side clear aperture of the fifth lens and the clear aperture diameter d10 of the image side of the fifth lens satisfy: -0.85 < Sag10 / d10 < -0.5.

Images