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 positive 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 convex and whose image side surface is concave; a third lens with positive optical power, whose object side surface is convex and whose image side surface is concave; a fourth lens with positive optical power, whose object side surface is concave and whose image side surface is convex; a fifth lens with positive optical power, whose object side surface is convex at the near optical axis; whose image side surface is concave at the near optical axis; a sixth lens with negative optical power; and a seventh lens with negative optical power, whose object side surface is concave 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 through specific surface shape matching and reasonable optical power distribution.

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 the popularity of smart phones, the mobile phone industry is booming, and the public's various demands for mobile phones are also constantly increasing. The camera function of mobile phones has become an important factor in people's choice of mobile phones. Therefore, mobile phone manufacturers have put forward more new requirements for the lens group installed on mobile phones. At the same time, with the improvement of image sensor performance and the reduction of size, the design freedom of the corresponding lens is getting smaller and smaller, and the design difficulty is increasing day by day. Therefore, how to make the mobile phone meet the requirements of high imaging quality while ensuring that the system has high pixels, large target surface and other characteristics, and make the optical system meet the requirements of miniaturization is a problem that needs to be solved urgently. 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, composed of seven lenses, including the following lenses in order from the object side to the imaging surface along the optical axis:

[0006] The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave;

[0007] The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave;

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

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

[0010] The fifth lens element has positive refractive power, and its object side surface is convex at the near optical axis; and its image side surface is concave at the near optical axis;

[0011] a sixth lens having negative optical power;

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

[0013] 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: -0.7<(R9-R10) / (R9+R10)<0; the object side surface curvature radius R7 of the fourth lens and the image side surface curvature radius R8 of the fourth lens satisfy: 3.5<(R7+R8) / (R7-R8)<5.5.

[0014] More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1 < TTL / f < 1.3; the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 34° < FOV / Fno < 42°; the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.85 < IH / EPD < 2.25.

[0015] More preferably, the true image height IH corresponding to the maximum field of view of the optical lens and the back focal length BFL of the optical lens satisfy: 7.6 < IH / BFL < 11.6; the clear aperture radius d7 of the object side of the fourth lens and the clear aperture radius d1 of the object side of the first lens satisfy: 0.6 < d7 / d1 < 0.75.

[0016] More preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.1 < f3 / f < 3.3; 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: -7.5 < (R5 + R6) / (R5 - R6) < -4.2.

[0017] More preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 7.3 < f5 / f < 12.6; the curvature radius R9 of the object side of the fifth lens, the center thickness CT5 of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: 0.5 < (R9 - CT5) / R10 < 1.

[0018] More preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -28.7 < f6 / f < -7.1; the curvature radius R12 of the image side of the sixth lens and the curvature radius R13 of the object side of the seventh lens satisfy: 0.6 < (R12 - R13) / (R12 + R13) < 1.6.

[0019] More preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -1.1 < f7 / f < -0.8; the effective focal length f of the optical lens and the curvature radius R13 of the object side of the seventh lens satisfy: -1.5 < R13 / f < -0.5; the effective focal length f of the optical lens and the curvature radius R14 of the image side of the seventh lens satisfy: 1 < R14 / f < 6.9.

[0020] More preferably, the combined focal length f45 of the fourth lens and the fifth lens and the combined focal length f67 of the sixth lens and the seventh lens satisfy: -4.5 < f45 / f67 < -3.2; the combined focal length f456 of the fourth lens, the fifth lens and the sixth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: -6.6 < f456 / f567 < -3.1.

[0021] More preferably, the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R9 / f < 1.75; the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R10 / f < 2.4.

[0022] More preferably, the sagittal height Sag9 of the object side clear aperture of the fifth lens and the object side clear aperture diameter d9 of the fifth lens satisfy: -0.4 < Sag9 / d9 < -0.1; the sagittal height Sag10 of the image side clear aperture of the fifth lens and the image side clear aperture diameter d10 of the fifth lens satisfy: -0.45 < Sag10 / d10 < 0.

[0023] Compared with the prior art, the optical lens provided by the present invention can effectively shorten the overall length of the optical lens through specific surface shape settings and reasonable optical power distribution, which is beneficial to better realizing the miniaturization and portability of the device; it can also achieve the large target surface characteristics of the lens, and can be matched with a 1-inch ultra-large bottom COMS chip, which is beneficial to improving the lens resolution and the detail restoration degree of the image. In addition, the optical lens of the present invention has a large aperture and can achieve high-definition imaging even in a dim environment; it also has a large field of view angle, so that more scene information can be obtained to meet the needs of large-range shooting. At the same time, it can also reasonably correct the overall aberration of the optical lens, make the optical lens have high pixels, and improve the imaging quality of the optical lens. Description of the Drawings

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

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

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

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

[0028] Figure 4 Graph showing the axial aberration of the optical lens in Example 1 of the present invention.

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

[0030] Figure 6 This is the MTF curve diagram of the optical lens in Example 1 of the present invention.

[0031] Figure 7 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0032] Figure 8 Graph showing the field curvature of the optical lens in Embodiment 2 of the present invention.

[0033] Fig. 9 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 2 of the present invention.

[0034] Fig.10 Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

[0035] Fig.11 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0036] Fig.12 This is an MTF curve diagram of the optical lens in Example 2 of the present invention.

[0037] Fig.13 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0038] Fig.14 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0039] Fig.15 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0040] Fig.16 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0041] Fig.17 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0042] Fig.18 This is the MTF curve diagram of the optical lens in Example 3 of the present invention.

[0043] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] The optical lens provided by the embodiment of the present invention is composed of seven lenses, which are a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in order from the object side to the imaging surface along the optical axis.

[0052] In some embodiments, the first lens may have positive optical power, its object side surface is convex, and its image side surface is concave. The second lens may have negative optical power, its object side surface is convex, and its image side surface is concave. The third lens may have positive optical power, its object side surface is convex, and its image side surface is concave. The fourth lens may have positive optical power, its object side surface is concave, and its image side surface is convex. The fifth lens may have positive optical power, its object side surface is convex at the near optical axis; its image side surface is concave at the near optical axis. The sixth lens may have negative optical power, its object side surface may be concave or convex, and its image side surface may be concave or convex. The seventh lens may have negative optical power, its object side surface is concave, and its image side surface is concave at the near optical axis.

[0053] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the object side and the first lens. It is understood that the aperture is used to limit the amount of incoming light to change the brightness of the image.

[0054] 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 interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0055] In some embodiments, 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: -0.7<(R9-R10) / (R9+R10)<0. Meeting the above range is conducive to smooth transition of light, better correction of aberrations and distortions caused by the front lens, and improvement of overall imaging quality. More specifically, -0.17<(R9-R10) / (R9+R10)<-0.03.

[0056] In some embodiments, the object side curvature radius R7 of the fourth lens and the image side curvature radius R8 of the fourth lens satisfy: 3.5<(R7+R8) / (R7-R8)<5.5. Meeting the above range is conducive to balancing various aberrations of the lens, improving the imaging quality of the optical lens, and reducing the processing difficulty of the fourth lens and improving the processability. More specifically, 3.86<(R7+R8) / (R7-R8)<5.05.

[0057] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1 < TTL / f < 1.3. Satisfying the above range can effectively limit the length of the lens and is conducive to miniaturizing the optical lens. More specifically, 1.12 < TTL / f < 1.14.

[0058] In some embodiments, the maximum field of view FOV of the optical lens and the f-number Fno of the optical lens satisfy: 34° < FOV / Fno < 42°. Satisfying the above range defines that the optical lens has an appropriate field of view and f-number, can collect light at large angles, and obtain good imaging quality. More specifically, 38.1° < FOV / Fno < 38.2°.

[0059] In some embodiments, the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.85 < IH / EPD < 2.25. Satisfying the above range can increase the width of the light beam incident on the optical lens, improve the brightness of the optical lens at the image plane, and avoid vignetting. More specifically, 2 < IH / EPD < 2.1.

[0060] In some embodiments, the true image height IH corresponding to the maximum field of view of the optical lens and the back focal length BFL of the optical lens satisfy: 7.6 < IH / BFL < 11.6. Satisfying the above range enables the optical lens to have a large target surface characteristic and can match a large-size chip. More specifically, 8.41 < IH / BFL < 10.6.

[0061] In some embodiments, the clear aperture radius d7 of the object side of the fourth lens and the clear aperture radius d1 of the object side of the first lens satisfy: 0.6 < d7 / d1 < 0.75. Satisfying the above range, by controlling the aperture ratio of the front and rear lenses, the light path is restricted within a reasonable range, enabling the optical lens to have a short total length, reducing the volume of the optical lens, and maintaining the miniaturization of the optical lens. More specifically, 0.64 < d7 / d1 < 0.69.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.1 < f3 / f < 3.3; the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -7.5 < (R5 + R6) / (R5 - R6) < -4.2. Satisfying the above range is conducive to further convergence of light, enabling the diverging light to smoothly enter the subsequent optical system, better realizing high-quality imaging of the lens; at the same time, it can effectively correct the distortion of the edge field of view, reduce the deformation degree of the edge of the captured image, and improve the image quality. More specifically, 2.36 < f3 / f < 3; -6.87 < (R5 + R6) / (R5 - R6) < -4.69.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 7.3 < f5 / f < 12.6. Meeting the above range can control the contribution of spherical aberration of the fifth lens within a reasonable range, enabling the lens to have a high on-axis imaging resolution ability and facilitating high-definition imaging of the lens. More specifically, 8.16 < f5 / f < 11.5.

[0064] In some embodiments, the curvature radius R9 of the object side surface of the fifth lens, the central thickness CT5 of the fifth lens, and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.5 < (R9 - CT5) / R10 < 1. Meeting the above range can effectively reduce the optical path difference between the center and the periphery of the lens, which is beneficial to correcting the distortion of the optical lens. More specifically, 0.67 < (R9 - CT5) / R10 < 0.84.

[0065] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -28.7 < f6 / f < -7.1. Meeting the above range can effectively balance various aberrations generated by the front lens group, and at the same time is beneficial to increasing the divergence degree of light. More specifically, -26.12 < f6 / f < -7.84.

[0066] In some embodiments, the curvature radius R12 of the image side surface of the sixth lens and the curvature radius R13 of the object side surface of the seventh lens satisfy: 0.6 < (R12 - R13) / (R12 + R13) < 1.6. Meeting the above range can reduce the light deflection angle, make the light trend more stable; at the same time, it can correct coma and field curvature, improve the flatness of imaging, and enhance the imaging quality of the optical lens. More specifically, 0.73 < (R12 - R13) / (R12 + R13) < 1.4.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -1.1 < f7 / f < -0.8; the effective focal length f of the optical lens and the curvature radius R13 of the object side surface of the seventh lens satisfy: -1.5 < R13 / f < -0.5; the effective focal length f of the optical lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: 1 < R14 / f < 6.9. Meeting the above range can effectively balance various aberrations generated by the front lens group, and at the same time is beneficial to increasing the divergence degree of light, increasing the area of light entering the imaging surface, realizing large target surface imaging of the lens, and enhancing the imaging quality of the optical lens. More specifically, -0.98 < f7 / f < -0.88; -1.38 < R13 / f < -0.63; 1.18 < R14 / f < 6.29.

[0068] In some embodiments, the combined focal length f45 of the fourth lens and the fifth lens and the combined focal length f67 of the sixth lens and the seventh lens satisfy: -4.5 < f45 / f67 < -3.2; the combined focal length f456 of the fourth lens, the fifth lens and the sixth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: -6.6 < f456 / f567 < -3.1. Satisfying the above ranges can achieve the telephoto characteristics of the lens while correcting aberrations. At the same time, it helps to appropriately shorten the total length of the optical imaging lens and meet the requirements of lens thinning. More specifically, -4.1 < f45 / f67 < -3.5; -6.05 < f456 / f567 < -3.42.

[0069] In some embodiments, the object-side curvature radius R9 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R9 / f < 1.75; the image-side curvature radius R10 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R10 / f < 2.4. Satisfying the above ranges is beneficial for the smooth transition of light, better correcting the aberrations and distortions brought by the front lenses, and improving the overall imaging quality. More specifically, 0.87 < R9 / f < 1.6; 0.95 < R10 / f < 2.2.

[0070] In some embodiments, the object-side clear aperture sag Sag9 of the fifth lens and the object-side clear aperture d9 of the fifth lens satisfy: -0.4 < Sag9 / d9 < -0.1; the image-side clear aperture sag Sag10 of the fifth lens and the image-side clear aperture d10 of the fifth lens satisfy: -0.45 < Sag10 / d10 < 0. Satisfying the above ranges helps to control the trend of marginal field light and highlight the detailed information of the central field of the optical lens. More specifically, -0.31 < Sag9 / d9 < -0.21; -0.35 < Sag10 / d10 < -0.13.

[0071] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.8 < TTL / IH < 1. Satisfying the above ranges ensures that the lens has a larger image plane under the condition of the same total length, can match a larger-size imaging chip to achieve high-definition imaging, and better realizes the balance between the small total length and the large image plane of the lens. More specifically, 0.89 < TTL / IH < 0.92.

[0072] 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: 1.1 < IH / f < 1.4. Meeting the above range can not only achieve the telephoto characteristics of the lens to meet the local shooting requirements, but also achieve the large image plane characteristics of the lens, be able to match a larger size of the chip, and realize the high-pixel imaging of the lens. More specifically, 1.24 < IH / f < 2.08.

[0073] 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: 45° < (f × FOV) / IH < 55°. Meeting the above range can ensure that the optical lens has large field of view and large image plane characteristics by reasonably restricting the relationship between the focal length, field of view angle and image height of the optical lens, so that the optical lens has good optical performance and can capture the details of the object to be photographed well. More specifically, 50.2° < (f × FOV) / IH < 50.6°.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.8 < f1 / f < 1. Meeting the above range, by setting the first lens to have a large positive refractive power, the incident light can be converged to a large extent, and more light can enter the system, which is beneficial to improving the light input of the lens and realizing the large aperture performance of the lens, so that the lens can also achieve high-definition imaging in a relatively dark environment. More specifically, 0.89 < f1 / f < 0.93.

[0075] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -2.4 < f2 / f < -1.8. Meeting the above range makes the second lens have a negative optical power, which is beneficial to the smooth transition of light and improves the imaging resolution. More specifically, -2.21 < f2 / f < -1.99.

[0076] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 3.9 < f4 / f < 6.7. Meeting the above range is beneficial to slowing down the deflection degree of the incident light, avoiding excessive aberration caused by too strong refraction change, and at the same time is beneficial to balancing various aberrations generated by the front lens group and improving the overall imaging quality. More specifically, 4.29 < f4 / f < 6.1.

[0077] 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: 0.4 < R5 / f < 0.6; the effective focal length f of the optical lens and the curvature radius R6 of the image side surface of the third lens satisfy: 0.5 < R6 / f < 0.9. Satisfying the above ranges is beneficial to the further convergence of light rays, enabling the divergent light rays to smoothly enter the rear optical system, and better achieving high-quality imaging of the lens; at the same time, it can effectively correct the distortion of the edge field of view, reduce the degree of deformation of the edge of the captured image, and improve the image quality. More specifically, 0.45 < R5 / f < 0.5; 0.61 < R6 / f < 0.77.

[0078] In some embodiments, the effective focal length f of the optical lens and the curvature radius R7 of the object side surface of the fourth lens satisfy: -2.3 < R7 / f < -1.5; the curvature radius R8 of the image side surface of the fourth lens and the effective focal length f of the optical lens satisfy: -1.5 < R8 / f < -1. Satisfying the above conditions is beneficial to slowing down the deflection degree of the incident light rays, avoiding excessive aberration caused by too strong refraction changes, and at the same time is beneficial to balancing various aberrations generated by the front lens group and improving the overall imaging quality. More specifically, -2.08 < R7 / f < -1.72; -1.68 < R8 / f < -1.14.

[0079] In some embodiments, the curvature radius R8 of the image side surface of the fourth lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: -1.5 < R8 / R9 < -0.8; the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.6 < R9 / R10 < 1. Satisfying the above ranges can reduce the light deflection angle, make the light trend smoother; at the same time, it can correct coma and field curvature, improve the flatness of imaging, and improve the imaging quality of the optical lens. More specifically, -1.39 < R8 / R9 < -0.85; 0.72 < R9 / R10 < 0.93.

[0080] In some embodiments, the optical lens satisfies the conditional formula: 8.8 mm < f < 10.6 mm, 5.3 mm < EPD < 6.5 mm, 10 mm < TTL < 12.1 mm, 1.5 < Fno < 1.8, 33° < CRA < 44°, 1 mm < BFL < 1.6 mm, 57° < FOV < 69°, 11 mm < IH < 13.4 mm; where f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the principal ray angle of incidence at the maximum image height of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, and IH represents the true image height corresponding to the maximum field of view angle 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 miniaturization, large target surface, large field of view angle, large aperture, etc. More specifically, 9.71 mm < f < 9.77 mm, 5.88 mm < EPD < 5.93 mm, 10.97 mm < TTL < 11.08 mm, 1.6 < Fno < 1.7, 36.9° < CRA < 40.2°, 1.1 mm < BFL < 1.5 mm, 62.9° < FOV < 63.1°, 12.1 mm < IH < 12.2 mm.

[0081] 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. On the other hand, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristics of the glass itself. The optical lens provided by the present invention can adopt an all-plastic lens structure, which not only enables the lens to have excellent imaging performance, but also makes the structure of the lens relatively compact, and can better achieve the balance of lens miniaturization and high image quality.

[0082] 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 lens miniaturization. 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 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 lens miniaturization.

[0083] In each embodiment of the present invention, when the lens adopts an aspherical lens, the surface shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0084] ;

[0085] 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, H, I, and J are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order, eighteenth-order, and twentieth-order surface coefficients respectively.

[0086] 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.

[0087] Example 1

[0088] See also Figure 1 , which is a schematic diagram of the structure of the optical lens 100 provided in Embodiment 1 of the present invention, wherein the optical lens includes, in sequence from the object side to the imaging surface along the optical axis: an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and a filter G1.

[0089] The first lens L1 has positive refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0090] The second lens L2 has negative refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave;

[0091] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is concave;

[0092] The fourth lens L4 has positive refractive power, its object-side surface S7 is concave, and its image-side surface S8 is convex;

[0093] The fifth lens L5 has positive refractive power, an object-side surface S9 thereof is convex at the near optical axis, and an image-side surface S10 thereof is concave at the near optical axis;

[0094] The sixth lens L6 has negative refractive power, its object-side surface S11 is concave, and its image-side surface S12 is convex near the optical axis;

[0095] The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis;

[0096] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0097] The imaging surface S17 is a plane.

[0098] 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.

[0099] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0100] Table 1-1

[0101]

[0102] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0103] Table 1-2

[0104]

[0105] Figure 2 The field curvature curve of the optical lens 100 in this embodiment is shown, which indicates the degree of curvature of light in the meridional image plane and the sagittal image plane, the horizontal axis indicates the offset (unit: mm), and the vertical axis indicates 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 ±0.08mm, indicating that the optical lens 100 can correct the field curvature well.

[0106] Figure 3 The F-Tan (Theta) distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion of different field angles on the imaging plane, 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 value is controlled within ±2%, indicating that the optical lens 100 can correct the distortion well.

[0107] 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 plane, 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 ±0.04mm, indicating that the optical lens 100 can better correct the axial aberration.

[0108] 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 ±1 μm, indicating that the optical lens 100 can correct the chromatic aberration well.

[0109] Figure 6 The modulation transfer function (MTF) curve of the optical lens 100 in this embodiment is shown, which represents the imaging modulation degree of the lens at different spatial frequencies in each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.3 in the whole field of view, and in the range of 0 to 300 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0110] Example 2

[0111] See also Figure 7 , which 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 image side surface S12 of the sixth lens L6 is a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0112] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0113] Table 2-1

[0114]

[0115] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0116] Table 2-2

[0117]

[0118] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and MTF curve of the optical lens 200 are shown in FIG. Figure 8 , Fig. 9 , Fig.10 , Fig.11 , Fig.12 shown.

[0119] from Figure 8It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.09 mm, indicating that the optical lens 200 can correct the field curvature well.

[0120] from Fig. 9 It can be seen that the distortion value is controlled within ±2%, indicating that the optical lens 200 can correct the distortion well.

[0121] from Fig.10 It can be seen that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0122] from Fig.11 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0123] from Fig.12 It can be seen that the MTF value of this embodiment is above 0.3 in the whole field of view. In the range of 0 to 300 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution capability in both low-frequency and high-frequency conditions.

[0124] Example 3

[0125] See also Fig.13 , 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 S11 of the sixth lens L6 is a convex surface at the near optical axis; the image-side surface S12 of the sixth lens L6 is a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0126] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0127] Table 3-1

[0128]

[0129] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0130] Table 3-2

[0131]

[0132] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and MTF curve of the optical lens 300 are shown as follows: Fig.14 , Fig.15 , Fig.16 , Fig.17 , Fig.18 shown.

[0133] from Fig.14 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 300 can correct the field curvature well.

[0134] from Fig.15 It can be seen that the distortion value is controlled within ±1.5%, indicating that the optical lens 300 can correct the distortion well.

[0135] from Fig.16 It can be seen that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0136] from Fig.17 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0137] from Fig.18 It can be seen that the MTF value of this embodiment is above 0.3 in the whole field of view. In the range of 0 to 300 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution capability in both low-frequency and high-frequency conditions.

[0138] 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.

[0139] Table 4

[0140]

[0141] In summary, the optical lens provided by the present invention has at least the following advantages:

[0142] (1) It can effectively shorten the overall length of the optical lens, which is conducive to making the equipment smaller and lighter. At the same time, it has a large field of view, so that more scene information can be obtained, meeting the needs of wide-range shooting.

[0143] (2) The lens has a large aperture, which enables high-definition imaging even in dim environments; it can also realize the large target surface characteristics of the lens and can be matched with a 1-inch ultra-large bottom COMS chip, which is beneficial to improving the lens resolution and image detail restoration.

[0144] (3) The lens has a telephoto feature, which can achieve a shooting experience of bringing distant scenes closer, which is conducive to better achieving the shooting effect of a small depth of field, blurring the background and highlighting the subject; at the same time, it can also reasonably correct the overall aberration of the optical lens, making the optical lens have high pixels and improving the imaging quality of the optical lens.

[0145] 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.

[0146] 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 positive optical power, whose object side is convex and whose image side is concave; A second lens with negative optical power, whose object side is convex and whose image side is concave; A third lens with positive optical power, whose object side is convex and whose image side is concave; A fourth lens with positive optical power, whose object side is concave and whose image side is convex; A fifth lens with positive optical power, whose object side is convex near the optical axis; whose image side is concave near the optical axis; A sixth lens with negative optical power; A seventh lens with negative optical power, whose object side is concave 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: -0.7 < (R9 - R10) / (R9 + R10) < 0; the curvature radius R7 of the object side of the fourth lens and the curvature radius R8 of the image side of the fourth lens satisfy: 3.5 < (R7 + R8) / (R7 - R8) < 5.5; the combined focal length f45 of the fourth lens and the fifth lens and the combined focal length f67 of the sixth lens and the seventh lens satisfy: -4.5 < f45 / f67 < -3.2; the combined focal length f456 of the fourth lens, the fifth lens and the sixth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: -6.6 < f456 / f567 < -3.

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: 1 < TTL / f < 1.3; the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 34° < FOV / Fno < 42°; the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.85 < IH / EPD < 2.

25.

3. The optical lens according to claim 1, characterized in that: The true image height IH corresponding to the maximum field of view of the optical lens and the back focal length BFL of the optical lens satisfy: 7.6 < IH / BFL < 11.6; the clear aperture semi-diameter d7 of the object side of the fourth lens and the clear aperture semi-diameter d1 of the object side of the first lens satisfy: 0.6 < d7 / d1 < 0.

75.

4. 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: 2.1 < f3 / f < 3.3; 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: -7.5 < (R5 + R6) / (R5 - R6) < -4.

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: 7.3 < f5 / f < 12.6; the curvature radius R9 of the object side of the fifth lens, the central thickness CT5 of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: 0.5 < (R9 - CT5) / R10 < 1.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -28.7 < f6 / f < -7.1; the image-side curvature radius R12 of the sixth lens and the object-side curvature radius R13 of the seventh lens satisfy: 0.6 < (R12 - R13) / (R12 + R13) < 1.

6.

7. 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: -1.1 < f7 / f < -0.8; the effective focal length f of the optical lens and the object-side curvature radius R13 of the seventh lens satisfy: -1.5 < R13 / f < -0.5; the effective focal length f of the optical lens and the image-side curvature radius R14 of the seventh lens satisfy: 1 < R14 / f < 6.

9.

8. The optical lens according to claim 1, characterized in that: The object-side curvature radius R9 and the image-side curvature radius R10 of the fifth lens satisfy: -0.17 < (R9 - R10) / (R9 + R10) < -0.03; the object-side curvature radius R7 and the image-side curvature radius R8 of the fourth lens satisfy: 3.86 < (R7 + R8) / (R7 - R8) < 5.05; the combined focal length f45 of the fourth lens and the fifth lens and the combined focal length f67 of the sixth lens and the seventh lens satisfy: -4.1 < f45 / f67 < -3.5; the combined focal length f456 of the fourth lens, the fifth lens and the sixth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: -6.05 < f456 / f567 < -3.

42.

9. The optical lens according to claim 1, characterized in that: The object-side curvature radius R9 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R9 / f < 1.75; the image-side curvature radius R10 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.8 < R10 / f < 2.

4.

10. The optical lens according to claim 1, characterized in that: The object-side clear aperture sagittal height Sag9 and the object-side clear aperture diameter d9 of the fifth lens satisfy: -0.4 < Sag9 / d9 < -0.1; the image-side clear aperture sagittal height Sag10 and the image-side clear aperture diameter d10 of the fifth lens satisfy: -0.45 < Sag10 / d10 < 0.

Images