Optical lens

Abstract

The application provides an optical lens, which comprises six lenses in sequence along an optical axis from an object side to an imaging surface, and the six lenses comprise: a first lens with positive focal power, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; a second lens with positive focal power, wherein the image side surface of the second lens is a convex surface; a third lens with negative focal power, wherein the object side surface of the third lens is a concave surface; a fourth lens with positive focal power, wherein the image side surface of the fourth lens is a convex surface; a fifth lens with positive focal power, wherein the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a convex surface; and a sixth lens with negative focal power, wherein the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface at a near optical axis. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration and improve the imaging quality of the optical lens through specific surface shape matching and reasonable focal power distribution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] In recent years, as consumers continue to demand higher quality smartphone photography. 6P optical lenses are increasingly widely used, not only in high-end models, but also in many low-end phones, to improve their market competitiveness. 6P optical lenses still occupy a dominant position in the market due to their cost-effectiveness and good performance. At the same time, consumers' demand for camera performance is constantly increasing, and a large aperture and a large image area can bring more light and better image quality. At the same time, in order to make the phone portable and beautiful, the optical lens also requires a small and thin shape, which makes the lens design difficulty increase exponentially. How to achieve large aperture and high pixel requirements while maintaining the miniaturization of the lens is also a difficulty in lens design at this stage. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens with excellent imaging quality.

[0004] The technical scheme adopted by the present application is:

[0005] An optical lens, a total of six lenses, including in order along the optical axis from the object side to the imaging surface:

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

[0007] The second lens has positive focal power, and the image side surface is convex;

[0008] The third lens has negative focal power, and the object side surface is concave;

[0009] The fourth lens has positive focal power, and the image side surface is convex;

[0010] The fifth lens has positive focal power, the object side surface is concave, and the image side surface is convex;

[0011] The sixth lens has negative focal power, the object side surface is concave, and the image side surface is concave near the optical axis;

[0012] Wherein, the combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: 1.1<f123 / f<1.3; the curvature radius R6 of the image side surface of the third lens, the curvature radius R7 of the object side surface of the fourth lens and the effective focal length f of the optical lens satisfy: 37<(R6+R7) / f<68.

[0013] Further preferably, the effective focal length f, the maximum field of view FOV and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 1 < (IH / 2) / (f*tan(FOV / 2)) < 1.03; the half aperture radius d1 of the object side of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens and the maximum field of view FOV of the optical lens satisfy: 0.3 < d1 / (IH / 2) / tan(FOV / 2) < 0.4.

[0014] Further preferably, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 53° < FOV / Fno < 57°; the real 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: 3 < IH / EPD < 3.3.

[0015] Further preferably, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 1.8 < IH / f < 2.1; the real 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 < IH / BFL < 8.

[0016] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.4 < f5 / f < 0.6; the radius of curvature R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: -12.2 < R9 / f < -3.7; the radius of curvature R10 of the image side of the fifth lens and the effective focal length f of the optical lens satisfy: -0.4 < R10 / f < -0.2.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -0.4 < f6 / f < -0.3; the radius of curvature R11 of the object side of the sixth lens and the effective focal length f of the optical lens satisfy: -0.7 < R11 / f < -0.4; the radius of curvature R12 of the image side of the sixth lens and the effective focal length f of the optical lens satisfy: 0.35 < R12 / f < 0.5.

[0018] Further preferably, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 < f3 / f4 < -0.2; the radius of curvature R6 of the image side of the third lens and the radius of curvature R7 of the object side of the fourth lens satisfy: -25 < R6 / R7 < 0.

[0019] Further preferably, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -1.2 < f2 / f3 < -1; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: -1.1 < R4 / f < -0.7; and the curvature radius R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: -1.3 < R5 / f < -0.6.

[0020] Further preferably, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1.5 < f5 / f6 < -1.3; the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface satisfy: 13.1 < R9 / R10 < 36.5; and the curvature radius R10 of the image side surface of the fifth lens and the curvature radius R11 of the object side surface of the sixth lens satisfy: 0.5 < R10 / R11 < 0.7.

[0021] Further preferably, the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface satisfy: 0.8 < (R9-R10) / (R9+R10) < 1; and the curvature radius R11 of the object side surface of the sixth lens and the curvature radius R12 of the image side surface satisfy: 0 < (R11-R12) / (R11+R12) < 0.2.

[0022] The image side surface of the third lens is convex, and the object side surface of the fourth lens is convex at the near optical axis; or the image side surface of the third lens is concave at the near optical axis, and the object side surface of the fourth lens is concave.

[0023] Compared with the prior art, the optical lens provided by the application adopts six lenses with specific focal lengths, and through specific surface shape settings and reasonable focal length distribution, the lens can have the characteristics of large image surface and large aperture. The large image surface helps to improve the resolving power of the lens, and the large aperture enables the lens to have excellent imaging quality in a dark environment at night. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and / or additional aspects and advantages of the application will become apparent and be readily understood from the following description, taken in connection with the accompanying drawings, in which:

[0025] Figure 1 FIG. 1 is a structural schematic diagram of an optical lens according to an embodiment of the application.

[0026] Figure 2 FIG. 2 is a field curvature curve of the optical lens according to the embodiment of the application.

[0027] Figure 3 FIG. 3 is an F-Tan(Theta) distortion curve of the optical lens according to the embodiment of the application.

[0028] Figure 4 A curve graph of the optical lens in the embodiment 1 of the present application is shown in FIG. 6.

[0029] Figure 5 A curve graph of the optical lens in the embodiment 1 of the present application is shown in FIG. 6.

[0030] Figure 6 A structure diagram of the optical lens in the embodiment 2 of the present application is shown in FIG. 10.

[0031] Figure 7 A curve graph of the optical lens in the embodiment 2 of the present application is shown in FIG. 14.

[0032] Figure 8 A curve graph of the optical lens in the embodiment 2 of the present application is shown in FIG. 14.

[0033] Figure 9 A curve graph of the optical lens in the embodiment 2 of the present application is shown in FIG. 14.

[0034] Figure 10 A curve graph of the optical lens in the embodiment 2 of the present application is shown in FIG. 14.

[0035] Figure 11 A structure diagram of the optical lens in the embodiment 3 of the present application is shown in FIG. 18.

[0036] Figure 12 A curve graph of the optical lens in the embodiment 3 of the present application is shown in FIG. 22.

[0037] Figure 13 A curve graph of the optical lens in the embodiment 3 of the present application is shown in FIG. 22.

[0038] Figure 14 A curve graph of the optical lens in the embodiment 3 of the present application is shown in FIG. 22.

[0039] Figure 15 A curve graph of the optical lens in the embodiment 3 of the present application is shown in FIG. 22.

[0040] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0041] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It is to be understood that the detailed description is merely descriptive of embodiments of the present application and is not intended to limit the scope of the present application in any way. Throughout the specification, like reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

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

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

[0044] In the present specification, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the position of the convex surface is not specified, 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 specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0045] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", when used in this specification, specify the presence of stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. In addition, when expressions such as "at least one of" appear after a list of one or more items, the phrase "at least one of" modifies the entire list of items and does not modify the list of items individually. Furthermore, when describing embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the word "exemplary" is intended to mean an example or an illustration.

[0046] Unless otherwise defined, all terms used in this specification, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that the terms should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0047] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0048] The optical lens provided by the embodiments of the present application comprises six lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface, i.e., the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens.

[0049] In some embodiments, the first lens can have positive refractive power, the object side surface thereof can be convex, and the image side surface thereof can be concave. The second lens can have positive refractive power, the object side surface thereof can be concave or convex at the near optical axis, and the image side surface thereof can be concave. The third lens can have negative refractive power, the object side surface thereof can be concave, and the image side surface thereof can be convex or concave at the near optical axis. The fourth lens can have positive refractive power, the object side surface thereof can be concave or convex at the near optical axis, and the image side surface thereof can be convex. The fifth lens can have positive refractive power, the object side surface thereof can be concave, and the image side surface thereof can be convex. The sixth lens can have negative refractive power, the object side surface thereof can be concave, and the image side surface thereof can be concave at the near optical axis.

[0050] In some embodiments, the image side surface of the third lens can be convex, and the object side surface of the fourth lens can be convex at the near optical axis; or the image side surface of the third lens can be concave at the near optical axis, and the object side surface of the fourth lens can be concave at the near optical axis.

[0051] In some embodiments, the optical lens can further include a diaphragm, which can be located between the object side and the first lens. It can be understood that the diaphragm can be used to limit the amount of light to change the brightness of the imaging.

[0052] In some embodiments, the optical lens can further include a filter, which can be arranged between the sixth 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.

[0053] In some embodiments, the combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: 1.1 < f123 / f < 1.3; the curvature radius R6 of the image side surface of the third lens, the curvature radius R7 of the object side surface of the fourth lens and the effective focal length f of the optical lens satisfy: 37 < (R6+R7) / f < 68. By reasonably distributing the refractive power of the front lens group of the optical lens and limiting the surface shape of the image side surface of the third lens and the object side surface of the fourth lens, the optical total length of the optical lens can be effectively shortened, which is conducive to the miniaturization and lightness of the optical lens, and the degree of deflection of light can be reasonably controlled, which is conducive to improving the imaging effect of the optical lens. More specifically, 1.15 < f123 / f < 1.26, 37.76 < (R6+R7) / f < 67.98.

[0054] In some embodiments, the effective focal length f, the maximum field of view FOV, and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 1 < (IH / 2) / (f*tan(FOV / 2)) < 1.03; the object side half entrance pupil diameter d1 of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens, and the maximum field of view FOV of the optical lens satisfy: 0.3 < d1 / (IH / 2) / tan(FOV / 2) < 0.4. Satisfying the above ranges indicates that the optical distortion of the optical lens is better controlled, so that the imaging of each field of view is clearer, and the resolving power of the optical lens is improved; and by reasonably controlling the relationship among the front end diameter, the real image height corresponding to the maximum field of view, and the maximum field of view of the optical lens, the small head requirement of the optical lens is met, and the structural rationality of the optical lens is improved. More specifically, 0.3 < d1 / (IH / 2) / tan(FOV / 2) < 0.36.

[0055] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 53° < FOV / Fno < 57°; the real 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: 3 < IH / EPD < 3.3. Satisfying the above ranges makes the aperture match the field of view, which is beneficial to expand the field of view of the optical lens and increase the aperture of the optical lens, so as to obtain more picture information, meet the demand of large-range detection, and the large-aperture feature can enable the optical lens to shoot in a darker environment, while helping to blur the background and make the subject more prominent; and the width of the light beam entering the optical lens at different field angles is reasonable, so that the brightness of the optical lens at the image plane is improved, dark corners are avoided, and the image height of the optical lens is also increased, which is beneficial to the rear-end chip to obtain more picture information and reduce the information processing pressure of the rear-end chip. More specifically, 53.74° < FOV / Fno < 56.97°, 3.02 < IH / EPD < 3.23.

[0056] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 1.8 < IH / f < 2.1; the real 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 < IH / BFL < 8. Satisfying the above ranges can realize the large image surface feature, match the large-size chip, and improve the imaging quality of the optical lens. More specifically, 1.88 < IH / f < 2.05, 7.17 < IH / BFL < 7.43.

[0057] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.4 < f5 / f < 0.6; the curvature radius R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: -12.2 < R9 / f < -3.7; and the curvature radius R10 of the image side of the fifth lens and the effective focal length f of the optical lens satisfy: -0.4 < R10 / f < -0.2. Satisfying the above ranges, by reasonably limiting the focal length ratio of the fifth lens and the shape of the object side and the image side of the fifth lens, the degree of deflection of light is controlled, and the imaging quality of the optical lens is improved. More specifically, 0.45 < f5 / f < 0.54, -12.12 < R9 / f < -3.76, and -0.34 < R10 / f < -0.28.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -0.4 < f6 / f < -0.3; the curvature radius R11 of the object side of the sixth lens and the effective focal length f of the optical lens satisfy: -0.7 < R11 / f < -0.4; and the curvature radius R12 of the image side of the sixth lens and the effective focal length f of the optical lens satisfy: 0.35 < R12 / f < 0.5. Satisfying the above ranges, by reasonably limiting the focal length ratio of the sixth lens and the shape of the object side and the image side of the sixth lens, the light trend and the incidence angle of light relative to the image side are reasonably adjusted, the sensitivity of the optical lens is reduced, the imaging quality of the optical lens is improved, and large image characteristics are also achieved. More specifically, -0.4 < f6 / f < -0.32, -0.63 < R11 / f < -0.48, and 0.39 < R12 / f < 0.48.

[0059] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 < f3 / f4 < -0.2; and the curvature radius R6 of the image side of the third lens and the curvature radius R7 of the object side of the fourth lens satisfy: -25 < R6 / R7 < 0. Satisfying the above ranges, by reasonably limiting the focal length ratio of the third lens and the fourth lens and the shape of the image side of the third lens and the object side of the fourth lens, various aberrations of the optical lens are corrected, the imaging quality of the optical lens is improved, and the picture clarity is improved. More specifically, -0.5 < f3 / f4 < -0.24, and -24.83 < R6 / R7 < -0.04.

[0060] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -1.2 < f2 / f3 < -1; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: -1.1 < R4 / f < -0.7; and the curvature radius R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: -1.3 < R5 / f < -0.6. Satisfying the above ranges, by reasonably limiting the focal length ratio of the second lens and the third lens, and the shape of the image side surface of the second lens and the object side surface of the third lens, the field curvature can be reduced, and the difficulty of aberration correction of the rear end lens is reduced. More specifically, -1.16 < f2 / f3 < -1.03, -1.05 < R4 / f < -0.72, and -1.26 < R5 / f < -0.66.

[0061] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1.5 < f5 / f6 < -1.3; the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface satisfy: 13.1 < R9 / R10 < 36.5; and the curvature radius R10 of the image side surface of the fifth lens and the curvature radius R11 of the object side surface of the sixth lens satisfy: 0.5 < R10 / R11 < 0.7. Satisfying the above ranges, by reasonably limiting the focal length ratio of the fifth lens and the sixth lens, and the shape of the object side surface of the fifth lens, the image side surface of the fifth lens, and the object side surface of the sixth lens, the aberration of the edge field of view can be corrected, and the imaging quality of the edge field of view is improved. More specifically, -1.46 < f5 / f6 < -1.33, 13.16 < R9 / R10 < 36.47, and 0.5 < R10 / R11 < 0.64.

[0062] In some embodiments, the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface satisfy: 0.8 < (R9-R10) / (R9+R10) < 1; and the curvature radius R11 of the object side surface of the sixth lens and the curvature radius R12 of the image side surface satisfy: 0 < (R11-R12) / (R11+R12) < 0.2. Satisfying the above ranges, by reasonably limiting the shape of the object side surface and the image side surface of the fifth lens, and the object side surface and the image side surface of the sixth lens, the degree of deflection of light can be reasonably controlled, the aberration is reduced, and the imaging quality is improved. More specifically, 0.85 < (R9-R10) / (R9+R10) < 0.96, and 0.01 < (R11-R12) / (R11+R12) < 0.17.

[0063] In some embodiments, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 < TTL / f < 1.4; the total track length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.6 < TTL / IH < 0.7. Satisfying the above ranges, while good imaging quality is taken into account, the total length of the optical lens is shortened, the optical lens is miniaturized, and the demand for miniaturization and large image surface in the mobile phone application scenario is met. More specifically, 1.27 < TTL / f < 1.33, and 0.64 < TTL / IH < 0.69.

[0064] In some embodiments, the sum ∑CT of the center thicknesses of the first lens to the sixth lens along the optical axis and the total track length TTL of the optical lens satisfy: 0.6 < ∑CT / TTL < 0.7, and the sum ∑CT of the center thicknesses of the first lens to the sixth lens along the optical axis and the effective focal length f of the optical lens satisfy: 0.8 < ∑CT / f < 0.9. Satisfying the above ranges, high-pixel characteristics can be achieved, the imaging quality of the optical lens is improved, and the processability of each lens is facilitated, thereby reducing production costs. More specifically, 0.62 < ∑CT / TTL < 0.66, and 0.81 < ∑CT / f < 0.84.

[0065] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 1.1 < f1 / f < 1.3. Satisfying the above range, the first lens can have appropriate positive refractive power, which is conducive to the convergence of light and the optimization of aberration and the improvement of resolution. More specifically, 1.1 < f1 / f < 1.24.

[0066] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.3 < f2 / f < 1.9. Satisfying the above range, the second lens can have appropriate positive refractive power, which can reduce the influence of spherical aberration and astigmatism on the optical lens and improve the imaging quality of the optical lens. More specifically, 1.36 < f2 / f < 1.9.

[0067] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -1.9 < f3 / f < -1.2. Satisfying the above range, the third lens can have appropriate negative refractive power, which is conducive to balancing various types of aberrations generated by the optical lens and improving the imaging quality of the optical lens. More specifically, -1.82 < f3 / f < -1.26.

[0068] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 3.3 < f4 / f < 5.1, and the curvature radius R8 of the image side surface of the fourth lens and the effective focal length f of the optical lens satisfy: -3.6 < R8 / f < -1.2. Satisfying the above ranges can make the fourth lens have appropriate positive refractive power, reasonably control the shape of the image side surface of the fourth lens, reduce the spherical aberration and coma generated by itself, and improve the imaging quality of the optical lens. More specifically, 3.33 < f4 / f < 5.02, and -3.51 < R8 / f < -1.2.

[0069] In some embodiments, the edge interval ET12 of the first lens and the second lens, the edge interval ET23 of the second lens and the third lens, the edge interval ET34 of the third lens and the fourth lens, the edge interval ET45 of the fourth lens and the fifth lens, the edge interval ET56 of the fifth lens and the sixth lens, and the total track length TTL of the optical lens satisfy: 0 < (ET12+ET23+ET34+ET45+ET56) / TTL < 0.1. Satisfying the above range can reduce the edge interval between adjacent lenses, make the optical lens structure compact, and reduce the number of assembly spacers and the production cost of the optical lens. More specifically, 0.05 < (ET12+ET23+ET34+ET45+ET56) / TTL < 0.1.

[0070] In some embodiments, the half-field radius sag6 of the image side surface of the third lens and the half-field radius d6 satisfy: -0.2 < sag6 / d6 < -0.1, and the half-field radius sag7 of the object side surface of the fourth lens and the half-field radius d7 satisfy: -0.2 < sag7 / d7 < -0.1. Satisfying the above ranges can effectively improve the imaging quality of the edge field and the imaging quality of the optical lens by reasonably controlling the half-field radius and the corresponding sag of the image side surface of the third lens and the half-field radius and the corresponding sag of the object side surface of the fourth lens. More specifically, -0.16 < sag6 / d6 < -0.1, and -0.2 < sag7 / d7 < -0.18.

[0071] In some embodiments, the optical lens satisfies the condition formula: 4.2mm<f<4.6mm, 85°<FOV<91°, 2.6mm<EPD<2.9mm, 5.5mm<TTL<5.9mm, 1.5<Fno<1.7, 8.5mm<IH<8.7mm, 37°<CRA<39°, 1.1mm<BFL<1.3mm; wherein f represents an effective focal length of the optical lens, FOV represents a maximum field of view angle of the optical lens, EPD represents an entrance pupil diameter of the optical lens, TTL represents an optical total length of the optical lens, Fno represents an aperture value of the optical lens, IH represents an image height corresponding to the maximum field of view angle of the optical lens, CRA represents a chief ray angle of incidence at the maximum image height of the optical lens, and BFL represents a back focal length of the optical lens. Satisfying the above condition indicates that the optical lens provided by the embodiments of the present application at least has the characteristics of small volume, large image surface, and large aperture. More specifically, 4.22mm<f<4.55mm, 85.9°<FOV<90.1°, 2.66mm<EPD<2.85mm, 5.56mm<TTL<5.83mm, 1.57<Fno<1.61, 8.56mm<IH<8.63mm, 37.65°<CRA<38.52°, 1.14mm<BFL<1.21mm.

[0072] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens in the optical lens provided by the present application all adopt plastic lenses.

[0073] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth 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 achieving the miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens in the present application all can 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 achieving the miniaturization of the lens.

[0074] In various embodiments of the present application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[0075]

[0076] Wherein, z is the distance from the vertex of the aspheric surface to the position of the aspheric surface along the optical axis at a height of h, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, B, C, D, E, F, G, H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order surface coefficients, respectively.

[0077] The application will be further described in the following embodiments. In each embodiment, the thickness, the radius of curvature, and the material selection of each lens in the optical lens are different, and the specific differences can be referred to the parameter table of each embodiment. The following embodiments are merely the preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, and any change, substitution, combination or simplification made without departing from the innovative points of the application should be regarded as equivalent replacement, and all are included in the protection scope of the application.

[0078] Embodiment 1

[0079] Please refer to Figure 1 , which is a structural schematic diagram of the optical lens 100 provided in the embodiment 1 of the application. The optical lens 100 includes, along the optical axis from the object side to the imaging surface, a diaphragm 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, and a filter G1.

[0080] The first lens L1 has positive focal power, the object side surface S1 is a convex surface, and the image side surface S2 is a concave surface.

[0081] The second lens L2 has positive focal power, the object side surface S3 is a concave surface, and the image side surface S4 is a convex surface.

[0082] The third lens L3 has negative focal power, the object side surface S5 is a concave surface, and the image side surface S6 is a convex surface.

[0083] The fourth lens L4 has positive focal power, the object side surface S7 is a convex surface at the near optical axis, and the image side surface S8 is a convex surface.

[0084] The fifth lens L5 has positive focal power, the object side surface S9 is a concave surface, and the image side surface S10 is a convex surface.

[0085] The sixth lens L6 has negative focal power, the object side surface S11 is a concave surface, and the image side surface S12 is a concave surface at the near optical axis.

[0086] The object side surface S13 and the image side surface S14 of the filter G1 are both flat surfaces.

[0087] The imaging surface S15 is a flat surface.

[0088] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 are plastic aspherical lenses.

[0089] The related parameters of the lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0090] Table 1-1

[0091]

[0092] The surface parameters of the aspherical lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0093] Table 1-2

[0094]

[0095]

[0096] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve, the axial chromatic aberration curve and the axial aberration curve of the optical lens 100 are shown in FIGS. Figure 2 、 Figure 3 、 Figure 4 、 Figure 5

[0097] Figure 2 The field curvature curve of Embodiment 1 is shown, which represents the curvature of the meridional image surface and the sagittal image surface of light rays of different wavelengths, 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 surface and the sagittal image surface is controlled within -0.1mm-0.2mm, which shows that the optical lens can well correct the field curvature.

[0098] Figure 3 The F-Tan(Theta) distortion curve of Embodiment 1 is shown, which represents the distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within ±1%, which shows that the optical lens can well correct the distortion.

[0099] Figure 4 The axial 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 (0.555μm) at different image heights on the imaging surface, the horizontal axis represents the axial 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 axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1.5μm-1μm, which shows that the optical lens can well correct the chromatic aberration.​

[0100] Figure 5 The axial aberration curve of the optical lens 100 in the 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. As can be seen from the figure, the offset of the axial aberration is controlled within ±0.05 mm, which shows that the optical lens can better correct the axial aberration.

[0101] Embodiment 2

[0102] Please refer to Figure 6 , which is a structural schematic diagram of the optical lens 200 provided in the embodiment 2 of the application. Compared with the embodiment 1, the main difference is that the image side S6 of the third lens L3 is concave at the near optical axis, the object side S7 of the fourth lens L4 is concave, and the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0103] The related parameters of each lens in the optical lens 200 in the embodiment 2 are shown in Table 2-1.

[0104] Table 2-1

[0105]

[0106] The surface type parameters of the aspheric lens of the optical lens 200 in the embodiment 2 are shown in Table 2-2.

[0107] Table 2-2

[0108]

[0109]

[0110] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve, the vertical axis chromatic aberration curve and the axial aberration curve of the optical lens 200 are shown in Figure 7 , Figure 8 , Figure 9 , Figure 10 respectively.

[0111] As can be seen from Figure 7 , the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.2 mm, which shows that the optical lens can well correct the field curvature.

[0112] As can be seen from Figure 8 , the distortion of the optical lens is controlled within ±1%, which shows that the optical lens can well correct the distortion.

[0113] As can be seen from Figure 9It can be seen from the table that the sagittal and tangential field curves of the optical lens 300 are controlled within ±0.2mm, which indicates that the optical lens can correct the field curvature well.

[0114] From Figure 10 It can be seen from the table that the axial aberration offset of the optical lens 300 is controlled within ±0.05mm, which indicates that the optical lens can correct the axial aberration well.

[0115] Embodiment 3

[0116] Please refer to Figure 11 , which is a structural schematic diagram of the optical lens 300 provided in Embodiment 3 of the present application. Compared with Embodiment 1, the main difference is that the object side S3 of the second lens L2 is a convex surface near the optical axis, the image side S6 of the third lens L3 is a concave surface near the optical axis, the object side S7 of the fourth lens L4 is a concave surface, and the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0117] The related parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0118] Table 3-1

[0119]

[0120]

[0121] The surface type parameters of the aspherical lens of the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0122] Table 3-2

[0123]

[0124]

[0125] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve, the sagittal color aberration curve and the axial aberration curve of the optical lens 300 are shown in Figure 12 , Figure 13 , Figure 14 , Figure 15 respectively.

[0126] From Figure 12 It can be seen from the table that the sagittal and tangential field curves of the optical lens 300 are controlled within ±0.2mm, which indicates that the optical lens can correct the field curvature well.

[0127] From Figure 13 It can be seen from the table that the distortion of the optical lens is controlled within -0.5%~1.5%, which indicates that the optical lens can correct the distortion well.

[0128] From Table 2, it can be seen that the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, which indicates that the optical lens can better correct chromatic aberration. Figure 14

[0129] From Table 3, it can be seen that the shift of the axial aberration is controlled within -0.08 mm-0.05 mm, which indicates that the optical lens can better correct axial aberration. Figure 15

[0130] Referring to Table 4, the optical characteristics corresponding to the above-mentioned embodiments are shown, including the effective focal length f, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view, the maximum field of view FOV of the optical lens, and the numerical value corresponding to each conditional expression in each embodiment.

[0131] Table 4

[0132]

[0133]

[0134] In summary of the above embodiments, the optical lens provided by the present application can improve the imaging quality of the optical lens, reduce aberration, and improve the imaging quality of the optical lens by specific surface shape setting and reasonable power distribution, so that the optical lens has the advantages of miniaturization, high pixel, low distortion, etc., and meets the development of mobile devices which are increasingly miniaturized and high-performance. The total optical length is small, which is conducive to better miniaturization and lightness; the large aperture means that the optical lens can be used for shooting in a dark environment, and is also conducive to background blurring, so that the main body is more prominent; the small edge distance between any two lenses can reduce the assembly spacer and reduce the cost of the whole lens; the low distortion can provide more accurate and clear imaging effect.

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

[0136] ​​The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical lens, six pieces of lenses in total, characterized in that, In order from the object side to the imaging surface along the optical axis, sequentially comprise: a first lens with positive refractive power, the object side surface of which is convex, and the image side surface of which is concave; a second lens with positive refractive power, the image side surface of which is convex; a third lens with negative refractive power, the object side surface of which is concave; a fourth lens with positive refractive power, the image side surface of which is convex; a fifth lens with positive refractive power, the object side surface of which is concave, and the image side surface of which is convex; a sixth lens with negative refractive power, the object side surface of which is concave, and the image side surface of which is concave at the near optical axis; wherein the combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: 1.1 < f123 / f < 1.3; the curvature radius R6 of the image side surface of the third lens, the curvature radius R7 of the object side surface of the fourth lens and the effective focal length f of the optical lens satisfy: 37 < (R6+R7) / f < 68; the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 53° < FOV / Fno < 57°; the real 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: 3 < IH / EPD < 3.

3.

2. The optical lens of claim 1, wherein, The effective focal length f, the maximum field of view FOV and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 1 < (IH / 2) / (f*tan(FOV / 2)) < 1.03; the object side surface half light entrance radius d1 of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens and the maximum field of view FOV of the optical lens satisfy: 0.3 < d1 / (IH / 2) / tan(FOV / 2) < 0.

4.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1.1 < f1 / f < 1.

3.

4. The optical lens of claim 1, wherein, The real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 1.8 < IH / f < 2.1; the real 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 < IH / BFL < 8.

5. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.4 < f5 / f < 0.6; the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -12.2 < R9 / f < -3.7; the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -0.4 < R10 / f < -0.

2.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -0.4 < f6 / f < -0.3; the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens satisfy: -0.7 < R11 / f < -0.4; the curvature radius R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.35 < R12 / f < 0.

5.

7. The optical lens of claim 1, wherein, The focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 < f3 / f4 < -0.2; the radius of curvature R6 of the image side surface of the third lens and the radius of curvature R7 of the object side surface of the fourth lens satisfy: -25 < R6 / R7 < 0.

8. The optical lens of claim 1, wherein, The focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -1.2 < f2 / f3 < -1; the radius of curvature R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: -1.1 < R4 / f < -0.7; the radius of curvature R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: -1.3 < R5 / f < -0.

6.

9. The optical lens of claim 1, wherein, The focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -1.5 < f5 / f6 < -1.3; 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 satisfy: 13.1 < R9 / R10 < 36.5; the radius of curvature R10 of the image side surface of the fifth lens and the radius of curvature R11 of the object side surface of the sixth lens satisfy: 0.5 < R10 / R11 < 0.

7.

10. The optical lens of claim 1, wherein, 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 satisfy: 0.8 < (R9-R10) / (R9+R10) < 1; the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface satisfy: 0 < (R11-R12) / (R11+R12) < 0.

2. The image side surface of the third lens is a convex surface, and the object side surface of the fourth lens is a convex surface at the near optical axis; or the image side surface of the third lens is a concave surface at the near optical axis, and the object side surface of the fourth lens is a concave surface.

Images