Optical lens

Abstract

The application provides an optical lens, which comprises six lenses arranged along an optical axis from an object side to an imaging surface in sequence, wherein the first lens has a negative focal power, 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; the second lens has a positive focal power, the object side surface and the image side surface of the second lens are both convex surfaces; the third lens has a positive focal power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the fourth lens has a negative focal power, the object side surface and the image side surface of the fourth lens are both concave surfaces; the fifth lens has a positive focal power, the object side surface and the image side surface of the fifth lens are both convex surfaces; and the sixth lens has a negative focal power, the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a concave surface; and the effective focal length f of the optical lens and the image side surface curvature radius R6 of the third lens satisfy the condition R6 / f>14.0. The optical lens provided by the application improves the resolving power of the optical lens, reduces aberration, and improves the imaging quality of the optical lens through reasonable configuration of the surface type of each lens and reasonable matching of the focal power.

Description

TECHNICAL FIELD

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

[0002] With the continuous improvement of people's requirements for driving experience, vehicle application type optical lenses are used more and more in intelligent driving, and the position of vehicle optical lenses in the automobile industry is continuously improved.

[0003] The camera of the vehicle DMS system belongs to the imaging camera and is mainly applied to the cabin. Its main functions include driver fatigue detection, face recognition and other functions. The lens of the existing DMS system requires not only that the optical lens has a light and thin shape with a small front aperture and has characteristics such as high pixels and high resolution, but also that the optical lens can clearly image under low illumination conditions, so it is necessary to develop an optical lens with good imaging effect. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide an optical lens with excellent imaging quality.

[0005] The present application provides an optical lens, which has a total of six lenses, and the lenses are arranged in order along the optical axis from the object side to the imaging surface as follows:

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

[0007] The second lens has a positive focal power, and both the object side surface and the image side surface are convex surfaces;

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

[0009] The fourth lens has a negative focal power, and both the object side surface and the image side surface are concave surfaces;

[0010] The fifth lens has a positive focal power, and both the object side surface and the image side surface are convex surfaces;

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

[0012] The effective focal length f of the optical lens and the image side surface curvature radius R6 of the third lens satisfy: R6 / f>14.0.

[0013] Further preferably, the object side surface curvature radius R5 and the image side surface curvature radius R6 of the third lens satisfy: -1<(R5-R6) / (R5+R6)<0.

[0014] It is further preferred that an image-side sag height Sag6 of the third lens and an image-side half aperture radius d6 satisfy -0.12 < Sag6 / d6 < 0.

[0015] It is further preferred that an optical total track length TTL of the optical lens and an effective focal length f satisfy 3.0 < TTL / f < 5.5.

[0016] It is further preferred that an effective focal length f of the optical lens and a maximum field angle FOV and a real image height IH corresponding to the maximum field angle satisfy 0.5 < (IH / 2) / (f x tan(FOV / 2)) < 0.75.

[0017] It is further preferred that an effective focal length f of the optical lens and a real image height IH corresponding to the maximum field angle satisfy 1.5 < IH / f < 2.5.

[0018] It is further preferred that an effective focal length f of the optical lens and a focal length f1 of the first lens satisfy -1.7 < f1 / f < -1.0.

[0019] It is further preferred that an effective focal length f of the optical lens and a focal length f2 of the second lens satisfy 1.0 < f2 / f < 2.0.

[0020] It is further preferred that an effective focal length f of the optical lens and a focal length f3 of the third lens satisfy 2.0 < f3 / f < 2.8.

[0021] It is further preferred that an effective focal length f of the optical lens and a focal length f4 of the fourth lens satisfy -1.5 < f4 / f < -1.0.

[0022] The optical lens provided by the present application can effectively limit the length of the lens, is conducive to the miniaturization of the optical lens, and improves the resolving power of the optical lens, reduces aberration, and improves the imaging quality of the optical lens by reasonable configuration of the surface shape of each lens and reasonable matching of the focal power. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0024] Figure 1 FIG. 1 is a structure diagram of an optical lens according to an embodiment of the present application.

[0025] Figure 2 FIG. 2 is a field curvature curve of the optical lens according to the embodiment of the present application.

[0026] Figure 3 FIG. 3 is an F-Tanθ distortion curve of the optical lens according to the embodiment of the present application.

[0027] Figure 4 MTF curve of the optical lens in Embodiment 1 of the present application.

[0028] Figure 5 Relative illuminance curve of the optical lens in Embodiment 1 of the present application.

[0029] Figure 6 Axial aberration curve of the optical lens in Embodiment 1 of the present application.

[0030] Figure 7 Vignetting curve of the optical lens in Embodiment 1 of the present application.

[0031] Figure 8 Structure diagram of the optical lens in Embodiment 2 of the present application.

[0032] Figure 9 Curvature of field curve of the optical lens in Embodiment 2 of the present application.

[0033] Figure 10 F-Tanθ distortion curve of the optical lens in Embodiment 2 of the present application.

[0034] Figure 11 MTF curve of the optical lens in Embodiment 2 of the present application.

[0035] Figure 12 Relative illuminance curve of the optical lens in Embodiment 2 of the present application.

[0036] Figure 13 Axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0037] Figure 14 Vignetting curve of the optical lens in Embodiment 2 of the present application.

[0038] Figure 15 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0039] Figure 16 Curvature of field curve of the optical lens in Embodiment 3 of the present application.

[0040] Figure 17 F-Tanθ distortion curve of the optical lens in Embodiment 3 of the present application.

[0041] Figure 18 MTF curve of the optical lens in Embodiment 3 of the present application.

[0042] Figure 19 Relative illuminance curve of the optical lens in Embodiment 3 of the present application.

[0043] Figure 20An axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0044] Figure 21 A transverse chromatic aberration curve of the optical lens in Embodiment 3 of the present application.

[0045] Figure 22 A structure diagram of the optical lens in Embodiment 4 of the present application.

[0046] Figure 23 A field curvature curve of the optical lens in Embodiment 4 of the present application.

[0047] Figure 24 An F-Tanθ distortion curve of the optical lens in Embodiment 4 of the present application.

[0048] Figure 25 An MTF curve of the optical lens in Embodiment 4 of the present application.

[0049] Figure 26 A relative luminance curve of the optical lens in Embodiment 4 of the present application.

[0050] Figure 27 An axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0051] Figure 28 A transverse chromatic aberration curve of the optical lens in Embodiment 4 of the present application.

[0052] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0053] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be noted that these detailed descriptions are only descriptions of embodiments of the present application and are not intended in any way to limit the scope of the present application. 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.

[0054] It is to be noted that, in the present specification, the expressions first, second, third, and the like are used only to distinguish one feature from another feature, and do not represent any limitation on the features. Thus, the first lens discussed below can also be referred to as a second lens or a third lens without departing from the teachings of the present application.

[0055] 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 to scale.

[0056] In the present disclosure, the paraxial region refers to a region near the optical axis. If a 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 a 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 plane is referred to as the image side surface of the lens.

[0057] It should also be understood that the words “comprise”, “comprising”, “has”, “having”, “include”, “including” and / or “contain”, “containing” 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 describing the embodiments of the present application, the word “may” means “one or more embodiments of the present application”. Furthermore, the word “exemplary” is intended to mean an example or an illustration.

[0058] Unless otherwise defined, all terms (including technical and scientific terms) used herein 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.

[0059] 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 accompanying drawings and in conjunction with the embodiments.

[0060] The optical lens according to the embodiments of the present application comprises, in order from the object side to the image side along the optical axis, a first lens, a second lens, a diaphragm, a third lens, a fourth lens, a fifth lens, a sixth lens, and a filter.

[0061] In some embodiments, the first lens can have a negative refractive power, which is conducive to reducing the angle of incidence of the incident light, thereby effectively sharing the large field of view on the object side. The object side surface of the first lens is convex, and the image side surface is concave, which is conducive to collecting as much edge field of view light as possible into the rear optical lens, thereby realizing large-angle light collection.

[0062] In some embodiments, the second lens can have positive refractive power, which is conducive to converging light rays while reducing the refraction angle of the light rays, so that the light rays transition smoothly. The object side and the image side of the second lens are both convex, which balances various aberrations generated by the optical lens and improves the imaging quality of the optical lens.

[0063] In some embodiments, the third lens can have positive refractive power, which is conducive to further converging light rays while reducing the refraction angle of the light rays, so that the light rays transition smoothly. The object side of the third lens is convex, and the image side is concave, which can reduce the influence of spherical aberration and astigmatism generated by the third lens itself on the optical lens, and improve the imaging quality of the optical lens.

[0064] In some embodiments, the fourth lens can have negative refractive power, and both the object side and the image side thereof are concave, which is conducive to balancing various aberrations generated by the optical lens and improving the imaging quality of the optical lens.

[0065] In some embodiments, the fifth lens can have positive refractive power, which is conducive to improving the light converging ability of the optical lens. Both the object side and the image side of the fifth lens are convex, which can reduce spherical aberration and coma generated by the fifth lens itself, and improve the imaging quality of the optical lens.

[0066] In some embodiments, the sixth lens can have negative refractive power, which is conducive to increasing the imaging area of the optical lens and improving the imaging quality of the optical lens. The object side of the sixth lens is convex, and the image side is concave, which can optimize the chromatic aberration of the optical lens and improve the imaging quality of the optical lens.

[0067] In some embodiments, the effective focal length f of the optical lens and the image side curvature radius R6 of the third lens satisfy: R6 / f>14.0. By adjusting the curvature radius of the image side of the third lens, the face type of the image side of the third lens can be appropriately adjusted, the influence of spherical aberration and astigmatism generated by the third lens itself on the optical lens can be reduced, and the imaging quality of the optical lens can be improved.

[0068] In some embodiments, the object side curvature radius R5 and the image side curvature radius R6 of the third lens satisfy: -1<(R5-R6) / (R5+R6)<0. By adjusting the curvature radius of the object side and the image side of the third lens, the refraction degree of light passing through the lens can be moderated, the influence of aberration generated by the third lens on the optical lens can be reduced, and the imaging quality of the optical lens can be improved.

[0069] In some embodiments, the image side sagitta Sag6 and the image side half-diameter of the third lens satisfy: -0.12<Sag6 / d6<0. By adjusting the off-axis region face type of the image side of the third lens, various aberrations of the edge field of view of the optical lens can be effectively improved, and the imaging quality of the edge field of view of the optical lens can be improved.

[0070] In some embodiments, the optical total track length TTL of the optical lens and the effective focal length f satisfy: 3.0 < TTL / f < 5.5. Satisfying the above range can effectively limit the length of the lens, and achieve miniaturization of the optical lens.

[0071] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV, and the real image height IH corresponding to the maximum field of view satisfy: 0.5 < (IH / 2) / (f*tan(FOV / 2)) < 0.75. Satisfying the above range can help balance the size of the field of view and the size of the F-Tan theta distortion of the optical lens, and improve the imaging quality of the optical lens.

[0072] In some embodiments, the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field of view satisfy: 1.5 < IH / f < 2.5. Satisfying the above range can help balance the size of the field of view and the size of the F-Tan theta distortion of the optical lens, and improve the imaging quality of the optical lens.

[0073] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.7 < f1 / f < -1.0. Satisfying the above range can make the first lens have a smaller negative focal power, which is conducive to increasing the field of view of the optical lens, and makes the refraction angle of the incident light change more gently, avoids excessive refraction change to generate too much aberration, and improves the imaging quality of the optical lens.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.0 < f2 / f < 2.0. Satisfying the above range can make the second lens have an appropriate positive focal power, which is conducive to the convergence of light, makes the divergent light entering the system from the front smoothly enter the rear optical system, and makes the light trend more gentle, optimizes the aberration, and improves the resolution.

[0075] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.0 < f3 / f < 2.8. Satisfying the above range can make the third lens have an appropriate positive focal power, which can reduce the influence of the spherical aberration and the astigmatism generated by the third lens itself on the optical lens, and improve the imaging quality of the optical lens.

[0076] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -1.5 < f4 / f < -1.0. Satisfying the above range can make the fourth lens have an appropriate negative focal power, which is conducive to balancing various aberrations generated by the optical lens, and improves the imaging quality of the optical lens.

[0077] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.8 < f5 / f < 1.2. Satisfying the above range, the fifth lens can have appropriate positive refractive power, and the spherical aberration and coma generated by the fifth lens itself can be reduced, thereby improving the imaging quality of the optical lens.

[0078] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.5 < f6 / f < -1.3. Satisfying the above range, the sixth lens can have appropriate negative refractive power, which is conducive to increasing the imaging area of the optical lens, and the chromatic aberration of the optical lens can be optimized, thereby improving the imaging quality of the optical lens.

[0079] In some embodiments, the maximum field of view FOV of the optical lens satisfies: 95° < FOV < 135°. Satisfying the above range, the optical lens can have a large field of view.

[0080] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value FNO satisfy: 40° < FOV / FNO < 65°. Satisfying the above range, the field of view of the optical lens can be expanded, and the aperture of the optical lens can be increased, which is conducive to the optical lens to obtain more scene information, meet the demand of large range detection, and improve the problem that the relative luminance of the edge field of view decreases rapidly, thereby obtaining more scene information.

[0081] In some embodiments, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view satisfy: 2.0 < TTL / IH < 2.5. Satisfying the above range, the demand of image height and miniaturization of the optical lens can be effectively balanced.

[0082] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD satisfy: 3.5 < IH / EPD < 5.0. Satisfying the above range, the width of the light beam entering the optical lens can be increased, so that the brightness of the optical lens at the image plane is improved to avoid dark corners.

[0083] In some embodiments, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view and the clear aperture D1 of the object side surface of the first lens satisfy: 0.4 < D1 / IH / tan(FOV / 2) < 0.8. Satisfying the above range, the balance between the size of the optical lens and the field of view and the image plane can be ensured.

[0084] In order to make the system have better optical performance, a plurality of aspherical lenses are used in the lens, and the shape of each aspherical surface of the optical lens satisfies the following equation:

[0085]

[0086] wherein z is the distance of the curved surface to the vertex of the curved surface in the direction of the optical axis, h is the distance of the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the coefficient of the quadratic curved surface, and A, B, C, D, E, and F are the coefficients of the second-order, fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order curved surfaces, respectively.

[0087] 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 should be included in the protection scope of the application.

[0088] Embodiment 1

[0089] Please refer to Figure 1 , which is a structural schematic diagram of the optical lens provided in Embodiment 1 of the application. The optical lens comprises, along the optical axis from the object side to the imaging surface, a first lens L1, a second lens L2, a stop ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter G1.

[0090] The first lens L1 has a negative focal power, the object side S1 is a convex surface, and the image side S2 is a concave surface;

[0091] The second lens L2 has a positive focal power, and the object side S3 and the image side S4 are both convex surfaces;

[0092] The stop ST;

[0093] The third lens L3 has a positive focal power, the object side S5 is a convex surface, and the image side S6 is a concave surface;

[0094] The fourth lens L4 has a negative focal power, and the object side S7 and the image side S8 are both concave surfaces;

[0095] The fifth lens L5 has a positive focal power, and the object side S9 and the image side S10 are both convex surfaces;

[0096] The sixth lens L6 has a negative focal power, the object side S11 is a convex surface, and the image side S12 is a concave surface;

[0097] The object side S13 and the image side S14 of the filter G1 are both flat surfaces;

[0098] The imaging surface S15 is a flat surface.

[0099] The related parameters of each lens in the optical lens in Embodiment 1 are shown in Table 1-1.

[0100] Table 1-1

[0101]

[0102]

[0103] The surface profile parameters of the aspherical lens of the optical lens in Example 1 are shown in Table 1-2.

[0104] Table 1-2

[0105] Face number K A B C D E F S1 -6.35E-01 0.00E+00 -1.52E-02 -7.40E-04 7.55E-05 -8.02E-07 -1.60E-07 S2 -1.31E+00 0.00E+00 2.37E-02 -3.75E-03 -1.33E-04 -2.45E-05 5.41E-06 S3 -9.96E+00 0.00E+00 -8.52E-04 -8.97E-04 1.95E-04 -1.23E-04 1.50E-05 S4 4.07E+00 0.00E+00 -2.18E-03 2.32E-03 5.81E-03 -3.93E-03 8.29E-04 S5 4.22E+00 0.00E+00 -3.51E-02 9.23E-03 -4.20E-03 1.82E-03 -8.65E-04 S6 -9.24E+01 0.00E+00 -2.73E-03 -5.30E-02 3.89E-02 -1.50E-02 2.50E-03 S7 2.46E+01 0.00E+00 4.03E-03 -3.82E-02 2.66E-02 -1.14E-02 2.16E-03 S8 7.43E-01 0.00E+00 -4.13E-02 1.73E-02 -7.76E-03 1.61E-03 -1.17E-04 S9 4.25E-02 0.00E+00 -3.66E-02 8.91E-03 -2.85E-03 2.68E-04 -1.04E-05 S10 -5.95E+00 0.00E+00 -2.25E-02 1.79E-03 -3.24E-04 1.44E-05 -4.09E-06 S11 2.41E+00 0.00E+00 -5.03E-02 1.81E-03 -4.65E-04 1.52E-04 -1.83E-05 S12 -7.05E+00 0.00E+00 -2.19E-02 1.06E-04 3.21E-04 -5.21E-05 2.17E-06

[0106] In this embodiment, the field curvature curve, F-Tanθ distortion curve, MTF curve, relative illumination curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens are shown in FIGS. 1-1 to 1-6, respectively. Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7

[0107] Figure 2 The field curvature curve of Example 1 is shown, which represents the curvature of the meridional image surface and 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: °). As can be seen from the figure, the field curvature of the meridional image surface and the sagittal image surface is controlled within -0.09mm~0.1mm, which shows that the optical lens can well correct the field curvature.

[0108] Figure 3 The F-Tanθ distortion curve of Example 1 is shown, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Tanθ distortion (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Tanθ distortion of the optical lens is controlled within -40%~0, the image compression in the edge angle region is relatively flat, and the clarity of the expanded image is effectively improved.

[0109] Figure 4 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of the present embodiment is above 0.5 within the full field of view, and within the range of 0~160lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in both low frequency and high frequency cases.

[0110] Figure 5 ​The relative luminance curve of the embodiment 1 is shown, which represents the relative luminance values of different field angles on the imaging plane, the horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative luminance (unit: %). As can be seen from the figure, the relative luminance value of the optical lens is still greater than 70% at the maximum half field angle, which shows that the optical lens has good relative luminance.

[0111] Figure 6 The axial aberration curve of the embodiment 1 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging plane, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the shift of the axial aberration is controlled within -30 μm-40 μm, which shows that the optical lens can better correct the axial aberration.

[0112] Figure 7 The axial aberration curve of the embodiment 1 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging plane, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the shift of the axial aberration is controlled within -30 μm-40 μm, which shows that the optical lens can better correct the axial aberration.

[0113] Embodiment 2

[0114] Please refer to Figure 8 , which is a structural schematic diagram of the optical lens provided in the embodiment 2 of the present application. Compared with the embodiment 1, the main difference is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0115] The related parameters of each lens in the optical lens in the embodiment 2 are shown in Table 2-1.

[0116] Table 2-1

[0117]

[0118]

[0119] The surface type parameters of the aspheric lens of the optical lens in the embodiment 2 are shown in Table 2-2.

[0120] Table 2-2

[0121] Face number K A B C D E F S1 -6.37E-01 0.00E+00 -1.52E-02 -7.44E-04 7.48E-05 -8.31E-07 -1.67E-07 S2 -1.33E+00 0.00E+00 2.30E-02 -3.82E-03 -1.14E-04 -2.19E-05 3.51E-06 S3 -9.80E+00 0.00E+00 -8.09E-04 -8.14E-04 2.05E-04 -1.25E-04 1.47E-05 S4 4.21E+00 0.00E+00 -2.35E-03 2.35E-03 5.76E-03 -3.85E-03 8.00E-04 S5 4.20E+00 0.00E+00 -3.38E-02 9.36E-03 -4.06E-03 1.94E-03 -7.74E-04 S6 9.99E+01 0.00E+00 -2.41E-03 -5.19E-02 3.93E-02 -1.50E-02 2.50E-03 S7 1.80E+01 0.00E+00 4.88E-03 -3.78E-02 2.67E-02 -1.14E-02 2.09E-03 S8 8.06E-01 0.00E+00 -4.05E-02 1.73E-02 -7.80E-03 1.56E-03 -1.09E-04 S9 -7.07E-03 0.00E+00 -3.71E-02 9.48E-03 -2.93E-03 2.35E-04 6.09E-06 S10 -6.17E+00 0.00E+00 -2.27E-02 1.71E-03 -3.39E-04 1.42E-05 -2.66E-06 S11 2.51E+00 0.00E+00 -5.02E-02 1.78E-03 -4.76E-04 1.50E-04 -1.78E-05 S12 -7.30E+00 0.00E+00 -2.21E-02 1.17E-04 3.24E-04 -5.17E-05 2.11E-06

[0122] In this embodiment, the field curvature curve, the F-Tanθ distortion curve, the MTF curve, the relative luminance curve, the axial aberration curve and the axial aberration curve of the optical lens are respectively as shown in Figure 9 , Figure 10、 Figure 11 、 Figure 12 、 Figure 13 、 Figure 14 as shown.

[0123] Figure 9 The field curvature curve of the embodiment 2 is shown, which represents the curvature of light rays of different wavelengths on the meridional image surface and sagittal image surface, 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 -0.09mm~0.1mm, which shows that the optical lens can well correct the field curvature.

[0124] Figure 10 The F-Tanθ distortion curve of the embodiment 2 is shown, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Tanθ distortion (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within -30%~0, the image compression in the edge angle region is relatively flat, and the clarity of the expanded image is effectively improved.

[0125] Figure 11 The MTF (Modulation Transfer Function) curve of the embodiment 2 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under 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 the embodiment is above 0.4 within the full field of view, and within the range of 0~160lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in low frequency and high frequency conditions.

[0126] Figure 12 The relative illumination curve of the embodiment 2 is shown, which represents the relative illumination value of different field angles on the imaging surface, the horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 70% at the maximum half field angle, which shows that the optical lens has good relative illumination.

[0127] Figure 13 The axial aberration curve of the embodiment 2 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: μm), 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 -30μm~15μm, which shows that the optical lens can well correct the axial aberration.

[0128] Figure 14The vertical color aberration curve of embodiment 2 is shown, which represents the color aberration of each wavelength at different image heights on the imaging plane relative to the central wavelength (0.55 μm), the horizontal axis represents the vertical color aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. As can be seen from the figure, the vertical color aberration of the longest wavelength and the shortest wavelength is controlled within -2 μm ~ 8 μm, which shows that the optical lens can well correct the color aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0129] Embodiment 3

[0130] Referring to Figure 15 , a structural schematic diagram of the optical lens provided in embodiment 3 of the present application is shown, and compared with embodiment 1, the main difference is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0131] The related parameters of each lens in the optical lens in embodiment 3 are shown in Table 3-1.

[0132] Table 3-1

[0133]

[0134]

[0135] The surface type parameters of the aspherical lens of the optical lens in embodiment 3 are shown in Table 3-2.

[0136] Table 3-2

[0137] Face number K A B C D E F S1 -6.40E-01 0.00E+00 -1.53E-02 -7.49E-04 7.50E-05 -7.96E-07 -1.61E-07 S2 -1.31E+00 0.00E+00 2.31E-02 -3.83E-03 -1.10E-04 -1.62E-05 3.16E-06 S3 1.55E+01 0.00E+00 -4.74E-04 -8.94E-04 2.45E-04 -1.23E-04 1.38E-05 S4 3.87E+00 0.00E+00 -2.27E-03 4.43E-03 4.59E-03 -4.65E-03 1.27E-03 S5 4.38E+00 0.00E+00 -2.95E-02 4.98E-03 -3.43E-03 2.27E-03 -9.31E-04 S6 2.57E+01 0.00E+00 -4.39E-03 -4.97E-02 3.87E-02 -1.48E-02 2.68E-03 S7 1.01E+01 0.00E+00 5.65E-03 -3.81E-02 2.78E-02 -1.14E-02 2.10E-03 S8 8.23E-01 0.00E+00 -3.96E-02 1.79E-02 -7.73E-03 1.54E-03 -1.34E-04 S9 1.29E-01 0.00E+00 -3.69E-02 1.00E-02 -2.84E-03 2.60E-04 3.43E-06 S10 -5.42E+00 0.00E+00 -2.25E-02 1.61E-03 -3.63E-04 1.40E-05 -1.76E-06 S11 2.40E+00 0.00E+00 -4.98E-02 1.79E-03 -4.66E-04 1.50E-04 -1.72E-05 S12 -7.04E+00 0.00E+00 -2.21E-02 1.22E-04 3.26E-04 -5.15E-05 2.00E-06

[0138] In this embodiment, the field curvature curve, F-Tanθ distortion curve, MTF curve, relative luminance curve, axial aberration curve, and vertical color aberration curve of the optical lens are shown in Figure 16 、 Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 、 Figure 21 respectively.

[0139] Figure 16 The field curvature curve of embodiment 3 is shown, which represents the bending degree of light rays of different wavelengths on the meridional image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.03 mm ~ 0.09 mm, which shows that the optical lens can well correct the field curvature.

[0140] Figure 17The F-Tanθ distortion curve of the embodiment 3 is shown, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging plane, the horizontal axis represents the F-Tanθ distortion (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Tanθ distortion of the optical lens is controlled within-50%~0, the image compression in the edge angle region is relatively gentle, and the clarity of the expanded image is effectively improved.

[0141] Figure 18 The MTF (Modulation Transfer Function) curve of the embodiment 3 is shown, which represents the lens imaging modulation degree of different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of the embodiment is above 0.5 in the full field of view, and in the range of 0~160 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0142] Figure 19 The relative illumination curve of the embodiment 3 is shown, which represents the relative illumination value of different field angles on the imaging plane, the horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 70% at the maximum half field angle, which indicates that the optical lens has good relative illumination.

[0143] Figure 20 The axial aberration curve of the embodiment 3 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging plane, the horizontal axis represents the axial aberration value (unit: μm), 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-15 μm~45 μm, which indicates that the optical lens can better correct the axial aberration.

[0144] Figure 21 The sagittal chromatic aberration curve of the embodiment 3 is shown, which represents the chromatic aberration of each wavelength at different image heights on the imaging plane relative to the center wavelength (0.55 μm), the horizontal axis represents the sagittal chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field angle. As can be seen from the figure, the sagittal chromatic aberration of the longest wavelength and the shortest wavelength is controlled within-2 μm~10 μm, which indicates that the optical lens can very well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0145] Embodiment 4

[0146] Please refer to Figure 22 , which is a structural schematic diagram of the optical lens provided in the embodiment 4 of the present application. Compared with the embodiment 1, the main difference of the embodiment is that the curvature radius, lens thickness and other optical parameters of each lens surface are different.

[0147] The related parameters of each lens in the optical lens in embodiment 4 are shown in table 4-1.

[0148] Table 4-1

[0149]

[0150]

[0151] The surface type parameters of the aspherical lens of the optical lens in embodiment 4 are shown in table 4-2.

[0152] Table 4-2

[0153] Face number K A B C D E F S1 -1.10E+00 0.00E+00 -1.88E-02 -7.26E-04 1.79E-04 2.18E-06 -1.01E-06 S2 -1.48E+00 0.00E+00 1.66E-02 -4.86E-03 -4.30E-04 2.37E-05 1.42E-05 S3 3.18E+01 0.00E+00 3.96E-03 -2.14E-03 6.78E-04 -3.48E-04 3.00E-05 S4 3.77E+00 0.00E+00 -8.47E-04 4.29E-03 6.75E-04 -1.42E-03 3.78E-04 S5 4.04E+00 0.00E+00 -2.35E-02 3.67E-03 -3.86E-03 1.68E-03 -6.02E-04 S6 -1.00E+02 0.00E+00 -5.27E-03 -4.80E-02 3.71E-02 -1.48E-02 2.40E-03 S7 -2.96E+00 0.00E+00 7.30E-03 -3.67E-02 2.85E-02 -1.20E-02 2.00E-03 S8 7.67E-01 0.00E+00 -3.91E-02 1.88E-02 -7.12E-03 1.50E-03 -1.19E-04 S9 -9.58E-01 0.00E+00 -3.92E-02 1.10E-02 -3.07E-03 2.40E-04 5.77E-05 S10 -5.90E+00 0.00E+00 -1.89E-02 1.42E-03 -3.34E-04 2.19E-05 -9.26E-08 S11 2.20E+00 0.00E+00 -4.88E-02 1.98E-03 -4.66E-04 1.43E-04 -1.25E-05 S12 -6.29E+00 0.00E+00 -2.16E-02 1.65E-04 3.28E-04 -4.18E-05 1.53E-06

[0154] In this embodiment, the field curvature curve, F-Tanθ distortion curve, MTF curve, relative illumination curve, axial aberration curve and transverse chromatic aberration curve of the optical lens are shown in FIGS. 4-1 to 4-6 respectively. Figure 23 、 Figure 24 、 Figure 25 、 Figure 26 、 Figure 27 、 Figure 28

[0155] Figure 23 The field curvature curve of embodiment 4 is shown, which represents the curvature degree of light rays of different wavelengths on the meridional image surface and sagittal image surface, 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-0.03mm~0.12mm, which shows that the optical lens can well correct the field curvature.

[0156] Figure 24 The F-Tanθ distortion curve of embodiment 4 is shown, which represents the F-Tanθ distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Tanθ distortion (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Tanθ distortion of the optical lens is controlled within-30%~0, the image compression in the edge angle region is relatively flat, and the clarity of the expanded image is effectively improved.

[0157] Figure 25 ​The MTF (Modulation Transfer Function) curve of the embodiment 4 is shown, which represents the lens imaging modulation degree of different spatial frequencies under 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 the embodiment is above 0.5 in the full field of view, and in the range of 0-160 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0158] Figure 26 The relative illumination curve of the embodiment 4 is shown, which represents the relative illumination value of different field angles on the imaging surface, the horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 70% at the maximum half field angle, which shows that the optical lens has good relative illumination.

[0159] Figure 27 The axial aberration curve of the embodiment 4 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the shift amount of the axial aberration is controlled within-15 μm-50 μm, which shows that the optical lens can better correct the axial aberration.

[0160] Figure 28 The axial aberration curve of the embodiment 4 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the shift amount of the axial aberration is controlled within-15 μm-50 μm, which shows that the optical lens can better correct the axial aberration.

[0161] Please refer to Table 5, the optical properties corresponding to each of the above embodiments, including the effective focal length f, the total optical length TTL, the aperture value FNO, the real image height IH and the maximum field of view FOV of the optical lens, and the numerical value corresponding to each conditional expression in each embodiment.

[0162] Table 5

[0163]

[0164]

[0165] In summary, the optical lens provided by the present application can effectively limit the length of the lens, which is conducive to the miniaturization of the optical lens, and through the reasonable configuration of the surface shape of each lens and the reasonable matching of the optical power, the resolving power of the optical lens is improved, the aberration is reduced, and the imaging quality of the optical lens is improved.

[0166] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like 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.

[0167] The above-described embodiments only express several implementation manners of the present application, which are described in a more specific and detailed manner, but cannot be understood as the limitation of the patent scope of the present application. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, 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 plane along the optical axis: a first lens with negative refractive power, whose object side surface is a convex surface and whose image side surface is a concave surface; a second lens with positive refractive power, both of whose object side surface and image side surface are convex surfaces; a third lens with positive refractive power, whose object side surface is a convex surface and whose image side surface is a concave surface; a fourth lens with negative refractive power, both of whose object side surface and image side surface are concave surfaces; a fifth lens with positive refractive power, both of whose object side surface and image side surface are convex surfaces; a sixth lens with negative refractive power, whose object side surface is a convex surface and whose image side surface is a concave surface; The effective focal length f of the optical lens and the image side surface curvature radius R6 of the third lens satisfy: 18.72≥R6 / f>14.0; The object side surface curvature radius R5 and the image side surface curvature radius R6 of the third lens satisfy: -1<(R5-R6) / (R5+R6)≤-0.86; The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.0<f3 / f<2.

8.

2. 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: 0.8<f5 / f<1.

2.

3. The optical lens of claim 1, wherein, The image side surface sagitta Sag6 and the image side surface half-diameter of light d6 of the third lens satisfy: -0.12<Sag6 / d6<0.

4. The optical lens of claim 1, wherein, The total optical length TTL and the effective focal length f of the optical lens satisfy: 3.0<TTL / f<5.

5.

5. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the maximum field of view angle FOV and the real image height IH corresponding to the maximum field of view angle satisfy: 0.5<(IH / 2) / (fxtan(FOV / 2))<0.

75.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the real image height IH corresponding to the maximum field of view angle satisfy: 1.5<IH / f<2.

5.

7. 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: -1.7<f1 / f<-1.

0.

8. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.0<f2 / f<2.

0.

9. 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: -2.5<f6 / f<-1.

3.

10. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -1.5<f4 / f<-1.0.

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