Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses in sequence along an optical axis from an object side to an imaging surface, and the seven lenses comprise: a first lens with negative optical power, wherein the object side surface is a convex surface and the image side surface is a concave surface; a second lens with negative optical power, wherein the object side surface is a convex surface and the image side surface is a concave surface; a third lens with positive optical power, wherein the object side surface is a concave surface and the image side surface is a convex surface; a fourth lens with positive optical power, wherein the object side surface and the image side surface are both convex surfaces; a fifth lens with positive optical power, wherein the object side surface and the image side surface are both convex surfaces; a sixth lens with negative optical power, wherein the object side surface and the image side surface are both concave surfaces; and a seventh lens with positive optical power, wherein the object side surface and the image side surface are both convex surfaces. The optical lens provided by the application improves the imaging quality of the optical lens, reduces aberration and improves the imaging quality of the optical lens through reasonable configuration of the surface shape of each lens and reasonable matching of optical 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] Advanced Driver Assistance System (ADAS) plays an important role in intelligent driving, which collects environmental information through various lenses combined with sensors to ensure the safety of drivers. Some lenses of the existing ADAS system adopt wide-angle lenses, which have large aberration, large field curvature, poor imaging quality and other problems, and are difficult to meet the needs of users. Therefore, 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 the advantages of excellent imaging quality.

[0005] The present application provides an optical lens, which comprises seven lenses in sequence along the optical axis from the object side to the imaging surface:

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

[0007] The second lens with negative focal power has a convex object side surface and a concave image side surface;

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

[0009] The fourth lens with positive focal power has a convex object side surface and a convex image side surface;

[0010] The fifth lens with positive focal power has a convex object side surface and a convex image side surface;

[0011] The sixth lens with negative focal power has a concave object side surface and a concave image side surface;

[0012] The seventh lens with positive focal power has a convex object side surface and a convex image side surface;

[0013] The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: f3 / f>100.

[0014] Further preferably, the maximum field of view FOV of the optical lens and the aperture value FNO satisfy: 80°<FOV / FNO<105°.

[0015] It is further preferred that the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -4.8 < f1 / f < -3.2.

[0016] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0017] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0018] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0019] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0020] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0021] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0022] It is further preferred that the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5.

[0023] The optical lens provided by the present application improves the imaging quality of the optical lens, reduces aberration, and improves the imaging quality of the optical lens by reasonable configuration of each lens surface and reasonable matching of optical power. BRIEF DESCRIPTION OF DRAWINGS

[0024] 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:

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

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

[0027] Figure 3 F-Theta distortion curve of the optical lens in Embodiment 1 of the present application.

[0028] Figure 4 Relative illumination curve of the optical lens in Embodiment 1 of the present application.

[0029] Figure 5 MTF curve of the optical lens in Embodiment 1 of the present application.

[0030] Figure 6 Axial aberration curve of the optical lens in Embodiment 1 of the present application.

[0031] Figure 7 Vignetting curve of the optical lens in Embodiment 1 of the present application.

[0032] Figure 8 Structure diagram of the optical lens in Embodiment 2 of the present application.

[0033] Figure 9 Curvature of field curve of the optical lens in Embodiment 2 of the present application.

[0034] Figure 10 F-Theta distortion curve of the optical lens in Embodiment 2 of the present application.

[0035] Figure 11 Relative illumination curve of the optical lens in Embodiment 2 of the present application.

[0036] Figure 12 MTF curve of the optical lens in Embodiment 2 of the present application.

[0037] Figure 13 Axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0038] Figure 14 Vignetting curve of the optical lens in Embodiment 2 of the present application.

[0039] Figure 15 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0040] Figure 16 Curvature of field curve of the optical lens in Embodiment 3 of the present application.

[0041] Figure 17 F-Theta distortion curve of the optical lens in Embodiment 3 of the present application.

[0042] Figure 18 Relative illumination curve of the optical lens in Embodiment 3 of the present application.

[0043] Figure 19MTF curve of the optical lens in Embodiment 3 of the present application.

[0044] Figure 20 Axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0045] Figure 21 Vignetting curve of the optical lens in Embodiment 3 of the present application.

[0046] Figure 22 Structure diagram of the optical lens in Embodiment 4 of the present application.

[0047] Figure 23 Field curve of the optical lens in Embodiment 4 of the present application.

[0048] Figure 24 F-Theta distortion curve of the optical lens in Embodiment 4 of the present application.

[0049] Figure 25 Relative illumination curve of the optical lens in Embodiment 4 of the present application.

[0050] Figure 26 MTF curve of the optical lens in Embodiment 4 of the present application.

[0051] Figure 27 Axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0052] Figure 28 Vignetting curve of the optical lens in Embodiment 4 of the present application.

[0053] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0054] 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 description, 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.

[0055] It should be noted that, in the present specification, the expressions first, second, third, etc. are merely used to distinguish one feature from another feature, 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.

[0056] In the drawings, the thickness, size, and shape of the lenses have been exaggerated slightly for ease of explanation. Specifically, the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0057] In this document, 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 surface is referred to as the image side surface of the lens.

[0058] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", when used in this specification, mean that something is included, but do not exclude the presence of one or more additional features, elements, components, and / or combinations thereof. In addition, when describing the embodiments of the present application, the use of "may" means that one or more embodiments of the present application. Also, the word "exemplary" is intended to mean an example or an illustration.

[0059] 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.

[0060] 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.

[0061] The optical lens of the embodiment of the present application comprises, in order from the object side to the imaging surface along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, a filter, and a protective glass.

[0062] In some embodiments, the first lens can have a negative focal power, a convex object side surface, and a concave image side surface. The second lens can have a negative focal power, a convex object side surface, and a concave image side surface. The third lens can have a positive focal power, a concave object side surface, and a convex image side surface. The fourth lens can have a positive focal power, both the object side surface and the image side surface being convex. The fifth lens can have a positive focal power, both the object side surface and the image side surface being convex. The sixth lens can have a negative focal power, both the object side surface and the image side surface being concave. The seventh lens can have a positive focal power, both the object side surface and the image side surface being convex.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: f3 / f > 100. Satisfying the above range is conducive to improving the light convergence capability of the optical lens, correcting the astigmatism and field curvature introduced by the front end of the lens, reducing the light deflection angle, making the light trend transition smoothly, and improving the imaging quality of the optical lens.

[0064] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f satisfy: 8.0 < TTL / f < 11.0. Satisfying the above range ensures sufficient space to adjust the lens structure and optimize the imaging effect.

[0065] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value FNO satisfy: 80° < FOV / FNO < 105°. Satisfying the above range is conducive to balancing the relationship between the field of view and the aperture.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -4.8 < f1 / f < -3.2. Satisfying the above range can make the first lens have appropriate negative focal power, which is conducive to reducing the inclination angle of the incident light and collecting as much edge field of view light as possible into the rear optical lens, realizing large-angle light collection.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.9 < f2 / f < -3.5. Satisfying the above range can make the second lens have appropriate negative focal power, which can share the negative focal power of the front end of the lens, thereby reducing the excessive light deflection caused by the excessive concentration of the focal power of the first lens, reducing the difficulty of chromatic aberration correction of the optical lens, and improving the imaging quality of the optical lens.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.0 < f4 / f < 3.5. Satisfying the above range can make the fourth lens have appropriate positive focal power, which is conducive to improving the light convergence capability of the optical lens and balancing various aberrations generated by the optical lens, thereby improving the imaging quality of the optical lens.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.0 < f5 / f < 1.5. Satisfying the above range can make the fifth lens have appropriate positive refractive power, which is conducive to improving the light convergence capability of the optical lens, while balancing the aberration of the optical lens and improving the imaging quality of the optical lens.

[0070] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -1.5 < f6 / f < -0.5. Satisfying the above range can make the sixth lens have appropriate negative refractive power, which is conducive to improving the relative illumination.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.5 < f7 / f < 3.5. Satisfying the above range can make the seventh lens have appropriate positive refractive power, which is conducive to suppressing the angle of the edge field of view incident on the imaging surface, effectively transmitting more light beams to the imaging surface, and improving the imaging quality of the optical lens.

[0072] In some embodiments, the object side surface radius of curvature R13 of the seventh lens and the image side surface radius of curvature R14 of the seventh lens satisfy: -1.7 < (R13-R14) / (R13+R14) < -1.0. Satisfying the above range can reduce the deviation of the incident angle and the exit angle of light rays of different fields of view, make the light rays transition smoothly, thereby reducing the tolerance sensitivity, and be conducive to improving the yield of the optical lens.

[0073] In some embodiments, the effective focal length f of the optical lens and the combined focal length f56 of the fifth lens and the sixth lens satisfy: -8.0 < f56 / f < -5.5. Satisfying the above range, by matching the two lenses with positive and negative refractive powers, the aberrations generated by each other can be offset, and by setting the positive and negative lenses in the cemented lens and the combined focal length of the positive and negative lens groups, the chromatic aberration of the optical imaging system can be effectively corrected, thereby improving the resolving power of the system.

[0074] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f34 of the third lens and the fourth lens satisfy: -0.9 < f12 / f34 < -0.75. Satisfying the above range is conducive to expanding the width of the light beam, so that the large-angle light rays entering can be fully transmitted to the rear optical system after the third lens and the fourth lens, so as to obtain a wider field of view range and higher relative illumination.

[0075] In some embodiments, the object side surface aperture D1 of the first lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV satisfy: -0.5 < D1 / IH / tan(FOV / 2) < -0.2. Satisfying the above range can balance the relationship between the working aperture of the first lens and the image size and the field of view angle.

[0076] In some embodiments, the refractive index Nd5 of the fifth lens and the refractive index Nd6 of the sixth lens satisfy: |Nd5-Nd6|>0.1. The Abbe number Vd5 of the fifth lens and the Abbe number Vd6 of the sixth lens satisfy: |Vd5-Vd6|>30. By satisfying the above ranges, the refractive index and the dispersion coefficient of the two lenses are optimally matched, which can effectively correct the chromatic aberration of the optical imaging system, thereby improving the resolving power of the system, and also facilitates the athermalization design of the lens.

[0077] In some embodiments, the central thickness CT3 of the third lens along the optical axis and the central thickness CT4 of the fourth lens along the optical axis satisfy: 1.0<CT3 / CT4<1.8. By satisfying the above range, the thickness sensitivity of the optical lens can be reduced, and the field curvature and distortion of the optical lens can be effectively corrected, thereby enabling the optical lens to obtain good image quality in the full field of view.

[0078] In some embodiments, the fifth lens and the sixth lens can be cemented to form a cemented lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; and can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0079] 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:

[0080]

[0081] wherein z is the distance of the curved surface from the vertex of the curved surface in the direction of the optical axis, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic surface coefficient, and A, B, C, D, E, and F are the second-order, fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order curved surface coefficients, respectively.

[0082] 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 only preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, and any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the application should be regarded as equivalent replacement methods, and are included in the protection scope of the application.

[0083] Embodiment 1

[0084] Please refer to Figure 1Figure 1 shows a structural schematic diagram of an optical lens provided in Embodiment 1 of the present application, which comprises, along an optical axis from an object side to an imaging surface, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1 and a protective glass G2.

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

[0086] The second lens L2 has a negative focal power, and its object side S3 is a convex surface and its image side S4 is a concave surface.

[0087] The third lens L3 has a positive focal power, and its object side S5 is a concave surface and its image side S6 is a convex surface.

[0088] The fourth lens L4 has a positive focal power, and its object side S7 and its image side S8 are both convex surfaces.

[0089] The stop ST.

[0090] The fifth lens L5 has a positive focal power, and its object side S9 and its image side S10 are both convex surfaces.

[0091] The sixth lens L6 has a negative focal power, and its object side S10 and its image side S11 are both concave surfaces.

[0092] The fifth lens L5 and the sixth lens L6 form a cemented lens group, and the cemented surface S10 is formed by the image side of the fifth lens L5 and the object side of the sixth lens L6.

[0093] The seventh lens L7 has a positive focal power, and its object side S12 and its image side S13 are both convex surfaces.

[0094] The object side S14 and the image side S15 of the filter G1 are both flat surfaces.

[0095] The object side S16 and the image side S17 of the protective glass G2 are both flat surfaces.

[0096] The imaging surface S18 is a flat surface.

[0097] The related parameters of the lenses in the optical lens in Embodiment 1 are shown in Table 1-1.

[0098] Table 1-1

[0099]

[0100]

[0101] The surface type parameters of the aspheric lenses in the optical lens in Embodiment 1 are shown in Table 1-2.

[0102] Table 1-2

[0103] Face number K A B C D E F S3 -6.79E-01 0.00E+00 -3.13E-03 1.04E-04 -2.04E-06 2.09E-08 -8.79E-11 S4 -4.40E+00 0.00E+00 -6.58E-04 3.49E-05 4.97E-07 -3.19E-08 3.26E-10 S7 -2.68E-01 0.00E+00 -4.39E-05 -1.25E-06 3.80E-08 -5.77E-10 -1.07E-10 S8 -9.57E+00 0.00E+00 1.25E-04 2.84E-06 -3.66E-07 -3.08E-09 1.91E-10 S12 -1.22E+00 0.00E+00 -7.60E-04 6.45E-05 -5.53E-06 2.45E-07 -5.55E-09 S13 6.53E+01 0.00E+00 -6.94E-04 5.25E-05 -3.23E-06 1.06E-07 -2.28E-09

[0104] In this embodiment, the field curvature curve, F-Theta distortion curve, relative illumination curve, MTF curve, axial aberration curve, and transverse aberration curve of the optical lens are shown in FIGS. 1-1 to 1-5, respectively. Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7

[0105] Figure 2 The field curvature curve of Example 1 is shown, which represents the curvature of 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 -0.04 mm to 0.02 mm, which indicates that the optical lens can well correct the field curvature.

[0106] Figure 3 The F-Theta distortion curve of Example 1 is shown, which represents the F-Theta distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within -30% to 0, the image compression in the edge angle region is relatively flat, and the clarity of the expanded image is effectively improved.

[0107] Figure 4 The relative illumination curve of Example 1 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: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 80% at the maximum half field angle, which indicates that the optical lens has good relative illumination.

[0108] Figure 5 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 this embodiment is above 0.5 within the full field of view, and within the range of 0-160 lp / 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 both low and high frequency cases.

[0109] Figure 6 ​The axial aberration curve of the optical lens provided in Embodiment 1 is shown in FIG. 1, which represents the 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 -12 μm ~ 18 μm, which indicates that the optical lens can correct the axial aberration well.

[0110] Figure 7 The axial aberration curve of the optical lens provided in Embodiment 1 is shown in FIG. 1, which represents the 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 -12 μm ~ 18 μm, which indicates that the optical lens can correct the axial aberration well.

[0111] Embodiment 2

[0112] Please refer to Figure 8 , which is a structural schematic view of the optical lens provided in Embodiment 2 of the present application. Compared with Embodiment 1, the main difference between the two embodiments is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0113] The related parameters of each lens in the optical lens in Embodiment 2 are shown in Table 2-1.

[0114] Table 2-1

[0115]

[0116]

[0117] The surface type parameters of the aspherical lens of the optical lens in Embodiment 2 are shown in Table 2-2.

[0118] Table 2-2

[0119] Face number K A B C D E F S3 -6.72E-01 0.00E+00 -3.10E-03 1.03E-04 -2.02E-06 2.08E-08 -8.98E-11 S4 -4.05E+00 0.00E+00 -5.90E-04 3.67E-05 5.33E-07 -3.10E-08 3.16E-10 S7 -2.93E-01 0.00E+00 -6.01E-05 -2.25E-07 -2.72E-08 8.12E-10 -7.95E-11 S8 7.17E+00 0.00E+00 1.22E-04 1.36E-06 -3.98E-07 4.17E-09 3.63E-11 S12 -7.94E-01 0.00E+00 -6.96E-04 6.61E-05 -5.56E-06 2.52E-07 -5.80E-09 S13 6.46E+01 0.00E+00 -7.06E-04 5.63E-05 -3.21E-06 9.44E-08 -2.29E-09

[0120] In this embodiment, the field curvature curve, the F-Theta distortion curve, the relative luminance curve, the MTF curve, the axial aberration curve and the axial aberration curve of the optical lens are shown in FIGS. Figure 9 、 Figure 10 、 Figure 11 、 Figure 12 、 Figure 13 、 Figure 14

[0121] Figure 9 ​The field curvature curve of embodiment 2 is shown, which represents the curvature of light rays of different wavelengths on the meridional image surface and the sagittal image surface, 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 -0.03mm~0.02mm, which shows that the optical lens can well correct the field curvature.

[0122] Figure 10 The F-Theta distortion curve of embodiment 2 is shown, which represents the F-Theta distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta 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.

[0123] Figure 11 The relative luminance curve of embodiment 2 is shown, which represents the relative luminance 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 luminance (unit: %). As can be seen from the figure, the relative luminance value of the optical lens is still greater than 85% at the maximum half field angle, which shows that the optical lens has good relative luminance.

[0124] Figure 12 The MTF (Modulation Transfer Function) curve of 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. As can be seen from the figure, the MTF value of the embodiment is above 0.4 in the full field of view, and in 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.

[0125] Figure 13 The axial aberration curve of 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. As can be seen from the figure, the offset of the axial aberration is controlled within -12μm~10μm, which shows that the optical lens can well correct the axial aberration.

[0126] 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 surface 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 ±1 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 surface.

[0127] Embodiment 3

[0128] Please refer to Figure 15 , which is a structural schematic diagram of the optical lens provided in embodiment 3 of the present application. Compared with embodiment 1, the main difference of the present embodiment is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0129] The related parameters of each lens in the optical lens in embodiment 3 are shown in Table 3-1.

[0130] Table 3-1

[0131]

[0132]

[0133] The surface type parameters of the aspherical lens of the optical lens in embodiment 3 are shown in Table 3-2.

[0134] Table 3-2

[0135] Face number K A B C D E F S3 -6.82E-01 0.00E+00 -3.10E-03 1.03E-04 -2.02E-06 2.08E-08 -8.97E-11 S4 -3.99E+00 0.00E+00 -5.66E-04 3.71E-05 5.46E-07 -3.06E-08 3.27E-10 S7 -2.85E-01 0.00E+00 -6.35E-05 7.02E-07 -4.91E-08 1.30E-09 -3.87E-11 S8 5.50E+00 0.00E+00 1.23E-04 2.12E-06 -2.97E-07 5.66E-09 -4.40E-11 S12 -6.55E-01 0.00E+00 -6.59E-04 6.55E-05 -5.50E-06 2.46E-07 -5.07E-09 S13 1.50E+02 0.00E+00 -7.49E-04 5.98E-05 -3.18E-06 8.70E-08 -1.74E-09

[0136] In the present embodiment, the field curvature curve, the F-Theta distortion curve, the relative luminance curve, the MTF curve, the axial aberration curve, and the vertical color aberration curve of the optical lens are shown in Figure 16 、 Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 、 Figure 21 respectively.

[0137] 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 surface and the sagittal image surface, 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 -0.04 mm-0.02 mm, which shows that the optical lens can well correct the field curvature.

[0138] Figure 17The F-Theta distortion curve of the embodiment 3 is shown, which represents the F-Theta distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within-30%~0, the image compression in the edge angle region is relatively gentle, and the clarity of the expanded image is effectively improved.

[0139] Figure 18 The relative illumination curve of the embodiment 3 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: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 80% at the maximum half field angle, which indicates that the optical lens has good relative illumination.

[0140] Figure 19 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 0.4 within 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 low and high frequency conditions.

[0141] Figure 20 The axial aberration curve of the embodiment 3 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. As can be seen from the figure, the offset of the axial aberration is controlled within-12 μm~8 μm, which indicates that the optical lens can better correct the axial aberration.

[0142] 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 surface 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 ±1 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 surface.

[0143] Embodiment 4

[0144] Please refer to Figure 22 , which is a structural schematic diagram of the optical lens provided in the embodiment 4 of the present application, and compared with the embodiment 1, the main difference is that the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0145] The related parameters of each lens in the optical lens in embodiment 4 are shown in table 4-1.

[0146] Table 4-1

[0147]

[0148]

[0149] The surface type parameters of the aspherical lens of the optical lens in embodiment 4 are shown in table 4-2.

[0150] Table 4-2

[0151] Face number K A B C D E F S3 -6.63E-01 0.00E+00 -3.13E-03 1.02E-04 -1.99E-06 2.08E-08 -9.23E-11 S4 -3.82E+00 0.00E+00 -5.67E-04 3.65E-05 5.13E-07 -3.07E-08 3.22E-10 S7 -2.99E-01 0.00E+00 -6.44E-05 3.28E-07 -5.26E-08 1.11E-09 -5.77E-11 S8 4.30E+01 0.00E+00 1.09E-04 7.17E-07 -3.55E-07 4.91E-09 8.59E-12 S12 -7.61E-01 0.00E+00 -7.16E-04 6.72E-05 -5.39E-06 2.41E-07 -5.44E-09 S13 1.50E+02 0.00E+00 -7.77E-04 6.29E-05 -3.11E-06 8.21E-08 -2.19E-09

[0152] In this embodiment, the field curvature curve, F-Theta distortion curve, relative illumination curve, MTF 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

[0153] 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~0.02mm, which shows that the optical lens can well correct the field curvature.

[0154] Figure 24 The F-Theta distortion curve of embodiment 4 is shown, which represents the F-Theta distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the F-Theta 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.

[0155] Figure 25 The relative illumination curve of 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 80% at the maximum half field angle, which shows that the optical lens has good relative illumination.

[0156] ​Figure 26 The MTF (Modulation Transfer Function) curve of the optical lens of embodiment 4 is shown, which represents the modulation degree of lens imaging 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 of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0157] Figure 27 The axial aberration curve of embodiment 4 is shown, which represents the aberration of the optical axis at the imaging surface at each wavelength, 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-14 μm-4 μm, which shows that the optical lens can better correct the axial aberration.

[0158] Figure 28 The curve of the axial chromatic aberration of embodiment 4 is shown, which represents the chromatic aberration of different image heights on the imaging surface at each wavelength relative to the center wavelength (0.55 μm), the horizontal axis represents the axial chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view angle. As can be seen from the figure, the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, which shows 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 surface.

[0159] Please refer to Table 5 for 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, the maximum half field angle in radians θ, the chief ray angle CRA and the maximum field of view FOV of the optical lens, and the numerical values corresponding to each conditional expression in each embodiment.

[0160] Table 5

[0161]

[0162]

[0163] In summary of the above embodiments, the optical lens provided by the present application improves the imaging quality of the optical lens, reduces the aberration, and improves the imaging quality of the optical lens by reasonable configuration of each lens surface and reasonable matching of optical power.

[0164] 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 expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0165] 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 a limitation on the patent scope of the present application. It should be noted that, for those of ordinary skill 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, in total seven pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, the optical lens comprises in sequence: a first lens with negative refractive power, the object side surface of which is a convex surface and the image side surface of which is a concave surface; a second lens with negative refractive power, the object side surface of which is a convex surface and the image side surface of which is a concave surface; a third lens with positive refractive power, the object side surface of which is a concave surface and the image side surface of which is a convex surface; a fourth lens with positive refractive power, both the object side surface and the image side surface of which are convex surfaces; a fifth lens with positive refractive power, both the object side surface and the image side surface of which are convex surfaces; a sixth lens with negative refractive power, both the object side surface and the image side surface of which are concave surfaces; a seventh lens with positive refractive power, both the object side surface and the image side surface of which are convex surfaces; The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 100 < f3 / f ≤ 414.

20. The effective focal length f of the optical lens and the combined focal length f56 of the fifth lens and the sixth lens satisfy: -8.0 < f56 / f < -5.

5.

2. The optical lens of claim 1, wherein, The maximum field of view FOV of the optical lens and the aperture value FNO satisfy: 80° < FOV / FNO < 105°.

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: -4.8 < f1 / f < -3.

2.

4. 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: -4.9 < f2 / f < -3.

5.

5. The optical lens of claim 1, wherein, The object side surface curvature radius R13 of the seventh lens and the image side surface curvature radius R14 of the seventh lens satisfy: -1.7 < (R13-R14) / (R13+R14) < -1.

0.

6. The optical lens of claim 1, wherein, The central thickness CT3 of the third lens along the optical axis and the central thickness CT4 of the fourth lens along the optical axis satisfy: 1.0 < CT3 / CT4 < 1.

8.

7. The optical lens of claim 1, wherein, The combined focal length f12 of the first lens and the second lens and the combined focal length f34 of the third lens and the fourth lens satisfy: -0.9 < f12 / f34 < -0.

75.

8. The optical lens of claim 1, wherein, The object side surface aperture D1 of the first lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV satisfy: -0.5 < D1 / IH / tan(FOV / 2) < -0.

2.

9. The optical lens of claim 1, wherein, The refractive index Nd5 of the fifth lens and the refractive index Nd6 of the sixth lens satisfy: 0.1 < |Nd5-Nd6| ≤ 0.

14.

10. The optical lens of claim 1, wherein, The Abbe number Vd5 of the fifth lens and the Abbe number Vd6 of the sixth lens satisfy: 30 < |Vd5-Vd6| ≤ 40.02.

Images