Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses arranged along an optical axis from an object side to an imaging surface in sequence, wherein the first lens has a negative focal length, and an image side of the first lens is concave; the second lens has a positive focal length, and an object side of the second lens is concave, and an image side of the second lens is convex; a diaphragm; the third lens has a positive focal length, and an object side of the third lens is convex, and an image side of the third lens is convex; the fourth lens has a positive focal length, and an image side of the fourth lens is convex; the fifth lens has a negative focal length; the sixth lens has a negative focal length, and an image side of the sixth lens is concave; and the seventh lens has a positive focal length, and an object side of the seventh lens is convex. The optical lens adopts seven lenses, and through reasonable matching of lens shapes and focal length combinations of the lenses, the effects of a large field of view, a large aperture and miniaturization are achieved, so that the optical lens can better meet the requirements of a vehicle-mounted camera.

Description

TECHNICAL FIELD

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

[0002] With the development of automobile intelligence, the driving assistance function of vehicles is gradually enhanced, and the visual information collection is the core tool. With the improvement of the level of automatic driving, the requirements for vehicle-mounted cameras are also gradually improved, especially for front cameras. The front camera can enhance the active safety and driver assistance function, such as automatic emergency braking (AEB), adaptive cruise control (ACC), lane keeping assistance system (LKAS) and traffic jam assistance (TJA), etc. The front camera has the advantages of meeting high resolution, large field of view, good environmental adaptability, etc. However, it also has the disadvantages of too many lenses and too long optical total length, which is not conducive to the miniaturization of electronic systems. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens which has the advantages of large aperture, large field of view and miniaturization.

[0004] In the first aspect, the present application provides an optical lens, which has seven lenses in total, arranged in order along the optical axis from the object side to the imaging surface: a first lens with negative focal power, the image side of which is concave; a second lens with positive focal power, the object side of which is concave and the image side of which is convex; a stop; a third lens with positive focal power, the object side of which is convex and the image side of which is convex; a fourth lens with positive focal power, the image side of which is convex; a fifth lens with negative focal power; a sixth lens with negative focal power, the image side of which is concave; a seventh lens with positive focal power, the object side of which is convex; wherein the optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.8 < TTL / f < 7.2.

[0005] In some embodiments, the object side of the first lens is convex.

[0006] In some embodiments, the object side of the first lens is concave.

[0007] In some embodiments, the object side of the fourth lens is convex.

[0008] In some embodiments, the object side of the fourth lens is concave.

[0009] In some embodiments, the object side of the fifth lens is convex and the image side is concave.

[0010] In some embodiments, the object side of the fifth lens is concave and the image side is concave.

[0011] In some embodiments, the object-side surface of the fifth lens is concave, and the image-side surface of the fifth lens is convex.

[0012] In some embodiments, the object-side surface of the sixth lens is convex.

[0013] In some embodiments, the object-side surface of the sixth lens is concave.

[0014] In some embodiments, the image-side surface of the seventh lens is convex.

[0015] In some embodiments, the image-side surface of the seventh lens is concave.

[0016] In some embodiments, the second lens and the seventh lens have aspheric surfaces.

[0017] In some embodiments, the second lens and the fourth lens have aspheric surfaces.

[0018] In some embodiments, the fourth lens and the fifth lens are cemented to form a cemented lens.

[0019] In some embodiments, the sixth lens and the seventh lens are cemented to form a cemented lens.

[0020] In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.5.

[0021] In some embodiments, the effective aperture D1 of the object-side surface of the first lens, the real image height IH corresponding to the maximum field angle of the optical lens, and the maximum half field angle θ of the optical lens satisfy: 0.2 < D1 / IH / tan(θ) < 0.8.

[0022] In some embodiments, the sum of the curvature radius R3 of the object-side surface of the second lens, the curvature radius R4 of the image-side surface of the second lens, and the central thickness CT2 of the second lens satisfy: 4.2 < R3 / (R4+CT2) < 60.0.

[0023] In some embodiments, the effective focal length f of the optical lens and the curvature radius R1 of the object-side surface of the first lens satisfy: 20 < |R1 / f|.

[0024] In some embodiments, the material refractive index Nd6 of the sixth lens and the material refractive index Nd7 of the seventh lens satisfy: 1.1 < Nd6 / Nd7 < 1.3; and the material Abbe number Vd6 of the sixth lens and the material Abbe number Vd7 of the seventh lens satisfy: 0.2 < Vd6 / Vd7 < 0.5.

[0025] In a second aspect, the present application further provides an optical lens, which comprises seven lenses in sequence from an object side to an image plane along an optical axis, and the seven lenses are: a first lens with negative focal power, an image side of which is concave; a second lens with positive focal power, an object side of which is concave and an image side of which is convex; a stop; a third lens with positive focal power, an object side of which is convex and an image side of which is convex; a fourth lens with positive focal power, an image side of which is convex; a fifth lens with negative focal power; a sixth lens with negative focal power, an image side of which is concave; and a seventh lens with positive focal power, an object side of which is convex; wherein a real image height IH corresponding to a maximum field angle of the optical lens and an effective focal length f of the optical lens satisfy: 1.8 < IH / f < 2.2.

[0026] In some embodiments, an optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.8 < TTL / f < 7.2.

[0027] In a third aspect, the present application further provides an optical lens, which comprises seven lenses in sequence from an object side to an image plane along an optical axis, and the seven lenses are: a first lens with negative focal power, an image side of which is concave; a second lens with positive focal power, an object side of which is concave and an image side of which is convex; a stop; a third lens with positive focal power, an object side of which is convex and an image side of which is convex; a fourth lens with positive focal power, an image side of which is convex; a fifth lens with negative focal power; a sixth lens with negative focal power, an image side of which is concave; and a seventh lens with positive focal power, an object side of which is convex; wherein a real image height IH corresponding to a maximum field angle of the optical lens, an effective focal length f of the optical lens and a maximum half field angle θ of the optical lens satisfy: 0.3 < (IH / 2) / [fxtan(θ)] < 0.6.

[0028] In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.5.

[0029] Compared with the prior art, the present application has the beneficial effects that: the present application adopts seven lenses, and through reasonable matching of lens shapes and focal power combinations of the lenses, the effects of large field of view, large aperture and miniaturization are achieved, so that the optical lens can better meet the requirements of a vehicle-mounted camera. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 FIG. 1 is a structure diagram of an optical lens according to an embodiment of the present application.

[0031] Figure 2 FIG. 2 is a field curvature curve of the optical lens according to the embodiment of the present application.

[0032] Figure 3The relative illumination curve of the optical lens in Embodiment 1 of the present application.

[0033] Figure 4 The MTF curve of the optical lens in Embodiment 1 of the present application.

[0034] Figure 5 The axial aberration curve of the optical lens in Embodiment 1 of the present application.

[0035] Figure 6 The lateral chromatic aberration curve of the optical lens in Embodiment 1 of the present application.

[0036] Figure 7 The structure diagram of the optical lens in Embodiment 2 of the present application.

[0037] Figure 8 The field curvature curve of the optical lens in Embodiment 2 of the present application.

[0038] Figure 9 The relative illumination curve of the optical lens in Embodiment 2 of the present application.

[0039] Figure 10 The MTF curve of the optical lens in Embodiment 2 of the present application.

[0040] Figure 11 The axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0041] Figure 12 The lateral chromatic aberration curve of the optical lens in Embodiment 2 of the present application.

[0042] Figure 13 The structure diagram of the optical lens in Embodiment 3 of the present application.

[0043] Figure 14 The field curvature curve of the optical lens in Embodiment 3 of the present application.

[0044] Figure 15 The relative illumination curve of the optical lens in Embodiment 3 of the present application.

[0045] Figure 16 The MTF curve of the optical lens in Embodiment 3 of the present application.

[0046] Figure 17 The axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0047] Figure 18 The lateral chromatic aberration curve of the optical lens in Embodiment 3 of the present application.

[0048] Figure 19 The structure diagram of the optical lens in Embodiment 4 of the present application.

[0049] Figure 20 Field curvature curve of the optical lens in Embodiment 4 of the present application.

[0050] Figure 21 Relative illumination curve of the optical lens in Embodiment 4 of the present application.

[0051] Figure 22 MTF curve of the optical lens in Embodiment 4 of the present application.

[0052] Figure 23 Axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0053] Figure 24 Vignetting curve of the optical lens in Embodiment 4 of the present application.

[0054] Figure 25 Structure diagram of the optical lens in Embodiment 5 of the present application.

[0055] Figure 26 Field curvature curve of the optical lens in Embodiment 5 of the present application.

[0056] Figure 27 Relative illumination curve of the optical lens in Embodiment 5 of the present application.

[0057] Figure 28 MTF curve of the optical lens in Embodiment 5 of the present application.

[0058] Figure 29 Axial aberration curve of the optical lens in Embodiment 5 of the present application.

[0059] Figure 30 Vignetting curve of the optical lens in Embodiment 5 of the present application. DETAILED DESCRIPTION

[0060] 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 understood that the detailed description is merely descriptive of embodiments of the present application and is not intended to limit the scope of the present application in any way. Throughout the specification, like reference numerals refer to like elements. The expression “and / or” includes any and all combinations of one or more of the associated listed items.

[0061] It should be noted that the expressions first, second, third, etc. in the present specification 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.

[0062] 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.

[0063] 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.

[0064] 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 "one or more embodiments of the present application". Also, the word "exemplary" is intended to mean an example or an illustration.

[0065] 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.

[0066] 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.

[0067] The optical lens according to the embodiment of the present application comprises, in order from the object side to the image side: a first lens, a second lens, a diaphragm, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and a filter and a protective glass.

[0068] In some embodiments, the first lens can have a negative focal power, which is beneficial for reducing the incident light angle to effectively share the large field of view on the object side. The image side of the first lens is concave, which is beneficial for collecting as much edge field of view light as possible into the rear optical system to achieve large angle light collection. Further, the refractive index Nd of the first lens is greater than 1.70, and the use of a first lens with a higher refractive index is beneficial for reducing the effective working aperture of the first lens to avoid excessive divergence of light, which leads to an excessively large aperture of the rear lens of the optical lens.

[0069] In some embodiments, the second lens can have a positive focal power, which is beneficial for converging light while reducing the light deflection angle to allow smooth transition of the light path. The object side of the second lens is concave, and the image side is convex, which is beneficial for transitioning and adjusting the light from the first lens that is deflected too much.

[0070] In some embodiments, the third lens can have a positive focal power and both the object side and the image side are convex, which is beneficial for further converging light while reducing the light deflection angle to allow smooth transition of the light path.

[0071] In some embodiments, the fourth lens can have a positive focal power, which is beneficial for converging light while reducing the light deflection angle to allow smooth transition of the light path.

[0072] In some embodiments, the fifth lens can have a negative focal power, which is beneficial for balancing various aberrations generated by the optical lens to improve the imaging quality of the optical lens.

[0073] In some embodiments, the sixth lens can have a negative focal power, which is beneficial for increasing the imaging area of the optical lens to improve the imaging quality of the optical lens.

[0074] In some embodiments, the seventh lens can have a positive focal power, which is beneficial for suppressing the angle of the edge field of view incident on the imaging surface to effectively transfer more light beams to the imaging surface, thereby improving the imaging quality of the optical lens. The object side of the seventh lens is convex, which is beneficial for improving the relative luminance of the edge field of view to avoid the generation of dark corners and improve the imaging quality of the optical lens.

[0075] In some embodiments, the fourth lens and the fifth lens can be cemented to form a cemented lens, or the sixth lens and the seventh lens can be cemented to form a cemented lens, which is used to share the chromatic aberration correction of the optical lens, improve the resolution of the optical lens, and at the same time make the structure of the optical lens compact, which is beneficial for realizing the miniaturization of the optical lens.

[0076] In some embodiments, the diaphragm can be arranged between the second lens and the third lens, which is beneficial for collecting the range of light emitted from the front end of the optical lens to reduce the aperture of the rear end of the optical lens.

[0077] In some embodiments, the optical lens satisfies: 1.60≤FNO. Satisfying the above range is conducive to achieving a large aperture characteristic, and ensuring the clarity of an image in a low-light environment or at night.

[0078] In some embodiments, the optical lens satisfies: 55°<θ. Satisfying the above range is conducive to achieving a wide-angle characteristic, so as to be able to obtain more scene information and meet the needs of wide-range detection.

[0079] In some embodiments, the optical lens satisfies: 10°<CRA<30°. Satisfying the above range can make the CRA of the optical lens have a larger allowable error range with the CRA of a photosensitive element of a chip, thereby improving the adaptation capability of the optical lens to the image sensor.

[0080] In some embodiments, the optical lens satisfies: 5.8<TTL / f<7.2. Satisfying the above range can effectively limit the length and volume of the optical lens, thereby achieving miniaturization of the optical lens.

[0081] In some embodiments, the optical lens satisfies: 2.8<IH / EPD<3.5. Satisfying the above range is conducive to balancing the size of an image surface and the relative luminance of an edge field of view, thereby achieving a balance between a large field of view, a large aperture, and miniaturization.

[0082] In some embodiments, the optical lens satisfies: 0.2<D1 / IH / tan(θ)<0.8. Satisfying the above range is conducive to reducing the front aperture of the optical lens, thereby achieving miniaturization of the optical lens.

[0083] In some embodiments, the optical lens satisfies: 4.2<R3 / (R4+CT2)<60.0. Satisfying the above range is conducive to correcting field curvature by setting the second lens to be a meniscus thick lens, thereby facilitating correction of aberrations of the entire optical lens.

[0084] In some embodiments, the optical lens satisfies: 20<|R1 / f|. Satisfying the above range can effectively control the surface curvature of the object side surface of the first lens, increase the field of view, and control the front aperture of the optical lens.

[0085] In some embodiments, the material refractive index Nd6 of the sixth lens and the material refractive index Nd7 of the seventh lens satisfy: 1.1 < Nd6 / Nd7 < 1.3; the material Abbe number Vd6 of the sixth lens and the material Abbe number Vd7 of the seventh lens satisfy: 0.2 < Vd6 / Vd7 < 0.5. Satisfying the above ranges is conducive to correcting the chromatic aberration of the optical lens, while making the structure of the optical lens compact and making the light transition smooth, so as to achieve the balance between miniaturization and high resolution of the optical lens.

[0086] 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 angle satisfy: 1.8 < IH / f < 2.2. Satisfying the above range can not only achieve wide-angle characteristics to meet the demand for a wide range of shooting, but also achieve large image characteristics to improve the imaging quality of the optical lens.

[0087] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f and the maximum half field of view angle θ of the optical lens satisfy: 0.3 < (IH / 2) / [f x tan(θ)] < 0.6. Satisfying the above range is conducive to realizing small distortion of the optical lens.

[0088] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -2.0 < f1 / f < -1.0. Satisfying the above range can make the first lens have appropriate negative refractive power, which is conducive to the moderate change of the refraction angle of the incident light, avoids excessive change of the refraction angle to generate too much aberration, and helps more light enter the rear optical system to increase the illumination and improve the imaging quality of the optical lens.

[0089] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 3.0 < f2 / f < 6.0. Satisfying the above range can make the second lens have appropriate positive refractive power, and by reasonably limiting the refractive power of the second lens, the influence of the second lens on the back focus shift under high and low temperature conditions can be reduced, thereby improving the temperature performance of the optical lens.

[0090] 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 < 4.0. Satisfying the above range can make the third lens have appropriate positive refractive power, which is conducive to the smooth transition of the light path and improves the imaging quality of the optical lens.

[0091] 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 < 5.5. Satisfying the above range can make the fourth lens have appropriate positive refractive power, which is conducive to the smooth transition of the light path and improves the imaging quality of the optical lens.

[0092] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -31.0 < f5 / f < -2.0. Satisfying the above range, the fifth lens can have appropriate negative refractive power, which is conducive to balancing various aberrations of the optical lens and improving the imaging quality of the optical lens.

[0093] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -4.0 < f6 / f < -1.0. Satisfying the above range, the sixth lens can have appropriate negative refractive power, which is conducive to balancing various aberrations of the optical lens and improving the imaging quality of the optical lens.

[0094] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.0 < f7 / f < 13.0. Satisfying the above range, the seventh lens can have appropriate positive refractive power, which is conducive to improving the convergence ability of the edge field of view light and improving the relative luminance of the optical lens.

[0095] In order to make the system have better optical performance, a plurality of aspheric lenses are used in the lens, and the shape of each aspheric surface of the optical lens satisfies the following equation:

[0096]

[0097] 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, 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.

[0098] 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 the 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 modes, and are included in the protection scope of the application.

[0099] Embodiment 1

[0100] Please refer to Figure 1 , which is a structural schematic diagram of the optical lens provided in the embodiment 1 of the application. The optical lens includes, in order from the object side to the imaging surface S18 along the optical axis, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1 and a protective glass G2.

[0101] The first lens L1 has negative focal power, the object side S1 is convex at the near optical axis, and the image side S2 is concave; the second lens L2 has positive focal power, the object side S3 is concave, and the image side S4 is convex; the third lens L3 has positive focal power, the object side S5 is convex, and the image side S6 is convex; the fourth lens L4 has positive focal power, the object side S7 is convex, and the image side is convex; the fifth lens L5 has negative focal power, the object side is concave, and the image side S9 is convex, and the fourth lens L4 and the fifth lens L5 are cemented into a cemented lens, and the cemented surface is S8; the sixth lens L6 has negative focal power, the object side S10 is convex, and the image side S11 is concave; the seventh lens L7 has positive focal power, the object side S12 is convex at the near optical axis, and the image side S13 is concave at the near optical axis; the filter G1 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0102] The related parameters of the lenses in the optical lens in Embodiment 1 are shown in Table 1-1.

[0103] Table 1-1

[0104]

[0105] The curve coefficients of the aspherical lenses of the optical lens in Embodiment 1 are shown in Table 1-2.

[0106] Table 1-2

[0107]

[0108] Figure 2 The field curvature curve diagram of Embodiment 1 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 of view (unit: °). As can be seen from the figure, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.025 mm, which shows that the optical lens can very well correct the field curvature.

[0109] Figure 3 The relative luminance curve diagram of Embodiment 1 is shown, which represents the relative luminance values of different field angles on the imaging surface, the horizontal axis represents the half field of view (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 60% at the maximum half field of view, which shows that the optical lens has very good relative luminance.

[0110] Figure 4A modulation transfer function (MTF) curve of the optical lens of Embodiment 1 is shown, which represents the imaging modulation degree of different spatial frequencies in each field of view, the horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents 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 0-160 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 capability in low and high frequency cases.

[0111] Figure 5 An axial aberration curve of the optical lens of Embodiment 1 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 ±15 μm, which shows that the optical lens can better correct the axial aberration.

[0112] Figure 6 A curve of the optical lens of Embodiment 1 is shown, which represents the color difference of different image heights on the imaging surface at each wavelength relative to the center wavelength (0.55 μm), the horizontal axis represents the vertical color difference value (unit: μm) of each wavelength relative to the center wavelength, and the vertical axis represents the normalized field angle. As can be seen from the figure, the vertical color difference of the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, which shows that the optical lens can very well correct the color difference of the edge field of view and the secondary spectrum of the entire image surface.

[0113] Embodiment 2

[0114] Please refer to Figure 7 , which is a structural schematic diagram of the optical lens provided in Embodiment 2 of the present application, which comprises, along the optical axis from the object side to the imaging surface S18, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0115] The first lens L1 has negative focal power, the object side S1 is a concave surface, and the image side S2 is a concave surface; the second lens L2 has positive focal power, the object side S3 is a concave surface, and the image side S4 is a convex surface; the third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side S6 is a convex surface; the fourth lens L4 has positive focal power, the object side S7 is a convex surface, and the image side is a convex surface; the fifth lens L5 has negative focal power, the object side is a concave surface, and the image side S9 is a convex surface; the fourth lens L4 and the fifth lens L5 are cemented into a cemented lens, the cemented surface is S8; the sixth lens L6 has negative focal power, the object side S10 is a convex surface, and the image side S11 is a concave surface; the seventh lens L7 has positive focal power, the object side S12 is a convex surface at the near optical axis, and the image side S13 is a concave surface at the near optical axis; the filter G1 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0116] The related parameters of the lenses in the optical lens in Example 2 are shown in Table 2-1.

[0117] Table 2-1

[0118]

[0119] The surface coefficients of the aspheric lenses of the optical lens in Example 2 are shown in Table 2-2.

[0120] Table 2-2

[0121]

[0122] Figure 8 to Figure 12 The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the transverse chromatic aberration curve of Example 2 are shown. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.025 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 60% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is greater than 0.45 in the full field of view, and in the range of 0-160 lp / mm, the MTF curve is uniformly and smoothly decreased 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; the shift of the axial aberration is controlled within ±15 μm, which indicates that the optical lens can correct the axial aberration well; the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the entire image surface very well.

[0123] Example 3

[0124] Please refer toFigure 13 Fig. 3 shows a structural schematic diagram of an optical lens provided in Embodiment 3 of the present application, which comprises, in sequence from the object side to the imaging surface S18 along the optical axis, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1 and a protective glass G2.

[0125] The first lens L1 has a negative focal length, the object side S1 is concave, and the image side S2 is concave; the second lens L2 has a positive focal length, the object side S3 is concave, and the image side S4 is convex; the third lens L3 has a positive focal length, the object side S5 is convex, and the image side S6 is convex; the fourth lens L4 has a positive focal length, the object side S7 is convex, and the image side is convex; the fifth lens L5 has a negative focal length, the object side is concave, and the image side S9 is concave; the fourth lens L4 and the fifth lens L5 are cemented into a cemented lens, and the cemented surface is S8; the sixth lens L6 has a negative focal length, the object side S10 is convex, and the image side S11 is concave; the seventh lens L7 has a positive focal length, the object side S12 is convex near the optical axis, and the image side S13 is concave near the optical axis; the filter G1 has a flat object side S14 and a flat image side S15; and the protective glass G2 has a flat object side S16 and a flat image side S17.

[0126] The related parameters of the lenses in the optical lens in Embodiment 3 are shown in Table 3-1.

[0127] Table 3-1

[0128]

[0129]

[0130] The curve coefficients of the aspherical lenses of the optical lens in Embodiment 3 are shown in Table 3-2.

[0131] Table 3-2

[0132]

[0133] Figure 14 to Figure 18The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the axial chromatic aberration curve of the optical lens of embodiment 3 are shown. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.04 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 75% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is all above 0.4 within the full field of view, and the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view within the range of 0-160 lp / mm, which has good imaging quality and good detail resolution ability in the case of low frequency and high frequency; the offset of the axial aberration is controlled within ±10 μm, which indicates that the optical lens can correct the axial aberration well; the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0134] Embodiment 4

[0135] Referring to Figure 19 , which is a structural schematic diagram of the optical lens provided in embodiment 4 of the present application, the optical lens comprises, along the optical axis from the object side to the imaging surface S18, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0136] The first lens L1 has negative focal power, the object side S1 thereof is a convex surface at the near optical axis, and the image side S2 thereof is a concave surface; the second lens L2 has positive focal power, the object side S3 thereof is a concave surface, and the image side S4 thereof is a convex surface; the third lens L3 has positive focal power, the object side S5 thereof is a convex surface, and the image side S6 thereof is a convex surface; the fourth lens L4 has positive focal power, the object side S7 thereof is a convex surface, and the image side thereof is a convex surface; the fifth lens L5 has negative focal power, the object side thereof is a concave surface, and the image side S9 thereof is a convex surface; the fourth lens L4 and the fifth lens L5 are cemented into a cemented lens, and the cemented surface thereof is S8; the sixth lens L6 has negative focal power, the object side S10 thereof is a convex surface, and the image side S11 thereof is a concave surface; the seventh lens L7 has positive focal power, the object side S12 thereof is a convex surface at the near optical axis, and the image side S13 thereof is a concave surface at the near optical axis; the filter G1 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0137] The related parameters of the lenses in the optical lens of embodiment 4 are shown in Table 4-1.

[0138] Table 4-1

[0139]

[0140] The curve coefficients of the aspherical lens of the optical lens in embodiment 4 are shown in table 4-2.

[0141] Table 4-2

[0142]

[0143]

[0144] Figure 20 to Figure 24 The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the axial chromatic aberration curve of embodiment 4 are shown. It can be seen from the figures that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.035 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 75% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is all above 0.4 within the full field of view, and in the range of 0-160 lp / mm, the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view, and the optical lens has good imaging quality and good detail resolution ability in the case of low frequency and high frequency; the offset of the axial aberration is controlled within ±15 μm, which indicates that the optical lens can correct the axial aberration well; the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1.5 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0145] Embodiment 5

[0146] Please refer to Figure 25 , which is a structural schematic diagram of the optical lens provided in embodiment 5 of the present application, and the optical lens comprises, along the optical axis from the object side to the imaging surface S18, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0147] The first lens L1 has negative focal power, the object side S1 is convex at the near optical axis, and the image side S2 is concave; the second lens L2 has positive focal power, the object side S3 is concave, and the image side S4 is convex; the third lens L3 has positive focal power, the object side S5 is convex, and the image side S6 is convex; the fourth lens L4 has positive focal power, the object side S7 is concave at the near optical axis, and the image side S8 is convex at the near optical axis; the fifth lens L5 has negative focal power, the object side S9 is convex, and the image side S10 is concave; the sixth lens L6 has negative focal power, the object side S11 is concave, and the image side is concave; the seventh lens L7 has positive focal power, the object side is convex, and the image side S13 is convex, and the sixth lens L6 and the seventh lens L7 are cemented into a cemented lens, the cemented surface is S12; the filter G1 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0148] The related parameters of the lenses in the optical lens in Example 5 are shown in Table 5-1.

[0149] Table 5-1

[0150]

[0151]

[0152] The surface coefficients of the aspheric lenses of the optical lens in Example 5 are shown in Table 5-2.

[0153] Table 5-2

[0154]

[0155] Figure 26 to Figure 30 The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the transverse chromatic aberration curve of Example 5 are shown. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.04 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 70% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is above 0.4 in the full field of view, and in the range of 0-160 lp / mm, the MTF curve is uniformly and smoothly decreased 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; the shift of the axial aberration is controlled within ±15 μm, which indicates that the optical lens can correct the axial aberration well; the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the entire image surface very well.

[0156] Please refer to Table 6 for the optical characteristics of the above-mentioned embodiments, including the effective focal length f, the half field of view θ, the entrance pupil diameter EPD, the total track length TTL, the F-number FNO, the image height IH, and the numerical values corresponding to each conditional expression in the embodiments of the optical lens.

[0157] Table 6

[0158] Parameters and conditional expressions Example 1 Example 2 Example 3 Example 4 Example 5 f (mm) 4.36 4.97 4.91 4.39 4.27 θ (°) 70.00 60.00 60.00 70.00 70.00 EPD (mm) 2.73 3.11 3.07 2.74 2.67 TTL (mm) 28.95 29.90 29.90 29.28 29.90 FNO 1.60 1.60 1.60 1.60 1.60 IH (mm) 8.95 9.41 9.30 8.91 8.94 CRA (°) 19.80 20.00 20.00 16.34 19.30 TTL / f 6.64 6.01 6.09 6.68 7.01 IH / EPD 3.28 3.03 3.03 3.25 3.35 D1 / IH / tan(θ) 0.49 0.73 0.73 0.49 0.49 R3 / (R4+CT2) 11.41 11.48 55.29 4.50 5.63 |R1 / f| 1359.34 91.10 112.89 359.70 22.06 Nd6 / Nd7 1.26 1.12 1.15 1.23 1.13 Vd6 / Vd7 0.42 0.38 0.36 0.29 0.38 IH / f 2.05 1.89 1.89 2.03 2.10 (IH / 2) / [f x tan(θ)] 0.37 0.55 0.55 0.37 0.38 f1 / f -1.66 -1.59 -1.47 -1.43 -1.56 f2 / f 4.16 3.93 3.66 4.56 4.86 f3 / f 2.69 2.31 2.26 3.01 2.66 f4 / f 1.88 4.12 1.70 1.95 5.20 f5 / f -3.30 -30.42 -2.15 -3.48 -5.59 f6 / f -2.80 -2.23 -2.35 -3.25 -1.67 f7 / f 12.12 12.76 5.01 6.54 1.64

[0159] In summary, the optical lens of the embodiments of the present application realizes the effects of large field of view, large aperture, and miniaturization by reasonably matching the lens shape and power combination between each lens.

[0160] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0161] The above-mentioned embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical lens, in total seven pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, there are: a first lens with negative refractive power, whose image side surface is a concave surface; a second lens with positive refractive power, whose object side surface is a concave surface and whose image side surface is a convex surface; a diaphragm; a third lens with positive refractive power, whose object side surface is a convex surface and whose image side surface is a convex surface; a fourth lens with positive refractive power, whose image side surface is a convex surface; a fifth lens with negative refractive power; a sixth lens with negative refractive power, whose image side surface is a concave surface; a seventh lens with positive refractive power, whose object side surface is a convex surface near the optical axis; wherein the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.8 < TTL / f < 7.2; the sum of the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens, and the central thickness CT2 of the second lens satisfies: 4.2 < R3 / (R4+CT2) < 60.

0.

2. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.

5.

3. The optical lens of claim 1, wherein, the effective aperture D1 of the object side surface of the first lens, the real image height IH corresponding to the maximum field angle of the optical lens, and the maximum half field angle θ of the optical lens satisfy: 0.2 < D1 / IH / tan(θ) < 0.

8.

4. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the curvature radius R1 of the object side surface of the first lens satisfy: 20 < |R1 / f|.

5. The optical lens of claim 1, wherein, the material refractive index Nd6 of the sixth lens and the material refractive index Nd7 of the seventh lens satisfy: 1.1 < Nd6 / Nd7 < 1.3; the material Abbe number Vd6 of the sixth lens and the material Abbe number Vd7 of the seventh lens satisfy: 0.2 < Vd6 / Vd7 < 0.5.

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