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 of the first lens is a concave surface, and the image side surface of the first lens is a concave surface; a second lens with positive optical power, wherein the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a convex surface; a third lens with negative optical power, wherein the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex surface; a fourth lens with positive optical power, wherein the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface; a sixth lens with negative optical power, wherein the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a concave surface; and a seventh lens with positive optical power, wherein the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a concave surface. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and make the lens have one or more advantages such as a large target surface, a large aperture, high imaging quality and the like.

Description

TECHNICAL FIELD

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

[0002] With the increasing demand for driving experience, vehicle application optical lenses are increasingly used in intelligent driving, and the status of vehicle optical lenses in the automotive industry is continuously improving.

[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. In addition to the requirements of optical lenses for ADAS systems, such as light, thin, small shape and high pixel, high resolution, the optical lenses are also required to have clear imaging under low illumination conditions, so it is necessary to develop an optical lens with good imaging effect. SUMMARY

[0004] To solve the above problems, the present application provides an optical lens with excellent imaging quality.

[0005] The technical scheme adopted by the present application is:

[0006] An optical lens, comprising seven lenses, arranged along the optical axis from the object side to the imaging surface in order:

[0007] The first lens has a negative focal length, the object side surface is concave, and the image side surface is concave;

[0008] The second lens has a positive focal length, the object side surface is convex, and the image side surface is convex;

[0009] The third lens has a negative focal length, the object side surface is concave, and the image side surface is convex;

[0010] The fourth lens has a positive focal length, the object side surface is convex, and the image side surface is convex;

[0011] The fifth lens has a positive focal length, the object side surface is convex, and the image side surface is concave;

[0012] The sixth lens has a negative focal length, the object side surface is convex, and the image side surface is concave;

[0013] The seventh lens has a positive focal length, the object side surface is convex, and the image side surface is concave;

[0014] The effective focal length f of the optical lens and the image-side curvature radius R6 of the third lens satisfy -2.8 < R6 / f < -2.4; the object-side curvature radius R1 of the first lens and the image-side curvature radius R2 of the first lens satisfy 1.16 < (R1-R2) / (R1+R2) < 1.27; and the object-side curvature radius R13 of the seventh lens and the image-side curvature radius R14 of the seventh lens satisfy -0.35 < (R13-R14) / (R13+R14) < -0.2.

[0015] Further preferably, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy 4.5 < TTL / f < 5.5.

[0016] Further preferably, the effective focal length f of the optical lens, the maximum field of view FOV of the optical lens, and the real image height IH corresponding to the maximum field of view of the optical lens satisfy 0.85 < (IH / 2) / (f*tan(FOV / 2)) < 0.92.

[0017] Further preferably, the real image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy 1.85 < IH / EPD < 2.1.

[0018] Further preferably, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy 1 < IH / f < 1.3.

[0019] Further preferably, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy 0.6 < BFL / f < 0.8.

[0020] Further preferably, the effective focal length f of the optical lens, the radian value θ of the maximum half field of view of the optical lens, and the object-side half-aperture radius d1 of the first lens satisfy 0.5 < f*θ / d1 < 0.7.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy -1.95 < f1 / f < -1.7; and the focal length f1 of the first lens and the focal length f2 of the second lens satisfy -0.8 < f1 / f2 < -0.6.

[0022] Further preferably, the object-side curvature radius R3 of the second lens and the image-side curvature radius R4 of the second lens satisfy -3.1 < (R3-R4) / (R3+R4) < -1.8.

[0023] It is further preferred that the object side surface radius of curvature R1 of the first lens and the object side surface sagittal radius of the first lens Sag1 satisfy: 203 < R1 / Sag1 < 426.

[0024] The optical lens provided by the application adopts seven lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens is improved, the aberration is reduced, and the imaging quality of the optical lens is improved, so that the lens has one or more advantages such as a large target surface, a large aperture, high imaging quality, and the like. BRIEF DESCRIPTION OF DRAWINGS

[0025] 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:

[0026] Figure 1 It is a structure schematic diagram of the optical lens in the embodiment 1 of the application.

[0027] Figure 2 It is a field curvature curve diagram of the optical lens in the embodiment 1 of the application.

[0028] Figure 3 It is an F-Tan(Theta) distortion curve diagram of the optical lens in the embodiment 1 of the application.

[0029] Figure 4 It is an MTF curve diagram of the optical lens in the embodiment 1 of the application.

[0030] Figure 5 It is a structure schematic diagram of the optical lens in the embodiment 2 of the application.

[0031] Figure 6 It is a field curvature curve diagram of the optical lens in the embodiment 2 of the application.

[0032] Figure 7 It is an F-Tan(Theta) distortion curve diagram of the optical lens in the embodiment 2 of the application.

[0033] Figure 8 It is an MTF curve diagram of the optical lens in the embodiment 2 of the application.

[0034] Figure 9 It is a structure schematic diagram of the optical lens in the embodiment 3 of the application.

[0035] Figure 10 It is a field curvature curve diagram of the optical lens in the embodiment 3 of the application.

[0036] Figure 11 It is an F-Tan(Theta) distortion curve diagram of the optical lens in the embodiment 3 of the application.

[0037] Figure 12 MTF curve of the optical lens in Embodiment 3 of the present application.

[0038] Figure 13 schematic structural diagram of the optical lens in Embodiment 4 of the present application.

[0039] Figure 14 field curvature curve of the optical lens in Embodiment 4 of the present application.

[0040] Figure 15 F-Tan(Theta) distortion curve of the optical lens in Embodiment 4 of the present application.

[0041] Figure 16 MTF curve of the optical lens in Embodiment 4 of the present application.

[0042] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0043] For better understanding of the present application, various aspects of the present application will be described in more detail with reference to the drawings. It should be understood that these detailed descriptions are only descriptions of embodiments of the present application and do not limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0044] It should be noted that in the present specification, the expressions first, second, third, etc. are only 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.

[0045] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn strictly to scale.

[0046] In this context, 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.

[0047] It should also be understood that the use of the terms "including", "including having", "having", "containing", and / or "containing having" when used in this specification intends that existence of stated features, elements and / or components but does not exclude the presence or addition of one or more other features, elements, components, and / or groups thereof. In addition, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the term "exemplary" is intended to refer to an example or illustration.

[0048] 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 will be further understood that terms, such as those defined in commonly used dictionaries, 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.

[0049] It should be noted that the embodiments and features of the embodiments in the present application 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.

[0050] The optical lens provided by the embodiments of the present application comprises seven lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface as the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens.

[0051] In some embodiments, the first lens can have a negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a concave surface. The second lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface. The third lens can have a negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface. The fourth lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface. The fifth lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface. The sixth lens can have a negative focal power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface. The seventh lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface.

[0052] In some embodiments, the optical lens can further comprise a diaphragm, which can be located between the third lens and the fourth lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging. When the diaphragm is located between the third lens and the fourth lens, the correction of the diaphragm aberration is facilitated.

[0053] In some embodiments, the optical lens can further include a filter, the filter and the protective glass are sequentially arranged along the optical axis between the seventh lens and the imaging surface. The filter is used to filter out interference light, preventing the interference light from reaching the imaging surface of the optical lens and affecting normal imaging. The protective glass plays a role in protecting the optical lens, preventing the photosensitive chip from being damaged, and can improve the impact resistance and scratch resistance of the optical lens, while having little effect on the imaging quality of the optical lens.

[0054] In some embodiments, the fifth lens and the sixth lens can be bonded to form a bonded 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; 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.

[0055] In some embodiments, the effective focal length f of the optical lens and the image side surface curvature radius R6 of the third lens satisfy: -2.8 < R6 / f < -2.4. Satisfying the above range can make the light transition to the rear lens more gently, which is more conducive to reducing the front aperture of the lens, further reducing the size of the lens, and further realizing miniaturization.

[0056] In some embodiments, the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy: 1.16 < (R1-R2) / (R1+R2) < 1.27. Satisfying the above range can make the collected light enter the rear optical system in the form of divergence as much as possible, while effectively reducing the angle between the edge field light and the object side surface of the first lens when the light is incident, and improving the overall edge relative luminance of the lens.

[0057] In some embodiments, the object side surface curvature radius R13 of the seventh lens and the image side surface curvature radius R14 of the seventh lens satisfy: -0.35 < (R13-R14) / (R13+R14) < -0.2. Satisfying the above range adjusts the optical path difference between different field lights, appropriately weakens the light convergence trend, and makes the subsequent light converge to the image plane gently.

[0058] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4.5 < TTL / f < 5.5. Satisfying the above range is conducive to realizing miniaturization and long focus of the entire lens.

[0059] In some embodiments, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens, and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.85 < (IH / 2) / (f x tan(FOV / 2)) < 0.92. Satisfying the above range can control the optical lens to have smaller distortion, and improve the imaging quality of the optical lens.

[0060] In some embodiments, a real image height IH corresponding to a maximum field of view angle of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy: 1.85<IH / EPD<2.1. Satisfying the above range is beneficial to increase the light quantity, so that the brightness of the peripheral field of view and the central field of view is more uniform.

[0061] In some embodiments, a real image height IH corresponding to a maximum field of view angle of the optical lens and an effective focal length f of the optical lens satisfy: 1<IH / f<1.3. Satisfying the above range controls the image height and the focal length of the optical lens within a reasonable range, which is helpful for the optical lens to have a large image surface and improve the imaging quality.

[0062] In some embodiments, an effective focal length f of the optical lens and a back focal length BFL of the optical lens satisfy: 0.6<BFL / f<0.8. Satisfying the above range limits the optical lens to have a suitable back focus, which is convenient for reasonably arranging the positions of the lenses and reduces the difficulty of processing and assembling.

[0063] In some embodiments, a total length TTL of the optical lens and a sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.8<∑CT / TTL<0.9. Satisfying the above range reasonably configures the total length of the optical lens and the sum of the thicknesses of the lenses, which is helpful for realizing high-pixel characteristics and improving the imaging quality of the optical lens.

[0064] In some embodiments, an effective focal length f of the optical lens, an arc value θ of a maximum half field of view angle of the optical lens, and a half entrance pupil diameter d1 of the object side surface of the first lens satisfy: 0.5<f×θ / d1<0.7. Satisfying the above range controls the focal length of the optical lens, the arc value corresponding to the maximum half field of view angle of the optical lens, and the front end diameter of the optical lens, so that the balance of the focal length, the field of view, and the diameter of the optical lens can be realized.

[0065] In some embodiments, an effective focal length f of the optical lens and a focal length f1 of the first lens satisfy: -1.95<f1 / f<-1.7. Satisfying the above range makes the first lens have a negative refractive power, which has a diverging effect on the light passing through the first lens, and is beneficial to realize a small front end diameter.

[0066] In some embodiments, an effective focal length f of the optical lens and a focal length f2 of the second lens satisfy: 2<f2 / f<3. Satisfying the above range limits the second lens to have a proper positive refractive power, which has an effect of converging light, and is beneficial to further converge the light passing through the first lens, lower the height of the peripheral light, reduce the diameter of the rear end lens, balance the aberration, and improve the resolution.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -31 < f3 / f < -23. Satisfying the above range has the effect of diverging light rays, can disperse the central light rays and the edge light rays of each field of view, can make the rear optical system have a larger light receiving surface to receive the light rays emitted by the third lens, realize a larger light receiving amount, and is beneficial to increasing the relative illumination.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2 < f4 / f < 2.5. Satisfying the above range is beneficial to the convergence of light rays, can make the diverging light rays smoothly enter the rear optical system, better realize high-quality imaging of the lens, and can effectively correct the distortion of the edge field of view, reduce the deformation degree of the edge of the captured image, and improve the image quality.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 2 < f5 / f < 2.5. Satisfying the above range limits the fifth lens to have appropriate positive refractive power, which is beneficial to the convergence of light rays. The fifth lens with positive refractive power and the sixth lens with negative refractive power cooperate to adjust the optical path difference between different fields of view, improve the resolution, are beneficial to the smooth entry of light rays into the rear lens, and can further reduce the field curvature and correct the off-axis point aberration 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: -1.1 < f6 / f < -0.9. Satisfying the above range limits the sixth lens to have appropriate negative refractive power, can diverge the light rays emitted by the fifth lens, make the light rays of the edge field of view have an upward trend, are beneficial to the image points on the imaging surface away from the optical axis, are beneficial to the realization of the effect of matching a large chip, can effectively eliminate aberration, and improve the resolution of the optical lens.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.7 < f7 / f < 1.9. Satisfying the above range limits the seventh lens to have positive refractive power, is beneficial to the convergence of light rays, makes the light rays smoothly transition to the rear, reduces the height of the light rays incident to the rear, slows down the upward trend of the light rays, avoids the loss of light energy caused by the large field of view light rays reaching the imaging surface and the main light ray angle of the chip being too large, is beneficial to improving the illumination of the edge field of view, and is beneficial to realizing a short total optical length.

[0072] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.8 < f1 / f2 < -0.6. Satisfying the above range controls the refractive powers of the first lens and the second lens to be positive and negative, is beneficial to balancing aberration and improving resolution; further, controlling the ratio of the two within the conditional range is beneficial to the smoothness of the light ray trend and reduces the sensitivity.

[0073] In some embodiments, the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface of the second lens satisfy: -3.1 < (R3-R4) / (R3+R4) < -1.8. Satisfying the above range can compress the height of the light rays incident through the object side surface, so that the light rays exiting through the image side surface are further converged, so that the divergent light rays smoothly enter the lens behind, further so that the light ray trend is smoothly transitioned, which is beneficial to reduce the front aperture of the lens.

[0074] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the sagittal height Sag1 of the object side surface of the first lens satisfy: 203 < R1 / Sag1 < 426. Satisfying the above range controls the ratio of the sagittal height of the object side surface and the radius of curvature, which is beneficial to reduce the angle between the edge field of view light and the object side surface of the first lens, and improve the overall edge relative luminance of the lens.

[0075] In some embodiments, the air gap CT34 of the third lens and the fourth lens on the optical axis and the total optical length TTL of the optical lens satisfy: 0.2 < CT34 / TTL < 0.3. Satisfying the above range controls the air gap between the third lens and the fourth lens, which is beneficial to smoothly transition the light rays under the premise of miniaturization and improve the imaging quality; further, controlling the air gap to be larger can further reduce the sensitivity of the optical lens.

[0076] In some embodiments, the optical lens satisfies the following conditional expressions: 6.5mm < f < 8mm; 60° < FOV < 75°; 4mm < EPD < 5mm; 35mm < TTL < 39mm; 1.6 < Fno < 1.8; 8mm < IH < 9mm; 27° < CRA < 28°; 4.5mm < BFL < 5.5mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray incidence angle at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Satisfying the above range, the optical lens has one or more advantages such as large target surface, large aperture, long focal length, etc.

[0077] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the low dispersion characteristic of the glass itself can effectively correct the geometric chromatic aberration of the optical system. The optical lens provided by the present application can adopt a full-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0078] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt a spherical lens or an aspherical lens. Compared with a spherical structure, an aspherical structure can effectively reduce aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens of the present application adopt a spherical lens, and the seventh lens adopts an aspherical lens.

[0079] In various embodiments of the present application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[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 B, C, D, E, and F are the fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients, respectively.

[0082] The present application is further described in the following embodiments. In various embodiments, 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 present application, but the embodiments of the present 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 present application should be regarded as equivalent replacement modes, and are included in the protection scope of the present application.

[0083] Embodiment 1

[0084] Please refer to Figure 1 , which is a structural schematic diagram of an optical lens 100 provided in Embodiment 1 of the present application. The optical lens 100 includes, in order from the object side to the imaging surface along the optical axis, a first lens L1, a second lens L2, a third lens L3, a diaphragm ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

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

[0086] The second lens L2 has a positive focal power, the object side surface S3 thereof is a convex surface, and the image side surface S4 thereof is a convex surface.

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

[0088] The fourth lens L4 has positive refractive power, the object side S7 is a convex surface, and the image side S8 is a convex surface;

[0089] The fifth lens L5 has positive refractive power, the object side S9 is a convex surface, and the image side S10 is a concave surface;

[0090] The sixth lens L6 has negative refractive power, the object side S10 is a convex surface, and the image side S11 is a concave surface;

[0091] The fifth lens L5 and the sixth lens L6 constitute a cemented lens group, that is, the cemented surface of the image side of the fifth lens L5 and the object side of the sixth lens L6 is S10;

[0092] The seventh lens L7 has positive refractive power, the object side S12 is a convex surface, and the image side S13 is a concave surface;

[0093] The object side S14 and the image side S15 of the filter G1 are both flat surfaces;

[0094] The object side S16 and the image side S17 of the protective glass G2 are both flat surfaces;

[0095] The imaging surface S18 is a flat surface.

[0096] The seventh lens L7 is a glass aspheric lens, and the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are glass spherical lenses.

[0097] The related parameters of the lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0098] Table 1-1

[0099]

[0100] The surface type parameters of the aspheric lenses of the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0101] Table 1-2

[0102] Face number K B C D E F S12 -8.21E-01 7.66E-04 4.50E-06 1.75E-06 -9.53E-08 3.62E-09 S13 5.95E+00 8.41E-04 -2.61E-06 2.33E-06 -1.72E-07 7.58E-09

[0103] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve, and the MTF curve of the optical lens 100 are shown in Figure 2 , Figure 3 , Figure 4 respectively.

[0104] Figure 2The field curvature curve 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 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, which shows that the optical lens can well correct the field curvature.

[0105] Figure 3 The F-Tan(Theta) distortion curve of embodiment 1 is shown, which represents the distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the distortion of the optical lens is controlled within-15%~0, which shows that the optical lens can well correct the distortion.

[0106] Figure 4 The MTF (modulation transfer function) curve of embodiment 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of the embodiment is above 0.6 in the full field of view, and in the range of 0~120lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0107] Embodiment 2

[0108] Please refer to Figure 5 , which is a structural schematic diagram of the optical lens 200 provided in embodiment 2 of the present application. Compared with embodiment 1, the main difference is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0109] The related parameters of each lens in the optical lens 200 in embodiment 2 are shown in table 2-1.

[0110] Table 2-1

[0111]

[0112]

[0113] The surface type parameters of the aspherical lens of the optical lens 200 in embodiment 2 are shown in table 2-2.

[0114] Table 2-2

[0115] Face number K B C D E F S12 -8.10E-01 7.76E-04 3.45E-06 1.77E-06 -9.53E-08 3.57E-09 S13 5.81E+00 8.79E-04 -4.92E-06 2.34E-06 -1.60E-07 6.37E-09

[0116] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens 200 are respectively as followsFigure 6 、 Figure 7 、 Figure 8 .

[0117] As can be seen from Figure 6 , the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.03mm, which shows that the optical lens can well correct the field curvature.

[0118] As can be seen from Figure 7 , the distortion of the optical lens is controlled within-12%~0, which shows that the optical lens can well correct the distortion.

[0119] As can be seen from Figure 8 , the MTF value of the embodiment is above 0.6 in the full field of view, and in the range of 0~120lp / 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.

[0120] Embodiment 3

[0121] Please refer to Figure 9 , which is a structural schematic diagram of the optical lens 300 provided in the embodiment 3 of the present application, and the main difference between the embodiment and the embodiment 1 is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0122] The related parameters of each lens in the optical lens 300 in the embodiment 3 are shown in Table 3-1.

[0123] Table 3-1

[0124]

[0125]

[0126] The surface type parameters of the aspherical lens of the optical lens 300 in the embodiment 3 are shown in Table 3-2.

[0127] Table 3-2

[0128] Face number K B C D E F S12 -8.21E-01 7.66E-04 5.24E-06 1.73E-06 -9.62E-08 3.76E-09 S13 6.12E+00 8.36E-04 -2.51E-06 2.36E-06 -1.82E-07 7.78E-09

[0129] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens 300 are respectively shown in Figure 10 、 Figure 11 、 Figure 12 .

[0130] As can be seen from Figure 10 , the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.03mm, which shows that the optical lens can well correct the field curvature.

[0131] From Figure 11 it can be seen that the distortion of the optical lens is controlled within-15%~0, which shows that the optical lens can well correct the distortion.

[0132] From Figure 12 it can be seen that the MTF value of the embodiment is above 0.6 in the full field of view, and in the range of 0~120lp / 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.

[0133] Embodiment 4

[0134] Please refer to Figure 13 , which is a structural schematic diagram of the optical lens 400 provided in embodiment 4 of the present application, and the main difference between the embodiment and embodiment 1 is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0135] The related parameters of each lens in the optical lens 400 in embodiment 4 are shown in Table 4-1.

[0136] Table 4-1

[0137]

[0138] The surface type parameters of the aspherical lens of the optical lens 400 in embodiment 4 are shown in Table 4-2.

[0139] Table 4-2

[0140] Face number K B C D E F S12 -8.26E-01 7.61E-04 6.25E-06 1.70E-06 -9.78E-08 3.92E-09 S13 6.43E+00 8.19E-04 -1.75E-06 2.40E-06 -1.95E-07 8.11E-09

[0141] In this embodiment, the field curvature curve, F-Tan(Theta) distortion curve and MTF curve of the optical lens 400 are shown in Figure 14 , Figure 15 , Figure 16 respectively.

[0142] From Figure 14 it can be seen that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.03mm, which shows that the optical lens can well correct the field curvature.

[0143] From Figure 15 it can be seen that the distortion of the optical lens is controlled within-15%~0, which shows that the optical lens can well correct the distortion.

[0144] From Figure 16It can be seen that the MTF value of the embodiment is above 0.6 in the full field of view, and in the range of 0-120 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.

[0145] Please refer to Table 5 for the optical characteristics 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 corresponding to the maximum field of view, the chief ray angle of incidence CRA at the maximum image height, the maximum field of view FOV of the optical lens, and the numerical value corresponding to each conditional expression in each embodiment.

[0146] Table 5

[0147]

[0148]

[0149] In summary of the above embodiments, the optical lens provided by the present application adopts seven lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as large target surface, large aperture, high imaging quality, etc.

[0150] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present 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.

[0151] The above-described embodiments only express several embodiments of the present application, which are described in a more specific and detailed manner, but should not be understood as limiting the scope of the patent of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection 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 surface along the optical axis, sequentially comprise: a first lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a concave surface; a second lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a third lens with negative 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, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fifth lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a sixth 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 seventh lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; wherein the effective focal length f of the optical lens and the image side surface curvature radius R6 of the third lens satisfy -2.8 < R6 / f < -2.4; the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy 1.16 < (R1-R2) / (R1+R2) < 1.27; the object side surface curvature radius R13 of the seventh lens and the image side surface curvature radius R14 of the seventh lens satisfy -0.35 < (R13-R14) / (R13+R14) < -0.2; 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 1.85 < IH / EPD < 2.

1.

2. The optical lens of claim 1, wherein, The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy 4.5 < TTL / f < 5.

5.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens, the maximum field angle FOV of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 0.85 < (IH / 2) / (f*tan(FOV / 2)) < 0.

92.

4. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy -31 < f3 / f < -23.

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

3.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy 0.6 < BFL / f < 0.

8.

7. The optical lens of claim 1, wherein, The effective focal length f of the optical lens, the radian value θ of the maximum half field angle of the optical lens and the object side surface half light entrance radius d1 of the first lens satisfy 0.5 < f*θ / d1 < 0.

7.

8. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy -1.95 < f1 / f < -1.7; the focal length f1 of the first lens and the focal length f2 of the second lens satisfy -0.8 < f1 / f2 < -0.

6.

9. The optical lens of claim 1, wherein, The object side surface curvature radius R3 of the second lens and the image side surface curvature radius R4 of the second lens satisfy -3.1 < (R3-R4) / (R3+R4) < -1.

8.

10. The optical lens of claim 1, wherein, The object side surface curvature radius R1 of the first lens and the object side surface half light entrance sag height Sag1 of the first lens satisfy 203 < R1 / Sag1 < 426.

Images