Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses in sequence along an optical axis from an object side to an imaging surface, and the seven lenses comprise: a first lens with negative optical power, wherein the object side surface is a convex surface and the image side surface is a concave surface; a second lens with negative optical power, wherein the object side surface is a convex surface and the image side surface is a concave surface; a third lens with positive optical power, wherein the object side surface is a concave surface and the image side surface is a convex surface; a fourth lens with positive optical power, wherein the object side surface is a convex surface and the image side surface is a convex surface; a fifth lens with negative optical power, wherein the object side surface is a concave surface and the image side surface is a convex surface; a sixth lens with negative optical power, wherein the object side surface is a concave surface and the image side surface is a concave surface; and a seventh lens with positive optical power, wherein the object side surface is a convex surface and the image side surface is a convex surface. The optical lens provided by the application improves the imaging quality of the optical lens, reduces aberration and improves the imaging quality of the optical lens through reasonable configuration of the surface shape of each lens and reasonable matching of optical power.

Description

TECHNICAL FIELD

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

[0002] With the continuous improvement of people's requirements for driving experience, vehicle application type optical lenses are used more and more in intelligent driving, and vehicle optical lenses are playing an increasingly important role in the automobile industry.

[0003] Advanced Driver Assistance System (ADAS) plays an important role in intelligent driving. It collects environmental information through various lenses combined with sensors to ensure the safety of drivers. The surround view lens is used to shoot the environment around the vehicle. The pictures captured by multiple cameras will be transmitted to the vehicle processor for real-time processing. The processor will correct, splice and fuse these pictures appropriately to generate a continuous, seamless and full-360-degree surround view image. The surround view lens generally uses a wide-angle lens, which has large distortion and poor imaging quality, making it difficult to meet user needs. Therefore, it is necessary to develop an optical lens with good imaging effect. SUMMARY

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

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

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

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

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

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

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

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

[0012] The seventh lens has positive focal power, the object side surface is convex, and the image side surface is convex;

[0013] The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -5.2 < f1 / f < -4.5.

[0014] Further preferably, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 35° / mm < FOV / IH < 36° / mm.

[0015] Further preferably, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 10 < TTL / f < 11.

[0016] Further preferably, the back focal length BFL of the optical lens and the total track length TTL of the optical lens satisfy: 0.18 < BFL / TTL < 0.19.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2300 < f5 / f < -1400.

[0018] Further preferably, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -4.6 < R11 / R12 < -4.4.

[0019] Further preferably, the center thickness CT3 of the third lens and the center thickness CT4 of the fourth lens satisfy: 3.4 < CT3 / CT4 < 3.9.

[0020] Further preferably, the half sagittal height SAG71 of the object side surface of the seventh lens, the half sagittal height SAG72 of the image side surface of the seventh lens and the center thickness CT7 of the seventh lens satisfy: -0.7 < (SAG72-SAG71) / CT7 < -0.6.

[0021] Further preferably, the real image height IH corresponding to the maximum field of view FOV of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 5.5 < IH / EPD < 7.

[0022] Further preferably, the real image height IH corresponding to the maximum field of view FOV of the optical lens, the effective focal length f of the optical lens and the radian value θ of the maximum half field of view of the optical lens satisfy: 0.99 < (IH / 2) / (f x θ) < 1.

[0023] 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 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 of large aperture, short focus, super large field of view, small distortion, high imaging quality and the like. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0025] Figure 1 Structure diagram of the optical lens in embodiment 1 of the present application.

[0026] Figure 2 Field curvature curve of the optical lens in embodiment 1 of the present application.

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

[0028] Figure 4 Axial aberration curve of the optical lens in embodiment 1 of the present application.

[0029] Figure 5 Vignetting curve of the optical lens in embodiment 1 of the present application.

[0030] Figure 6 Structure diagram of the optical lens in embodiment 2 of the present application.

[0031] Figure 7 Field curvature curve of the optical lens in embodiment 2 of the present application.

[0032] Figure 8 F-Theta distortion curve of the optical lens in embodiment 2 of the present application.

[0033] Figure 9 Axial aberration curve of the optical lens in embodiment 2 of the present application.

[0034] Figure 10 Vignetting curve of the optical lens in embodiment 2 of the present application.

[0035] Figure 11 Structure diagram of the optical lens in embodiment 3 of the present application.

[0036] Figure 12 Field curvature curve of the optical lens in embodiment 3 of the present application.

[0037] Figure 13 F-Theta distortion curve of the optical lens in embodiment 3 of the present application.

[0038] Figure 14 Axial aberration curve of the optical lens in embodiment 3 of the present application.

[0039] Figure 15 Vignetting curve of the optical lens in embodiment 3 of the present application.

[0040] The following detailed description will further explain the present application with reference to the accompanying drawings. DETAILED DESCRIPTION

[0041] For a better understanding of the present application, various aspects of the present application will be described in relation to the annexed drawings. It is stressed that these descriptions are only illustrative of embodiments of the present application and are not meant to limit the scope of the present application in any way. Throughout the present description, like reference numerals are used to refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0042] It is noted that, in this specification, the terms first, second, third, etc. are used merely to distinguish one feature from another, without implying any limitation on the features. Thus, the first lens discussed below can also be referred to as a second lens or a third lens, without departing from the teachings of the present application.

[0043] 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.

[0044] In this specification, 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 image plane is referred to as the image side surface of the lens.

[0045] It is also to be understood that the use of the terms "including", "comprising", "having" and / or "containing" when used in this specification, particularly in the claims, means that there are no restrictions on the presence of one or more other features, elements, components, and / or combinations thereof. In addition, the use of the term "at least one" when used in this specification, particularly in the claims, means that there is one or more of the listed features, elements, components, and / or combinations thereof. Furthermore, the use of the term "about" when used in this specification, particularly in the claims, means that there are no restrictions on the values of the elements, and that the values of the elements can vary by more than 10% of the value. In addition, when describing the embodiments of the present application, the use of "may" means that one or more embodiments of the present application. Also, the term "exemplary" is intended to mean an example or illustration.

[0046] 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 overly idealized or formal sense unless expressly so defined herein.

[0047] 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.

[0048] The optical lens provided by the embodiment of the present application comprises seven lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface and include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens.

[0049] In some embodiments, the first lens can have a negative focal power, the object side surface of which is convex, and the image side surface of which is concave. The second lens can have a negative focal power, the object side surface of which is convex, and the image side surface of which is concave. The third lens can have a positive focal power, the object side surface of which is concave, and the image side surface of which is convex. The fourth lens can have a positive focal power, the object side surface of which is convex, and the image side surface of which is convex. The fifth lens can have a negative focal power, the object side surface of which is concave, and the image side surface of which is convex. The sixth lens can have a negative focal power, the object side surface of which is concave, and the image side surface of which is concave. The seventh lens can have a positive focal power, the object side surface of which is convex, and the image side surface of which is convex.

[0050] 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.

[0051] In some embodiments, the optical lens can further comprise a filter, which is arranged between the seventh lens and the imaging surface. The filter is used to filter out the interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting the normal imaging.

[0052] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -5.2 < f1 / f < -4.5. By satisfying the above condition, the first lens has an appropriate negative focal length, which is beneficial to expand the field of view angle of the optical lens.

[0053] In some embodiments, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 35° / mm<FOV / IH<36° / mm. Satisfying the above condition, the optical lens has a large field of view, and the optical lens has good optical performance and can capture details of the object well.

[0054] In some embodiments, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 10<TTL / f<11. Satisfying the above condition, the length of the lens can be effectively limited, and the miniaturization of the optical lens is facilitated.

[0055] In some embodiments, the back focal length BFL of the optical lens and the total track length TTL of the optical lens satisfy: 0.18<BFL / TTL<0.19. Satisfying the above condition, the ratio of the back focal length of the optical lens to the total track length of the optical lens is reasonably configured, which is conducive to the short back focus of the optical lens, and in the case of ensuring sufficient space for installation and focusing of optical elements, the miniaturization of the optical lens is facilitated.

[0056] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2300<f5 / f<-1400. Satisfying the above condition, by reasonably setting the focal length of the fifth lens, the smooth transition of light is facilitated, the correction of astigmatism and field curvature is facilitated, the imaging quality of the optical lens is improved, and the stability of the optical system is ensured.

[0057] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -4.6<R11 / R12<-4.4. Satisfying the above condition, the sixth lens is a double-concave lens, and the radius of curvature of the sixth lens is reasonably set, which can correct the aberration of the optical lens and reduce the tolerance sensitivity of the optical lens.

[0058] In some embodiments, the center thickness CT3 of the third lens and the center thickness CT4 of the fourth lens satisfy: 3.4<CT3 / CT4<3.9. Satisfying the above condition, the ratio of the thickness of the third lens on the optical axis to the thickness of the fourth lens on the optical axis is reasonably configured, the third lens and the fourth lens can regulate each other, and the miniaturization feature of the optical system is maintained.

[0059] In some embodiments, the half-aperture sagittal height of the object-side surface of the seventh lens SAG71, the half-aperture sagittal height of the image-side surface of the seventh lens SAG72, and the center thickness of the seventh lens CT7 satisfy: -0.7 < (SAG72-SAG71) / CT7 < -0.6. By satisfying the above condition, by controlling the height difference between the sagittal heights of the image-side surface and the object-side surface of the seventh lens and the center thickness of the seventh lens, the coma of the off-axis field of view is corrected, and the imaging quality of the optical lens off-axis field of view is improved.

[0060] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 5.5 < IH / EPD < 7. By satisfying the above range, the optical lens can meet the requirements of large image surface while also meeting the requirements of sufficient image surface brightness in the edge field of view, preventing the occurrence of dark corner phenomenon, thereby improving the imaging quality.

[0061] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view angle of the optical lens satisfy: 0.99 < (IH / 2) / (f x θ) < 1. By satisfying the above condition, the lens has a smaller distortion value and can provide high-definition imaging effect.

[0062] In some embodiments, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens, and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 57° < (f x FOV) / IH < 58°. By satisfying the above condition, by reasonably limiting the relationship between the focal length, the field of view angle, and the image height of the optical lens, the balance between the large field of view angle and the large target surface imaging of the optical lens is achieved, better meeting the use requirements of the vehicle-mounted surround view camera.

[0063] 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 of the optical lens satisfy: 3.4 < IH / f < 3.5. By satisfying the above condition, a super large field of view angle and imaging range can be achieved, which can ensure the depth of field of the optical lens while achieving large image surface characteristics, thereby improving the imaging quality of the optical system.

[0064] In some embodiments, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 2.9 < TTL / IH < 3.1. By satisfying the above condition, the miniaturization of the lens can be better achieved, while ensuring that the lens has a larger image surface under the condition of the same total length, which can match a larger size imaging chip to achieve high-definition imaging.

[0065] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.2 < f2 / f < -3. The second lens also adopts a negative lens to further diverge the light rays and improve the field of view of the imaging system when the above condition is satisfied.

[0066] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 4.3 < f3 / f < 4.5; and the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 2.3 < f4 / f < 2.4. The third and fourth lenses converge the front-end incident light rays, which is conducive to correcting the aberration and edge field distortion caused by the front-end lens group, so that the lens has smaller distortion and can provide high-definition imaging effect.

[0067] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.7 < f6 / f < -1.6. The sixth lens has an appropriate negative focal length, which is conducive to further increasing the imaging area of the optical lens and balancing various aberrations generated by the front group of lenses to improve the imaging quality of the optical lens.

[0068] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.9 < f7 / f < 2. The seventh lens satisfies the above condition, which helps to reasonably collect light, ensure the light quantity, and improve the relative luminance, so that the luminance at the image plane of the optical lens is improved.

[0069] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 100° < FOV / Fno < 120°. The above condition is conducive to improving the light quantity of the lens, so that the lens can also provide high-definition imaging in a dark environment.

[0070] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 1.8 < BFL / f < 2. The above range is conducive to balancing the optical back focal length length between good imaging quality and easy assembly, so as to ensure the imaging quality of the optical lens, avoid interference between the lens and other elements, and reduce the assembly process difficulty of the camera module.

[0071] In some embodiments, the object side surface radius of curvature R1 of the first lens and the image side surface radius of curvature R2 of the first lens satisfy: 3 < R1 / R2 < 3.5. The above condition can reasonably set the surface type of the first lens and enhance the light collecting ability of the first lens, so as to realize an ultra-large field of view.

[0072] 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: -1 < R13 / R14 < -0.9. Satisfying the above range, the surface shape of the seventh lens is reasonably limited, which helps the light rays to be accurately focused on the imaging plane, and improves the definition and uniformity of brightness of the imaging.

[0073] In some embodiments, the object-side surface curvature radius R5 of the third lens and the image-side surface curvature radius R6 of the third lens satisfy: 1.4 < (R5+R6) / (R5-R6) < 1.7. Satisfying the above range, the light ray trend can be more stable; at the same time, coma and field curvature can be corrected, the flatness of the imaging is improved, and the imaging quality of the optical lens is improved.

[0074] In some embodiments, the object-side surface curvature radius R11 of the sixth lens and the image-side surface curvature radius R12 of the sixth lens satisfy: 0.6 < (R11+R12) / (R11-R12) < 0.7. Satisfying the above range, the object-side surface curvature radius and the image-side surface curvature radius of the sixth lens are reasonably controlled, thereby being conducive to controlling the shape of the sixth lens, correcting the aberration generated by itself, and improving the imaging quality.

[0075] 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: -0.1 < (R13+R14) / (R13-R14) < 0. Satisfying the above range, the shape of the object-side surface and the image-side surface of the seventh lens is reasonably limited, which can control the seventh lens to have a proper surface shape, and is helpful for controlling the light ray trend of the edge field of view and improving the imaging quality of the edge field of view.

[0076] In some embodiments, the object-side surface curvature radius R11 of the sixth lens and the effective focal length f of the optical lens satisfy: -6.2 < R11 / f < -6. Satisfying the above range, the sixth lens can have a proper surface shape, which is conducive to balancing the astigmatism and field curvature of the optical lens and improving the imaging quality of the optical lens.

[0077] In some embodiments, the focal length f1 of the first lens and the focal length f7 of the seventh lens satisfy: -2.7 < f1 / f7 < -2.3. Satisfying the above condition, by reasonably setting the focal length relationship of the first and last lenses in the lens, the area of the light entering the imaging plane is increased while ensuring that as many light rays as possible enter the system, which is conducive to realizing large image plane imaging of the lens, and at the same time, the light amount is increased, and the relative luminance of the system is improved.

[0078] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.5 < ∑CT / TTL < 0.6. Satisfying the above condition, the total length of the optical lens can be effectively compressed.

[0079] In some embodiments, the interval CT56 of the fifth lens and the sixth lens on the optical axis, the interval CT67 of the sixth lens and the seventh lens on the optical axis, and the central thickness CT6 of the sixth lens satisfy: 0.3<(CT56+CT67) / CT6<0.35. Satisfying the above condition, the size of the interval between the fifth lens, the sixth lens and the seventh lens and the central thickness of the sixth lens are reasonably arranged, which is conducive to the miniaturization of the system.

[0080] In some embodiments, the central thickness CT3 of the third lens and the edge thickness ET3 of the third lens satisfy: 0.95<CT3 / ET3<1. By making the optical system satisfy the above relationship, the lens processing and molding are facilitated, the assembly difficulty is reduced, and the field curvature of the system can be effectively corrected.

[0081] In some embodiments, the object side half-diameter sagittal height SAG61 of the sixth lens, the image side half-diameter sagittal height SAG62 of the sixth lens, and the central thickness CT6 of the sixth lens satisfy: -1.7<(SAG61-SAG62) / CT6<-1.6. Satisfying the above condition, by controlling the height difference between the sagittal heights of the image side and the object side of the sixth lens and the central thickness of the sixth lens, the shape of the sixth lens can be constrained, which is conducive to the design and processing of the sixth lens structure, the aberration of each field of view can be corrected respectively, and the imaging quality of the optical lens can be improved.

[0082] In some embodiments, the object side half-diameter DM11 of the first lens and the image side half-diameter DM72 of the seventh lens satisfy: 3<DM11 / DM72<3.5. Satisfying the above condition, while ensuring that the light enters the system in a large range, the aperture size of the lens is effectively reduced, which is conducive to the balance of the field of view and the aperture of the lens.

[0083] In some embodiments, the optical lens satisfies the condition: 16mm<TTL<18mm, 1.6mm<f<1.7mm, 195°<FOV<205°, 5.5mm<IH<5.8mm, 1.6<Fno<2, wherein TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, IH represents the image height corresponding to the maximum field of view angle of the optical lens, and Fno represents the aperture value of the optical lens. Satisfying the above conditions, the optical lens provided in the embodiments of the present application at least has the following characteristics: a small total optical length; a short focal length and a wide angle, the depth of field of the short focal length lens is relatively deep, and the subject in front and back can remain relatively clear; a super large field of view angle, which provides a wider shooting field of view for the vehicle-mounted surround view lens and other application scenarios, and takes more image information; a large imaging surface, which can match a large size chip to realize high-definition imaging; and a large aperture, which can realize high-definition imaging even in a complex light environment.

[0084] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristics of the glass itself. The first lens and the fourth lens in the optical lens provided by the present application can adopt glass material, and the second lens, the third lens, the fifth lens, the sixth lens and the seventh lens can adopt plastic material. The adoption of the glass-plastic hybrid structure can effectively reduce the cost, correct the aberration, reduce the volume, improve the thermal stability and provide an optical lens product with higher performance-price ratio.

[0085] 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 the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses and better realizing the miniaturization of the lens. More specifically, the first lens and the fourth lens in the present application adopt a spherical lens, and the second lens, the third lens, the fifth lens, the sixth lens and the seventh lens adopt an aspherical lens.

[0086] 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:

[0087] ;

[0088] 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.

[0089] The present application will be 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 all are included in the protection scope of the present application.

[0090] Embodiment 1

[0091] Please refer to Figure 1Figure 1 shows a structural schematic diagram of an optical lens provided in Embodiment 1 of the present application, which comprises, along an optical axis from an object side to an imaging surface, a first lens L1, a second lens L2, a third lens L3, a stop ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0092] The first lens L1 has a negative focal power, and its object side S1 is a convex surface and its image side S2 is a concave surface.

[0093] The second lens L2 has a negative focal power, and its object side S3 is a convex surface and its image side S4 is a concave surface.

[0094] The third lens L3 has a positive focal power, and its object side S5 is a concave surface and its image side S6 is a convex surface.

[0095] The fourth lens L4 has a positive focal power, and its object side S7 is a convex surface and its image side S8 is a convex surface.

[0096] The fifth lens L5 has a negative focal power, and its object side S9 is a concave surface and its image side S10 is a convex surface.

[0097] The sixth lens L6 has a negative focal power, and its object side S11 is a concave surface and its image side S12 is a concave surface.

[0098] The seventh lens L7 has a positive focal power, and its object side S13 is a convex surface and its image side S14 is a convex surface.

[0099] The object side S15 and the image side S16 of the filter G1 are both flat surfaces.

[0100] The imaging surface S17 is a flat surface.

[0101] The first lens L1 and the fourth lens L4 are glass spherical lenses, and the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are plastic aspherical lenses.

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

[0106] Table 1-2

[0107]

[0108] In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve and the transverse chromatic aberration curve of the optical lens are shown in Figs. 1-4, 5-8, 9-12 and 13-16, respectively. Figure 2 , Figure 3 , Figure 4 , Figure 5

[0109] Figure 2 Fig. 1 shows the field curvature curve of Example 1, which represents the curvature of light rays on the sagittal image plane and the tangential image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the field curvature of the sagittal image plane and the tangential image plane is controlled within -0.15mm~0.05mm, which indicates that the optical lens can well correct the field curvature.

[0110] Figure 3 Fig. 5 shows the F-Theta distortion curve of Example 1, which represents the F-Theta distortion of light rays at different image heights on the imaging plane, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within -1.2%~3%, which indicates that the optical lens can well correct the distortion.

[0111] Figure 4 Fig. 9 shows the axial aberration curve of Example 1, which represents the axial aberration of each wavelength on the optical axis at the imaging plane, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within -0.02mm~0.03mm, which indicates that the optical lens can well correct the axial aberration.

[0112] Figure 5 Fig. 13 shows the transverse chromatic aberration curve of Example 1, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555μm) at different image heights on the imaging plane, the horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. As can be seen from the figure, the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -4μm~6μm, which indicates that the optical lens can well correct the chromatic aberration.

[0113] Example 2

[0114] Please refer to Fig. 2, which shows the structural schematic diagram of the optical lens provided in Example 2 of the present application. Compared with Example 1, the difference between the present embodiment and Example 1 is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different. Figure 6 The related parameters of each lens in the optical lens in Example 2 are shown in Table 2-1.

[0115]

[0116] ​​Table 2-1

[0117]

[0118] The surface parameters of the aspherical lens of the optical lens in Example 2 are shown in Table 2-2.

[0119] Table 2-2

[0120]

[0121] In this embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, and the transverse chromatic aberration curve of the optical lens are shown in FIGS. 2-1, 2-2, 2-3, and 2-4, respectively. Figure 7 、 Figure 8 、 Figure 9 、 Figure 10

[0122] Figure 7 The field curvature curve of Example 2 is shown, which represents the curvature of light rays on the sagittal image surface and the tangential 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 sagittal image surface and the tangential image surface is controlled within -0.15 mm~0.05 mm, which shows that the optical lens can well correct the field curvature.

[0123] Figure 8 The F-Theta distortion curve of Example 2 is shown, which represents the F-Theta distortion of light rays at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within -0.6%~3%, which shows that the optical lens can well correct the distortion.

[0124] Figure 9 The axial aberration curve of Example 2 is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within -0.02 mm~0.01 mm, which shows that the optical lens can well correct the axial aberration.

[0125] Figure 10 The transverse chromatic aberration curve of Example 2 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface, the horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. As can be seen from the figure, the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -4 μm~6 μm, which shows that the optical lens can well correct the chromatic aberration.

[0126] Example 3​

[0127] Referring to Figure 11 , a structural schematic diagram of an optical lens provided in Embodiment 3 of the present application is shown, and the difference between this 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.

[0128] The related parameters of each lens in the optical lens in Embodiment 3 are shown in Table 3-1.

[0129] Table 3-1

[0130]

[0131] The surface type parameters of the aspherical lens of the optical lens in Embodiment 3 are shown in Table 3-2.

[0132] Table 3-2

[0133]

[0134] In this embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve and the transverse aberration curve of the optical lens are shown in Figure 12 , Figure 13 , Figure 14 , Figure 15 respectively.

[0135] Figure 12 The field curvature curve of Embodiment 3 is shown, which represents the curvature of 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 -0.1mm~0.1mm, which shows that the optical lens can well correct the field curvature.

[0136] Figure 13 The F-Theta distortion curve of Embodiment 3 is shown, which represents the F-Theta distortion of the light rays at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within -0.6%~3%, which shows that the optical lens can well correct the distortion.

[0137] Figure 14 The axial aberration curve of Embodiment 3 is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within -0.01mm~0.02mm, which shows that the optical lens can well correct the axial aberration.

[0138] Figure 15 A curve diagram of the sagittal chromatic aberration of Example 3 is shown, which represents the chromatic aberration of each wavelength at different image heights on the imaging plane relative to the central wavelength (0.555 μm), the horizontal axis represents the sagittal chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the diagram, the sagittal chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -4 μm ~ 6 μm, which indicates that the optical lens can correct chromatic aberration very well.

[0139] Referring to Table 4, the optical characteristics corresponding to each of the above examples are shown, including the effective focal length f, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view, the chief ray angle CRA at the maximum image height, the maximum field of view FOV, and the numerical value corresponding to each conditional expression in each example.

[0140] Table 4

[0141]

[0142] In summary of the above examples, 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 of large aperture, short focal length, super large field of view, small distortion, high imaging quality, etc.

[0143] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0144] 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 persons in the art, several modifications and improvements can be made without departing from the concept of the present application, which are all within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present application should be subject to the appended claims.

Claims

1. An optical lens, in total seven pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, the optical lens comprises in sequence: a first lens with negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens with negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a third lens with positive refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a fourth lens with positive refractive power, 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 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 sixth 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 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 convex surface; the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -5.2 < f1 / f < -4.5; the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 10 < TTL / f < 11.

2. The optical lens of claim 1, wherein, the maximum field of view angle FOV of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 35° / mm < FOV / IH < 36° / mm.

3. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.4 < IH / f < 3.

5.

4. The optical lens of claim 1, wherein, the back focal length BFL of the optical lens and the total track length TTL of the optical lens satisfy: 0.18 < BFL / TTL < 0.

19.

5. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2300 < f5 / f < -1400.

6. The optical lens of claim 1, wherein, the object side surface curvature radius R11 of the sixth lens and the image side surface curvature radius R12 of the sixth lens satisfy: -4.6 < R11 / R12 < -4.

4.

7. The optical lens of claim 1, wherein, the central thickness CT3 of the third lens and the central thickness CT4 of the fourth lens satisfy: 3.4 < CT3 / CT4 < 3.

9.

8. The optical lens of claim 1, wherein, the object side surface half entrance pupil height SAG71 of the seventh lens, the image side surface half entrance pupil height SAG72 of the seventh lens and the central thickness CT7 of the seventh lens satisfy: -0.7 < (SAG72-SAG71) / CT7 < -0.

6.

9. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 5.5 < IH / EPD < 7.

10. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens and the radian value θ of the maximum half field of view angle of the optical lens satisfy: 0.99 < (IH / 2) / (f x θ) < 1.

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