Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; and the image side surface of the seventh lens is a convex surface. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the aberration is reduced, the imaging quality of the optical lens is improved, and the lens has one or more advantages of ultra-wide angle, short total length, large aperture, high imaging quality and the like.

Description

Technical Field

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

[0002] In the field of modern sports video capture, high-performance portable optical systems are the core requirements. However, these traditional optical structures generally have problems such as a decline in imaging quality in low-light environments and insufficient dynamic range. At the same time, in order to improve the anti-shake performance, complex optical compensation mechanisms are often adopted, resulting in an increase in the volume and weight of the lens module, which not only restricts the adaptability of the device to extreme sports scenarios but also significantly increases the production and maintenance costs. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens having one or more advantages such as an ultra-wide angle, a short overall length, a large aperture, and high imaging quality.

[0004] The present invention provides an optical lens, which has a total of seven lenses, and sequentially includes, along the optical axis from the object side to the imaging surface: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a negative optical power, whose image side is concave; A third lens with a positive optical power, whose object side is convex and whose image side is concave; A fourth lens with a positive optical power, whose object side is concave and whose image side is convex; A fifth lens with a positive optical power, whose object side is convex and whose image side is convex; A sixth lens with a negative optical power, whose object side is concave and whose image side is concave; A seventh lens with a positive optical power, whose image side is convex; The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 50 < f3 / f < 130; The central thickness CT2 of the second lens on the optical axis and the central thickness CT3 of the third lens on the optical axis satisfy: 0.18 < CT2 / CT3 < 0.36.

[0005] Further preferably, the curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: 0.75 < R5 / R6 < 0.95.

[0006] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 3.6 < f4 / f < 4.3; the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: 1.9 < (R7 + R8) / (R7 - R8) < 2.1.

[0007] Further preferably, the sagittal height SAG11 of the object side surface of the first lens and the clear aperture diameter DM11 of the object side surface of the first lens satisfy: 0.16 < SAG11 / DM11 < 0.2.

[0008] Further preferably, the sagittal height SAG41 of the object side surface of the fourth lens and the clear aperture diameter DM41 of the object side surface of the fourth lens satisfy: -0.07 < SAG41 / DM41 < -0.05; the sagittal height SAG42 of the image side surface of the fourth lens and the clear aperture diameter DM42 of the image side surface of the fourth lens satisfy: -0.2 < SAG42 / DM42 < -0.15.

[0009] Further preferably, the maximum field of view FOV of the optical lens and the f-number Fno of the optical lens satisfy: 105° < FOV / Fno < 130°.

[0010] Further preferably, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5 < BFL / f < 1.8.

[0011] Further preferably, the edge thickness ET3 of the third lens and the central thickness CT3 of the third lens on the optical axis satisfy: 0.9 < ET3 / CT3 < 1.1.

[0012] Further preferably, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: 0.6 < f1 / f2 < 0.7.

[0013] Further preferably, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 8.5 < TTL / f < 11.

[0014] Compared with the prior art, the optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and enable the lens to have one or more advantages such as ultra-wide angle, short total length, large aperture, and high imaging quality. Description of the Drawings

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, where: Figure 1 It is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0016] Figure 2 It is an astigmatism curve graph of the optical lens in Embodiment 1 of the present invention.

[0017] Figure 3 It is an axial aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0018] Figure 4 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0019] Figure 5 It is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0020] Figure 6 It is an astigmatism curve graph of the optical lens in Embodiment 2 of the present invention.

[0021] Figure 7 It is an axial aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0022] Figure 8 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0023] Figure 9 It is a schematic structural diagram of the optical lens in Embodiment 3 of the present invention.

[0024] Figure 10 It is an astigmatism curve graph of the optical lens in Embodiment 3 of the present invention.

[0025] Figure 11 It is an axial aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0026] Figure 12 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0027] Figure 13 It is a schematic structural diagram of the optical lens in Embodiment 4 of the present invention.

[0028] Figure 14 It is an astigmatism curve graph of the optical lens in Embodiment 4 of the present invention.

[0029] Figure 15 It is an axial aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0030] Figure 16 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0031] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Detailed implementation manners

[0032] To better understand the present application, more detailed descriptions of various aspects of the present application will be made with reference to the accompanying 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.

[0033] It should be noted that in this specification, the expressions such as first, second, third, etc. are only used to distinguish one feature from another feature and do not represent any limitation on the feature. Therefore, without departing from the teachings of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0034] In the accompanying drawings, for the sake of convenience of illustration, the thickness, size and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0035] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object to be photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

[0036] It should also be understood that the terms "comprise", "comprising", "have", "include" and / or "including", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when an expression such as "at least one of..." appears after the list of listed features, it modifies the entire list of listed features rather than an individual element in the list. In addition, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". And the term "exemplary" is intended to refer to an example or illustration.

[0037] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in a common dictionary) should be interpreted as having a meaning 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.

[0038] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments may be combined with each other. The following will detail this application with reference to the drawings and in combination with the embodiments.

[0039] The optical lens provided by the embodiment of the present invention has a total of seven lenses. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0040] The first lens may have a negative focal power. Its object side surface is convex, and its image side surface is concave. The second lens may have a negative focal power. Its object side surface may be concave or convex, and its image side surface is concave. The third lens may have a positive focal power. Its object side surface is convex, and its image side surface is concave. The fourth lens may have a positive focal power. Its object side surface is concave, and its image side surface is convex. The fifth lens may have a positive focal power. Its object side surface is convex, and its image side surface is convex. The sixth lens may have a negative focal power. Its object side surface is concave, and its image side surface is concave. The seventh lens may have a positive focal power. Its object side surface may be concave or convex, and its image side surface is convex.

[0041] In some embodiments, the optical lens may further include a diaphragm. The diaphragm may be located between the fourth lens and the fifth lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image. When the diaphragm is located between the fourth lens and the fifth lens, it is convenient for the correction of diaphragm aberration.

[0042] In some embodiments, the optical lens may further include a filter. The filter is disposed between the seventh lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0043] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 50 < f3 / f < 130. By satisfying the above conditions and reasonably setting the focal length of the third lens, it is beneficial for the smooth transition of light rays, convenient for the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0044] In some embodiments, the central thickness CT2 of the second lens on the optical axis and the central thickness CT3 of the third lens on the optical axis satisfy: 0.18 < CT2 / CT3 < 0.36. Meeting the above conditions can reduce the assembly deformation and assembly difficulty of the lens while meeting the requirements of assembly stability, and at the same time make the structure of the lens more compact, which is conducive to realizing the miniaturization of the lens.

[0045] In some embodiments, the object-side curvature radius R5 of the third lens and the image-side curvature radius R6 of the third lens satisfy: 0.75 < R5 / R6 < 0.95. Meeting the above conditions is beneficial to controlling the shape of the third lens, correcting the aberration generated by itself, and improving the imaging quality.

[0046] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 3.6 < f4 / f < 4.3; the object-side curvature radius R7 of the fourth lens and the image-side curvature radius R8 of the fourth lens satisfy: 1.9 < (R7 + R8) / (R7 - R8) < 2.1. Meeting the above conditions, the fourth lens has an appropriate positive optical power and surface shape, avoiding the influence of too extreme shapes on the optical performance, being beneficial to slowing down the light turning trend and reducing the light height, making the light trend transition smoothly, and at the same time being beneficial to reducing the correction difficulty of spherical aberration and field curvature, and improving the imaging quality of the optical lens.

[0047] In some embodiments, the central thickness CT3 of the third lens on the optical axis and the sagittal height SAG32 of the image-side clear aperture radius of the third lens satisfy: 21 < CT3 / SAG32 < 35. Meeting the above conditions, by controlling the third lens to be extremely thick and the edge curvature to be extremely gentle, the spherical aberration of the large aperture can be reduced, and the marginal astigmatism can be significantly reduced.

[0048] In some embodiments, the sagittal height SAG11 of the object-side clear aperture radius of the first lens and the object-side clear aperture diameter DM11 of the first lens satisfy: 0.16 < SAG11 / DM11 < 0.2. Meeting the above conditions can avoid the object-side surface shape of the first lens from being too curved, reduce the processing difficulty of the first lens; and at the same time is also beneficial to the marginal light to be transmitted to the rear end of the optical lens, improving the imaging quality of the optical lens.

[0049] In some embodiments, the sagittal height SAG41 of the object-side clear aperture radius of the fourth lens and the object-side clear aperture diameter DM41 of the fourth lens satisfy: -0.07 < SAG41 / DM41 < -0.05; the sagittal height SAG42 of the image-side clear aperture radius of the fourth lens and the image-side clear aperture diameter DM42 of the fourth lens satisfy: -0.2 < SAG42 / DM42 < -0.15. Meeting the above conditions can limit the degree of central depression of the fourth lens and reduce the aberration correction difficulty of the marginal field of view.

[0050] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 105° < FOV / Fno < 130°. Meeting the above conditions limits the optical lens to have an appropriate field of view and aperture value, enabling it to collect light at a large angle and obtain good imaging quality.

[0051] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5 < BFL / f < 1.8. Meeting the above range is conducive to achieving a balance between obtaining good imaging quality and an optical back focal length that is easy to assemble. While ensuring the imaging quality of the optical lens, it avoids interference between the lens and other components and reduces the assembly process difficulty of the camera module.

[0052] In some embodiments, the edge thickness ET3 of the third lens and the central thickness CT3 of the third lens on the optical axis satisfy: 0.9 < ET3 / CT3 < 1.1. Meeting the above conditions, by controlling the ratio of the thickness on the optical axis to the edge thickness of the third lens, the high-order aberration generated by the optical lens can be effectively balanced, and it is also conducive to the field curvature adjustment of the lens, thereby improving the imaging quality of the optical lens.

[0053] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: 0.6 < f1 / f2 < 0.7. Meeting the above conditions, by reasonably setting the ratio of the focal lengths of the first lens and the second lens, while achieving a large field of view, the deflection degree of incident light within the large field of view can be reasonably balanced, reducing the sensitivity of the optical system, and at the same time reducing the difficulty of system distortion correction and improving the overall imaging quality.

[0054] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 8.5 < TTL / f < 11. Meeting the above conditions can reasonably control the overall length of the optical lens and the focal length of the optical lens, so that the optical lens has a reasonable focal length without causing the overall length of the optical lens to be too long, which is conducive to the miniaturization of the optical lens.

[0055] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV of the optical lens, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 60° < (f × FOV) / IH < 67°. Meeting the above range, by reasonably restricting the relationship between the focal length, field of view, and image height of the optical lens, it can be ensured that the optical lens has the characteristics of a large field of view, so that the optical lens has good optical performance and can capture the details of the object to be photographed well.

[0056] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -3.5 < f1 / f < -2.7. Meeting the above conditions, the first lens has an appropriate negative focal length, which is beneficial to expanding the field of view angle of the optical lens.

[0057] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -5 < f2 / f < -4. Meeting the above conditions, the second lens has an appropriate negative focal length, which can share the negative optical power at the front end of the optical lens, thus facilitating the avoidance of excessive light deflection caused by the over-concentration of the optical power of the first lens and reducing the difficulty of chromatic aberration correction of the optical lens.

[0058] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.8 < f5 / f < 2. Meeting the above conditions, the fifth lens has an appropriate positive focal length, which is beneficial to the smooth transition of light, facilitating the correction of astigmatism and field curvature, and improving the imaging quality of the optical lens.

[0059] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.8 < f6 / f < -1.6. Meeting the above conditions, the sixth lens has an appropriate negative focal length, which is beneficial to increasing the imaging area of the optical lens, while balancing various aberrations generated by the fifth lens and improving the imaging quality of the optical lens.

[0060] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 2.3 < f7 / f < 3. Meeting the above conditions, the seventh lens has a short focal length, which helps to collect light, ensure the light throughput, improve the relative illumination, and enhance the brightness of the optical lens at the image plane.

[0061] In some embodiments, the focal length f1 of the first lens and the focal length f7 of the seventh lens satisfy: -1.2 < f1 / f7 < -1. Meeting the above conditions, by reasonably setting the focal length relationship between the first and the last lenses in the lens, while ensuring that as much light as possible enters the system, the area of light entering the imaging plane is increased, which is beneficial to achieving large image plane imaging of the lens, while increasing the light input and improving the relative illumination of the system.

[0062] In some embodiments, the edge thickness CT4 of the fourth lens and the central thickness CT4 of the fourth lens on the optical axis satisfy: 0.8 < ET4 / CT4 < 0.9. Meeting the above conditions, the surface shape of the fourth lens can be reasonably controlled, making its surface shape have a small curvature. By slightly restricting the ratio of the edge thickness to the central thickness of the lens, the lens structure is easy to process, and the production cost is saved to a certain extent.

[0063] In some embodiments, the distance ET34 between the edge of the third lens and the edge of the fourth lens, the distance CT34 between the third lens and the fourth lens on the optical axis, and the total optical length TTL of the optical lens satisfy: 0.01 < (ET34 + CT34) / TTL < 0.03; the distance ET56 between the edge of the fifth lens and the edge of the sixth lens, and the distance ET67 between the edge of the sixth lens and the edge of the seventh lens and the total optical length TTL of the optical lens satisfy: 0.02 < (ET56 + ET67) / TTL < 0.04. Meeting the above ranges can reduce the edge distance between each lens, making the structure of the optical lens compact.

[0064] In some embodiments, the combined focal length f57 of the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 2.6 < f57 / f < 3.2. By satisfying the above relational expression, on the one hand, it is beneficial to control the height of the outgoing light beam of the optical system, so as to reduce the high-order aberration of the optical system and the outer diameter of the lens; on the other hand, it can correct the influence of the field curvature generated by the front lens group on the resolution.

[0065] In some embodiments, the optical lens satisfies the conditional formula: 9mm < TTL < 12mm, 1mm < f < 1.1mm, 190° < FOV < 200°, 3.2mm < IH < 3.4mm, 1.5 < Fno < 1.9, where 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 true image height corresponding to the maximum field of view angle of the optical lens, and Fno represents the aperture value of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least one or more advantages such as miniaturization, large field of view angle, and large aperture.

[0066] In some embodiments, the seven lenses in the optical lens can all be made of plastic lenses or adopt a structure with a combination of glass and plastic materials. Preferably, the optical lens of the present invention adopts a lens structure with a combination of seven glass and plastic materials, which can improve the thermal stability performance. Specifically, the first lens and the fourth lens can be made of glass lenses, and the second lens, the third lens, the fifth lens, the sixth lens and the seventh lens are all plastic lenses; adopting a glass-plastic hybrid structure can effectively reduce costs, correct aberrations, reduce volume, and provide an optical lens product with higher cost performance.

[0067] 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 be spherical lenses or aspherical lenses. 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, in the optical lens provided by the present invention, the first lens and the fourth lens are spherical lenses, and the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens can be aspherical lenses.

[0068] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equation: ; where z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, 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 conic coefficient, and B, C, D, E, F, G, H are the coefficients of the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order curved surfaces respectively.

[0069] The present invention will be further described in multiple embodiments below. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are partially different. For specific differences, refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments only. Any other changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0070] Embodiment 1 Please refer to Figure 1 , which shows a schematic structural diagram of an optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 sequentially includes, along the optical axis from the object side to the imaging surface S17: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0071] Among them, the first lens L1 has a negative optical power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface; The second lens L2 has a negative optical power, its object side surface S3 is a concave surface, and its image side surface S4 is a concave surface; The third lens L3 has a positive optical power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface; The fourth lens L4 has a positive optical power, its object side surface S7 is a concave surface, and its image side surface S8 is a convex surface; The fifth lens L5 has a positive optical power, its object side S9 is convex, and its image side S10 is convex; The sixth lens L6 has a negative optical power, its object side S11 is concave, and its image side S12 is concave; The seventh lens L7 has a positive optical power, its object side S13 is convex, and its image side S14 is convex; Both the object side S15 and the image side S16 of the filter G1 are flat; The imaging surface S17 is flat.

[0072] The first lens L1 and the fourth lens L4 are made of glass spherical lenses; the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are all made of plastic aspherical lenses.

[0073] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0074] Table 1-1 The surface type parameters of the aspherical lenses of the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0075] Table 1-2 In this embodiment, the astigmatism curve graph, the axial aberration curve graph, and the lateral chromatic aberration curve graph of the optical lens 100 are respectively as Figure 2 , Figure 3 , Figure 4 shown.

[0076] Figure 2 shows the astigmatism curve graph of Embodiment 1, which represents the astigmatism of light rays in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 100 can correct astigmatism well.

[0077] Figure 3 shows the axial aberration curve graph of Embodiment 1 of the present invention, 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. It can be seen from the figure that the offset of the axial aberration is controlled within ±0.01 mm, indicating that the optical lens 100 can correct the axial aberration well.

[0078] Figure 4The vertical chromatic aberration curve diagram of Embodiment 1 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 vertical chromatic aberration value (unit: μm) of each wavelength relative to the central wavelength, and the vertical axis represents the field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm to 3 μm, indicating that the optical lens 100 can excellently correct the chromatic aberration of each field of view.

[0079] Embodiment 2 Please refer to Figure 5 , which shows the structural schematic diagram of the optical lens 200 provided in Embodiment 2 of the present invention. Compared with Embodiment 1, the main difference is that: the object side surface S3 of the second lens L2 is convex near the optical axis; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0080] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0081] Table 2-1 The surface type parameters of the aspherical lens of the optical lens 200 in Embodiment 2 are shown in Table 2-2.

[0082] Table 2-2 In this embodiment, the astigmatism curve diagram, axial aberration curve diagram, and vertical chromatic aberration curve diagram of the optical lens 200 are respectively as Figure 6 , Figure 7 , Figure 8 shown.

[0083] From Figure 6 it can be seen that the astigmatism between the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 200 can well correct astigmatism.

[0084] From Figure 7 it can be seen that the offset of the axial aberration is controlled within ±0.01 mm, indicating that the optical lens 200 can better correct the axial aberration.

[0085] From Figure 8 it can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm to 3 μm, indicating that the optical lens 200 can excellently correct the chromatic aberration of each field of view.

[0086] Embodiment 3 Please refer to Figure 9, which shows a schematic structural diagram of the optical lens 300 provided in Embodiment 3 of the present invention. Compared with Embodiment 1, the main differences are as follows: the object side S13 of the seventh lens L7 is concave near the optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0087] The relevant parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0088] Table 3-1 The surface shape parameters of the aspherical lenses in the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0089] Table 3-2 In this embodiment, the astigmatism curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 300 are respectively as Figure 10 , Figure 11 , Figure 12 shown.

[0090] From Figure 10 , it can be seen that the astigmatism between the meridional image plane and the sagittal image plane is controlled within -0.1 mm to 0, indicating that the optical lens 300 can well correct astigmatism.

[0091] From Figure 11 , it can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can better correct the axial aberration.

[0092] From Figure 12 , it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1 μm to 3 μm, indicating that the optical lens 300 can excellently correct the chromatic aberration of each field of view.

[0093] Embodiment 4 Please refer to Figure 13 , which shows a schematic structural diagram of the optical lens 400 provided in Embodiment 4 of the present invention. Compared with Embodiment 1, the main differences are as follows: the object side S3 of the second lens L2 is convex near the optical axis; the object side S13 of the seventh lens L7 is concave near the optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0094] The relevant parameters of each lens in the optical lens 400 in Embodiment 4 are shown in Table 4-1.

[0095] Table 4-1 The surface shape parameters of the aspherical lens of the optical lens 400 in Embodiment 4 are shown in Table 4-2.

[0096] Table 4-2 In this embodiment, the astigmatism curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 400 are respectively as Figure 14 , Figure 15 , Figure 16 shown.

[0097] From Figure 14 , it can be seen that the astigmatism between the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 400 can correct astigmatism well.

[0098] From Figure 15 , it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 400 can correct the axial aberration better.

[0099] From Figure 16 , it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1 μm to 3 μm, indicating that the optical lens 400 can correct the chromatic aberration of each field of view extremely well.

[0100] Please refer to Table 5 for the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the overall optical length TTL, the aperture value Fno, the true image height IH corresponding to the maximum field of view angle, the incident angle CRA of the chief ray at the maximum image height on the imaging plane, the maximum field of view angle FOV, and the values corresponding to each conditional formula in each embodiment.

[0101] Table 5 In summary of the above embodiments, the optical lens provided by the present invention adopts a seven-piece glass-plastic hybrid structure. Through specific surface shape settings and reasonable optical power distribution, the structure of the optical lens is relatively compact, effectively shortening the overall length of the optical lens, which is beneficial to realizing the miniaturization and light weight of the device; it has a large aperture, enabling the lens to achieve high-definition imaging even in a relatively dark environment; it has a large field of view angle, capable of capturing more pictures. In addition, it can reasonably correct the overall aberration of the optical lens and improve the imaging quality of the optical lens.

[0102] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do 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.

[0103] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: It sequentially includes from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a negative optical power, whose image side is concave; A third lens with a positive optical power, whose object side is convex and whose image side is concave; A fourth lens with a positive optical power, whose object side is concave and whose image side is convex; A fifth lens with a positive optical power, whose object side is convex and whose image side is convex; A sixth lens with a negative optical power, whose object side is concave and whose image side is concave; A seventh lens with a positive optical power, whose image side is convex; The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 50 < f3 / f < 130; The central thickness CT2 of the second lens on the optical axis and the central thickness CT3 of the third lens on the optical axis satisfy: 0.18 < CT2 / CT3 < 0.

36.

2. The optical lens according to claim 1, characterized in that: The curvature radius R5 of the object side of the third lens and the curvature radius R6 of the image side of the third lens satisfy: 0.75 < R5 / R6 < 0.

95.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 3.6 < f4 / f < 4.3; The curvature radius R7 of the object side of the fourth lens and the curvature radius R8 of the image side of the fourth lens satisfy: 1.9 < (R7 + R8) / (R7 - R8) < 2.

1.

4. The optical lens according to claim 1, characterized in that: The sagittal height SAG11 of the clear aperture semi-diameter of the object side of the first lens and the clear aperture semi-diameter DM11 of the object side of the first lens satisfy: 0.16 < SAG11 / DM11 < 0.

2.

5. The optical lens according to claim 1, characterized in that: The sagittal height SAG41 of the clear aperture semi-diameter of the object side of the fourth lens and the clear aperture semi-diameter DM41 of the object side of the fourth lens satisfy: -0.07 < SAG41 / DM41 < -0.05; The sagittal height SAG42 of the clear aperture semi-diameter of the image side of the fourth lens and the clear aperture semi-diameter DM42 of the image side of the fourth lens satisfy: -0.2 < SAG42 / DM42 < -0.

15.

6. The optical lens according to claim 1, characterized in that: The maximum field of view FOV of the optical lens and the f-number Fno of the optical lens satisfy: 105° < FOV / Fno < 130°.

7. The optical lens according to claim 1, characterized in that: The back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5 < BFL / f < 1.

8.

8. The optical lens according to claim 1, characterized in that: The edge thickness ET3 of the third lens and the central thickness CT3 of the third lens on the optical axis satisfy: 0.9 < ET3 / CT3 < 1.

1.

9. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the focal length f2 of the second lens satisfy: 0.6 < f1 / f2 < 0.

7.

10. The optical lens according to claim 1, characterized in that: The overall length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 8.5 < TTL / f < 11.

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