Optical lens

Abstract

The present invention provides an optical lens, which includes, from the object side to the imaging surface along the optical axis: a first lens with negative optical power, whose image side surface is a concave surface; a second lens with positive optical power, whose object side surface is a convex surface; a third lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; a fourth lens with negative optical power, whose object side surface is a concave surface; a fifth lens with negative optical power, whose object side surface is a convex surface at the near optical axis and whose image side surface is a concave surface at the near optical axis; a sixth lens with positive optical power, whose object side surface is a convex surface; and a seventh lens with optical power, whose image side surface is a concave surface at the near optical axis. The optical lens provided by the present invention can improve the imaging quality of the optical lens through specific surface shape matching and reasonable optical power distribution, and has the advantage of excellent imaging quality.

Description

Technical Field

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

[0002] With the rapid development of science and technology, wide-angle lenses are widely used in drones, security, automotive, smart homes and other fields due to their advantages of large field of view and wide shooting format. However, due to differences in application environments, the performance requirements for the optical lenses are getting higher and higher. For example, in some application scenarios with complex environments, the lens is required to be able to produce clear images under high and low temperature conditions with large temperature differences; at the same time, it is required to work effectively during the day and at night to meet shooting needs; today's wide-angle lenses are constantly developing towards low cost, small size, and high-definition image quality, so the corresponding new low-cost, athermal wide-angle lenses with new architectures have become the objects to be explored.

[0003] Traditional all-glass lenses have many lenses, high cost, low pixels, insufficient resolution, large size, and lack of clear imaging capabilities in low-light environments. Therefore, it is necessary to develop an optical lens with good imaging effects to better meet market demand. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide an optical lens having the advantage of excellent imaging quality.

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

[0006] A first lens having negative optical power, whose image side surface is concave;

[0007] a second lens having positive refractive power and a convex object-side surface;

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

[0009] a fourth lens element having negative optical power and a concave object side surface;

[0010] A fifth lens having negative optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis;

[0011] a sixth lens having positive refractive power and a convex object-side surface;

[0012] A seventh lens element having optical power, wherein the image side surface thereof is concave at a position close to the optical axis;

[0013] Among them, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.1 < TTL / f < 4.3; the true image height IH corresponding to the maximum field of view angle of the optical lens, the maximum field of view angle FOV of the optical lens and the effective focal length f of the optical lens satisfy: 35° < (f × FOV) / IH < 45°.

[0014] Further preferably, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 3.2 < IH / f < 4; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.85 < TTL / IH < 1.35.

[0015] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.7 < f1 / f < -1.1; the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1.5 < f1 / f2 < -0.5.

[0016] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1 < f2 / f < 2.5; the refractive index Nd2 of the second lens satisfies: 1.75 < Nd2 < 1.9.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.8 < f3 / f < 8; the curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy: 0.1 < (R5 + R6) / (R5 - R6) < 0.7.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -26 < f4 / f < -1; the effective focal length f of the optical lens and the curvature radius R7 of the object side surface of the fourth lens satisfy: -50 < R7 / f < -1.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -25 < f5 / f < -0.5; the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.4 < f6 / f < 2.5.

[0020] Further preferably, the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: 0.8 < R9 / f < 5; the effective focal length f of the optical lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.25 < R10 / f < 1.

[0021] Further preferably, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.65 <f3 / f4<-0.2。

[0022] Further preferably, the seventh lens has positive focal power, and the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: <f7 / f<20。

[0023] Further preferably, the seventh lens has a negative optical power, and the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -1.8 <f7 / f<-1.2。

[0024] Compared with the prior art, the optical lens provided by the present invention adopts seven lenses with specific optical focal lengths. Through specific surface shape matching and reasonable optical focal length distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as wide angle, miniaturization, large target area, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0026] Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0027] Figure 2 It is a field curvature curve diagram of the optical lens in Example 1 of the present invention.

[0028] Figure 3 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0029] Figure 4 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0030] Figure 5 4 is a field curvature curve diagram of the optical lens in Example 2 of the present invention.

[0031] Figure 6 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0032] Figure 7 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0033] Figure 8 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0034] Fig. 9 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0035] Fig.10 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0036] Fig.11 It is a field curvature curve diagram of the optical lens in Example 4 of the present invention.

[0037] Fig.12 Graph showing the vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0038] Fig.13 Schematic diagram of the structure of the optical lens in Example 5 of the present invention.

[0039] Fig.14 4 is a field curvature curve diagram of the optical lens in Example 5 of the present invention.

[0040] Fig.15 Graph showing the vertical axis chromatic aberration of the optical lens in Example 5 of the present invention.

[0041] Fig.16 Schematic diagram of the structure of the optical lens in Example 6 of the present invention.

[0042] Fig.17 4 is a field curvature curve diagram of the optical lens in Example 6 of the present invention.

[0043] Fig.18 Graph showing the vertical axis chromatic aberration of the optical lens in Example 6 of the present invention.

[0044] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0045] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application, and are not intended to 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.

[0046] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0047] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0048] 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 is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0049] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", 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 expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0050] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0051] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0052] The optical lens provided by the embodiment of the present invention comprises seven lenses in total, and the optical lens comprises, in order from the object side to the imaging surface along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0053] In some embodiments, the first lens may have a negative focal power. Its object side may be concave or convex, and its image side is concave. The second lens may have a positive focal power. Its object side is convex, and its image side may be concave or convex. The third lens may have a positive focal power. Its object side is convex, and its image side is convex. The fourth lens may have a negative focal power. Its object side is concave, and its image side may be concave or convex. The fifth lens may have a negative focal power. Its object side is convex near the optical axis, and its image side is concave near the optical axis. The sixth lens may have a positive focal power. Its object side is convex, and its image side may be concave or convex. The seventh lens may have a positive or negative focal power. Its object side may be concave or convex, and its image side is concave near the optical axis.

[0054] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the second lens and the third 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 second lens and the third lens, it is convenient for correcting the diaphragm aberration.

[0055] In some embodiments, the optical lens may further include a filter, and 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.

[0056] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.1 < TTL / f < 4.3. Meeting the above conditions can effectively limit the length of the lens, which is beneficial to the miniaturization of the optical lens.

[0057] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens, the maximum field of view angle FOV of the optical lens, and the effective focal length f of the optical lens satisfy: 35° < (f × FOV) / IH < 45°. Meeting the above conditions is beneficial to achieving the balance between the large field of view angle and large target surface imaging of the optical lens by reasonably restricting the relationship between the focal length, field of view angle, and image height of the optical lens.

[0058] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 3.2 < IH / f < 4. Meeting the above conditions can not only achieve the wide-angle characteristic to meet the large-range shooting requirements, but also achieve the large image surface characteristic to improve the imaging quality of the optical lens.

[0059] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.85 < TTL / IH < 1.35. Meeting the above conditions can better achieve the miniaturization of the lens. At the same time, when ensuring the same total length of the lens, it has a larger image plane, can match a larger-sized imaging chip to achieve high-definition imaging.

[0060] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.7 < f1 / f < -1.1. Meeting the above conditions can make the first lens have a large negative refractive power, which is beneficial to increasing the field of view angle, and can collect as much marginal field light as possible into the rear system to achieve large-angle light collection.

[0061] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1.5 < f1 / f2 < -0.5. Meeting the above conditions can effectively converge a wide range of light entering the system, and at the same time is beneficial to the rear optical system to correct large-angle aberrations, thereby achieving the balance of the miniaturization and high pixel count of the optical lens.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1 < f2 / f < 2.5. Meeting the above conditions can effectively converge a wide range of light entering the system, which is beneficial to avoiding excessive light deflection caused by overly concentrated optical power of the first lens and reducing the difficulty of aberration correction.

[0063] In some embodiments, the refractive index Nd2 of the second lens satisfies: 1.75 < Nd2 < 1.9. Meeting the above conditions, the second lens before the aperture uses a glass lens with a high refractive index, which is beneficial to the back focal compensation of the optical system at high and low temperatures, improves the imaging quality of the system at high and low temperatures, and achieves good thermal stability.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.8 < f3 / f < 8. Meeting the above conditions, by reasonably setting the focal length of the third lens, it is beneficial to the smooth transition of light, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0065] In some embodiments, the curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy: 0.1 < (R5 + R6) / (R5 - R6) < 0.7. Meeting the above conditions, by reasonably setting the surface shape of the third lens, it is beneficial to better achieve the convergence of light, shorten the distance of light reaching the next lens, and is beneficial to reducing the total length of the optical lens.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -26 < f4 / f < -1; the effective focal length f of the optical lens and the curvature radius R7 of the object side surface of the fourth lens satisfy: -50 < R7 / f < -1. Meeting the above conditions is beneficial to diverging the light converged by the second lens and the third lens, balancing the aberration of the optical lens, and improving the imaging quality of the optical lens.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -25 < f5 / f < -0.5. Meeting the above conditions can further diverge the incident light, can achieve the divergence of the light in the central field of view, and at the same time combine the curved surface shape in the edge region of the fifth lens to reduce the exit angle of the light in the edge field of view and improve the relative illumination of the edge field of view.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.4 < f6 / f < 2.5. Meeting the above conditions is beneficial to converging the diverging light to the rear optical system, can shorten the optical path of the peripheral light reaching the imaging surface, can effectively shorten the total length, and at the same time improve the resolution quality.

[0069] In some embodiments, the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: 0.8 < R9 / f < 5; the effective focal length f of the optical lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.25 < R10 / f < 1. Meeting the above conditions, setting the object side surface of the fifth lens to be convex and the image side surface to be concave can diverge the light converged by the front-end lens, enabling it to reach a higher imaging position, appropriately separating the optical paths of the light in each field of view, and gently diverging it to the rear lens system.

[0070] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.65 < f3 / f4 < -0.2. Meeting the above conditions is beneficial to the smooth transition of light, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens.

[0071] In some embodiments, the seventh lens may have a positive optical power, and the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 5 < f7 / f < 20. Meeting the above conditions, setting the seventh lens to have a positive optical power is beneficial to the gentle convergence of light, can shorten the distance to the next lens, and is beneficial to reducing the total length of the optical lens.

[0072] In some embodiments, the seventh lens may also have a negative optical power, and the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -1.8 < f7 / f < -1.2. Meeting the above conditions and setting the seventh lens to have a negative optical power is conducive to diverging the incident light, causing the peripheral light and the central light to turn upwards, reaching a higher imaging position, and better realizing large image plane imaging of the lens.

[0073] In some embodiments, the overall optical length TTL of the optical lens and the back focal length BFL of the optical lens satisfy: 0.05 < BFL / TTL < 0.15. Meeting the above conditions can make the lens have an appropriate back focus, ensure the compatibility between the lens and the body, and at the same time make the structure of the lens more compact.

[0074] In some embodiments, the radius of curvature R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.45 < R2 / f < 0.85. Meeting the above conditions can effectively control the surface shape of the image side surface of the first lens, is conducive to increasing the field of view angle, and at the same time controls the front aperture of the optical lens, realizing the balance between a large field of view and miniaturization.

[0075] In some embodiments, the true 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: 8 < IH / EPD < 10. Meeting the above conditions can better balance the large image plane imaging and small aperture size of the lens.

[0076] In some embodiments, the effective focal length f of the optical lens and the combined focal length f45 of the fourth lens and the fifth lens satisfy: -4 < f45 / f < -0.4. Meeting the above conditions, the incident light can be diverged to a certain extent by the middle fourth and fifth lenses, causing the peripheral light and the central light to turn upwards, reaching a higher imaging position, thereby realizing large image plane imaging of the lens.

[0077] In some embodiments, the optical lens satisfies the conditional formula: 2mm < f < 2.6mm, 7.5mm < TTL < 10mm, 2 < Fno < 2.6, 7.5mm < IH < 8.5mm, 140° < FOV < 160°, where f represents the effective focal length of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, and FOV represents the maximum field of view angle of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of a large wide angle, a large image plane, and miniaturization.

[0078] In some embodiments, the seven lenses in the optical lens can all be plastic lenses or glass-plastic hybrid materials. Preferably, the optical lens of the present invention uses a seven-piece glass-plastic hybrid lens structure, which can make the optical lens better match the large target chip to achieve high-definition imaging, and can also achieve the miniaturization of the optical lens, a reasonable balance of large image surface and wide angle. Specifically, the second lens can be a glass lens, and the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are all plastic lenses; the glass-plastic hybrid structure can effectively reduce costs, correct aberrations, reduce volume, and provide a more cost-effective optical lens product.

[0079] 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 may be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of lenses, and better realizing miniaturization of lenses. More specifically, in the optical lens provided by the present invention, the second lens may be a spherical lens, and the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens may be aspherical lenses.

[0080] 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 equations:

[0081] ;

[0082] Among them, z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, K is the quadratic surface coefficient, B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0083] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please 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. Any other changes, substitutions, combinations or simplifications that do not deviate 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.

[0084] Example 1

[0085] See also Figure 1, shown is a schematic diagram of the structure of the optical lens 100 provided in Example 1 of the present invention, and the optical lens 100 includes, along the optical axis from the object side to the imaging surface S17, a first lens L1, a second lens L2, an aperture ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and a filter G1.

[0086] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0087] The second lens L2 has positive refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave;

[0088] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is convex;

[0089] The fourth lens L4 has negative refractive power, its object-side surface S7 is concave, and its image-side surface S8 is concave;

[0090] The fifth lens L5 has negative refractive power, an object-side surface S9 thereof is convex at the near optical axis, and an image-side surface S10 thereof is concave at the near optical axis;

[0091] The sixth lens L6 has positive refractive power, an object-side surface S11 thereof is convex, and an image-side surface S12 thereof is convex;

[0092] The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis;

[0093] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0094] The imaging surface S17 is a plane.

[0095] The second lens L2 is a glass spherical lens; the first lens L1, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all plastic aspherical lenses.

[0096] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0097] Table 1-1

[0098]

[0099] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0100] Table 1-2

[0101]

[0102] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 shown.

[0103] Figure 2 The field curvature curve of Example 1 is shown, which represents the field curvature of light on 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 field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.15mm, indicating that the optical lens 100 can well correct the field curvature.

[0104] Figure 3 The vertical chromatic aberration curve of Example 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 of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized 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 ±3 μm, indicating that the optical lens 100 can correct the vertical chromatic aberration well.

[0105] Example 2

[0106] See also Figure 4 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main differences of this embodiment are: the image side surface S8 of the fourth lens L4 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0107] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0108] Table 2-1

[0109]

[0110] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0111] Table 2-2

[0112]

[0113] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 5 , Figure 6 shown.

[0114] from Figure 5 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 200 can correct the field curvature well.

[0115] from Figure 6 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4μm, indicating that the optical lens 200 can correct the vertical axis chromatic aberration well.

[0116] Example 3

[0117] See also Figure 7 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object side surface S1 of the first lens L1 is concave at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0118] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0119] Table 3-1

[0120]

[0121] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0122] Table 3-2

[0123]

[0124] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 300 are respectively as follows: Figure 8 , Fig. 9 shown.

[0125] from Figure 8 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 300 can correct the field curvature well.

[0126] from Fig. 9 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 300 can correct the vertical axis chromatic aberration well.

[0127] Example 4

[0128] See also Fig.10 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 5 of the present invention. Compared with Example 1, the main differences of this embodiment are: the seventh lens L7 has positive focal power; the image side surface S4 of the second lens L2 is a convex surface; the image side surface S12 of the sixth lens L6 is a concave surface at the near optical axis; the object side surface S13 of the seventh lens L7 is a convex surface at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0129] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0130] Table 4-1

[0131]

[0132] The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0133] Table 4-2

[0134]

[0135] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 400 are respectively as follows: Fig.11 , Fig.12 shown.

[0136] from Fig.11 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 400 can correct the field curvature well.

[0137] from Fig.12 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3μm, indicating that the optical lens 400 can correct the vertical axis chromatic aberration well.

[0138] Example 5

[0139] See also Fig.13 , shown is a schematic diagram of the structure of the optical lens 500 provided in Example 5 of the present invention. Compared with Example 1, the main differences of this embodiment are: the seventh lens L7 has positive focal power; the image side surface S8 of the fourth lens L4 is convex at the near optical axis; the image side surface S12 of the sixth lens L6 is concave at the near optical axis; the object side surface S13 of the seventh lens L7 is convex at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0140] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0141] Table 5-1

[0142]

[0143] The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0144] Table 5-2

[0145]

[0146] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 500 are respectively as follows: Fig.14 , Fig.15 shown.

[0147] from Fig.14 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.2mm, indicating that the optical lens 500 can correct the field curvature well.

[0148] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3μm, indicating that the optical lens 500 can correct the vertical axis chromatic aberration well.

[0149] Example 6

[0150] See also Fig.16 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 6 of the present invention. Compared with Example 1, the main differences of this embodiment are: the seventh lens L7 has positive focal power; the image side surface S4 of the second lens L2 is convex at the near optical axis; the image side surface S8 of the fourth lens L4 is convex at the near optical axis; the image side surface S12 of the sixth lens L6 is concave at the near optical axis; the object side surface S13 of the seventh lens L7 is convex at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0151] The relevant parameters of each lens in the optical lens 600 in Example 6 are shown in Table 6-1.

[0152] Table 6-1

[0153]

[0154] The surface parameters of the aspheric lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0155] Table 6-2

[0156]

[0157] In this embodiment, the field curvature curve and the vertical axis chromatic aberration curve of the optical lens 600 are respectively as follows: Fig.17 , Fig.18 shown.

[0158] from Fig.17 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.1mm, indicating that the optical lens 600 can correct the field curvature well.

[0159] from Fig.18It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4μm, indicating that the optical lens 600 can correct the vertical axis chromatic aberration well.

[0160] Please refer to Table 7, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the chief ray incident angle CRA at the maximum image height, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0161] Table 7

[0162]

[0163] Compared with the prior art, the optical lens provided by the present invention has at least the following advantages:

[0164] (1) The optical lens provided by the present invention adopts a seven-piece glass-plastic hybrid structure. Through a specific surface shape setting and a reasonable optical focal length distribution, the structure of the optical lens is relatively compact, and a large field of view of the lens can be achieved, thereby being able to obtain more scene information and meet the needs of large-scale detection of the optical lens.

[0165] (2) The optical lens provided by the present invention also has the feature of a large target surface, and can carry a larger chip to achieve high-definition imaging; at the same time, it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has a high pixel while effectively shortening the overall length of the optical lens.

[0166] (3) The optical lens provided by the present invention adopts a glass-plastic hybrid structure, which not only makes the lens have good thermal stability, but also greatly reduces the production cost of the lens, reduces the size of the lens, and better realizes the miniaturization of the lens.

[0167] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0168] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which 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 attached claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: It sequentially includes from the object side to the imaging plane along the optical axis: A first lens with a negative optical power, whose image side is concave; A second lens with a positive optical power, whose object side is convex; A third lens with a positive optical power, whose object side is convex and whose image side is convex; A fourth lens with a negative optical power, whose object side is concave; A fifth lens with a negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A sixth lens with a positive optical power, whose object side is convex; A seventh lens with an optical power, whose image side is concave near the optical axis; Wherein, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 3.1 < TTL / f < 4.3; the true image height IH corresponding to the maximum field of view angle of the optical lens, the maximum field of view angle FOV of the optical lens and the effective focal length f of the optical lens satisfy: 35° < (f × FOV) / IH < 45°; the true 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: 8 < IH / EPD < 10.

2. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 3.2 < IH / f < 4; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.85 < TTL / IH < 1.

35.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.7 < f1 / f < -1.1; the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1.5 < f1 / f2 < -0.

5.

4. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1 < f2 / f < 2.5; the refractive index Nd2 of the second lens satisfies: 1.75 < Nd2 < 1.

9.

5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.8 < f3 / f < 8; 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: 0.1 < (R5 + R6) / (R5 - R6) < 0.

7.

6. 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: -26 < f4 / f < -1; the effective focal length f of the optical lens and the curvature radius R7 of the object side of the fourth lens satisfy: -50 < R7 / f < -1.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -25 < f5 / f < -0.5; the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.4 < f6 / f < 2.

5.

8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the curvature radius R9 of the object side of the fifth lens satisfy: 0.8 < R9 / f < 5; the effective focal length f of the optical lens and the curvature radius R10 of the image side of the fifth lens satisfy: 0.25 < R10 / f < 1.

9. The optical lens according to claim 1, characterized in that: The focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.65 <f3 / f4<-0.2。 10. The optical lens according to claim 1, characterized in that: The seventh lens has positive refractive power.

11. The optical lens according to claim 1, characterized in that: The seventh lens has a negative optical power, and the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -1.8 <f7 / f<-1.2。

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