Optical lens

Abstract

The present invention provides an optical lens, which 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 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 image side is convex; a fourth lens with a negative optical power, whose image side is concave; a fifth lens with a positive optical power, whose image side is convex; a sixth lens with a negative optical power, whose image side is concave near the optical axis; a seventh lens with an optical power, whose object side is convex near the optical axis and image side is concave near the optical axis; the total optical length TTL of the optical lens and the effective focal length f satisfy: 3.15 < TTL / f < 4; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view satisfy: 0.95 < TTL / IH < 1.2. The optical lens provided by the present invention has one or more advantages such as large wide-angle, miniaturization, large image surface, and high imaging quality.

Description

Technical Field

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

[0002] With the rapid development of fields such as drones, security, and automobiles, the pursuit of the imaging effect of the lenses carried by them has become more diversified. Currently, drones are developing rapidly and have won the favor of consumers with their unique high-altitude perspective and wide shooting range. Correspondingly, the demand for the optical lenses supporting them is also increasing. The optical lenses carried by them require both high-definition image quality and the ability to present large local details, so as to achieve that the local details can be vividly shown even in the high-altitude view and capture local close-up pictures.

[0003] Therefore, it is necessary to develop an optical lens with good imaging effect to better meet the market demand. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to provide an optical lens with excellent imaging quality.

[0005] The present invention provides an optical lens, which has a total of seven lenses, and sequentially includes from the object side to the imaging surface along the optical axis:

[0006] A first lens with negative optical power, whose object side is convex and whose image side is concave;

[0007] A second lens with positive optical power, whose object side is convex;

[0008] A third lens with positive optical power, whose object side is convex and whose image side is convex;

[0009] A fourth lens with negative optical power, whose image side is concave;

[0010] A fifth lens with positive optical power, whose image side is convex;

[0011] A sixth lens with negative optical power, whose image side is concave near the optical axis;

[0012] A seventh lens with optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis;

[0013] Wherein, the total optical length TTL of the optical lens and the effective focal length f satisfy: 3.15 < TTL / 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 satisfy: 0.95 < TTL / IH < 1.2.

[0014] Further preferably, 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°.

[0015] Further preferably, the effective focal length f of the optical lens and the combined focal length fb of the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: 1.1 < fb / f < 1.8.

[0016] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.5 < f1 / f < -1; the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1 < f1 / f2 < -0.5.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.5 < f2 / f < 2.5; the effective focal length f of the optical lens and the curvature radius R3 of the object side surface of the second lens satisfy: 1.2 < R3 / f < 2.2.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.1 < f3 / f < 1.7; 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: -7 < R5 / R6 < -1.2.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -8 < f4 / f < -3.

[0020] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1 < f5 / f < 5; the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -3 < f6 / f < -1.

[0021] Further preferably, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 1 < f2 / f3 < 1.6; the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 1.1 < CT2 / CT3 < 1.8.

[0022] Further preferably, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 < f3 / f4 < -0.1.

[0023] 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 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 image surface, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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:

[0025] Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0026] Figure 2 Graph showing the astigmatism of the optical lens in Example 1 of the present invention.

[0027] Figure 3 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0028] Figure 4 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0029] Figure 5 Graph showing the astigmatism of the optical lens in Embodiment 2 of the present invention.

[0030] Figure 6 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0031] Figure 7 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0032] Figure 8 4 is an astigmatism curve diagram of the optical lens in Example 3 of the present invention.

[0033] Fig. 9 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0034] Fig.10 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0035] Fig.11 4 is an astigmatism curve diagram of the optical lens in Example 4 of the present invention.

[0036] Fig.12 Graph showing the vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0037] Fig.13 Schematic diagram of the structure of the optical lens in Example 5 of the present invention.

[0038] Fig.14 4 is an astigmatism curve diagram of the optical lens in Example 5 of the present invention.

[0039] Fig.15 Graph showing the vertical axis chromatic aberration of the optical lens in Example 5 of the present invention.

[0040] Fig.16 Schematic diagram of the structure of the optical lens in Example 6 of the present invention.

[0041] Fig.17 4 is an astigmatism curve diagram of the optical lens in Example 6 of the present invention.

[0042] Fig.18 Graph showing the vertical axis chromatic aberration of the optical lens in Example 6 of the present invention.

[0043] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] In some embodiments, the first lens may have a negative optical power, and its object side surface is convex, and its image side surface is concave. The second lens may have a positive optical power, and its object side surface is convex, and its image side surface may be a plane, a convex surface, or a concave surface. The third lens may have a positive optical power, and its object side surface is convex, and its image side surface is convex. The fourth lens may have a negative optical power, and its object side surface may be concave or convex, and its image side surface is concave. The fifth lens may have a positive optical power, and its object side surface may be concave or convex at the near optical axis, and its image side surface is convex. The sixth lens may have a negative optical power, and its object side surface may be concave or convex at the near optical axis, and its image side surface is concave at the near optical axis. The seventh lens may have a positive optical power or a negative optical power, and its object side surface is convex at the near optical axis, and its image side surface is concave at the near optical axis.

[0053] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the second lens and the third lens. It is understood that the aperture is used to limit the amount of light entering to change the brightness of the image. When the aperture is located between the second lens and the third lens, it is convenient to correct the aperture aberration.

[0054] In some embodiments, the optical lens may further include a filter disposed between the seventh lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0055] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f satisfy: 3.15 < TTL / f < 4. Satisfying the above conditional formula can effectively limit the length of the lens and is conducive to realizing the miniaturization of the optical lens.

[0056] 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 satisfy: 0.95 < TTL / IH < 1.2. Satisfying the above conditional formula ensures that, with the same total length of the lens, it has a larger image surface, can match a larger-sized imaging chip to achieve high-definition imaging, and better realizes the balance between the small total length and the large image surface of the 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°. Satisfying the above conditional formula is conducive to realizing the balance between the large field of view angle and the 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 combined focal length fb of the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: 1.1 < fb / f < 1.8. Satisfying the above conditional formula is conducive to balancing the spherical aberration and coma generated by the front lens of the diaphragm by reasonably setting the optical power of the rear-end lens and improving the imaging quality of the optical lens.

[0059] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.5 < f1 / f < -1. Satisfying the above conditional formula can make the first lens have a large negative refractive power, which is conducive to realizing the large field of view angle of the lens, while reducing the influence of the distortion generated by the first lens itself on the overall distortion of the optical lens and reducing the difficulty of correcting the distortion of the rear-end lens.

[0060] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1 < f1 / f2 < -0.5. Satisfying the above conditional formula, on the premise of ensuring that the optical lens has an ultra-wide angle, it avoids the excessive light deflection caused by the over-concentration of the optical power of the first lens and reduces the difficulty of correcting the chromatic aberration of the optical lens.

[0061] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.5 < f2 / f < 2.5; the effective focal length f of the optical lens and the curvature radius R3 of the object side surface of the second lens satisfy: 1.2 < R3 / f < 2.2. Satisfying the above conditional expressions can effectively converge a wide range of light rays 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.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.1 < f3 / f < 1.7; 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: -7 < R5 / R6 < -1.2. Satisfying the above conditional expressions is beneficial to the smooth transition of light rays by reasonably setting the focal length and surface shape of the third lens, facilitating the correction of astigmatism and field curvature, and improving the imaging quality of the optical lens.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -8 < f4 / f < -3. Satisfying the above conditional expressions is beneficial to reducing the deflection degree of incident light rays, avoiding excessive aberration caused by overly strong refractive changes, and at the same time is beneficial to balancing various aberrations generated by the front lens group, thereby improving the overall imaging quality.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1 < f5 / f < 5. Satisfying the above conditional expressions can control the spherical aberration contribution of the fifth lens within a reasonable range, enabling the lens to have a high axial imaging resolution and being beneficial to achieving high-definition imaging of the lens.

[0065] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -3 < f6 / f < -1. Satisfying the above conditional expressions is beneficial to increasing the divergence degree of light rays, increasing the area of light rays entering the imaging surface, achieving large target surface imaging of the lens, and improving the imaging quality of the optical lens.

[0066] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 1 < f2 / f3 < 1.6; the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 1.1 < CT2 / CT3 < 1.8. Satisfying the above conditional expressions is beneficial to the smooth transition of light rays by reasonably setting the focal length and thickness relationship of the second and third lenses, and at the same time correcting various aberrations of the optical lens, thereby improving the imaging quality of the optical lens.

[0067] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 < f3 / f4 < -0.1. Meeting the above conditional formula is conducive to enabling the diverging light to smoothly enter the rear optical system, reducing the difficulty of correcting field curvature and distortion, and improving the overall resolution.

[0068] 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 satisfy: 3.2 < IH / f < 3.8. Meeting the above conditional formula can not only achieve the wide-angle characteristic to meet the large-range shooting requirements, but also achieve the large image plane characteristic to improve the imaging quality of the optical lens.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.5 < |f7 / f| < 3.5. Meeting the above conditional formula can effectively improve the light converging ability of the optical lens, shorten the total length of the optical lens, and at the same time make the distortion optimization effect obvious and improve the imaging quality of the optical lens.

[0070] In some embodiments, the object-side curvature radius R1 of the first lens and the image-side curvature radius R2 of the first lens satisfy: 1.1 < (R1 + R2) / (R1 - R2) < 1.65. Meeting the above conditional formula is conducive to achieving the ultra-wide-angle characteristic, so as to obtain more scene information and meet the requirements of large-range detection of the optical lens.

[0071] In some embodiments, the distance CT12 between the first lens and the second lens on the optical axis and the central thickness CT2 of the second lens satisfy: 1 < CT12 / CT2 < 1.6. Meeting the above conditional formula can reduce the system performance sensitivity, ensure the lens processability and assembly stability at the same time, and improve the assembly yield.

[0072] In some embodiments, the object-side clear aperture DM11 of the first lens and the image-side clear aperture DM72 of the seventh lens satisfy: 0.8 < DM11 / DM72 < 1.1. Meeting the above conditional formula can make the lens have a larger entrance aperture. While ensuring that as much light as possible enters the system, it increases the area of light entering the imaging plane, which is conducive to achieving the balance of the large image plane and large aperture of the lens.

[0073] In some embodiments, the optical lens satisfies the conditional formula: 2mm < f < 3mm, 130° < FOV < 150°, 7.5mm < TTL < 10mm, 7.5mm < IH < 9mm, where f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, TTL represents the total optical length of the optical lens, and IH represents the true image height corresponding to 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 field of view angle, a large image plane, and miniaturization.

[0074] In some embodiments, all seven lenses in the optical lens can be made of plastic lenses or adopt a combination structure of glass and plastic materials. Preferably, the optical lens of the present invention adopts a combination structure of seven lenses with glass and plastic, which can enable the optical lens to better match a large target surface chip to achieve high-definition imaging, and at the same time can also achieve a reasonable balance of miniaturization, large image plane, and large wide angle of the optical lens. Specifically, the second lens can be made of 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; adopting a glass-plastic hybrid structure can effectively reduce costs, correct aberrations, reduce volume, and provide an optical lens product with higher cost performance.

[0075] In some embodiment modes, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt 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 second lens can adopt a spherical lens, and the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt aspherical lenses.

[0076] In each embodiment of the present invention, when the lens adopts an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0077] ;

[0078] 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.

[0079] 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.

[0080] Example 1

[0081] 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.

[0082] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0083] The second lens L2 has positive refractive power, its object side surface S3 is convex, and its image side surface S4 is flat;

[0084] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is convex;

[0085] The fourth lens L4 has negative refractive power, its object-side surface S7 is concave, and its image-side surface S8 is concave;

[0086] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex at the near optical axis, and its image-side surface S10 is convex;

[0087] The sixth lens L6 has negative refractive power, an object-side surface S11 thereof is convex at the near optical axis, and an image-side surface S12 thereof is concave at the near optical axis;

[0088] The seventh lens L7 has positive refractive power, its object-side surface S13 is convex, and its image-side surface S14 is concave;

[0089] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0090] The imaging surface S17 is a plane.

[0091] 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.

[0092] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0093] Table 1-1

[0094]

[0095] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0096] Table 1-2

[0097]

[0098] In this embodiment, the astigmatism curve and the vertical axis chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 shown.

[0099] Figure 2 The astigmatism curve of Example 1 is shown, which represents the astigmatism of light in the meridional image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the 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 ±0.15mm, indicating that the optical lens 100 can correct the astigmatism well.

[0100] Figure 3 The vertical axis 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 axis 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 axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, indicating that the optical lens 100 can correct chromatic aberration well.

[0101] Example 2

[0102] 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 difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0103] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0104] Table 2-1

[0105]

[0106] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0107] Table 2-2

[0108]

[0109] In this embodiment, the astigmatism curve and the vertical axis chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 5 , Figure 6 As shown. Figure 5 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 200 can correct the astigmatism well. Figure 6 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0110] Example 3

[0111] 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 difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0112] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0113] Table 3-1

[0114]

[0115] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0116] Table 3-2

[0117]

[0118] In this embodiment, the astigmatism curve and the vertical axis chromatic aberration curve of the optical lens 300 are respectively as follows: Figure 8 , Fig. 9 As shown. Figure 8 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 300 can correct the astigmatism well. Fig. 9 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0119] Example 4

[0120] See also Fig.10, shown is a schematic diagram of the structure of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, this embodiment has the following main differences: the seventh lens L7 has negative optical power; the object side surface S9 of the fifth lens L5 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.

[0121] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0122] Table 4-1

[0123]

[0124] The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0125] Table 4-2

[0126]

[0127] In this embodiment, the astigmatism curve, f-tan(θ) distortion curve, and vertical axis chromatic aberration curve of the optical lens 400 are respectively as follows: Fig.11 , Fig.12 As shown. Fig.11 It can be seen from the figure that the astigmatism 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 astigmatism well. Fig.12 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5μm, indicating that the optical lens 400 can correct chromatic aberration well.

[0128] Example 5

[0129] See also Fig.13 , shown is a schematic diagram of the structure of an optical lens 500 provided in Example 5 of the present invention. Compared with Example 1, this embodiment has the following main differences: the seventh lens L7 has negative optical power; the object side surface S7 of the fourth lens L4 is convex at the near optical axis, and the object side surface S11 of the sixth lens L6 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0130] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0131] Table 5-1

[0132]

[0133] The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0134] Table 5-2

[0135]

[0136] In this embodiment, the astigmatism curve and the vertical axis chromatic aberration curve of the optical lens 500 are respectively as follows: Fig.14 , Fig.15 As shown. Fig.14 It can be seen from the figure that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 500 can correct the astigmatism well. 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 chromatic aberration well.

[0137] Example 6

[0138] See also Fig.16 , which is a schematic diagram of the structure of an optical lens 600 provided in Example 6 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the seventh lens L7 has negative optical power; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0139] The relevant parameters of each lens in the optical lens 600 in Example 6 are shown in Table 6-1.

[0140] Table 6-1

[0141]

[0142] The surface parameters of the aspheric lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0143] Table 6-2

[0144]

[0145] In this embodiment, the astigmatism curve and the vertical axis chromatic aberration curve of the optical lens 600 are respectively as follows: Fig.17 , Fig.18 As shown. Fig.17 It can be seen from the figure that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 600 can correct the astigmatism well. Fig.18 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 600 can correct chromatic aberration well.

[0146] 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.

[0147] Table 7

[0148]

[0149] Compared with the prior art, the optical lens provided by the present invention has at least the following advantages:

[0150] 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 angle of the lens can be achieved. At the same time, it has a large image surface and can 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, better meeting the use requirements of miniaturization, large image surface, and wide-angle shooting of drones.

[0151] 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.

[0152] 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: From the object side to the imaging plane along the optical axis, it successively includes: A first lens with negative optical power, whose object side is convex and whose image side is concave; A second lens with positive optical power, whose object side is convex; A third lens with positive optical power, whose object side is convex and whose image side is convex; A fourth lens with negative optical power, whose image side is concave; A fifth lens with positive optical power, whose image side is convex; A sixth lens with negative optical power, whose image side is concave near the optical axis; A seventh lens with optical power, whose object side is convex near the optical axis and 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 satisfy: 3.258 ≤ TTL / 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 satisfy: 0.980 ≤ TTL / IH < 1.2; the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -3 < f6 / f ≤ -1.

536.

2. The optical lens according to claim 1, characterized in that: 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°.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the combined focal length fb of the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: 1.1 < fb / f < 1.

8.

4. 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: -1.5 < f1 / f < -1; the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -1 < f1 / f2 < -0.

5.

5. 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: 1.5 < f2 / f < 2.5; the effective focal length f of the optical lens and the curvature radius R3 of the object side of the second lens satisfy: 1.2 < R3 / f < 2.

2.

6. 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: 1.1 < f3 / f < 1.7; 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: -7 < R5 / R6 < -1.

2.

7. 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: -8 < f4 / f < -3.

8. 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: 1 < f5 / f < 5.

9. The optical lens according to claim 1, characterized in that: The focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 1 < f2 / f3 < 1.6; the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 1.1 < CT2 / CT3 < 1.

8.

10. 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: -0.5 < f3 / f4 < -0.1.

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