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 convex surface; the fourth lens has positive focal power, and the object side surface of the fourth lens is a convex surface near the optical axis; the fifth lens has positive focal power, the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface near the optical axis; the sixth lens has positive focal power, the object side surface of the sixth lens near the optical axis is a convex surface, and the image side surface of the sixth lens is a convex surface; and the object side surface of the seventh lens is a concave surface. According to the optical lens provided by the invention, through specific surface shape setting and reasonable focal power distribution, the overall aberration of the optical lens can be reasonably corrected, so that the optical lens has one or more advantages of large aperture, miniaturization, 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] With the rapid development of electronic devices (such as laptops, tablets, mobile phones, etc.), electronic devices available for imaging have rapidly become popular in modern video conferencing. With the miniaturization development of various electronic devices, the demand for miniaturization of optical lenses provided in electronic devices is becoming increasingly intense. However, traditional optical lenses used in video conferencing often have a relatively large volume and can no longer meet the requirements of miniaturization of electronic devices. Moreover, the imaging picture quality of traditional optical lenses is poor, especially the quality of images and videos taken in a dim environment is poor, which cannot meet the requirements of high-definition imaging for video conferencing. How to make the imaging lens for video conferencing take into account miniaturization and high picture quality has become a difficult problem to be solved urgently at present. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens, which has one or more advantages such as a large aperture, miniaturization, and high imaging quality.

[0004] The technical solution adopted by the present invention is as follows: An optical lens, comprising a total of seven lenses, which sequentially include from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, the object side surface thereof is convex, and the image side surface thereof is concave; A second lens with a negative optical power, the image side surface thereof is concave; A third lens with a positive optical power, the object side surface thereof is convex, and the image side surface thereof is convex; A fourth lens with a positive optical power, the object side surface thereof is convex near the optical axis; A fifth lens with a positive optical power, the object side surface thereof is convex, and the image side surface thereof is concave near the optical axis; A sixth lens with a positive optical power, the object side surface thereof is convex near the optical axis, and the image side surface thereof is convex; A seventh lens with a negative optical power, the object side surface thereof is concave; Wherein, the total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 5.5 mm < TTL / Fno < 6.5 mm.

[0005] Further preferably, the total optical length TTL 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: 4 < (TTL × tan(FOV / 2)) / (IH / 2) < 4.5.

[0006] More preferably, 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: 4.9 < IH / EPD < 5.4.

[0007] More preferably, the maximum field of view angle FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 3.1 < FOV / CRA < 3.5.

[0008] More preferably, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively satisfy: 1.9 < TTL / ∑CT < 2.1.

[0009] More preferably, the combined focal length f47 of the fourth lens, the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 1 < f47 / f < 1.2.

[0010] More preferably, the combined focal length f13 of the first lens, the second lens and the third lens and the combined focal length f47 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: -3.5 < f13 / f47 < -2.4.

[0011] More preferably, the focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: -0.7 < f1 / (R1 + R2) < -0.1.

[0012] More preferably, the curvature radius R1 of the object side surface of the first lens and the sagittal height SAGX11 corresponding to the maximum clear aperture semi-diameter at the object side end of the first lens satisfy: 4 < R1 / SAGX11 < 21.

[0013] More preferably, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the clear aperture semi-diameter CSD71 at the object side end of the seventh lens satisfy: 1.2 < CSD11 / CSD71 < 1.6.

[0014] Compared with the prior art, the optical lens provided by the present invention has a small volume through specific surface shape settings and reasonable optical power distribution; it can also achieve a large image height of the lens, can be paired with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration degree of the image; it enables the lens to have a large aperture, and can achieve high-definition imaging even in a dim environment; it can also reasonably correct the overall aberration of the optical lens, making the optical lens have high pixels and improving the imaging quality of the optical lens. 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 description of the embodiments in conjunction with the following 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. Specific Embodiments

[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 the 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 features. 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 drawings, for the sake of clarity, the thickness, dimensions, and shape of the lenses 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 to an exact scale.

[0035] In this document, 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 being 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 "comprises", "comprising", "has", "including" and / or "including having", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not preclude 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 a 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 (including technical and scientific terms) used herein 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, which are, 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.

[0040] In some embodiments, the first lens may have a negative optical power, its object side is convex, and its image side is concave. The second lens may have a negative optical power, its object side may be concave or convex, and its image side is concave. The third lens may have a positive optical power, its object side is convex, and its image side is convex. The fourth lens may have a positive optical power, its object side is convex near the optical axis, and its image side may be concave or convex. The fifth lens may have a positive optical power, its object side is convex, and its image side is concave near the optical axis. The sixth lens may have a positive optical power, its object side is convex near the optical axis, and its image side is convex. The seventh lens may have a negative optical power, its object side is concave, and its image side may be concave or convex.

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

[0042] In some embodiments, the optical lens may further include a filter, and the filter may be 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 total optical length TTL of the optical lens and the f-number Fno of the optical lens satisfy: 5.5mm < TTL / Fno < 6.5mm. By satisfying the above conditional formula and controlling the relationship between the total length and the f-number of the optical lens, it is ensured that the optical lens can meet the requirements of large aperture and miniaturization design, enabling the optical lens to obtain sufficient light transmission in a dim environment and meeting the needs of high-quality and high-definition shooting.

[0044] In some embodiments, the total optical length TTL 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: 4 < (TTL × tan(FOV / 2)) / (IH / 2) < 4.5. Satisfying the above conditional formula can effectively balance the requirements of the image height and the total optical length of the optical lens, effectively limit the length of the optical lens, and is conducive to realizing the miniaturization of the optical lens; at the same time, by controlling the maximum field of view of the optical lens and the true image height corresponding to the maximum field of view, the optical distortion of the optical lens can be controlled, and the overall resolution can be improved.

[0045] In some embodiments, the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.9 < IH / EPD < 5.4. Satisfying the above conditional formula can enable an optical lens with a large image plane to have a relatively large entrance pupil diameter and a relatively high light transmittance, thereby increasing the imaging effect when the optical lens works in a dark environment, and reducing the aberration of the edge field of view.

[0046] In some embodiments, the maximum field of view FOV of the optical lens and the chief ray angle of incidence CRA at the maximum image height of the optical lens satisfy: 3.1 < FOV / CRA < 3.5. Satisfying the above conditional formula, by limiting the ratio of the field of view to the chief ray angle of incidence, the optical lens has a relatively large field of view to meet the requirements of large field of view of electronic devices such as mobile phones and laptop computers. At the same time, by reducing the angle of the chief ray incident on the imaging plane, the photosensitive performance of the photosensitive element can be improved, which is conducive to improving the imaging quality of the optical lens.

[0047] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively satisfy: 1.9 < TTL / ∑CT < 2.1. Satisfying the above conditional formula, by reasonably configuring the total optical length of the optical lens and the sum of the thicknesses of each lens, it helps to achieve high pixel characteristics and improve the imaging quality of the optical lens; at the same time, it can effectively shorten the total optical length of the optical lens and meet the requirements of miniaturization and lightweight design.

[0048] In some embodiments, the combined focal length f47 of the fourth lens, the fifth lens, the sixth lens, and the seventh lens and the effective focal length f of the optical lens satisfy: 1 < f47 / f < 1.2. Satisfying the above conditional formula, by reasonably controlling the ratio of the combined focal length of the fourth lens, the fifth lens, the sixth lens, and the seventh lens to the effective focal length of the optical lens, it is conducive to controlling the angle of light rays exiting the optical lens to reduce the aberration generated by the optical lens, and can also reduce the outer diameter of the fourth lens to the seventh lens to meet the requirements of miniaturization design; it can also correct the influence of the field curvature generated by the front lens on the resolution, and effectively ensure the imaging quality of the optical lens.

[0049] In some embodiments, the combined focal length f13 of the first lens, the second lens, and the third lens and the combined focal length f47 of the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: -3.5 < f13 / f47 < -2.4. Satisfying the above conditional expression, the lens group composed of the first lens, the second lens, and the third lens as a whole has a negative optical power, which is conducive to large-angle light beams entering the optical lens, realizing the large field of view angle requirement of the optical lens and enhancing the brightness of the image plane of the optical lens; while the lens group composed of the fourth lens, the fifth lens, the sixth lens, and the seventh lens as a whole has a positive optical power, which can control the height of the light rays exiting the optical lens, reduce the aberration of the optical lens and the outer diameters of the lenses of the optical lens, and meet the miniaturization design requirements.

[0050] In some embodiments, the focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens, and the curvature radius R2 of the image side surface of the first lens satisfy: -0.7 < f1 / (R1 + R2) < -0.1. Satisfying the above conditional expression can constrain the surface shapes of the object side surface and the image side surface of the first lens, which is conducive to reducing the bending degree of the light rays at the image side surface of the first lens and reducing the astigmatism amount of the optical lens, so as to balance the astigmatism problem brought by the large field of view angle of the optical lens, so that the astigmatism of the optical lens will not be too large while having a large field of view, thereby ensuring that the optical lens has excellent imaging quality.

[0051] In some embodiments, the curvature radius R1 of the object side surface of the first lens and the sagitta SAGX11 corresponding to the maximum clear aperture radius at the object side end of the first lens satisfy: 4 < R1 / SAGX11 < 21. Satisfying the above conditional expression can control the ratio relationship between the curvature radius of the object side surface of the first lens and the sagitta at the maximum effective aperture, provide a negative refractive power for the optical lens, thereby capturing the light rays entering the optical lens at large angles and expanding the field of view angle range of the optical lens.

[0052] In some embodiments, the clear aperture radius CSD11 at the object side end of the first lens and the clear aperture radius CSD71 at the object side end of the seventh lens satisfy: 1.2 < CSD11 / CSD71 < 1.6. Satisfying the above conditional expression can make the optical lens have a smaller aperture size, which is convenient for being mounted on thin and light electronic devices; at the same time, it ensures that the optical lens can collect large-angle light rays, realize large-field-of-view imaging of the optical lens, increase the imaging area of the optical lens, and improve the imaging quality.

[0053] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.4 < IH / f < 2.7. Satisfying the above conditional expression ensures the imaging quality and miniaturization requirements of the optical lens.

[0054] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 0.6 < (IH / 2) / (f × tan(FOV / 2)) < 0.8. By satisfying the above conditional formula, the edge distortion of the optical lens can be controlled, which is beneficial to achieving a larger field of view angle and large image plane characteristics of the optical lens. At the same time, it can effectively increase the proportion of the edge field of view of the optical lens in the entire image plane, enabling the optical lens to meet the high pixel characteristics and improving the imaging quality of the optical lens.

[0055] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.6 < f1 / f < -1.1. By satisfying the above conditional formula, setting the first lens of the optical lens as a negative power lens can capture the light rays entering the optical lens at large angles, expanding the field of view angle range of the optical lens; at the same time, it is also beneficial to reduce the sensitivity of the optical lens and achieve the miniaturized design of the optical lens.

[0056] In some embodiments, the combined focal length f13 of the first lens, the second lens, and the third lens and the effective focal length f of the optical lens satisfy: -3.7 < f13 / f < -2.5. By satisfying the above conditional formula, the value of f13 / f is reasonably set to optimize the power of the first lens, the second lens, and the third lens, reduce the deflection angle of the incident light rays with a large field of view, lower the sensitivity of the optical lens, and can also reduce the head size of the optical lens to meet the small head design requirements.

[0057] In some embodiments, the curvature radius R1 of the object side surface of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: 1.2 < (R1 + R2) / (R1 - R2) < 1.9. By satisfying the above conditional formula, by reasonably defining the shapes of the object side surface and the image side surface of the first lens, the distortion generated by the first lens can be reduced, the distortion correction difficulty of the subsequent lenses can be reduced, and it helps to improve the imaging quality.

[0058] In some embodiments, the sagittal height SAGX11 corresponding to the maximum clear aperture semi-diameter at the object side end of the first lens and the central thickness CT1 of the first lens on the optical axis satisfy: 0.9 < SAGX11 / CT1 < 1.9. By satisfying the above conditional formula, the optical lens meets the small aperture design requirements, which is beneficial to compressing the central field of view of the optical lens and making the imaging quality of the edge field of view better.

[0059] In some embodiments, the central thickness CT3 of the third lens on the optical axis, the central thickness CT4 of the fourth lens on the optical axis, the central thickness CT5 of the fifth lens on the optical axis, and the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively satisfy: 0.3 < (CT3 + CT4 + CT5) / ∑CT < 0.5. Satisfying the above conditional formula and controlling the ratio of the sum of the central thicknesses of the third lens, the fourth lens, and the fifth lens to the sum of the central thicknesses of the first lens to the seventh lens on the optical axis is beneficial to shortening the length of the optical lens, meeting the requirements of miniaturized design, and at the same time is beneficial to the processing and manufacturing of the optical lens and optimizing the configuration of each lens.

[0060] In some embodiments, the optical lens satisfies the conditional formula: 11.5 mm < TTL < 12.6 mm; 3.9 mm < f < 4.4 mm; 115° < FOV < 125°; 1.9 mm < EPD < 2.2 mm; 1.9 < Fno < 2.2; 10.5 mm < IH < 10.7 mm; 3.2 mm < CSD11 < 3.7 mm; 2.8 mm < CSD72 < 3.7 mm; where TTL represents the overall 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, EPD represents the entrance pupil diameter 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, CSD11 represents the clear aperture radius on the object side of the first lens, and CSD72 represents the clear aperture radius on the image side of the seventh lens. Satisfying the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least one or more advantages among miniaturization, large aperture, small aperture, large field of view angle, high pixel, and large image height.

[0061] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected due to the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt an all-plastic lens structure, which not only enables the lens to have excellent imaging performance, but also makes the structure of the lens relatively compact, and can better achieve the balance between the miniaturization of the lens and high image quality.

[0062] 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 the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention can all adopt aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens.

[0063] 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, and H are the coefficients of the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order curved surfaces, respectively.

[0064] The present invention will be further described in multiple embodiments below. In each embodiment, the thickness, curvature radius, and material selection of each lens in the optical lens are partially different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only the preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following embodiments. Any 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.

[0065] Embodiment 1 Please refer to Figure 1 , which shows a schematic structural diagram of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a first lens L1, a second lens L2, a third lens L3, a diaphragm ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0066] Among them, the first lens L1 has a negative optical power. Its object side S1 is a convex surface, and its image side S2 is a concave surface; The second lens L2 has a negative optical power. Its object side S3 is a convex surface near the optical axis, and its image side S4 is a concave surface; The third lens L3 has a positive optical power. Its object side S5 is a convex surface, and its image side S6 is a convex surface; The fourth lens L4 has a positive optical power. Its object side S7 is a convex surface near the optical axis, and its image side S8 is a convex surface; The fifth lens L5 has a positive focal power, its object side S9 is convex, and its image side S10 is concave near the optical axis; The sixth lens L6 has a positive focal power, its object side S11 is convex near the optical axis, and its image side S12 is convex; The seventh lens L7 has a negative focal power, its object side S13 is concave, 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.

[0067] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 all adopt plastic aspherical lenses.

[0068] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0069] 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.

[0070] 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.

[0071] 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 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.

[0072] 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 -0.03 mm to 0.04 mm, indicating that the optical lens 100 can correct the axial aberration better.

[0073] 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 0 - 2 μm, indicating that the optical lens 100 can excellently correct the chromatic aberration of each field of view.

[0074] 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 differences are: the image side surface S8 of the fourth lens L4 is concave near the optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0075] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2 - 1.

[0076] Table 2 - 1 The surface type parameters of the aspherical lenses of the optical lens 200 in Embodiment 2 are shown in Table 2 - 2.

[0077] 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.

[0078] From Figure 6 it can be seen that the astigmatism between the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 200 can well correct astigmatism.

[0079] From Figure 7 it can be seen that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 200 can better correct the axial aberration.

[0080] From Figure 8 it can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within 0 - 2 μm, indicating that the optical lens 200 can excellently correct the chromatic aberration of each field of view.

[0081] Embodiment 3 Please refer to Figure 9, which shows the structural schematic diagram of the optical lens 300 provided in Embodiment 3 of the present invention. Compared with Embodiment 1, the main difference is that the image side S14 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.

[0082] The relevant parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0083] Table 3-1 The surface shape parameters of the aspherical lenses of the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0084] 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.

[0085] 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, indicating that the optical lens 300 can well correct astigmatism.

[0086] From Figure 11 it can be seen that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 300 can better correct the axial aberration.

[0087] From Figure 12 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within 0~2 μm, indicating that the optical lens 300 can excellently correct the chromatic aberration of each field of view.

[0088] Embodiment 4 Please refer to Figure 13 , which shows the structural schematic diagram of the optical lens 400 provided in Embodiment 4 of the present invention. Compared with Embodiment 1, the main difference is that the object side S3 of the second lens L2 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0089] The relevant parameters of each lens in the optical lens 400 in Embodiment 4 are shown in Table 4-1.

[0090] Table 4-1 The surface shape parameters of the aspherical lenses of the optical lens 400 in Embodiment 4 are shown in Table 4-2.

[0091] 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 shown in Figure 14 , Figure 15 , Figure 16 .

[0092] It can be seen from Figure 14 that the astigmatism between the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 400 can correct astigmatism well.

[0093] It can be seen from Figure 15 that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 400 can correct the axial aberration better.

[0094] It can be seen from Figure 16 that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within 0~2 μm, indicating that the optical lens 400 can correct the chromatic aberration of each field of view extremely well.

[0095] 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 maximum field of view angle FOV, the chief ray angle of incidence CRA at the maximum image height, and the values corresponding to each conditional formula in each embodiment.

[0096] Table 5 In summary of the above embodiments, the optical lens provided by the present invention has at least the following advantages: The optical lens provided by the present invention has a small volume through specific surface shape settings and reasonable optical power distribution; it can also achieve a large image height of the lens, can be paired with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration degree of the image; it makes the lens have a large aperture and can achieve high-definition imaging even in a dim environment; it can also reasonably correct the overall aberration of the optical lens, making the optical lens have a high pixel count and improving the imaging quality of the optical lens.

[0097] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. 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 a suitable manner in any one or more embodiments or examples.

[0098] The above-described embodiments merely represent several implementation manners of the present invention. The description 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: Along the optical axis from the object side to the imaging surface, it includes: The first lens has a negative optical power, the object side surface of which is convex, and the image side surface of which is concave; A second lens having negative optical power, whose image side surface is concave; The third lens has positive power, its object side surface is convex, and its image side surface is convex; The fourth lens element has positive refractive power and its object side surface is convex near the optical axis; A fifth lens element having positive refractive power, whose object side surface is convex and whose image side surface is concave near the optical axis; a sixth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is convex; A seventh lens element having negative optical power, whose object side surface is concave; The total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 5.5 mm <TTL / Fno<6.5mm。 2. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 4<(TTL×tan(FOV / 2)) / (IH / 2)<4.

5.

3. The optical lens according to claim 1, characterized in that: The real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.9 <IH / EPD<5.4。 4. The optical lens according to claim 1, characterized in that: The maximum field of view FOV of the optical lens and the chief ray incidence angle CRA at the maximum image height of the optical lens satisfy: 3.1 <FOV / CRA<3.5。 5. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the sum of the center thicknesses of the first lens to the seventh lens on the optical axis ΣCT satisfy: 1.9 <TTL / ∑CT<2.1。 6. The optical lens according to claim 1, characterized in that: The combined focal length f47 of the fourth lens, the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 1 <f47 / f<1.2。 7. The optical lens according to claim 1, characterized in that: The combined focal length f13 of the first lens, the second lens and the third lens and the combined focal length f47 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: -3.5 <f13 / f47<-2.4。 8. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens, and the curvature radius R2 of the image side surface of the first lens satisfy: -0.7 <f1 / (R1+R2)<-0.1。 9. The optical lens according to claim 1, characterized in that: The radius of curvature R1 of the object side of the first lens and the vector height SAGX11 corresponding to the maximum light semi-aperture of the object side end of the first lens satisfy: <R1 / SAGX11<21。 10. The optical lens according to claim 1, characterized in that: The semi-aperture CSD11 of the first lens on the object side and the semi-aperture CSD71 of the seventh lens on the object side satisfy: 1.2 <CSD11 / CSD71<1.6。

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