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 object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex 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 negative focal power, and the object side surface of the fourth lens is a concave surface; the fifth lens has positive focal power, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power; the seventh lens has focal power, and the image side surface of the seventh lens is a concave surface near the optical axis. 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 that can be used for imaging have been rapidly popularized 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 in video conferencing. How to make the imaging lens used in 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] Aiming at the above problems, the purpose 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 of which is convex and the image side surface of which is concave; A second lens with a positive optical power, the object side surface of which is concave and the image side surface of which is convex; A third lens with a positive optical power, the object side surface of which is convex and the image side surface of which is convex; A fourth lens with a negative optical power, the object side surface of which is concave; A fifth lens with a positive optical power, the image side surface of which is convex; A sixth lens with a negative optical power; A seventh lens with an optical power, the image side surface of which is concave near the optical axis; Wherein, the clear aperture diameter CSD11 at the object side end of the first lens satisfies: 2 mm < CSD11 < 3.8 mm; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.3 < TTL / f < 2.6.

[0005] Further 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: 1.8 < TTL / ∑CT < 2.

[0006] Further preferably, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2 ≤ f / EPD ≤ 2.2.

[0007] Further preferably, 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: 0.5 < (IH / 2) / (f × tan(FOV / 2)) < 0.8.

[0008] Further preferably, the combined focal length f37 of the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens and the effective focal length f of the optical lens satisfy: 1.2 < f37 / f < 1.5.

[0009] Further preferably, the focal length f1 of the first lens and the focal length f4 of the fourth lens satisfy: 2.2 < f1 / f4 < 3.5.

[0010] Further preferably, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 3.5 < f2 / f3 < 5.9.

[0011] Further preferably, 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: 0.9 < CSD11 / CSD71 < 1.1.

[0012] Further preferably, the central thickness CT1 of the first lens on the optical axis, the central thickness CT2 of the second lens on the optical axis, and the distance CT12 between the first lens and the second lens on the optical axis satisfy: 1.1 < (CT1 + CT2) / CT12 < 1.6.

[0013] Further preferably, the focal length f5 of the fifth lens, the focal length f3 of the third lens, and the focal length f4 of the fourth lens satisfy: -9 < f5 / (f3 + f4) < -2.

[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 matched 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 high pixels and improving the imaging quality of the optical lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand 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] Figure 17It is a schematic structural diagram of the optical lens in Embodiment 5 of the present invention.

[0032] Figure 18 It is an astigmatism curve graph of the optical lens in Embodiment 5 of the present invention.

[0033] Figure 19 It is an axial aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0034] Figure 20 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0035] Figure 21 It is a schematic structural diagram of the optical lens in Embodiment 6 of the present invention.

[0036] Figure 22 It is an astigmatism curve graph of the optical lens in Embodiment 6 of the present invention.

[0037] Figure 23 It is an axial aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0038] Figure 24 It is a lateral chromatic aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0039] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0040] 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.

[0041] It should be noted that in this specification, the expressions such as first, second, and third are only used to distinguish one feature from another feature and do not represent any limitation on the feature. Therefore, without departing from the teachings of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0042] In the drawings, for ease of illustration, the thickness, size, and shape of the lens have been slightly exaggerated. 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 spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0043] In this text, 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.

[0044] It should also be understood that the terms "comprising", "including", "having", "containing" and / or "including", when used in this specification, denote 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.

[0045] Unless otherwise defined, all terms used herein (including technical and scientific terms) 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.

[0046] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0047] 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, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens.

[0048] In some embodiments, the first lens may have a negative focal power, with its object side being convex and its image side being concave. The second lens may have a positive focal power, with its object side being concave and its image side being convex. The third lens may have a positive focal power, with its object side being convex and its image side being convex. The fourth lens may have a negative focal power, with its object side being concave and its image side being either concave or convex. The fifth lens may have a positive focal power, with its object side being either concave or convex and its image side being convex. The sixth lens may have a negative focal power, with its object side being either concave or convex and its image side being either concave or convex. The seventh lens may have a positive or negative focal power, with its object side being either concave or convex and its image side being concave near the optical axis.

[0049] In some embodiments, the optical lens may further include a diaphragm, which 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 formation.

[0050] In some embodiments, the optical lens may further include a filter, which 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 the normal imaging.

[0051] In some embodiments, the clear aperture diameter CSD11 at the object side end of the first lens satisfies: 2 mm < CSD11 < 3.8 mm. Meeting the above conditional formula enables the optical lens to meet the small-aperture design requirements, while ensuring that the optical lens can receive sufficient light for imaging and ensuring the imaging quality.

[0052] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.3 < TTL / f < 2.6. Meeting the above conditional formula can reasonably configure the ratio of the total optical length to the effective focal length of the optical lens, which is beneficial to realizing the miniaturized design of the optical lens, and thus the optical lens has a smaller volume and lighter weight; and it can ensure that the optical lens has a certain field of view angle and can obtain sufficient object space information.

[0053] 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: 1.8 < TTL / ∑CT < 2. Meeting the above conditional formula and reasonably configuring the total optical length of the optical lens and the sum of the thicknesses of each lens helps to realize the 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 to meet the requirements of miniaturization and lightweight design.

[0054] In some embodiments, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2 ≤ f / EPD ≤ 2.2. By satisfying the above conditional formula, by controlling the ratio of the effective focal length of the optical lens to the entrance pupil diameter, it helps to improve the light receiving ability of the optical lens, obtain as much object space information as possible, and thus obtain imaging information with higher brightness and resolution.

[0055] 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: 0.5 < (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 realizing the characteristics of a large field of view angle and a large image plane 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, enable the optical lens to meet the high pixel characteristics, and improve the imaging quality of the optical lens.

[0056] In some embodiments, the combined focal length f37 of the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens and the effective focal length f of the optical lens satisfy: 1.2 < f37 / f < 1.5. By satisfying the above conditional formula, the proportion of the combined focal length of the third lens to the seventh lens in the effective focal length of the optical lens can be reasonably configured, which is beneficial to the reasonable transition of light between the third lens and the seventh lens. Thus, it is beneficial to reduce the height of the light beam exiting the optical lens, ensure the reduction of the aberration of the optical lens and the effective aperture of each lens from the third lens to the seventh lens, and meet the requirements of miniaturized design.

[0057] In some embodiments, the focal length f1 of the first lens and the focal length f4 of the fourth lens satisfy: 2.2 < f1 / f4 < 3.5. By satisfying the above conditional formula, the effective focal lengths of the first lens and the fourth lens can be reasonably distributed, thereby further expanding the field of view angle of the optical lens and effectively correcting the distortion of the optical lens.

[0058] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 3.5 < f2 / f3 < 5.9. By satisfying the above conditional formula, by reasonably configuring the ratio of the focal lengths of the second lens and the third lens, the field of view angle of the optical lens can be effectively expanded, which is beneficial to compressing the total length of the optical lens and realizing the characteristic of being thin.

[0059] In some embodiments, the clear aperture diameter CSD11 of the object side end of the first lens and the clear aperture diameter CSD71 of the object side end of the seventh lens satisfy: 0.9 < CSD11 / CSD71 < 1.1. By satisfying the above conditional formula, the optical lens can have a smaller aperture size, which is convenient for being mounted on a thin and light electronic device; at the same time, it ensures that the optical lens can collect light at large angles, realizes large field of view imaging of the optical lens, increases the imaging area of the optical lens, and improves the imaging quality.

[0060] In some embodiments, the central thickness CT1 of the first lens on the optical axis, the central thickness CT2 of the second lens on the optical axis, and the distance CT12 between the first lens and the second lens on the optical axis satisfy: 1.1 < (CT1 + CT2) / CT12 < 1.6. By satisfying the above conditional formula, the distortion of the marginal field of view of the optical lens can be effectively regulated, which is beneficial to controlling the distortion amount of the marginal field of view within a reasonable range.

[0061] In some embodiments, the focal length f5 of the fifth lens, the focal length f3 of the third lens, and the focal length f4 of the fourth lens satisfy: -9 < f5 / (f3 + f4) < -2. By satisfying the above conditional formula, it is beneficial to control the exit light angle of the light beam when it exits the fifth lens, thereby reducing the light angle of the marginal field of view light beam entering the sixth lens, so as to reduce the high-order aberration in the optical lens and the working aperture of the subsequent lens; on the other hand, it can correct the field curvature generated by the first lens and the second lens, thereby reducing the influence on the resolution of the optical lens.

[0062] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -5.5 < f1 / f < -3.5. By satisfying the above conditional formula, setting the first lens of the optical lens as a lens with a negative optical power can capture the light rays entering the optical lens at large angles, expand 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 realize the miniaturized design of the optical lens.

[0063] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 2.8 < f2 / f < 3. By satisfying the above conditional formula, it is beneficial to cooperate with the first lens to make light rays at large angles enter the optical lens, thereby expanding the field of view angle of the optical lens, and at the same time, it is also beneficial to correct the astigmatism and chromatic aberration of the optical lens, and improve the imaging quality of the optical lens.

[0064] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f3 / f < 0.8. By satisfying the above conditional formula, by setting the third lens with a positive optical power and limiting the ratio of the focal length of the third lens to the effective focal length of the optical lens, it is beneficial to adjust the light ray trend from the first lens and the second lens, so that the optical lens has certain characteristics of a large field of view angle, low sensitivity and miniaturization.

[0065] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the sagitta SAGX11 corresponding to the maximum clear aperture semi-diameter at the object side end of the first lens satisfy: 2.8 < CSD11 / SACX11 < 3.3. Meeting the above conditional formula, the clear aperture semi-diameter at the object side end of the first lens enables the optical lens to meet 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.

[0066] In some embodiments, the radius of curvature R14 of the image side surface of the seventh lens and the central thickness CT7 of the seventh lens on the optical axis satisfy: 2.5 < R14 / CT7 < 8.5. Meeting the above conditional formula can effectively control the incident angle of light on the seventh lens and improve the imaging quality of the optical lens.

[0067] In some embodiments, the distance CT23 between the second lens and the third lens on the optical axis and the total optical length TTL of the optical lens satisfy: 0.02 < CT23 / TTL < 0.07. Meeting the above conditional formula, by reasonably restricting the air gap between the second and third lenses, the deflection of light can tend to be slow, which is beneficial to reducing the sensitivity of the optical lens.

[0068] In some embodiments, the optical lens satisfies the conditional formula: 11.2 mm < TTL < 11.9 mm; 4.5 mm < f < 5 mm; 110° < FOV < 120°; 2 mm < EPD < 2.5 mm; 2 ≤ Fno ≤ 2.2; 9 mm < IH < 11 mm; 2 mm < CSD11 < 3.5 mm; 2 mm < CSD12 < 2.5 mm; where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, Fno represents the f-number 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 semi-diameter at the object side end of the first lens, and CSD12 represents the clear aperture semi-diameter at the image side end of the first lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least one or more advantages among miniaturization, large aperture, small aperture, large field of view angle, high pixel, and large image height.

[0069] 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. On the other hand, when the lens material is glass, due to the low dispersion characteristic of the glass itself, the geometric chromatic aberration of the optical system can be effectively corrected. 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 of miniaturization and high image quality of the lens.

[0070] 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 be 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.

[0071] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equation: ; where z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the conic coefficient, and B, C, D, E, F, G, H are the conic coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order, respectively.

[0072] 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 somewhat 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.

[0073] Embodiment 1 Please refer to Figure 1 , which shows a schematic structural diagram of an optical lens 100 provided in Embodiment 1 of the present invention. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a first lens L1, a second lens L2, a diaphragm 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.

[0074] Among them, the first lens L1 has a negative optical power. Its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface; The second lens L2 has a positive optical power. Its object side surface S3 is a concave surface, and its image side surface S4 is a convex surface; The third lens L3 has a positive optical power. Its object side surface S5 is a convex surface, and its image side surface S6 is a convex surface; The fourth lens L4 has a negative optical power. Its object side surface S7 is a concave surface, and its image side surface S8 is a convex surface; The fifth lens L5 has a positive focal power, its object side S9 is concave, and its image side S10 is convex; The sixth lens L6 has a negative focal power, its object side S11 is concave, and its image side S12 is concave; The seventh lens L7 has a negative focal power, its object side S13 is convex near the optical axis, and its image side S14 is concave near the optical axis; Both the object side S15 and the image side S16 of the filter G1 are flat; The imaging surface S17 is flat.

[0075] 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 are all plastic aspherical lenses.

[0076] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0077] 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.

[0078] 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.

[0079] 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 well correct astigmatism.

[0080] 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 -0.04 mm to 0.02 mm, indicating that the optical lens 100 can better correct the axial aberration.

[0081] 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 plane. 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 ±2 μm, indicating that the optical lens 100 can excellently correct the chromatic aberration of each field of view.

[0082] 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 as follows: the image side surface S12 of the sixth lens L6 is convex near the optical axis; the object side surface S13 of the seventh lens L7 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0083] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0084] 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.

[0085] 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.

[0086] 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 the astigmatism.

[0087] From Figure 7 it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 200 can preferably correct the axial aberration.

[0088] From Figure 8 it can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 200 can excellently correct the chromatic aberration of each field of view.

[0089] 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 differences are as follows: the image side S8 of the fourth lens L4 is concave near the optical axis; the object side S9 of the fifth lens L5 is convex near the optical axis; the object side S13 of the seventh lens L7 is concave near the optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0090] The relevant parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0091] Table 3-1 The surface type parameters of the aspherical lenses in the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0092] 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.

[0093] From Figure 10 it can be seen that the astigmatism between the meridional image plane and the sagittal image plane is controlled within ±0.2 mm, indicating that the optical lens 300 can correct astigmatism well.

[0094] From Figure 11 it can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can correct the axial aberration better.

[0095] From Figure 12 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 300 can correct the chromatic aberration of each field of view extremely well.

[0096] 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 differences are as follows: the seventh lens L7 has a positive optical power; the image side S8 of the fourth lens L4 is concave; the object side S9 of the fifth lens L5 is convex; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0097] The relevant parameters of each lens in the optical lens 400 in Embodiment 4 are shown in Table 4-1.

[0098] Table 4-1 The surface type parameters of the aspherical lens of the optical lens 400 in Embodiment 4 are shown in Table 4-2.

[0099] Table 4-2 In this embodiment, the astigmatism curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 400 are respectively as Figure 14 , Figure 15 , Figure 16 shown.

[0100] From Figure 14 , 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 400 can correct astigmatism well.

[0101] From Figure 15 , it can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 400 can correct the axial aberration better.

[0102] From Figure 16 , it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 400 can correct the chromatic aberration of each field of view extremely well.

[0103] Embodiment 5 Please refer to Figure 17 , which shows the structural schematic diagram of the optical lens 500 provided in Embodiment 5 of the present invention. Compared with Embodiment 1, the main differences are as follows: The seventh lens L7 has a positive optical power; the object side surface S11 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0104] The relevant parameters of each lens in the optical lens 500 in Embodiment 5 are shown in Table 5-1.

[0105] Table 5-1 The surface type parameters of the aspherical lens of the optical lens 500 in Embodiment 5 are shown in Table 5-2.

[0106] Table 5-2 In this embodiment, the astigmatism curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 500 are respectively as Figure 18 , Figure 19 , Figure 20 shown.

[0107] From Figure 18It can be seen that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 500 can correct astigmatism well.

[0108] From Figure 19 it can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 500 can correct the axial aberration well.

[0109] From Figure 20 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 500 can correct the chromatic aberration of each field of view extremely well.

[0110] Embodiment 6 Please refer to Figure 21 , which shows the structural schematic diagram of the optical lens 600 provided in Embodiment 6 of the present invention. Compared with Embodiment 1, the main differences are: the seventh lens L7 has a positive optical power; the object side surface S11 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0111] The relevant parameters of each lens in the optical lens 600 in Embodiment 6 are shown in Table 6-1.

[0112] Table 6-1 The surface type parameters of the aspherical lenses of the optical lens 600 in Embodiment 6 are shown in Table 6-2.

[0113] Table 6-2 In this embodiment, the astigmatism curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 600 are respectively as Figure 22 , Figure 23 , Figure 24 shown.

[0114] From Figure 22 it can be seen that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 600 can correct astigmatism well.

[0115] From Figure 23 it can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 600 can correct the axial aberration well.

[0116] From Figure 24 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 600 can correct the chromatic aberration of each field of view extremely well.

[0117] Please refer to Table 7 for 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 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.

[0118] Table 7 Combining 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, through specific surface shape settings and reasonable optical power distribution, makes the lens have a small volume; 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 resolution of the lens and the detail restoration of the image; makes the lens have a large aperture, and high-definition imaging can be achieved 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.

[0119] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0120] The above embodiments merely represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting 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 should be subject to the appended claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: It successively includes from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose object side surface is convex and whose image side surface is concave; A second lens with a positive optical power, whose object side surface is concave and whose image side surface is convex; A third lens with a positive optical power, whose object side surface is convex and whose image side surface is convex; A fourth lens with a negative optical power, whose object side surface is concave; A fifth lens with a positive optical power, whose image side surface is convex; A sixth lens with a negative optical power; A seventh lens with an optical power, whose image side surface is concave near the optical axis; Wherein, the clear aperture semi-diameter CSD11 at the object side end of the first lens satisfies: 2mm < CSD11 < 3.8mm; The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.3 < TTL / f < 2.

6.

2. The optical lens according to claim 1, characterized in that: 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: 1.8 < TTL / ∑CT < 2.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2 ≤ f / EPD ≤ 2.

2.

4. 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 effective focal length f of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 0.5 < (IH / 2) / (f×tan(FOV / 2)) < 0.

8.

5. The optical lens according to claim 1, characterized in that: The combined focal length f37 of the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 1.2 < f37 / f < 1.

5.

6. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the focal length f4 of the fourth lens satisfy: 2.2 < f1 / f4 < 3.

5.

7. 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: 3.5 < f2 / f3 < 5.

9.

8. The optical lens according to claim 1, characterized in that: 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: 0.9 < CSD11 / CSD71 < 1.

1.

9. The optical lens according to claim 1, characterized in that: The central thickness CT1 of the first lens on the optical axis, the central thickness CT2 of the second lens on the optical axis and the distance CT12 between the first lens and the second lens on the optical axis satisfy: 1.1 < (CT1 + CT2) / CT12 < 1.

6.

10. The optical lens according to claim 1, characterized in that: The focal length f5 of the fifth lens, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -9 < f5 / (f3 + f4) < -2.

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