Optical lens

Abstract

The present invention provides an optical lens, which has a total of seven lenses and sequentially includes, along the optical axis from the object side to the imaging surface: a first lens with a negative optical power, whose object side surface is concave and whose image side surface is convex; a second lens with a positive optical power, whose object side surface and image side surface are both convex; a third lens with a positive optical power, whose object side surface and image side surface are both convex; a fourth lens with a negative optical power, whose object side surface and image side surface are both concave; a fifth lens with a positive optical power, whose object side surface is convex and whose image side surface is concave; a sixth lens with a positive optical power, whose object side surface is convex; a seventh lens with a negative optical power, whose image side surface is concave; the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: -0.91 < (R9 - R10) / (R9 + R10) < -0.69. The optical lens provided by the present invention has one or more advantages such as long focal length, large aperture, and high imaging quality through specific surface shape matching and reasonable optical power distribution.

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 continuous improvement of people's requirements for driving experience, on-vehicle application optical lenses are increasingly used in intelligent driving, and the status of on-vehicle optical lenses in the automotive-related industry is constantly rising.

[0003] Advanced Driver Assistance Systems (ADAS) play an important role in intelligent driving. It collects environmental information through various lenses and sensors to ensure the driving safety of the driver. In addition to requiring the optical lens to have a thin, light, short, and small shape and have characteristics such as high pixels and high resolution, the existing ADAS system lenses also require the optical lens to be able to clearly image under low illuminance conditions. Therefore, it is necessary to develop an optical lens with good imaging effect. Summary of the Invention

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

[0005] The technical solution adopted by the present invention is as follows:

[0006] An optical lens, comprising a total of seven lenses, which in turn include, along the optical axis from the object side to the imaging surface:

[0007] A first lens with negative optical power, the object side surface of which is concave and the image side surface of which is convex;

[0008] A second lens with positive optical power, the object side surface and the image side surface of which are both convex;

[0009] A third lens with positive optical power, the object side surface and the image side surface of which are both convex;

[0010] A fourth lens with negative optical power, the object side surface and the image side surface of which are both concave;

[0011] A fifth lens with positive optical power, the object side surface of which is convex and the image side surface of which is concave;

[0012] A sixth lens with positive optical power, the object side surface of which is convex;

[0013] A seventh lens with negative optical power, the image side surface of which is concave;

[0014] Wherein, the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: -0.91 < (R9 - R10) / (R9 + R10) < -0.69.

[0015] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2 < TTL / f < 2.9; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 4 < TTL / IH < 4.9.

[0016] 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: 0.96 < (IH / 2) / (f × Tan(FOV / 2)) < 1.01; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 0.5 / ° < TTL / (IH / 2) / (FOV / 2) < 0.62 / °.

[0017] Further preferably, 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: 0.51 < IH / f < 0.59; the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.23 < BFL / f < 0.36.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -5.2 < f1 / f < -3.5; the object-side curvature radius R1 of the first lens and the effective focal length f of the optical lens satisfy: -1.15 < R1 / f < -0.95; the image-side curvature radius R2 of the first lens and the effective focal length f of the optical lens satisfy: -2.15 < R2 / f < -1.6.

[0019] 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; the object-side curvature radius R3 of the second lens and the effective focal length f of the optical lens satisfy: 1.3 < R3 / f < 1.7; the image-side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -50 < R4 / f < -3.9.

[0020] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.74 < f3 / f < 0.99; the object-side curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: 0.59 < R5 / f < 0.71; the image-side curvature radius R6 of the third lens and the effective focal length f of the optical lens satisfy: -2.3 < R6 / f < -1.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.05 < f5 / f < 2.15; the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.5 < R9 / f < 1.15; the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 5.4 < R10 / f < 21.

[0022] Further preferably, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 4 < f1234 / f567 < 22.

[0023] Further preferably, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: -0.33 < (R1 - R2) / (R1 + R2) < -0.2.

[0024] Further preferably, the clear aperture semi-diameter d9 of the object side surface of the fifth lens and the sagittal height Sag9 of the object side surface of the fifth lens satisfy: 0.07 < Sag9 / d9 < 0.31; the clear aperture semi-diameter d10 of the image side surface of the fifth lens and the sagittal height Sag10 of the image side surface of the fifth lens satisfy: 0 < Sag10 / d10 < 0.03.

[0025] The optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and enable the lens to have one or more advantages such as long focal length, large aperture, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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, wherein:

[0027] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 2 is a field curvature curve graph of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 3 is an F-Tan(Theta) distortion curve graph of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 4 is an axial aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 5 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0032] Figure 6 It is the structural schematic diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 7 It is the field curvature curve graph of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 8 It is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 9 It is the axial aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0036] Figure 10 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0037] Figure 11 It is the structural schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 12 It is the field curvature curve graph of the optical lens in Embodiment 3 of the present invention.

[0039] Figure 13 It is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 3 of the present invention.

[0040] Figure 14 It is the axial aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0041] Figure 15 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0042] Figure 16 It is the structural schematic diagram of the optical lens in Embodiment 4 of the present invention.

[0043] Figure 17 It is the field curvature curve graph of the optical lens in Embodiment 4 of the present invention.

[0044] Figure 18 It is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 4 of the present invention.

[0045] Figure 19 It is the axial aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0046] Figure 20 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0047] Figure 21 This is a schematic structural diagram of the optical lens in Embodiment 5 of the present invention.

[0048] Figure 22 This is the field curvature curve graph of the optical lens in Embodiment 5 of the present invention.

[0049] Figure 23 This is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 5 of the present invention.

[0050] Figure 24 This is the axial aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0051] Figure 25 This is the lateral chromatic aberration curve graph of the optical lens in Embodiment 5 of the present invention.

[0052] Figure 26 This is a schematic structural diagram of the optical lens in Embodiment 6 of the present invention.

[0053] Figure 27 This is the field curvature curve graph of the optical lens in Embodiment 6 of the present invention.

[0054] Figure 28 This is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 6 of the present invention.

[0055] Figure 29 This is the axial aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0056] Figure 30 This is the lateral chromatic aberration curve graph of the optical lens in Embodiment 6 of the present invention.

[0057] Figure 31 This is a schematic structural diagram of the optical lens in Embodiment 7 of the present invention.

[0058] Figure 32 This is the field curvature curve graph of the optical lens in Embodiment 7 of the present invention.

[0059] Figure 33 This is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 7 of the present invention.

[0060] Figure 34 This is the axial aberration curve graph of the optical lens in Embodiment 7 of the present invention.

[0061] Figure 35 This is the lateral chromatic aberration curve graph of the optical lens in Embodiment 7 of the present invention.

[0062] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0063] To better understand the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of embodiments of the present application and do not limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0064] 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.

[0065] In the drawings, for ease of illustration, the thickness, size, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn to an exact scale.

[0066] 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.

[0067] It should also be understood that the terms "comprise", "comprising", "have", "including" and / or "containing", 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 individual elements in the list. In addition, when describing 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.

[0068] Unless otherwise defined, all terms (including technical and scientific terms) used herein 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.

[0069] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments 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.

[0070] The optical lens provided by the embodiment of the present invention is composed 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.

[0071] In some embodiments, the first lens may have a negative optical power, its object side is concave, and its image side is convex. The second lens may have a positive optical power, and both its object side and image side are convex. The third lens may have a positive optical power, and both its object side and image side are convex. The fourth lens may have a negative optical power, and both its object side and image side are concave. The fifth lens may have a positive optical power, its object side is convex, and its image side is concave. The sixth lens may have a positive optical power, its object side is convex, and its image side may be concave or convex. The seventh lens may have a negative optical power, its object side may be concave or convex, and its image side is concave.

[0072] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the fourth lens and the fifth lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image. In addition, when the diaphragm is located between the fourth lens and the fifth lens, the diaphragm can reasonably distribute the functions of the first lens to the seventh lens. For example, the first lens, the second lens, the third lens, and the fourth lens can be used to receive light to a greater extent, and the fifth lens to the seventh lens can be used to correct aberrations, which is beneficial to balancing the structure of the entire optical system. In addition, when the diaphragm is located between the fourth lens and the fifth lens, it is convenient to correct the diaphragm aberration.

[0073] In some embodiments, the optical lens may further include a filter and a protective glass, and the filter and the protective glass may be sequentially arranged along the optical axis 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. The protective glass plays a role in protecting the optical lens, preventing the photosensitive chip from being damaged, and can improve the anti-impact and scratch-resistant capabilities of the optical lens, while having almost no impact on the imaging quality of the optical lens.

[0074] In some embodiments, the third lens and the fourth lens may be glued together to form a cemented lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0075] In some embodiments, the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: -0.91 < (R9 - R10) / (R9 + R10) < -0.69. Satisfying the above range is beneficial to the smooth transition of light, can effectively correct the distortion of the edge field of view, reduce the deformation degree of the edge of the captured image, and improve the image quality.

[0076] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2 < TTL / f < 2.9. Satisfying the above range can effectively limit the length of the lens while achieving a long focal length, which is beneficial to the miniaturization of the optical lens. More specifically, 2.23 < TTL / f < 2.79.

[0077] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 4 < TTL / IH < 4.9. Satisfying the above range can ensure a larger image plane under the condition of the same total lens length, can match a larger-sized imaging chip to achieve high-definition imaging, and can better achieve the balance between the small total length and the large image plane of the lens. More specifically, 4.04 < TTL / IH < 4.83.

[0078] 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: 0.96 < (IH / 2) / (f × Tan(FOV / 2)) < 1.01. Satisfying the above range can control the optical lens to have a small distortion and improve the imaging quality.

[0079] In some embodiments, the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 0.5 / ° < TTL / (IH / 2) / (FOV / 2) < 0.62 / °. Satisfying the above range can limit the length of the optical lens under the condition of the same imaging area and the same field of view angle, and achieve the miniaturization of the optical lens.

[0080] 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: 0.51 < IH / f < 0.59. Satisfying the above range can control the image height and focal length of the optical lens within a reasonable range, which helps the optical lens to have the characteristic of a large image plane and improve the imaging quality.

[0081] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.23 < BFL / f < 0.36. Satisfying the above range defines that the optical lens has an appropriate back focus, facilitating the reasonable arrangement of the positions of the respective lenses, and at the same time reducing the processing and assembly difficulty.

[0082] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -5.2 < f1 / f < -3.5; the object-side curvature radius R1 of the first lens and the effective focal length f of the optical lens satisfy: -1.15 < R1 / f < -0.95; the image-side curvature radius R2 of the first lens and the effective focal length f of the optical lens satisfy: -2.15 < R2 / f < -1.6. Satisfying the above range, by setting the first lens to have a negative refractive power and an appropriate surface shape, it is beneficial for the first lens to receive a larger angle of light and collect as much light as possible into the rear optical system, achieving a large field of view while increasing the light flux. More specifically, -5.2 < f1 / f < -3.5; -1.15 < R1 / f < -0.95; -2.15 < R2 / f < -1.6.

[0083] 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; the object-side curvature radius R3 of the second lens and the effective focal length f of the optical lens satisfy: 1.3 < R3 / f < 1.7; the image-side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -50 < R4 / f < -3.9. Satisfying the above range defines that the second lens has an appropriate positive optical power and an appropriate surface shape, has the effect of converging light, reducing the height of peripheral light, facilitating the reduction of the aperture of the rear lens, and at the same time being beneficial for balancing aberrations and improving resolution. More specifically, 1.53 < f2 / f < 1.99; 1.31 < R3 / f < 1.68; -49.95 < R4 / f < -3.93.

[0084] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.74 < f3 / f < 0.99; the object-side curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: 0.59 < R5 / f < 0.71; the image-side curvature radius R6 of the third lens and the effective focal length f of the optical lens satisfy: -2.3 < R6 / f < -1. Satisfying the above range defines that the third lens has an appropriate positive optical power and an appropriate surface shape, and the light is further converged. And gluing the third lens with positive optical power and the fourth lens with negative optical power is beneficial for the light to enter the rear lens smoothly, can adjust the optical path difference between different fields of view, and improve the resolution. More specifically, -2.24 < R6 / f < -1.03.

[0085] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.05 < f5 / f < 2.15; the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.5 < R9 / f < 1.15; the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 5.4 < R10 / f < 21. Meeting the above ranges and setting the fifth lens to have positive refractive power and a suitable surface shape is beneficial to converging light while correcting the field curvature and distortion of the optical lens, and improving the imaging quality of the optical lens. More specifically, 1.07 < f5 / f < 2.12; 0.5 < R9 / f < 1.12; 5.44 < R10 / f < 20.8.

[0086] In some embodiments, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 4 < f1234 / f567 < 22. Meeting the above ranges and reasonably setting the relationship between the lens groups before and after the aperture is beneficial to balancing various aberrations of the system and improving the overall imaging quality. More specifically, 4.05 < f1234 / f567 < 21.8.

[0087] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: -0.33 < (R1 - R2) / (R1 + R2) < -0.2. Meeting the above ranges can make the collected light enter the rear optical system in a divergent form as much as possible, and at the same time effectively reduce the angle between the light incident on the edge field of view and the object side surface of the first lens, and improve the relative illumination of the edge of the overall lens.

[0088] In some embodiments, the clear aperture semi-diameter d9 of the object side surface of the fifth lens and the sagittal height Sag9 of the clear aperture of the object side surface of the fifth lens satisfy: 0.07 < Sag9 / d9 < 0.31; the clear aperture semi-diameter d10 of the image side surface of the fifth lens and the sagittal height Sag10 of the clear aperture of the image side surface of the fifth lens satisfy: 0 < Sag10 / d10 < 0.03. Meeting the above ranges helps to control the trend of the light in the edge field of view and highlight the detailed information of the central field of view of the optical lens.

[0089] In some embodiments, the maximum field of view FOV of the optical lens and the f-number Fno of the optical lens satisfy: 17° < FOV / Fno < 21°. Meeting the above ranges and defining that the optical lens has a suitable field of view and f-number can collect light at large angles and obtain good imaging quality. More specifically, 17.13° < FOV / Fno < 20.01°.

[0090] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 0.8 < IH / EPD < 1.05. Satisfying the above range can increase the width of the light beam incident on the optical lens, improve the brightness of the optical lens at the image plane, and avoid the generation of vignetting. More specifically, 0.82 < IH / EPD < 1.05.

[0091] 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 along the optical axis satisfy: 0.54 < ∑CT / TTL < 0.68. Satisfying the above range can effectively compress the total length of the optical lens, and is beneficial to the structural design and production process of the optical lens.

[0092] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -0.54 < f4 / f < -0.4. Satisfying the above range, which limits the fourth lens to have an appropriate negative optical power, can diverge the light rays emitted by the third lens, make the light rays in the marginal field of view show an upward trend, is beneficial to the image points on the imaging plane to be away from the optical axis, is beneficial to achieve the effect of matching with a large chip, obtain a larger picture, can effectively eliminate aberrations, and improve the resolution ability of the optical lens.

[0093] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.63 < f6 / f < 1.75. Satisfying the above range, which limits the sixth lens to have a positive optical power, is beneficial to the convergence of light rays, makes the light ray trend transition smoothly to the rear, reduces the height of the light rays incident on the rear, slows down the upward trend of the light rays, avoids the light energy loss caused by the excessive main ray angle of the large field of view light rays reaching the imaging plane, is beneficial to improving the illuminance of the marginal field of view, and is beneficial to achieving a short total optical length. More specifically, 0.63 < f6 / f < 1.71.

[0094] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -3.3 < f7 / f < -0.5. Satisfying the above range can effectively balance various aberrations generated by the front lens group, and is beneficial to increasing the divergence degree of light rays, increasing the area of light rays entering the imaging plane, realizing large target surface imaging of the lens, and improving the imaging quality of the optical lens. More specifically, -3.28 < f7 / f < -0.5.

[0095] In some embodiments, the optical lens satisfies the following conditional expressions: 10 mm < f < 14 mm; 29° < FOV < 34°; 5.5 mm < EPD < 8.5 mm; 27 mm < TTL < 32 mm; 1.5 < Fno < 1.9; 5.5 mm < IH < 7 mm; 23° < CRA < 35°; 3.1 mm < BFL < 3.7 mm. In the above conditional expressions, 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, TTL represents the overall optical length of the optical lens, FNO represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray angle of incidence of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as a large target surface, a large aperture, and a long focal length characteristic. More specifically, 10.41 mm < f < 13.19 mm; 5.78 mm < EPD < 8.25 mm; 27.93 mm < TTL < 31.31 mm; 1.59 < Fno < 1.81; 23.93° < CRA < 34.44°; 3.17 mm < BFL < 3.64 mm; 29.9° < FOV < 33.1°; 5.99 mm < IH < 6.92 mm.

[0096] 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, 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-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0097] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical lens 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 adopt spherical lenses.

[0098] The present invention will be further described in multiple embodiments below. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are somewhat different. For specific differences, 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 other changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0099] Embodiment 1

[0100] Please refer to Figure 1 , which shows a schematic structural diagram of an optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 sequentially includes, along the optical axis from the object side to the imaging surface: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0101] Among them, the first lens L1 has a negative optical power. Its object side surface S1 is a concave surface, and its image side surface S2 is a convex surface;

[0102] The second lens L2 has a positive optical power. Its object side surface S3 is a convex surface, and its image side surface S4 is a convex surface;

[0103] The third lens L3 has a positive optical power. Its object side surface S5 and image side surface S6 are both convex surfaces;

[0104] The fourth lens L4 has a negative optical power. Its object side surface S6 is a concave surface, and its image side surface S7 is a concave surface;

[0105] The third lens L3 and the fourth lens L4 form a cemented lens group with a negative optical power, that is, the cemented surface of the image side surface of the third lens L3 and the object side surface of the fourth lens L4 is S6;

[0106] The fifth lens L5 has a positive optical power. Its object side surface S8 is a convex surface, and its image side surface S9 is a concave surface;

[0107] The sixth lens L6 has a positive optical power. Its object side surface S10 is a convex surface, and its image side surface S11 is a concave surface;

[0108] The seventh lens L7 has a negative optical power. Its object side surface S12 is a convex surface, and its image side surface S13 is a concave surface;

[0109] Both the object side surface S14 and the image side surface S15 of the filter G1 are flat surfaces;

[0110] Both the object side surface S16 and the image side surface S17 of the protective glass G2 are flat surfaces;

[0111] The imaging surface S18 is a plane.

[0112] 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 made of glass spherical lenses.

[0113] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1.

[0114] Table 1

[0115]

[0116] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve, the axial aberration curve, and the lateral chromatic aberration curve of the optical lens 100 are respectively as Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0117] Figure 2 shows the field curvature curve of Embodiment 1, which represents the bending degree of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens can well correct the field curvature.

[0118] Figure 3 shows the F-Tan(Theta) distortion curve of Embodiment 1, which represents the F-Tan(Theta) distortion of light rays with different wavelengths at different image heights on the imaging surface. The horizontal axis represents the F-Tan(Theta) distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tan(Theta) distortion of the optical lens is controlled within -1% to 0, indicating that the optical lens can better correct the distortion.

[0119] Figure 4 shows the axial aberration curve of Embodiment 1, 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 to 0.04 mm, indicating that the optical lens can better correct the axial aberration.

[0120] Figure 5The vertical chromatic aberration curve diagram of Embodiment 1 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.55 μm) at different image heights on the imaging surface. The horizontal axis represents the vertical chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3 μm to 1 μm, indicating that the optical lens can excellently correct chromatic aberration.

[0121] Embodiment 2

[0122] Please refer to Figure 6 , which shows the structural schematic diagram of the optical lens 200 provided in Embodiment 2 of the present invention. Compared with Embodiment 1, the main difference is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0123] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2.

[0124] Table 2

[0125]

[0126] In this embodiment, the field curvature curve diagram, F-Tan(Theta) distortion curve, axial aberration curve diagram, and vertical chromatic aberration curve diagram of the optical lens 200 are respectively as Figure 7 , Figure 8 , Figure 9 , Figure 10 shown.

[0127] From Figure 7 it can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.03 mm, indicating that the optical lens 200 can well correct the field curvature.

[0128] From Figure 8 it can be seen that the F-Tan(Theta) distortion of the optical lens 200 is controlled within -1% to 0, indicating that the optical lens 200 can better correct the distortion.

[0129] From Figure 9 it can be seen that the offset of the axial aberration is controlled within 0 to 0.04 mm, indicating that the optical lens 200 can better correct the axial aberration.

[0130] From Figure 10 it can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3 μm to 1 μm, indicating that the optical lens 200 can excellently correct the chromatic aberration.

[0131] Embodiment 3

[0132] Please refer to Figure 11, 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 S11 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0133] The relevant parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3.

[0134] Table 3

[0135]

[0136] In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve, axial aberration curve graph, lateral chromatic aberration curve graph, and MTF curve graph of the optical lens 300 are respectively as Figure 12 , Figure 13 , Figure 14 , Figure 15 shown.

[0137] From Figure 12 , it can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 300 can correct the field curvature well.

[0138] From Figure 13 , it can be seen that the F-Tan(Theta) distortion of the optical lens 300 is controlled within -2% to 0, indicating that the optical lens 300 can correct the distortion better.

[0139] From Figure 14 , it can be seen that the offset of the axial aberration is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 300 can correct the axial aberration better.

[0140] From Figure 15 , it can be seen that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -2 μm to 1 μm, indicating that the optical lens 300 can correct the chromatic aberration extremely well.

[0141] Embodiment 4

[0142] Please refer to Figure 16 , 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 image side S11 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0143] The relevant parameters of each lens in the optical lens 400 in Embodiment 4 are shown in Table 4.

[0144] Table 4

[0145]

[0146] In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 400 are respectively as shown in Figure 17 , Figure 18 , Figure 19 , Figure 20 .

[0147] It can be seen from Figure 17 that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.03 mm, indicating that the optical lens 400 can correct the field curvature well.

[0148] It can be seen from Figure 18 that the F-Tan(Theta) distortion of the optical lens 400 is controlled within -3% to 0, indicating that the optical lens 400 can correct the distortion better.

[0149] It can be seen from Figure 19 that the offset of the axial aberration is controlled within -0.01 mm to 0.03 mm, indicating that the optical lens 400 can correct the axial aberration better.

[0150] It can be seen from Figure 20 that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -2 μm to 1 μm, indicating that the optical lens 400 can correct the chromatic aberration extremely well.

[0151] Embodiment 5

[0152] Please refer to Figure 21 , 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 image side surface S11 of the sixth lens L6 is a convex surface; the object side surface S12 of the seventh lens L7 is a concave surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0153] The relevant parameters of each lens in the optical lens 500 in Embodiment 5 are shown in Table 5.

[0154] Table 5

[0155]

[0156] In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve graph, axial aberration curve graph, lateral chromatic aberration curve graph, and MTF curve graph of the optical lens 500 are respectively as shown in Figure 22 , Figure 23 , Figure 24 , Figure 25 .

[0157] It can be seen from Figure 22 that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 500 can well correct the field curvature.

[0158] It can be seen from Figure 23 that the F-Tan(Theta) distortion of the optical lens 500 is controlled within -4% to 0, indicating that the optical lens 500 can better correct the distortion.

[0159] It can be seen from Figure 24 that the offset of the axial aberration is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 500 can better correct the axial aberration.

[0160] It can be seen from Figure 25 that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1 μm to 1 μm, indicating that the optical lens 500 can excellently correct the chromatic aberration.

[0161] Embodiment 6

[0162] Please refer to Figure 26 , 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 that: the image side surface S11 of the sixth lens L6 is a convex surface; the object side surface S12 of the seventh lens L7 is a concave surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0163] The relevant parameters of each lens in the optical lens 600 in Embodiment 6 are shown in Table 6.

[0164] Table 6

[0165]

[0166] In this embodiment, the field curvature curve, F-Tan(Theta) distortion curve, axial aberration curve, and lateral chromatic aberration curve of the optical lens 600 are respectively as Figure 27 , Figure 28 , Figure 29 , Figure 30 shown.

[0167] It can be seen from Figure 27 that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 600 can well correct the field curvature.

[0168] It can be seen from Figure 28It can be seen that the F-Tan(Theta) distortion of the optical lens 600 is controlled within -3% to 0, indicating that the optical lens 600 can correct the distortion well.

[0169] From Figure 29 it can be seen that the offset of the axial aberration is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 600 can correct the axial aberration well.

[0170] From Figure 30 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1 μm to 1 μm, indicating that the optical lens 600 can correct the chromatic aberration excellently.

[0171] Example 7

[0172] Please refer to Figure 31 , which shows the schematic structural diagram of the optical lens 700 provided in Embodiment 7 of the present invention. Compared with Embodiment 1, the main differences are as follows: the image side surface S11 of the sixth lens L6 is a convex surface; the object side surface S12 of the seventh lens L7 is a concave surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0173] The relevant parameters of each lens in the optical lens 700 in Example 7 are shown in Table 7.

[0174] Table 7

[0175]

[0176] In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve graph, axial aberration curve graph, lateral chromatic aberration curve graph, and MTF curve graph of the optical lens 700 are respectively as Figure 32 , Figure 33 , Figure 34 , Figure 35 shown.

[0177] From Figure 32 it can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.02 mm to 0.04 mm, indicating that the optical lens 700 can correct the field curvature well.

[0178] From Figure 33 it can be seen that the F-Tan(Theta) distortion of the optical lens 700 is controlled within -3% to 0, indicating that the optical lens 700 can correct the distortion well.

[0179] From Figure 34 it can be seen that the offset of the axial aberration is controlled within -0.01 mm to 0.04 mm, indicating that the optical lens 700 can correct the axial aberration well.

[0180] From Figure 35 it can be seen that the vertical chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1μm to 1μm, indicating that the optical lens 700 can excellently correct chromatic aberration.

[0181] Please refer to Table 8 for the optical characteristics corresponding to the above-mentioned 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, and the values corresponding to each conditional formula in each embodiment.

[0182] Table 8

[0183]

[0184] In summary of the above embodiments, 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, enabling the lens to have one or more advantages such as long focal length, large aperture, and high imaging quality.

[0185] 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.

[0186] The above-mentioned embodiments only represent several implementation manners of the present invention. 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 sequentially includes from the object side to the imaging surface along the optical axis: A first lens with negative optical power, whose object side is concave and whose image side is convex; A second lens with positive optical power, whose object side and image side are both convex; A third lens with positive optical power, whose object side and image side are both convex; A fourth lens with negative optical power, whose object side and image side are both concave; A fifth lens with positive optical power, whose object side is convex and whose image side is concave; A sixth lens with positive optical power, whose object side is convex; A seventh lens with negative optical power, whose image side is concave; Wherein, the curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens satisfy: -0.91 < (R9 - R10) / (R9 + R10) < -0.69; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 0.5 / ° < TTL / (IH / 2) / (FOV / 2) < 0.62 / °.

2. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2 < TTL / f < 2.9; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 4 < TTL / IH < 4.

9.

3. 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: 0.96 < (IH / 2) / (f×Tan(FOV / 2)) < 1.01; the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -3.3 < f7 / f < -0.

5.

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 and the effective focal length f of the optical lens satisfy: 0.51 < IH / f < 0.59; the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.23 < BFL / f < 0.

36.

5. 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: -5.2 < f1 / f < -3.5; the curvature radius R1 of the object side of the first lens and the effective focal length f of the optical lens satisfy: -1.15 < R1 / f < -0.95; the curvature radius R2 of the image side of the first lens and the effective focal length f of the optical lens satisfy: -2.15 < R2 / f < -1.

6.

6. 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; the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 1.3 < R3 / f < 1.7; the curvature radius R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: -50 < R4 / f < -3.

9.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.74 < f3 / f < 0.99; the curvature radius R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: 0.59 < R5 / f < 0.71; the curvature radius R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: -2.3 < R6 / f < -1.

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: 1.05 < f5 / f < 2.15; the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.5 < R9 / f < 1.15; the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 5.4 < R10 / f < 21.

9. The optical lens according to claim 1, characterized in that: The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 4 < f1234 / f567 < 22.

10. The optical lens according to claim 1, characterized in that: 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: -0.33 < (R1 - R2) / (R1 + R2) < -0.

2.

11. The optical lens according to claim 1, characterized in that: The clear aperture semi-diameter d9 of the object side surface of the fifth lens and the sagittal height Sag9 of the clear aperture of the object side surface of the fifth lens satisfy: 0.07 < Sag9 / d9 < 0.31; the clear aperture semi-diameter d10 of the image side surface of the fifth lens and the sagittal height Sag10 of the clear aperture of the image side surface of the fifth lens satisfy: 0 < Sag10 / d10 < 0.03.

Images