Optical lens

Abstract

The invention provides an optical lens, which consists of 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 convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a concave surface; the fifth lens has positive focal power, and the object side surface of the fifth lens is a convex surface; the image side surface is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a convex surface; and the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a concave surface. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved.

Description

Technical Field

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

[0002] As people's requirements for driving experience continue to increase, the use of in-vehicle optical lenses in intelligent driving is increasing, and the status of in-vehicle optical lenses in the automotive-related industry is constantly improving. In the field of vehicle driving, in order to improve vehicle driving safety and driving intelligence, it is necessary to monitor the vehicle cabin, and OMS (passenger monitoring) vehicle lenses have developed rapidly. The existing in-vehicle cabin monitoring lenses generally have a resolution of about 1M or 2M, and as the lens FOV increases, the angular resolution and resolution drop sharply. In addition to requiring the optical lens to be thin and light, with a small front diameter and high pixels and high resolution, the OMS system lens also requires the optical lens to be able to form clear images under low illumination conditions. Therefore, it is necessary to develop an optical lens with good imaging effect. Summary of the Invention

[0003] In view of the above problems, an object of the present invention is to provide an optical lens having the advantage of excellent imaging quality.

[0004] The technical solution adopted in the present invention is:

[0005] An optical lens, consisting of seven lenses, including the following elements from the object side to the imaging surface along the optical axis:

[0006] The first lens has a negative optical power, its object-side surface is convex and its image-side surface is concave;

[0007] a second lens having negative optical power, the object-side surface of which is convex and the image-side surface of which is concave;

[0008] a third lens element having negative optical power, whose object-side surface and image-side surface are concave;

[0009] a fourth lens element having positive refractive power, whose object-side surface is convex and whose image-side surface is concave;

[0010] The fifth lens element has positive refractive power, its object-side surface is convex, and its image-side surface is convex;

[0011] a sixth lens element having negative optical power, whose object-side surface is concave and whose image-side surface is convex;

[0012] a seventh lens element having positive refractive power, whose object-side surface is convex and whose image-side surface is concave;

[0013] Among them, the curvature radius R13 of the object side of the seventh lens and the curvature radius R14 of the image side of the seventh lens satisfy: -0.5 < (R13 - R14) / (R13 + R14) < 0.

[0014] Further preferably, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.6 < TTL / f < 7; the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 2.2 < TTL / IH < 2.7.

[0015] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.2 < IH / EPD < 6.3; 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: -1.65 < f1234 / f567 < -1.1.

[0016] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.25 < IH / f < 3.1; the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.9.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -5.5 < f2 / f < -3.9; the effective focal length f of the optical lens and the curvature radius R3 of the object side of the second lens satisfy: 0.55 < R3 / f < 0.7%.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -2.75 < f3 / f < -2. ; the curvature radius R5 of the object side of the third lens and the effective focal length f of the optical lens satisfy: -1.9 < R5 / f < -1.4; the curvature radius R6 of the image side of the third lens and the effective focal length f of the optical lens satisfy: 5.7 < R6 / f < 7.4.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 1.8 < f4 / f < 2.2; the effective focal length f of the optical lens and the curvature radius R8 of the image side of the fourth lens satisfy: < R8 / f < 53.1.

[0020] It should be noted that there is an error in the original text where "0.55 < R3 / f < 0.7%" should probably be "0.55 < R3 / f < 0.75". The translation has been done based on the original text as provided.Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -0.9 < f6 / f < -0.7; the effective focal length f of the optical lens and the image-side curvature radius R12 of the sixth lens satisfy: -3.5 < R12 / f < -2.3.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.7 < f7 / f < 3.55; the effective focal length f of the optical lens and the image-side curvature radius R14 of the seventh lens satisfy: 1.4 < R14 / f < 2.6.

[0022] Further preferably, the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: -1 < (R11 - R12) / (R11 + R12) < -0.5; the object-side curvature radius R5 of the third lens and the image-side curvature radius R6 of the third lens satisfy: -0.8 < (R5 + R6) / (R5 - R6) < -0.3.

[0023] Compared with the prior art, the optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape combinations and reasonable optical power distributions, it can improve the imaging quality of the optical lens, reduce aberrations, improve the imaging quality of the optical lens, and endow the lens with one or more advantages such as ultra-wide angle, large aperture, miniaturization, and high pixel. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is an F-Theta distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6 is an MTF curve diagram of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 7 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0032] Figure 8 Graph showing the field curvature of the optical lens in Example 2 of the present invention.

[0033] Figure 9 Graph showing the F-Theta distortion of the optical lens in Example 2 of the present invention.

[0034] Figure 10 2 is an axial aberration curve diagram of the optical lens in Example 2 of the present invention.

[0035] Figure 11 Graph showing vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0036] Figure 12 This is an MTF curve diagram of the optical lens in Example 2 of the present invention.

[0037] Figure 13 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0038] Figure 14 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0039] Figure 15 Graph showing the F-Theta distortion of the optical lens in Example 3 of the present invention.

[0040] Figure 16 4 is an axial aberration curve diagram of the optical lens in Example 3 of the present invention.

[0041] Figure 17 Graph showing vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0042] Figure 18 This is the MTF curve of the optical lens in Example 3 of the present invention.

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

[0044] For a better understanding of 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 merely descriptions of embodiments of the present application and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of the present invention.

[0046] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0047] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0048] It should also be understood that the terms "comprises," "including," "having," "includes," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application." And, the term "exemplary" is intended to refer to an example or illustration.

[0049] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0050] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0051] The optical lens provided in an embodiment of the present invention is composed of seven lenses, which are, along the optical axis from the object side to the imaging surface, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens.

[0052] 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 negative focal power, with its object side being convex and its image side being concave. The third lens may have a negative focal power, with its object side being concave and its image side being concave. The fourth lens may have a positive focal power, with its object side being convex and its image side being concave. The fifth lens may have a positive focal power, with its object side being convex; its image side being convex. The sixth lens may have a negative focal power, with its object side being concave and its image side being convex. The seventh lens may have a positive focal power, with its object side being convex and its image side being concave.

[0053] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the fourth lens and the fifth lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the imaging. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the imaging. When the aperture is located between the fourth lens and the fifth lens, it is convenient for the correction of aperture aberration.

[0054] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the seventh lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging. <00OO132>In some embodiments, the fifth lens and the sixth 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.

[0056] In some embodiments, the radius of curvature R13 of the object side of the seventh lens and the radius of curvature R14 of the image side of the seventh lens satisfy: -0.5 < (R13 - R14) / (R13 + R14) < 0. Meeting the above range defines that the seventh lens has a suitable surface shape, enabling the light rays to smoothly transition to the rear, reducing the height of the light rays incident on the rear, slowing down the upward trend of the light rays, avoiding the light energy loss caused by the excessive main ray angle of the large field of view light rays when reaching the imaging surface, being conducive to improving the illuminance of the edge field of view, and being beneficial to achieving a short optical total length. More specifically, -0.34 < (R13 - R14) / (R l3 + R14) < -0.2.

[0057] In some embodiments, the optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.6 < TTL / f < 7. Meeting the above range can effectively limit the length of the lens and is conducive to the miniaturization of the optical lens. More specifically, 6.22 < TTL / f < 6.84.

[0058] In some embodiments, the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 2.2 < TTL / IH < 2.7. Meeting the above range ensures that, with the same total length of the lens, a larger image plane can be obtained, enabling it to match a larger-sized imaging chip to achieve high-definition imaging, and better achieving the balance between the small total length and the large image plane of the lens. More specifically, 2.44 < TTL / IH < 2.48.

[0059] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.2 < IH / EPD < 6.3. Meeting the above range can increase the width of the light beam entering the optical lens, improving the brightness at the image plane of the optical lens and avoiding vignetting. More specifically, 4.63 < IH / EPD < 5.71.

[0060] 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: -1.6 < f1234 / f567 < -1.1. Meeting the above range is conducive to balancing various aberrations of the system and improving the overall imaging quality by reasonably setting the relationship between the lens groups before and after the aperture. More specifically, -1.52 < f1234 / f567 < -1.24.

[0061] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.25 < IH / f < 3.1. Meeting the above range and controlling the image height and focal length of the optical lens within a reasonable range help the optical lens to have the characteristic of a large image plane and improve the imaging quality. More specifically, 2.51 < IH / f < 2.8.

[0062] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.9. Meeting the above range limits the optical lens to have an appropriate back focus, facilitating the reasonable arrangement of the positions of each lens and reducing the processing and assembly difficulty. More specifically, 0.56 < BFL / f < 0. < 8.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -5.5 < f2 / f < -3.9; the effective focal length f of the optical lens and the radius of curvature R3 of the object side surface of the second lens satisfy: 0.55 < R3 / f < 0.75. Meeting the above ranges controls the second lens to have an appropriate negative optical power and surface shape, which can share the negative optical power at the front end of the optical lens, thereby facilitating avoiding excessive light deflection caused by overly concentrated optical power of the first lens and reducing the difficulty of chromatic aberration correction of the optical lens. More specifically, -5.04 < f2 / f < -4.28; 0.64 < R3 / f < 0.69.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -2.75 < f3 / f < -2.1; the radius of curvature R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: -1.9 < R5 / f < -1.4; the radius of curvature R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: 5.7 < R6 / f < 7.4. Meeting the above ranges controls the third lens to have an appropriate negative optical power and surface shape, which has the effect of diverging light. At the same field angle, it further diverges the light rays emerging from the first lens and the second lens, can disperse the central light rays and edge light rays of each field, and enables the rear optical system to have a larger light receiving surface to receive the light rays emerging from the image side surface of the third lens, achieving a larger light input, which is beneficial to increasing the relative illumination. More specifically, -2.5 < f3 / f < -2.38; -1.74 < R5 / f < -1.6; 6.28 < R6 / f < 6.74.

[0065] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 1.8 < f4 / f < 2.2; the effective focal length f of the optical lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: 12.9 < R8 / f < 53.1. Meeting the above ranges can effectively converge the light rays, reduce the difficulty of correcting the distortion of the edge field, ensure that the lens has a small distortion while achieving a large field angle, and improve the overall imaging quality. More specifically, 1.99 < f4 / f < 2.05; 14.31 < R8 / f < 48.28.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -0.9 < f6 / f < -0.7; the effective focal length f of the optical lens and the image-side curvature radius R12 of the sixth lens satisfy: -3.5 < R12 / f < -2.3. Meeting the above ranges can effectively balance various aberrations generated by the front lens group, and at the same time is conducive to increasing the divergence degree of light, increasing the area of light entering the imaging surface, achieving large-format imaging of the lens, and improving the imaging quality of the optical lens. More specifically, -0.79 < f6 / f < -0.76; -3.16 < R12 / f < -2.53.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.7 < f7 / f < 3.55; the effective focal length f of the optical lens and the image-side curvature radius R14 of the seventh lens satisfy: 1.4 < R14 / f < 2.6. Meeting the above ranges can make the seventh lens have an appropriate positive optical power, which is conducive to balancing the astigmatism of the optical lens and improving the imaging quality of the optical lens. More specifically, 2.99 < f7 / f < 3.23; 1.54 < R14 / f < 2.35.

[0068] In some embodiments, the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: -1 < (R11 - R12) / (R11 + R12) < -0.5. Meeting the above ranges, controlling the surface shape of the sixth lens is conducive to increasing the imaging area and the field angle of the optical lens, conducive to balancing the aberrations of the optical lens, and improving the imaging quality of the optical lens. More specifically, -0.78 < (R11 - R12) / (R11 + R12) < -0.72.

[0069] In some embodiments, the object-side curvature radius R5 of the third lens and the image-side curvature radius R6 of the third lens satisfy: -0.8 < (R5 + R6) / (R5 - R6) < -0.3. Meeting the above ranges is conducive to the smooth transition of light, can effectively correct the distortion of the edge field of view, reduce the degree of deformation of the edge of the captured image, and improve the image quality. More specifically, -0.62 < (R5 + R6) / (R5 - R6) < -0.56.

[0070] In some embodiments, the maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 70° < FOV / Fno < 85°. Meeting the above ranges defines that the optical lens has an appropriate field angle and f-number, can collect light at a large angle and obtain good imaging quality. More specifically, 75.73° < FOV / Fno < 78.31°.

[0071] In some embodiments, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens, and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 50° < (f × FOV) / IH < 60°. Meeting the above range, by reasonably restricting the relationship between the focal length, field angle, and image height of the optical lens, it is possible to ensure that the optical lens has the characteristics of a large field of view and a large image plane, thereby enabling the optical lens to have good optical performance and being able to capture the details of the photographed object well. More specifically, 55.49° < (f × FOV) / IH < 57.52°.

[0072] In some embodiments, the overall 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: 0.5 < ∑CT / TTL < 0.6. Meeting the above range can effectively compress the overall length of the optical lens and is beneficial to the structural design and production process of the optical lens. More specifically, 0.52 < ∑CT / TTL < 0.55.

[0073] In some embodiments, the effective focal length f of the optical lens, the radian θ of the maximum half-field angle, and the true image height IH corresponding to the maximum field angle satisfy: 0.99 < (IH / 2) / (f × θ) < 1.04. Meeting the above range is beneficial to realizing the ultra-wide-angle characteristics of the optical lens and can control the optical lens to have a small distortion.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -3 < f1 / f < -2.4. Meeting the above range, by setting the first lens to have a negative refractive power, 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, increasing the light flux while achieving a large field of view. More specifically, -2.75 < f1 / f < -2.64.

[0075] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.7 < f5 / f < 0.9; the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: 0.9 < R9 / f < 1.15. Meeting the above conditions, setting the fifth lens to have a positive refractive power is beneficial to converging light while correcting the field curvature and distortion of the optical lens, improving the imaging quality of the optical lens. More specifically, 0.77 < f5 / f < 0.84; 0.99 < R9 / f < 1.04.

[0076] In some embodiments, the sagittal height Sag12 of the image-side clear aperture of the sixth lens and the image-side clear aperture d12 of the sixth lens satisfy: -0.3 < Sag12 / d12 < 0; the sagittal height Sag14 of the image-side clear aperture of the seventh lens and the image-side clear aperture d14 of the seventh lens satisfy: 0 < Sag14 / d14 < 0.3. Meeting the above ranges helps to control the trend of light rays in the peripheral field of view and highlight the detailed information of the central field of view of the optical lens. More specifically, -0.19 < Sag12 / d12 < -0.15; 0.1 < Sag14 / d14 < 0.19.

[0077] In some embodiments, the optical lens satisfies the conditional expressions: 2 mm < f < 2.5 mm, 1 mm < EPD < 1.35 mm, 12.6 mm < TTL < 16.5 mm, 1.65 < Fno < 2.25, 17.4° < CRA < 22°, 1.1 mm < BFL < 1.9 mm, 130° < FOV < 170°, 5.1 mm < IH < 6.7 mm; where f represents the effective focal length 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 f-number of the optical lens, CRA represents the principal ray angle of incidence at the maximum image height of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field angle of the optical lens, and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of miniaturization, large target surface, large field angle, large aperture, etc. More specifically, 2.19 mm < f < 2.26 mm, 1.08 mm < EPD < 1.23 mm, 14.03 mm < TTL < 15.01 mm, 1.84 < Fno < 2.06, 19.23° < CRA < 20.04°, 1.27 mm < BFL < 1.75 mm, 144° < FOV < 156°, 5.67 mm < IH < 6.14 mm.

[0078] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The first lens and the fourth lens in the optical lens provided by the present invention are made of glass lenses, and the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens are made of plastic lenses. The optical lens of the present invention adopts a glass-plastic hybrid structure to improve the thermal stability.

[0079] In some embodiments, the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, and seventh lens may be spherical lenses or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number and size of lenses, and better achieving lens miniaturization. More specifically, the first and fourth lenses of the present invention are spherical lenses, and the second, third, fifth, sixth, and seventh lenses may all be aspherical lenses. This can effectively reduce the aberrations of the optical lens, thereby reducing the number and size of lenses, and better achieving lens miniaturization.

[0080] In various embodiments of the present invention, when the lens is an aspheric lens, the shapes of the aspheric surfaces of the optical lens satisfy the following equations:

[0081]

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

[0083] The present invention is further illustrated below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens vary; for details, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the present invention is not limited thereto. Any other changes, substitutions, combinations, or simplifications that do not deviate from the novelties of the present invention shall be considered equivalent replacements and are included within the scope of protection of the present invention.

[0084] Example 1

[0085] See also Figure 1 , shown is a schematic structural diagram of the optical lens 100 provided in Example 1 of the present invention, which 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, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

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

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

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

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

[0090] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex, and its image-side surface S10 is convex;

[0091] The sixth lens L6 has negative refractive power, its object-side surface S10 is concave, and its image-side surface S11 is convex;

[0092] The fifth lens L5 and the sixth lens L6 form a cemented lens group with positive refractive power. That is, the cemented surface between the image-side surface of the fifth lens L5 and the object-side surface of the sixth lens L6 is S10.

[0093] The seventh lens L7 has positive refractive power, its object-side surface S12 is convex, and its image-side surface S13 is concave;

[0094] The object-side surface S14 and the image-side surface S15 of the filter G1 are both flat surfaces;

[0095] The imaging surface S16 is a plane.

[0096] The first lens L1 and the fourth lens L4 are glass spherical lenses, and the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are plastic aspherical lenses.

[0097] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0098] Table 1-1

[0099]

[0100] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0101] Table 1-2

[0102] Face number K B C D E F S3 -1.74E+00 1.92E-02 -1.09E-02 8.82E-04 3.03E-05 -6.62E-06 S4 -1.33E+00 2.55E-02 -1.60E-02 1.05E-03 2.75E-04 -2.41E-05 S5 -1.19E+01 -3.59E-02 2.16E-02 -5.76E-03 9.61E-04 -5.08E-05 S6 4.15E+01 -2.16E-02 1.32E-02 -3.52E-03 6.18E-04 -4.55E-05 S9 7.28E-01 -3.65E-02 7.41E-03 -8.61E-03 3.83E-03 -9.49E-04 S10 -2.51E+00 -2.95E-01 1.46E-01 -5.56E-02 1.58E-02 -1.76E-03 S11 -1.98E+01 -4.71E-02 1.98E-02 -4.18E-03 5.88E-04 -3.68E-05 S12 -5.18E+00 1.26E-03 -1.02E-03 9.87E-05 2.06E-05 -3.74E-06 S13 -7.96E+00 1.03E-02 -5.61E-03 1.10E-03 -9.73E-05 2.45E-06

[0103] Figure 2 The following figure shows the field curvature curve of the optical lens 100 in this embodiment, which shows the degree of curvature of light in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: degrees). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.04mm, indicating that the optical lens 100 can effectively correct the field curvature.

[0104] Figure 3The following figure shows the F-Theta distortion curve of the optical lens 100 in this embodiment, which represents the distortion at different field angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the distortion value is controlled within ±1%, indicating that the optical lens 100 is able to correct distortion well.

[0105] Figure 4 The following is a graph showing the axial aberration of the optical lens 100 in this embodiment, which represents the aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the graph, the offset of the axial aberration is controlled within ±0.05 mm, indicating that the optical lens 100 is able to effectively correct the axial aberration.

[0106] Figure 5 A graph of vertical chromatic aberration for the optical lens 100 in this embodiment shows 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 of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field of view angle. As can be seen from the graph, the vertical chromatic aberration for the longest and shortest wavelengths is controlled within ±4 μm, indicating that the optical lens 100 is capable of effectively correcting chromatic aberration.

[0107] Figure 6 A modulation transfer function (MTF) graph of the optical lens 100 in this embodiment is shown, representing the degree of lens imaging modulation at different spatial frequencies across various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the graph, the MTF value of this embodiment is consistently above 0.4 across the entire field of view. Within the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating excellent imaging quality and detail resolution at both low and high frequencies.

[0108] Example 2

[0109] See also Figure 7 , shown is a schematic structural diagram of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0110] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0111] Table 2-1

[0112]

[0113]

[0114] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0115] Table 2-2

[0116] Face number K B C D E F S3 -1.81E+00 1.99E-02 -1.08E-02 8.94E-04 3.29E-05 -7.33E-06 S4 -1.32E+00 2.51E-02 -1.61E-02 1.03E-03 2.86E-04 -3.22E-05 S5 -1.27E+01 -3.64E-02 2.15E-02 -5.77E-03 9.60E-04 -5.41E-05 S6 5.00E+01 -2.08E-02 1.32E-02 -3.57E-03 5.90E-04 -3.38E-05 S9 7.08E-01 -3.52E-02 6.94E-03 -8.72E-03 4.11E-03 -1.05E-03 S10 -2.57E+00 -2.87E-01 1.43E-01 -5.72E-02 1.61E-02 -1.53E-03 S11 -3.26E+01 -4.81E-02 1.97E-02 -4.19E-03 5.93E-04 -3.61E-05 S12 -5.92E+00 7.45E-04 -1.09E-03 9.67E-05 2.01E-05 -3.58E-06 S13 -1.01E+01 1.07E-02 -5.75E-03 1.09E-03 -9.67E-05 2.84E-06

[0117] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, vertical chromatic aberration curve, and MTF curve of the optical lens 200 are shown in FIG. Figure 8 、 Figure 9 、 Figure 10 、 Figure 11 、 Figure 12 shown.

[0118] from Figure 8 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.07 mm, indicating that the optical lens 200 can correct the field curvature well.

[0119] from Figure 9 It can be seen from the figure that the distortion value is controlled within ±3%, indicating that the optical lens 200 can correct the distortion well.

[0120] from Figure 10 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0121] from Figure 11 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0122] from Figure 12 As can be seen, the MTF value of this embodiment is above 0.38 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0123] Example 3

[0124] See also Figure 13 , shown is a schematic structural diagram of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main difference between this embodiment is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0125] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0126] Table 3-1

[0127]

[0128] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0129] Table 3-2

[0130]

[0131]

[0132] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, vertical chromatic aberration curve, and MTF curve of the optical lens 300 are shown as follows: Figure 14 、 Figure 15 、 Figure 16 、 Figure 17 、 Figure 18 shown.

[0133] from Figure 14 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 300 can correct the field curvature well.

[0134] from Figure 15 It can be seen from the figure that the distortion value is controlled within ±4%, indicating that the optical lens 300 can correct the distortion well.

[0135] from Figure 16 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.04 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0136] from Figure 17 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4 μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0137] from Figure 18 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0138] Please refer to Table 4, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, real image height IH corresponding to the maximum field of view angle, chief ray incidence angle CRA at the maximum image height, maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0139] Table 4

[0140]

[0141]

[0142] In summary, the optical lens provided by the present invention uses seven lenses with specific optical powers. Through the combination of specific surface shapes and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as ultra-wide angle, large aperture, miniaturization, and high pixel density.

[0143] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0144] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An optical lens, consisting of seven lenses, characterized in that: It successively includes from the object side to the imaging plane along the optical axis: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a negative optical power, whose object side is convex and whose image side is concave; A third lens with a negative optical power, whose object side is concave and whose image side is concave; A fourth lens with a positive optical power, whose object side is convex and whose image side is concave; A fifth lens with a positive optical power, whose object side is convex; whose image side is convex; A sixth lens with a negative optical power, whose object side is concave and whose image side is convex; A seventh lens with a positive optical power, whose object side is convex and whose image side is concave; Wherein, the curvature radius R13 of the object side of the seventh lens and the curvature radius R14 of the image side of the seventh lens satisfy: -0.5 < (R13 - R14) / (R13 + R14) < 0.

2. The optical lens according to claim 1, characterized in that: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.6 < TTL / f < 7; The overall 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: 2.2 < TTL / IH < 2.

7.

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 and the entrance pupil diameter EPD of the optical lens satisfy: 4.2 < IH / EPD < 6.3; 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: -1.65 < f1234 / f567 < -1.

1.

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: 2.25 < IH / f < 3.1; The back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.

9.

5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -5.5 < f2 / f < -3.9; The effective focal length f of the optical lens and the curvature radius R3 of the object side of the second lens satisfy: 0.55 < R3 / f < 0.

75.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -2.75 < f3 / f < -2.1; The curvature radius R5 of the object side of the third lens and the effective focal length f of the optical lens satisfy: -1.9 < R5 / f < -1.4; The curvature radius R6 of the image side of the third lens and the effective focal length f of the optical lens satisfy: 5.7 < R6 / f < 7.

4.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 1.8 < f4 / f < 2.2; The effective focal length f of the optical lens and the curvature radius R8 of the image side of the fourth lens satisfy: 12.9 < R8 / f < 53.

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 f6 of the sixth lens satisfy: -0.9 < f6 / f < -0.7; The effective focal length f of the optical lens and the image-side curvature radius R12 of the sixth lens satisfy: -3.5 < R12 / f < -2.

3.

9. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 2.7 < f7 / f < 3.55; The effective focal length f of the optical lens and the image-side curvature radius R14 of the seventh lens satisfy: 1.4 < R14 / f < 2.

6.

10. The optical lens according to claim 1, characterized in that: The object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: -1 < (R11 - R12) / (R11 + R12) < -0.5; The object-side curvature radius R5 of the third lens and the image-side curvature radius R6 of the third lens satisfy: -0.8 < (R5 + R6) / (R5 - R6) < -0.3.

Images