Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a front lens group with negative focal power and a rear lens group with positive focal power from an object side to an imaging surface along an optical axis, the front lens group comprises a first lens with negative focal power, and the image side surface of the first lens is a concave surface; the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; the rear lens group comprises a third lens with positive focal power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; the fourth lens has positive focal power; the fifth lens has positive focal power, and the image side surface of the fifth lens is a convex surface; the sixth lens has positive focal power, the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens near the optical axis is a convex surface; and the object side surface of the seventh lens is a concave surface near the optical axis, and the image side surface of the seventh lens is a convex surface. The optical lens provided by the invention has one or more advantages of ultra-wide angle, ultra-large aperture, large image plane, high pixel, high imaging quality and the like.

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 expectations for driving experience continue to rise, the use of automotive optical lenses in intelligent driving is increasing, and their status in the automotive industry is constantly improving. In the field of vehicle driving, conventional dashcam lenses cannot simultaneously combine the advantages of large aperture, wide angle, and high pixel count. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens having one or more advantages such as ultra-wide angle, ultra-large aperture, and high pixel.

[0004] The present invention provides an optical lens having seven lenses in total, which comprises, in order from the object side to the imaging surface along the optical axis: a front lens group with negative optical power, a rear lens group with positive optical power; The front lens group includes the following elements along the optical axis from the object side to the imaging surface: a first lens having negative optical power and a concave image-side surface; a second lens having positive refractive power, whose object-side surface is concave and whose image-side surface is convex; The rear lens group includes the following elements along the optical axis from the object side to the imaging plane: a third lens element having positive optical power, whose object-side surface is convex and whose image-side surface is convex; a fourth lens element having positive optical power; a fifth lens element having positive refractive power and a convex image-side surface; a sixth lens element having positive refractive power, whose object-side surface is concave and whose image-side surface is convex near the optical axis; a seventh lens element having optical power, wherein the object side surface thereof is concave near the optical axis and the image side surface thereof is convex; The maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy the following conditions: 130° <FOV / Fno<150°。

[0005] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.5 <TTL / f<7.8。

[0006] Further preferably, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens meet the following requirements: 2.6 <TTL / IH<3。

[0007] Further preferably, the maximum clear aperture DM1 of the first lens, the true image height IH corresponding to the maximum field angle of the optical lens, and the maximum field angle FOV of the optical lens satisfy: 0.42 < DM1 / IH / tan(FOV / 2) < 0.6.

[0008] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -3.5 < f1 / f < -2.

[0009] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 12 < f2 / f < 50; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: -1.5 < R3 / f < -0.7.

[0010] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.2 < f3 / f < 2.6; the curvature radius R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: -6 < R6 / f < -2.5.

[0011] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 20 < f4 / f < 220.

[0012] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 1.5.

[0013] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 10.5 < f6 / f < 18.5.

[0014] Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 10 < |f7 / f| < 55; the curvature radius R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: -1 < R14 / f < -0.75.

[0015] 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 aberration, improve the imaging quality of the optical lens, and enable the lens to have one or more advantages such as ultra-wide angle, large aperture, large image plane, high pixel, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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, where: Figure 1Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0017] Figure 2 Graph showing the field curvature of the optical lens in Example 1 of the present invention.

[0018] Figure 3 2 is an f-θ distortion curve of the optical lens in Example 1 of the present invention.

[0019] Figure 4 1 is an axial aberration curve diagram of the optical lens in Example 1 of the present invention.

[0020] Figure 5 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0021] Figure 6 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0022] Figure 7 Graph showing the field curvature of the optical lens in Example 2 of the present invention.

[0023] Figure 8 2 is an f-θ distortion curve of the optical lens in Example 2 of the present invention.

[0024] Figure 9 2 is an axial aberration curve diagram of the optical lens in Example 2 of the present invention.

[0025] Figure 10 Graph showing vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0026] Figure 11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0027] Figure 12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0028] Figure 13 2 is an f-θ distortion curve of the optical lens in Example 3 of the present invention.

[0029] Figure 14 4 is an axial aberration curve diagram of the optical lens in Example 3 of the present invention.

[0030] Figure 15 Graph showing vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0031] Figure 16 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0032] Figure 17 4 is a field curvature curve diagram of the optical lens in Example 4 of the present invention.

[0033] Figure 18 4 is an f-θ distortion curve of the optical lens in Example 4 of the present invention.

[0034] Figure 19 4 is an axial aberration curve diagram of the optical lens in Example 4 of the present invention.

[0035] Figure 20 Graph showing vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0036] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] The optical lens provided by the embodiment of the present invention comprises seven lenses in total, and includes, along the optical axis from the object side to the imaging plane, a front lens group with negative optical power and a rear lens group with positive optical power.

[0045] Specifically, the front lens group includes, in order from the object side to the image plane along the optical axis: a first lens and a second lens. The first lens may have negative optical power, its object-side surface may be concave or convex, and its image-side surface is concave; the second lens may have positive optical power, its object-side surface may be concave, and its image-side surface may be convex.

[0046] Specifically, the rear lens group includes, along the optical axis from the object side to the imaging plane, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Among them, the third lens may have positive optical power, its object side surface is convex, and its image side surface is convex. The fourth lens may have positive optical power, its object side surface may be concave or convex, and its image side surface may be concave or convex. The fifth lens may have positive optical power, its object side surface may be concave or convex, and its image side surface is convex. The sixth lens may have positive optical power, its object side surface is concave, and its image side surface is convex at the near optical axis. The seventh lens may have positive optical power or negative optical power, its object side surface is concave at the near optical axis, and its image side surface is convex.

[0047] In some embodiments, the optical lens may further include an aperture which may be located between the second lens and the third lens, i.e., between the front lens group and the rear lens group. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image. When the aperture is located between the second lens and the third lens, it is convenient for correcting the aperture aberration.

[0048] 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 and preventing the photosensitive chip from being damaged and affecting the imaging effect of the lens.

[0049] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 130° < FOV / Fno < 150°. Meeting the above conditions is beneficial to expanding the field of view angle of the optical lens and increasing the aperture of the optical lens, realizing the characteristics of ultra-wide angle and large aperture of the lens. The realization of the ultra-wide angle characteristic is beneficial for the optical lens to obtain more scene information and meet the requirements of large-range detection. The realization of the large aperture characteristic is beneficial to improving the problem that the relative brightness of the edge field of view decreases rapidly due to the wide angle, and thus is also beneficial to obtaining more scene information.

[0050] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.5 < TTL / f < 7.8. Meeting the above conditions can effectively limit the length of the lens and is beneficial to the miniaturization of the optical lens.

[0051] 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: 2.6 < TTL / IH < 3. Meeting the above conditions can better realize the miniaturization of the lens. At the same time, when ensuring the same total length of the lens, it has a larger image plane and can match a larger-size imaging chip to achieve high-definition imaging.

[0052] In some embodiments, the maximum clear aperture DM1 of the first 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: 0.42 < DM1 / IH / tan(FOV / 2) < 0.6. Meeting the above conditions ensures that the lens has a larger light-receiving surface, realizes the ultra-wide angle imaging of the lens, and is also beneficial to reducing the rear aperture of the lens to realize the miniaturization of the optical lens.

[0053] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -3.5 < f1 / f < -2. Meeting the above conditions, the first lens adopts a suitable negative refractive power, which can slow down the incident angle of light at the second lens while ensuring an increased field of view angle, effectively reducing the aperture of the subsequent lenses and maintaining the miniaturization of the lens.

[0054] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 12 < f2 / f < 50; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: -1.5 < R3 / f < -0.7. Meeting the above conditions, by setting the second lens to have a suitable positive refractive power and a meniscus shape, it is possible to effectively converge a large range of light entering the system, and at the same time correct the off-axis aberration brought by the first lens, improving the imaging quality of the optical lens.

[0055] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.2 < f3 / f < 2.6; the curvature radius R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: -6 < R6 / f < -2.5. Meeting the above conditions, it is possible to effectively reduce the difficulty of correcting the marginal field distortion, ensure that the lens has a small distortion while achieving a large field of view angle, improve the overall imaging quality, and at the same time reduce the system sensitivity and improve the manufacturing yield.

[0056] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 20 < f4 / f < 220. Meeting the above conditions is beneficial to the smooth transition of the light trend, improving the imaging quality of the optical lens, and at the same time reducing the system sensitivity and improving the manufacturing yield.

[0057] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 1.5. Meeting the above conditions is beneficial to balancing the astigmatism and field curvature of the optical lens and improving the imaging quality of the optical lens.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 10.5 < f6 / f < 18.5. Meeting the above conditions is beneficial to balancing the astigmatism and field curvature of the optical lens and improving the imaging quality of the optical lens.

[0059] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 10 < |f7 / f| < 55; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: -1 < R14 / f < -0.75. Meeting the above conditions is beneficial to diverge the incident light to a certain extent, causing the peripheral light and the central light to turn upward, reaching a higher imaging position, better achieving large-format imaging of the lens, and improving the imaging quality.

[0060] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.6 < BFL / f < 0.8. Meeting the above conditions can make the lens have a large optical back focal length, which is beneficial to reducing the interference between the lens and the imaging chip, ensuring the compatibility between the lens and the body, and making the structure of the lens more compact.

[0061] 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: 53° < (f × FOV) / IH < 65°. Meeting the above conditions is beneficial to achieving the balance between the large field angle and large-format imaging of the optical lens by reasonably restricting the relationship between the focal length, field angle, and image height of the optical lens.

[0062] 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: 2.2 < IH / EPD < 3. Meeting the above conditions can effectively increase the width of the incident light beam at different field angles, improve the brightness of the optical lens at the image plane to avoid the generation of vignetting, and at the same time increase the imaging area of the optical lens to achieve large-format imaging of the lens.

[0063] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: 0.03 < f5 / f6 < 0.1. Meeting the above conditions is beneficial to the smooth transition of light, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens.

[0064] In some embodiments, the object-side curvature radius R3 of the second lens and the image-side curvature radius R4 of the second lens satisfy: 0.7 < R3 / R4 < 1. Meeting the above conditions, by setting the second lens to a meniscus shape close to a concentric circle, the deflection angle of light in the second lens can be alleviated, and at the same time, the chromatic aberration and distortion generated by the first lens can be effectively balanced, improving the overall imaging quality.

[0065] In some embodiments, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: -1.5 < R5 / R6 < -0.2. Meeting the above conditions, by setting the biconvex surface type of the third lens, it is beneficial to better achieve the convergence of light, shorten the distance of light reaching the next lens, and is beneficial to reducing the total length of the optical lens.

[0066] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: 0.7 < R11 / R12 < 0.95. Meeting the above conditions is beneficial to better achieve the convergence of light, shorten the distance of light reaching the next lens, and is beneficial to reducing the total length of the optical lens.

[0067] In some embodiments, the radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: 0.5 < R13 / R14 < 0.8. Meeting the above conditions, by reasonably controlling the radius of curvature of the object side surface and the image side surface of the seventh lens, the incident angle of light on the image plane can be reduced, the illuminance of the edge field of view can be enhanced, and at the same time, it is beneficial to match the lens with an imaging chip with a smaller chief ray angle (CRA).

[0068] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the total optical length TTL of the optical lens satisfy: 0.55 < ∑CT / TTL < 0.66. Meeting the above conditions can effectively compress the total length of the optical lens, and at the same time is beneficial to the structural design and production process of the optical lens.

[0069] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f37 of the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: -3 < f12 / f37 < -1.2. Meeting the above conditions, by reasonably setting the focal length relationship between the lens groups before and after the aperture stop, it helps to achieve a smooth transition of light, expand the field angle of the optical imaging lens, reduce the difficulty of correcting distortion and chromatic aberration of the rear lens group, and improve the image quality of the optical lens.

[0070] In some embodiments, the optical lens satisfies the conditional formula: 24.5 mm < TTL < 26.5 mm, 3 mm < f < 4 mm, 140° < FOV < 150°, 8.6 mm < IH < 9.2 mm, 0.9 < Fno < 1.1, where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, IH represents the true image height corresponding to the maximum field angle of the optical lens, and Fno represents the aperture value of the optical lens. Meeting the above conditions indicates that the lens has a large field angle and can achieve a large shooting range; it has a large aperture value and can achieve high-definition imaging even in a relatively dark environment.

[0071] In some embodiments, the seven lenses in the optical lens can all be plastic lenses or a glass-plastic hybrid structure. Preferably, the optical lens of the present invention utilizes a seven-lens glass-plastic hybrid structure to improve thermal stability. Specifically, the first and third lenses can be glass lenses, while the second, fourth, fifth, sixth, and seventh lenses can all be plastic lenses. The glass-plastic hybrid structure effectively reduces costs, corrects aberrations, and reduces size, providing a more cost-effective optical lens product.

[0072] In some embodiments, the first, second, third, fourth, fifth, sixth, and seventh lenses may be spherical or aspherical lenses. Compared to spherical lenses, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number and size of lenses and achieving better miniaturization. More specifically, in the optical lens provided by the present invention, the first and third lenses may be spherical lenses, while the second, fourth, fifth, sixth, and seventh lenses may be aspherical lenses.

[0073] 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: ; 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, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients, respectively.

[0074] 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.

[0075] Example 1 See also Figure 1 , shown is a schematic structural diagram of the optical lens 100 provided in Example 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging surface S19, a front lens group with negative optical power, an aperture ST, a rear lens group with positive optical power, a filter G1, and a protective glass G2.

[0076] The front lens group includes, in order from the object side to the imaging surface along the optical axis: a first lens L1 and a second lens L2.

[0077] The first lens L1 has negative refractive power, its object-side surface S1 is concave, and its image-side surface S2 is concave; The second lens L2 has positive refractive power, its object-side surface S3 is concave, and its image-side surface S4 is convex.

[0078] The rear lens group includes, in order from the object side to the imaging plane along the optical axis: a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

[0079] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is convex. The fourth lens L4 has positive refractive power, its object-side surface S7 is concave, and its image-side surface S8 is convex; The fifth lens L5 has positive refractive power, its object-side surface S9 is convex, and its image-side surface S10 is convex; The sixth lens L6 has positive refractive power, its object-side surface S11 is concave, and its image-side surface S12 is convex near the optical axis; The seventh lens L7 has positive refractive power, its object-side surface S13 is concave near the optical axis, and its image-side surface S14 is convex; The object-side surface S15 and the image-side surface S16 of the filter G1 are both flat surfaces; The object side surface S17 and the image side surface S18 of the protective glass G2 are both flat surfaces; The imaging surface S19 is a plane.

[0080] The first lens L1 and the third lens L3 are glass spherical lenses; the second lens L2, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are plastic aspherical lenses.

[0081] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0082] Table 1-1 The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0083] Table 1-2 In this embodiment, the field curvature curve, f-θ distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are shown as follows: Figure 2 、 Figure 3 、 Figure 4 、 Figure 5shown.

[0084] Figure 2 A field curvature graph of the optical lens 100 in this embodiment is shown, showing 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 field angle (unit: degrees). As can be seen from the graph, the field curvature in the meridional and sagittal image planes is controlled within ±0.15mm, indicating that the optical lens 100 can effectively correct for field curvature.

[0085] Figure 3 The f-θ distortion curve of the optical lens 100 in this embodiment is shown. It shows the distortion at different field angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the field angle (unit: °). As can be seen from the figure, the distortion value is controlled within ±10%, indicating that the optical lens 100 is able to correct distortion well.

[0086] Figure 4 The following is a graph showing the axial aberration of the optical lens 100 in this embodiment, which shows 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 ±0.08 mm, indicating that the optical lens 100 is able to effectively correct the axial aberration.

[0087] Figure 5 A graph showing the vertical chromatic aberration of 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. As can be seen from the graph, the vertical chromatic aberration for the longest and shortest wavelengths is controlled within ±7 μm, indicating that the optical lens 100 is capable of effectively correcting chromatic aberration.

[0088] Example 2 See also Figure 6 , shown is a schematic structural diagram of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S7 of the fourth lens L4 is convex; the image-side surface S8 of the fourth lens L4 is concave; the object-side surface S9 of the fifth lens L5 is concave at the near optical axis; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0089] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0090] Table 2-1 The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0091] Table 2-2 In this embodiment, the field curvature curve, f-θ distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 200 are shown as follows: Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 shown.

[0092] from Figure 7 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 200 can correct the field curvature well.

[0093] from Figure 8 It can be seen from the figure that the distortion value is controlled within ±8%, indicating that the optical lens 200 can correct the distortion well.

[0094] from Figure 9 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.1 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0095] from Figure 10 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±7μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0096] Example 3 See also Figure 11 , shown is a schematic structural diagram of an optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is convex; the object-side surface S9 of the fifth lens L5 is concave; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0097] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0098] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0099] Table 3-2 In this embodiment, the field curvature curve, f-θ distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown as follows: Figure 12、 Figure 13 、 Figure 14 、 Figure 15 shown.

[0100] from Figure 12 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.15 mm, indicating that the optical lens 300 can correct the field curvature well.

[0101] from Figure 13 It can be seen that the distortion value is controlled within ±10%, indicating that the optical lens 300 can correct the distortion well.

[0102] from Figure 14 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.1 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0103] from Figure 15 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±6μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0104] Example 4 See also Figure 16 , shown is a schematic structural diagram of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, this embodiment has the following main differences: the seventh lens L7 has negative optical power; the object-side surface S1 of the first lens L1 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0105] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0106] Table 4-1 The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0107] Table 4-2 In this embodiment, the field curvature curve, f-θ distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 400 are shown as follows: Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 shown.

[0108] from Figure 17 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 400 can correct the field curvature well.

[0109] from Figure 18 It can be seen that the distortion value is controlled within ±10%, indicating that the optical lens 400 can correct the distortion well.

[0110] from Figure 19 It can be seen that the offset of the axial aberration is controlled within ±0.08 mm, indicating that the optical lens 400 can correct the axial aberration well.

[0111] from Figure 20 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±8μm, indicating that the optical lens 400 can correct chromatic aberration well.

[0112] Please refer to Table 5, 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.

[0113] Table 5 In summary of the above embodiments, the optical lens provided by the present invention adopts a seven-piece glass-plastic hybrid structure. Through a specific surface shape setting and a reasonable optical focal length distribution, 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, ultra-large aperture, large image surface, high pixel, and high imaging quality.

[0114] 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.

[0115] 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, comprising seven lenses, characterized in that: It sequentially includes, from the object side to the imaging surface along the optical axis: a front lens group with a negative optical power and a rear lens group with a positive optical power; The front lens group sequentially includes, from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose image side is concave; A second lens with a positive optical power, whose object side is concave and whose image side is convex; The rear lens group sequentially includes, from the object side to the imaging surface along the optical axis: A third lens with a positive optical power, whose object side is convex and whose image side is convex; A fourth lens with a positive optical power; A fifth lens with a positive optical power, whose image side is convex; A sixth lens with a positive optical power, whose object side is concave and whose image side is convex near the optical axis; A seventh lens with an optical power, whose object side is concave near the optical axis and whose image side is convex; Wherein, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 130° < FOV / Fno < 150°.

2. The optical lens according to claim 1, wherein: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.5 < TTL / f < 7.

8.

3. The optical lens according to claim 1, wherein: 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: 2.6 < TTL / IH < 3.

4. The optical lens according to claim 1, wherein: The maximum clear aperture DM1 of the first lens, the true image height IH corresponding to the maximum field angle of the optical lens and the maximum field angle FOV of the optical lens satisfy: 0.42 < DM1 / IH / tan(FOV / 2) < 0.

6.

5. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -3.5 < f1 / f < -2.

6. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 12 < f2 / f < 50; the curvature radius R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: -1.5 < R3 / f < -0.

7.

7. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 2.2 < f3 / f < 2.6; the curvature radius R6 of the image side of the third lens and the effective focal length f of the optical lens satisfy: -6 < R6 / f < -2.

5.

8. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 20 < f4 / f < 220.

9. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 1.

5.

10. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 10.5 < f6 / f < 18.

5.

11. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 10 < |f7 / f| < 55; the curvature radius R14 of the image side of the seventh lens and the effective focal length f of the optical lens satisfy: -1 < R14 / f < -0.75.

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