Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the second lens has negative focal power, the object side surface of the second lens is a concave surface near the optical axis, and the image side surface of the second lens is a concave surface; the object side surface and the image side surface of the third lens are concave surfaces; the object side surface and the image side surface of the fourth lens are convex surfaces; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface; the sixth lens has positive focal power, and the object side surface and the image side surface of the sixth lens are convex surfaces; the seventh lens has negative focal power, and the image side surface of the seventh lens is a concave surface near the optical axis; the curvature radius R3 of the object side surface of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy 0.1 lt; (R3 + R4) / (R3-R4) lt; and 0.8. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, the aberration is reduced, and the imaging quality of the optical lens is 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 the market environment continues to increase its requirements for panoramic camera lenses, panoramic lenses have been widely used, and the pursuit of the imaging effects of panoramic lenses has become more diversified, requiring both high-definition image quality and a wider viewing angle to record more information. These have made wide-angle high-definition imaging lenses receive more attention.

[0003] Since wide-angle lenses generally have large distortion, the edge imaging effect will be poor, and since the effective focal length of wide-angle lenses is short, the peripheral light entering will have a large compression deformation. Of course, wide-angle lenses have their unique perspective and sense of envelopment, but they appear to be seriously distorted for flat backgrounds. Therefore, how to overcome the distortion of wide-angle lenses is a difficult problem. The development of chips is also moving in two different directions: one is a large-target chip, which has good light transmittance and is very suitable for high-quality image processing needs. Under the same light conditions, it obtains more light information, better image quality, and more information for post-processing. But at the same time, the disadvantage is that the product volume and weight are large; the second is the miniaturization of the chip, which has a lower cost but poor imaging clarity. How to make the wide-angle lens have the advantages of large wide angle and small distortion, and match the imaging chip with a larger target surface to achieve high-definition imaging is a technical problem that technicians in this field need to solve. Summary of the invention

[0004] 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.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] An optical lens, comprising seven lenses, which include:

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

[0008] The second lens has a negative optical power, the object side surface of which is concave at the near optical axis, and the image side surface of which is concave;

[0009] The third lens has negative optical power, and both the object side surface and the image side surface are concave;

[0010] The fourth lens has positive refractive power, and both the object side surface and the image side surface are convex;

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

[0012] The sixth lens with positive optical power, both its object side and image side are convex surfaces;

[0013] The seventh lens with negative optical power, its image side is concave near the optical axis;

[0014] Wherein, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.1 < (R3 + R4) / (R3 - R4) < 0.8.

[0015] Further preferably, 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: 2.7 < TTL / IH < 3.4.

[0016] Further preferably, the maximum field of view angle FOV of the optical lens, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 55° < (FOV × f) / IH < 70°.

[0017] Further preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -18 < f3 / f < -4.5.

[0018] Further preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -6.2 < f7 / f < -2.5.

[0019] Further preferably, the effective focal length f of the optical lens and the combined focal length f123 of the first lens, the second lens and the third lens satisfy: -1.6 < f123 / f < -0.8; the effective focal length f of the optical lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfy: 1.5 < f4567 / f < 2.3.

[0020] Further preferably, the effective focal length f of the optical lens and the radius of curvature R3 of the object side of the second lens satisfy: -9.6 < R3 / f < -4.1; the effective focal length f of the optical lens and the radius of curvature R4 of the image side of the second lens satisfy: 2.4 < R4 / f < 3.2.

[0021] Further preferably, the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -6 < R5 / R6 < -0.8.

[0022] Further preferably, the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 0 < (R9 - R10) / (R9 + R10) < 0.5.

[0023] Further preferably, the sagittal height Sag3 of the light-passing semi-aperture on the object side of the second lens and the light-passing semi-aperture d3 of the object side of the second lens satisfy: 0 < Sag3 / d3 < 0.3; the sagittal height Sag4 of the light-passing semi-aperture on the image side of the second lens and the light-passing semi-aperture d4 of the image side of the second lens satisfy: 0.3 < Sag4 / d4 < 0.6.

[0024] The optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and endow the lens with one or more advantages such as an ultra-large field of view angle, small volume, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0026] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 2 is a field curvature curve graph of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 is an F-Theta distortion curve graph of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 is an axial aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 is a lateral chromatic aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 6 is an MTF curve graph of the optical lens in Embodiment 1 of the present invention.

[0032] Figure 7 is a relative illumination curve graph of the optical lens in Embodiment 1 of the present invention.

[0033] Figure 8 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0034] Fig. 9 is a field curvature curve graph of the optical lens in Embodiment 2 of the present invention.

[0035] Fig.10 is an F-Theta distortion curve graph of the optical lens in Embodiment 2 of the present invention.

[0036] Fig.11Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

[0037] Fig.12 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0038] Fig.13 This is an MTF curve diagram of the optical lens in Example 2 of the present invention.

[0039] Fig.14 This is a relative illumination curve diagram of the optical lens in Example 2 of the present invention.

[0040] Fig.15 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0041] Fig.16 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0042] Fig.17 : is the F-Theta distortion curve of the optical lens in Example 3 of the present invention.

[0043] Fig.18 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0044] Fig.19 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0045] Fig. 20 This is the MTF curve diagram of the optical lens in Example 3 of the present invention.

[0046] Fig.21 This is a relative illumination curve diagram of the optical lens in Example 3 of the present invention.

[0047] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0048] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application, and 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.

[0049] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0050] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0051] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0052] 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 exclude 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 listed 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.

[0053] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0054] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present 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.

[0055] The optical lens of the embodiment of the present invention comprises seven lenses in total, which are: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in order from the object side to the imaging surface along the optical axis.

[0056] In some embodiments, the first lens may have a negative optical power, with its object side being convex and its image side being concave. The second lens may have a negative optical power, with its object side being concave near the optical axis and its image side being concave. The third lens may have a negative optical power, with both its object side and image side being concave. The fourth lens may have a positive optical power, with both its object side and image side being convex. The fifth lens may have a negative optical power, with its object side being convex and its image side being concave. The sixth lens may have a positive optical power, with both its object side and image side being convex. The seventh lens may have a negative optical power, with its object side being either concave or convex and its image side being concave near the optical axis.

[0057] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the third lens and the fourth lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the imaging. When the diaphragm is located between the third lens and the fourth lens, it is convenient for the correction of diaphragm aberration.

[0058] 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.

[0059] In some embodiments, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.1 < (R3 + R4) / (R3 - R4) < 0.8. Satisfying the above range is beneficial to the smooth trend of light rays and reduces the aberration correction pressure of the rear lenses of the optical lens. More specifically, 0.25 < (R3 + R4) / (R3 - R4) < 0.52.

[0060] 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: 2.7 < TTL / IH < 3.4. Satisfying the above range is beneficial to achieving the balance between the volume of the optical lens and the image plane. More specifically, 2.94 < TTL / IH < 3.24.

[0061] In some embodiments, the maximum field of view angle FOV of the optical lens, the effective focal length f of the optical lens, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 55° < (FOV × f) / IH < 70°. Satisfying the above range limits the field of view angle, focal length, and image height of the optical lens within a reasonable range, which helps to balance the large field of view angle and the image plane and improve the overall structural stability of the lens. More specifically, 59.17° < (FOV × f) / IH < 65.72°.

[0062] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -18 < f3 / f < -4.5. Meeting the above range and defining that the third lens has an appropriate negative optical power helps share the negative refractive power of the front lens, reduce the generation of higher-order aberrations, and facilitate the subsequent lenses to improve the imaging quality. More specifically, -16.39 < f3 / f < -5.04.

[0063] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -6.2 < f7 / f < -2.5. Meeting the above range enables the seventh lens to have a negative optical power, which is beneficial to increasing the imaging area and field of view angle of the optical lens and improving the imaging quality of the optical lens. More specifically, -5.68 < f7 / f < -2.73.

[0064] In some embodiments, the effective focal length f of the optical lens and the combined focal length f123 of the first, second, and third lenses satisfy: -1.6 < f123 / f < -0.8; the effective focal length f of the optical lens and the combined focal length f4567 of the fourth, fifth, sixth, and seventh lenses satisfy: 1.5 < f4567 / f < 2.3. Meeting the above range, by reasonably setting the focal lengths of the lens groups before and after the aperture, it is beneficial to reduce the spherical aberration and field curvature generated by the front lens group of the optical lens, and at the same time enable the rear lens group to better balance the distortion and astigmatism generated by the front lens group, improving the imaging quality of the optical lens. More specifically, -1.46 < f123 / f < -0.92; 1.64 < f4567 / f < 2.08.

[0065] In some embodiments, the effective focal length f of the optical lens and the curvature radius R3 of the object side surface of the second lens satisfy: -9.6 < R3 / f < -4.1; the effective focal length f of the optical lens and the curvature radius R4 of the image side surface of the second lens satisfy: 2.4 < R4 / f < 3.2. Meeting the above range, by reasonably setting the shape of the object side surface of the second lens, it is beneficial to converge light, balance the aberrations brought by the first lens, reduce the difficulty of distortion correction, make the image in the edge field of view of the lens undistorted, and improve the imaging quality of the optical system. More specifically, -8.89 < R3 / f < -4.57; 2.69 < R4 / f < 2.91.

[0066] In some embodiments, the curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy: -6 < R5 / R6 < -0.8. Meeting the above range and reasonably defining the shape of the third lens can control the third lens to have an appropriate surface shape, make the light path reasonable, and improve the imaging quality. More specifically, -5.55 < R5 / R6 < -0.93.

[0067] In some embodiments, the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: 0 < (R9 - R10) / (R9 + R10) < 0.5. Meeting the above range can reduce spherical aberration and at the same time improve the relative illumination of the edge field of view. More specifically, 0.09 < (R9 - R10) / (R9 + R10) < 0.34.

[0068] In some embodiments, the sagittal height Sag3 of the clear aperture of the object side surface of the second lens and the clear aperture diameter d3 of the object side surface of the second lens satisfy: 0 < Sag3 / d3 < 0.3; the sagittal height Sag4 of the clear aperture of the image side surface of the second lens and the clear aperture diameter d4 of the image side surface of the second lens satisfy: 0.3 < Sag4 / d4 < 0.6. Meeting the above range helps to control the trend of light rays in the edge field of view and highlight the detailed information of the central field of view of the optical lens. More specifically, 0 < Sag3 / d3 < 0.21; 0.39 < Sag4 / d4 < 0.46.

[0069] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.8 < IH / EPD < 6.1. Meeting the above range can increase the width of the light beam entering the optical lens, improve the brightness of the optical lens at the image plane, and avoid vignetting. More specifically, 5.47 < IH / EPD < 6.09.

[0070] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle satisfy: 2.7 < IH / f < 3.7. Meeting the above range can reasonably control the relationship between the image height and the focal length, which helps the optical lens to achieve high pixel characteristics. More specifically, 3.03 < IH / f < 3.39.

[0071] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL satisfy: 0.75 < BFL / f < 0.95. Meeting the above range can make the lens have an appropriate back focus, which is beneficial to the assembly of the module, reduce interference, and improve the production yield. More specifically, 0.83 < BFL / f < 0.89.

[0072] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -6 < f1 / f < -4.3. Meeting the above range can make the first lens have a negative optical power, which is beneficial to reducing the inclination angle of the incident light rays, and is beneficial to collecting as much light in the edge field of view as possible into the rear optical lenses to achieve large-angle light collection. More specifically, -5.47 < f1 / f < -4.72.

[0073] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -4.4 < f2 / f < -2.8. Meeting the above range and defining that the second lens has an appropriate negative optical power helps to share the negative refractive power of the front lens, reduce the generation of high-order aberrations, and facilitate the subsequent lenses to improve the imaging quality. More specifically, -4.02 < f2 / f < -3.1.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.5 < f4 / f < 3.6. Meeting the above range can effectively converge light, correct the aberrations generated by the front lens, and improve the overall imaging quality. More specifically, 2.82 < f4 / f < 3.3.

[0075] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -23 < f5 / f < -4.2. Meeting the above range can make the fifth lens have a negative optical power, which is beneficial to increasing the imaging area and field of view angle of the optical lens and improving the imaging quality of the optical lens. More specifically, -20.74 < f5 / f < -4.74.

[0076] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 1.6 < f6 / f < 2. Meeting the above range can make the sixth lens have a positive optical power, improve the light converging ability of the optical lens, balance the aberrations of the optical lens, and improve the imaging quality of the optical lens. More specifically, 1.78 < f6 / f < 1.87.

[0077] In some embodiments, the effective focal length f of the optical lens and the curvature radius R5 of the object side surface of the third lens satisfy: -24.8 < R5 / f < -18.7; the effective focal length f of the optical lens and the curvature radius R6 of the image side surface of the third lens satisfy: 3.5 < R6 / f < 24.3. Meeting the above range and reasonably controlling the surface shapes of the object side and image side of the third lens helps to balance the high-order aberrations of the front lens and at the same time reduce the difficulty of aberration correction of the rear lens. More specifically, -22.67 < R5 / f < -20.69; 3.91 < R6 / f < 22.13.

[0078] In some embodiments, the focal length f2 of the second lens and the curvature radius R3 of the object side surface of the second lens satisfy: 1.3 < R3 / f2 < 2.5; the focal length f2 of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy: -1 < R4 / f2 < -0.6. By satisfying the above conditions and reasonably setting the surface shape of the second lens, the incident light can be further diverged, which is beneficial to increasing the field of view angle of the system. While increasing the field of view angle, the difficulty of distortion correction for the edge field of view can be reduced, making the lens have less distortion and improving the overall imaging quality. More specifically, 1.46 < R3 / f2 < 2.23; -0.88 < R4 / f2 < -0.71.

[0079] In some embodiments, the curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy: |(R5 + R6) / (R5 - R6)| < 0.8. By satisfying the above range and reasonably defining the shapes of the object side surface and the image side surface of the third lens, the third lens can be controlled to have an appropriate surface shape, making the light path reasonable and improving the imaging quality. More specifically, -0.04 < (R5 + R6) / (R5 - R6) < 0.7.

[0080] In some embodiments, the clear aperture d1 of the object side surface 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: -0.65 < d1 / IH / Tan(FOV / 2) < -0.45. By satisfying the above range, the relationship between the front port aperture, the field of view angle, and the image plane size of the optical lens can be balanced, which is beneficial to miniaturization. More specifically, -0.6 < d1 / IH / Tan(FOV / 2) < -0.49.

[0081] In some embodiments, the focal length f3 of the third lens and the distance CT34 along the optical axis between the third lens and the fourth lens satisfy: -38.7 < f3 / CT34 < -11.6. By satisfying the above range, the light deflection can be alleviated, the sensitivity of the system can be reduced, which is beneficial to reducing the astigmatism, distortion, and chromatic aberration of the optical imaging system and improving the resolution. More specifically, -35.17 < f3 / CT34 < -12.84.

[0082] In some embodiments, the optical lens satisfies the conditional expressions: 1.2 mm < f < 1.6 mm, 190° < FOV < 210°, 0.7 mm < EPD < 0.85 mm, 13 mm < TTL < 14 mm, 1.6 < Fno < 2, 4 mm < IH < 5 mm, 29° < CRA < 34°, 1.1 mm < BFL < 1.3 mm, where f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the f-number of the optical lens, IH represents the image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray angle of incidence at the maximum image height of the optical lens, and BFL represents the back focal length 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 a large field of view angle, a small volume, a relatively large image plane, and a large aperture. More specifically, 1.35 mm < f < 1.43 mm, 199° < FOV < 201°, 0.7 mm < EPD < 0.85 mm, 13.56 mm < TTL < 13.63 mm, 1.7 < Fno < 1.9, 4.1 mm < IH < 4.7 mm, 31.6° < CRA < 32°, 1.15 mm < BFL < 1.25 mm.

[0083] 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. In the optical lens provided by the present invention, the first lens and the fourth lens are made of glass lenses, and the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens are all made of plastic lenses. Adopting a glass-plastic hybrid structure can improve the thermal stability performance.

[0084] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens of the present invention adopt spherical lenses, and the first lens and the fourth lens adopt spherical lenses.

[0085] In various embodiments of the present invention, when the lens adopts an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0086]

[0087] Among them, z is the distance between the surface and the vertex of the surface 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, 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.

[0088] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0089] Example 1

[0090] See also Figure 1 , which is a schematic diagram of the structure of the optical lens 100 provided in Embodiment 1 of the present invention, and 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, an aperture ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0091] The first lens L1 has negative refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0092] The second lens L2 has negative refractive power, its object side surface S3 is concave at the near optical axis, and its image side surface S4 is concave;

[0093] The third lens L3 has negative refractive power, and its object-side surface S5 and image-side surface S6 are both concave;

[0094] The fourth lens L4 has positive refractive power, and its object-side surface S7 and image-side surface S8 are both convex surfaces;

[0095] The fifth lens L5 has negative refractive power, and its object-side surface S9 is convex, and its image-side surface S10 is concave;

[0096] The sixth lens L6 has positive refractive power, and its object-side surface S11 and image-side surface S12 are both convex surfaces;

[0097] The seventh lens L7 has negative refractive power, and its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis;

[0098] The object side surface S15 and the image side surface S16 of the filter G1 are both planes;

[0099] The imaging surface S17 is a plane.

[0100] The second lens, the third lens, the fifth lens, the sixth lens and the seventh lens are plastic aspherical lenses, and the first lens and the fourth lens are glass spherical lenses.

[0101] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0102] Table 1-1

[0103]

[0104]

[0105] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0106] Table 1-2

[0107] Face number K B C D E F G H S3 2.69E+00 2.14E-02 -1.99E-03 1.10E-04 4.23E-06 -4.42E-07 -4.22E-08 4.37E-09 S4 1.21E+00 1.62E-02 6.80E-04 1.75E-03 -8.46E-04 7.18E-05 6.05E-05 -1.27E-05 S5 8.10E+01 -2.44E-02 1.35E-03 -6.50E-04 8.15E-05 -5.22E-06 1.04E-05 -1.34E-06 S6 3.11E+00 -6.09E-03 3.31E-03 -1.32E-03 8.87E-04 -2.91E-04 5.49E-05 -2.67E-06 S9 -4.46E+00 -5.83E-02 1.41E-02 -5.37E-03 1.21E-03 2.59E-05 -2.71E-04 6.70E-05 S10 -2.37E+00 -4.36E-02 2.07E-02 -6.02E-03 1.07E-03 -2.03E-04 -4.01E-05 7.85E-06 S11 -4.05E-01 -1.35E-02 3.74E-03 -2.39E-04 -3.70E-04 9.25E-06 2.77E-05 4.97E-06 S12 -5.00E-02 1.37E-02 -7.39E-03 3.18E-03 -1.07E-03 3.59E-05 6.89E-05 1.72E-05 S13 1.51E+02 -6.77E-02 9.81E-03 -2.92E-03 -4.52E-04 1.90E-04 4.40E-05 -3.83E-06 S14 -1.05E+01 -3.80E-02 9.70E-03 -1.76E-03 -9.66E-05 6.52E-05 -1.91E-06 -9.69E-07

[0108] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, vertical chromatic aberration curve, MTF curve, and relative illumination curve of the optical lens 100 are shown in FIG. Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 shown.

[0109] Figure 2 The field curvature curve of Example 1 is shown, which indicates the degree of curvature of light of different wavelengths on the meridional image plane and the sagittal image plane, with the horizontal axis indicating the offset (unit: mm) and the vertical axis indicating the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.02 mm, indicating that the optical lens can correct the field curvature well.

[0110] Figure 3 The F-Theta distortion curve of Example 1 is shown, which represents the distortion of light of different wavelengths at different image heights on the imaging surface, with the horizontal axis representing the distortion value (unit: %) and the vertical axis representing the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within ±15%, indicating that the optical lens can correct the distortion well.

[0111] Figure 4 The axial aberration curve of the optical lens 100 in this embodiment is shown, 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. It can be seen from the figure that the offset of the axial aberration is controlled within ±0.02mm, indicating that the optical lens can better correct the axial aberration.

[0112] Figure 5 The vertical axis chromatic aberration curve of the optical lens 100 in this embodiment is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.55 μm) at different image heights on the imaging surface, the horizontal axis represents the vertical axis chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4 μm, indicating that the optical lens can correct chromatic aberration well.

[0113] Figure 6 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.3 in the whole field of view, and in the range of 0 to 200 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in both low-frequency and high-frequency conditions.

[0114] Figure 7 The relative illumination curve of Example 1 is shown, which represents the relative illumination values ​​at different viewing angles on the imaging surface, the horizontal axis represents the half viewing angle (unit: °), and the vertical axis represents the relative illumination (unit: %). It can be seen from the figure that the relative illumination value of the optical lens is still greater than 60% at the maximum half viewing angle, indicating that the optical lens has a good relative illumination.

[0115] Example 2

[0116] See also Figure 8 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. The optical lens of this embodiment is substantially the same as that of Example 1, and the main difference lies in that the optical parameters such as the curvature radius, aspheric coefficient, thickness, etc. of each lens surface are different.

[0117] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0118] Table 2-1

[0119]

[0120]

[0121] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0122] Table 2-2

[0123] Face number K B C D E F G H S3 2.69E+00 2.14E-02 -1.99E-03 1.10E-04 4.23E-06 -4.41E-07 -4.21E-08 4.38E-09 S4 1.21E+00 1.61E-02 5.91E-04 1.73E-03 -8.52E-04 7.09E-05 6.04E-05 -1.27E-05 S5 8.10E+01 -2.43E-02 1.37E-03 -6.49E-04 8.15E-05 -5.21E-06 1.04E-05 -1.32E-06 S6 3.11E+00 -6.09E-03 3.33E-03 -1.32E-03 8.85E-04 -2.93E-04 5.28E-05 -3.92E-06 S9 2.22E+116 -5.83E-02 1.40E-02 -5.39E-03 1.19E-03 1.94E-05 -2.74E-04 6.62E-05 S10 -2.37E+00 -4.36E-02 2.06E-02 -6.03E-03 1.06E-03 -2.06E-04 -4.30E-05 5.35E-06 S11 -4.05E-01 -1.33E-02 3.85E-03 -2.24E-04 -3.50E-04 9.90E-06 2.84E-05 5.48E-06 S12 -5.00E-02 1.37E-02 -7.40E-03 3.18E-03 -1.07E-03 3.97E-05 7.16E-05 1.89E-05 S13 1.51E+02 -6.77E-02 9.79E-03 -2.90E-03 -4.35E-04 2.02E-04 4.55E-05 -3.98E-06 S14 -1.05E+01 -3.79E-02 9.73E-03 -1.75E-03 -9.55E-05 6.55E-05 -1.84E-06 -9.39E-07

[0124] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, vertical chromatic aberration curve, MTF curve, and relative illumination curve of the optical lens 200 are shown in FIG. Fig. 9 , Fig.10 , Fig.11 , Fig.12 , Fig.13 , Fig.14 shown.

[0125] from Fig. 9 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.03mm, indicating that the optical lens can correct the field curvature well.

[0126] from Fig.10 It can be seen that the distortion of the optical lens is controlled within ±4%, indicating that the optical lens can correct the distortion well.

[0127] from Fig.11 It can be seen that the offset of axial aberration is controlled within ±0.02mm, which means that the optical lens can correct axial aberration well.

[0128] from Fig.12 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±5μm, indicating that the optical lens can correct chromatic aberration well.

[0129] from Fig.13 It can be seen that the MTF value of this embodiment is above 0.4 in the whole field of view. In the range of 0 to 200 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution capability in both low-frequency and high-frequency conditions.

[0130] from Fig.14 It can be seen that at the maximum half field of view angle, the relative illumination value of the optical lens is still greater than 60%, indicating that the optical lens has good relative illumination.

[0131] Example 3

[0132] See also Fig.15 , shown is a schematic structural diagram of an optical lens 300 provided in Example 3 of the present invention. The optical lens of this embodiment is substantially the same as that of Example 1, except that the object side surface S13 of the seventh lens L7 is a convex surface at the near optical axis; and the optical parameters such as the curvature radius, aspheric coefficient, and thickness of each lens surface are different.

[0133] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0134] Table 3-1

[0135]

[0136] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0137] Table 3-2

[0138] Face number K B C D E F G H S3 2.69E+00 2.14E-02 -1.99E-03 1.10E-04 4.20E-06 -4.42E-07 -4.21E-08 4.37E-09 S4 1.21E+00 1.61E-02 5.91E-04 1.72E-03 -8.53E-04 7.09E-05 6.04E-05 -1.27E-05 S5 8.10E+01 -2.43E-02 1.37E-03 -6.49E-04 8.15E-05 -5.21E-06 1.04E-05 -1.32E-06 S6 3.11E+00 -6.09E-03 3.33E-03 -1.32E-03 8.85E-04 -2.93E-04 5.28E-05 -3.92E-06 S9 -4.53E+00 -5.86E-02 1.40E-02 -5.42E-03 1.19E-03 2.76E-05 -2.64E-04 7.06E-05 S10 -2.37E+00 -4.37E-02 2.06E-02 -6.04E-03 1.08E-03 -1.94E-04 -3.87E-05 3.13E-06 S11 -3.88E-01 -1.32E-02 3.95E-03 -1.92E-04 -3.40E-04 -4.53E-07 2.75E-05 6.50E-06 S12 -4.45E-02 1.35E-02 -7.37E-03 3.21E-03 -1.06E-03 4.32E-05 7.33E-05 2.00E-05 S13 1.44E+02 -6.77E-02 9.50E-03 -3.01E-03 -4.52E-04 2.12E-04 6.20E-05 -3.08E-06 S14 -9.96E+00 -3.85E-02 9.75E-03 -1.76E-03 -9.64E-05 6.59E-05 -1.56E-06 -8.25E-07

[0139] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, vertical chromatic aberration curve, MTF curve, and relative illumination curve of the optical lens 300 are shown in FIG. Fig.16 , Fig.17 , Fig.18 , Fig.19 , Fig. 20 , Fig.21 shown.

[0140] from Fig.16 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.02mm, indicating that the optical lens can correct the field curvature well.

[0141] from Fig.17 It can be seen that the distortion of the optical lens is controlled within ±10%, indicating that the optical lens can correct the distortion well.

[0142] from Fig.18 It can be seen that the offset of axial aberration is controlled within ±0.01mm, which means that the optical lens can correct axial aberration well.

[0143] from Fig.19 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4μm, indicating that the optical lens can correct chromatic aberration well.

[0144] from Fig. 20 It can be seen that the MTF value of this embodiment is above 0.3 in the whole field of view. In the range of 0 to 200 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, and has good imaging quality and good detail resolution capability in both low-frequency and high-frequency conditions.

[0145] from Fig.21 It can be seen that at the maximum half field of view angle, the relative illumination value of the optical lens is still greater than 60%, indicating that the optical lens has good relative illumination.

[0146] Please refer to Table 4, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the chief ray incident angle CRA at the maximum image height, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0147] Table 4

[0148] Parameters and Conditionals Example 1 Example 2 Example 3 f(mm) 1.42 1.36 1.38 FOV(°) 200.00 200.00 200.00 EPD(mm) 0.79 0.76 0.77 TTL(mm) 13.62 13.57 13.57 Fno 1.80 1.80 1.80 IH(mm) 4.40 4.60 4.20 CRA(°) 31.90 31.67 31.79 BFL(mm) 1.19 1.19 1.19 TTL / IH 3.10 2.95 3.23 IH / EPD 5.60 6.08 5.48 IH / f 3.11 3.38 3.04 BFL / f 0.84 0.88 0.86 (FOV×f) / IH(°) 64.32 59.18 65.71 f1 / f -5.23 -5.46 -4.73 f2 / f -3.11 -3.24 -4.01 f3 / f -5.05 -7.11 -16.38 f4 / f 3.29 2.83 3.21 f5 / f -20.73 -8.11 -4.75 f6 / f 1.79 1.86 1.83 f7 / f -2.74 -5.67 -3.63 f123 / f -0.93 -1.10 -1.45 f4567 / f 1.65 1.71 2.07 R3 / f -4.58 -4.77 -8.88 R4 / f 2.70 2.81 2.90 R5 / f -21.73 -22.66 -20.70 R6 / f 3.92 5.88 22.12 R5 / R6 -5.54 -3.85 -0.94 R3 / f2 1.47 1.47 2.22 R4 / f2 -0.87 -0.87 -0.72 (R9-R10) / (R9+R10) 0.10 0.16 0.33 (R3+R4) / (R3-R4) 0.26 0.26 0.51 (R5+R6) / (R5-R6) 0.69 0.59 -0.03 Sag3 / d3 0.02 0.01 0.20 Sag4 / d4 0.43 0.40 0.45 d1 / (IH / 2) / tan(FOV / 2) -0.53 -0.50 -0.59 f3 / CT34 -12.85 -15.04 -35.16

[0149] In summary of the above embodiments, the optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it is possible to 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-large field of view, small size, and high imaging quality.

[0150] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0151] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: 依次包括从物侧到成像面沿光轴的部分: A first lens with a negative optical power, having a convex object side and a concave image side; A second lens with a negative optical power, having a concave object side near the optical axis and a concave image side; A third lens with a negative optical power, having both an object side and an image side concave; A fourth lens with a positive optical power, having both an object side and an image side convex; A fifth lens with a negative optical power, having a convex object side and a concave image side; A sixth lens with a positive optical power, having both an object side and an image side convex; A seventh lens with a negative optical power, having a concave image side near the optical axis; Wherein, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.1 < (R3 + R4) / (R3 - R4) < 0.

8.

2. The optical lens according to claim 1, characterized in that: 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: 2.7 < TTL / IH < 3.

4.

3. The optical lens according to claim 1, characterized in that: The maximum field of view angle FOV of the optical lens, the effective focal length f of the optical lens, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 55° < (FOV × f) / IH < 70°.

4. The optical lens according to claim 1, characterized in that: The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: -18 < f3 / f < -4.

5.

5. The optical lens according to claim 1, characterized in that: The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -6.2 < f7 / f < -2.

5.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the combined focal length f123 of the first lens, the second lens, and the third lens satisfy: -1.6 < f123 / f < -0.8; the effective focal length f of the optical lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: 1.5 < f4567 / f < 2.

3.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the radius of curvature R3 of the object side of the second lens satisfy: -9.6 < R3 / f < -4.1; the effective focal length f of the optical lens and the radius of curvature R4 of the image side of the second lens satisfy: 2.4 < R4 / f < 3.

2.

8. The optical lens according to claim 1, characterized in that: The radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -6 < R5 / R6 < -0.

8.

9. The optical lens according to claim 1, characterized in that: The radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 0 < (R9 - R10) / (R9 + R10) < 0.

5.

10. The optical lens according to claim 1, characterized in that: The sagittal height Sag3 of the clear aperture of the object side of the second lens and the clear aperture diameter d3 of the object side of the second lens satisfy: 0 < Sag3 / d3 < 0.3; the sagittal height Sag4 of the clear aperture of the image side of the second lens and the clear aperture diameter d4 of the image side of the second lens satisfy: 0.3 < Sag4 / d4 < 0.6.

Images