Optical lens

Abstract

This invention provides an optical lens comprising seven lenses, arranged sequentially along the optical axis from the object side to the image plane: a first lens with negative optical power and a concave image-side surface; a second lens with positive optical power and a convex object-side surface; a third lens with negative optical power and both its object-side and image-side surfaces are concave; a fourth lens with positive optical power and both its object-side and image-side surfaces are convex; a fifth lens with positive optical power and both its object-side and image-side surfaces are convex; a sixth lens with negative optical power and both its object-side and image-side surfaces are convex; and a seventh lens with positive optical power and both its object-side and image-side surfaces are concave. The optical lens provided by this invention can improve the image quality of an optical lens, reduce aberrations, and enhance the image quality of the lens, giving it one or more advantages such as a large image plane, a large aperture, and high image quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] With the continuous improvement of people's requirements for driving experience, vehicle application type optical lenses are used more and more in intelligent driving, and vehicle optical lenses are constantly improving in the automobile industry.

[0003] Advanced Driver Assistance System (ADAS) plays an important role in intelligent driving, which collects environmental information through various lenses and sensors to ensure the safety of drivers. In addition to the requirements of light, thin, small shape and high pixel, high resolution of the existing ADAS system lens, the optical lens is required to be able to clearly image under low illumination conditions, so it is necessary to develop an optical lens with good imaging effect. SUMMARY

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

[0005] The technical scheme adopted by the present application is:

[0006] An optical lens, a total of seven lenses, including in order along the optical axis from the object side to the imaging surface:

[0007] The first lens with negative focal power, the image side surface is concave;

[0008] The second lens with positive focal power, the object side surface is convex;

[0009] The third lens with negative focal power, the object side surface is concave, and the image side surface is concave;

[0010] The fourth lens with positive focal power, the object side surface is convex, and the image side surface is convex;

[0011] The fifth lens with positive focal power, the object side surface is convex, and the image side surface is concave;

[0012] The sixth lens with negative focal power, the object side surface is convex, and the image side surface is concave;

[0013] The seventh lens with positive focal power, the object side surface is convex, and the image side surface is concave;

[0014] Wherein, the object side surface curvature radius R5 of the third lens and the image side surface curvature radius R6 of the third lens satisfy: -1<(R5+R6) / (R5-R6)<-0.5;

[0015] The object side surface radius of curvature R11 of the sixth lens and the image side surface radius of curvature R12 of the sixth lens satisfy: 1 < (R11+R12) / (R11-R12) < 1.1.

[0016] It is further preferred that the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.3 < TTL / f < 5.6; the total track length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 4.3 < TTL / IH < 4.9.

[0017] It is further preferred that the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.9 < f1 / f < -1.3; the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.9 < f2 / f < 2.8; the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.8 < f4 / f < 2.2.

[0018] It is further preferred that the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -2.8 < f3 / f < -2; the object side surface radius of curvature R5 of the third lens and the effective focal length f of the optical lens satisfy: -2.9 < R5 / f < -1.6; the image side surface radius of curvature R6 of the third lens and the effective focal length f of the optical lens satisfy: 8.4 < R6 / f < 41.

[0019] It is further preferred that the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.7 < f5 / f < 2; the object side surface radius of curvature R9 of the fifth lens and the effective focal length f of the optical lens satisfy: 1 < R9 / f < 1.2; the image side surface radius of curvature R10 of the fifth lens and the effective focal length f of the optical lens satisfy: 40 < R10 / f < 45.

[0020] It is further preferred that the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -1.7 < f6 / f < -1.4; the object side surface radius of curvature R11 of the sixth lens and the effective focal length f of the optical lens satisfy: 40 < R11 / f < 45; the image side surface radius of curvature R12 of the sixth lens and the effective focal length f of the optical lens satisfy: 0.9 < R12 / f < 1.2.

[0021] It is further preferred that the focal length f7 of the seventh lens satisfies: 2 < f7 / f < 2.3; the radius of curvature R13 of the object side surface of the seventh lens satisfies: 0.9 < R13 / f < 1.1; and the radius of curvature R14 of the image side surface of the seventh lens satisfies: 1.6 < R14 / f < 2.2.

[0022] It is further preferred that the combined focal length f123 of the first lens, the second lens and the third lens satisfies: -1.8 < f123 / f < -1.4; and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens satisfies: 0.8 < f4567 / f < 1.

[0023] It is further preferred that the focal length f2 of the second lens satisfies: -1.2 < f2 / f3 < -0.8; and the focal length f3 of the third lens satisfies: -1.9 < f2 / f6 < -1.1.

[0024] It is further preferred that the focal length f3 of the third lens satisfies: -1.5 < f3 / f4 < -0.9; and the focal length f6 of the sixth lens satisfies: 1.2 < f3 / f6 < 1.9.

[0025] The optical lens provided by the present application adopts seven lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as large target surface, large aperture, high imaging quality and the like. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0027] Figure 1 FIG. 1 is a structural schematic diagram of an optical lens according to an embodiment of the present application.

[0028] Figure 2 FIG. 2 is a field curvature curve of the optical lens according to the embodiment of the present application.

[0029] Figure 3 FIG. 3 is an F-Tan(Theta) distortion curve of the optical lens according to the embodiment of the present application.

[0030] Figure 4Axial aberration curve of the optical lens in Embodiment 1 of the present application.

[0031] Figure 5 Curvature of field curve of the optical lens in Embodiment 1 of the present application.

[0032] Figure 6 MTF curve of the optical lens in Embodiment 1 of the present application.

[0033] Figure 7 Structure diagram of the optical lens in Embodiment 2 of the present application.

[0034] Figure 8 Curvature of field curve of the optical lens in Embodiment 2 of the present application.

[0035] Figure 9 F-Tan(Theta) distortion curve of the optical lens in Embodiment 2 of the present application.

[0036] Figure 10 Axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0037] Figure 11 Curvature of field curve of the optical lens in Embodiment 2 of the present application.

[0038] Figure 12 MTF curve of the optical lens in Embodiment 2 of the present application.

[0039] Figure 13 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0040] Figure 14 Curvature of field curve of the optical lens in Embodiment 3 of the present application.

[0041] Figure 15 F-Tan(Theta) distortion curve of the optical lens in Embodiment 3 of the present application.

[0042] Figure 16 Axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0043] Figure 17 Curvature of field curve of the optical lens in Embodiment 3 of the present application.

[0044] Figure 18 MTF curve of the optical lens in Embodiment 3 of the present application.

[0045] Figure 19 Structure diagram of the optical lens in Embodiment 4 of the present application.

[0046] Figure 20Field curvature curve of the optical lens in Embodiment 4 of the present application.

[0047] Figure 21 F-Tan(Theta) distortion curve of the optical lens in Embodiment 4 of the present application.

[0048] Figure 22 Axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0049] Figure 23 Vignetting curve of the optical lens in Embodiment 4 of the present application.

[0050] Figure 24 MTF curve of the optical lens in Embodiment 4 of the present application.

[0051] Figure 25 Structure diagram of the optical lens in Embodiment 5 of the present application.

[0052] Figure 26 Field curvature curve of the optical lens in Embodiment 5 of the present application.

[0053] Figure 27 F-Tan(Theta) distortion curve of the optical lens in Embodiment 5 of the present application.

[0054] Figure 28 Axial aberration curve of the optical lens in Embodiment 5 of the present application.

[0055] Figure 29 Vignetting curve of the optical lens in Embodiment 5 of the present application.

[0056] Figure 30 MTF curve of the optical lens in Embodiment 5 of the present application.

[0057] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0058] For better understanding of the present application, various aspects of the present application will be described in more detail with reference to the drawings. It should be understood that these detailed descriptions are merely descriptive of embodiments of the present application and are not intended in any way to limit the scope of the present application. Throughout the specification, like drawing reference numerals refer to like elements. The expression “and / or” includes any and all combinations of one or more of the associated listed items.

[0059] It should be noted that in the present specification, the expressions first, second, third, etc. are merely used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0060] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0061] In this document, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the position of the convex surface is not specified, 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 specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0062] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", when used in this specification, mean that something is included, but do not exclude the presence of one or more additional features, elements, components, and / or combinations thereof. In addition, when the phrase "at least one of" appears, it is intended to mean that one or more of the listed features are present, but not excluding the presence of one or more additional features. Furthermore, when describing the embodiments of the present application, the word "may" is used to mean "one or more embodiments of the present application". Also, the word "exemplary" is intended to mean an example or an illustration.

[0063] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that the terms should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0064] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0065] The optical lens provided by the embodiments of the present application comprises seven lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface as the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens.

[0066] In some embodiments, the first lens can have a negative focal power, the object side surface can be concave or convex, and the image side surface can be concave. The second lens can have a positive focal power, the object side surface can be convex, the third lens can have a negative focal power, the object side surface can be concave, and the image side surface can be concave. The fourth lens can have a positive focal power, the object side surface can be convex, and the image side surface can be convex. The fifth lens can have a positive focal power, the object side surface can be convex, and the image side surface can be concave. The sixth lens can have a negative focal power, the object side surface can be convex, and the image side surface can be concave. The seventh lens can have a positive focal power, the object side surface can be convex, and the image side surface can be concave.

[0067] In some embodiments, the optical lens can further include a diaphragm, which can be located between the third lens and the fourth lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging. When the diaphragm is located between the third lens and the fourth lens, the correction of the diaphragm aberration is facilitated.

[0068] In some embodiments, the optical lens can further include a filter and a protective glass, which are sequentially arranged between the seventh lens and the imaging surface along the optical axis. The filter is used to filter out interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging. The protective glass plays a role in protecting the optical lens, preventing the photosensitive chip from being damaged, and can improve the impact resistance and scratch resistance of the optical lens, while having little effect on the imaging quality of the optical lens.

[0069] In some embodiments, the fifth lens and the sixth lens can be glued to form a glued lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens. It can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0070] In some embodiments, the object side surface curvature radius R5 of the third lens and the image side surface curvature radius R6 of the third lens satisfy: -1<(R5+R6) / (R5-R6)<-0.5. Satisfying the above range, the third lens is double-concave, has the function of diverging light rays, can disperse the central light rays and the edge light rays of each field of view, and can correct the aberration generated by the front end lens. More specifically, -0.93<(R5+R6) / (R5-R6)<-0.52.

[0071] In some embodiments, the sixth lens satisfies: 1 < (R11+R12) / (R11-R12) < 1.1. Satisfying the above range makes the light rays of the edge field have an upward trend, which is beneficial to the image point on the imaging surface being away from the optical axis, so as to realize the effect of matching a large chip, obtain a larger picture, effectively eliminate aberration, and improve the resolving power of the optical lens. More specifically, 1.04 < (R11+R12) / (R11-R12) < 1.07.

[0072] In some embodiments, the optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.3 < TTL / f < 5.6. Satisfying the above range can effectively limit the length of the lens, which is beneficial to the miniaturization of the optical lens. More specifically, 5.32 < TTL / f < 5.58.

[0073] In some embodiments, the optical total length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 4.3 < TTL / IH < 4.9. Satisfying the above range ensures that the lens has a larger image surface under the condition of the same total length, which can match a larger size imaging chip to realize high-definition imaging, and better realize the balance between the small total length and the large image surface of the lens. More specifically, 4.38 < TTL / IH < 4.89.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.9 < f1 / f < -1.3. Satisfying the above range, by setting the first lens to have negative refractive power, it is beneficial to the first lens to accommodate a larger angle of light and collect as much light as possible into the rear optical system, thereby realizing a large field of view while increasing the light flux. More specifically, -1.87 < f1 / f < -1.34.

[0075] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 1.9 < f2 / f < 2.8. Satisfying the above range limits the second lens to have appropriate positive refractive power, which has the effect of converging light rays and reducing the height of peripheral light rays, which is beneficial to the reduction of the aperture of the rear lens. More specifically, 1.91 < f2 / f < 2.76.

[0076] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.8 < f4 / f < 2.2. Satisfying the above range is beneficial to the convergence of light, which makes the divergent light smoothly enter the rear optical system and better realizes high-quality imaging of the lens; at the same time, it can effectively correct the distortion of the edge field, reduce the deformation degree of the edge of the captured picture, and improve the picture quality. More specifically, 1.87 < f4 / f < 2.16.

[0077] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -2.8 < f3 / f < -2; the curvature radius R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: -2.9 < R5 / f < -1.6; the curvature radius R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: 8.4 < R6 / f < 41. Meeting the above ranges has the effect of diverging light rays, can disperse the central rays and marginal rays of each field of view, and enables the rear optical system to have a larger light receiving surface to receive the light rays emerging from the image side surface of the third lens, realizing a larger light input amount, which is beneficial to increasing the relative illumination. More specifically, -2.72 < f3 / f < -2; -2.87 < R5 / f < -1.66; 8.46 < R6 / f < 40.1.

[0078] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.7 < f5 / f < 2; the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 1 < R9 / f < 1.2; the curvature radius R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 40 < R10 / f < 45. Meeting the above ranges defines that the fifth lens has an appropriate positive optical power and a suitable surface shape, which is beneficial to light convergence. And the cooperation of the fifth lens with positive optical power and the sixth lens with negative optical power can adjust the optical path difference between different fields of view, improve the resolution, is beneficial to making the light enter the rear lens smoothly, and further can reduce the field curvature and correct the off-axis aberration of the optical lens. More specifically, 1.78 < f5 / f < 1.97; 1.03 < R9 / f < 1.15; 40.11 < R10 / f < 44.39.

[0079] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -1.7 < f6 / f < -1.4; the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 40 < R11 / f < 45; the curvature radius R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.9 < R12 / f < 1.2. Meeting the above ranges defines that the sixth lens has an appropriate negative optical power and a suitable surface shape, can diverge the light rays emerging from the fifth lens, make the light rays in the marginal field of view show an upward trend, is beneficial to the image points on the imaging surface moving away from the optical axis, is beneficial to achieving the effect of matching with a large chip, obtaining a larger picture, can effectively eliminate aberrations, and improve the resolution ability of the optical lens. More specifically, -1.66 < f6 / f < -1.43; 40.11 < R11 / f < 44.39; 0.96 < R12 / f < 1.12.

[0080] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 2 < f7 / f < 2.3; the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.9 < R13 / f < 1.1; the radius of curvature R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 1.6 < R14 / f < 2.2. Satisfying the above ranges, it is defined that the seventh lens has a positive optical power, which is beneficial to the convergence of light rays, enables the light rays to smoothly transition to the rear, reduces the height of the light rays incident on the rear, slows down the upward trend of the light rays, avoids the light energy loss caused by the excessive main ray angle of the large field of view light rays when reaching the imaging surface, is beneficial to improving the illuminance of the edge field of view, and is beneficial to achieving a short overall optical length. More specifically, 2.07 < f7 / f < 2.24; 0.93 < R13 / f < 1.07; 1.65 < R14 / f < 2.17.

[0081] In some embodiments, the combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: -1.8 < f123 / f < -1.4; the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 0.8 < f4567 / f < 1. Satisfying the above ranges, by reasonably setting the focal lengths of the lens groups before and after the aperture, it is beneficial to balance various aberrations of the system and improve the overall imaging quality. More specifically, -1.8 < f123 / f < -1.48; 0.89 < f4567 / f < 0.95.

[0082] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -1.2 < f2 / f3 < -0.8. Satisfying the above ranges, by reasonably setting the focal length relationship between the second and third lenses, it is beneficial to the smooth transition of light rays, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens. More specifically, -1.12 < f2 / f3 < -0.83.

[0083] In some embodiments, the focal length f2 of the second lens and the focal length f6 of the sixth lens satisfy: -1.9 < f2 / f6 < -1.1. Satisfying the above ranges, by reasonably setting the focal length relationship between the second and sixth lenses, it is beneficial to the smooth transition of light rays, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens. More specifically, -1.9 < f2 / f6 < -1.17.

[0084] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -1.5 < f3 / f4 < -0.9; the focal length f3 of the third lens and the focal length f6 of the sixth lens satisfy: 1.2 < f3 / f6 < 1.9. Satisfying the above ranges, by reasonably setting the focal length relationships of the third, fourth, and sixth lenses, it is beneficial for the light to transition smoothly, and at the same time correct various aberrations of the optical lens, improving the imaging quality of the optical lens. More specifically, -1.43 < f3 / f4 < -0.93; 1.22 < f3 / f6 < 1.87.

[0085] 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: 1.7 < IH / EPD < 2.2. Satisfying the above range is beneficial for increasing the light passing amount, making the peripheral field and the central field brightness more uniform. More specifically, 1.75 < IH / EPD < 2.2.

[0086] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 1 < IH / f < 1.3. Satisfying the above range, controlling the image height and focal length of the optical lens within a reasonable range helps the optical lens to have the characteristic of a large image plane and improves the imaging quality. More specifically, 1.09 < IH / f < 1.22.

[0087] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.4 < BFL / f < 0.6. Satisfying the above range limits the optical lens to have an appropriate back focus, facilitating the reasonable arrangement of the positions of each lens and reducing the processing and assembly difficulty. More specifically, 0.45 < BFL / f < 0.57.

[0088] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.58 < ∑CT / TTL < 0.79. Satisfying the above range, reasonably configuring the total optical length of the optical lens and the sum of the thicknesses of each lens helps to achieve the characteristic of high pixels and improve the imaging quality of the optical lens.

[0089] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 3.13 < ΣCT / f < 4.14. Satisfying the above range can effectively correct the field curvature and distortion of the optical lens and improve the imaging quality of the optical lens.

[0090] In some embodiments, the optical lens satisfies the following conditional expressions: 6.7 mm < f < 7.5 mm; 3.7 mm < EPD < 4.7 mm; 35 mm < TTL < 41 mm; 1.5 < Fno < 1.9; 26° < CRA < 29°; 3.4 mm < BFL < 3.9 mm; 60° < FOV < 75°; 8 mm < IH < 8.5 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the chief ray angle of incidence of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field angle of the optical lens, and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as a large target surface, a large aperture, and a long focal length characteristic. More specifically, 6.75 mm < f < 7.49 mm; 3.74 mm < EPD < 4.68 mm; 35.9 mm < TTL < 40.1 mm; 1.59 < Fno < 1.81; 26.86° < CRA < 28.66°; 3.41 mm < BFL < 3.81 mm; 63° < FOV < 73°; 8.1 mm < IH < 8.3 mm.

[0091] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, due to the low dispersion characteristic of the glass itself, the geometric chromatic aberration of the optical system can be effectively corrected. The optical lens provided by the present invention can adopt an all-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0092] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical 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 achieving the miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens of the present invention adopt spherical lenses, and the seventh lens adopts an aspherical lens.

[0093] 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 equation:

[0094]

[0095] Where 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 vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, and F are the fourth, sixth, eighth, tenth, and twelfth order surface coefficients, respectively.

[0096] The present invention will be further described below with reference to several 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 tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0097] Example 1

[0098] Please see Figure 1 The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane, the following components in sequence: 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, a filter G1, and a protective glass G2.

[0099] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0100] The second lens L2 has positive optical power, its object side S3 is convex, and its image side S4 is concave.

[0101] The third lens L3 has negative optical power, its object side S5 is concave, and its image side S6 is concave.

[0102] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is convex.

[0103] The fifth lens L5 has positive optical power, its object side S9 is convex, and its image side is concave.

[0104] The sixth lens L6 has negative optical power, its object side is convex, and its image side S11 is concave.

[0105] The fifth lens L5 and the sixth lens L6 form a cemented lens group with positive optical power, that is, the cemented surface of the image side of the fifth lens L5 and the object side of the sixth lens L6 is S10.

[0106] The seventh lens L7 has positive optical power, its object side surface S12 is convex, and its image side surface S13 is concave.

[0107] The object-side surface S14 and the image-side surface S15 of filter G1 are both planar.

[0108] The object side S16 and the image side S17 of the protective glass G2 are both flat.

[0109] The imaging plane S18 is a plane.

[0110] The seventh lens L7 is a glass aspherical lens, while the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are glass spherical lenses.

[0111] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0112] Table 1-1

[0113]

[0114]

[0115] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0116] Table 1-2

[0117] Face number K B C D E F S12 -4.92E+00 1.60E-03 -8.27E-05 4.30E-06 -2.22E-07 4.27E-09 S13 1.71E+00 8.94E-04 3.62E-06 1.14E-06 -1.13E-07 3.80E-09

[0118] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown.

[0119] Figure 2 The field curvature curve of Example 1 is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.03 mm, indicating that the optical lens 100 can effectively correct the field curvature.

[0120] Figure 3 The F-Tan (Theta) distortion curve of Example 1 is shown, which represents the distortion of light of different wavelengths at different image heights on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the distortion of the optical lens is controlled within -10% to 0, indicating that the optical lens 100 can effectively correct distortion.

[0121] Figure 4 The axial aberration curve of Embodiment 1 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. As can be seen from the figure, the axial aberration offset is controlled within -0.01 mm to 0.02 mm, indicating that the optical lens 100 can correct the axial aberration well.

[0122] Figure 5 The diagram shows the transverse chromatic aberration curves for Example 1, representing the chromatic aberration of each wavelength relative to the center wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the diagram, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1 μm to 3 μm, indicating that the optical lens 100 can correct chromatic aberration very well.

[0123] Figure 6 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents MTF value. As can be seen from the figure, the MTF value of this example is above 0.48 throughout the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, exhibiting good imaging quality and good detail resolution at both low and high frequencies.

[0124] Example 2

[0125] Please see Figure 7 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0126] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0127] Table 2-1

[0128]

[0129] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0130] Table 2-2

[0131] Face number K B C D E F S12 -4.76E+00 1.60E-03 -8.28E-05 4.36E-06 -2.28E-07 4.41E-09 S13 1.92E+00 8.81E-04 4.43E-06 1.03E-06 -1.06E-07 3.54E-09

[0132] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 200 are respectively as follows: Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 As shown.

[0133] from Figure 8 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.03mm, indicating that the optical lens 200 can effectively correct the field curvature.

[0134] from Figure 9 As can be seen, the distortion of the optical lens is controlled within -12% to 0, indicating that the optical lens 200 can effectively correct distortion.

[0135] from Figure 10 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens 200 can effectively correct axial aberration.

[0136] from Figure 11 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 3μm, indicating that the optical lens 200 can correct chromatic aberration very well.

[0137] from Figure 12 As can be seen, the MTF value of this embodiment is above 0.45 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0138] Example 3

[0139] Please see Figure 13 The figure shows a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side S1 of the first lens L1 is concave, the image side S4 of the second lens L2 is convex, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0140] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0141] Table 3-1

[0142]

[0143] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0144] Table 3-2

[0145] Face number K B C D E F S12 -6.65E+00 1.74E-03 -1.01E-04 5.48E-06 -2.48E-07 4.76E-09 S13 4.19E+00 7.51E-04 -9.52E-06 2.69E-06 -2.08E-07 6.49E-09

[0146] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 300 are respectively as follows: Figure 14 , Figure 15 , Figure 16 , Figure 17 , Figure 18 As shown.

[0147] from Figure 14 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.02mm, indicating that the optical lens 300 can effectively correct the field curvature.

[0148] from Figure 15 As can be seen, the distortion of the optical lens is controlled within -15% to 0, indicating that the optical lens 300 can effectively correct distortion.

[0149] from Figure 16 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens 300 can correct axial aberration well.

[0150] from Figure 17 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 2μm, indicating that the optical lens 300 can correct chromatic aberration very well.

[0151] from Figure 18 As can be seen, the MTF value of this embodiment is above 0.48 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0152] Example 4

[0153] Please see Figure 19 The figure shows a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side S1 of the first lens L1 is concave, the image side S4 of the second lens L2 is convex, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0154] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0155] Table 4-1

[0156]

[0157]

[0158] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0159] Table 4-2

[0160] Face number K B C D E F S12 -5.54E+00 1.51E-03 -7.90E-05 4.19E-06 -2.05E-07 4.11E-09 S13 -2.52E+00 1.05E-03 -2.59E-06 1.87E-06 -1.30E-07 3.70E-09

[0161] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 400 are respectively as follows: Figure 20 , Figure 21 , Figure 22 , Figure 23 , Figure 24 As shown.

[0162] from Figure 20 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.02mm, indicating that the optical lens 400 can effectively correct the field curvature.

[0163] from Figure 21 As can be seen, the distortion of the optical lens is controlled within -18% to 0, indicating that the optical lens 400 can effectively correct distortion.

[0164] from Figure 22 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens 400 can correct axial aberration well.

[0165] from Figure 23 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 2μm, indicating that the optical lens 400 can correct chromatic aberration very well.

[0166] from Figure 24 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0167] Example 5

[0168] Please see Figure 25The figure shows a schematic diagram of the structure of the optical lens 500 provided in Embodiment 5 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side S1 of the first lens L1 is concave, the image side S4 of the second lens L2 is convex, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0169] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0170] Table 5-1

[0171]

[0172]

[0173] The surface profile parameters of the aspherical lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0174] Table 5-2

[0175] Face number K B C D E F S12 -7.43E+00 2.09E-03 -1.38E-04 7.27E-06 -2.90E-07 4.70E-09 S13 2.34E+00 7.74E-04 -3.70E-05 6.90E-06 -5.15E-07 1.50E-08

[0176] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 500 are respectively as follows: Figure 26 , Figure 27 , Figure 28 , Figure 29 , Figure 30 As shown.

[0177] from Figure 26 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.03mm, indicating that the optical lens 500 can effectively correct the field curvature.

[0178] from Figure 27 As can be seen, the distortion of the optical lens is controlled within -15% to 0, indicating that the optical lens 500 can effectively correct distortion.

[0179] from Figure 28 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens 500 can correct axial aberration well.

[0180] from Figure 29 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 2μm, indicating that the optical lens 500 can correct chromatic aberration very well.

[0181] from Figure 30As can be seen, the MTF value of this embodiment is above 0.45 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0182] Please refer to Table 6 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, principal ray incident angle CRA at the maximum image height, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0183] Table 6

[0184]

[0185]

[0186] In summary, the optical lens provided by the present invention employs seven lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as large target surface, large aperture, and high imaging quality.

[0187] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions 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 one or more embodiments or examples.

[0188] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens, in total seven pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, the optical lens comprises in sequence: a first lens with negative refractive power, an image-side surface of which is a concave surface; a second lens with positive refractive power, an object-side surface of which is a convex surface; a third lens with negative refractive power, an object-side surface of which is a concave surface, and an image-side surface of which is a concave surface; a fourth lens with positive refractive power, an object-side surface of which is a convex surface, and an image-side surface of which is a convex surface; a fifth lens with positive refractive power, an object-side surface of which is a convex surface, and an image-side surface of which is a concave surface; a sixth lens with negative refractive power, an object-side surface of which is a convex surface, and an image-side surface of which is a concave surface; a seventh lens with positive refractive power, an object-side surface of which is a convex surface, and an image-side surface of which is a concave surface; wherein a curvature radius R5 of the object-side surface of the third lens and a curvature radius R6 of the image-side surface of the third lens satisfy -1 < (R5+R6) / (R5-R6) < -0.5; a curvature radius R11 of the object-side surface of the sixth lens and a curvature radius R12 of the image-side surface of the sixth lens satisfy 1 < (R11+R12) / (R11-R12) < 1.1; and an optical total length TTL of the optical lens and a real image height IH corresponding to a maximum field angle of the optical lens satisfy 4.3 < TTL / IH < 4.

9.

2. The optical lens of claim 1, wherein, An optical total length TTL of the optical lens and an effective focal length f of the optical lens satisfy 5.3 < TTL / f < 5.

6.

3. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a focal length f1 of the first lens satisfy -1.9 < f1 / f < -1.3; a focal length f2 of the second lens and the effective focal length f of the optical lens satisfy 1.9 < f2 / f < 2.8; and a focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy 1.8 < f4 / f < 2.

2.

4. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and a focal length f3 of the third lens satisfy -2.8 < f3 / f < -2; a curvature radius R5 of the object-side surface of the third lens and the effective focal length f of the optical lens satisfy -2.9 < R5 / f < -1.6; and a curvature radius R6 of the image-side surface of the third lens and the effective focal length f of the optical lens satisfy 8.4 < R6 / f < 41.

5. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and a focal length f5 of the fifth lens satisfy 1.7 < f5 / f < 2; a curvature radius R9 of the object-side surface of the fifth lens and the effective focal length f of the optical lens satisfy 1 < R9 / f < 1.2; and a curvature radius R10 of the image-side surface of the fifth lens and the effective focal length f of the optical lens satisfy 40 < R10 / f < 45.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and a focal length f6 of the sixth lens satisfy -1.7 < f6 / f < -1.4; a curvature radius R11 of the object-side surface of the sixth lens and the effective focal length f of the optical lens satisfy 40 < R11 / f < 45; and a curvature radius R12 of the image-side surface of the sixth lens and the effective focal length f of the optical lens satisfy 0.9 < R12 / f < 1.

2.

7. The optical lens of claim 1, wherein, A focal length f7 of the seventh lens and an effective focal length f of the optical lens satisfy: 2 < f7 / f < 2.3; a radius of curvature R13 of an object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.9 < R13 / f < 1.1; and a radius of curvature R14 of an image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 1.6 < R14 / f < 2.

2.

8. The optical lens of claim 1, wherein, A combined focal length f123 of the first lens, the second lens and the third lens and the effective focal length f of the optical lens satisfy: -1.8 < f123 / f < -1.4; and a combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 0.8 < f4567 / f < 1.

9. The optical lens of claim 1, wherein, A focal length f2 of the second lens and a focal length f3 of the third lens satisfy: -1.2 < f2 / f3 < -0.8; and the focal length f2 of the second lens and a focal length f6 of the sixth lens satisfy: -1.9 < f2 / f6 < -1.

1.

10. The optical lens of claim 1, wherein, A focal length f3 of the third lens and a focal length f4 of the fourth lens satisfy: -1.5 < f3 / f4 < -0.9; and the focal length f3 of the third lens and the focal length f6 of the sixth lens satisfy: 1.2 < f3 / f6 < 1.9.

Images