Optical lens

Abstract

The invention provides an optical lens, which sequentially comprises a first lens with positive focal power from an object side to an imaging surface along an optical axis, a second lens with negative focal power, a third lens with positive focal power and a fourth lens with negative focal power from the object side to the imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has negative focal power; the fourth lens has negative focal power, the object side surface of the fourth lens is a convex surface near the optical axis, and the image side surface of the fourth lens is a concave surface near the optical axis; the fifth lens has positive focal power, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power; 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 effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens meet the following conditions: 1.3 lt; iH / flt; and 1.6. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

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] With the popularity of remote work and online education, video conferencing has become an indispensable part of people's daily life and work, and the quality of video conferencing depends largely on the optical lens of the video conferencing, which puts higher requirements on the video conferencing lens. For example, in order to provide clear video quality, video conferencing lenses usually need to provide high resolution, such as 1080p or 4K; for example, in order to effectively capture the participants in the conference room, the video conferencing lens is often required to better blur the background and highlight the main body of the participants; in order to provide good video quality in a dimly lit environment, the video conferencing lens is usually required to have a larger aperture. Traditional video conferencing lenses have more or less some limitations, such as low resolution and poor imaging in low light or dim environments. Therefore, there is an urgent need to provide an optical lens that can meet the needs of video conferencing. Summary of the invention

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

[0004] The present invention provides an optical lens, which comprises seven lenses in total, and includes the following lenses in order from the object side to the imaging surface along the optical axis: The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; a third lens having negative optical power; a fourth lens element having negative optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; a fifth lens element having positive refractive power and a convex image-side surface; a sixth lens having negative optical power; The seventh lens element has a negative optical power and its image side surface is concave at the near optical axis; The effective focal length f of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy the following conditions: 1.3 <IH / f<1.6。

[0005] Further preferably, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.8 <TTL / IH<0.92。

[0006] Further preferably, the combined focal length f14 of the first lens, the second lens, the third lens, and the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f14 / f < 1.6.

[0007] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.85 < f1 / f < 1.05; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -2.

[0008] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -25 < f3 / f < -5.

[0009] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -28 < f4 / f < -2; the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: 1 < R7 / R8 < 1.7.

[0010] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 0.85.

[0011] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -10 < f6 / f < -1.8.

[0012] Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.8 < f7 / f < -0.5.

[0013] Further preferably, the true image height IH corresponding to the maximum field of view angle of the optical lens and the aperture value Fno of the optical lens satisfy: 6 mm < IH / Fno < 6.7 mm.

[0014] Further preferably, the focal length f1 of the first lens and the focal length f7 of the seventh lens satisfy: -1.8 < f1 / f7 < -1; the clear aperture DM11 of the object side surface of the first lens and the clear aperture DM72 of the image side surface of the seventh lens satisfy: 0.37 < DM11 / DM72 < 0.47.

[0015] Compared with the prior art, the optical lens provided by the present invention uses seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and enable the lens to have one or more advantages such as long focal length, large aperture, large image height, high pixel, and high imaging quality. Description of the Drawings

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

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

[0018] Figure 3 4 is a distortion curve diagram of the optical lens f~tan(θ) in Example 1 of the present invention.

[0019] Figure 4 Graph showing the axial aberration of the optical lens in Example 1 of the present invention.

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

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

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

[0023] Figure 8 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 2 of the present invention.

[0024] Fig. 9 Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

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

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

[0027] Fig.12 4 is an astigmatism curve diagram of the optical lens in Example 3 of the present invention.

[0028] Fig.13 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 3 of the present invention.

[0029] Fig.14 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

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

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

[0032] Fig.17 4 is an astigmatism curve diagram of the optical lens in Example 4 of the present invention.

[0033] Fig.18 4 is a distortion curve diagram of the optical lens f~tan(θ) in Example 4 of the present invention.

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

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

[0036] Fig.21 Schematic diagram of the structure of the optical lens in Example 5 of the present invention.

[0037] Fig. 22 4 is an astigmatism curve diagram of the optical lens in Example 5 of the present invention.

[0038] Fig.23 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 5 of the present invention.

[0039] Fig.24 Graph showing the axial aberration of the optical lens in Embodiment 5 of the present invention.

[0040] Fig.25 Graph showing the vertical axis chromatic aberration of the optical lens in Example 5 of the present invention.

[0041] Fig.26 Schematic diagram of the structure of the optical lens in Example 6 of the present invention.

[0042] Fig. 27 4 is an astigmatism curve diagram of the optical lens in Example 6 of the present invention.

[0043] Fig.28 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 6 of the present invention.

[0044] Fig.29 Graph showing the axial aberration of the optical lens in Embodiment 6 of the present invention.

[0045] Fig.30 Graph showing the vertical axis chromatic aberration of the optical lens in Example 6 of the present invention.

[0046] Fig.31 Schematic diagram of the structure of the optical lens in Example 7 of the present invention.

[0047] Fig.324 is an astigmatism curve diagram of the optical lens in Example 7 of the present invention.

[0048] Fig.33 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 7 of the present invention.

[0049] Fig.34 Graph showing the axial aberration of the optical lens in Embodiment 7 of the present invention.

[0050] Fig.35 Graph showing the vertical axis chromatic aberration of the optical lens in Example 7 of the present invention.

[0051] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] The optical lens provided by the embodiment of the present invention comprises seven lenses in total, and the optical lens comprises, in order from the object side to the imaging surface along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0060] In some embodiments, the first lens may have positive optical power, its object side surface is convex, and its image side surface is concave. The second lens may have negative optical power, its object side surface is convex, and its image side surface is concave. The third lens may have negative optical power, its object side surface may be concave or convex, and its image side surface may be concave or convex. The fourth lens may have negative optical power, its object side surface is convex at the near optical axis, and its image side surface is concave at the near optical axis. The fifth lens may have positive optical power, its object side surface may be concave or convex, and its image side surface is convex. The sixth lens may have negative optical power, its object side surface may be concave or convex, and its image side surface may be concave or convex. The seventh lens may have negative optical power, its object side surface may be concave or convex, and its image side surface is concave at the near optical axis.

[0061] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the object side and the first lens. It is understood that the aperture is used to limit the amount of incoming light to change the brightness of the image.

[0062] In some embodiments, the optical lens may further include a filter disposed between the seventh lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0063] 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 of the optical lens satisfy: 1.3 < IH / f < 1.6. Meeting the above conditions can enable the lens to have a large image plane and long focal length performance, and be able to match a larger-sized chip to achieve high-definition imaging.

[0064] In some embodiments, 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: 0.8 < TTL / IH < 0.92. Meeting the above conditions can better achieve the miniaturization of the lens. At the same time, when ensuring the same overall length of the lens, it has a large image plane and can match a larger-sized imaging chip to achieve high-definition imaging.

[0065] In some embodiments, the combined focal length f14 of the first lens, the second lens, the third lens, and the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f14 / f < 1.6. Meeting the above conditions is beneficial to the convergence of light, enabling the light entering the system from the front end to smoothly enter the rear optical system, making the overall light path more gentle, optimizing aberrations, and improving imaging resolution.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.85 < f1 / f < 1.05; the curvature radius R1 of the object side surface of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: 0.08 < R1 / R2 < 0.28. Meeting the above conditions can enable the first lens to have a large positive refractive power, while improving the ability to collect light in the marginal field of view, reducing the working aperture of the first lens, and being beneficial to achieving the balance of a large aperture and a small aperture.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -2; 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: 1.2 < R3 / R4 < 1.7. Meeting the above conditions, by reasonably setting the focal length and surface shape of the second lens, the incident light can be effectively diverged, avoiding excessive light deflection caused by the overly concentrated optical power of the first lens, and reducing the difficulty of aberration correction.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -25 < f3 / f < -5. Meeting the above conditions, by reasonably setting the focal length of the third lens, it is beneficial for the smooth transition of light, facilitating the correction of astigmatism and field curvature, and improving the imaging quality of the optical lens.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -28 < f4 / f < -2; the curvature radius R7 of the object side surface of the fourth lens and the curvature radius R8 of the image side surface of the fourth lens satisfy: 1 < R7 / R8 < 1.7. Meeting the above conditions, by reasonably setting the focal length and surface shape of the fourth lens, the incident light can be further diverged, the divergence of the light in the central field of view can be achieved, and at the same time, combined with the bending of the edge region of the fifth lens, the exit angle of the light in the edge field of view can be reduced, and the relative illumination of the edge field of view can be improved.

[0070] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 0.85. Meeting the above conditions, by setting the fifth lens to have a relatively large positive optical power, the incident light in the front end can be effectively converged, which is beneficial for correcting the aberration and distortion in the edge field of view brought by the front-end lens group, making the lens have a smaller distortion and capable of providing a high-definition imaging effect.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -10 < f6 / f < -1.8. Meeting the above conditions, by reasonably setting the focal length of the sixth lens, the light in the edge field of view can be effectively diverged, and at the same time, combined with the bending of the edge region of the seventh lens, the exit angle of the light in the edge field of view can be reduced, and the relative illumination of the edge field of view can be improved.

[0072] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.8 < f7 / f < -0.5. Meeting the above conditions, by setting the seventh lens to have a relatively large negative optical power, the incident light can be diverged to a greater extent, making the peripheral light and the central light turn upwards, reaching a higher imaging position, better realizing the large target surface imaging of the lens, and improving the imaging quality.

[0073] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens and the aperture value Fno of the optical lens satisfy: 6 mm < IH / Fno < 6.7 mm. Meeting the above conditions, the lens can better achieve the balance of large target surface imaging and large aperture performance, the pixel distribution can be sparser (i.e., the pixel size is larger), the noise can be reduced in a darker environment, the dynamic range will be wider, and more details can be retained in the dark part, thereby improving the picture quality.

[0074] In some embodiments, the focal length f1 of the first lens and the focal length f7 of the seventh lens satisfy: -1.8 < f1 / f7 < -1; the clear aperture DM11 of the object side surface of the first lens and the clear aperture DM72 of the image side surface of the seventh lens satisfy: 0.37 < DM11 / DM72 < 0.47. Meeting the above conditions, by reasonably setting the ratio of the focal lengths and apertures of the first and last lenses, the lens can have a smaller head size while having a larger imaging surface, and can better meet the balance between miniaturization and high pixels.

[0075] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.1 < TTL / f < 1.3. Meeting the above conditions can effectively limit the length of the lens and is beneficial to the miniaturization of the optical lens.

[0076] In some embodiments, the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -1 < R10 / f < -0.2. Meeting the above conditions is beneficial to better achieve the convergence of light, shorten the distance for light to reach the next lens, and is beneficial to reducing the overall optical length of the optical lens.

[0077] In some embodiments, 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: 0.2 < R14 / f < 3.2. Meeting the above conditions can appropriately suppress the angle of the marginal field incident on the imaging surface, effectively transmit more light beams to the imaging surface, and improve the relative illumination of the optical lens.

[0078] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.4 < f1 / f2 < -0.2. Meeting the above conditions, by reasonably distributing the focal lengths of the first and second lenses, it is beneficial to achieve the balance between the long focal length and high pixels of the optical lens, and is also beneficial to shortening the overall length of the optical lens.

[0079] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -0.3 < f5 / f6 < -0.05. Meeting the above conditions is beneficial to the smooth transition of light, and at the same time corrects various aberrations of the optical lens and improves the imaging quality of the optical lens.

[0080] In some embodiments, the overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.55 < ∑CT / TTL < 0.7. Meeting the above conditions can effectively compress the overall length of the optical lens, and is also beneficial to the structural design and production process of the optical lens.

[0081] 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: 2.4 < IH / EPD < 2.85. Meeting the above conditions can increase the width of the light beam entering the optical lens, improve the brightness at the image plane of the optical lens, and avoid the generation of vignetting.

[0082] In some embodiments, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.96 < (2 × f × tan(FOV / 2)) / IH < 1.02. Meeting the above conditions can make the lens have a small distortion value (such as a distortion value < 1%), reduce the degree of image deformation in the edge field of view, and provide a high-definition imaging effect.

[0083] In some embodiments, the combined focal length f13 of the first lens, the second lens, and the third lens and the combined focal length f14 of the first lens, the second lens, the third lens, and the fourth lens satisfy: 0.75 < f13 / f14 < 1.1. Meeting the above conditions is beneficial to balancing various aberrations of the lens and improving the overall imaging quality by reasonably balancing the proportion of the focal lengths of the first three lenses.

[0084] In some embodiments, the optical lens satisfies the conditional formula: 7.5 mm < f < 8.3 mm, 9.2 mm < TTL < 10.5 mm, 1.7 < Fno < 1.9, 10.5 mm < IH < 12 mm, 68° < FOV < 76°, where f represents the effective focal length of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, and FOV represents the maximum field of view angle of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least: a small overall optical length; a large imaging surface, which can be matched with a larger-sized chip to achieve high-definition imaging; a large aperture value, enabling the lens to achieve high-definition imaging even in a relatively dark environment; and the characteristics of long focal length and short depth of field, which can better blur the background and highlight the main body when shooting distant scenes or people.

[0085] In some embodiments, the seven lenses in the optical lens can all be plastic lenses or glass-plastic hybrid materials. Preferably, the optical lens of the present invention uses a seven-piece glass-plastic hybrid lens structure, which can make the optical lens better match the large target chip to achieve high-definition imaging, and can also achieve the miniaturization of the optical lens, a reasonable balance of large image surface and wide angle. Specifically, the first lens can be a glass lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are all plastic lenses; the glass-plastic hybrid structure can effectively reduce costs, correct aberrations, reduce volume, and provide a more cost-effective optical lens product.

[0086] 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 may be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of lenses, and better realizing miniaturization of lenses. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens in the optical lens provided by the present invention may be aspherical lenses.

[0087] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations: ; 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 See also Figure 1, shown is a schematic diagram of the structure of the optical lens 100 provided in Example 1 of the present invention, and the optical lens 100 includes, along the optical axis from the object side to the imaging surface S17, an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and a filter G1.

[0090] The first lens L1 has positive refractive power, its object side surface S1 is convex, and its image side surface S2 is concave; The second lens L2 has negative refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave; The third lens L3 has negative refractive power, its object-side surface S5 is concave, and its image-side surface S6 is convex; The fourth lens L4 has negative refractive power, an object-side surface S7 thereof is convex at the near optical axis, and an image-side surface S8 thereof is concave at the near optical axis; The fifth lens L5 has positive refractive power, its object-side surface S9 is convex at the near optical axis, and its image-side surface S10 is convex; The sixth lens L6 has negative refractive power, its object-side surface S11 is concave, and its image-side surface S12 is convex; The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis; The object side surface S15 and the image side surface S16 of the filter G1 are both planes; The imaging surface S17 is a plane.

[0091] The first lens L1 is a glass aspherical lens; the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all plastic aspherical lenses.

[0092] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0093] Table 1-1 The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0094] Table 1-2 In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0095] Figure 2 The astigmatism curve of the optical lens 100 in this embodiment is shown, which represents the astigmatism of light in the meridional image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the field angle (unit: °). It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1mm, indicating that the optical lens 100 can correct the astigmatism well.

[0096] Figure 3 The f~tan(θ) distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion of different field angles on the imaging surface, with the horizontal axis representing the distortion value (unit: %) and the vertical axis representing the field angle (unit: °). It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 100 can correct the distortion well.

[0097] 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 100 can correct the axial aberration well.

[0098] 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 (0.555 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 ±1 μm, indicating that the optical lens 100 can correct the chromatic aberration well.

[0099] Example 2 See also Figure 6 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0100] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0101] Table 2-1 The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0102] Table 2-2 In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 7 , Figure 8 , Fig. 9 , Fig.10 As shown. Figure 7 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 200 can correct the astigmatism well. Figure 8 It can be seen from the graph that the distortion value is controlled within ±1%, indicating that the optical lens 200 can correct the distortion well. Fig. 9 It can be seen from the graph that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 200 can correct the axial aberration well. Fig.10 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 200 can correct the chromatic aberration well.

[0103] Example 3 See also Fig.11 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object side surface S5 of the third lens L3 is convex at the near optical axis; the image side surface S6 of the third lens L3 is concave at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0104] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0105] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0106] Table 3-2 In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 300 are respectively as follows: Fig.12 , Fig.13 , Fig.14 , Fig.15 As shown. Fig.12 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 300 can correct the astigmatism well. Fig.13 It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 300 can correct the distortion well. Fig.14It can be seen from the graph that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 300 can correct the axial aberration well. Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 300 can correct the chromatic aberration well.

[0107] Example 4 See also Fig.16 , shown is a schematic diagram of the structure of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0108] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0109] Table 4-1 The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0110] Table 4-2 In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 400 are respectively as follows: Fig.17 , Fig.18 , Fig.19 , Fig. 20 As shown. Fig.17 It can be seen from the figure that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 400 can correct the astigmatism well. Fig.18 It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 400 can correct the distortion well. Fig.19 It can be seen from the graph that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 400 can correct the axial aberration well. Fig. 20 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1μm, indicating that the optical lens 400 can correct the chromatic aberration well.

[0111] Example 5 See also Fig.21 , shown is a schematic diagram of the structure of an optical lens 500 provided in Example 5 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the image side surface S6 of the third lens L3 is a concave surface at the near optical axis; the object side surface S13 of the seventh lens L7 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0112] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0113] Table 5-1 The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0114] Table 5-2 In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, and vertical axis chromatic aberration curve of the optical lens 500 are respectively as follows: Fig. 22 , Fig.23 , Fig.24 , Fig.25 As shown. Fig. 22 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 500 can correct the astigmatism well. Fig.23 It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 500 can correct the distortion well. Fig.24 It can be seen from the graph that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 500 can correct the axial aberration well. Fig.25 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 500 can correct the chromatic aberration well.

[0115] Example 6 See also Fig.26 , shown is a schematic diagram of the structure of an optical lens 600 provided in Example 6 of the present invention. Compared with Example 1, this embodiment has the following main differences: the image side surface S6 of the third lens L3 is a concave surface at the near optical axis; the object side surface S9 of the fifth lens L5 is a concave surface; the object side surface S13 of the seventh lens L7 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0116] The relevant parameters of each lens in the optical lens 600 in Example 6 are shown in Table 6-1.

[0117] Table 6-1 The surface parameters of the aspheric lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0118] Table 6-2 In this embodiment, the astigmatism curve, f-tan(θ) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 600 are respectively as follows: Fig. 27 , Fig.28 , Fig.29 , Fig.30 As shown. Fig. 27 It can be seen from the figure that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 600 can correct the astigmatism well. Fig.28 It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 600 can correct the distortion well. Fig.29 It can be seen from the graph that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 600 can correct the axial aberration well. Fig.30 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1μm, indicating that the optical lens 600 can correct the chromatic aberration well.

[0119] Example 7 See also Fig.31 , shown is a schematic diagram of the structure of an optical lens 700 provided in Example 7 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S11 of the sixth lens L6 is a convex surface at the near optical axis; the image-side surface S12 of the sixth lens L6 is a concave surface at the near optical axis; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0120] The relevant parameters of each lens in the optical lens 700 in Example 7 are shown in Table 7-1.

[0121] Table 7-1 The surface parameters of the aspheric lens of the optical lens 700 in Example 7 are shown in Table 7-2.

[0122] Table 7-2 In this embodiment, the astigmatism curve, f-tan(θ) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 700 are respectively as follows: Fig.32 , Fig.33 , Fig.34 , Fig.35 As shown. Fig.32 It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 700 can correct the astigmatism well. Fig.33 It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 700 can correct the distortion well. Fig.34It can be seen from the graph that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 700 can correct the axial aberration well. Fig.35 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1μm, indicating that the optical lens 700 can correct the chromatic aberration well.

[0123] Please refer to Table 8, 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.

[0124] Table 8 In summary of the above embodiments, the optical lens provided by the present invention adopts a seven-piece glass-plastic hybrid structure. Through a specific surface shape setting and a reasonable distribution of optical focal length, the structure of the optical lens is relatively compact, which effectively shortens the overall length of the optical lens and is conducive to miniaturization; it has a large aperture value, so that the lens can achieve high-definition imaging in a darker environment; at the same time, it has a large imaging surface and can match a larger chip to achieve high-definition imaging; it also has the characteristics of long focus and short depth of field, and when shooting distant scenes or people, it can better blur the background and highlight the subject. In addition, it can also reasonably correct the overall aberration of the optical lens, has the characteristics of small distortion and high pixels, and improves the imaging quality of the optical lens.

[0125] 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.

[0126] 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: It sequentially includes from the object side to the imaging surface along the optical axis: A first lens with positive optical power, whose object side is convex and whose image side is concave; A second lens with negative optical power, whose object side is convex and whose image side is concave; A third lens with negative optical power; A fourth lens with negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A fifth lens with positive optical power, whose image side is convex; A sixth lens with negative optical power; A seventh lens with negative optical power, whose image side is concave near the optical axis; Wherein, 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: 1.3 < IH / f < 1.

6.

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: 0.8 < TTL / IH < 0.

92.

3. The optical lens according to claim 1, characterized in that: The combined focal length f14 of the first lens, the second lens, the third lens and the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f14 / f < 1.

6.

4. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.85 < f1 / f < 1.05; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -4.5 < f2 / f < -2.

5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -25 < f3 / f < -5.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -28 < f4 / f < -2; the curvature radius R7 of the object side of the fourth lens and the curvature radius R8 of the image side of the fourth lens satisfy: 1 < R7 / R8 < 1.

7.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 0.

85.

8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -10 < f6 / f < -1.

8.

9. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.8 < f7 / f < -0.

5.

10. The optical lens according to claim 1, characterized in that: The true image height IH corresponding to the maximum field of view angle of the optical lens and the aperture value Fno of the optical lens satisfy: 6mm < IH / Fno < 6.7mm.

11. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the focal length f7 of the seventh lens satisfy: -1.8 < f1 / f7 < -1; the clear aperture DM11 of the object side of the first lens and the clear aperture DM72 of the image side of the seventh lens satisfy: 0.37 < DM11 / DM72 < 0.47.

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