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 fifth lens has negative focal power, and the image side surface of the fifth lens is a concave surface near the optical axis; the sixth lens has positive focal power, the object side surface of the sixth lens near the optical axis is a convex surface, and the image side surface of the sixth lens is a convex surface; and the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface near the optical axis. According to the optical lens provided by the invention, through specific surface shape setting and reasonable focal power distribution, the overall aberration of the optical lens can be reasonably corrected, so that the optical lens has one or more advantages of large image height, large aperture, miniaturization, high imaging quality and the like.

Description

Technical Field

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

[0002] With the development of science and technology, portable electronic products with a camera function are favored by more and more users, and users have higher and higher requirements for portable electronic products. The total length of the optical lens in the existing portable electronic products is relatively large, and the image height is relatively small, which limits the user's requirements for the thinness, lightness and clear imaging of high pixels on a large bottom of the portable electronic products, and has become a problem in the field of optical lens design.

[0003] Therefore, how to satisfy the characteristics of thinness, lightness, large image height and clear imaging at the same time is one of the problems that need to be solved urgently in the field of optical lenses. Summary of the Invention

[0004] In view of the above problems, the object of the present invention is to provide an optical lens, which has one or more advantages such as a large image height, a large aperture, miniaturization, and high imaging quality.

[0005] The technical solution adopted by the present invention is as follows: An optical lens, comprising a total of seven lenses, which sequentially include from the object side to the imaging surface along the optical axis: A first lens with a positive optical power, the object side surface thereof is a convex surface, and the image side surface thereof is a concave surface; A second lens with a negative optical power, the object side surface thereof is a convex surface, and the image side surface thereof is a concave surface; A third lens with a negative optical power; A fourth lens with a negative optical power; A fifth lens with a negative optical power, the image side surface thereof is a concave surface near the optical axis; A sixth lens with a positive optical power, the object side surface thereof is a convex surface near the optical axis, and the image side surface thereof is a convex surface; A seventh lens with a negative optical power, the object side surface thereof is a concave surface, and the image side surface thereof is a concave surface near the optical axis; Wherein, the total optical length TTL of the optical lens satisfies: 6.5 mm < TTL < 6.9 mm; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 12.8 mm < TTL × (IH / f) < 13.5 mm.

[0006] Further preferably, the total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 4.1 mm < TTL / Fno < 4.5 mm.

[0007] More preferably, the sagittal height SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens, the sagittal height SAGX62 corresponding to the maximum clear aperture semi-diameter at the image side end of the sixth lens, and the distance AT67 between the sixth lens and the seventh lens on the optical axis satisfy: -0.8 < (SAGX71 - SAGX62) / AT67 < -0.3.

[0008] More preferably, the overall optical length TTL of the optical lens, the maximum field of view FOV of the optical lens, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 1.2 < (TTL × tan(FOV / 2)) / (IH / 2) < 1.3.

[0009] More preferably, the clear aperture semi-diameter CSD11 at the object side end of the first lens, the clear aperture semi-diameter CSD61 at the object side end of the sixth lens, and the clear aperture semi-diameter CSD72 at the image side end of the seventh lens satisfy: 0.22 < CSD11 / (CSD61 + CSD72) < 0.23.

[0010] More preferably, the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, the central thickness CT4 of the fourth lens on the optical axis, and the central thickness CT5 of the fifth lens on the optical axis satisfy: 0.35 mm < (CT2 + CT3 + CT4 + CT5) / 4 < 0.55 mm.

[0011] More preferably, the focal length f6 of the sixth lens, the focal length f7 of the seventh lens, and the focal length f5 of the fifth lens satisfy: 0.02 < (f6 + f7) / f5 < 0.07.

[0012] More preferably, the central thickness CT6 of the sixth lens and the edge thickness ET6 of the sixth lens satisfy: 1.8 < CT6 / ET6 < 3.5.

[0013] More preferably, the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 2 < ∑CT / ∑AT < 3.

[0014] More preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -30 < f4 / f < -9; the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2.1 < f5 / f < -1.3.

[0015] Compared with the prior art, the optical lens provided by the present invention has a small size through a specific surface shape setting and a reasonable optical focal length distribution; it can also achieve a large image height of the lens and can be matched with a large target surface chip, which is beneficial to improving the lens resolution and image detail restoration; the lens has a large aperture, and high-definition imaging can be achieved even in dim environments; it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has high pixels and improves the imaging quality of the optical lens. BRIEF 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 Embodiment 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 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] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] The optical lens provided by the embodiment of the present invention has a total of seven lenses, which are, in order from the object side to the imaging surface along the optical axis, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens.

[0050] In some embodiments, the first lens may have a positive optical power, its object side is convex, and its image side is concave. The second lens may have a negative optical power, its object side is convex, and its image side is concave. The third lens may have a negative optical power, its object side may be concave or convex, and its image side may be concave or convex. The fourth lens may have a negative optical power, its object side may be concave or convex, and its image side may be concave or convex. The fifth lens may have a negative optical power, its object side may be concave or convex, and its image side is concave near the optical axis. The sixth lens may have a positive optical power, its object side is convex near the optical axis, and its image side is convex. The seventh lens may have a negative optical power, its object side is concave, and its image side is concave near the optical axis.

[0051] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the object side and the first lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image.

[0052] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the seventh lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0053] In some embodiments, the total optical length TTL of the optical lens satisfies: 6.5 mm < TTL < 6.9 mm; the total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens, and the effective focal length f of the optical lens satisfy: 12.8 mm < TTL × (IH / f) < 13.5 mm. Satisfying the above conditional expressions ensures that the optical lens has a smaller total length and a larger image height, and controlling the relationship between the image height and the focal length ensures that the optical lens achieves a balance between small volume and high pixels, enabling the optical lens to have the characteristics of a large bottom, high pixels, and being thin and light.

[0054] In some embodiments, the total optical length TTL of the optical lens and the f-number Fno of the optical lens satisfy: 4.1 mm < TTL / Fno < 4.5 mm. Satisfying the above conditional expressions, by controlling the relationship between the total length of the optical lens and the f-number, it is ensured that the optical lens can meet the requirements of large aperture and thin and light design, enabling the optical lens to obtain sufficient light transmission in a dim environment and meet the needs of high-quality and high-definition shooting.

[0055] In some embodiments, the sag SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens, the sag SAGX62 corresponding to the maximum clear aperture semi-diameter at the image side end of the sixth lens, and the spacing AT67 between the sixth lens and the seventh lens on the optical axis satisfy: -0.8 < (SAGX71 - SAGX62) / AT67 < -0.3. Satisfying the above conditional formula can reasonably configure the sags of the image side surface of the sixth lens and the object side surface of the seventh lens and the air gap, which is beneficial to the effective deflection of light rays between the sixth lens and the seventh lens, thereby facilitating the reduction of the chief ray angle on the imaging surface of the optical lens, and further effectively correcting the aberration of the peripheral field of view and improving the imaging quality.

[0056] In some embodiments, the total optical length TTL of the optical lens, the maximum field of view FOV of the optical lens, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 1.2 < (TTL × tan(FOV / 2)) / (IH / 2) < 1.3. Satisfying the above conditional formula can effectively balance the requirements of the image height and the total optical length of the optical lens, effectively limit the length of the optical lens, and is beneficial to the miniaturization of the optical lens; at the same time, by controlling the maximum field of view of the optical lens and the true image height corresponding to the maximum field of view, the optical distortion of the optical lens can be controlled and the imaging reduction degree of the lens can be improved.

[0057] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens, the clear aperture semi-diameter CSD61 at the object side end of the sixth lens, and the clear aperture semi-diameter CSD72 at the image side end of the seventh lens satisfy: 0.22 < CSD11 / (CSD61 + CSD72) < 0.23. Satisfying the above conditional formula, by restricting the ratio of the clear aperture semi-diameter at the object side end of the first lens to the sum of the clear aperture semi-diameters at the object side end of the sixth lens and the image side end of the seventh lens, reasonably controlling the dimensions of the front and rear ends of the optical lens in the direction perpendicular to the optical axis, can ensure that the entire optical lens has a small size and ensure that the optical lens meets the miniaturization requirements.

[0058] In some embodiments, the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, the central thickness CT4 of the fourth lens on the optical axis, and the central thickness CT5 of the fifth lens on the optical axis satisfy: 0.35 mm < (CT2 + CT3 + CT4 + CT5) / 4 < 0.55 mm. Satisfying the above conditional formula, by setting the central thicknesses of the second lens, the third lens, the fourth lens, and the fifth lens within a reasonable range, it not only ensures that each lens meets the processing performance, but also ensures the ultra-thin characteristics of each lens, and further enables the optical lens to meet the ultra-thin design requirements.

[0059] In some embodiments, the focal length f6 of the sixth lens, the focal length f7 of the seventh lens, and the focal length f5 of the fifth lens satisfy: 0.02 < (f6 + f7) / f5 < 0.07. Satisfying the above conditional formula makes the deflection of light rays in each field of view on the surfaces of the fifth lens, the sixth lens, and the seventh lens smoother, effectively reducing total internal reflection of light rays and ghost images on the lens surface, and better complementarily eliminating positive and negative spherical aberrations and chromatic aberration of magnification in different fields of view, thereby improving the imaging quality.

[0060] In some embodiments, the central thickness CT6 of the sixth lens and the edge thickness ET6 of the sixth lens satisfy: 1.8 < CT6 / ET6 < 3.5. Satisfying the above conditional formula can reasonably control the ratio of the central thickness to the edge thickness of the sixth lens, thereby controlling the overall thickness of the sixth lens and avoiding a situation where the ratio gap between the central thickness and the edge thickness is too large, which is not conducive to processing and assembly.

[0061] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances between any two adjacent lenses among the first lens to the seventh lens on the optical axis satisfy: 2 < ∑CT / ∑AT < 3. Satisfying the above conditional formula can effectively reduce the size of the optical lens, avoid the optical lens from being too large in volume, and at the same time can reduce the assembly difficulty of the lenses, enabling the optical lens to achieve a high space utilization rate.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -30 < f4 / f < -9; the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2.1 < f5 / f < -1.3. Satisfying the above conditional formula, by setting the fourth lens and the fifth lens with negative optical power, it can ensure that when large-angle light rays are incident on the optical lens, they can spread smoothly, improve the image plane brightness of the large-angle field of view, and at the same time is conducive to correcting the aberration generated by the refraction of light rays through the front lenses, thereby improving the resolution of the optical lens.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.4 < f6 / f < 0.6. Satisfying the above conditional formula, the sixth lens provides positive optical power for the optical lens. As the penultimate lens of the optical lens, it can converge the light beam emitted by the front lenses, smoothly transfer the light beam to the seventh lens, and avoid large field curvature in the edge field of view.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.7 < f7 / f < -0.5. Satisfying the above conditional formula is conducive to the seventh lens cooperating with the foregoing lenses to shorten the back focal length and realize the miniaturized design of the optical system.

[0065] In some embodiments, the focal length f1 of the first lens, 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: 0.6 < f1 / (R1 + R2) < 0.8. Satisfying the above conditional formula can constrain the surface profiles of the object side surface and the image side surface of the first lens, which is beneficial to reducing the bending degree of light at the image side surface of the first lens and decreasing the incident angle of light on the lens, so as to balance the high-order aberrations of the optical lens and further ensure that the optical lens has excellent imaging quality.

[0066] In some embodiments, the clear aperture diameter CSD11 at the object side end of the first lens and the clear aperture diameter CSD71 at the object side end of the seventh lens satisfy: 0.4 < CSD11 / CSD71 < 0.45. Satisfying the above conditional formula can make the optical lens have a smaller aperture size, which is convenient for being mounted on thin and light electronic devices.

[0067] 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: 2.9 < IH / EPD < 3.2. Satisfying the above conditional formula can make the optical lens with a large image plane have a larger entrance pupil diameter and a higher light passing amount, and further improve the imaging effect when the optical lens works in a dark environment.

[0068] 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 on the optical axis respectively satisfy: 1.6 < TTL / ∑CT < 1.8. Satisfying the above conditional formula and reasonably configuring the overall optical length of the optical lens and the sum of the thicknesses of each lens helps to achieve high pixel characteristics and improve the imaging quality of the optical lens; at the same time, it can effectively shorten the overall optical length of the optical lens and meet the requirements of miniaturization and lightweight design.

[0069] In some embodiments, the optical lens satisfies the conditional formula: 5mm < f < 5.5mm, 1.5 < Fno < 1.65, 10mm < IH < 10.6mm; where f represents the effective focal length of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, and Fno represents the aperture value of the optical lens. Satisfying the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least one or more advantages among large aperture, large image height, and large bottom high pixel characteristics.

[0070] In some embodiments, the lens material in the optical lens provided by the present invention may be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt a full plastic lens structure, which not only makes the lens have excellent imaging performance, but also makes the structure of the lens more compact, and can better achieve a balance between miniaturization of the lens and high image quality.

[0071] 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 reducing 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 of the present invention may all be aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and reducing the size of lenses, and better realizing miniaturization of lenses.

[0072] 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.

[0073] 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.

[0074] Example 1 See also Figure 1 , which is a schematic diagram of the structure of the optical lens 100 provided in Embodiment 1 of the present invention, wherein the optical lens includes, in sequence from the object side to the imaging surface along the optical axis: 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.

[0075] 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, an object-side surface S5 thereof is convex at the near optical axis, and an image-side surface S6 thereof is concave at the near optical axis; 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 negative refractive power, an object-side surface S9 thereof is convex at the near optical axis, and an image-side surface S10 thereof is concave at the near optical axis; The sixth lens L6 has positive refractive power, its object-side surface S11 is convex at the near optical axis, 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.

[0076] The first lens L1, 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.

[0077] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0078] Table 1-1 The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0079] Table 1-2 In this embodiment, the astigmatism curve, f-tan(θ) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0080] Figure 2The astigmatism curve of Example 1 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 -0.05mm~0.1mm, indicating that the optical lens 100 can correct astigmatism well.

[0081] Figure 3 The f~tan(θ) distortion curve of Example 1 is shown, which represents the f~tan(θ) distortion at different image heights on the imaging surface, the horizontal axis represents the f~tan(θ) distortion value (unit: %), and the vertical axis represents the field of view angle (unit: °). It can be seen from the figure that the f~tan(θ) distortion of the optical lens 100 is controlled within 0~2%, indicating that the distortion of the optical lens 100 is well corrected.

[0082] Figure 4 The axial aberration curve of the present 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 offset of the axial aberration is controlled within -0.05mm~0.03mm, indicating that the optical lens 100 can better correct the axial aberration.

[0083] Figure 5 The vertical chromatic aberration curve of Example 1 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 chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 100 can perfectly correct the chromatic aberration of each field of view.

[0084] 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 differences of this embodiment are: the object side surface S5 of the third lens L3 is a concave surface; the image side surface S6 of the third lens L3 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0085] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0086] Table 2-1 The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0087] 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 shown.

[0088] from Figure 7 It can be seen that the astigmatism of the meridional image plane and the sagittal image plane is controlled within -0.1mm~0.15mm, which means that the optical lens 200 can correct the astigmatism well.

[0089] from Figure 8 It can be seen that the f~tan(θ) distortion of the optical lens 100 is controlled within 0~2%, indicating that the distortion of the optical lens 200 is well corrected.

[0090] from Fig. 9 It can be seen that the offset of the axial aberration is controlled within -0.05mm~0.03mm, which means that the optical lens 200 can correct the axial aberration well.

[0091] from Fig.10 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 200 can extremely well correct the chromatic aberration of each field of view.

[0092] Example 3 See also Fig.11 , which 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 a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0093] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0094] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0095] 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 shown.

[0096] from Fig.12 It can be seen 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.

[0097] from Fig.13 It can be seen that the f~tan(θ) distortion of the optical lens 300 is controlled within 0~2%, indicating that the distortion of the optical lens 300 is well corrected.

[0098] from Fig.14 It can be seen that the offset of the axial aberration is controlled within -0.06mm~0.04mm, which means that the optical lens 300 can correct the axial aberration well.

[0099] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -2μm~4μm, which means that the optical lens 300 can perfectly correct the chromatic aberration of each field of view.

[0100] Example 4 See also Fig.16 , shown is a schematic diagram of the structure of the optical lens 400 provided in Example 4 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 a concave surface; the object-side surface S7 of the fourth lens L4 is a concave surface; the image-side surface S8 of the fourth lens L4 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0101] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0102] Table 4-1 The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0103] 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 shown.

[0104] from Fig.17It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within -0.15mm~0.1mm, which means that the optical lens 400 can correct the astigmatism well.

[0105] from Fig.18 It can be seen that the f~tan(θ) distortion of the optical lens 400 is controlled within 0~2.5%, indicating that the distortion of the optical lens 400 is well corrected.

[0106] from Fig.19 It can be seen that the offset of the axial aberration is controlled within ±0.06 mm, indicating that the optical lens 400 can correct the axial aberration well.

[0107] from Fig. 20 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3μm~5μm, indicating that the optical lens 400 can extremely well correct the chromatic aberration of each field of view.

[0108] Example 5 See also Fig.21 , shown is a schematic diagram of the structure of the optical lens 500 provided in Example 5 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 a concave surface; the object-side surface S7 of the fourth lens L4 is a concave surface; the image-side surface S8 of the fourth lens L4 is a convex surface; the object-side surface S9 of the fifth lens L5 is a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0109] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0110] Table 5-1 The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0111] 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 shown.

[0112] from Fig. 22 It can be seen 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.

[0113] from Fig.23It can be seen that the f~tan(θ) distortion of the optical lens 500 is controlled within -0.5%~2%, indicating that the distortion of the optical lens 500 is well corrected.

[0114] from Fig.24 It can be seen that the offset of the axial aberration is controlled within -0.05mm~0.08mm, which means that the optical lens 500 can correct the axial aberration well.

[0115] from Fig.25 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5μm, indicating that the optical lens 500 can extremely well correct the chromatic aberration of each field of view.

[0116] Please refer to Table 6, 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 half field of view angle, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0117] Table 6 In summary, the optical lens provided by the present invention has at least the following advantages: The optical lens provided by the present invention has a small size through a specific surface shape setting and a reasonable distribution of optical focal length; it can also achieve a large image height of the lens, and can be matched with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration of the image; the lens has a large aperture, and high-definition imaging can be achieved even in a dim environment; it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has a high pixel, and the imaging quality of the optical lens is improved.

[0118] 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.

[0119] 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 surface is convex and whose image side surface is concave; A second lens with negative optical power, whose object side surface is convex and whose image side surface is concave; A third lens with negative optical power; A fourth lens with negative optical power; A fifth lens with negative optical power, whose image side surface is concave near the optical axis; A sixth lens with positive optical power, whose object side surface is convex near the optical axis and whose image side surface is convex; A seventh lens with negative optical power, whose object side surface is concave and whose image side surface is concave near the optical axis; Wherein, the total optical length TTL of the optical lens satisfies: 6.5mm < TTL < 6.9mm; The total optical length TTL of the optical lens, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 12.8mm < TTL×(IH / f) < 13.5mm.

2. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 4.1mm < TTL / Fno < 4.5mm.

3. The optical lens according to claim 1, characterized in that: The sagittal height SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens, the sagittal height SAGX62 corresponding to the maximum clear aperture semi-diameter at the image side end of the sixth lens and the spacing AT67 between the sixth lens and the seventh lens on the optical axis satisfy: -0.8 < (SAGX71 - SAGX62) / AT67 < -0.

3.

4. The optical lens according to claim 1, characterized in that: The total optical length TTL 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: 1.2 < (TTL×tan(FOV / 2)) / (IH / 2) < 1.

3.

5. The optical lens according to claim 1, characterized in that: The clear aperture semi-diameter CSD11 at the object side end of the first lens, the clear aperture semi-diameter CSD61 at the object side end of the sixth lens and the clear aperture semi-diameter CSD72 at the image side end of the seventh lens satisfy: 0.22 < CSD11 / (CSD61 + CSD72) < 0.

23.

6. The optical lens according to claim 1, characterized in that: The central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, the central thickness CT4 of the fourth lens on the optical axis and the central thickness CT5 of the fifth lens on the optical axis satisfy: 0.35mm < (CT2 + CT3 + CT4 + CT5) / 4 < 0.55mm.

7. The optical lens according to claim 1, characterized in that: The focal length f6 of the sixth lens, the focal length f7 of the seventh lens and the focal length f5 of the fifth lens satisfy: 0.02 < (f6 + f7) / f5 < 0.

07.

8. The optical lens according to claim 1, characterized in that: The central thickness CT6 of the sixth lens and the edge thickness ET6 of the sixth lens satisfy: 1.8 < CT6 / ET6 < 3.

5.

9. The optical lens according to claim 1, characterized in that: The sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 2 < ∑CT / ∑AT < 3.

10. 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: -30 < f4 / f < -9; the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -2.1 < f5 / f < -1.3.

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