Optical lens

Abstract

The present invention provides an optical lens which sequentially includes, along the optical axis from the object side to the imaging surface: 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 positive optical power, whose image side is convex; a fourth lens with positive optical power, whose object side is convex near the optical axis; a fifth lens with positive optical power, whose object side is concave and whose image side is convex; a sixth lens with positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; a seventh lens with negative optical power, whose object side is concave and whose image side is concave near the optical axis. The optical lens provided by the present invention has one or more advantages such as a large target surface, a large aperture, miniaturization, and high imaging quality.

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 rapid development of the performance and technology of electronic products, people have higher and higher requirements for the shooting function of portable electronic products. At present, the main camera of mainstream mobile phone lenses uses a target surface smaller than 1 / 1.5 inches. Due to the constraints of pixels and pixel points, it is impossible to meet the requirements of high pixels and large pixel points at the same time. Insufficient photosensitivity when taking pictures in a dark environment will bring a lot of noise to the image quality, resulting in a decline in image quality and unclear imaging. Summary of the Invention

[0003] In view of the above problems, the purpose of the present invention is to provide an optical lens, which has one or more advantages such as a large target surface, a large aperture, miniaturization, and high imaging quality.

[0004] The technical solution adopted by the present invention is as follows:

[0005] An optical lens is composed of seven lenses, and sequentially includes from the object side to the imaging surface along the optical axis:

[0006] A first lens with positive optical power, whose object side is convex and whose image side is concave;

[0007] A second lens with negative optical power, whose object side is convex and whose image side is concave;

[0008] A third lens with positive optical power, whose image side is convex;

[0009] A fourth lens with positive optical power, whose object side is convex near the optical axis;

[0010] A fifth lens with positive optical power, whose object side is concave and whose image side is convex;

[0011] A sixth lens with positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis;

[0012] A seventh lens with negative optical power, whose object side is concave and whose image side is concave near the optical axis;

[0013] Wherein, the total optical length TTL of the optical lens, the true image height ih corresponding to the maximum half field of view angle of the optical lens, and the effective focal length f of the optical lens satisfy: 7.4mm < TTL × (ih / f) < 8.4mm.

[0014] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 < TTL / f < 1.4.

[0015] 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 distances between any two adjacent lenses among the first lens to the seventh lens on the optical axis satisfy: 1.4 < ∑CT / ∑AT < 2.2.

[0016] More preferably, the total optical length TTL of the optical lens and the sum ∑CT15 of the central thicknesses of the first lens to the fifth lens on the optical axis respectively satisfy: 2.3 < TTL / ∑CT15 < 2.8.

[0017] More preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 < f1 / f < 1.35.

[0018] More preferably, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 < f1 / f2 < -0.3.

[0019] More preferably, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the clear aperture semi-diameter CSD71 at the object side end of the seventh lens satisfy: 0.5 < CSD11 / CSD71 < 0.7.

[0020] More preferably, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the true image height ih corresponding to the maximum half field angle of the optical lens satisfy: 0.3 < CSD11 / ih < 0.4.

[0021] More preferably, the sagitta SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens and the central thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 < SAGX71 / CT7 < -2.2.

[0022] More preferably, the effective focal length f of the optical lens, the central thickness CT6 of the sixth lens on the optical axis, the distance CT67 between the sixth lens and the seventh lens on the optical axis, and the central thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 < f / (CT6 + CT67 + CT7) < 2.9.

[0023] More preferably, the central thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 < CT7 / ET7 < 0.7.

[0024] Compared with the prior art, the optical lens provided by the present invention has a small volume through specific surface shape settings and reasonable optical power distribution; it can also achieve the large target surface characteristic of the lens, be able to cooperate with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration degree of the image; enable the lens to have a large aperture, and can achieve high-definition imaging even in a dim environment; and can also reasonably correct the overall aberration of the optical lens, make the optical lens have high pixels, and improve the imaging quality of the optical lens. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0027] Figure 2 is a graph of F-Tan(Theta) distortion of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 is a graph of field curvature of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 is a graph of lateral chromatic aberration of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0031] Figure 6 is a graph of F-Tan(Theta) distortion of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 7 is a graph of field curvature of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 8 is a graph of lateral chromatic aberration of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 9 is a schematic structural diagram of the optical lens in Embodiment 3 of the present invention.

[0035] Figure 10 is a graph of F-Tan(Theta) distortion of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 11 is a graph of field curvature of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 12 is a graph of lateral chromatic aberration of the optical lens in Embodiment 3 of the present invention.

[0038] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0039] For a better understanding of the present application, more detailed descriptions of various aspects of the present application will be made 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 do not 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.

[0040] It should be noted that in this specification, the expressions such as 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 teachings of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0041] In the drawings, for ease of illustration, the thickness, dimensions, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are for illustrative purposes only and are not drawn to an exact scale.

[0042] In this document, 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 being photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

[0043] It should also be understood that the terms "comprises", "comprising", "has", "including", and / or "including having", 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 an expression such as "at least one of..." appears after a list of listed features, it modifies the entire list of listed features rather than an individual element in the list. In addition, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". And the term "exemplary" is intended to refer to an example or illustration.

[0044] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in common dictionaries) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0045] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments may be combined with each other. The following will describe this application in detail with reference to the drawings and in conjunction with the embodiments.

[0046] The optical lens provided by the embodiment of the present invention is composed of seven lenses, which are, 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.

[0047] In some embodiments, the first lens may have a positive optical power, its object side surface is convex, and its image side surface is concave. The second lens may have a negative optical power, its object side surface is convex, and its image side surface is concave. The third lens may have a positive optical power, its object side surface may be concave or convex, and its image side surface is convex. The fourth lens may have a positive optical power, its object side surface is convex near the optical axis, and its image side surface may be concave or convex. The fifth lens may have a positive optical power, its object side surface is concave, and its image side surface is convex. The sixth lens may have a positive optical power, its object side surface is convex near the optical axis, and its image side surface is concave near the optical axis. The seventh lens may have a negative optical power, its object side surface is concave, and its image side surface is concave near the optical axis. <<

[0048] 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.

[0049] 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.

[0050] In some embodiments, the total optical length TTL of the optical lens, the true image height ih corresponding to the maximum half field of view angle of the optical lens, and the effective focal length f of the optical lens satisfy: 7.4 mm < TTL × (ih / f) < 8.4 mm. When the above conditions are met, by restricting the total length of the optical lens, it is ensured that the optical lens meets the requirements of a large imaging surface and has sufficiently good imaging quality; at the same time, the imaging lens also meets the requirements of high pixels and large pixel points, making the pixel size larger under the same number of pixels, reducing noise in a dark environment, and retaining more details in the dark part, thereby obtaining high imaging quality.

[0051] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 < TTL / f < 1.4. When the above conditions are met, the total length of the optical lens and the distribution of the optical focal length can be reasonably controlled, the total length of the optical lens can be shortened, the sensitivity of the optical lens can be reduced, and then it can be matched with the image sensor to improve the imaging quality of the optical lens.

[0052] 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 of the first lens to the seventh lens on the optical axis satisfy: 1.4 < ∑CT / ∑AT < 2.2. When the above conditions are met, by reasonably controlling the sum of the central thicknesses of each lens of the optical lens, the distortion range of the optical lens can be reasonably controlled, so that the optical lens has a small distortion.

[0053] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT15 of the central thicknesses of the first lens to the fifth lens on the optical axis respectively satisfy: 2.3 < TTL / ∑CT15 < 2.8. When the above conditions are met, the proportion of the sum of the central thicknesses of the first five lenses of the optical lens in the total optical length can be reasonably restricted, which is beneficial to improving the structural compactness of the optical lens, realizing miniaturized design, and preventing the length ratio of the first five lenses in the optical lens from being too large, so as to help prevent large deflection of the incident light when entering the sixth lens, and then contribute to suppressing aberration and improving the imaging quality of the optical lens.

[0054] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 < f1 / f < 1.35. When the above conditions are met, by restricting the ratio of the focal length of the first lens to the focal length of the optical lens, it is beneficial to reasonably configure the refractive power of the first lens to support the large field of view angle and large aperture characteristics of the optical lens, is beneficial to converging the incident light entering the optical lens from the object side, reducing the deflection angle, is beneficial to the aberration balance of the optical lens, and improves the imaging quality of the optical lens.

[0055] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 < f1 / f2 < -0.3. When the above conditions are met, the effective focal lengths of the first lens and the second lens can be reasonably configured to effectively balance the chromatic aberration of the optical lens and reduce the performance sensitivity of the optical lens, making the performance of the optical lens more stable.

[0056] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the clear aperture semi-diameter CSD71 at the object side end of the seventh lens satisfy: 0.5 < CSD11 / CSD71 < 0.7. When the above conditions are met, the clear aperture semi-diameters of the object side surfaces of the first lens and the seventh lens can be reasonably configured, which is beneficial to restricting the size of the first lens, enabling the optical lens to achieve a small head design, and further improving the screen-to-body ratio of the electronic device equipped with the optical lens; and it can also provide a relatively large entrance pupil for the optical lens to expand the aperture, so that the optical lens has sufficient light transmission, thereby improving the imaging quality of the optical lens.

[0057] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the true image height ih corresponding to the maximum half field of view angle of the optical lens satisfy: 0.3 < CSD11 / ih < 0.4. When the above conditions are met, it can ensure that the optical lens has a relatively large clear aperture and a relatively large imaging surface, and can achieve a reasonable balance between the large light transmission and the large imaging surface of the optical lens, which helps to improve the imaging quality.

[0058] In some embodiments, the sagittal height SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens and the central thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 < SAGX71 / CT7 < -2.2. When the above conditions are met, the incident angle of the chief ray on the object side surface of the seventh lens can be effectively reduced, and the matching degree between the optical lens and the photosensitive chip can be improved.

[0059] In some embodiments, the effective focal length f of the optical lens, the central thickness CT6 of the sixth lens on the optical axis, the spacing CT67 between the sixth lens and the seventh lens on the optical axis, and the central thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 < f / (CT6 + CT67 + CT7) < 2.9. When the above conditions are met, by reasonably setting the central thicknesses and the spacing of the sixth lens and the seventh lens, the astigmatism of the optical lens can be effectively balanced, and the contribution of the distortion of the sixth lens and the seventh lens can be restricted, improving the imaging quality of the optical lens, and helping to shorten the total length of the optical lens.

[0060] In some embodiments, the central thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 < CT7 / ET7 < 0.7. When the above conditions are met, the central thickness and the edge thickness of the seventh lens can be reasonably configured, so that the deflection angle of the light passing through the seventh lens is smaller, reducing the generation of stray light in the optical lens and improving the imaging quality of the optical lens; the ratio of the central thickness to the edge thickness of the seventh lens is beneficial to the injection molding and assembly of the seventh lens, improving the injection molding yield of the seventh lens and reducing the production cost of the seventh lens.

[0061] In some embodiments, the total optical length TTL of the optical lens and the true image height ih corresponding to the maximum half field of view angle of the optical lens satisfy: 0.65 < TTL / (ih×2) < 0.75. When the above conditions are met, the size of the large image plane optical lens can be constrained, which is beneficial to reducing the volume of the optical lens, saving space, and controlling the cost of the optical lens while doing so.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -3.4 < f2 / f < -2.8. When the above conditions are met, it is beneficial for the refractive power of the second lens to be properly matched in the optical lens, the surface shape design of the second lens is more simple and flexible, the aberration is reduced, and the overall aberration correction and imaging quality balance of the optical lens are simplified.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.7 < f5 / f < 3.3. When the above conditions are met, it is beneficial for the fifth lens to smoothly diffuse the light beam, laying a foundation for the optical lens to achieve large image plane imaging, thereby improving the imaging quality of the optical lens.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.85 < f[ / f < -0.6. When the above conditions are met, the deflection angle of the light in the seventh lens can be reduced, the sensitivity of the seventh lens can be lowered, and the astigmatism and distortion and other aberrations generated by the lens group in front of the seventh lens can also be reduced, thereby being beneficial to improving the imaging quality of the optical lens.

[0065] In some embodiments, the effective focal length f of the optical lens and the curvature radius R1 of the object side surface of the first lens satisfy: 0.4 < R1 / f < 0.5. When the above conditions are met, it is beneficial to maintain the astigmatism of the first lens within a reasonable range, so that the optical system has good imaging quality.

[0066] In some embodiments, the central thickness CT1 of the first lens on the optical axis and the edge thickness ET1 of the first lens satisfy: 1.8 < CT1 / ET1 < 3.6. When the above conditions are met, by controlling the central thickness and edge thickness of the first lens within a certain range, the aberration generated by the optical lens can be effectively balanced, and it is also beneficial to the field curvature adjustment in engineering production, thereby being beneficial to improving the imaging quality of the optical lens.

[0067] In some embodiments, the optical lens satisfies the conditional formula: 8.3 mm < TTL < 9 mm, 6.5 mm < f < 7.2 mm, 6 mm < ih < 6.5 mm, 1.5 < Fno < 1.7, 80° < FOV < 88°; where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, ih represents the true image height corresponding to the maximum half field of view angle of the optical lens, Fno represents the aperture value 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 the characteristics of a large target surface, a large aperture, and miniaturization.

[0068] In some embodiments, the lens material of the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected due to the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt an all-plastic lens structure, which not only enables the lens to have excellent imaging performance but also makes the structure of the lens relatively compact, and can better achieve the balance between lens miniaturization and high image quality.

[0069] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization. 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 can all adopt aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization.

[0070] In each embodiment of the present invention, when the lens adopts an aspherical lens, the surface shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0071] ;

[0072] where z is the distance between the surface and the vertex of the surface in the optical axis direction, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the conic coefficient, and B, C, D, E, F, G, H are the surface coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order respectively.

[0073] The present invention will be further described in multiple embodiments below. In each embodiment, the thickness, curvature radius, and material selection of each lens in the optical lens are somewhat different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing 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] Embodiment 1

[0075] Please refer to Figure 1 , which shows a schematic structural diagram of an optical lens 100 provided in Embodiment 1 of the present invention. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a diaphragm 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.

[0076] Among them, the first lens L1 has a positive optical power. Its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface;

[0077] The second lens L2 has a negative optical power. Its object side surface S3 is a convex surface, and its image side surface S4 is a concave surface;

[0078] The third lens L3 has a positive optical power. Its object side surface S5 is a concave surface, and its image side surface S6 is a convex surface;

[0079] The fourth lens L4 has a positive optical power. Its object side surface S7 is a convex surface near the optical axis, and its image side surface S8 is a concave surface near the optical axis;

[0080] The fifth lens L5 has a positive optical power. Its object side surface S9 is a concave surface, and its image side surface S10 is a convex surface;

[0081] The sixth lens L6 has a positive optical power. Its object side surface S11 is a convex surface near the optical axis, and its image side surface S12 is a concave surface near the optical axis;

[0082] The seventh lens L7 has a negative optical power. Its object side surface S13 is a concave surface, and its image side surface S14 is a concave surface near the optical axis;

[0083] Both the object side surface S15 and the image side surface S16 of the filter G1 are flat surfaces;

[0084] The imaging surface S17 is a flat surface.

[0085] 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 all adopt plastic aspherical lenses.

[0086] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0087] Table 1-1

[0088]

[0089] The surface type parameters of the aspherical lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0090] Table 1-2

[0091]

[0092] Figure 2 The F-Tan(Theta) distortion curve graph of the optical lens 100 in this embodiment is shown, which represents the distortion of different field angles on the imaging surface. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the distortion value is controlled within ±2%, indicating that the optical lens 100 can correct the distortion well.

[0093] Figure 3 The field curvature curve graph of the optical lens 100 in this embodiment is shown, which represents the field curvature of light rays in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 100 can correct the field curvature well.

[0094] Figure 4 The lateral chromatic aberration curve graph 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 lateral 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 lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3.5 μm, indicating that the optical lens 100 can correct the chromatic aberration well.

[0095] Embodiment 2

[0096] Please refer to Figure 5 , which shows the structural schematic diagram of the optical lens 200 provided in Embodiment 2 of the present invention. Compared with Embodiment 1, the main differences are as follows: the object side surface S5 of the third lens L3 is convex near the optical axis; the image side surface S8 of the fourth lens is convex; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0097] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0098] Table 2-1

[0099]

[0100] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0101] Table 2-2

[0102]

[0103] In this embodiment, the F-Tan (Theta) distortion curve, the field curvature curve, and the vertical axis chromatic aberration curve of the optical lens 200 are shown as follows: Figure 6 、 Figure 7 、 Figure 8 shown.

[0104] from Figure 6 It can be seen from the figure that the distortion value is controlled within ±2%, indicating that the optical lens 200 can correct the distortion well.

[0105] from Figure 7 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 200 can correct the field curvature well.

[0106] from Figure 8 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0107] Example 3

[0108] See also Figure 9 , shown is a schematic structural diagram of an optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the object-side surface S5 of the third lens L3 is a convex surface; and 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 300 in Example 3 are shown in Table 3-1.

[0110] Table 3-1

[0111]

[0112] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0113] Table 3-2

[0114]

[0115] In this embodiment, the F-Tan(Theta) distortion curve graph, field curvature curve graph, and lateral chromatic aberration curve graph of the optical lens 300 are respectively as shown in Figure 10 , Figure 11 , Figure 12 .

[0116] From Figure 10 , it can be seen that the distortion value is controlled within ±3%, indicating that the optical lens 300 can correct distortion well.

[0117] From Figure 11 , it can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 300 can correct field curvature well.

[0118] From Figure 12 , it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±3 μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0119] Please refer to Table 4 for 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 true image height ih corresponding to the maximum half field of view angle, the chief ray angle of incidence CRA at the maximum image height, the maximum field of view angle FOV, and the values corresponding to each conditional formula in each embodiment.

[0120] Table 4

[0121]

[0122] Based on the above embodiments, the optical lens provided by the present invention has at least the following advantages:

[0123] The optical lens provided by the present invention, through specific surface shape settings and reasonable optical power distribution, makes the lens have a small volume; it can also achieve the large target surface characteristic of the lens, can be matched with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration degree of the image; makes the lens have a large aperture, and can achieve high-definition imaging even in a dim environment; can also reasonably correct the overall aberration of the optical lens, making the optical lens have high pixels and improving the imaging quality of the optical lens.

[0124] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0125] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these 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 appended claims.

Claims

1. An optical lens, which is composed of 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 positive optical power, whose image side surface is convex; A fourth lens with positive optical power, whose object side surface is convex near the optical axis; A fifth lens with positive optical power, whose object side surface is concave and whose image side surface is convex; A sixth lens with positive optical power, whose object side surface is convex near the optical axis and whose image side surface is concave near the optical axis; 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, the true image height ih corresponding to the maximum half field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 7.4mm < TTL×(ih / f) < 8.4mm.

2. The optical lens according to claim 1, wherein The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 < TTL / f < 1.

4.

3. The optical lens according to claim 1, wherein 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: 1.4 < ∑CT / ∑AT < 2.

2.

4. The optical lens according to claim 1, characterized in that, The total optical length TTL of the optical lens and the sum ∑CT15 of the central thicknesses of the first lens to the fifth lens on the optical axis respectively satisfy: 2.3 < TTL / ∑CT15 < 2.

8.

5. The optical lens according to claim 1, wherein The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 < f1 / f < 1.

35.

6. The optical lens according to claim 1, wherein The focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 < f1 / f2 < -0.

3.

7. The optical lens according to claim 1, wherein The clear aperture semi-diameter CSD11 at the object side end of the first lens and the clear aperture semi-diameter CSD71 at the object side end of the seventh lens satisfy: 0.5 < CSD11 / CSD71 < 0.

7.

8. The optical lens according to claim 1, wherein, The clear aperture semi-diameter CSD11 at the object side end of the first lens and the true image height ih corresponding to the maximum half field of view angle of the optical lens satisfy: 0.3 < CSD11 / ih < 0.

4.

9. 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 and the central thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 < SAGX71 / CT7 < -2.

2.

10. The optical lens according to claim 1, wherein The effective focal length f of the optical lens, the central thickness CT6 of the sixth lens on the optical axis, the spacing CT67 between the sixth lens and the seventh lens on the optical axis and the central thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 < f / (CT6 + CT67 + CT7) < 2.

9.

11. The optical lens according to claim 1, wherein The central thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 < CT7 / ET7 < 0.7.

Images