Optical lens

Abstract

The present invention provides an optical lens having seven lenses, which includes, in order from the object side to the imaging surface along the optical axis: a first lens having positive focal power, with a convex object-side surface and a concave image-side surface; a second lens having negative focal power, with a convex object-side surface at the near optical axis and a concave image-side surface; a third lens having positive focal power, with a convex object-side surface and a concave image-side surface at the near optical axis; a fourth lens having positive focal power, with a convex object-side surface at the near optical axis and a concave image-side surface at the near optical axis; a fifth lens having negative focal power, with a concave object-side surface and a concave image-side surface at the near optical axis; a sixth lens having positive focal power, with a convex object-side surface at the near optical axis and a concave image-side surface at the near optical axis; and a seventh lens having negative focal power, with a convex object-side surface and a concave image-side surface at the near optical axis. The optical lens provided by the present invention has one or more advantages, including a short total length, a large aperture, and small distortion.

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] In recent years, consumers' expectations for smartphone photography have continued to rise. They not only demand thinner and lighter lenses, but also demand clear, bright images in a variety of environments. However, existing smartphone lenses on the market are either long, hindering thinness, or have small apertures, resulting in insufficient brightness and blurry images in dim environments. Consequently, the mainstream trend in consumer electronics is towards ultra-thinness and the ability to capture high-definition images in complex environments. This trend places higher demands on the optical lenses used in these products. 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 technical solution adopted in the present invention is:

[0005] An optical lens, comprising seven lenses, including the following elements in order from the object side to the imaging surface along the optical axis:

[0006] The first lens has positive refractive power, its object-side surface is convex and its image-side surface is concave;

[0007] a second lens element having negative optical power, whose object-side surface is convex near the optical axis and whose image-side surface is concave;

[0008] The third lens element has positive refractive power, its object side surface is convex, and its image side surface is concave near the optical axis;

[0009] a fourth lens element having positive refractive power, whose object-side surface is convex near the optical axis and whose image-side surface is concave near the optical axis;

[0010] a fifth lens element having negative optical power, the object-side surface of which is concave near the optical axis, and the image-side surface of which is concave near the optical axis;

[0011] a sixth lens element having positive refractive power, whose object-side surface is convex near the optical axis and whose image-side surface is concave near the optical axis;

[0012] The seventh lens element has a negative optical power, the object-side surface of which is convex near the optical axis, and the image-side surface of which is concave near the optical axis;

[0013] The object-side curvature radius R9 of the fifth lens and the image-side curvature radius R10 of the fifth lens satisfy the relationship: -1<(R9+R10) / (R9-R10)<0.

[0014] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.25 < TTL / f < 1.35; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.65 < TTL / IH < 0.69.

[0015] Further preferably, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 57° < FOV / Fno < 60°; the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.1.

[0016] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 1.85 < IH / f < 2.05; the true image height IH corresponding to the maximum field angle of the optical lens and the back focal length BFL of the optical lens satisfy: 7.7 < IH / BFL < 8.8.

[0017] Further preferably, the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the total optical length TTL of the optical lens satisfy: 0.55 < ΣCT / TTL < 0.59; the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 0.71 < ΣCT / f < 0.78; the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: -0.92 < (R9 + R10) / (R9 - R10) < -0.13.

[0018] Further preferably, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 1.9 < f1 / f < 2.7; the curvature radius R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.49 < R1 / f < 0.56; the curvature radius R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.74 < R2 / f < 1.04.

[0019] Further preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.8 < f2 / f < -2.1; the curvature radius R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.6 < R3 / f < 0.96; the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.43 < R4 / f < 0.57.

[0020] Further preferably, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.3 < f5 / f < -1; the object-side curvature radius R9 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.68 < R9 / f < -0.74; the image-side curvature radius R10 of the fifth lens and the effective focal length f of the optical lens satisfy: 3.51 < R10 / f < 16.09.

[0021] Further preferably, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.6 < f7 / f < -1.1; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.49 < R13 / f < 0.92; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.32 < R14 / f < 0.41.

[0022] Further preferably, the sagittal height Sag9 of the object-side clear aperture of the fifth lens and the object-side clear aperture diameter d9 of the fifth lens satisfy: -0.25 < Sag9 / d9 < -0.19; the sagittal height Sag10 of the image-side clear aperture of the fifth lens and the image-side clear aperture diameter d10 of the fifth lens satisfy: -0.21 < Sag10 / d10 < -0.11.

[0023] The optical lens provided by the present invention uses seven lenses with specific optical powers. Through specific surface shape combinations and reasonable optical power distributions, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, making the lens have one or more advantages such as a short overall length, a large aperture, and a small distortion. Description of the Drawings

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, where:

[0025] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is an F-Tan(Theta) distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0030] Figure 6 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0031] Figure 7 Graph showing the field curvature of the optical lens in Example 2 of the present invention.

[0032] Figure 8 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 2 of the present invention.

[0033] Figure 9 2 is an axial aberration curve diagram of the optical lens in Example 2 of the present invention.

[0034] Figure 10 Graph showing vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0035] Figure 11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0036] Figure 12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0037] Figure 13 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0038] Figure 14 4 is an axial aberration curve diagram of the optical lens in Example 3 of the present invention.

[0039] Figure 15 Graph showing vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0040] Figure 16 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0041] Figure 17 4 is a field curvature curve diagram of the optical lens in Example 4 of the present invention.

[0042] Figure 18 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 4 of the present invention.

[0043] Figure 19 4 is an axial aberration curve diagram of the optical lens in Example 4 of the present invention.

[0044] Figure 20 Graph showing vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0045] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0046] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely descriptions of 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.

[0047] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of the present invention.

[0048] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0049] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0050] 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 preclude 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 list of 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.

[0051] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0052] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this 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.

[0053] An optical lens provided by an embodiment of the present invention includes seven lenses, which are, along the optical axis, from the object side to the imaging surface, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0054] In some embodiments, the first lens may have positive optical power, the object-side surface thereof may be convex, and the image-side surface thereof may be concave. The second lens may have negative optical power, the object-side surface thereof may be convex at the near optical axis, and the image-side surface thereof may be concave. The third lens may have positive optical power, the object-side surface thereof may be convex, and the image-side surface thereof may be concave at the near optical axis. The fourth lens may have positive optical power, the object-side surface thereof may be convex at the near optical axis, and the image-side surface thereof may be concave at the near optical axis. The fifth lens may have negative optical power, the object-side surface thereof may be concave at the near optical axis, and the image-side surface thereof may be concave at the near optical axis. The sixth lens may have positive optical power, the object-side surface thereof may be convex at the near optical axis, and the image-side surface thereof may be concave at the near optical axis. The seventh lens may have negative optical power, the object-side surface thereof may be convex at the near optical axis, and the image-side surface thereof may be concave at the near optical axis.

[0055] In some embodiments, the optical lens may further include an aperture, which may be located between the object side and the first lens. It is understood that the aperture is used to limit the amount of light entering to change the brightness of the image.

[0056] In some embodiments, the optical lens may further include a filter, which 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.

[0057] In some embodiments, the radius of curvature R9 of the object-side surface of the fifth lens element and the radius of curvature R10 of the image-side surface of the fifth lens element satisfy the following relationship: -1 < (R9 + R10) / (R9 - R10) < 0. By meeting this range and appropriately defining the shapes of the object-side and image-side surfaces of the fifth lens element, the fifth lens element can be controlled to have an appropriate surface shape, effectively correcting aberrations of the optical lens. More specifically, the following relationship: -0.92 < (R9 + R10) / (R9 - R10) < -0.13.

[0058] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.25 < TTL / f < 1.35; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.65 < TTL / IH < 0.69. Satisfying the above ranges can effectively limit the length of the lens, which is beneficial to reducing the volume of the optical lens. At the same time, it ensures that when the lens is used for wide-angle shooting, it still maintains a compact structure and has the characteristic of a short total length. More specifically: 1.28 < TTL / f < 1.34.

[0059] In some embodiments, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 57° < FOV / Fno < 60°; the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.1. Satisfying the above ranges, reasonably limiting the ratio of the maximum field angle to the aperture is beneficial to ensuring a large field of view while increasing the light input, and thus achieving high-pixel imaging. At the same time, reasonably limiting the ratio of the image height to the entrance pupil diameter is beneficial to balancing the imaging quality and the volume of the lens. More specifically: 57.32° < FOV / Fno < 59.34°; 2.84 < IH / EPD < 3.03.

[0060] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 1.85 < IH / f < 2.05; the true image height IH corresponding to the maximum field angle of the optical lens and the back focal length BFL of the optical lens satisfy: 7.7 < IH / BFL < 8.8. Satisfying the above ranges is beneficial to controlling the field angle within a suitable range. At the same time, the lens has the characteristic of miniaturization. More specifically: 1.89 < IH / f < 2.02; 7.77 < IH / BFL < 8.77.

[0061] In some embodiments, the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the total optical length TTL of the optical lens satisfy: 0.55 < ΣCT / TTL < 0.59; the sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 0.71 < ΣCT / f < 0.78. Satisfying the above ranges, controlling the total optical length of the optical lens and the sum of the central thicknesses of each lens within a reasonable range can facilitate the structural design and processing, and further improve the imaging quality. At the same time, controlling the effective focal length of the optical lens and the sum of the central thicknesses of each lens within a reasonable range makes the lens more compact, which is beneficial to realizing the miniaturization of the lens.

[0062] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 1.9 < f1 / f < 2.7; the radius of curvature R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.49 < R1 / f < 0.56; the radius of curvature R2 of the image side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.74 < R2 / f < 1.04. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the first lens and its surface shape, it is beneficial to diverge light and improve the brightness of the edge field of view. More specifically: 1.94 < f1 / f < 2.7.

[0063] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.8 < f2 / f < -2.1; the radius of curvature R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.6 < R3 / f < 0.96; the radius of curvature R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.43 < R4 / f < 0.57. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the second lens and its surface shape, it is beneficial to obtain a wider field of view without changing the physical size of the lens. More specifically: -3.74 < f2 / f < -2.13.

[0064] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.3 < f5 / f < -1; the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: -2.68 < R9 / f < -0.74; 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: 3.51 < R10 / f < 16.09. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the fifth lens and its surface shape, it can effectively balance the lens aberration and improve the imaging quality. More specifically: -2.25 < f5 / f < -1.03.

[0065] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.6 < f7 / f < -1.1; the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 0.49 < R13 / f < 0.92; 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: 0.32 < R14 / f < 0.41. Satisfying the above ranges, by reasonably defining the proportion of the optical power of the seventh lens and its surface shape, it is beneficial to reduce the aberration and distortion. More specifically: -2.53 < f7 / f < -1.11.

[0066] In some embodiments, the sagittal height Sag9 of the clear aperture on the object side of the fifth lens and the clear aperture diameter d9 of the object side of the fifth lens satisfy: -0.25 < Sag9 / d9 < -0.19; the sagittal height Sag10 of the clear aperture on the image side of the fifth lens and the clear aperture diameter d10 of the image side of the fifth lens satisfy: -0.21 < Sag10 / d10 < -0.11. Meeting the above ranges helps to control the light path and highlight the detailed information of the central field of the optical lens.

[0067] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.1 < f3 / f < 1.7. Meeting the above range reasonably limits the proportion of the optical power of the third lens, which is beneficial to balancing spherical aberration, resulting in smaller axial aberration and good imaging quality. More specifically: 1.12 < f3 / f < 1.7.

[0068] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 3.1 < f4 / f < 6.6. Meeting the above range reasonably limits the proportion of the optical power of the fourth lens, which is beneficial to balancing lens aberration and improving imaging quality. More specifically: 3.15 < f4 / f < 6.52.

[0069] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1 < f6 / f < 1.7; the radius of curvature R11 of the object side of the sixth lens and the effective focal length f of the optical lens satisfy: 0.39 < R11 / f < 0.48; the radius of curvature R12 of the image side of the sixth lens and the effective focal length f of the optical lens satisfy: 0.75 < R12 / f < 0.91. Meeting the above ranges can improve the imaging quality of the optical system and make the image more real and natural by reasonably limiting the proportion of the optical power of the sixth lens and its surface shape. More specifically: 1.02 < f6 / f < 1.63.

[0070] In some embodiments, the radius of curvature R7 of the object side of the fourth lens and the radius of curvature R8 of the image side of the fourth lens satisfy: -1.39 < (R7 + R8) / (R7 - R8) < -1.13. Meeting the above range can control the fourth lens to have an appropriate surface shape by reasonably limiting the shapes of the object side and the image side of the fourth lens, effectively improving field curvature and aberration and enhancing imaging quality.

[0071] In some embodiments, the optical lens satisfies the following conditional expressions: 4 mm < f < 5 mm; 85° < FOV < 90°; 2.8 mm < EPD < 3.1 mm; 5.5 mm < TTL < 6 mm; 1.4 < Fno < 1.6; 8.5 mm < IH < 8.7 mm; 38° < CRA < 40°; 0.95 mm < BFL < 1.15 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the 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, CRA represents the chief ray angle of incidence at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as a short overall length, a large aperture, and low distortion. More specifically: 4.27 mm < f < 4.54 mm; 85.9° < FOV < 89.1°; 2.84 mm < EPD < 3.03 mm; 5.66 mm < TTL < 5.88 mm; 1.49 < Fno < 1.51; 8.58 mm < IH < 8.64 mm; 38.13° < CRA < 39.64°; 0.97 mm < BFL < 1.11 mm.

[0072] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt a fully plastic lens structure, which can make the structure of the lens relatively compact, and can better achieve the balance of miniaturization and high image quality of the lens, and reduce costs.

[0073] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving the miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention all adopt aspherical lenses.

[0074] In various embodiments of the present invention, when the lens adopts an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0075] ;

[0076] Where z is the distance between the surface and the vertex 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, and B, C, D, E, F, G, H, I, and J are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order, eighteenth-order, and twentieth-order surface coefficients, respectively.

[0077] The present invention is further illustrated below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens vary; for details, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the present invention is not limited thereto. Any other changes, substitutions, combinations, or simplifications that do not deviate from the novelties of the present invention shall be considered equivalent replacements and are included within the scope of protection of the present invention.

[0078] Example 1

[0079] See also Figure 1 , shown is a schematic structural diagram of the optical lens 100 provided in Example 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging surface, 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.

[0080] The first lens L1 has positive refractive power, its object-side surface S1 is convex, and its image-side surface S2 is concave;

[0081] The second lens L2 has negative refractive power, its object-side surface S3 is convex at the near optical axis, and its image-side surface S4 is concave;

[0082] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is concave;

[0083] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex at the near optical axis, and its image-side surface S8 is concave at the near optical axis;

[0084] The fifth lens L5 has negative refractive power, its object-side surface S9 is concave, and its image-side surface S10 is concave near the optical axis;

[0085] The sixth lens L6 has positive refractive power, an object-side surface S11 of which is convex at the near optical axis, and an image-side surface S12 of which is concave at the near optical axis;

[0086] The seventh lens L7 has negative refractive power, its object-side surface S13 is convex near the optical axis, and its image-side surface S14 is concave near the optical axis;

[0087] The object-side surface S15 and the image-side surface S16 of the filter G1 are both flat surfaces;

[0088] The imaging surface S17 is a plane.

[0089] 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.

[0090] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0091] Table 1-1

[0092]

[0093] 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

[0095]

[0096] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are shown as follows: Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 shown.

[0097] Figure 2 The following is a graph of field curvature for Example 1, showing the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: degrees). As can be seen from the graph, the field curvature of the meridional and sagittal image planes is controlled within ±0.08 mm, indicating that the optical lens 100 is capable of effectively correcting field curvature.

[0098] Figure 3 The following graph shows the F-Tan (Theta) distortion curve for Example 1, which represents the F-Tan (Theta) distortion at different image heights on the imaging plane. The horizontal axis represents the F-Tan (Theta) distortion value (unit: %), and the vertical axis represents the half field of view angle (unit: °). As can be seen from the graph, the F-Tan (Theta) distortion of the optical lens 100 is controlled within 0% to 2%, indicating that the distortion of the optical lens 100 is well corrected.

[0099] Figure 4The axial aberration curve of Example 1 is shown, which represents the aberration of each wavelength on the optical axis at the imaging plane, with the horizontal axis representing the axial aberration value (unit: mm) and the vertical axis representing the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within -0.04mm to 0.03mm, indicating that the optical lens 100 is able to correct the axial aberration well.

[0100] Figure 5 A vertical chromatic aberration curve for Example 1 is shown, showing the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging plane. 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 normalized field of view angle. As can be seen from the graph, the vertical chromatic aberration for the longest and shortest wavelengths is controlled within a range of -1.5 μm to 1 μm, demonstrating that the optical lens 100 is capable of excellently correcting chromatic aberration in the peripheral field of view and the secondary spectrum across the entire image plane.

[0101] Example 2

[0102] See also Figure 6 , shown is a schematic structural diagram 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.

[0103] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0104] Table 2-1

[0105]

[0106] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0107] Table 2-2

[0108]

[0109] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 200 are shown as follows: Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 shown.

[0110] 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 -0.08mm~0.06mm, indicating that the optical lens 200 can correct the field curvature well.

[0111] from Figure 8It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens is controlled within -0.5%~1.8%, indicating that the distortion of the optical lens 200 is well corrected.

[0112] from Figure 9 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0113] from Figure 10 It can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1μm~1.5μm, indicating that the optical lens 200 can excellently correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0114] Example 3

[0115] See also Figure 11 , 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 has the following main differences: the image-side surface S6 of the third lens L3 is concave at the near optical axis; the object-side surface S9 of the fifth lens L5 is concave at the near optical axis; 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 300 in Example 3 are shown in Table 3-1.

[0117] Table 3-1

[0118]

[0119] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0120] Table 3-2

[0121]

[0122] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown as follows: Figure 12 、 Figure 13 、 Figure 14 、 Figure 15 shown.

[0123] from Figure 12 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12mm~0.04mm, indicating that the optical lens 300 can correct the field curvature well.

[0124] from Figure 13It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens is controlled within 0%~1.8%, indicating that the distortion of the optical lens 300 is well corrected.

[0125] from Figure 14 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0126] from Figure 15 It can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1μm~1.5μm, indicating that the optical lens 300 can excellently correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0127] Example 4

[0128] See also Figure 16 , shown is a schematic structural diagram of the optical lens 400 provided in Example 4 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 concave at the near optical axis; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0129] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0130] Table 4-1

[0131]

[0132] The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0133] Table 4-2

[0134]

[0135] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 400 are shown as follows: Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 shown.

[0136] from Figure 17 It can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08mm~0.07mm, indicating that the optical lens 400 can correct the field curvature well.

[0137] from Figure 18It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens is controlled within -0.5%~2%, indicating that the distortion of the optical lens 400 is well corrected.

[0138] from Figure 19 It can be seen from the figure 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.

[0139] from Figure 20 It can be seen that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1.5μm~1μm, indicating that the optical lens 400 can extremely well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0140] Please refer to Table 5-1 and Table 5-2, which show the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, chief ray incidence angle CRA at maximum image height, real image height IH corresponding to maximum field of view angle, maximum field of view angle FOV, entrance pupil diameter EPD, back focal length BFL of the optical lens, and the numerical value corresponding to each conditional expression in each embodiment.

[0141] Table 5-1

[0142]

[0143] Table 5-2

[0144]

[0145] In summary, the optical lens provided by the present invention uses seven lenses with specific optical powers. Through the combination of specific surface shapes and reasonable optical power distribution, it is possible to improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as a short total length, a large aperture, and small distortion.

[0146] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0147] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: It successively includes from the object side to the imaging plane 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 near the optical axis and whose image side is concave; A third lens with positive optical power, whose object side is convex and whose image side is concave near the optical axis; A fourth 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 fifth lens with negative optical power, whose object side is concave near the optical axis and whose image side is concave near the optical axis; 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 convex near the optical axis and whose image side is concave near the optical axis; Wherein, the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: -1 < (R9 + R10) / (R9 - R10) < 0; The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.25 < TTL / f < 1.

35.

2. The optical lens according to claim 1, wherein: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.28 < TTL / f < 1.34; The overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.65 < TTL / IH < 0.

69.

3. The optical lens according to claim 1, wherein: The maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 57° < FOV / Fno < 60°; The true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 2.8 < IH / EPD < 3.

1.

4. The optical lens according to claim 1, wherein: The true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 1.85 < IH / f < 2.05; The true image height IH corresponding to the maximum field angle of the optical lens and the back focal length BFL of the optical lens satisfy: 7.7 < IH / BFL < 8.

8.

5. The optical lens according to claim 1, wherein: The sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the overall optical length TTL of the optical lens satisfy: 0.55 < ΣCT / TTL < 0.59; The sum ΣCT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the effective focal length f of the optical lens satisfy: 0.71 < ΣCT / f < 0.78; The radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: -0.92 < (R9 + R10) / (R9 - R10) < -0.

13.

6. The optical lens according to claim 1, wherein: The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 1.9 < f1 / f < 2.7; the object-side curvature radius R1 of the first lens and the effective focal length f of the optical lens satisfy: 0.49 < R1 / f < 0.56; the image-side curvature radius R2 of the first lens and the effective focal length f of the optical lens satisfy: 0.74 < R2 / f < 1.

04.

7. The optical lens according to claim 1, wherein: The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.8 < f2 / f < -2.1; the object-side curvature radius R3 of the second lens and the effective focal length f of the optical lens satisfy: 0.6 < R3 / f < 0.96; the image-side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: 0.43 < R4 / f < 0.

57.

8. The optical lens according to claim 1, wherein: The focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.3 < f5 / f < -1; the object-side curvature radius R9 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.68 < R9 / f < -0.74; the image-side curvature radius R10 of the fifth lens and the effective focal length f of the optical lens satisfy: 3.51 < R10 / f < 16.

09.

9. The optical lens according to claim 1, wherein: The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -2.6 < f7 / f < -1.1; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.49 < R13 / f < 0.92; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: 0.32 < R14 / f < 0.

41.

10. The optical lens according to claim 1, wherein: The object-side clear aperture sagittal height Sag9 of the fifth lens and the object-side clear aperture d9 of the fifth lens satisfy: -0.25 < Sag9 / d9 < -0.19; the image-side clear aperture sagittal height Sag10 of the fifth lens and the image-side clear aperture d10 of the fifth lens satisfy: -0.21 < Sag10 / d10 < -0.11.

Images