Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power and a fifth lens with negative focal power from an object side to an imaging surface along an optical axis, the image side surface of the second lens is a convex surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex surface; the fourth lens has negative focal power; the fifth lens has positive focal power, and the object side surface of the fifth lens is a convex surface; the sixth lens has negative 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 concave surface; and the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the lens has one or more advantages of a large field angle, a large aperture, miniaturization and the like while realizing a good infrared confocal effect.

Description

Technical Field

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

[0002] With the rapid development of technology, wide-angle lenses are widely used in smart home, security, automotive, and other fields due to their advantages of large field of view and wide image format. Due to differences in application environments, consumers' performance requirements for lenses vary, but overall requirements are becoming increasingly higher. In some complex application scenarios, not only must the lens maintain focus under conditions of large temperature differences between high and low temperatures, but it must also meet shooting needs in both daytime and nighttime conditions. To this end, today's wide-angle lenses are constantly developing towards high-definition image quality, small size, and infrared confocal lenses, and the corresponding new architecture of infrared confocal lenses has become a target for development. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens having the advantages of infrared confocal and 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] a first lens having negative optical power and a concave image-side surface;

[0007] a second lens having positive refractive power and a convex image-side surface;

[0008] a third lens element having negative optical power, whose object-side surface is concave and whose image-side surface is convex;

[0009] a fourth lens element having negative optical power;

[0010] a fifth lens element having positive optical power and a convex object-side surface;

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

[0012] a seventh lens element having positive refractive power, whose object-side surface and image-side surface are convex;

[0013] The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy the following conditions: -1.8 <f1234 / f567<-0.6。

[0014] More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.5 < TTL / f < 7.5; 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: 2.7 < TTL / IH < 3.8.

[0015] More preferably, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 70° < FOV / Fno < 90°; 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: 3.2 < IH / EPD < 4.8.

[0016] More 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: 1.7 < IH / f < 2.3; the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 1.7 < BFL / f < 2.1.

[0017] More preferably, the clear aperture diameter d1 of the object side of the first lens, the true image height IH corresponding to the maximum field angle of the optical lens and the maximum field angle FOV of the optical lens satisfy: 0.19 < d1 / (IH / 2) / tan(FOV / 2) < 0.37.

[0018] More preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.3 < f1 / f < -0.9; the image side curvature radius R2 of the first lens and the effective focal length f of the optical lens satisfy: 0.8 < R2 / f < 1; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.7 < f2 / f < 2.7; the image side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -1.9 < R4 / f < -1.1.

[0019] More preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -150 < f3 / f < -9; the object side curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: -1.6 < R5 / f < -0.8; the image side curvature radius R6 of the third lens and the effective focal length f of the optical lens satisfy: -1.95 < R6 / f < -0.95.

[0020] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.9 < f6 / f < -1.4; the radius of curvature R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 13.5 < R11 / f < 40; the radius of curvature R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.9 < R12 / f < 1.8.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.3 < f7 / f < 2.1; 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: 1 < R13 / f < 2.4; 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: -5.2 < R14 / f < -1.4.

[0022] Further preferably, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: 0.7 < (R11 - R12) / (R11 + R|12) < 1; the radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: |(R13 + R14) / (R13 - R14)| < 0.7.

[0023] The optical lens provided by the present invention adopts 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 aberration, and enhance the imaging quality of the optical lens, enabling the lens to have one or more advantages such as a large field angle, a large aperture, and miniaturization while achieving a good infrared confocal effect. BRIEF 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 description of the embodiments in conjunction with the following 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 MTF curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0028] Figure 4 is a MTF curve diagram of the optical lens in Embodiment 2 of the present invention.

[0029] Figure 5Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0030] Figure 6 This is the MTF curve of the optical lens in Example 3 of the present invention.

[0031] Figure 7 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0032] Figure 8 This is the MTF curve of the optical lens in Example 4 of the present invention.

[0033] Figure 9 Schematic diagram of the structure of the optical lens in Example 5 of the present invention.

[0034] Figure 10 This is the MTF curve of the optical lens in Example 5 of the present invention.

[0035] Figure 11 Schematic diagram of the structure of the optical lens in Example 6 of the present invention.

[0036] Figure 12 This is the MTF curve of the optical lens in Example 6 of the present invention.

[0037] Figure 13 Schematic diagram of the structure of the optical lens in Example 7 of the present invention.

[0038] Figure 14 This is the MTF curve of the optical lens in Example 7 of the present invention.

[0039] Figure 15 Schematic diagram of the structure of the optical lens in Example 8 of the present invention.

[0040] Figure 16 This is the MTF curve of the optical lens in Example 8 of the present invention.

[0041] Figure 17 Schematic diagram of the structure of the optical lens in Example 9 of the present invention.

[0042] Figure 18 This is an MTF curve diagram of the optical lens in Example 9 of the present invention.

[0043] Figure 19 Schematic diagram of the structure of the optical lens in Example 10 of the present invention.

[0044] Figure 20 This is an MTF curve diagram of the optical lens in Example 10 of the present invention.

[0045] Figure 21 Schematic diagram of the structure of the optical lens in Example 11 of the present invention.

[0046] Figure 22 This is the MTF curve of the optical lens in Example 11 of the present invention.

[0047] Figure 23 Schematic diagram of the structure of the optical lens in Example 12 of the present invention.

[0048] Figure 24 This is the MTF curve of the optical lens in Example 12 of the present invention.

[0049] Figure 25 Schematic diagram of the structure of the optical lens in Example 13 of the present invention.

[0050] Figure 26 This is the MTF curve of the optical lens in Example 13 of the present invention.

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

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] It should also be understood that the terms "comprises," "including," "having," "includes," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not 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.

[0057] 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.

[0058] 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.

[0059] The optical lens provided in an embodiment of the present invention is an infrared confocal lens, which has a total of seven lenses, which are, along the optical axis from the object side to the imaging surface, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens.

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

[0061] In some embodiments, the optical lens may further include an aperture, which may be located between the fourth lens and the fifth lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image. In addition, when the aperture is located between the fourth lens and the fifth lens, the aperture can reasonably distribute the functions of the first lens to the seventh lens. For example, the first lens, the second lens, the third lens, and the fourth lens can be used to receive light to a large extent, and the fifth lens to the seventh lens can be used to correct aberrations, which is beneficial to balance the structure of the entire optical system. In addition, when the aperture is located between the fourth lens and the fifth lens, it is convenient to correct the aperture aberration.

[0062] In some embodiments, the optical lens may further include a filter and a protective glass, which may be sequentially arranged along the optical axis 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. The protective glass plays a role in protecting the optical lens, preventing the photosensitive chip from being damaged, and can improve the anti-impact and scratch-resistant capabilities of the optical lens, while having almost no impact on the imaging quality of the optical lens.

[0063] In some embodiments, the combined focal length f1234 of the first lens, the second lens, the third lens, and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens, and the seventh lens satisfy: -1.8 < f1234 / f567 < -0.6. Meeting the above range, by reasonably setting the focal lengths of the lens groups before and after the aperture, it is beneficial to balance various aberrations generated by the lens group before the aperture and improve the overall imaging quality. More specifically, -1.64 < f1234 / f567 < -0.69.

[0064] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.5 < TTL / f < 7.5. Meeting the above range can effectively limit the length of the lens, which is beneficial to the miniaturization of the optical lens. More specifically, 6.11 < TTL / f < 7.03.

[0065] In some embodiments, 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: 2.7 < TTL / IH < 3.8. Meeting the above range ensures that, with the same overall length of the lens, it has a larger image surface, can match a larger-sized imaging chip to achieve high-definition imaging, and better achieves the balance between the small overall length and the large image surface of the lens. More specifically, 2.96 < TTL / IH < 3.5.

[0066] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 70° < FOV / Fno < 90°. Meeting the above range defines that the optical lens has an appropriate field of view and aperture value, can collect light at large angles, and obtain good imaging quality. More specifically, 72° < FOV / Fno < 87.79°.

[0067] In some embodiments, the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 3.2 < IH / EPD < 4.8. Meeting the above range can increase the width of the light beam entering the optical lens, improve the brightness at the image plane of the optical lens, and avoid vignetting. More specifically, 3.54 < IH / EPD < 4.37.

[0068] In some embodiments, the true image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 1.7 < IH / f < 2.3. Meeting the above range, controlling the image height and focal length of the optical lens within a reasonable range helps the optical lens to have the characteristic of a large image plane and improve the imaging quality. More specifically, 1.88 < IH / f < 2.2.

[0069] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 1.7 < BFL / f < 2.1. Meeting the above range defines that the optical lens has an appropriate back focus, facilitates the reasonable arrangement of the positions of each lens, and reduces the processing and assembly difficulty. More specifically, 1.85 < BFL / f < 1.93.

[0070] In some embodiments, the clear aperture d1 of the object side surface of the first lens, the true image height IH corresponding to the maximum field of view of the optical lens, and the maximum field of view FOV of the optical lens satisfy: 0.19 < d1 / (IH / 2) / tan(FOV / 2) < 0.37. Meeting the above range can have a small front aperture while meeting the requirements of the optical lens having a large field of view and a large image plane.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -1.3 < f1 / f < -0.9; 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: 0.8 < R2 / f < 1. Meeting the above range, by setting the first lens to have a negative refractive power and the image side surface to be concave, it is beneficial for the first lens to accommodate light at a larger angle and collect as much light as possible to enter the rear optical system, increasing the light flux while achieving a large field of view. More specifically, -1.22 < f1 / f < -0.97; 0.83 < R2 / f < 0.96.

[0072] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 1.7 < f2 / f < 2.7; the image-side curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -1.9 < R4 / f < -1.1. Meeting the above ranges defines that the second lens has an appropriate positive optical power and a convex image side, which has the effect of converging light rays, reducing the height of peripheral light rays, and is beneficial to reducing the aperture of the rear lens. More specifically, 1.81 < f2 / f < 2.51; -1.74 < R4 / f < -1.15.

[0073] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -150 < f3 / f < -9; the object-side curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: -1.6 < R5 / f < -0.8; the image-side curvature radius R6 of the third lens and the effective focal length f of the optical lens satisfy: -1.95 < R6 / f < -0.95; the object-side curvature radius R5 of the third lens and the image-side curvature radius R6 of the third lens satisfy: -14 < (R5 + R6) / (R5 - R6) < -5. Meeting the above ranges enables the third lens to have a negative optical power and a suitable surface shape, which has the effect of diverging light rays, can disperse the central light rays and marginal light rays of each field of view, and can correct the aberration generated by the front lens. More specifically, -143.73 < f3 / f < -0.83; -1.46 < R5 / f < -0.83; -1.82 < R6 / f < -1.02.

[0074] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.9 < f6 / f < -1.4; the object-side curvature radius R11 of the sixth lens and the effective focal length f of the optical lens satisfy: 13.5 < R11 / f < 40; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: 0.9 < R12 / f < 1.8; the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: 0.7 < (R11 - R12) / (R11 + R12) < 1. Meeting the above ranges sets the sixth lens to have a negative refractive power, which is beneficial to increasing the degree of light divergence, increasing the area of light entering the imaging surface, achieving large-format imaging of the lens, and improving the imaging quality of the optical lens. More specifically, -2.65 < f6 / f < -1.54; 14.6 < R11 / f < 37.35; 0.93 < R12 / f < 1.63; 0.86 < (R11 - R12) / (R11 + R12) < 0.94.

[0075] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.3 < f7 / f < 2.1; 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: 1 < R13 / f < 2.4; 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: -5.2 < R14 / f < -1.4; the radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: |(R13 + R14) / (R13 - R14)| < 0.7. Meeting the above ranges and setting the seventh lens to have positive refractive power and a suitable surface shape is conducive to light convergence, enabling the light trend to smoothly transition to the rear, reducing the height of the light incident on the rear, avoiding light energy loss caused by too large an angle between the main light ray of the large field of view and the chip when the light reaches the imaging surface, facilitating the improvement of the illuminance of the edge field of view, and being conducive to achieving a short overall optical length. More specifically, 1.47 < f7 / f < 1.91; 1.08 < R13 / f < 2.22; -4.82 < R14 / f < -1.49; -0.6 < (R13 + R14) / (R13 - R14) < 0.2.

[0076] In some embodiments, the overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.48 < ∑CT / TTL < 0.6. Meeting the above range can effectively compress the overall length of the optical lens and is conducive to the structural design and production process of the optical lens.

[0077] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 3.24 < ΣCT / f < 4.05. Meeting the above range can effectively correct the field curvature and distortion of the optical lens and improve the imaging quality of the optical lens.

[0078] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -18 < f4 / f < -2.3. Meeting the above range limits the fourth lens to have an appropriate negative optical power, diverging the light, making the light in the edge field of view show an upward trend, being conducive to the image point on the imaging surface moving away from the optical axis, in order to facilitate achieving the effect of matching with a large chip, obtaining a larger picture, effectively eliminating aberrations, and improving the resolution ability of the optical lens. More specifically, -13.13 < f4 / f < -2.55.

[0079] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.3 < f5 / f < 2.5; 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: 0.9 < R9 / f < 2.7. Meeting the above ranges and setting the fifth lens to have a positive refractive power and a suitable surface shape is conducive to converging light while correcting the field curvature and distortion of the optical lens, and improving the imaging quality of the optical lens. More specifically, 1.45 < f5 / f < 2.33; 0.97 < R9 / f < 2.48.

[0080] In some embodiments, the optical lens satisfies the following conditional expressions: 4 mm < f < 4.1 mm; 1.9 mm < EPD < 2.3 mm; 23 mm < TTL < 30 mm; 1.7 < Fno < 2.1; 13° < CRA < 21°; 7 mm < BFL < 8 mm; 140° < FOV < 170°; 7 mm < IH < 9 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the chief ray angle of incidence of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field angle of the optical lens, and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as a large field angle, a large image plane, and a large aperture. More specifically, 4.01 mm < f < 4.04 mm; 1.95 mm < EPD < 2.25 mm; 24.65 mm < TTL < 28.3 mm; 1.79 < Fno < 2.06; 14.08° < CRA < 20.7°; 7.46 mm < BFL < 7.73 mm; 145° < FOV < 161°; 7.58 mm < IH < 8.82 mm.

[0081] 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. 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 of the present invention adopts a lens structure with a hybrid combination of seven glass and plastic lenses, which can improve the thermal stability performance. Specifically, the first lens and the fourth lens are made of glass lenses; the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens are all plastic lenses; adopting a glass-plastic hybrid structure can effectively reduce costs, correct aberrations, reduce the volume, and provide an optical lens product with higher cost performance.

[0082] In some embodiments, the first, second, third, fourth, fifth, sixth, and seventh lenses may be spherical or aspherical lenses. Compared to spherical lenses, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number and size of lenses and achieving better miniaturization. More specifically, in the optical lens provided by the present invention, the second, third, fifth, sixth, and seventh lenses may be aspherical lenses, while the first and fourth lenses may be spherical lenses.

[0083] In various embodiments of the present invention, when the lens is an aspheric lens, the shapes of the aspheric surfaces of the optical lens satisfy the following equations:

[0084]

[0085] 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, and F are the fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients, respectively.

[0086] 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.

[0087] Example 1

[0088] 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, in order from the object side to the imaging surface along the optical axis: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0089] The first lens L1 has negative refractive power, its object-side surface S1 is convex, and its image-side surface S2 is concave;

[0090] The second lens L2 has positive refractive power, its object-side surface S3 is concave, and its image-side surface S4 is convex;

[0091] The third lens L3 has negative refractive power, its object-side surface S5 is concave, and its image-side surface S6 is convex;

[0092] The fourth lens L4 has negative refractive power, its object-side surface S7 is convex, and its image-side surface S8 is concave;

[0093] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex, and its image-side surface S10 is convex;

[0094] The sixth lens L6 has negative refractive power, its object-side surface S11 is convex near the optical axis, and its image-side surface S12 is concave;

[0095] The seventh lens L7 has positive refractive power, its object-side surface S13 is convex, and its image-side surface S14 is convex;

[0096] The object-side surface S15 and the image-side surface S16 of the filter G1 are both flat surfaces;

[0097] The object side surface S17 and the image side surface S18 of the protective glass G2 are both flat surfaces;

[0098] The imaging surface S19 is a plane.

[0099] The second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are plastic aspherical lenses; the first lens L1 and the fourth lens L4 are glass spherical lenses.

[0100] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0101] Table 1-1

[0102]

[0103]

[0104] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0105] Table 1-2

[0106] Face number K B C D E F S3 2.69E+01 -2.49E-03 -8.29E-05 9.58E-06 -8.88E-07 3.83E-08 S4 -7.22E-01 4.98E-04 -2.42E-04 2.68E-05 -1.57E-06 3.49E-08 S5 -3.22E+00 9.82E-04 -4.57E-04 3.81E-05 -1.86E-06 1.67E-08 S6 -4.57E+00 1.35E-03 -4.77E-04 3.17E-05 -1.24E-06 1.94E-08 S9 1.32E+00 3.58E-03 -7.93E-04 7.84E-05 -4.71E-06 9.02E-08 S10 -8.35E+00 -3.94E-03 3.21E-04 -3.50E-05 2.49E-06 -1.05E-07 S11 -1.44E+01 -4.13E-03 1.04E-04 2.23E-07 -7.05E-07 5.05E-08 S12 -5.16E+00 8.66E-04 -1.04E-04 -2.83E-06 6.78E-07 -2.14E-08 S13 -5.97E+00 1.35E-03 -6.21E-05 -7.28E-06 7.24E-07 -1.71E-08 S14 -4.76E-01 -2.06E-04 -1.77E-05 3.84E-06 -2.94E-07 9.93E-09

[0107] In this embodiment, the MTF curve of the optical lens 100 is as follows: Figure 2 shown. Figure 2 The MTF (Modulation Transfer Function) curve for Example 1 is shown, representing the degree of lens imaging modulation at different spatial frequencies across the field of view. The horizontal axis represents spatial frequency (lp / mm), and the vertical axis represents the MTF value. As can be seen from the graph, the MTF value of this embodiment is consistently above 0.45 across the entire field of view. Within the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating excellent imaging quality and detail resolution at both low and high frequencies.

[0108] Example 2

[0109] See also Figure 3 , shown is a schematic structural diagram of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is a concave surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0110] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0111] Table 2-1

[0112]

[0113] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0114] Table 2-2

[0115]

[0116]

[0117] In this embodiment, the MTF curve of the optical lens 200 is as follows: Figure 4 As shown. Figure 4 As can be seen, the MTF value of this embodiment is above 0.3 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0118] Example 3

[0119] See also Figure 5 , shown is a schematic structural diagram of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S7 of the fourth lens L4 is concave; the image-side surface S8 of the fourth lens L4 is convex; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0120] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0121] Table 3-1

[0122]

[0123] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0124] Table 3-2

[0125]

[0126]

[0127] In this embodiment, the MTF curve of the optical lens 300 is as follows: Figure 6 As shown. Figure 6 As can be seen, the MTF value of this embodiment is above 0.48 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution at both low and high frequencies.

[0128] Example 4

[0129] See also Figure 7 , shown is a schematic structural diagram of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 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; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0130] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0131] Table 4-1

[0132]

[0133]

[0134] The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0135] Table 4-2

[0136] Face number K B C D E F S3 4.12E+01 -4.56E-03 -2.47E-04 9.95E-06 2.15E-07 -5.89E-08 S4 -2.41E-01 5.01E-05 -1.15E-04 6.35E-06 -3.82E-07 7.63E-09 S5 -5.91E+00 5.89E-03 -4.16E-04 1.58E-05 -9.02E-07 2.06E-08 S6 -8.21E+00 2.93E-03 -4.39E-04 1.19E-05 -4.36E-08 -6.97E-09 S9 -3.73E-01 -1.76E-04 -1.79E-04 2.10E-05 -1.14E-06 1.89E-08 S10 1.76E+00 -4.15E-03 4.41E-04 -3.21E-05 1.65E-06 -5.11E-08 S11 -4.39E+01 -8.67E-03 3.13E-04 -1.07E-05 -2.07E-07 2.14E-08 S12 -3.21E+00 -3.70E-03 2.15E-04 -1.40E-06 -5.39E-07 1.48E-08 S13 -5.01E+00 4.12E-04 4.38E-05 4.87E-06 -3.37E-07 9.04E-09 S14 -3.56E-01 -4.90E-04 3.33E-05 6.40E-06 -3.31E-07 2.38E-08

[0137] In this embodiment, the MTF curve of the optical lens 400 is as follows: Figure 8 As shown. Figure 8 As can be seen, the MTF value of this embodiment is above 0.4 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0138] Example 5

[0139] See also Figure 9, shown is a schematic structural diagram of an optical lens 500 provided in Example 5 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is concave; the object-side surface S3 of the second lens L2 is convex; the object-side surface S7 of the fourth lens L4 is concave; the image-side surface S8 of the fourth lens L4 is convex; and the image-side surface S10 of the fifth lens L5 is concave; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0140] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0141] Table 5-1

[0142]

[0143]

[0144] The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0145] Table 5-2

[0146] Face number K B C D E F S3 1.58E+01 -5.17E-03 -3.62E-04 4.46E-07 1.14E-06 -9.68E-08 S4 -5.67E-01 2.77E-04 -3.03E-04 2.05E-05 -9.29E-07 1.20E-08 S5 -1.05E+01 6.95E-03 -3.02E-04 9.59E-06 -1.02E-07 -2.36E-08 S6 -4.26E+00 2.62E-03 -3.05E-04 8.09E-06 -3.24E-07 7.08E-09 S9 -4.67E-01 -1.82E-03 6.99E-05 1.44E-05 -1.60E-06 1.10E-07 S10 -3.21E+01 -7.48E-03 6.53E-04 -5.09E-05 5.61E-06 -2.93E-07 S11 -4.50E+01 -1.44E-02 4.45E-04 -1.10E-05 2.04E-06 -3.01E-07 S12 -7.83E+00 -4.34E-03 2.28E-04 9.74E-06 -2.11E-06 7.15E-08 S13 -1.48E+00 -1.68E-03 9.28E-05 1.15E-05 -7.72E-07 1.99E-08 S14 -7.01E-01 -5.52E-04 5.79E-05 1.37E-05 -1.05E-06 6.95E-08

[0147] In this embodiment, the MTF curve of the optical lens 500 is as follows: Figure 10 As shown. Figure 10 As can be seen, the MTF value of this embodiment is above 0.38 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0148] Example 6

[0149] See also Figure 11 , shown is a schematic structural diagram of an optical lens 600 provided in Example 6 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the object-side surface S3 of the second lens L2 is a convex surface; the object-side surface S7 of the fourth lens L4 is a concave surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0150] The relevant parameters of each lens in the optical lens 600 in Example 6 are shown in Table 6-1.

[0151] Table 6-1

[0152]

[0153]

[0154] The surface parameters of the aspheric lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0155] Table 6-2

[0156] Face number K B C D E F S3 -4.50E+01 -2.64E-03 -1.49E-04 1.12E-05 -1.07E-06 3.06E-08 S4 -2.45E-01 -2.99E-04 -2.52E-04 2.78E-05 -1.62E-06 3.35E-08 S5 -3.18E+00 1.07E-03 -4.19E-04 3.78E-05 -1.93E-06 3.07E-08 S6 -4.47E+00 1.75E-03 -4.46E-04 2.66E-05 -9.41E-07 1.43E-08 S9 1.18E+00 4.17E-03 -7.36E-04 6.99E-05 -3.86E-06 5.16E-08 S10 -1.82E+01 -3.11E-03 2.81E-04 -2.38E-05 1.08E-06 -3.67E-08 S11 -4.50E+01 -4.27E-03 1.91E-04 -4.59E-07 -2.08E-06 1.68E-07 S12 -5.18E+00 1.86E-03 -1.39E-04 -6.33E-06 1.06E-06 -3.33E-08 S13 -3.02E+00 1.26E-03 -6.74E-05 -8.93E-07 7.59E-07 -2.59E-08 S14 -2.04E+00 5.95E-04 2.49E-05 8.25E-06 -2.66E-07 2.99E-08

[0157] In this embodiment, the MTF curve of the optical lens 600 is as follows: Figure 12 As shown. Figure 12 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0158] Example 7

[0159] See also Figure 13 , shown is a schematic structural diagram of an optical lens 700 provided in Example 7 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is concave; the object-side surface S3 of the second lens L2 is convex; the object-side surface S7 of the fourth lens L4 is concave; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0160] The relevant parameters of each lens in the optical lens 700 in Example 7 are shown in Table 7-1.

[0161] Table 7-1

[0162]

[0163] The surface parameters of the aspheric lens of the optical lens 700 in Example 7 are shown in Table 7-2.

[0164] Table 7-2

[0165]

[0166]

[0167] In this embodiment, the MTF curve of the optical lens 700 is as follows: Figure 14 As shown. Figure 14 As can be seen, the MTF value of this embodiment is above 0.45 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution at both low and high frequencies.

[0168] Example 8

[0169] See also Figure 15 , shown is a schematic structural diagram of an optical lens 800 provided in Example 8 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is a concave surface; the object-side surface S3 of the second lens L2 is a convex surface; the object-side surface S7 of the fourth lens L4 is a concave surface; and 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.

[0170] The relevant parameters of each lens in the optical lens 800 in Example 8 are shown in Table 8-1.

[0171] Table 8-1

[0172]

[0173] The surface parameters of the aspheric lens of the optical lens 800 in Example 8 are shown in Table 8-2.

[0174] Table 8-2

[0175] Face number K B C D E F S3 -2.51E+01 -3.75E-03 -3.13E-04 -5.86E-07 8.02E-07 -7.78E-08 S4 4.11E-01 -9.98E-05 -1.29E-04 5.15E-06 -2.26E-07 3.44E-10 S5 -5.29E+00 6.63E-03 -4.23E-04 1.85E-05 -8.28E-07 9.85E-09 S6 -7.65E+00 3.60E-03 -4.93E-04 1.13E-05 1.74E-07 -1.41E-08 S9 -3.44E-01 8.23E-05 -1.90E-04 2.30E-05 -1.27E-06 2.31E-08 S10 6.31E-02 -3.81E-03 3.82E-04 -2.98E-05 1.68E-06 -6.53E-08 S11 -4.50E+01 -8.79E-03 2.96E-04 -1.17E-05 -9.59E-08 9.12E-09 S12 -3.66E+00 -3.67E-03 1.93E-04 -1.41E-07 -5.86E-07 1.59E-08 S13 -4.33E+00 3.19E-04 4.55E-05 4.93E-06 -3.33E-07 8.86E-09 S14 -9.16E-01 -4.64E-04 3.91E-05 6.49E-06 -3.09E-07 2.34E-08

[0176] In this embodiment, the MTF curve of the optical lens 800 is as follows: Figure 16 As shown. Figure 16 As can be seen, the MTF value of this embodiment is above 0.45 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution at both low and high frequencies.

[0177] Example 9

[0178] See also Figure 17 , shown is a schematic structural diagram of an optical lens 900 provided in Example 9 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S3 of the second lens L2 is convex; the object-side surface S7 of the fourth lens L4 is concave; the image-side surface S8 of the fourth lens L4 is convex; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0179] The relevant parameters of each lens in the optical lens 900 in Example 9 are shown in Table 9-1.

[0180] Table 9-1

[0181]

[0182]

[0183] The surface parameters of the aspheric lens of the optical lens 900 in Example 9 are shown in Table 9-2.

[0184] Table 9-2

[0185] Face number K B C D E F S3 -4.50E+01 -4.49E-03 -2.38E-04 -5.60E-06 1.40E-06 -7.87E-08 S4 -2.27E-01 4.64E-05 -1.37E-04 7.29E-06 -3.60E-07 8.95E-09 S5 -6.53E+00 6.51E-03 -2.86E-04 1.56E-05 -9.43E-07 3.26E-08 S6 -7.58E+00 3.01E-03 -3.43E-04 1.56E-05 -6.44E-07 2.41E-08 S9 -5.65E-02 7.38E-04 -1.85E-04 2.19E-05 -1.23E-06 3.51E-08 S10 -2.56E+00 -3.23E-03 3.45E-04 -2.49E-05 1.22E-06 -3.32E-08 S11 -4.51E+01 -6.82E-03 3.06E-04 -2.25E-05 8.09E-07 -2.49E-08 S12 -1.61E+00 -3.94E-03 8.93E-05 1.20E-07 -1.64E-07 2.87E-09 S13 -2.34E+00 -1.14E-03 -7.19E-06 6.17E-06 -1.79E-07 2.79E-09 S14 -2.27E+00 -6.96E-04 2.64E-05 3.69E-06 -2.05E-07 1.38E-08

[0186] In this embodiment, the MTF curve of the optical lens 900 is as follows: Figure 18 As shown. Figure 18 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0187] Example 10

[0188] See also Figure 19 , shown is a schematic structural diagram of the optical lens 1000 provided in Example 10 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S3 of the second lens L2 is convex; the object-side surface S7 of the fourth lens L4 is concave; the image-side surface S8 of the fourth lens L4 is convex; and the image-side surface S10 of the fifth lens L5 is concave; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0189] The relevant parameters of each lens in the optical lens 1000 in Example 10 are shown in Table 10-1.

[0190] Table 10-1

[0191]

[0192]

[0193] The surface parameters of the aspheric lens of the optical lens 1000 in Example 10 are shown in Table 10-2.

[0194] Table 10-2

[0195] Face number K B C D E F S3 2.14E+01 -5.70E-03 -3.63E-04 -7.80E-06 2.62E-06 -1.74E-07 S4 -4.84E-01 8.40E-04 -2.73E-04 1.78E-05 -9.71E-07 2.19E-08 S5 -7.56E+00 7.26E-03 -2.11E-04 8.70E-06 -8.23E-07 3.40E-08 S6 -7.71E+00 1.75E-03 -2.16E-04 1.76E-05 -1.33E-06 4.90E-08 S9 -3.39E-01 -1.27E-03 -6.92E-05 2.20E-05 -1.58E-06 5.53E-08 S10 -2.90E+01 -7.08E-03 6.98E-04 -4.22E-05 2.41E-06 -1.27E-07 S11 -4.51E+01 -9.33E-03 3.90E-04 -2.07E-05 2.07E-07 -7.23E-08 S12 -9.54E-01 -3.91E-03 6.72E-05 -3.01E-06 1.56E-07 -7.67E-09 S13 -1.66E+00 -2.01E-03 3.07E-05 1.04E-05 -4.34E-07 8.94E-09 S14 -1.67E+00 -7.23E-04 4.34E-05 8.21E-06 -5.50E-07 3.69E-08

[0196] In this embodiment, the MTF curve of the optical lens 1000 is as follows: Figure 20 As shown. Figure 20 As can be seen, the MTF value of this embodiment is above 0.48 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution at both low and high frequencies.

[0197] Example 11

[0198] See also Figure 21 , shown is a schematic structural diagram of an optical lens 1100 provided in Example 11 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is concave; the object-side surface S3 of the second lens L2 is convex; the object-side surface S7 of the fourth lens L4 is concave; the image-side surface S8 of the fourth lens L4 is convex; and the image-side surface S10 of the fifth lens L5 is concave; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0199] The relevant parameters of each lens in the optical lens 1100 in Example 11 are shown in Table 11-1.

[0200] Table 11-1

[0201]

[0202] The surface parameters of the aspheric lens of the optical lens 1100 in Example 11 are shown in Table 11-2.

[0203] Table 11-2

[0204] Face number K B C D E F S3 4.70E+01 -4.95E-03 -3.32E-04 -9.53E-06 2.28E-06 -1.97E-07 S4 -5.53E-01 2.71E-04 -2.12E-04 1.61E-05 -1.20E-06 3.16E-08 S5 -7.88E+00 5.76E-03 -1.51E-04 1.28E-05 -1.60E-06 6.14E-08 S6 -7.52E+00 9.85E-04 -1.82E-04 1.32E-05 -1.30E-06 5.38E-08 S9 -3.08E-01 -1.68E-03 -5.37E-06 1.49E-05 -1.27E-06 6.02E-08 S10 -4.50E+01 -8.74E-03 8.12E-04 -4.79E-05 2.53E-06 -1.09E-07 S11 -4.50E+01 -1.08E-02 3.96E-04 -7.26E-06 -1.46E-06 8.46E-09 S12 -1.74E+00 -4.19E-03 1.41E-04 2.70E-07 -4.92E-07 1.27E-08 S13 -2.22E+00 -1.76E-03 1.09E-04 9.13E-06 -6.24E-07 1.50E-08 S14 -2.56E+00 -6.95E-04 4.41E-05 1.05E-05 -6.94E-07 4.74E-08

[0205] In this embodiment, the MTF curve of the optical lens 1100 is as follows: Figure 22 As shown. Figure 22 As can be seen, the MTF value of this embodiment is above 0.38 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0206] Example 12

[0207] See also Figure 23 , shown is a schematic structural diagram of an optical lens 1200 provided in Example 12 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the object-side surface S3 of the second lens L2 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0208] The relevant parameters of each lens in the optical lens 1200 in Example 12 are shown in Table 12-1.

[0209] Table 12-1

[0210]

[0211] The surface parameters of the aspheric lens of the optical lens 1200 in Example 12 are shown in Table 12-2.

[0212] Table 12-2

[0213]

[0214]

[0215] In this embodiment, the MTF curve of the optical lens 1200 is as follows: Figure 24 As shown. Figure 24 As can be seen, the MTF value of this embodiment is above 0.5 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, achieving good imaging quality and detail resolution in both low-frequency and high-frequency conditions.

[0216] Example 13

[0217] See also Figure 25 , shown is a schematic structural diagram of an optical lens 1300 provided in Example 13 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S1 of the first lens L1 is a concave surface; the object-side surface S3 of the second lens L2 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0218] The relevant parameters of each lens in the optical lens 1300 in Example 13 are shown in Table 13-1.

[0219] Table 13-1

[0220]

[0221] The surface parameters of the aspheric lens of the optical lens 1300 in Example 13 are shown in Table 13-2.

[0222] Table 13-2

[0223] Face number K B C D E F S3 -4.49E+01 -4.47E-03 -3.16E-04 1.37E-05 1.23E-07 -7.46E-08 S4 -6.50E-01 -6.71E-04 -1.59E-04 4.59E-06 -1.61E-07 -3.58E-10 S5 -5.85E+00 6.24E-03 -3.43E-04 1.02E-05 -5.69E-07 3.48E-08 S6 -1.04E+01 3.70E-03 -3.56E-04 7.77E-06 -4.56E-08 1.06E-08 S9 -1.58E+00 3.38E-03 -4.52E-04 4.04E-05 -2.23E-06 2.55E-08 S10 -8.13E+00 -4.22E-03 2.45E-04 -1.69E-05 4.10E-07 -9.38E-09 S11 3.75E+01 -8.80E-03 4.66E-04 -3.10E-05 3.54E-07 7.04E-08 S12 -8.41E+00 -1.30E-03 1.26E-04 -1.22E-05 3.58E-07 3.46E-09 S13 -8.93E+00 2.48E-03 -6.74E-05 2.06E-06 5.02E-08 -4.28E-10 S14 -2.00E+00 -1.54E-04 3.31E-05 5.81E-06 -7.93E-08 4.77E-09

[0224] In this embodiment, the MTF curve of the optical lens 1300 is as follows: Figure 26 As shown. Figure 26 As can be seen, the MTF value of this embodiment is above 0.48 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases evenly and smoothly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution at both low and high frequencies.

[0225] Please refer to Table 13-1 and Table 13-2, which show the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, real image height IH corresponding to the maximum field of view angle, maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0226] Table 13-1

[0227]

[0228]

[0229] Table 13-2

[0230]

[0231]

[0232] 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. While achieving a good infrared confocal effect, the lens also has one or more advantages such as a large field of view, a large aperture, and miniaturization.

[0233] 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.

[0234] 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 sequentially includes from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose image side is concave; A second lens with a positive optical power, whose image side is convex; A third lens with a negative optical power, whose object side is concave and whose image side is convex; A fourth lens with a negative optical power; A fifth lens with a positive optical power, whose object side is convex; A sixth lens with a negative optical power, whose object side is convex near the optical axis and whose image side is concave; A seventh lens with a positive optical power, whose object side is convex and whose image side is convex; Wherein, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: -1.8 < f1234 / f567 < -0.

6.

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: 5.5 < TTL / f < 7.5; 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: 2.7 < TTL / IH < 3.

8.

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: 70° < FOV / Fno < 90°; 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:

4. The optical lens according to claim 1, wherein: ​ 5. The optical lens according to claim 1, wherein: ​ 6. The optical lens according to claim 1, wherein: ​ 7. The optical lens according to claim 1, wherein: ​ 8. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -2.9 < f6 / f < -1.4; the object-side curvature radius R11 of the sixth lens and the effective focal length f of the optical lens satisfy: 13.5 < R11 / f < 40; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the optical lens satisfy: 0.9 < R12 / f < 1.

8.

9. The optical lens according to claim 1, wherein: The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: 1.3 < f7 / f < 2.1; the object-side curvature radius R13 of the seventh lens and the effective focal length f of the optical lens satisfy: 1 < R13 / f < 2.4; the image-side curvature radius R14 of the seventh lens and the effective focal length f of the optical lens satisfy: -5.2 < R14 / f < -1.

4.

10. The optical lens according to claim 1, wherein: The object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy: 0.7 < (R11 - R12) / (R11 + R12) < 1; the object-side curvature radius R13 of the seventh lens and the image-side curvature radius R14 of the seventh lens satisfy: |(R13 + R14) / (R13 - R14)| < 0.7.

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