Optical lens

Abstract

The invention provides an optical lens, which sequentially comprises a first lens with positive focal power from an object side to an imaging surface along an optical axis, a second lens with negative focal power, a third lens with positive focal power and a fourth lens with negative focal power from the object side to the imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has negative focal power; the fourth lens has negative focal power, the object side surface of the fourth lens is a convex surface near the optical axis, and the image side surface of the fourth lens is a concave surface near the optical axis; the fifth lens has positive focal power, the object side surface of the fifth lens is a convex surface near the optical axis, and the image side surface of the fifth lens is a convex surface; the sixth lens has positive focal power; the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface near the optical axis; the total optical length TTL of the optical lens and the effective focal length f of the optical lens meet the following conditions: 1.1 lt; tTL / flt; and 1.3. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

Description

Technical Field

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

[0002] With the popularity of remote work and online education, video conferencing has become an indispensable part of people's daily life and work, and the quality of video conferencing depends largely on the optical lens of the video conferencing, which puts higher requirements on the video conferencing lens. For example, in order to provide clear video quality, video conferencing lenses usually need to provide high resolution, such as 1080p or 4K; for example, in order to effectively capture the participants in the conference room, the video conferencing lens is often required to better blur the background and highlight the main body of the participants; in order to provide good video quality in a dimly lit environment, the video conferencing lens is usually required to have a larger aperture. Traditional video conferencing lenses have more or less some limitations, such as low resolution and poor imaging in low light or dim environments. Therefore, there is an urgent need to provide an optical lens that can meet the needs of video conferencing. Summary of the invention

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

[0004] The present invention provides an optical lens, which comprises seven lenses in total, and includes the following lenses in order from the object side to the imaging surface along the optical axis: The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; a third lens having negative optical power; a fourth lens element having negative optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; A fifth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is convex; a sixth lens having positive refractive power; The seventh lens element has a negative optical power, the object side surface of which is concave, and the image side surface of which is concave near the optical axis; The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.1 <TTL / f<1.3。

[0005] Further preferably, the effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 4.1 mm <f / Fno<4.6mm。

[0006] Further preferably, the Abbe number Vd1 of the first lens satisfies: Vd1>80; the Abbe number Vd1 of the first lens and the Abbe number Vd3 of the third lens satisfy: 23 <Vd1-Vd3<59。

[0007] Further preferably, the combined focal length f123 of the first lens, the second lens and the third lens and the center thickness CT1 of the first lens, the center thickness CT2 of the second lens and the center thickness CT3 of the third lens satisfy: 3.2 <f123 / (CT1+CT2+CT3)<3.7。

[0008] Further preferably, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens satisfies the effective focal length f of the optical lens: 1.2 <f1234 / f<1.8。

[0009] Further preferably, the total optical length TTL of the optical lens and the real image height ih corresponding to the maximum half field angle of the optical lens satisfy: 1.5 <TTL / ih<1.8。

[0010] Further preferably, a sum ΣCT of the center thicknesses of the first lens to the seventh lens along the optical axis and a distance TD from the object side surface of the first lens to the image side surface of the seventh lens on the optical axis satisfy: 0.6<ΣCT / TD<0.8.

[0011] Further preferably, a center thickness CT4 of the fourth lens, a center thickness CT5 of the fifth lens, and a distance CT56 between the fifth lens and the sixth lens on the optical axis satisfy: 15<(CT4+CT5) / CT56<27.

[0012] Further preferably, the effective focal length f of the optical lens, the center thickness CT6 of the sixth lens, the distance CT67 between the sixth lens and the seventh lens on the optical axis, and the center thickness CT7 of the seventh lens satisfy: 3.2 <f / (CT6+CT67+CT7)<4.2。

[0013] Further preferably, the clear semi-aperture CSD72 of the image side end of the seventh lens and the clear semi-aperture sag SAGX72 of the image side end of the seventh lens satisfy: 4.5<|CSD72 / SAGX72|<12.

[0014] Compared with the prior art, the optical lens provided by the present invention adopts seven lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as miniaturization, large aperture, large image height, high pixels, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0016] Figure 2 Graph showing the astigmatism of the optical lens in Example 1 of the present invention.

[0017] Figure 3 4 is a graph showing the F~Tan (Theta) distortion curve of the optical lens in Example 1 of the present invention.

[0018] Figure 4 Graph showing the axial aberration of the optical lens in Example 1 of the present invention.

[0019] Figure 5 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0020] Figure 6 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0021] Figure 7 Graph showing the astigmatism of the optical lens in Embodiment 2 of the present invention.

[0022] Figure 8 4 is a graph showing the F~Tan (Theta) distortion curve of the optical lens in Example 2 of the present invention.

[0023] Fig. 9 Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

[0024] Fig.10 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0025] Fig.11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0026] Fig.12 4 is an astigmatism curve diagram of the optical lens in Example 3 of the present invention.

[0027] Fig.13 4 is a graph showing the F~Tan (Theta) distortion curve of the optical lens in Example 3 of the present invention.

[0028] Fig.14 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0029] Fig.15Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0030] Fig.16 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0031] Fig.17 4 is an astigmatism curve diagram of the optical lens in Example 4 of the present invention.

[0032] Fig.18 4 is a F~Tan (Theta) distortion curve of the optical lens in Example 4 of the present invention.

[0033] Fig.19 4 is an axial aberration curve diagram of the optical lens in Example 4 of the present invention.

[0034] Fig. 20 Graph showing the vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0035] Fig.21 Schematic diagram of the structure of the optical lens in Example 5 of the present invention.

[0036] Fig. 22 4 is an astigmatism curve diagram of the optical lens in Example 5 of the present invention.

[0037] Fig.23 4 is a graph showing the F~Tan (Theta) distortion curve of the optical lens in Example 5 of the present invention.

[0038] Fig.24 Graph showing the axial aberration of the optical lens in Embodiment 5 of the present invention.

[0039] Fig.25 Graph showing the vertical axis chromatic aberration of the optical lens in Example 5 of the present invention.

[0040] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0041] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application, and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0042] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0043] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0044] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0045] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0046] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0047] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0048] The optical lens provided by the embodiment of the present invention comprises seven lenses in total, and the optical lens comprises, in order from the object side to the imaging surface along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0049] In some embodiments, the first lens may have a positive focal power, with its object side being convex and its image side being concave. The second lens may have a negative focal power, with its object side being convex and its image side being concave. The third lens may have a negative focal power, with its object side being either concave or convex and its image side being either concave or convex. The fourth lens may have a negative focal power, with its object side being convex near the optical axis and its image side being concave near the optical axis. The fifth lens may have a positive focal power, with its object side being convex near the optical axis and its image side being convex. The sixth lens may have a positive focal power, with its object side being either concave or convex and its image side being either concave or convex. The seventh lens may have a negative focal power, with its object side being concave and its image side being concave near the optical axis.

[0050] In some embodiments, the optical lens may further include a diaphragm, which may be located between the object side and the first lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image formation.

[0051] In some embodiments, the optical lens may further include a filter, which is 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 the normal imaging.

[0052] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.1 < TTL / f < 1.3. When the above conditional formula is satisfied, by reasonably setting the ratio of the total optical length of the optical lens (i.e., the distance from the object side of the first lens to the imaging surface of the optical lens on the optical axis) to the effective focal length, not only can the length of the optical lens be effectively limited to achieve the miniaturization and light-weight design of the optical lens, but also the telephoto optical lens is beneficial to better achieve the portrait shooting effect with a small depth of field, blurring the background of the person and highlighting the main body of the person.

[0053] In some embodiments, the effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 4.1 mm < f / Fno < 4.6 mm. When the above conditional formula is satisfied, it is ensured that the optical lens has a large aperture, enabling the optical lens to achieve high-definition imaging even in a relatively dim environment, reducing the noise influence caused by too weak light, and thus improving the imaging quality.

[0054] In some embodiments, the Abbe number Vd1 of the first lens satisfies: Vd1 > 80; the Abbe number Vd1 of the first lens and the Abbe number Vd3 of the third lens satisfy: 23 < Vd1 - Vd3 < 59. When the above two conditional expressions are satisfied, the first lens and the third lens can have reasonable refractive indices, the materials of the first lens and the third lens can be matched, thereby enabling the optical lens to have better chromatic aberration correction ability, improving the resolution of the optical lens, and improving the imaging quality of the optical lens; and further, Vd1 > 80 ensures low dispersion of the first lens, effectively reducing the chromatic aberration of the optical system, which is beneficial to improving the imaging quality.

[0055] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the central thickness CT1 of the first lens, the central thickness CT2 of the second lens, and the central thickness CT3 of the third lens satisfy: 3.2 < f123 / (CT1 + CT2 + CT3) < 3.7. When the above conditional expression is satisfied, the aberration of the optical lens can be reduced by controlling the combined focal length of the first lens, the second lens, and the third lens, and at the same time, the processability of the first lens, the second lens, and the third lens can be improved by controlling the central thicknesses of the first lens, the second lens, and the third lens on the optical axis.

[0056] In some embodiments, the combined focal length f1234 of the first lens, the second lens, the third lens, and the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 < f1234 / f < 1.8. When the above conditional expression is satisfied, the spherical aberration of the first four lenses of the optical lens can be constrained within a reasonable range by controlling the ratio of the combined focal length of the first lens, the second lens, the third lens, and the fourth lens to the effective focal length of the optical lens within a reasonable range, improving the imaging quality of the system; and the air gap between adjacent lenses can be effectively reduced, which is beneficial to reducing the overall optical length of the optical lens.

[0057] In some embodiments, the overall optical length TTL of the optical lens and the true image height ih corresponding to the maximum half field of view angle of the optical lens satisfy: 1.5 < TTL / ih < 1.8. When the above conditional expression is satisfied, it is beneficial for the optical lens to have a small length on the basis of a large image height to meet the requirements of miniaturized design; and by controlling the ratio of the overall optical length of the optical lens to the true half image height, the overall image height and length of the optical lens can be reasonably adjusted, improving the assembly feasibility of the optical lens.

[0058] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis and the distance TD on the optical axis from the object side surface of the first lens to the image side surface of the seventh lens satisfy: 0.6 < ∑CT / TD < 0.8. When the above conditional expression is satisfied, the overall length of the optical lens can be controlled by controlling the sum of the central thicknesses of the first lens to the seventh lens on the optical axis and the distance on the optical axis from the object side surface of the first lens to the image side surface of the seventh lens, and the spacing between the lenses can be reasonably arranged to improve the overall assembly feasibility of the optical lens.

[0059] In some embodiments, the central thickness CT4 of the fourth lens, the central thickness CT5 of the fifth lens, and the spacing CT56 on the optical axis between the fifth lens and the sixth lens satisfy: 15 < (CT4 + CT5) / CT56 < 27. When the above conditional expression is satisfied, by reasonably controlling the ratio of the central thickness of the fourth lens, the central thickness of the fifth lens, and the interval on the optical axis between the fifth lens and the sixth lens, the distortion of the optical lens can be reasonably controlled, enabling the optical lens to have good distortion performance, ensuring the high image quality characteristics of the optical lens, and ensuring the imaging quality of the optical lens.

[0060] In some embodiments, the effective focal length f of the optical lens, the central thickness CT6 of the sixth lens, the spacing CT67 on the optical axis between the sixth lens and the seventh lens, and the central thickness CT7 of the seventh lens satisfy: 3.2 < f / (CT6 + CT67 + CT7) < 4.2. When the above conditional expression is satisfied, the contribution of the third-order distortion of the sixth lens and the seventh lens can be reasonably constrained, keeping the image quality of the marginal field of view within a reasonable range.

[0061] In some embodiments, the clear aperture semi-diameter CSD72 at the image side end of the seventh lens and the sagittal height SAGX72 of the clear aperture semi-diameter at the image side end of the seventh lens satisfy: 4.5 < |CSD72 / SAGX72| < 12. When the above conditional expression is satisfied, by reasonably limiting the clear aperture semi-diameter at the image side end of the seventh lens and the sagittal height of the clear aperture semi-diameter at the image side end of the seventh lens, the surface shape of the image side surface of the seventh lens can be prevented from being overly curved, improving the imaging quality of the optical lens and also facilitating the reduction of the processing difficulty of the seventh lens.

[0062] 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 f123 of the first lens, the second lens, and the third lens satisfy: 0.95 < f1234 / f123 < 1.3. When the above conditional formula is satisfied, by restricting f1234 / f123 within a reasonable range, the object side end of the optical lens can have sufficient light converging ability, thereby shortening the total length of the optical lens and meeting the requirement of ultra-thin optical lens; at the same time, the combined focal length of the first lens, the second lens, the third lens, and the fourth lens is controlled to balance the aberration generated by the first four lenses of the optical lens and the aberration generated by the last three lenses, which is beneficial to obtaining better imaging quality and achieving high resolution of the optical lens.

[0063] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the combined focal length f4567 of the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: -0.1 < f123 / f4567 < -0.01. When the above conditional formula is satisfied, it is possible to balance the overall aberration of the optical lens, improve the imaging quality of the optical lens, reasonably control the light path, avoid the excessive steepness of the light path resulting in too high sensitivity of the lens of the optical lens, and achieve miniaturization of the optical lens.

[0064] In some embodiments, the curvature radius R7 of the object side surface of the fourth lens and the curvature radius R8 of the image side surface of the fourth lens satisfy: 0.01 < (R7 - R8) / (R7 + R8) < 0.3. When the above conditional formula is satisfied, the fourth lens can have good processability by controlling the curvature radii of the object side surface and the image side surface of the fourth lens.

[0065] In some embodiments, the curvature radius R10 of the image side surface of the fifth lens and the distance CT56 between the fifth lens and the sixth lens on the optical axis satisfy: -95 < R10 / CT56 < -40. When the above conditional formula is satisfied, the interval between the fifth lens and the sixth lens on the optical axis and the curvature radius of the image side surface of the fifth lens can be controlled to make the fifth lens have good processability, and at the same time, the assembly stability of the fifth lens and the sixth lens can be improved.

[0066] In some embodiments, the sagittal height SAG51 of the clear aperture radius at the object side end of the fifth lens and the central thickness CT5 of the fifth lens satisfy: -0.3 < |SAGX51 / CT5| < -0.1. When the above conditional formula is satisfied, by controlling the relationship between the sagittal height of the clear aperture radius at the object side end of the fifth lens and the central thickness of the fifth lens on the optical axis, the sensitivity of the production and manufacturing of the fifth lens can be reduced, which is beneficial to the processing and forming of the fifth lens, thereby improving production efficiency.

[0067] In some embodiments, the total optical length TTL of the optical lens, the true image height ih corresponding to the maximum half field of view angle of the optical lens, and the effective focal length f of the optical lens satisfy: 6.5 mm < TTL × (ih / f) < 7.5 mm. When the above conditional formula is satisfied, by controlling the optical power of the optical lens and ensuring that the optical lens has a large image height, astigmatism and distortion can be effectively reduced, and the imaging quality of the optical lens can be greatly improved; further, by reasonably controlling the total optical length of the optical lens, the true half image height of the optical lens, and the effective focal length of the optical lens, the characteristics of a large image plane and ultra-thinness of the optical lens are ensured, and it is ensured that the optical lens can achieve high-pixel imaging.

[0068] In some embodiments, the distance CT23 between the second lens and the third lens on the optical axis, the distance CT45 between the fourth lens and the fifth lens on the optical axis, and the distance CT34 between the third lens and the fourth lens on the optical axis satisfy: 1 < (CT23 + CT45) / CT34 < 10. When the above conditional formula is satisfied, the distances between the second lens, the third lens, the fourth lens, and the fifth lens in the optical axis direction are reasonably controlled, which is convenient for reasonably controlling the distances between the four lenses, can effectively ensure the structural feasibility of the optical lens, and is convenient for the assembly of the optical lens.

[0069] In some embodiments, the curvature radius R1 of the object side surface of the first lens, the curvature radius R2 of the image side surface of the first lens, and the central thickness CT1 of the first lens satisfy: 4 < |R1 - R2| / CT1 < 20. When the above conditional formula is satisfied, it is ensured that the first lens of the optical lens has a more reasonable shape to reasonably bear the optical power of the optical lens and balance the aberration generated by the subsequent lenses.

[0070] In some embodiments, the optical lens satisfies the conditional formula: 7.5 mm < f < 8.3 mm, 9 mm < TTL < 10 mm, Fno < 2, 5.5 mm < ih < 6 mm, 65° < FOV < 75°, where f represents the effective focal length of the optical lens, TTL represents the total 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 half field of view angle of the optical lens, and FOV represents the maximum field of view angle of the optical lens. Satisfying the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least: a smaller total optical length; a larger imaging surface, which can be matched with a larger-sized chip to achieve high-definition imaging; a larger aperture value, enabling the lens to achieve high-definition imaging even in a darker environment; and the characteristics of long focal length, small field of view angle, and short depth of field, which can better blur the background and突出 the subject when shooting distant scenes or people.

[0071] In some embodiments, the seven lenses in the optical lens can all be plastic lenses or glass-plastic mixed material matching structure. Preferably, the optical lens of the present invention adopts a seven-piece glass-plastic mixed lens structure, which can make the optical lens better match the large target chip to achieve high-definition imaging, and can also achieve the miniaturization of the optical lens, the reasonable balance of large image surface and large field of view. Specifically, the first lens can be a glass lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are all plastic lenses; the first lens is made of glass material, which can improve the thermal stability of the optical lens, reduce aberrations and distortions, and make the optical lens imaging clearer and sharper.

[0072] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens may be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of lenses, and better realizing miniaturization of lenses. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens in the optical lens provided by the present invention may be aspherical lenses.

[0073] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations: ; Among them, z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, K is the quadratic surface coefficient, B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0074] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0075] Example 1 See also Figure 1, shown is a schematic diagram of the structure of the optical lens 100 provided in Example 1 of the present invention, and the optical lens 100 includes, along the optical axis from the object side to the imaging surface S17, an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and a filter G1.

[0076] The first lens L1 has positive refractive power, its object side surface S1 is convex, and its image side surface S2 is concave; The second lens L2 has negative refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave; The third lens L3 has negative refractive power, an object-side surface S5 thereof is convex at the near optical axis, and an image-side surface S6 thereof is concave at the near optical axis; The fourth lens L4 has negative refractive power, an object-side surface S7 thereof is convex at the near optical axis, and an image-side surface S8 thereof is concave at the near optical axis; The fifth lens L5 has positive refractive power, its object-side surface S9 is convex at the near optical axis, and its image-side surface S10 is convex; The sixth lens L6 has positive refractive power, its object-side surface S11 is concave, and its image-side surface S12 is convex; The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis; The object side surface S15 and the image side surface S16 of the filter G1 are both planes; The imaging surface S17 is a plane.

[0077] The first lens L1 is a glass aspherical lens; the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all plastic aspherical lenses.

[0078] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0079] Table 1-1 The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0080] Table 1-2 In this embodiment, the astigmatism curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are shown in FIG. Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0081] Figure 2 The astigmatism curve of the optical lens 100 in this embodiment is shown, which represents the astigmatism of light in the meridian image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the field angle (unit: °). It can be seen from the figure that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1mm, indicating that the optical lens 100 can correct the astigmatism well.

[0082] Figure 3 The F~Tan (Theta) distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion of different field angles on the imaging surface, with the horizontal axis representing the distortion value (unit: %) and the vertical axis representing the field angle (unit: °). It can be seen from the figure that the distortion value is controlled within ±1%, indicating that the optical lens 100 can correct the distortion well.

[0083] Figure 4 The axial aberration curve of the optical lens 100 in this embodiment is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within ±0.03mm, indicating that the optical lens 100 can correct the axial aberration well.

[0084] Figure 5 The vertical axis chromatic aberration curve of the optical lens 100 in this embodiment is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface, the horizontal axis represents the vertical axis chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 100 can correct the chromatic aberration well.

[0085] Example 2 See also Figure 6 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object side surface S5 of the third lens L3 is a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

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

[0087] Table 2-1 The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0088] Table 2-2 In this embodiment, the astigmatism curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 200 are shown in FIG. Figure 7 , Figure 8 , Fig. 9 , Fig.10 shown.

[0089] from Figure 7 It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 200 can correct the astigmatism well.

[0090] from Figure 8 It can be seen that the distortion value is controlled within ±1%, indicating that the optical lens 200 can correct the distortion well.

[0091] from Fig. 9 It can be seen 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.

[0092] from Fig.10 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0093] Example 3 See also Fig.11 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object-side surface S5 of the third lens L3 is a concave surface; the image-side surface S6 of the third lens L3 is a convex surface; the object-side surface S11 of the sixth lens L6 is a convex surface at the near optical axis; the image-side surface S12 of the sixth lens L6 is a concave surface at the near optical axis; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0094] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0095] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0096] Table 3-2 In this embodiment, the astigmatism curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown in FIG. Fig.12 , Fig.13, Fig.14 , Fig.15 shown.

[0097] from Fig.12 It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 300 can correct the astigmatism well.

[0098] from Fig.13 It can be seen that the distortion value is controlled within ±1%, indicating that the optical lens 300 can correct the distortion well.

[0099] from Fig.14 It can be seen 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.

[0100] from Fig.15 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0101] Example 4 See also Fig.16 , shown is a schematic diagram of the structure of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0102] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0103] Table 4-1 The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0104] Table 4-2 In this embodiment, the astigmatism curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 400 are shown as follows: Fig.17 , Fig.18 , Fig.19 , Fig. 20 shown.

[0105] from Fig.17 It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 400 can correct the astigmatism well.

[0106] from Fig.18It can be seen that the distortion value is controlled within ±1%, indicating that the optical lens 400 can correct the distortion well.

[0107] from Fig.19 It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 400 can correct the axial aberration well.

[0108] from Fig. 20 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1μm, indicating that the optical lens 400 can correct chromatic aberration well.

[0109] Example 5 See also Fig.21 , shown is a schematic diagram of the structure of an optical lens 500 provided in Example 5 of the present invention. Compared with Example 1, the main differences of this embodiment are: the object-side surface S5 of the third lens L3 is a concave surface; the object-side surface S11 of the sixth lens L6 is a convex surface at the near optical axis; the image-side surface S12 of the sixth lens L6 is a concave surface at the near optical axis; 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 500 in Example 5 are shown in Table 5-1.

[0111] Table 5-1 The surface parameters of the aspheric lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0112] Table 5-2 In this embodiment, the astigmatism curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 500 are shown in FIG. Fig. 22 , Fig.23 , Fig.24 , Fig.25 shown.

[0113] from Fig. 22 It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.1 mm, indicating that the optical lens 500 can correct the astigmatism well.

[0114] from Fig.23 It can be seen that the distortion value is controlled within ±1%, indicating that the optical lens 500 can correct the distortion well.

[0115] from Fig.24It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 500 can correct the axial aberration well.

[0116] From Fig.25 It can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 500 can correct the chromatic aberration well.

[0117] Please refer to Table 6 for the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the true image height ih corresponding to the maximum half field of view angle, the chief ray angle of incidence CRA at the maximum image height, the maximum field of view angle FOV, and the values corresponding to each conditional formula in each embodiment.

[0118] Table 6 Combining the above embodiments, the optical lens provided by the present invention adopts a seven-piece glass-plastic hybrid structure. Through specific surface shape settings and reasonable focal power distribution, it has the following beneficial effects: 1. It has a long focal length (7.5 mm < f < 8.3 mm), which is beneficial to better achieve the portrait shooting effect with a small depth of field, blur the background, and highlight the subject; 2. It has a large aperture (Fno < 2), which is beneficial to increasing the light input of the lens, enabling the lens to achieve high-definition imaging even in a dim environment; 3. It has a large image plane, can match a larger-sized chip, and can achieve high-pixel imaging; the total length is short (TTL < 10 mm), which is beneficial to miniaturization and can directly perform vertical imaging without the need to deflect light rays through a prism for imaging; 4. Adopting a glass-plastic hybrid structure (1MG6P) makes the optical lens have good thermal stability; at the same time, the Abbe number Vd1 of the first lens > 80, with low dispersion, effectively reducing the chromatic aberration of the optical system and being beneficial to improving the imaging quality; 5. It can reasonably correct the overall aberration of the optical lens, has a small distortion (within ±1%), and can provide a more accurate and clear imaging effect.

[0119] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0120] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: Along the optical axis from the object side to the imaging surface, it includes: The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; a third lens having negative optical power; a fourth lens element having negative optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; A fifth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is convex; a sixth lens having positive refractive power; The seventh lens element has a negative optical power, the object side surface of which is concave, and the image side surface of which is concave near the optical axis; The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.1 <TTL / f<1.3。 2. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 4.1 mm <f / Fno<4.6mm。 3. The optical lens according to claim 1, characterized in that: The Abbe number Vd1 of the first lens satisfies: Vd1>80; the Abbe number Vd1 of the first lens and the Abbe number Vd3 of the third lens satisfy: 23 <Vd1-Vd3<59。 4. The optical lens according to claim 1, characterized in that: The combined focal length f123 of the first lens, the second lens and the third lens and the center thickness CT1 of the first lens, the center thickness CT2 of the second lens and the center thickness CT3 of the third lens satisfy: 3.2 <f123 / (CT1+CT2+CT3)<3.7。 5. The optical lens according to claim 1, characterized in that: The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the effective focal length f of the optical lens satisfy: 1.2 <f1234 / f<1.8。 6. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the real image height ih corresponding to the maximum half field angle of the optical lens satisfy: 1.5 <TTL / ih<1.8。 7. The optical lens according to claim 1, characterized in that: A sum ΣCT of the center thicknesses of the first lens to the seventh lens along the optical axis and a distance TD from the object side surface of the first lens to the image side surface of the seventh lens on the optical axis satisfy: 0.6<ΣCT / TD<0.

8.

8. The optical lens according to claim 1, characterized in that: The center thickness CT4 of the fourth lens, the center thickness CT5 of the fifth lens, and the distance CT56 between the fifth lens and the sixth lens on the optical axis satisfy: 15<(CT4+CT5) / CT56<27.

9. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens, the center thickness CT6 of the sixth lens, the distance CT67 between the sixth lens and the seventh lens on the optical axis, and the center thickness CT7 of the seventh lens satisfy: 3.2 <f / (CT6+CT67+CT7)<4.2。 10. The optical lens according to claim 1, characterized in that: The semi-aperture CSD72 of the image side end of the seventh lens and the semi-aperture sag SAGX72 of the image side end of the seventh lens satisfy the following: 4.5<|CSD72 / SAGX72|<12.

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