Optical lens

Abstract

The present invention provides an optical lens. The optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The following relationships are satisfied between the height L of the lens barrel and the effective focal length f of the optical lens: 0.27 < L / f < 0.30; between the refractive index N1 of the first lens and the effective focal length f1 of the first lens: 17.22 mm < N1 × f1 < 18.96 mm; between the spacing distance EP01 between the object-side end face of the lens barrel and the object-side face of the first spacer element along the optical axis extension direction and the edge thickness ET1 of the non-effective diameter region of the first lens: 1.69 < EP01 / ET1 < 2.66; between the inner diameter d0s of the object-side end face of the lens barrel and the inner diameter d1s of the object-side face of the first spacer element: 1.18 < d0s / d1s < 1.25. The present invention solves the problem in the prior art that the optical lens has poor reliability due to meeting the requirements of long focal length.

Description

Technical Field

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

[0002] All along, the imaging system has been a key factor in differentiating different smartphones. From mainstream mid-range phones to top-of-the-line flagship phones, the main camera wide-angle lens is essential. Most also have an ultra-wide-angle lens, but the telephoto lens generally becomes exclusive to high-end flagship phones. However, with the increasing demand for smartphone imaging systems, there is a trend for telephoto lenses to spread from high-end flagship phones to mainstream mid-range phones and even entry-level low-end phones.

[0003] However, when designing a telephoto lens, due to the relatively small degree of freedom in the design of the front aperture, the stress peak at the edge of the lens located in the front is easily concentrated at a certain point. During the reliability test, the front lens is likely to be broken, failing to meet the reliability requirements.

[0004] That is to say, in the prior art, there is a problem that the optical lens meets the telephoto requirements but has poor reliability. Summary of the Invention

[0005] The main object of the present invention is to provide an optical lens to solve the problem that the optical lens in the prior art meets the telephoto requirements but has poor reliability.

[0006] To achieve the above object, according to one aspect of the present invention, an optical lens is provided, including a lens barrel, a lens group and a spacer element group assembled in the lens barrel.

[0007] The lens group includes a first lens, a second lens, a third lens and a fourth lens in sequence along the optical axis from the object side to the image side.

[0008] The spacer element group includes at least a first spacer element, and the first spacer element is located between the first lens and the second lens and at least partially contacts the image side surface of the first lens.

[0009] The height L of the lens barrel and the effective focal length f of the optical lens satisfy: 0.27 < L / f < 0.30;

[0010] The refractive index N1 of the first lens and the effective focal length f1 of the first lens satisfy: 17.22 mm < N1 × f1 < 18.96 mm;

[0011] The spacing distance EP01 between the object side end surface of the lens barrel and the object side surface of the first spacer element along the optical axis extension direction and the edge thickness ET1 of the non-effective diameter region of the first lens satisfy: 1.69 < EP01 / ET1 < 2.66;

[0012] The inner diameter d0s of the object-side end face of the lens barrel and the inner diameter d1s of the object-side face of the first spacer element satisfy: 1.18 < d0s / d1s < 1.25.

[0013] According to another aspect of the present invention, there is provided an optical lens, which includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens with a positive optical power, a second lens with a positive optical power, a third lens with a negative optical power, and a fourth lens with a positive optical power along the optical axis from the object side to the image side; the spacer element group includes at least a first spacer element, and the first spacer element is located between the first lens and the second lens and is at least partially in contact with the image-side face of the first lens; the lens barrel height L and the effective focal length f of the optical lens satisfy: 0.27 < L / f < 0.30; the refractive index N1 of the first lens and the effective focal length f1 of the first lens satisfy: 17.22 mm < N1×f1 < 18.96 mm; the central thickness CT1 of the first lens, the air gap T12 between the first lens and the second lens on the optical axis, and the spacing distance EP01 between the object-side end face of the lens barrel and the object-side face of the first spacer element along the optical axis extension direction satisfy: 1.29 < (CT1 + T12) / EP01 < 1.72; the effective focal length f1 of the first lens, the inner diameter d0s of the object-side end face of the lens barrel and the inner diameter d1s of the object-side face of the first spacer element satisfy: 5.65 < f1 / (d0s - d1s) < 7.65.

[0014] According to another aspect of the present invention, there is provided an optical lens, which includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens with a positive optical power, a second lens with a positive optical power, a third lens with a negative optical power, and a fourth lens with a positive optical power along the optical axis from the object side to the image side; the spacer element group includes at least a first spacer element, and the first spacer element is located between the first lens and the second lens and is at least partially in contact with the image-side face of the first lens; the air gap T12 between the first lens and the second lens on the optical axis and the sum ∑AT of the air gaps between adjacent two lenses between the first lens and the fourth lens satisfy: 0.05 < T12 / ∑AT < 0.17, and the curvature radius R2 of the image-side face of the first lens and the curvature radius R3 of the object-side face of the second lens satisfy: -25.55 < R3 / R2 < 29.93; the maximum thickness CP1 of the first spacer element in the optical axis extension direction and the air gap T12 between the first lens and the second lens on the optical axis satisfy: 5.45 < (CP1 + EP12) / T12 < 21.25.

[0015] Furthermore, the axial distance SAG11 between the intersection of the object side surface of the first lens and the optical axis and the vertex of the effective radius of the non-effective diameter region of the object side surface of the first lens, and the outer diameter D1s of the object side surface of the first spacer element satisfy: 0.09 < |SAG11| / D1s < 0.12.

[0016] Furthermore, the central thickness CT1 of the first lens, the air gap T12 between the first lens and the second lens on the optical axis, and the spacing distance EP01 between the object side end face of the lens barrel and the object side surface of the first spacer element along the optical axis extension direction satisfy: 1.29 < (CT1 + T12) / EP01 < 1.72.

[0017] Furthermore, the radius of curvature R1 of the object side surface of the first lens and the outer diameter D0s of the object side end face of the lens barrel satisfy: 0.95 < R1 / D0s < 1.19.

[0018] Furthermore, the outer diameter D1s of the object side surface of the first spacer element, the spacing distance EP01 between the object side end face of the lens barrel and the object side surface of the first spacer element along the optical axis extension direction, and the central thickness CT1 of the first lens satisfy: 8.96 mm < D1s / (EP01 / CT1) < 10.89 mm.

[0019] Furthermore, the air gap T12 between the first lens and the second lens on the optical axis, and the sum ∑AT of the air gaps between adjacent two lenses from the first lens to the fourth lens satisfy: 0.05 < T12 / ∑AT < 0.17.

[0020] Furthermore, the effective focal length f1 of the first lens, the inner diameter d0s of the object side end face of the lens barrel, and the inner diameter d1s of the object side surface of the first spacer element satisfy: 5.65 < f1 / (d0s - d1s) < 7.65.

[0021] Furthermore, the spacer element group further includes a first auxiliary spacer element. The first auxiliary spacer element is located between the first spacer element and the second lens and is at least partially in contact with the image side surface of the first spacer element. The outer diameter D1bm of the image side surface of the first auxiliary spacer element and the inner diameter d1bm of the image side surface of the first auxiliary spacer element satisfy: 1.12 < D1bm / d1bm < 1.30.

[0022] Furthermore, the spacer element group further includes a second spacer element. The second spacer element is located between the second lens and the third lens, and the second spacer element is partially in contact with the image side surface of the second lens. The maximum thickness CP1 of the first spacer element in the optical axis extension direction, the spacing distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis extension direction, and the central thickness CT2 of the first lens satisfy: 1.38 < (CP1 + EP12) / CT2 < 1.65.

[0023] Furthermore, the following condition is satisfied among the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, and the inner diameter d2s of the object side surface of the second spacer element: 2.49 < (R3 + R4) / d2s < 9.56.

[0024] Furthermore, the following condition is satisfied among the combined focal length f12 of the first lens and the second lens, the maximum thickness CP1 of the first spacer element in the optical axis extending direction, and the spacing distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element in the optical axis extending direction: 4.47 < f12 / (CP1 + EP12) < 5.49.

[0025] Furthermore, the spacer element group further includes a second spacer element and a third spacer element. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens. The third spacer element is located between the third lens and the fourth lens and is in partial contact with the image side surface of the third lens. The minimum inner diameter of the first spacer element is greater than the minimum inner diameter of the second spacer element, and the minimum inner diameter of the second spacer element is greater than the minimum inner diameter of the third spacer element.

[0026] The following condition is satisfied between the inner diameter d1s of the object side surface of the first spacer element and the inner diameter d2s of the object side surface of the second spacer element: 0.77 < d2s / d1s < 0.84;

[0027] The following condition is satisfied between the inner diameter d3s of the object side surface of the third spacer element and the inner diameter d2s of the object side surface of the second spacer element: 0.85 < d3s / d2s < 0.89;

[0028] The following condition is satisfied between the inner diameter d1m of the image side surface of the first spacer element and the inner diameter d2m of the image side surface of the second spacer element: 0.81 < d2m / d1m < 0.90;

[0029] The following condition is satisfied between the inner diameter d3m of the image side surface of the third spacer element and the inner diameter d2m of the image side surface of the second spacer element: 0.86 < d3m / d2m < 0.89.

[0030] Furthermore, the optical lens further includes an auxiliary barrel. The auxiliary barrel is located on the object side of the barrel. The connection between the auxiliary barrel and the barrel, the height L of the barrel, the height Lb of the auxiliary barrel, the outer diameter D0bm of the image side end surface of the auxiliary barrel, and the inner diameter d0bs of the object side end surface of the auxiliary barrel satisfy: 1.98 mm-1 < L / Lb / (D0bm - d0bs) < 2.34 mm-1.

[0031] Furthermore, the following condition is satisfied between the inner diameter d0bs of the object side end surface of the auxiliary barrel and the maximum effective radius DT11 of the object side surface of the first lens: 1.96 < d0bs / DT11 < 2.04.

[0032] Furthermore, the first lens has a positive optical power, the second lens has a positive optical power, the third lens has a negative optical power, and the fourth lens has a positive optical power.

[0033] Furthermore, the object side surface of the first lens is convex; the object side surface of the second lens is convex, and the image side surface of the second lens is concave; the object side surface of the third lens is convex, and the image side surface of the third lens is concave; the image side surface of the fourth lens is convex.

[0034] Applying the technical solution of the present invention, the optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens, a third lens and a fourth lens along the optical axis from the object side to the image side; the spacer element group at least includes a first spacer element, and the first spacer element is located between the first lens and the second lens and is at least partially in contact with the image side surface of the first lens; the following relationships are satisfied between the lens barrel height L and the effective focal length f of the optical lens: 0.27 < L / f < 0.30; the following relationship is satisfied between the refractive index N1 of the first lens and the effective focal length f1 of the first lens: 17.22 mm < N1×f1 < 18.96 mm; the following relationship is satisfied between the spacing distance EP01 along the optical axis extension direction between the object side end surface of the lens barrel and the object side surface of the first spacer element and the edge thickness ET1 of the non-effective diameter region of the first lens: 1.69 < EP01 / ET1 < 2.66; the following relationship is satisfied between the inner diameter d0s of the object side end surface of the lens barrel and the inner diameter d1s of the object side surface of the first spacer element: 1.18 < d0s / d1s < 1.25.

[0035] The optical lens of the present application is composed of a lens barrel, four lenses and at least one spacer element. When the following relationships are satisfied between the lens barrel height L and the effective focal length f of the optical lens: 0.27 < L / f < 0.30; and the following relationship is satisfied between the refractive index N1 of the first lens and the effective focal length f1 of the first lens: 17.22 mm < N1×f1 < 18.96 mm, by restricting the focal length of the first lens and the optical lens and the lens barrel height, the convergence degree of light when passing through the first lens is optimized, so that the light converges reasonably in the subsequent space to achieve long focal length imaging. However, the aperture of the long focal length lens is relatively small, resulting in relatively concentrated force on the edge of the first lens. In order to improve the convergence degree of light when passing through the first lens, the first lens can be made of glass material. However, the glass material has low toughness, resulting in a risk of cracking at the edge of the first lens during the reliability test, making the optical lens unable to meet the reliability requirements.

[0036] In order not to affect the telephoto performance of the optical lens and the degree of light convergence when passing through the first lens, the present application constrains both EP01 / ET1 and d0s / d1s within reasonable ranges to control the space at the front end of the first lens, so as to provide an installation position for the retaining ring. The retaining ring can not only share part of the stress of the lens barrel, but also abut against the object side of the first lens, so that the position where the first lens abuts against the retaining ring is subjected to the pressure of the retaining ring, thereby dispersing the force on the first lens, effectively avoiding the risk of glass lens breakage, improving the reliability of the optical lens, and ensuring the stability of lens assembly at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0038] Figure 1 Shows the dimension marking diagram of the optical lens of an alternative embodiment of the present invention;

[0039] Figure 2 Shows the dimension marking diagram of the optical lens of another alternative embodiment of the present invention;

[0040] Figure 3 Shows the schematic structural diagram of the optical lens of Embodiment 1-1 of the present invention;

[0041] Figure 4 Shows the schematic structural diagram of the optical lens of Embodiment 1-2 of the present invention;

[0042] Figure 5 Shows the schematic structural diagram of the optical lens of Embodiment 1-3 of the present invention;

[0043] Figures 6 to 8 Respectively show the axial chromatic aberration, astigmatism curve and distortion curve of the optical lens of Embodiment 1 of the present invention;

[0044] Figure 9 Shows the schematic structural diagram of the optical lens of Embodiment 2-1 of the present invention;

[0045] Figure 10 Shows the schematic structural diagram of the optical lens of Embodiment 2-2 of the present invention;

[0046] Figure 11 Shows the schematic structural diagram of the optical lens of Embodiment 2-3 of the present invention;

[0047] Figures 12 to 14 Respectively show the axial chromatic aberration, astigmatism curve and distortion curve of the optical lens of Embodiment 2 of the present invention;

[0048] Figure 15 Shows a schematic structural diagram of the optical lens of Embodiment 3-1 of the present invention;

[0049] Figure 16 Shows a schematic structural diagram of the optical lens of Embodiment 3-2 of the present invention;

[0050] Figure 17 Shows a schematic structural diagram of the optical lens of Embodiment 3-3 of the present invention;

[0051] Figures 18 to 20 Respectively show the axial chromatic aberration, astigmatism curve and distortion curve of the optical lens of Embodiment III of the present invention;

[0052] Figure 21 Shows the overall stress simulation diagram of the optical lens of an alternative embodiment of the present invention at the first lens position;

[0053] Figure 22 Shows Figure 21 The stress simulation diagram of the optical lens in the side view direction at the first lens position in;

[0054] Figure 23 Shows the overall stress simulation diagram of the optical lens in an example at the first lens position;

[0055] Figure 24 Shows Figure 23 The stress simulation diagram of the optical lens in the side view direction at the first lens position in.

[0056] Among them, the above-mentioned drawings include the following reference numerals:

[0057] 10, bearing groove; 20, retaining ring; P0b, auxiliary lens barrel; P0, lens barrel; E1, first lens; P1, first spacer element; P1b, first auxiliary spacer element; P1c, second auxiliary spacer element; E2, second lens; P2, second spacer element; E3, third lens; P3, third spacer element; E4, fourth lens; S1, object side of the first lens; S2, image side of the first lens; S3, object side of the second lens; S4, image side of the second lens; S5, object side of the third lens; S6, image side of the third lens; S7, object side of the fourth lens; S8, image side of the fourth lens. Detailed implementation manners

[0058] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0059] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0060] In the present invention, unless otherwise stated, the directional terms such as "upper, lower, top, bottom" are generally in reference to the direction shown in the drawings, or in reference to the component itself in the vertical, perpendicular or gravitational direction; similarly, for ease of understanding and description, "inner, outer" refer to the inner and outer of the contour of each component itself, but the above directional terms are not used to limit the present invention.

[0061] It should be noted that in this specification, the expressions such as first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0062] In the drawings, for ease of illustration, the thickness, size and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shape shown in the drawings is shown by way of example. That is, the spherical or aspherical shape is not limited to the spherical or aspherical shape shown in the drawings. The drawings are for illustrative purposes only and are not drawn to an exact scale.

[0063] In this text, 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 judgment of the surface shape in the paraxial region can be based on the judgment method of those with ordinary knowledge in this field, and the positive and negative of the R value (R refers to the radius of curvature in the paraxial region, usually the R value on the lens database (lens data) in optical software) is used to judge the convexity and concavity. Taking the object side as an example, when the R value is positive, it is judged as a convex surface, and when the R value is negative, it is judged as a concave surface; taking the image side as an example, when the R value is positive, it is judged as a concave surface, and when the R value is negative, it is judged as a convex surface. In this application, the left side is the object side and the right side is the image side.

[0064] In order to solve the problem in the prior art that the optical lens has poor reliability due to meeting the long focal length requirement, the present invention provides an optical lens.

[0065] Such as Figures 1 to 20As shown in the figure, the optical lens includes a lens barrel, a lens group, and a spacer element group assembled in the lens barrel. The lens group includes a first lens, a second lens, a third lens, and a fourth lens in sequence along the optical axis from the object side to the image side. The spacer element group includes at least a first spacer element. The first spacer element is located between the first lens and the second lens and is at least partially in contact with the image side surface of the first lens. The relationship between the lens barrel height L and the effective focal length f of the optical lens satisfies: 0.27 < L / f < 0.30. The relationship between the refractive index N1 of the first lens and the effective focal length f1 of the first lens satisfies: 17.22mm < N1×f1 < 18.96mm. The relationship between the interval distance EP01 along the optical axis extension direction between the object side end surface of the lens barrel and the object side surface of the first spacer element and the edge thickness ET1 of the non-effective diameter region of the first lens satisfies: 1.69 < EP01 / ET1 < 2.66. The relationship between the inner diameter d0s of the object side end surface of the lens barrel and the inner diameter d1s of the object side surface of the first spacer element satisfies: 1.18 < d0s / d1s < 1.25.

[0066] The optical lens of the present application is composed of a lens barrel, four lenses, and at least one spacer element. When the relationship between the lens barrel height L and the effective focal length f of the optical lens satisfies: 0.27 < L / f < 0.30, and the relationship between the refractive index N1 of the first lens and the effective focal length f1 of the first lens satisfies 17.22mm < N1×f1 < 18.96mm, by restricting the focal length of the first lens and the optical lens and the lens barrel height, the convergence degree of light passing through the first lens is optimized, so that the light converges reasonably in the subsequent space to achieve long focal length imaging. However, the aperture of the long focal length lens is relatively small, resulting in relatively concentrated stress on the edge of the first lens. In order to improve the convergence degree of light passing through the first lens, the first lens can be made of glass material. However, the toughness of the glass material is relatively low, resulting in a risk of cracking at the edge of the first lens during the reliability test, making the optical lens unable to meet the reliability requirements.

[0067] In order not to affect the long focal length performance of the optical lens and the convergence degree of light passing through the first lens, the present application restricts both EP01 / ET1 and d0s / d1s within a reasonable range to control the space at the front end of the first lens, so as to provide an installation position for the retaining ring 20. The retaining ring 20 can not only share part of the stress of the lens barrel, but also abut against the object side surface of the first lens, so that the position where the first lens abuts against the retaining ring 20 is subjected to the pressure of the retaining ring 20, thereby dispersing the stress on the first lens, effectively avoiding the risk of cracking of the glass lens, improving the reliability of the optical lens, and ensuring the stability of the lens group erection.

[0068] Table 1 below shows a comparison of the stress simulation diagrams of an optional embodiment of the present application and the optical lens in the prior art.

[0069] Table 1

[0070]

[0071] In addition, referring to Table 1 and Figures 21 to 24 as shown, Figure 21 shows the overall stress simulation diagram of the optical lens at the first lens position when L / f = 0.28, N1×f1 = 18.96, EP01 / ET1 = 1.90, and d0s / d1s = 1.24. Figure 22 shows the stress simulation diagram in the side view direction of the optical lens at the first lens position when L / f = 0.28, N1×f1 = 18.96, EP01 / ET1 = 1.90, and d0s / d1s = 1.24. It can be seen from Figure 21 and Figure 22 that the stress is mainly concentrated on the object side surface of the first lens. Figure 23 shows the overall stress simulation diagram of the optical lens at the first lens position when L / f = 0.28, N1×f1 = 18.96, EP01 / ET1 = 1.47, and d0s / d1s = 1.09. Figure 24 shows the stress simulation diagram in the side view direction of the optical lens at the first lens position when L / f = 0.28, N1×f1 = 18.96, EP01 / ET1 = 1.47, and d0s / d1s = 1.09. It can be seen from Figure 23 and Figure 24 that the stress is mainly concentrated on the outer ring surface position of the first lens. From the above Table 1 and Figure 21 and Figure 23 it can be known that the stress concentration degree of the first lens in Lens 1 is relatively high, concentrated at the position where the first lens abuts against the inner wall surface of the lens barrel, and the stress peak value is relatively large. When the first lens is made of glass, it is relatively easy to break. While the stress on the first lens in Lens 2 is relatively uniform and the stress peak value is relatively small. When the first lens is made of glass, it is not easy to break. And when EP01 / ET1 is greater than 2.66 and d0s / d1s is greater than 1.25, the front-end space of the first lens is relatively large, resulting in the lens group being unable to be stably assembled. Therefore, there is no stress simulation diagram of Lens 3.

[0072] The above-mentioned Lens 1 and Lens 3 can be understood as lenses in the prior art, while Lens 2 is the optical lens under application. From the above Table 1 and Figures 21 to 24 it can be known that the optical lens has good reliability when 0.27 < L / f < 0.30, 17.22 mm < N1×f1 < 18.96 mm, 1.69 < EP01 / ET1 < 2.66, and 1.18 < d0s / d1s < 1.25.

[0073] It should be noted that in this application, EP01 / ET1 and d0s / d1s are restricted within a reasonable range to control the space at the front end of the first lens within a reasonable range, so as to solve the problem that when L / f is in the range of 0.27 to 0.33 and N1×f1 is in the range of 17.22 mm to 18.96 mm, the first lens is prone to breakage when it is a glass lens. This is particularly applicable to the design of telephoto lenses. When EP01 / ET1 and d0s / d1s meet the above ranges, the purpose of reducing the stress concentration of the first lens and improving the reliability can be achieved, and it does not depend on the optical power of the lens and the surface shape of the lens. The optical power and surface shape of the lens are further optimizations of the optical lens on this basis. Each lens can be positive or negative according to the design requirements of the actual optical system, and the surface shape of each lens can also be convex or concave according to the design requirements of the optical system. As long as the optical system satisfies: 0.27 < L / f < 0.30, 17.22 mm < N1×f1 < 18.96 mm, 1.69 < EP01 / ET1 < 2.66, and 1.18 < d0s / d1s < 1.25, the requirements of both long focal length and reliability can be met.

[0074] For example, the first lens has a positive optical power, the second lens has a positive optical power, the third lens has a negative optical power, and the fourth lens has a positive optical power. Another example is that the object side surface of the first lens is convex, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, and the image side surface of the fourth lens is convex. The optical lens can be simulated through software and / or tools such as ANSYS, ABAQUS, etc. The optical lens in this application uses ANSYS for simulation. During the simulation process using software and / or tools such as the above, the surface shape of each lens can be simulated according to the built-in surface shape of the software and / or tool used and adjusted appropriately.

[0075] In some alternative embodiments, the axial distance SAG11 between the intersection point of the object side surface of the first lens and the optical axis and the vertex of the effective radius of the non-effective diameter region of the object side surface of the first lens and the outer diameter D1s of the object side surface of the first spacer element satisfy: 0.09 < |SAG11| / D1s < 0.12. By restricting |SAG11| / D1s within a reasonable range, the bending degree of the object side surface of the first lens and the size of the first lens can be ensured, and at the same time, the bearing area between the first spacer element and the first lens can be ensured, which is beneficial to ensuring the assembly stability of the optical lens.

[0076] In some alternative embodiments, the following relationship is satisfied among the central thickness CT1 of the first lens, the air gap T12 between the first lens and the second lens on the optical axis, and the spacing distance EP01 between the object-side end face of the lens barrel and the object-side surface of the first spacer element along the optical axis extension direction: 1.29 < (CT1 + T12) / EP01 < 1.72. By limiting (CT1 + T12) / EP01 within a reasonable range, the edge thickness and the central thickness of the first lens can be ensured to be within a reasonable range, thereby ensuring the shape of the first lens. At the same time, interference between the first lens and the second lens can be avoided, which is beneficial to improving the structural stability.

[0077] In some alternative embodiments, the following relationship is satisfied between the radius of curvature R1 of the object-side surface of the first lens and the outer diameter D0s of the object-side end face of the lens barrel: 0.95 < R1 / D0s < 1.19. If R1 / D0s is less than 0.95, the radius of curvature of the object-side surface of the first lens is small, which will cause the refraction intersection point to be biased to the right, resulting in a large degree of deflection of light rays. At the same time, some imaging light rays cannot enter the effective diameter region of the object-side surface of the first lens. If R1 / D0s is greater than 1.19, the radius of curvature of the object-side surface of the first lens is large, which will cause the refraction intersection point to be biased to the left. At the same time, some non-imaging light rays will enter the effective diameter region of the object-side surface of the first lens, affecting the imaging quality. Limiting R1 / D0s within a reasonable range can ensure the imaging quality of the optical lens.

[0078] In some alternative embodiments, the following relationship is satisfied among the outer diameter D1s of the object-side surface of the first spacer element, the spacing distance EP01 between the object-side end face of the lens barrel and the object-side surface of the first spacer element along the optical axis extension direction, and the central thickness CT1 of the first lens: 8.96 mm < D1s / (EP01 / CT1) < 10.89 mm. By limiting D1s / (EP01 / CT1) within a reasonable range, while ensuring that the central thickness and the edge thickness of the first lens are within a reasonable range, the structural shape of the first lens is ensured. At the same time, the stability of the bearing between the first lens and the first spacer element is ensured. If D1s / (EP01 / CT1) is greater than 10.89 mm, it means that D1s is large, which is likely to cause an increase in the size of the optical lens and is not conducive to the miniaturization of the optical lens; or it means that CT1 is large and EP01 is small, which is likely to make the shape of the first lens difficult to manufacture. If D1s / (EP01 / CT1) is less than 8.96 mm, it means that D1s is small, which is likely to cause unstable bearing between the first spacer element and the first lens; or it means that CT1 is small and EP01 is large, which is likely to make the shape of the first lens difficult to manufacture. At the same time, it is also likely to affect the refraction path of the predetermined light path in the first lens.

[0079] In some alternative embodiments, the air gap T12 between the first lens and the second lens on the optical axis and the sum ∑AT of the air gaps between two adjacent lenses among the first lens to the fourth lens satisfy: 0.05 < T12 / ∑AT < 0.17. If T12 / ∑AT is less than 0.05, it is likely to result in a small air gap T12 between the first lens and the second lens on the optical axis, and interference is likely to occur between the first lens and the second lens. If T12 / ∑AT is greater than 0.17, it is not conducive to the rapid convergence of light rays into the second lens, and it is not conducive to meeting the requirements of telephoto performance. By restricting T12 / ∑AT within a reasonable range, it can be ensured that after the light rays are converged by the first lens, they can quickly enter the second lens, which is conducive to the rapid convergence of light rays, and thus conducive to meeting the requirements of telephoto performance.

[0080] In some alternative embodiments, the effective focal length f1 of the first lens, the inner diameter d0s of the object-side end face of the lens barrel, and the inner diameter d1s of the object-side face of the first spacer element satisfy: 5.65 < f1 / (d0s - d1s) < 7.65. By restricting f1 / (d0s - d1s) within a reasonable range, the degree of deflection of light rays passing through the first lens can be ensured, which is conducive to the imaging light rays passing smoothly through the inner diameter of the object-side end face of the lens barrel and the inner diameter of the object-side face of the first spacer element, reducing the reflection of large-angle deflected light rays on the inner wall of the lens barrel or the first spacer element, and is conducive to reducing the risk of stray light generated at the front end of the optical lens.

[0081] In some alternative embodiments, the spacer element group further includes a first auxiliary spacer element. The first auxiliary spacer element is located between the first spacer element and the second lens and is at least partially in contact with the image-side face of the first spacer element. The outer diameter D1bm of the image-side face of the first auxiliary spacer element and the inner diameter d1bm of the image-side face of the first auxiliary spacer element satisfy: 1.12 < D1bm / d1bm < 1.30. When the interval between the first lens and the second lens is large, in order to ensure the assembly stability of the lenses, a spacer element with a relatively thick thickness is usually used between them to ensure the bearing force on the first lens and the second lens. At the same time, in order to improve the stray light of the first spacer element with a large thickness, the first auxiliary spacer element is added. When the first auxiliary spacer element satisfies the above conditional formula, the stray light reflected onto the first spacer element can be effectively improved through the aperture adjustment of the first auxiliary spacer element, thereby improving the imaging quality.

[0082] In some alternative embodiments, the spacer element group further includes a second spacer element located between the second lens and the third lens, and the second spacer element is in contact with the image-side surface portion of the second lens. The maximum thickness CP1 of the first spacer element in the optical axis extension direction, the spacing distance EP12 between the image-side surface of the first spacer element and the object-side surface of the second spacer element in the optical axis extension direction, and the central thickness CT2 of the first lens satisfy: 1.38 < (CP1 + EP12) / CT2 < 1.65. By restricting (CP1 + EP12) / CT2 within a reasonable range, the thickness ratio of the second lens can be effectively controlled within a reasonable range, ensuring the forming stability of the second lens and effectively avoiding the risk of assembly deformation of the second lens during the assembly process.

[0083] In some alternative embodiments, the curvature radius R3 of the object-side surface of the second lens, the curvature radius R4 of the image-side surface of the second lens, and the inner diameter d2s of the object-side surface of the second spacer element satisfy: 2.49 < (R3 + R4) / d2s < 9.56. If (R3 + R4) / d2s is greater than 9.56, the curvature radius R3 of the object-side surface of the second lens and the curvature radius R4 of the image-side surface of the second lens are too large, while the inner diameter d2s of the object-side surface of the second spacer element is too small, which will cause the marginal light rays passing through the second lens to not smoothly pass through the second spacer element, affecting the imaging quality. If (R3 + R4) / d2s is less than 2.49, the curvature radius R3 of the object-side surface of the second lens and the curvature radius R4 of the image-side surface of the second lens are too small, while the inner diameter d2s of the object-side surface of the second spacer element is too large, which will cause non-imaging light rays to enter the subsequent imaging system, affecting the imaging quality and also possibly having the risk of light leakage. By restricting (R3 + R4) / d2s within the range of 2.49 to 9.56, the curvature radii of the object-side surface and the image-side surface of the second lens are adapted to the inner diameter of the second spacer element, thereby reducing the generation of stray light and ensuring that the imaging light rays smoothly pass through the second spacer element.

[0084] In some alternative embodiments, the combined focal length f12 of the first lens and the second lens, the maximum thickness CP1 of the first spacer element in the optical axis extension direction, and the spacing distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element in the optical axis extension direction satisfy: 4.47 < f12 / (CP1 + EP12) < 5.49. By controlling the relationship between the combined focal length of the first lens and the second lens, the maximum thickness of the first spacer element in the optical axis extension direction, and the spacing distance between the image side surface of the first spacer element and the object side surface of the second spacer element in the optical axis extension direction, the edge distance between the first lens and the second lens and the edge thickness of the second lens can be constrained within a reasonable range, reducing interference generated during the assembly of the first lens and the second lens, avoiding problems such as interference during the assembly process due to the too-close edge distance between the first lens and the second lens, which affects the lens performance, and at the same time, avoiding problems such as excessive distance between the two or too-thin edge thickness of the second lens resulting in unstable assembly, improving the stability of the optical lens assembly, ensuring the performance of light transmission between the first lens and the second lens while ensuring the stability of the optical lens assembly, reducing the generation of stray light, and at the same time ensuring the refractive performance of the first lens and the second lens for light, ensuring the imaging performance of the optical lens.

[0085] In some alternative embodiments, the spacer element group further includes a second spacer element and a third spacer element. The second spacer element is located between the second lens and the third lens and contacts the image-side surface portion of the second lens. The third spacer element is located between the third lens and the fourth lens and contacts the image-side surface portion of the third lens. The minimum inner diameter of the first spacer element is greater than the minimum inner diameter of the second spacer element, and the minimum inner diameter of the second spacer element is greater than the minimum inner diameter of the third spacer element. The ratio of the inner diameter d2s of the object-side surface of the second spacer element to the inner diameter d1s of the object-side surface of the first spacer element satisfies: 0.77 < d2s / d1s < 0.84; the ratio of the inner diameter d3s of the object-side surface of the third spacer element to the inner diameter d2s of the object-side surface of the second spacer element satisfies: 0.85 < d3s / d2s < 0.89; the ratio of the inner diameter d2m of the image-side surface of the second spacer element to the inner diameter d1m of the image-side surface of the first spacer element satisfies: 0.81 < d2m / d1m < 0.90; the ratio of the inner diameter d3m of the image-side surface of the third spacer element to the inner diameter d2m of the image-side surface of the second spacer element satisfies: 0.86 < d3m / d2m < 0.89. By designing the minimum inner diameters of the first spacer element, the second spacer element, and the third spacer element to gradually decrease, it is beneficial for the light to show a gradually shrinking trend during the transmission from the first lens to the fourth lens. While ensuring the long focal length performance of the optical lens, the first spacer element, the second spacer element, and the third spacer element can effectively absorb stray light to ensure the imaging quality of the optical lens. In addition, by optimizing the ratio of the inner diameter of the object-side surface of the first spacer element to the inner diameter of the object-side surface of the second spacer element and the ratio of the inner diameter of the image-side surface of the first spacer element to the inner diameter of the image-side surface of the second spacer element, the light emitted from the first lens can smoothly enter the second lens and exit from the second lens and enter the third lens, which is beneficial for controlling the deflection degree of the light in the second lens, avoiding large-angle deflection of the light at the second lens, and facilitating the smooth transition of the light from the first lens to the third lens. By optimizing the ratio of the inner diameter of the object-side surface of the third spacer element to the inner diameter of the object-side surface of the second spacer element and the ratio of the inner diameter of the image-side surface of the third spacer element to the inner diameter of the image-side surface of the second spacer element, the light emitted from the second lens can smoothly enter the third lens and exit from the third lens and enter the fourth lens, which is beneficial for controlling the deflection degree of the light in the third lens, avoiding large-angle deflection of the light at the third lens, and facilitating the smooth transition of the light from the second lens to the fourth lens. By restricting the inner diameter sizes of the first spacer element, the second spacer element, and the third spacer element, it is beneficial for the light to smoothly transition between the second lens and the third lens, reduce large-angle deflection, reduce the generation of stray light, improve the imaging quality, and at the same time facilitate the optical lens to meet the requirements of image height.

[0086] In some alternative embodiments, the optical lens further includes an auxiliary barrel. The auxiliary barrel is located on the object side of the barrel. The connection between the auxiliary barrel and the barrel, the height L of the barrel, the height Lb of the auxiliary barrel, the outer diameter D0bm of the image-side end face of the auxiliary barrel, and the inner diameter d0bs of the object-side end face of the auxiliary barrel satisfy: 1.98 mm -1 <L / Lb / (D0bm - d0bs) < 2.34 mm -1 . Since the inner diameter d0s of the object-side end face of the barrel in this application is greater than the inner diameter d1s of the object side of the first spacer element, more marginal rays enter the object-side end face of the barrel, making it easy to form stray light. By adding the auxiliary barrel, part of the light entering the optical lens can be blocked on the object side of the barrel to reduce the amount of marginal rays entering and improve the imaging quality of the optical lens. By controlling the relationship between the height of the barrel, the height of the auxiliary barrel, the outer diameter of the image-side end face of the auxiliary barrel, and the inner diameter of the object-side end face of the auxiliary barrel, while ensuring the overall size of the optical lens, the degree of blocking of the marginal rays by the auxiliary barrel can be controlled. While ensuring that the optical lens meets the telephoto performance, the entry of non-imaging marginal rays into the optical system is reduced to improve the imaging quality of the optical lens.

[0087] In some alternative embodiments, the object-side end face of the barrel has a bearing groove 10. The bearing groove 10 communicates with the outer peripheral surface of the barrel. A part of the auxiliary barrel extends into the bearing groove 10, and the auxiliary barrel and the barrel can be connected by glue.

[0088] In some alternative embodiments, the ratio between the inner diameter d0bs of the object-side end face of the auxiliary barrel and the maximum effective radius DT11 of the object side of the first lens satisfies: 1.96 < d0bs / DT11 < 2.04. If d0bs / DT11 is less than 1.96, the inner diameter of the object-side end face of the auxiliary barrel is too small, and the maximum effective radius of the object side of the first lens is too large. The auxiliary barrel is likely to block the maximum effective radius of the object side of the first lens, resulting in the blocking of imaging rays that can pass through the maximum effective radius position of the object side of the first lens and affecting the imaging quality. If d0bs / DT11 is greater than 2.04, the inner diameter of the object-side end face of the auxiliary barrel is too large, and the maximum effective radius of the object side of the first lens is too small, which easily causes non-imaging rays to enter the optical lens and affects the imaging quality. By controlling the ratio of the inner diameter of the object-side end face of the auxiliary barrel to the maximum effective radius of the object side of the first lens, the amount of light passing through the auxiliary barrel is adapted to the maximum effective radius of the object side of the first lens, thereby improving the imaging quality.

[0089] In addition, in another alternative embodiment of the present application, an optical lens is further provided. The optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens with a positive optical power, a second lens with a positive optical power, a third lens with a negative optical power, and a fourth lens with a positive optical power along the optical axis from the object side to the image side. The spacer element group includes at least a first spacer element. The first spacer element is located between the first lens and the second lens and is at least partially in contact with the image side surface of the first lens. The following relationships are satisfied among the lens barrel height L, the effective focal length f of the optical lens: 0.27 < L / f < 0.30. The following relationship is satisfied between the refractive index N1 of the first lens and the effective focal length f1 of the first lens: 17.22 mm < N1 × f1 < 18.96 mm. The following relationship is satisfied among the central thickness CT1 of the first lens, the air gap T12 between the first lens and the second lens on the optical axis, and the interval distance EP01 between the object side end surface of the lens barrel and the object side surface of the first spacer element along the optical axis extension direction: 1.29 < (CT1 + T12) / EP01 < 1.72. The following relationship is satisfied among the effective focal length f1 of the first lens, the inner diameter d0s of the object side end surface of the lens barrel, and the inner diameter d1s of the object side surface of the first spacer element: 5.65 < f1 / (d0s - d1s) < 7.65.

[0090] The optical lens of the present application is composed of a lens barrel, four lenses and at least one spacer element. When the following relationships are satisfied among the lens barrel height L, the effective focal length f of the optical lens: 0.27 < L / f < 0.30, and between the refractive index N1 of the first lens and the effective focal length f1 of the first lens: 17.22 mm < N1 × f1 < 18.96 mm, by restricting the focal length of the first lens and the optical lens, as well as the lens barrel height, the convergence degree of light passing through the first lens is optimized, so that the light converges reasonably in the subsequent space to achieve telephoto imaging. However, the aperture of the telephoto lens is relatively small, resulting in relatively concentrated stress on the edge of the first lens. In order to improve the convergence degree of light passing through the first lens, the first lens can be made of glass material. However, the toughness of the glass material is relatively low, resulting in a risk of cracking at the edge of the first lens during the reliability test, making the optical lens unable to meet the reliability requirements. By restricting (CT1 + T12) / EP01 and f1 / (d0s - d1s) within a reasonable range, the edge thickness and the central thickness of the first lens can be ensured to be within a reasonable range, thereby ensuring the shape of the first lens, which is beneficial to improving the structural strength of the first lens, effectively reducing the risk of cracking of the first lens, and at the same time avoiding interference between the first lens and the second lens, which is beneficial to improving the structural stability, and further beneficial to improving the reliability of the optical lens. In addition, the deflection angle of light in the first lens can be controlled to reduce the reflection of large-angle deflected light on the inner wall of the lens barrel or the first spacer element, which is beneficial to reducing the risk of stray light generated at the front end of the optical lens.

[0091] In addition, in another alternative embodiment of the present application, an optical lens is further provided. The optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens with a positive optical power, a second lens with a positive optical power, a third lens with a negative optical power, and a fourth lens with a positive optical power along the optical axis from the object side to the image side. The spacer element group includes at least a first spacer element. The first spacer element is located between the first lens and the second lens and is at least partially in contact with the image side surface of the first lens. The air gap T12 between the first lens and the second lens on the optical axis and the sum ∑AT of the air gaps between two adjacent lenses among the first lens and the fourth lens satisfy: 0.05 < T12 / ∑AT < 0.17. The curvature radius R2 of the image side surface of the first lens and the curvature radius R3 of the object side surface of the second lens satisfy: -25.55 < R3 / R2 < 29.93. The maximum thickness CP1 of the first spacer element in the optical axis extension direction and the air gap T12 between the first lens and the second lens on the optical axis satisfy: 5.45 < (CP1 + EP12) / T12 < 21.25.

[0092] By restricting T12 / ∑AT within a reasonable range, it can be ensured that after the light rays are converged by the first lens, they can quickly enter the second lens, which is beneficial to the rapid convergence of light rays and further beneficial to meeting the requirements of telephoto performance. However, due to the small air gap between the first lens and the second lens on the optical axis, when the first lens is installed, it is easy to interfere with the second lens, which is not conducive to the installation of the first lens. By controlling the relationship between the curvature radius of the image side surface of the first lens, the curvature radius of the object side surface of the second lens, the maximum thickness of the first spacer element in the optical axis extension direction, and the air gap between the first lens and the second lens on the optical axis, it is beneficial to control the edge gap between the first lens and the second lens. When the first lens is installed, the first spacer element abuts against the first lens first, avoiding interference with the second lens during the installation of the first lens, and improving the convenience of assembling the first lens.

[0093] Of course, other parametric formulas in the above embodiment may also be included in this embodiment, which will not be elaborated here one by one.

[0094] Optionally, the above optical lens may further include a protective glass for protecting the photosensitive element located on the imaging surface.

[0095] The optical lens in the present application may employ multiple lenses, such as the four lenses described above. In the present application, at least one of the lens surfaces of each lens is an aspherical surface. The characteristics of an aspherical lens are that the curvature continuously changes from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality.

[0096] However, those skilled in the art should understand that without departing from the technical solution claimed in the present application, the number of lenses constituting the optical lens can be changed to obtain the various results and advantages described in this specification. For example, although the four-lens example is described in the embodiment, the optical lens is not limited to including four lenses. If necessary, the optical lens may also include other numbers of lenses.

[0097] Figure 1 The schematic diagram of the dimension marking of the optical lens of an alternative embodiment of the present application is shown. Figure 2 The schematic diagram of the dimension marking of the optical lens of another alternative embodiment of the present application is exemplified. Figure 1 Parameters such as d1s, d1m, D1s, D1m, d1bm, D1bm, d2s, d2m, d3s, d3m, d0s, D0s, d0bs, EP01, CP1, EP12, L, Lb, etc. are marked. Figure 2 Parameters such as SAG11, ET1, etc. are marked to clearly and intuitively understand the meaning of the parameters. For the convenience of describing the surface shape of the optical lens and specific lenses, these parameters will no longer be shown in the accompanying drawings when specific embodiments are described later.

[0098] The following further describes with reference to the drawings specific examples of the surface shape and parameters of the optical lens applicable to the above embodiments.

[0099] It should be noted that in the following Example 1, there are three examples of Embodiment 1-1, Embodiment 1-2, and Embodiment 1-3. In Example 2, there are three examples of Embodiment 2-1, Embodiment 2-2, and Embodiment 2-3. In Example 3, there are three examples of Embodiment 3-1, Embodiment 3-2, and Embodiment 2-3. The curvature radii, central thicknesses, and other parameters of the first lens to the fourth lens of the optical lens under the three examples in the same embodiment, as well as the spacing distances and higher-order term coefficients between the lenses, are the same, but the thicknesses, inner diameters, and outer diameters of the lens barrel, the first spacer element, the second spacer element, and the third spacer element, and the shapes of some lenses are different. Or rather, the main structures for imaging are the same, while the auxiliary structures for imaging are different.

[0100] Example 1

[0101] As Figures 3 to 8 shown, the optical lens of Example 1 is described. Figure 3 The structural schematic diagram of the optical lens of Embodiment 1-1 is shown, Figure 4 The structural schematic diagram of the optical lens of Embodiment 1-2 is shown, Figure 5 The structural schematic diagram of the optical lens of Embodiment 1-3 is shown.

[0102] As Figures 3 to 5 shown, the optical lens includes an auxiliary barrel P0b, a barrel P0, four lenses and a plurality of spacer elements. The barrel P0 includes a retaining ring 20, a first lens E1, a first spacer element P1, a first auxiliary spacer element P1b, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3, and a fourth lens E4 arranged in sequence from the object side to the image side.

[0103] As Figure 2 shown, it is the structural schematic diagram of the optical lens of Embodiment 1-1. In this example, the image side surface of the retaining ring 20 is partially in contact with the object side surface S1 of the first lens, and the outer ring surface of the first lens E1 is partially in contact with the inner wall surface of the barrel P0. The object side surface of the first spacer element P1 is partially in contact with the image side surface S2 of the first lens, and the object side surface and the image side surface of the first auxiliary spacer element P1b are respectively partially in contact with the image side surface of the first spacer element P1 and the object side surface S3 of the second lens. The object side surface and the image side surface of the second spacer element P2 are respectively partially in contact with the image side surface S4 of the second lens and the object side surface S5 of the third lens. The object side surface and the image side surface of the third spacer element P3 are respectively partially in contact with the image side surface S6 of the third lens and the object side surface S7 of the fourth lens. The image side surface S8 of the fourth lens is partially in contact with the bearing surface of the barrel P0. The end surface of the barrel P0 closest to the object has a bearing groove 10, and a part of the auxiliary barrel P0b extends into the bearing groove 10 and is in contact with the barrel P0, and the two are connected by glue.

[0104] As Figure 3 shown, it is the structural schematic diagram of the optical lens of Embodiment 1-2. As Figure 4 shown, it is the structural schematic diagram of the optical lens of Embodiment 1-3. In Embodiment 1-2 and Embodiment 1-3, the bearing contact methods of each spacer element are similar to those in Embodiment 1-1, and the relevant descriptions in Embodiment 1-1 can be referred to, and will not be elaborated here.

[0105] In summary, the structural parameters of the optical lens of Example 1 under Embodiment 1-1, Embodiment 1-2, and Embodiment 1-3 are shown in Table 2. (Unit: mm)

[0106] Table 2

[0107]

[0108] In Embodiment 1, the first lens has a positive optical power. The object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is convex. The second lens has a positive optical power. The object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is concave. The third lens has a negative optical power. The object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave; the fourth lens has a positive optical power. The object side surface S7 of the fourth lens is convex, and the image side surface S8 of the fourth lens is convex. S9 to S12 in Table 3 below can be the surfaces of a filter or a protective glass, and no specific limitation is made here, while S13 is the imaging surface. S9 to S13 are not shown in the figure.

[0109] Table 3 shows the basic structural parameter table of the optical lens in Embodiment 1, where the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0110] Table 3

[0111]

[0112] In Embodiment 1, the object side surfaces and the image side surfaces of the second lens E2 to the fourth lens E4 are all aspherical surfaces. The surface profiles of the respective aspherical lenses can be defined by, but are not limited to, the following aspherical formula:

[0113] Formula (1)

[0114] Where x is the sagitta, the distance from the vertex of the aspherical surface when the aspherical surface is at a position with a height of h along the optical axis direction; c is the paraxial curvature of the aspherical surface, c = 1 / R, that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above; k is the conic coefficient; Ai is the correction coefficient of the i-th order of the aspherical surface. Table 4 below gives the higher-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, A30 that can be used for the aspherical surfaces S3 - S8 in Embodiment 1.

[0115] Table 4

[0116]

[0117] Figure 6 Shows the axial chromatic aberration curve of the optical lens in Embodiment 1, which represents the deviation of the convergence points of light rays with different wavelengths after passing through the optical lens. Figure 7 Shows the astigmatism curve of the optical lens in Embodiment 1, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 8 Shows the distortion curve of the optical lens in Embodiment 1, which represents the distortion magnitude values corresponding to different field angles.

[0118] According to Figures 6 to 8 it can be known that the optical lens given in the first embodiment can achieve good imaging quality.

[0119] The second embodiment

[0120] As Figures 9 to 14 shown, the optical lens of the second embodiment is described. Figure 9 The schematic structural diagram of the optical lens of Embodiment 2-1 is shown, Figure 10 The schematic structural diagram of the optical lens of Embodiment 2-2 is shown, Figure 11 The schematic structural diagram of the optical lens of Embodiment 2-3 is shown.

[0121] As Figures 9 to 14 shown, the optical lens includes an auxiliary barrel P0b, a barrel P0, four lenses and a plurality of spacer elements. The barrel P0 includes a retaining ring 20, a first lens E1, a first spacer element P1, a first auxiliary spacer element P1b, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3 and a fourth lens E4 arranged in sequence from the object side to the image side.

[0122] As Figure 9 shown, it is the schematic structural diagram of the optical lens of Embodiment 2-1. In this example, the image side surface of the retaining ring 20 is partially in contact with the object side surface S1 of the first lens, and the outer ring surface of the first lens E1 is partially in contact with the inner wall surface of the barrel P0. The object side surface of the first spacer element P1 is partially in contact with the image side surface S2 of the first lens, and the object side surface and the image side surface of the first auxiliary spacer element P1b are respectively partially in contact with the image side surface of the first spacer element P1 and the object side surface S3 of the second lens. The object side surface and the image side surface of the second spacer element P2 are respectively partially in contact with the image side surface S4 of the second lens and the object side surface S5 of the third lens. The object side surface and the image side surface of the third spacer element P3 are respectively partially in contact with the image side surface S6 of the third lens and the object side surface S7 of the fourth lens. The image side surface S8 of the fourth lens is partially in contact with the bearing surface of the barrel P0. The end face of the barrel P0 closest to the object has a bearing groove 10, and a part of the auxiliary barrel P0b extends into the bearing groove 10 and is in contact with the barrel P0, and the two are connected by glue.

[0123] As Figure 10 shown, it is the schematic structural diagram of the optical lens of Embodiment 2-2. In Embodiment 2-2, the bearing contact method of each spacer element is similar to that of Embodiment 2-1, and the relevant description in Embodiment 2-1 can be referred to, and details are not described here.

[0124] As Figure 11As shown, it is a schematic structural diagram of the optical lens of Embodiment 2-3. In Embodiment 2-3, the spacer element group further includes a second auxiliary spacer element P1c. The second auxiliary spacer element P1c is located between the first auxiliary spacer element P1b and the second lens E2. The object side and the image side of the second auxiliary spacer element P1c are respectively in partial contact with the image side of the first auxiliary spacer element P1b and the object side S3 of the second lens. The abutting and contacting manners of other spacer elements are similar to those in Embodiment 2-1, and reference can be made to the relevant descriptions in Embodiment 2-1, which will not be elaborated here.

[0125] In summary, the structural parameters of the optical lens of Embodiment 2 under Embodiments 2-1, 2-2, and 2-3 are shown in Table 5 below. (Unit: mm)

[0126] Table 5

[0127]

[0128] In Embodiment 2, the first lens has a positive optical power. The object side S1 of the first lens is a convex surface, and the image side S2 of the first lens is a concave surface. The second lens has a positive optical power. The object side S3 of the second lens is a convex surface, and the image side S4 of the second lens is a concave surface. The third lens has a negative optical power. The object side S5 of the third lens is a convex surface, and the image side S6 of the third lens is a concave surface; the fourth lens has a positive optical power. The object side S7 of the fourth lens is a convex surface, and the image side S8 of the fourth lens is a convex surface.

[0129] Table 6 shows the basic structural parameter table of the optical lens of Embodiment 2, where the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0130] Table 6

[0131]

[0132] Table 7 shows the high-order term coefficients that can be used for each aspherical mirror surface in Embodiment 2. Among them, each aspherical surface type can be defined by the formula (1) given in Embodiment 1 above. In this embodiment, the object side and the image side of the first lens to the fourth lens are all aspherical surfaces.

[0133] Table 7

[0134]

[0135] Figure 12 Shows the axial chromatic aberration curve of the optical lens of Embodiment 2, which represents the deviation of the focusing points of light rays of different wavelengths after passing through the optical lens. Figure 13 Shows the astigmatism curve of the optical lens of Embodiment 2, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 14The distortion curve of the optical lens of Embodiment 2 is shown, which represents the distortion magnitude values corresponding to different field angles of view.

[0136] According to Figures 12 to 14 it can be known that the optical lens given in Embodiment 2 can achieve good imaging quality.

[0137] Embodiment 3

[0138] As Figures 15 to 20 shown, the optical lens of Embodiment 3 is described. Figure 15 The structural schematic diagram of the optical lens of Embodiment 3-1 is shown, Figure 16 The structural schematic diagram of the optical lens of Embodiment 3-2 is shown, Figure 17 The structural schematic diagram of the optical lens of Embodiment 3-3 is shown.

[0139] As Figures 15 to 17 shown, the optical lens includes an auxiliary barrel P0b, a barrel P0, four lenses, and a plurality of spacer elements. The barrel P0 includes a retaining ring 20, a first lens E1, a first spacer element P1, a first auxiliary spacer element P1b, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3, and a fourth lens E4 arranged in sequence from the object side to the image side.

[0140] As Figure 15 shown, it is the structural schematic diagram of the optical lens of Embodiment 3-1. In this example, the image side surface of the retaining ring 20 is partially in contact with the object side surface S1 of the first lens, and the outer ring surface of the first lens E1 is partially in contact with the inner wall surface of the barrel P0. The object side surface of the first spacer element P1 is partially in contact with the image side surface S2 of the first lens, and the object side surface and the image side surface of the first auxiliary spacer element P1b are respectively partially in contact with the image side surface of the first spacer element P1 and the object side surface S3 of the second lens. The object side surface and the image side surface of the second spacer element P2 are respectively partially in contact with the image side surface S4 of the second lens and the object side surface S5 of the third lens. The object side surface and the image side surface of the third spacer element P3 are respectively partially in contact with the image side surface S6 of the third lens and the object side surface S7 of the fourth lens. The image side surface S8 of the fourth lens is partially in contact with the bearing surface of the barrel P0. The end face of the barrel P0 closest to the object has a bearing groove 10. A part of the auxiliary barrel P0b extends into the bearing groove 10 and is in contact with the barrel P0, and the two are connected by glue.

[0141] As Figure 16As shown, it is a schematic structural diagram of the optical lens of Embodiment 3-2. In Embodiment 3-2, the spacer element group further includes a second auxiliary spacer element P1c. The second auxiliary spacer element P1c is located between the first auxiliary spacer element P1b and the second lens E2. The object side and the image side of the second auxiliary spacer element P1c are respectively in partial contact with the image side of the first auxiliary spacer element P1b and the object side S3 of the second lens. The abutting and contacting manners of other spacer elements are similar to those in Embodiment 3-1. For relevant descriptions, reference can be made to Embodiment 3-1, and details will not be elaborated here.

[0142] As Figure 11 shown, it is a schematic structural diagram of the optical lens of Embodiment 3-3. In Embodiment 3-3, the abutting and contacting manners of each spacer element are similar to those in Embodiment 3-1. For relevant descriptions, reference can be made to Embodiment 3-1, and details will not be elaborated here.

[0143] In summary, the structural parameters of the optical lens in Embodiment 3 under Embodiment 3-1, Embodiment 3-2, and Embodiment 3-3 are shown in Table 8 below. (Unit: mm)

[0144] Table 8

[0145]

[0146] In Embodiment 3, the first lens has a positive optical power. The object side S1 of the first lens is a convex surface, and the image side S2 of the first lens is a flat surface. The second lens has a positive optical power. The object side S3 of the second lens is a convex surface, and the image side S4 of the second lens is a concave surface. The third lens has a negative optical power. The object side S5 of the third lens is a convex surface, and the image side S6 of the third lens is a concave surface; the fourth lens has a positive optical power. The object side S7 of the fourth lens is a concave surface, and the image side S8 of the fourth lens is a convex surface.

[0147] Table 9 shows the basic structural parameter table of the optical lens in Embodiment 3, where the unit of the radius of curvature and the thickness / distance is millimeter (mm).

[0148] Table 9

[0149]

[0150] Table 10 shows the high-order term coefficients that can be used for each aspherical mirror surface in Embodiment 3. Among them, each aspherical surface type can be defined by Formula (1) given in Embodiment 1 above. In this embodiment, the object side and the image side of the first lens to the fourth lens are all aspherical surfaces.

[0151] Table 10

[0152]

[0153] Figure 18Shows the axial chromatic aberration curve of the optical lens of Embodiment 3, which represents the deviation of the convergence points of light rays of different wavelengths after passing through the optical lens. Figure 19 Shows the astigmatism curve of the optical lens of Embodiment 3, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 20 Shows the distortion curve of the optical lens of Embodiment 3, which represents the distortion magnitude values corresponding to different field angles.

[0154] According to Figures 18 to 20 it can be known that the optical lens given in Embodiment 3 can achieve good imaging quality.

[0155] In summary, the optical lenses of Embodiments 1 to 3 respectively satisfy the relationships shown in Table 11.

[0156] Table 11

[0157]

[0158] Table 12 shows the effective focal lengths (unit: mm) of the respective lenses of the optical lenses of Embodiments 1 to 3.

[0159] Table 12

[0160]

[0161] This application also provides an imaging device, the electronic photosensitive element of which can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor element (CMOS). The imaging device can be an independent imaging device such as a digital camera, or an imaging module integrated on a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical lens described above.

[0162] Obviously, the above-described embodiments are only some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0163] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0164] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of this application are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here.

[0165] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An optical lens, characterized in that: The invention comprises a lens barrel and a lens group and a spacer element group assembled in the lens barrel. The lens group includes a first lens, a second lens, a third lens and a fourth lens in sequence from the object side to the image side along the optical axis; The spacer element group includes at least a first spacer element, the first spacer element is located between the first lens and the second lens and is in at least partial contact with the image side surface of the first lens; The height L of the lens barrel and the effective focal length f of the optical lens satisfy the following conditions: 0.27 <L / f<0.30; The refractive index N1 of the first lens and the effective focal length f1 of the first lens satisfy: 17.22 mm <N1×f1<18.96mm; The distance EP01 between the object side end face of the lens barrel and the object side face of the first spacing element along the optical axis extension direction and the edge thickness ET1 of the non-effective diameter area of ​​the first lens satisfy: 1.69 <EP01 / ET1<2.66; The inner diameter d0s of the object side end surface of the lens barrel and the inner diameter d1s of the object side surface of the first spacing element satisfy: 1.18 <d0s / d1s<1.25。 2. The optical lens according to claim 1, characterized in that: The on-axis distance SAG11 between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the non-effective diameter area of ​​the object side surface of the first lens and the outer diameter D1s of the object side surface of the first spacer element satisfy: 0.09<|SAG11| / D1s <0.

12.

3. The optical lens according to claim 1, characterized in that: The center thickness CT1 of the first lens, the air gap T12 between the first lens and the second lens on the optical axis, and the spacing distance EP01 between the object side end face of the lens barrel and the object side face of the first spacing element along the extension direction of the optical axis satisfy the following: 1.29<(CT1+T12) / EP01<1.

72.

4. The optical lens according to claim 1, characterized in that: The curvature radius R1 of the object side surface of the first lens and the outer diameter D0s of the object side end surface of the lens barrel satisfy: 0.95 <R1 / D0s<1.19。 5. The optical lens according to claim 1, characterized in that: The outer diameter D1s of the object side surface of the first spacer element, the distance EP01 between the object side end surface of the lens barrel and the object side surface of the first spacer element along the optical axis extension direction, and the center thickness CT1 of the first lens satisfy: 8.96 mm <D1s / (EP01 / CT1)<10.89mm。 6. The optical lens according to claim 1, characterized in that: The air gap T12 between the first lens and the second lens on the optical axis and the sum ΣAT of the air gaps between two adjacent lenses from the first lens to the fourth lens satisfy the following: 0.05 <T12 / ∑AT<0.17。 7. The optical lens according to claim 1, characterized in that: The effective focal length f1 of the first lens, the inner diameter d0s of the object side end surface of the lens barrel and the inner diameter d1s of the object side surface of the first spacing element satisfy: 5.65 <f1 / (d0s-d1s)<7.65。 8. The optical lens according to any one of claims 1 to 7, characterized in that: The spacer element group further includes a first auxiliary spacer element, which is located between the first spacer element and the second lens and at least partially contacts the image side surface of the first spacer element, and the outer diameter D1bm of the image side surface of the first auxiliary spacer element and the inner diameter d1bm of the image side surface of the first auxiliary spacer element satisfy the following relationship: 1.12 <D1bm / d1bm<1.30。 9. The optical lens according to any one of claims 1 to 7, characterized in that: The spacer element group also includes a second spacer element, which is located between the second lens and the third lens, and the second spacer element is in contact with the image side portion of the second lens, and the maximum thickness CP1 of the first spacer element in the extension direction of the optical axis, the spacing distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element along the extension direction of the optical axis, and the center thickness CT2 of the first lens satisfy the following: 1.38<(CP1+EP12) / CT2<1.

65.

10. The optical lens according to claim 9, characterized in that: A curvature radius R3 of the object-side surface of the second lens, a curvature radius R4 of the image-side surface of the second lens, and an inner diameter d2s of the object-side surface of the second spacer element satisfy the following relationship: 2.49<(R3+R4) / d2s<9.

56.

11. The optical lens according to claim 9, characterized in that: The combined focal length f12 of the first lens and the second lens, the maximum thickness CP1 of the first spacing element in the direction of extension of the optical axis, and the spacing distance EP12 between the image side surface of the first spacing element and the object side surface of the second spacing element in the direction of extension of the optical axis satisfy: 4.47 <f12 / (CP1+EP12)<5.49。 12. The optical lens according to any one of claims 1 to 7, characterized in that: The spacer element group further includes a second spacer element and a third spacer element, the second spacer element is located between the second lens and the third lens and contacts the image side surface of the second lens, the third spacer element is located between the third lens and the fourth lens and contacts the image side surface of the third lens, the minimum inner diameter of the first spacer element is greater than the minimum inner diameter of the second spacer element, and the minimum inner diameter of the second spacer element is greater than the minimum inner diameter of the third spacer element, The inner diameter d1s of the object side surface of the first spacing element and the inner diameter d2s of the object side surface of the second spacing element satisfy: 0.77 <d2s / d1s<0.84; The inner diameter d3s of the object side surface of the third spacing element and the inner diameter d2s of the object side surface of the second spacing element satisfy: 0.85 <d3s / d2s<0.89; The inner diameter d1m of the image side surface of the first spacing element and the inner diameter d2m of the image side surface of the second spacing element satisfy: 0.81 <d2m / d1m<0.90; The inner diameter d3m of the image side surface of the third spacing element and the inner diameter d2m of the image side surface of the second spacing element satisfy: 0.86 <d3m / d2m<0.89。 13. The optical lens according to any one of claims 1 to 7, characterized in that: The optical lens also includes an auxiliary lens barrel, which is located on the object side of the lens barrel, and is connected to the lens barrel. The height L of the lens barrel, the height Lb of the auxiliary lens barrel, the outer diameter D0bm of the image side end surface of the auxiliary lens barrel, and the inner diameter d0bs of the object side end surface of the auxiliary lens barrel satisfy the following conditions: 1.98 mm -1 <L / Lb / (D0bm-d0bs)<2.34mm -1 .

14. The optical lens according to claim 13, characterized in that: The inner diameter d0bs of the object side end surface of the auxiliary lens barrel and the maximum effective radius DT11 of the object side surface of the first lens satisfy the following relationship: 1.96 <d0bs / DT11<2.04。 15. The optical lens according to any one of claims 1 to 7, characterized in that: The first lens has positive optical power, the second lens has positive optical power, the third lens has negative optical power, and the fourth lens has positive optical power.

16. The optical lens according to any one of claims 1 to 7, characterized in that: The object side surface of the first lens is a convex 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 object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; The image side surface of the fourth lens is a convex surface.

Images