Optical lens

Abstract

The application provides an optical lens. The optical lens comprises a lens barrel, a lens set and a plurality of spacer elements accommodated in the lens barrel; the lens set comprises, in sequence from an object side to an image side along an optical axis, a first lens with positive refractive power, a second lens with positive refractive power, a third lens with positive refractive power and a fourth lens with refractive power, the object side of the first lens is concave and the image side is convex, the object side of the second lens is convex and the image side is concave, the image side of the third lens is convex, the object side of the fourth lens is convex and the image side is concave; the plurality of spacer elements comprises a first spacer element and a second spacer element; the optical lens satisfies: 1.35 < d0s / EPD < 1.60; -3.10 < f1 / (R1+R2) < -1.30; and 1.15 < (d0s-d1s) / EP01 < 2.00.

Description

Technical Field

[0001] This application relates to the technical field of optical devices, and particularly to an optical lens. Background Art

[0002] Among the core technologies of autonomous driving, the environmental perception module is one of the most important technologies. As one of the main solutions for the environmental perception module, lidar has the advantages of working all day long, being insensitive to ambient light, and having high ranging accuracy. Therefore, it has great advantages in autonomous driving and broad application prospects. As the lens of the lidar receiving end, compared with lenses in other usage scenarios, while ensuring the imaging quality of the lens, higher requirements are imposed on the reliability of the lens. Such lenses need to simultaneously meet requirements such as low cost, small weight, clear imaging, and assembly stability.

[0003] In traditional optical lens design, increasing the entrance pupil diameter (EPD) is usually adopted to improve the light transmission, and a lens with a larger radius of curvature is used to achieve the effect of improving the lens compactness. However, for the former, the inner diameter of the object side of the lens barrel needs to be enlarged (such as a flared design), but excessive enlargement will lead to risks of lens positioning deviation and light path blockage. For the latter, if the ratio of the radius of curvature to the focal length gets out of control, it will exacerbate the partial deviation of the lens structure, causing the optical center to deviate from the mechanical center, and even possibly resulting in interference between the lens and the spacer element or the inner wall of the lens barrel. Summary of the Invention

[0004] One advantage of this application is to provide an optical lens that can solve the adverse effects on the lens stability caused by increasing the aperture and reducing the volume of the optical lens at the lidar receiving end.

[0005] To this end, this application provides an optical lens, including a lens barrel and a lens group and a plurality of spacer elements accommodated within the lens barrel; the lens group includes, arranged in sequence along the optical axis from the object side to the image side: a first lens with positive optical power, a second lens with positive optical power, a third lens with positive optical power, and a fourth lens with optical power. The object side of the first lens is concave and the image side is convex. The object side of the second lens is convex and the image side is concave. The image side of the third lens is convex. The object side of the fourth lens is convex and the image side is concave. The plurality of spacer elements includes a first spacer element placed on the image side of the first lens and in contact with the image side of the first lens, and a second spacer element placed on the image side of the second lens and in contact with the image side of the second lens. The optical lens satisfies: 1.35 < d0s / EPD < 1.60; -3.10 < f1 / (R1 + R2) < -1.30; and 1.15 < (d0s - d1s) / EP01 < 2.00;

[0006] Wherein, d0s is the inner diameter of the object side surface of the lens barrel; EPD is the entrance pupil diameter of the optical lens; f1 is the effective focal length of the first lens; R1 is the radius of curvature of the object side surface of the first lens; R2 is the radius of curvature of the image side surface of the first lens; d1s is the inner diameter of the object side surface of the first spacer element; EP01 is the distance between the object side surface of the lens barrel and the object side surface of the first spacer element along the optical axis.

[0007] In some embodiments of this application, the optical lens satisfies: 1.45 <EP01 / (SAG11+SAG12) <1.80;

[0008] Wherein, EP01 is the distance between the object side of the lens barrel and the object side of the first spacer element along the optical axis, SAG11 is the axial displacement between the intersection of the object side of the first lens and the optical axis and the vertex of the effective radius of the object side of the first lens, and SAG12 is the axial displacement between the intersection of the image side of the first lens and the optical axis and the vertex of the effective radius of the image side of the first lens.

[0009] In some embodiments of this application, the optical lens satisfies: 0.20 < (d0m - d0s) / f < 1.00;

[0010] Where f is the effective focal length of the optical lens, d0s is the inner diameter of the object side of the lens barrel, and d0m is the inner diameter of the image side of the lens barrel.

[0011] In some embodiments of this application, the optical lens satisfies: 5.45 <d0s / CT1<7.00;

[0012] Wherein, d0s is the inner diameter of the object side of the lens barrel, and CT1 is the center thickness of the first lens.

[0013] In some embodiments of this application, the optical lens satisfies: 2.75 <f1 / (EP01×N1×10)<4.65;

[0014] Wherein, f1 is the effective focal length of the first lens, EP01 is the distance between the object side of the lens barrel and the object side of the first spacer element along the optical axis, and N1 is the refractive index of the first lens.

[0015] In some embodiments of this application, the optical lens satisfies: 0.00≤CP1 / (D1s-d1s)<0.30;

[0016] Wherein, CP1 is the maximum thickness of the first spacer element along the optical axis, D1s is the outer diameter of the object side of the first spacer element, and d1s is the inner diameter of the object side of the first spacer element.

[0017] In some embodiments of this application, the plurality of spacers further includes a first auxiliary spacer element disposed between the first lens and the second lens and in contact with the image side of the first spacer element, wherein the optical lens satisfies: 0.00 < ∑CP1 / (CT1+CT2) < 0.45;

[0018] Wherein, ∑CP1 is the sum of the maximum thicknesses of the first spacer element and the first auxiliary spacer element along the optical axis, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

[0019] In some embodiments of this application, the optical lens satisfies: 1.90 <d1m / DT21<2.25;

[0020] Wherein, d1m is the inner diameter of the image side of the first spacer element, and DT21 is the maximum effective radius of the object side of the second lens.

[0021] In some embodiments of this application, the optical lens satisfies:

[0022] 0.50 <EP12 / R3<1.00;

[0023] Wherein, EP12 is the distance between the image side of the first spacer element and the object side of the second spacer element along the optical axis, and R3 is the radius of curvature of the object side of the second lens.

[0024] In some embodiments of this application, the optical lens satisfies: 2.85 ≤ L / EP02 < 4.10;

[0025] Wherein, L is the maximum height of the lens barrel, and EP02 is the distance between the object side of the lens barrel and the object side of the second spacer element along the optical axis.

[0026] In some embodiments of this application, the optical lens satisfies: 3.45 <f12 / (d1s+d2s)<5.20;

[0027] Wherein, f12 is the combined focal length of the first lens and the second lens, d1s is the inner diameter of the object side surface of the first spacer element, and d2s is the inner diameter of the object side surface of the second spacer element.

[0028] In some embodiments of this application, the optical lens satisfies: 0.40 < (D²s - d²s) / d²s < 0.95;

[0029] Wherein, D2s is the outer diameter of the object side of the second spacer element, and d2s is the inner diameter of the object side of the second spacer element.

[0030] In some embodiments of the present application, the optical lens satisfies: 0.45 < L / (D0m + D0s) < 0.60;

[0031] Where, L is the maximum height of the lens barrel, D0m is the outer diameter of the image side of the lens barrel, and D0s is the outer diameter of the object side of the lens barrel.

[0032] In some embodiments of the present application, the optical lens satisfies: 3.05 ≤ d0m / (f × tan(FOV / 2)) < 4.00;

[0033] Where, d0m is the inner diameter of the image side of the lens barrel, f is the effective focal length of the optical lens, and FOV is the maximum field angle of the optical lens.

[0034] In summary, for the optical lens of the present application, by controlling the ratio conditions 1.35 < d0s / EPD < 1.60 and -3.10 < f1 / (R1 + R2) < -1.30 within a reasonable range, the relationship between the inner diameter of the object side of the lens barrel (flare design) and the entrance pupil diameter is effectively balanced, and the effective focal length and curvature radius of the first lens are reasonably restricted. While meeting the requirements of large light transmission and high aperture of the lens, aberration correction is carried out, ensuring the imaging quality of the lens. However, the optical lens that meets the above two conditional formulas will bring the risk of potential decline in the stability of lens support and positioning and the structural strength of the front end of the lens barrel. Especially when subjected to assembly pressure or environmental force, the front end of the lens barrel is prone to deformation, increasing the lens assembly risk. In response, in the present application, by restricting 1.15 < (d0s - d1s) / EP01 < 2.00, the front end size of the lens barrel is within a reasonable range, enhancing the structural stability of the lens barrel while ensuring no occlusion of the incident light of the system. Thus, when承受组装压力时, the deformation amount of the front end of the lens barrel can be effectively restricted within the safety threshold, ensuring the safety and reliability of the assembly process and excluding the risk of abrasion of the front lens (i.e., the first lens). BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1A is a schematic diagram of partial structural parameters of an optical lens according to an embodiment of the present application;

[0036] Figure 1B is a schematic diagram of partial structural parameters of an optical lens according to an embodiment of the present application;

[0037] Figure 2 is a schematic diagram of the structure of an optical lens according to Embodiment 1 of the present application;

[0038] Figure 3 is a schematic diagram of the structure of an optical lens according to Embodiment 2 of the present application;

[0039] Figure 4This is a schematic diagram of the structure of an optical lens according to Embodiment 3 of this application;

[0040] Figure 5A A schematic diagram of the on-axis chromatic aberration curves of the optical lenses according to the above-described Embodiment 1, Embodiment 2 and Embodiment 3 of this application is shown;

[0041] Figure 5B A schematic diagram of the astigmatism curves of the optical lenses according to Embodiment 1, Embodiment 2 and Embodiment 3 of this application is shown.

[0042] Figure 5C The diagram shows the distortion curves of the optical lenses according to the above-described Embodiment 1, Embodiment 2, and Embodiment 3 of this application;

[0043] Figure 5D A schematic diagram of the magnification chromatic aberration curves of the optical lenses according to the above-described Embodiment 1, Embodiment 2, and Embodiment 3 of this application is shown.

[0044] Figure 6 This is a schematic diagram of the structure of an optical lens according to Embodiment 4 of this application;

[0045] Figure 7 This is a schematic diagram of the structure of an optical lens according to Embodiment 5 of this application;

[0046] Figure 8 This is a schematic diagram of the structure of an optical lens according to Embodiment Six of this application;

[0047] Figure 9A A schematic diagram of the on-axis chromatic aberration curves of the optical lenses according to Embodiments 4, 5 and 6 of this application is shown.

[0048] Figure 9B A schematic diagram of the astigmatism curves of the optical lenses according to Embodiments 4, 5 and 6 of this application is shown.

[0049] Figure 9C The diagram shows the distortion curves of the optical lenses according to Embodiments 4, 5 and 6 of this application.

[0050] Figure 9D A schematic diagram of the magnification chromatic aberration curves of the optical lenses of Embodiments 4, 5, and 6 according to this application is shown.

[0051] Figure 10 This is a schematic diagram of the structure of an optical lens according to Embodiment Seven of this application;

[0052] Figure 11This is a schematic diagram of the structure of an optical lens according to Embodiment 8 of this application;

[0053] Figure 12 This is a schematic diagram of the structure of an optical lens according to Embodiment Nine of this application;

[0054] Figure 13A A schematic diagram of the on-axis chromatic aberration curves of the optical lenses of Embodiments 7, 8, and 9 according to this application is shown.

[0055] Figure 13B A schematic diagram of the astigmatism curves of the optical lenses according to Embodiments 7, 8 and 9 of this application is shown.

[0056] Figure 13C A schematic diagram of the distortion curves of the optical lenses according to Embodiments 7, 8 and 9 of this application is shown.

[0057] Figure 13D A schematic diagram of the magnification chromatic aberration curves of the optical lenses of Embodiments 7, 8, and 9 according to this application is shown.

[0058] Figure 14A The optical path diagram is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 1.68;

[0059] Figure 14B The optical path diagram is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 1.00;

[0060] Figure 14C The optical path diagram is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 2.78;

[0061] Figure 15A A schematic diagram of the lens barrel front deformation is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 1.68;

[0062] Figure 15B A schematic diagram of the lens barrel front deformation is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 1.00;

[0063] Figure 15C A schematic diagram of the lens barrel front deformation is shown when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 2.78. Detailed Implementation

[0064] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this 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.

[0065] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply 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.

[0066] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0067] In this paper, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity 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 location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface shape in the paraxial region can be determined according to methods commonly used in the art, such as using the sign of the R value (R refers to the radius of curvature of the paraxial region) to determine concavity or convexity. In this paper, the surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens. For the object-side surface, when the R value is positive, it is determined to be convex, and when the R value is negative, it is determined to be concave; for the image-side surface, when the R value is positive, it is determined to be concave, and when the R value is negative, it is determined to be convex.

[0068] It should also be understood that the terms "comprising," "including," "having," "containing," 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. Furthermore, when a statement such as "at least one of" appears after a list of listed features, it modifies the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0069] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0070] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. The following embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this application. It should be pointed out that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0071] According to one aspect of this application, such as Figure 1A as well as Figure 1B As shown, one embodiment of this application proposes an optical lens, which may include a lens barrel and a lens group and a plurality of spacer elements housed within the lens barrel; the lens group includes a first lens having positive optical power, a second lens having positive optical power, a third lens having positive optical power, and a fourth lens having optical power arranged sequentially along the optical axis from the object-side surface to the image-side surface, wherein the object-side surface of the first lens is concave and the image-side surface is convex, the object-side surface of the second lens is convex and the image-side surface is concave, the image-side surface of the third lens is convex, and the object-side surface of the fourth lens is convex and the image-side surface is concave; the plurality of spacer elements include a first spacer element placed on and in contact with the image-side surface of the first lens and a second spacer element placed on and in contact with the image-side surface of the second lens.

[0072] Specifically, the optical lens satisfies: 1.35 < d0s / EPD < 1.60; -3.10 < f1 / (R1+R2) < -1.30; and 1.15 < (d0s-d1s) / EP01 < 2.00; where, d0s is the inner diameter of the object side of the lens barrel; EPD is the entrance pupil diameter of the optical lens; f1 is the effective focal length of the first lens; R1 is the curvature radius of the object side of the first lens; R2 is the curvature radius of the image side of the first lens; d1s is the inner diameter of the object side of the first spacer; and EP01 is the distance between the object side of the lens barrel and the object side of the first spacer along the optical axis direction.

[0073] It should be noted that in the above embodiments of the present application, by controlling the ratio conditions 1.35 < d0s / EPD < 1.60 and -3.10 < f1 / (R1+R2) < -1.30 within a reasonable range, the relationship between the inner diameter of the object side of the lens barrel (flare design) and the entrance pupil diameter is effectively balanced, and the effective focal length and curvature radius of the first lens are reasonably constrained. While satisfying the large light transmission and high aperture requirements of the lens, aberration correction is performed, ensuring the imaging quality of the lens. However, an optical lens that satisfies the above two conditional formulas may bring risks of potential decline in the stability of lens support and positioning and the structural strength of the front end of the lens barrel. Especially when subjected to assembly pressure or environmental forces, the front end of the lens barrel is prone to deformation, increasing the lens assembly risk. In response, in this application, by restricting 1.15 < (d0s-d1s) / EP01 < 2.00, the front end size of the lens barrel is within a reasonable range, enhancing the structural stability of the lens barrel while ensuring that the incident light of the system is unobstructed. Thus, when承受 assembly pressure, the deformation amount of the front end of the lens barrel can be effectively restricted within the safety threshold, ensuring the safety and reliability of the assembly process and excluding the risk of abrasion of the front lens (i.e., the first lens).

[0074] Exemplarily, Figure 14A and Figure 15A respectively show the optical path schematic diagram and the deformation schematic diagram of the front end of the lens barrel when the optical lens satisfies d0s / EPD = 1.43; f1 / (R1+R2) = -1.34; and (d0s-d1s) / EP01 = 1.68; Figure 14B and Figure 15B respectively show the optical path schematic diagram and the deformation schematic diagram of the front end of the lens barrel when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 1.00; Figure 14C and Figure 15C respectively show the optical path schematic diagram and the deformation schematic diagram of the front end of the lens barrel when the optical lens satisfies d0s / EPD = 1.43, f1 / (R1+R2) = -1.34 and (d0s-d1s) / EP01 = 2.78.

[0075] As can be easily seen from the diagram: Figure 14A and Figure 15A As shown, when the relation d0s / EPD is greater than 1.35 and less than 1.60, the relation f1 / (R1+R2) is greater than -3.10 and less than -1.30, and (d0s-d1s) / EP01 is greater than 1.15 and less than 2.00, there is no light obstruction, the thickness of the front end of the microscope tube is consistent with that of the microscope tube, and the deformation of the front end of the microscope tube is 1.36μm when subjected to an assembly pressure of 20N, which meets the requirements (standard within 3μm).

[0076] like Figure 14B and Figure 15B As shown, when the relation d0s / EPD is greater than 1.35 and less than 1.60, the relation f1 / (R1+R2) is greater than -3.10 and less than -1.30, and (d0s-d1s) / EP01 is less than or equal to 1.15, the front end of the lens barrel is too thick and the flare angle is too small. The designed optical path is blocked by the flare of the lens barrel. When subjected to an assembly pressure of 20N, the front end of the lens barrel will be misaligned, with a deformation of 4.87μm, which exceeds the requirement (standard within 3μm), and there is a risk of assembly deformation. In other words, when the value of (d0s-d1s) / EP01 exceeds the lower limit of the condition, it will lead to the front end of the lens barrel being too thick and the flare angle being insufficient, resulting in the problem of the designed optical path being blocked by the lens barrel. At the same time, the deformation of the front end of the lens barrel is large and exceeds the standard under assembly pressure, and the risk of assembly instability is high.

[0077] like Figure 14C and Figure 15C As shown, when the relation d0s / EPD is greater than 1.35 and less than 1.60, the relation f1 / (R1+R2) is greater than -3.10 and less than -1.30, and (d0s-d1s) / EP01 is greater than or equal to 2.00, the light is unobstructed, the lens front protrudes, the first lens extends beyond the top surface of the lens barrel, the lens is easily scratched, and the support area at the front of the lens barrel is relatively thin. Under an assembly pressure of 20N, the deformation of the front of the lens barrel is 7.84μm, which exceeds the requirement (standard within 3μm), and the risk of assembly deformation is high. In other words, when the value of (d0s-d1s) / EP01 exceeds the upper limit of the conditional expression, it will cause the front of the lens barrel to be too thin and / or the relative position of the lens to protrude, causing the first lens to easily protrude from the end face of the lens barrel, thereby increasing the risk of scratching. Moreover, under the same assembly pressure, the deformation of the front of the lens barrel is larger, and the risk of assembly deformation and structural failure is higher.

[0078] Preferably, the optical lens satisfies: 1.39≤d0s / EPD≤1.59; -3.06≤f1 / (R1+R2) ≤-1.34; and 1.18≤(d0s-d1s) / EP01≤1.99.

[0079] According to some embodiments of the present application, the optical lens satisfies: 1.45 < EP01 / (SAG11 + SAG12) < 1.80; where EP01 is the distance between the object side of the lens barrel and the object side of the first spacer element in the optical axis direction, SAG11 is the axial displacement between the intersection point of the object side of the first lens and the optical axis and the vertex of the effective radius of the object side of the first lens, and SAG12 is the axial displacement between the intersection point of the image side of the first lens and the optical axis and the vertex of the effective radius of the image side of the first lens.

[0080] In this way, by controlling the ratio range of EP01 / (SAG11 + SAG12), the thickness ratio of the first lens can be kept within a reasonable range, optimizing the thickness ratio of the lens, ensuring the structural stability and reliability, and avoiding the situation of poor molding and unstable assembly; it can be understood that if the ratio is too small, the edge thickness of the first lens will be relatively thin, and there is a risk of distorted molding surface, while if the ratio is too large, the axial positioning stability of the first lens will be insufficient due to the excessive thickness in the edge area of the lens, that is to say, there is a risk of unstable assembly of the first lens.

[0081] Preferably, the optical lens satisfies: 1.47 ≤ EP01 / (SAG11 + SAG12) ≤ 1.77.

[0082] According to some embodiments of the present application, the optical lens satisfies: 0.20 < (d0m - d0s) / f < 1.00; where f is the effective focal length of the optical lens, d0s is the inner diameter of the object side of the lens barrel, and d0m is the inner diameter of the image side of the lens barrel.

[0083] In this way, by limiting the range of (d0m - d0s) / f, the proportional relationship between the inner diameter difference between the object side and the image side of the lens barrel and the system focal length is effectively constrained, ensuring that the vertical height difference (step difference) between the first lens and the fourth lens is within a reasonable and controllable range, so as to realize the control of the step difference of the lens in the vertical direction; in addition, it can also directly suppress the problem of out-of-control assembly step difference caused by the excessive vertical step difference between the first lens and the fourth lens, eliminate the hidden dangers of lens offset, stress concentration or optical path misalignment caused thereby, and thus avoid the risk of mechanical interference.

[0084] Preferably, the optical lens satisfies: 0.21 ≤ (d0m - d0s) / f ≤ 0.96.

[0085] According to some embodiments of the present application, the optical lens satisfies: 5.45 < d0s / CT1 < 7.00; where d0s is the inner diameter of the object side of the lens barrel and CT1 is the center thickness of the first lens.

[0086] In this way, by limiting the range of d0s / CT1, the ratio of the inner diameter of the object side of the lens barrel to the central thickness of the first lens is controlled, so that a balance is formed between unobstructed light transmission and structural strength of the flare, avoiding problems such as imaging defects or lifespan attenuation caused by size fragmentation in traditional designs, and meeting the durability requirements of lidar; specifically, if the ratio is too large, the radial width at the front end of the lens barrel (i.e., the stress area) is too small, and there is not enough structural strength to resist the assembly pressure. If the ratio is too small, the flare angle of the lens barrel is too small, resulting in edge light blocking, and then the integrity of full-field light transmission cannot be guaranteed.

[0087] Preferably, the optical lens satisfies: 5.46 ≤ d0s / CT1 ≤ 6.98.

[0088] According to some embodiments of the present application, the optical lens satisfies: 2.75 < f1 / (EP01 × N1 × 10) < 4.65; where f1 is the effective focal length of the first lens, EP01 is the distance between the object side of the lens barrel and the object side of the first spacer along the optical axis direction, and N1 is the refractive index of the first lens.

[0089] In this way, by limiting f1 / (EP01 × N1 × 10) within a suitable range, the cooperative relationship between the effective focal length of the first lens, the axial distance between the lens barrel and the first spacer, and the refractive index of the first lens can be constrained, thereby effectively optimizing the incident angle of marginal field light passing through the first lens, significantly reducing the tolerance sensitivity of the optical lens, and at the same time ensuring the compactness and machinability of the head structure of the optical lens.

[0090] Preferably, the optical lens satisfies: 2.77 ≤ f1 / (EP01 × N1 × 10) ≤ 4.61.

[0091] According to some embodiments of the present application, the optical lens satisfies: 0.00 ≤ CP1 / (D1s-d1s) < 0.30; where CP1 is the maximum thickness of the first spacer along the optical axis direction, D1s is the outer diameter of the object side of the first spacer, and d1s is the inner diameter of the object side of the first spacer.

[0092] In this way, by controlling the ratio range of CP1 / (D1s-d1s), the radial width of the first spacer is made larger than the axial thickness, that is, the aspect ratio of the first spacer is relatively large, which is helpful for the first spacer to effectively block stray light and avoid stray light problems caused by poor machining of the inner diameter of the injection molded part.

[0093] Preferably, the optical lens satisfies: 0.00 ≤ CP1 / (D1s-d1s) ≤ 0.28.

[0094] According to some embodiments of the present application, the plurality of spacer elements further includes a first auxiliary spacer element disposed between the first lens and the second lens and in contact with the image side surface of the first spacer element, and the optical lens satisfies: 0.00 < ∑CP1 / (CT1 + CT2) < 0.45; where ∑CP1 is the sum of the maximum thicknesses of the first spacer element and the first auxiliary spacer element along the optical axis direction, CT1 is the central thickness of the first lens, and CT2 is the central thickness of the second lens.

[0095] In this way, by limiting the range of ∑CP1 / (CT1 + CT2), this ratio can control the central thickness dimensions of the first lens and the second lens, avoiding the situation of poor molding of the injection-molded lens; in addition, this ratio can not only limit the minimum thickness of the first spacer element and the first auxiliary spacer element, thus ensuring that the structural strength of both meets the requirements, but also can avoid squeezing the lens due to the excessive thickness of the first spacer element.

[0096] Preferably, the optical lens satisfies: 0.01 ≤ ∑CP1 / (CT1 + CT2) ≤ 0.42.

[0097] According to some embodiments of the present application, the optical lens satisfies: 1.90 < d1m / DT21 < 2.25; where d1m is the inner diameter of the image side surface of the first spacer element, and DT21 is the maximum effective radius of the object side surface of the second lens.

[0098] In this way, by controlling the ratio of d1m / DT21, the ratio of the inner diameter of the image side surface of the first spacer element to the maximum effective radius of the object side surface of the second lens can be controlled within the above range, ensuring that the inner diameter size of the first spacer element is reasonably constrained, avoiding the situation where stray light generated at the edge of the effective diameter of the second lens and adjacent structures passes through the first spacer element, thereby reducing the negative impact of stray light on imaging and improving the reliability of the overall imaging quality of the lens.

[0099] Preferably, the optical lens satisfies: 1.93 ≤ d1m / DT21 ≤ 2.22.

[0100] According to some embodiments of the present application, the optical lens satisfies: 0.50 < EP12 / R3 < 1.00; where EP12 is the spacing between the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis direction, and R3 is the curvature radius of the object side surface of the second lens.

[0101] In this way, by controlling the proportional relationship between the axial spacing of the first and second spacer elements and the curvature radius of the object side surface of the second lens, the risk of increased sag caused by excessive curvature of the object side surface of the second lens is effectively suppressed, keeping its surface shape relatively flat, avoiding the problem of excessive deviation (astigmatism) of the lens edge surface shape caused by excessive curvature during the lens molding process, thereby ensuring the optical surface accuracy and imaging performance stability of the second lens.

[0102] Preferably, the optical lens satisfies: 0.53 ≤ EP12 / R3 ≤ 0.96.

[0103] According to some embodiments of the present application, the optical lens satisfies: 2.85 ≤ L / EP02 < 4.10; where L is the maximum height of the lens barrel, and EP02 is the distance between the object side surface of the lens barrel and the object side surface of the second spacer element in the optical axis direction.

[0104] In this way, by controlling the ratio of L / EP02, the compatibility and assembly reliability of the lens barrel size can be ensured; specifically, by controlling the ratio of the lens barrel height to the axial distance from the object side surface of the lens barrel to the object side surface of the second spacer element within the above range, the lens barrel height is constrained within the optimal size range. This design effectively avoids the risk of module space interference caused by an overly large lens barrel height, and at the same time eliminates the problem of insufficient positioning stability caused by an overly small height, thereby significantly improving the compatibility and success rate of reliable assembly between the optical lens and the external module.

[0105] Preferably, the optical lens satisfies: 2.85 ≤ L / EP02 ≤ 4.08.

[0106] According to some embodiments of the present application, the optical lens satisfies: 3.45 < f12 / (d1s + d2s) < 5.20; where f12 is the combined focal length of the first lens and the second lens, d1s is the inner diameter of the object side surface of the first spacer element, and d2s is the inner diameter of the object side surface of the second spacer element.

[0107] In this way, by limiting the ratio of f12 / (d1s + d2s), the incidence of stray light can be suppressed; it can be understood that this ratio constraint enables the inner diameter dimensions of the object side surfaces of the first spacer element and the second spacer element to obtain an optimized design that matches the combined focal length of the first lens and the second lens. This design effectively controls the light passing aperture size between the first lens and the second lens, strictly limits the inner diameters of the first spacer element and the second spacer element (especially the aperture pointing to the object side surface) within a reasonable range, reduces the interference of stray light that may enter from the structural gaps or edges of the first spacer element and the second spacer element, and significantly improves the signal-to-noise ratio and detection accuracy of system imaging.

[0108] Preferably, the optical lens satisfies: 3.49 ≤ f12 / (d1s + d2s) ≤ 5.17.

[0109] According to some embodiments of the present application, the optical lens satisfies: 0.40 < (D2s - d2s) / d2s < 0.95; where D2s is the outer diameter of the object side surface of the second spacer element, and d2s is the inner diameter of the object side surface of the second spacer element.

[0110] In this way, by constraining (D2s - d2s) / d2s, it is possible to control the width of the second spacer element within a reasonable range by controlling the outer diameter and inner diameter of the side surface of the second spacer element, so as to ensure that the second spacer element has sufficient structural strength while strictly constraining its radial dimension within a reasonable range, effectively avoiding the problem of overall radial dimension expansion of the lens caused by an excessively large outer diameter of the second spacer element, which is beneficial to maintaining the miniaturization and compact design goals of the lens.

[0111] Preferably, the optical lens satisfies: 0.44 ≤ (D2s - d2s) / d2s ≤ 0.94.

[0112] According to some embodiments of the present application, the optical lens satisfies: 0.45 < L / (D0m + D0s) < 0.60; where L is the maximum height of the lens barrel, D0m is the outer diameter of the image side of the lens barrel, and D0s is the outer diameter of the object side of the lens barrel.

[0113] In this way, by limiting the ratio range of L / (D0m + D0s), the overall configuration and space occupancy of the lens can be optimized. This ratio regulates the relationship between the total height of the lens and the outer diameters of the object side and image side of the lens barrel, so as to achieve a balance between the axial height and radial dimension of the lens barrel, avoiding the problem of axial space redundancy of the lens caused by an excessively large height of the lens barrel, and at the same time suppressing the problem of overall radial dimension expansion caused by an excessive increase in the outer diameter of the object side or image side of the lens barrel, improving the structural compactness of the optical lens of the present application and optimizing its space occupancy efficiency in the system.

[0114] Preferably, the optical lens satisfies: 0.48 ≤ L / (D0m + D0s) ≤ 0.57.

[0115] According to some embodiments of the present application, the optical lens satisfies: 3.05 ≤ d0m / (f × tan(FOV / 2)) < 4.00; where d0m is the inner diameter of the image side of the lens barrel, f is the effective focal length of the optical lens, and FOV is the maximum field angle of the optical lens.

[0116] In this way, by restricting the ratio range of d0m / (f × tan(FOV / 2)), not only can the relationship between the maximum field angle and the system focal length be controlled, so as to effectively improve the imaging quality of the optical lens while achieving the large image plane coverage ability; at the same time, by constraining the proportional relationship between the inner diameter of the image side of the lens barrel and the maximum field angle of the lens, the overall radial dimension of the optical lens can be significantly reduced, meeting the miniaturization integration requirements.

[0117] Preferably, the optical lens satisfies: 3.05 ≤ d0m / (f × tan(FOV / 2)) ≤ 3.97.

[0118] It should be noted that those skilled in the art should understand that, without departing from the technical solutions claimed in this application, the number of spacers constituting the optical lens can be changed to obtain the various results and advantages described in this specification, and this application does not specifically limit this. For example, as needed, the optical imaging lens may also include other numbers of spacers than those described in the above embodiments.

[0119] The following describes in more detail, with reference to the accompanying drawings, some specific, non-limiting embodiments of the above-described embodiments of this application. For ease of description, in the following embodiments, OBJ (not shown in the figures) represents the object plane of the optical lens, STO (not shown in the figures) represents the surface of the aperture stop, S1 represents the object-side plane of the first lens E1, S2 represents the image-side plane of the first lens E1, S3 represents the object-side plane of the second lens E2, S4 represents the image-side plane of the second lens E2, S5 represents the object-side plane of the third lens E3, S6 represents the image-side plane of the third lens E3, S7 represents the object-side plane of the fourth lens E4, S8 represents the image-side plane of the fourth lens E4, S9 (not shown in the figures) is the object-side plane of one of the first filter or the first protective glass, S10 (not shown in the figures) is the image-side plane of one of the first filter or the first protective glass, S11 (not shown in the figures) is the object-side plane of one of the second filter or the second protective glass, S12 (not shown in the figures) is the image-side plane of one of the second filter or the second protective glass, and S13 (not shown in the figures) is the imaging plane of the optical imaging system. Furthermore, let Aj denote the j-th order aspherical coefficient, j=4, 6, 8, 10, 12, 14, 16...30.

[0120] Example 1

[0121] like Figure 2 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacers housed within the lens barrel P0; the lens group includes a first lens E1, a second lens E2, a third lens E3 and a fourth lens E4 arranged sequentially along the optical axis from the object side to the image side; the plurality of spacers include a first spacer P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0122] In this embodiment, the plurality of spacers further includes a first auxiliary spacer P1b disposed between the first lens E1 and the second lens E2 and in contact with the image side of the first spacer P1, and a second auxiliary spacer P2b disposed between the second lens E2 and the third lens E3 and in contact with the image side of the second spacer P2.

[0123] In this embodiment, the first lens E1 has positive optical power, and the object-side surface S1 and the image-side surface S2 of the first lens E1 are concave and convex, respectively; the second lens E2 has positive optical power, and the object-side surface S3 and the image-side surface S4 of the second lens E2 are convex and concave, respectively; the third lens E3 has positive optical power, and the object-side surface S5 and the image-side surface S6 of the third lens E3 are both convex; the fourth lens E4 has positive optical power, and the object-side surface S7 and the image-side surface S8 of the fourth lens E4 are convex and concave, respectively.

[0124] In addition, Table 1 shows the basic optical parameters of the optical imaging lens of Embodiment 1, where the units of radius of curvature and thickness / distance are millimeters (mm).

[0125] Table 1: Basic optical parameters of the optical lens in Example 1

[0126]

[0127] In this embodiment, the object-side surface and image-side surface of any one of the first lens E1 to the fourth lens E4 are aspherical, and the surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0128] ;

[0129] Where x is the distance vector from the vertex of the aspherical surface at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., 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 i-th order correction coefficient of the aspherical surface. Tables 2-1 and 2-2 below give the higher-order coefficients A4, A6, A8, A10, A12, A14, A16...A22 that can be used for each aspherical mirror S1 to S8 in Example 1.

[0130] Table 2-1: Aspherical coefficient table of the optical lens in Example 1

[0131]

[0132] Table 2-2: Aspherical coefficients of the optical lens in Example 1

[0133]

[0134] Example 2

[0135] like Figure 3 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with positive optical power arranged sequentially along the optical axis from the object side to the image side; the plurality of spacer elements include a first spacer element P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0136] It is worth noting that, compared with Embodiment 1 above, the optical lens of Embodiment 2 has the same optical parameters, that is, the basic optical parameter table of the optical lens of Embodiment 2 is the same as Table 1, and the aspherical coefficient table is the same as Tables 2-1 and 2-2. However, the optical lens of Embodiment 2 has different structural parameters than the optical lens of Embodiment 1 above. That is, the difference between Embodiment 2 and Embodiment 1 above lies in the different dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens.

[0137] Specifically, the values ​​of various related structural parameters in this embodiment and the above embodiment are shown in Table 8 below. These structural parameters specifically include: the object-side inner diameter d1s of the first spacer element P1; the image-side inner diameter d1m of the first spacer element P1; the object-side outer diameter D1s of the first spacer element P1; the object-side inner diameter d2s of the second spacer element P2; the object-side outer diameter D2s of the second spacer element P2; the object-side inner diameter d0s of the lens barrel P0; the image-side inner diameter d0m of the lens barrel P0; the object-side outer diameter D0s of the lens barrel P0; and the image-side outer diameter D0m of the lens barrel P0. The maximum thickness CP1b of the first auxiliary spacer element P1b; the distance EP01 between the object side of the lens barrel P0 and the object side of the first spacer element P1 along the optical axis; the maximum thickness CP1 of the first spacer element P1; the distance EP12 between the image side of the first spacer element P1 and the object side of the second spacer element P2 along the optical axis; the maximum height L of the lens barrel P0; the distance EP02 between the object side of the lens barrel P0 and the object side of the second spacer element P2 along the optical axis; the sum of the maximum thicknesses of the first spacer element P1 and the first auxiliary spacer element P1b along the optical axis ∑CP1. It is understood that the units of the values ​​of each parameter shown in Table 8 are millimeters (mm), and the schematic diagrams of each parameter in the optical lens structure are as follows: Figure 1A as well as Figure 1B As shown.

[0138] Example 3

[0139] like Figure 4 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with positive optical power arranged sequentially along the optical axis from the object side to the image side; the plurality of spacer elements include a first spacer element P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0140] It is worth noting that, compared with Embodiment 1 above, the optical lens of Embodiment 3 has the same optical parameters. That is, the basic optical parameter table of the optical lens of Embodiment 3 is the same as Table 1, and the aspherical coefficient table is the same as Tables 2-1 and 2-2. However, the optical lens of Embodiment 3 has different structural parameters than the optical lens of Embodiment 1 above. That is, the difference between Embodiment 3 and Embodiment 1 is that the dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens are different. Specifically, the values ​​of each relevant structural parameter in Embodiment 3 are shown in Table 8 below. The specific descriptions of the multiple structural parameters are the same as those in Embodiment 2 above, and will not be repeated here.

[0141] The on-axis chromatic aberration curves of the optical lenses in Examples 1, 2, and 3 are as follows: Figure 5A As shown, this represents the degree of deviation of the focal point after light of different wavelengths passes through the optical lens; the astigmatism curves of the optical lenses in Embodiments 1, 2, and 3 are shown below. Figure 5B As shown, it represents the curvature of the meridional image plane and the curvature of the sagittal image plane; the distortion curves of the optical lenses in Embodiments 1, 2, and 3 are shown in the schematic diagram. Figure 5C As shown; schematic diagrams of the magnification chromatic aberration curves of the optical lenses in Embodiments 1, 2, and 3 are shown below. Figure 5D As shown. According to Figure 5A , Figure 5B , Figure 5C as well as Figure 5D It can be seen that the optical lenses in Embodiment 1, Embodiment 2 and Embodiment 3 can all achieve good imaging quality.

[0142] Example 4

[0143] like Figure 6 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes, arranged sequentially along the optical axis from the object side to the image side: a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with negative optical power; the plurality of spacer elements include a first spacer element P1 located on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 located on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 located on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0144] In this embodiment, the first lens E1 has positive optical power, and the object-side surface S1 and image-side surface S2 of the first lens E1 are concave and convex, respectively; the second lens E2 has positive optical power, and the object-side surface S3 and image-side surface S4 of the second lens E2 are convex and concave, respectively; the third lens E3 has positive optical power, and the object-side surface S5 and image-side surface S6 of the third lens E3 are both convex; the fourth lens E4 has negative optical power, and the object-side surface S7 and image-side surface S8 of the fourth lens E4 are convex and concave, respectively.

[0145] In addition, Table 3 shows the basic optical parameters of the optical imaging lens of Embodiment 4, wherein the units of radius of curvature, thickness / distance and effective radius are all millimeters (mm).

[0146] Table 3: Basic optical parameters of the optical lens in Example 4

[0147]

[0148] In this embodiment, the object-side surface and image-side surface of any one of the first lens E1 to the fourth lens E4 are aspherical, and the surface shape of each aspherical lens can be defined by the aspherical formula given in Embodiment 1 above. Tables 4-1 and 4-2 below give the higher-order coefficients A4, A6, A8, A10, A12, A14, A16...A30 that can be used for each aspherical mirror S1-S8 in Embodiment 4.

[0149] Table 4-1: Aspherical coefficient table of the optical lens in Example 4

[0150]

[0151] Table 4-2: Aspherical coefficient table of the optical lens in Example 4

[0152]

[0153] Example 5

[0154] like Figure 7As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes, arranged sequentially along the optical axis from the object side to the image side: a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with negative optical power; the plurality of spacer elements include a first spacer element P1 located on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 located on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 located on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0155] It is worth noting that, compared with Embodiment 4 above, the optical lens of Embodiment 5 has the same optical parameters. That is, the basic optical parameter table of the optical lens of Embodiment 5 is the same as Table 3, and the aspherical coefficient table is the same as Tables 4-1 and 4-2. However, the optical lens of Embodiment 5 has different structural parameters than the optical lens of Embodiment 4 above. That is, the difference between Embodiment 5 and Embodiment 4 above lies in the different dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens. Specifically, the values ​​of each relevant structural parameter in Embodiment 5 are shown in Table 8 below. The specific descriptions of the multiple structural parameters are the same as those in Embodiment 2 above, and will not be repeated here.

[0156] Example 6

[0157] like Figure 8 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes, arranged sequentially along the optical axis from the object side to the image side: a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with negative optical power; the plurality of spacer elements include a first spacer element P1 located on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 located on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 located on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0158] It is worth noting that, compared with Embodiment 4 above, the optical lens of Embodiment 6 has the same optical parameters. That is, the basic optical parameter table of the optical lens of Embodiment 6 is the same as Table 3, and the aspherical coefficient table is the same as Tables 4-1 and 4-2. However, the optical lens of Embodiment 6 has different structural parameters than the optical lens of Embodiment 4 above. That is, the difference between Embodiment 6 and Embodiment 4 above lies in the different dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens. Specifically, the values ​​of each relevant structural parameter in Embodiment 6 are shown in Table 8 below. The specific descriptions of multiple structural parameters are the same as those in Embodiment 2 above, and will not be repeated here.

[0159] The on-axis chromatic aberration curves of the optical lenses in Examples 4, 5, and 6 are as follows: Figure 9A As shown, this indicates the degree of deviation of the focal point after light of different wavelengths passes through the optical lens; the astigmatism curves of the optical lenses in Examples 4, 5, and 6 are shown below. Figure 9B As shown, it represents the curvature of the meridional image plane and the curvature of the sagittal image plane; the distortion curves of the optical lenses in Embodiments 4, 5, and 6 are shown in the schematic diagram. Figure 9C As shown; schematic diagrams of the magnification chromatic aberration curves of the optical lenses in Examples 4, 5, and 6 are shown below. Figure 9D As shown. According to Figure 9A , Figure 9B , Figure 9C as well as Figure 9D It can be seen that the optical lenses in Embodiments 4, 5 and 6 can all achieve good imaging quality.

[0160] Example 7

[0161] like Figure 10 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with positive optical power arranged sequentially along the optical axis from the object side to the image side; the plurality of spacer elements include a first spacer element P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0162] In this embodiment, the first lens E1 has positive optical power, and the object-side surface S1 and image-side surface S2 of the first lens E1 are concave and convex, respectively; the second lens E2 has positive optical power, and the object-side surface S3 and image-side surface S4 of the second lens E2 are convex and concave, respectively; the third lens E3 has positive optical power, and the object-side surface S5 and image-side surface S6 of the third lens E3 are concave and convex, respectively; the fourth lens E4 has positive optical power, and the object-side surface S7 and image-side surface S8 of the fourth lens E4 are convex and concave, respectively.

[0163] In addition, Table 5 shows the basic optical parameters of the optical imaging lens of Embodiment 7, wherein the units of radius of curvature, thickness / distance and effective radius are all millimeters (mm).

[0164] Table 5: Basic optical parameters of the optical lens in Example 7

[0165]

[0166] In this embodiment, the object-side and image-side surfaces of the fourth lens E4 are spherical, while the object-side and image-side surfaces of any one of the first lens E1 to the third lens E3 are aspherical. The surface shape of each aspherical lens can be defined by the aspherical formula given in Embodiment 1 above. Tables 6-1 and 6-2 below give the higher-order coefficients A4, A6, A8, A10, A12, A14, A16...A26 that can be used for each aspherical mirror S1 to S6 in Embodiment 7.

[0167] Table 6-1: Aspherical coefficient table of the optical lens in Example 7

[0168]

[0169] Table 6-2: Aspherical coefficient table of the optical lens in Example 7

[0170]

[0171] Example 8

[0172] like Figure 11As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with positive optical power arranged sequentially along the optical axis from the object side to the image side; the plurality of spacer elements include a first spacer element P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0173] It is worth noting that, compared with Embodiment Seven above, the optical lens of Embodiment Eight has the same optical parameters, that is, the basic optical parameter table of the optical lens of Embodiment Eight is the same as Table 5, and the aspherical coefficient table is the same as Tables 6-1 and 6-2. However, the optical lens of Embodiment Eight has different structural parameters than the optical lens of Embodiment Seven above. That is, the difference between Embodiment Eight and Embodiment Seven above lies in the different dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens. Specifically, the values ​​of each relevant structural parameter in Embodiment Eight are shown in Table 8 below. The specific descriptions of the multiple structural parameters are the same as those in Embodiment Two above, and will not be repeated here.

[0174] Example 9

[0175] like Figure 12 As shown, in this embodiment, the optical lens includes a lens barrel P0 and a lens group and a plurality of spacer elements housed within the lens barrel P0; the lens group includes a first lens E1 with positive optical power, a second lens E2 with positive optical power, a third lens E3 with positive optical power, and a fourth lens E4 with positive optical power arranged sequentially along the optical axis from the object side to the image side; the plurality of spacer elements include a first spacer element P1 placed on the image side of the first lens E1 and in contact with the image side S2 of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and in contact with the image side S4 of the second lens E2, and a third spacer element P3 placed on the image side of the third lens E3 and in contact with the image side S6 of the third lens E3.

[0176] In this embodiment, the plurality of spacers further includes a first auxiliary spacer element P1b disposed between the first lens E1 and the second lens E2 and in contact with the image side of the first spacer element P1.

[0177] It is worth noting that, compared with Embodiment 7 above, the optical lens of Embodiment 9 has the same optical parameters. That is, the basic optical parameter table of the optical lens of Embodiment 9 is the same as Table 5, and the aspherical coefficient table is the same as Tables 6-1 and 6-2. However, the optical lens of Embodiment 9 has different structural parameters than the optical lens of Embodiment 7 above. That is, the difference between Embodiment 9 and Embodiment 7 is that the dimensional values ​​of some structural parameters of the lens barrel and multiple spacer elements in the optical lens are different. Specifically, the values ​​of each relevant structural parameter in Embodiment 9 are shown in Table 8 below. The specific descriptions of the multiple structural parameters are the same as those in Embodiment 2 above, and will not be repeated here.

[0178] The on-axis chromatic aberration curves of the optical lenses in Examples 7, 8, and 9 are as follows: Figure 13A As shown, this indicates the degree of deviation of the focal point after light of different wavelengths passes through the optical lens; the astigmatism curves of the optical lenses in Embodiments 7, 8, and 9 are shown below. Figure 13B As shown, it represents the curvature of the meridional image plane and the curvature of the sagittal image plane; the distortion curves of the optical lenses in Embodiments 7, 8, and 9 are shown in the schematic diagram. Figure 13C As shown; schematic diagrams of the magnification chromatic aberration curves of the optical lenses in Examples 7, 8, and 9 are shown below. Figure 13D As shown. According to Figure 13A , Figure 13B , Figure 13C as well as Figure 13D It can be seen that the optical lenses in Embodiments 7, 8 and 9 can all achieve good imaging quality.

[0179] In summary, in Embodiments 1 to 9, the maximum field of view (FOV) of the optical lens, the entrance pupil diameter (EPD) of the optical lens, the effective focal length (f) of the optical lens, the effective focal lengths (f1 to f4) of the first lens (E1) to the fourth lens (E4) in the optical lens, the combined focal length (f12) of the first lens (E1) and the second lens (E2), the maximum effective radius (DT21) of the object-side surface (S3) of the second lens (E2), the axial displacement (SAG11) between the intersection of the object-side surface (S1) of the first lens (E1) and the optical axis and the vertex of the effective radius of the object-side surface (S1) of the first lens (E1), the axial displacement (SAG12) between the intersection of the image-side surface (S2) of the first lens (E1) and the optical axis and the vertex of the effective radius of the image-side surface (S2) of the first lens (E1), the radii of curvature (R1 to R4) of the first lens (E1) to the fourth lens (E4), the center thicknesses (CT1 and CT2) of the first lens (E1) and the fourth lens (E4), and the refractive index (N1) of the first lens (E1) are shown in Table 7 below.

[0180] Table 7: System Optical Parameters of Optical Lenses

[0181]

[0182] Furthermore, the structural parameters of the optical lenses in Examples 1 to 9 are shown in Table 8.

[0183] Table 8: Structural Parameters of Optical Lenses

[0184]

[0185] In summary, the optical lenses in Examples 1 to 9 satisfy the relationships shown in Table 9, as detailed in Table 9.

[0186] Table 9: Relationships Satisfied by Optical Lenses

[0187]

[0188] It is worth mentioning that, according to one aspect of this application, one embodiment of this application further provides a lidar, which may include the aforementioned optical lens and photosensitive element, the photosensitive element being disposed on the image-side of the optical lens for imaging. It is understood that the photosensitive element mentioned in this application may be, but is not limited to, a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) device, and this application will not elaborate further on this.

[0189] Furthermore, according to another aspect of this application, one embodiment of this application further provides an electronic device that may include a lidar and a processor configured as described above. The lidar is communicatively connected to the processor for acquiring image data and inputting the image data into the processor for processing. It is understood that the electronic device mentioned in this application may be implemented, but is not limited to, a device such as a car equipped with the lidar, and this application will not elaborate further on this.

[0190] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0191] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An optical lens characterized in that: A lens barrel and a plurality of spacer elements accommodated in the lens barrel; the lens barrel is composed of, in order from an object side to an image side along an optical axis, a first lens having a positive refractive power, a second lens having a positive refractive power, a third lens having a positive refractive power, and a fourth lens having a refractive power; the object side of the first lens is concave and the image side is convex, the object side of the second lens is convex and the image side is concave, the image side of the third lens is convex, and the object side of the fourth lens is convex and the image side is concave; the plurality of spacer elements include a first spacer element disposed on and in contact with the image side of the first lens and a second spacer element disposed on and in contact with the image side of the second lens; the optical lens satisfies: 1.35 < d0s / EPD < 1.60; -3.10 < f1 / (R1+R2) < -1.30; and 1.15 < (d0s-d1s) / EP01 < 2.00; wherein d0s is an inner diameter of the object side of the lens barrel; EPD is an entrance pupil diameter of the optical lens; f1 is an effective focal length of the first lens; R1 is a radius of curvature of the object side of the first lens; R2 is a radius of curvature of the image side of the first lens; d1s is an inner diameter of the object side of the first spacer element; and EP01 is a distance between the object side of the lens barrel and the object side of the first spacer element along the optical axis.

2. The optical lens of claim 1, wherein, The optical lens satisfies: 1.45 < EP01 / (SAG11+SAG12) < 1.80; wherein EP01 is a distance between the object side of the lens barrel and the object side of the first spacer element along the optical axis, SAG11 is an on-axis displacement between the intersection of the object side of the first lens and the optical axis and the effective radius vertex of the object side of the first lens, and SAG12 is an on-axis displacement between the intersection of the image side of the first lens and the optical axis and the effective radius vertex of the image side of the first lens.

3. The optical lens of claim 1, wherein, The optical lens satisfies: 0.20 < (d0m-d0s) / f < 1.00; wherein f is an effective focal length of the optical lens, d0s is an inner diameter of the object side of the lens barrel, and d0m is an inner diameter of the image side of the lens barrel.

4. The optical lens of claim 1, wherein, The optical lens satisfies: 5.45 < d0s / CT1 < 7.00; wherein d0s is an inner diameter of the object side of the lens barrel, and CT1 is a center thickness of the first lens.

5. The optical lens of claim 1, wherein, The optical lens satisfies: 2.75 < f1 / (EP01×N1×10) < 4.65; wherein f1 is an effective focal length of the first lens, EP01 is a distance between the object side of the lens barrel and the object side of the first spacer element along the optical axis, and N1 is a refractive index of the first lens.

6. The optical lens of claim 1, wherein, The optical lens satisfies: 0.00 ≤ CP1 / (D1s-d1s) < 0.30; wherein CP1 is a maximum thickness of the first spacer element along the optical axis, D1s is an outer diameter of the object side of the first spacer element, and d1s is an inner diameter of the object side of the first spacer element.

7. The optical lens of claim 1, wherein, The plurality of spacer elements further comprises a first auxiliary spacer element disposed between the first lens and the second lens and in contact with the image-side surface of the first spacer element, and the optical lens satisfies: 0.00 < ∑CP1 / (CT1+CT2) < 0.45; wherein ∑CP1 is the sum of the maximum thicknesses of the first spacer element and the first auxiliary spacer element along the optical axis direction, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

8. The optical lens of claim 1, wherein, The optical lens satisfies: 1.90 < d1m / DT21 < 2.25; wherein d1m is the image-side inner diameter of the first spacer element, and DT21 is the maximum effective radius of the object-side surface of the second lens.

9. The optical lens of claim 1, wherein, The optical lens satisfies: 0.50 < EP12 / R3 < 1.00; wherein EP12 is the distance between the image-side surface of the first spacer element and the object-side surface of the second spacer element along the optical axis direction, and R3 is the curvature radius of the object-side surface of the second lens.

10. The optical lens of claim 1, wherein, The optical lens satisfies: 2.85 ≤ L / EP02 < 4.10; wherein L is the maximum height of the lens barrel, and EP02 is the distance between the object-side surface of the lens barrel and the object-side surface of the second spacer element along the optical axis direction.

11. The optical lens of claim 1, wherein, The optical lens satisfies: 3.45 < f12 / (d1s+d2s) < 5.20; wherein f12 is the combined focal length of the first lens and the second lens, d1s is the object-side inner diameter of the first spacer element, and d2s is the object-side inner diameter of the second spacer element.

12. The optical lens of claim 1, wherein, The optical lens satisfies: 0.40 < (D2s-d2s) / d2s < 0.95; wherein D2s is the object-side outer diameter of the second spacer element, and d2s is the object-side inner diameter of the second spacer element.

13. The optical lens of any of claims 1-12, wherein, The optical lens satisfies: 0.45 < L / (D0m+D0s) < 0.60; wherein L is the maximum height of the lens barrel, D0m is the image-side outer diameter of the lens barrel, and D0s is the object-side outer diameter of the lens barrel.

14. The optical lens of any of claims 1-12, wherein, The optical lens satisfies: 3.05 ≤ d0m / (f×tan(FOV / 2)) < 4.00; wherein d0m is the image-side inner diameter of the lens barrel, f is the effective focal length of the optical lens, and FOV is the maximum field of view angle of the optical lens.

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