Optical lenses and electronic equipment

Abstract

The present application discloses an optical lens and an electronic device. The optical lens includes, in order from the first side to the second side along the optical axis: a first lens with negative optical focal length; a second lens with negative optical focal length, whose first side is convex and whose second side is concave; a third lens with positive optical focal length, whose first side is convex; and a fourth lens with optical focal length, whose first side is convex and whose second side is concave. The number of lenses with optical focal length in the optical lens is four. The effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula F2 / F≤-2.5; the radius of curvature R3 of the first side of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula 0<R3 / F≤8.

Description

Technical Field

[0001] The present application relates to the field of optical elements, and more specifically, to an optical lens and an electronic device. Background Art

[0002] In recent years, optical lens technology has been continuously developing and improving. Optical lenses are increasingly widely used in many fields including smart phones, security monitoring, car assisted driving, intelligent detection and virtual reality. Among them, in the application of the automotive field, LiDAR lenses are key components for automatic driving assistance systems to obtain external information. With the rapid development of automatic driving assistance systems, people's demand for LiDAR lenses is also increasing, and LiDAR lenses are continuously developing in the direction of high resolution and miniaturization.

[0003] In order to meet the requirements of safe driving and special installation locations, people have more special requirements for lidar lenses in autonomous driving assistance systems compared to ordinary optical lenses. For example, in order to achieve long-distance measurement, the light transmittance of the receiving lens module needs to be increased, which requires a larger light aperture and a small FNO.

[0004] However, there are still many deficiencies in existing optical lenses, which need to be improved and enhanced. For example, existing optical lenses often have low light transmission capabilities and cannot adapt to dark environments at night or on rainy days; existing optical lenses usually cannot simultaneously meet the requirements of small apertures under small FNO conditions; in addition, existing optical lenses usually also find it difficult to simultaneously meet the requirements of high resolution under small FNO conditions. Therefore, optical lenses with better characteristics in aspects such as high resolution, miniaturization, and small FNO are the current research and development direction of those skilled in the art. Summary of the invention

[0005] The present application provides an optical lens, which may include, in order from the first side to the second side along the optical axis: a first lens with negative optical power; a second lens with negative optical power, whose first side surface is convex and whose second side surface is concave; a third lens with positive optical power, whose first side surface is convex; and a fourth lens with optical power, whose first side surface is convex and whose second side surface is concave; and the number of lenses with optical power in the optical lens is four. The effective focal length F2 of the second lens and the total effective focal length F of the optical lens may satisfy: F2 / F≤-2.5; the radius of curvature R3 of the first side surface of the second lens and the total effective focal length F of the optical lens may satisfy: 0<R3 / F≤8.

[0006] In one embodiment, the first side surface of the first lens is a concave surface, and the second side surface is a convex surface or a plane.

[0007] In one embodiment, the first side surface of the first lens is convex, and the second side surface is concave.

[0008] In one embodiment, the second side surface of the third lens is a concave surface, a flat surface or a convex surface.

[0009] In one embodiment, the fourth lens has positive or negative optical power.

[0010] In one embodiment, the distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, the maximum field of view FOV of the optical lens, and the image height H corresponding to the maximum field of view of the optical lens may satisfy: 0.2≤TTL / H / FOV≤0.35.

[0011] In one embodiment, the total effective focal length F of the optical lens, the arc value θ of the maximum field angle of the optical lens, and the maximum effective light aperture D of the first side surface of the first lens corresponding to the maximum field angle of the optical lens may satisfy: 0.2≤(F×θ) / D≤0.4.

[0012] In one embodiment, the total effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens may satisfy: F / ENPD≤1.2.

[0013] In one embodiment, the total effective focal length F of the optical lens and the image height H corresponding to the maximum field angle of the optical lens may satisfy: 1.5≤F / H≤2.2.

[0014] In one embodiment, a distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis and a total effective focal length F of the optical lens may satisfy: 3≤TTL / F≤6.

[0015] In one embodiment, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens may satisfy: -13≤F1 / F≤-2.

[0016] In one embodiment, the effective focal length F3 of the third lens and the total effective focal length F of the optical lens may satisfy: 0<F3 / F≤3.

[0017] In one embodiment, the effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens may satisfy: 1.5≤|F4 / F|≤13.

[0018] In one embodiment, the radius of curvature R7 of the first side surface of the fourth lens and the total effective focal length F of the optical lens may satisfy: 0<R7 / F≤2.

[0019] In one embodiment, the air gap d2 between the first lens and the second lens on the optical axis, the air gap d4 between the second lens and the third lens on the optical axis, and the distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis may satisfy: 0.2≤(d2+d4) / TTL≤0.55.

[0020] In one embodiment, the entrance pupil diameter ENPD of the optical lens, the maximum field of view FOV of the optical lens, and the image height H corresponding to the maximum field of view of the optical lens may satisfy: 0.02≤ENPD / H / FOV≤0.15.

[0021] In one embodiment, a curvature radius R7 of the first side surface of the fourth lens, a curvature radius R8 of the second side surface of the fourth lens, and a center thickness d7 of the fourth lens on the optical axis may satisfy: 0.3≤R7 / (R8+d7)≤1.2.

[0022] In one embodiment, the optical lens may satisfy at least one of the following conditions: 4.5≤D / H / θ≤7; 0.1≤D / H / F≤0.3; 0.05≤BFL / TTL≤0.25; 1.5≤|F2 / F3|≤12; 0.8≤(H / 2) / (F×tan(θ / 2))≤1.2; |R6 / R7|≥2; 1≤FOV / F≤3; |R5 / R6|<1; 0<|R1 / R2|<3; wherein D is the maximum effective aperture of the first side of the first lens corresponding to the maximum field of view of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, and θ is the maximum effective aperture of the first side of the first lens corresponding to the maximum field of view of the optical lens. F is the total effective focal length of the optical lens, TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, BFL is the distance from the center of the second side surface of the fourth lens to the imaging surface on the optical axis, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, R6 is the radius of curvature of the second side surface of the third lens, R7 is the radius of curvature of the first side surface of the fourth lens, FOV is the maximum field of view of the optical lens, R5 is the radius of curvature of the first side surface of the third lens, R1 is the radius of curvature of the first side surface of the first lens, and R2 is the radius of curvature of the second side surface of the first lens.

[0023] In one embodiment, the optical lens may satisfy at least one of the following conditions: 0.25≤TTL / H / FOV≤0.3; 5.2≤D / H / θ≤6.8; 0.16≤D / H / F≤0.22; 0.26≤(F×θ) / D≤0.37; 0.08≤BFL / TTL≤0.22; 2.3≤|F2 / F3|≤11.2; 0.9≤F / ENPD≤1.1; 1.7≤F / H≤2.0; 4.5≤TTL / F≤5.1; -11.8≤F1 / F≤-3.3; -18.8≤F2 / F≤-4.1; 1.1≤F3 / F≤2.0; 1.9≤|F4 / F|≤12.4; 0.9≤(H / 2) / (F×tan(θ / 2))≤1.05; 3.4≤|R6 / R7|≤18.0; 0.7≤R7 / F≤1.4; 0.25≤(d2+d4) / T TL≤0.53; 1.3≤R3 / F≤7.5; 1.7≤FOV / F≤2.0; 0.05≤ENPD / H / FOV≤0.07; 0.4≤R7 / (R8+d7)≤0.9; 0<|R5 / R6|≤0.5; 0<|R1 / R2|≤2. 3; wherein, TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, FOV is the maximum field of view of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, D is the maximum effective aperture of the first side surface of the first lens corresponding to the maximum field of view of the optical lens, θ is the radian value of the maximum field of view of the optical lens, F is the total effective focal length of the optical lens, BFL is the distance from the center of the second side surface of the fourth lens to the imaging surface on the optical axis, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, F4 is the effective focal length of the fourth lens, R6 is the curvature radius of the second side surface of the third lens, R7 is the curvature radius of the first side surface of the fourth lens, d2 is the air distance between the first lens and the second lens on the optical axis, d4 is the air distance between the second lens and the third lens on the optical axis, R3 is the curvature radius of the first side surface of the second lens, ENPD is the entrance pupil diameter of the optical lens, R8 is the curvature radius of the second side surface of the fourth lens, d7 is the center thickness of the fourth lens on the optical axis, R5 is the curvature radius of the first side surface of the third lens, R1 is the curvature radius of the first side surface of the first lens, and R2 is the curvature radius of the second side surface of the first lens.

[0024] On the other hand, the present application provides an electronic device, which includes the optical lens provided according to the present application and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

[0025] According to the embodiment of the present application, the optical lens includes four lenses with optical power, which are the first to fourth lenses arranged in sequence from the first side to the second side along the optical axis, wherein the first lens has negative optical power; the second lens has negative optical power, and its first side surface is convex, and the second side surface is concave; the third lens has positive optical power, and its first side surface is convex; the fourth lens has positive optical power or negative optical power, and its first side surface is convex, and the second side surface is concave; the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula F2 / F≤-2.5; the curvature radius R3 of the first side surface of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula 0<R3 / F≤8. Through this setting of the lens, the focal length of the second lens can be reasonably distributed, which is conducive to better receiving the light entering through the first lens. The second lens is set as a telephoto lens, so that the peripheral light entering through the first lens can transition smoothly, which is conducive to reducing sensitivity and improving imaging quality; with the setting that the object side of the second lens is convex, the light diverging from the front can be quickly contracted and smoothly enter the rear optical system, which is conducive to reducing the system aperture and making the overall light trend of the system smooth.

[0026] The optical lens according to the exemplary embodiment of the present application adopts a four-piece lens architecture. By reasonably setting parameters such as the lens optical power, surface shape, radius of curvature, center thickness, and air spacing between lenses on the optical axis, the optical lens can have one or more beneficial effects such as high resolution, miniaturization, and small FNO, so that the optical lens can better meet the high requirements of automotive applications such as lidar lenses. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Other features, purposes and advantages of the present application will become more apparent through the following detailed description of the embodiments in conjunction with the accompanying drawings. In the accompanying drawings:

[0028] Figure 1 A schematic diagram showing the structure of an optical lens according to Embodiment 1 of the present application;

[0029] Figure 2 A schematic diagram showing the structure of an optical lens according to Embodiment 2 of the present application;

[0030] Figure 3 A schematic diagram showing the structure of an optical lens according to Embodiment 3 of the present application;

[0031] Figure 4 A schematic diagram showing the structure of an optical lens according to Embodiment 4 of the present application;

[0032] Figure 5 A schematic diagram showing the structure of an optical lens according to Embodiment 5 of the present application;

[0033] Figure 6A schematic diagram showing the structure of an optical lens according to Embodiment 6 of the present application;

[0034] Figure 7 A schematic diagram showing the structure of an optical lens according to Embodiment 7 of the present application;

[0035] Figure 8 A schematic diagram showing the structure of an optical lens according to Example 8 of the present application;

[0036] Fig. 9 A schematic diagram showing the structure of an optical lens according to Example 9 of the present application;

[0037] Fig.10 A schematic diagram showing the structure of an optical lens according to Embodiment 10 of the present application;

[0038] Fig.11 A schematic diagram showing the structure of an optical lens according to Example 11 of the present application;

[0039] Fig.12 A schematic diagram showing the structure of an optical lens according to Embodiment 12 of the present application;

[0040] Fig.13 A schematic diagram showing the structure of an optical lens according to Embodiment 13 of the present application;

[0041] Fig.14 A schematic diagram showing the structure of an optical lens according to Embodiment 14 of the present application;

[0042] Fig.15 , Fig.16 and Fig.17 1 and 2 respectively show an MTF diagram, an optical point diagram, and a diffraction circle energy diagram of the optical lens according to Example 1 of the present application;

[0043] Fig.18 , Fig.19 and Fig. 20 10 are respectively an MTF diagram, an optical point diagram and a diffraction circle energy diagram of the optical lens according to Example 3 of the present application;

[0044] Fig.21 , Fig. 22 and Fig.23 10 are respectively an MTF diagram, an optical point diagram and a diffraction circle energy diagram of the optical lens according to Example 5 of the present application;

[0045] Fig.24 , Fig.25 and Fig.26 1 and 2 respectively show the MTF diagram, optical point diagram and diffraction circle energy diagram of the optical lens according to Example 6 of the present application. DETAILED DESCRIPTION

[0046] In order to facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and do not limit the scope of the present application in any way. Throughout the specification, the same figure numbers refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0047] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

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

[0049] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object side of the lens, and the surface of each lens closest to the imaging side is called the image side of the lens.

[0050] It should be understood that the optical lens provided in the present application can be used for both video recording and projection. When the optical lens provided in the present application is used for a video recording lens, the "first side" referred to in this article may refer to the object side, and the "second side" may refer to the image side; when the optical lens provided in the present application is used for a projection lens or a radar transmitting lens, the "first side" referred to in this article may refer to the imaging side, and the "second side" may refer to the image source side.

[0051] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0052] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0053] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0054] The features, principles and other aspects of the present application are described in detail below.

[0055] In an exemplary embodiment, the optical lens includes, for example, four lenses having optical power, namely, a first lens, a second lens, a third lens, and a fourth lens. The four lenses may be arranged in sequence from the first side to the second side along the optical axis.

[0056] In an exemplary embodiment, the first side may be, for example, the object side, and the second side may be, for example, the image side. Accordingly, the first side surface of each lens in the first lens, the second lens, the third lens, and the fourth lens may be the object side surface of each lens, and the second side surface of each lens may be the image side surface of each lens.

[0057] In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the imaging surface. Optionally, the photosensitive element disposed on the imaging surface may be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS).

[0058] In an exemplary embodiment, the optical lens may further include a filter disposed between the fourth lens and the imaging surface. The filter may filter light having a specific wavelength.

[0059] In an exemplary embodiment, the first lens may have a negative optical power. The first lens may have a concave-convex surface. The first lens has a negative optical power, which may have a divergent effect on the light passing through it, which is beneficial to a small front aperture; the object side of the first lens is a concave surface, which may allow the collected light to enter the first lens in a divergent form as much as possible, while effectively reducing the angle between the edge field of view light and the first side when incident, thereby improving the relative illumination of the edge of the lens as a whole; the image side of the first lens is a convex surface, which may appropriately converge and gather the light, and allow the light to enter the rear optical system as smoothly as possible, which is beneficial to the low sensitivity of the system. The object side of the first lens is a concave surface, which may also be beneficial to avoid contact and friction between the lens and other objects, and is beneficial to the protection of the lens and the film layer. In an exemplary embodiment, the first lens may use a high refractive index material, which may be beneficial to the reduction of the front aperture and the improvement of the imaging quality.

[0060] In an exemplary embodiment, the first lens may have a negative optical power. The first lens may have a concave plane type. The first lens has a negative optical power and has a divergent effect on the light. The object side surface of the first lens is a concave surface, which can make the incident light enter the rear optical system in a divergent form, which is conducive to reducing the front port diameter. The image side surface of the first lens is a plane, which has no deflection effect on the front divergent light, and can make the light diverged through the object side quickly enter the rear optical system, which is conducive to improving the rear optical effective aperture position, expanding the aperture of the aperture, and achieving a small FNO.

[0061] In an exemplary embodiment, the first lens may have a negative optical power. The first lens may have a convex-concave surface. The first lens has a negative optical power and has the function of diverging light, and can disperse the central light and the edge light of each field of view. Under the same field of view angle, the light emitted from the image side of the first lens can enable the rear optical system to have a larger light receiving surface, so that the physical aperture of the aperture is expanded, and a larger amount of light is achieved, which is beneficial to increase the illumination of the picture; the object side of the first lens is designed to be a convex surface, which cooperates with the concave surface of the image side, so that the light emitted from the first lens is smoothly incident to the rear, which is beneficial to reduce sensitivity and improve resolution; the object side of the first lens is designed to be a convex surface, which is also beneficial to the sliding of water droplets in practical applications, reducing the impact on imaging.

[0062] In an exemplary embodiment, the second lens may have a negative optical power. The second lens may have a convex-concave surface. The second lens has a negative optical power and has the function of diverging light. Under the same field of view angle, the light emitted from the image side of the first lens is further diverged, and the central light and the edge light of each field of view can be dispersed. In combination with the first lens, the rear optical system can have a larger light receiving surface to receive the light emitted from the image side of the second lens, so that the physical aperture of the aperture is expanded, and a larger amount of light is achieved, which is conducive to increasing the illumination of the picture. The object side of the second lens is a convex surface, which is conducive to the rapid collection of the divergent light from the first lens, so that the light emitted from the first lens is smoothly incident on the image side of the second lens, which is conducive to reducing the sensitivity of the light from the first lens to the second lens; setting the image side of the second lens to a concave surface can control the direction of the light at the edge of the lens, and the peripheral light emitted from the image side of the second lens can reach a higher imaging position, which is conducive to achieving a small FNO. At the same time, the light can be smoothly transitioned, which is conducive to improving the imaging quality.

[0063] In an exemplary embodiment, the second lens may be made of a high refractive index material, and the refractive index Nd2 of the second lens may satisfy Nd2≥1.8, for example, which is beneficial to reducing the front port diameter and improving the imaging quality.

[0064] In an exemplary embodiment, the third lens may have positive optical power. The third lens may have a convex-concave surface. The third lens has positive optical power and has the function of converging light. When combined with the negative optical power of the second lens, it is beneficial for the light to smoothly enter the rear optical system. The object side of the third lens is convex, and the radius of curvature is relatively small, which can make the light converge quickly, which is beneficial for the small aperture of the rear lens, and at the same time can reduce the total length of the system as much as possible to achieve miniaturization. The image side of the third lens is designed to be concave, which can appropriately diverge the light, which is beneficial for adjusting the optical path difference between light rays in different fields of view, paving the way for subsequent light rays to converge better to the image plane, and achieving high resolution.

[0065] In an exemplary embodiment, the third lens may have positive focal power. The third lens may have a convex plane type. The third lens has positive focal power and has the function of converging light. When combined with the negative focal power of the second lens, it is beneficial for light to smoothly enter the rear optical system. The object side of the third lens is designed to be convex, and the radius of curvature is relatively small, which has the function of converging light, and can make the divergent light passing through the second lens quickly converge to the rear optical system, reduce the total length of the system as much as possible, and achieve miniaturization. The image side of the third lens is a plane, which can receive the front convergent light and allow the light to smoothly enter the rear optical system.

[0066] In an exemplary embodiment, the third lens may have positive optical power. The third lens may have a convex-convex surface. The third lens has positive optical power, and the lens shape is biconvex, which is conducive to the rapid convergence of light. When combined with the negative optical power of the second lens, it is conducive to the smooth entry of light into the rear optical system. The object side of the third lens is a convex surface, so that the light emitted by the second lens converges quickly, reducing the rear port diameter and the total length of the system. The use of high refractive index materials can make the light show a convergence trend, appropriately weaken the divergence, and make the subsequent trend of peripheral light smooth, which is conducive to the rapid collection of light. The image side of the third lens is a convex surface, and the radius of curvature is relatively large, which can make the light smoothly transition to the fourth lens, which is conducive to reducing sensitivity and improving resolution.

[0067] In an exemplary embodiment, the fourth lens may have positive optical power. The fourth lens may have a convex-concave surface. The fourth lens has positive optical power, the object side surface is convex, and the image side surface is concave, which is conducive to proper convergence of light. The shape of the fourth lens is a meniscus (approximately concentric circles), which can make the front large-diameter light quickly and smoothly enter the rear optical system, reduce the back focus to a certain extent, and then reduce the total length of the system, reduce the system sensitivity, and improve the resolution. The fourth lens can be an aspherical lens, and its object side surface and / or image side surface can be aspherical, and the curvature of each position of the aspherical surface is different, which can effectively correct aberrations and field curvatures and improve the resolution of the optical system.

[0068] In an exemplary embodiment, the fourth lens may have a negative optical power. The fourth lens may have a convex-concave surface. The fourth lens has a negative optical power, which is conducive to the proper divergence of light and can further increase the focal length of the entire lens; the shape of the fourth lens is a meniscus (approximately concentric circles), which is conducive to better control of the smooth transition of light to the image plane, balance the resolution of each field of view, reduce the sensitivity of the system, and improve the resolution of the system. The fourth lens can be an aspherical lens, and its object side and / or image side can be an aspherical surface. The curvature of each position of the aspherical surface is different, which can effectively correct aberrations and field curvatures and improve the resolution of the optical system.

[0069] In an exemplary embodiment, the optical lens may further include an aperture. The aperture may be located, for example, between the second lens and the third lens. Reasonable setting of the position of the aperture, such as between the second lens and the third lens, may facilitate the effective and smooth transition of light entering the optical system to the rear end of the system, reduce the lens aperture at the rear end of the optical system, and reduce the assembly sensitivity of the system. However, it should be noted that the position of the aperture disclosed herein is only an example and not a limitation; in alternative embodiments, the aperture may also be set at other positions according to actual needs.

[0070] In an exemplary embodiment, the first to fourth lenses may have one or more aspherical mirror surfaces. Aspherical mirror surfaces have better curvature radius characteristics, can effectively correct aberrations and field curvatures, and improve the resolution of the optical system; can improve distortion aberrations and astigmatism aberrations, eliminate aberrations that occur during imaging as much as possible, and improve the imaging quality of the lens. In an exemplary embodiment, the object side surface and / or image side surface of the third lens and / or the fourth lens may be, for example, an aspherical surface.

[0071] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.2≤TTL / H / FOV≤0.35, wherein TTL is the distance on the optical axis from the center of the first side of the first lens to the imaging surface of the optical lens, FOV is the maximum field of view of the optical lens, and H is the image height corresponding to the maximum field of view of the optical lens. By controlling the optical lens to satisfy the conditional formula 0.2≤TTL / H / FOV≤0.35, it can be beneficial to miniaturize the lens. More specifically, TTL, H and FOV can further satisfy: 0.25≤TTL / H / FOV≤0.3. By controlling this conditional formula, the miniaturization of the lens can be further achieved.

[0072] In an exemplary embodiment, the optical lens according to the present application may satisfy: 4.5≤D / H / θ≤7, wherein D is the maximum effective aperture of the first side of the first lens corresponding to the maximum field of view of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, and θ is the radian value of the maximum field of view of the optical lens. By controlling the optical lens to satisfy the conditional formula 4.5≤D / H / θ≤7, it can be beneficial to have a small front port diameter of the lens, which is beneficial to miniaturization. More specifically, D, H and θ can further satisfy: 5.2≤D / H / θ≤6.8. By controlling this conditional formula, it can be more beneficial to achieve a small front port diameter of the lens, which is more beneficial to achieve miniaturization of the lens.

[0073] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.1≤D / H / F≤0.3, wherein D is the maximum effective aperture of the first side of the first lens corresponding to the maximum field angle of the optical lens, H is the image height corresponding to the maximum field angle of the optical lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula 0.1≤D / H / F≤0.3, the lens can be provided with the characteristics of a large target surface and a small aperture under the condition of a fixed focal length. More specifically, D, H and F can further satisfy: 0.16≤D / H / F≤0.22. By controlling this conditional formula, the lens can be better provided with the characteristics of a large target surface and a small aperture under the condition of a fixed focal length.

[0074] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.2≤(F×θ) / D≤0.4, wherein F is the total effective focal length of the optical lens, θ is the radian value of the maximum field of view of the optical lens, and D is the maximum effective aperture of the first side of the first lens corresponding to the maximum field of view of the optical lens. By controlling the optical lens to satisfy the conditional formula 0.2≤(F×θ) / D≤0.4, the front port diameter of the lens can be made smaller, the imaging system volume of the lens can be reduced, and long-distance detection can be achieved. More specifically, F, θ and D can further satisfy: 0.26≤(F×θ) / D≤0.37. By controlling this conditional formula, it can be more conducive to achieving a smaller front port diameter of the lens, further reducing the imaging system volume of the lens, and more conducive to achieving long-distance detection.

[0075] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.05≤BFL / TTL≤0.25, wherein BFL is the distance from the center of the second side of the fourth lens to the imaging surface of the optical lens on the optical axis, and TTL is the distance from the center of the first side of the first lens to the imaging surface on the optical axis. By controlling the optical lens to satisfy the conditional formula 0.05≤BFL / TTL≤0.25, it is possible to meet the special requirements of the optical lens for a short back focus, while ensuring space for component installation and focusing, and reducing the total length of the system, which is conducive to miniaturization. More specifically, BFL and TTL may further satisfy: 0.08≤BFL / TTL≤0.22. By controlling this conditional formula, the optical lens can better meet the special requirements of a short back focus, while ensuring space for component installation and focusing, and further reducing the total length of the system, which is more conducive to miniaturization.

[0076] In an exemplary embodiment, the optical lens according to the present application may satisfy: 1.5≤|F2 / F3|≤12, wherein F2 is the effective focal length of the second lens, and F3 is the effective focal length of the third lens. By controlling the optical lens to satisfy the conditional expression 1.5≤|F2 / F3|≤12, the focal lengths of the second lens and the third lens are reasonably allocated, and the focal length of the third lens is controlled to be relatively small, which is conducive to the light rays diverged by the second lens to quickly and smoothly converge to the third lens, and is conducive to a small aperture and short TTL at the rear end, and is also conducive to a smooth transition of light rays, reducing the sensitivity of the system, and improving the resolution. More specifically, F2 and F3 may further satisfy: 2.3≤|F2 / F3|≤11.2. By controlling this conditional expression, the focal lengths of the second lens and the third lens can be more reasonably allocated, which is more conducive to the light rays diverged by the second lens to quickly and smoothly converge to the third lens, and is more conducive to achieving a small aperture and short TTL at the rear end of the lens, and is also more conducive to a smooth transition of light rays, better reducing the sensitivity of the system, and improving the resolution.

[0077] In an exemplary embodiment, the optical lens according to the present application may satisfy: F / ENPD≤1.2, where F is the total effective focal length of the optical lens, and ENPD is the entrance pupil diameter of the optical lens. By controlling the optical lens to satisfy the conditional expression F / ENPD≤1.2, a small FNO of the lens may be achieved, which is beneficial to increase the light throughput. More specifically, F and ENPD may further satisfy: 0.9≤F / ENPD≤1.1. By controlling this conditional expression, it is beneficial to further achieve a small FNO of the lens, which is more beneficial to increase the light throughput.

[0078] In an exemplary embodiment, the optical lens according to the present application may satisfy: 1.5≤F / H≤2.2, wherein F is the total effective focal length of the optical lens, and H is the image height corresponding to the maximum field angle of the optical lens. By controlling the optical lens to satisfy the conditional formula 1.5≤F / H≤2.2, and reasonably controlling the ratio of the focal length and image height of the lens within a certain range, it is beneficial to improve the resolution and avoid excessively exaggerated image height or focal length causing abnormalities in the system. Reasonable image height and focal length can promote the imaging quality of the system. More specifically, F and H may further satisfy: 1.7≤F / H≤2.0. By controlling the ratio of the focal length and image height of the lens within this range, it can be more beneficial to improve the resolution, better avoid excessively exaggerated image height or focal length causing abnormalities in the system, and be more beneficial to improve the imaging quality of the system.

[0079] In an exemplary embodiment, the optical lens according to the present application may satisfy: 3≤TTL / F≤6, wherein TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional expression 3≤TTL / F≤6, it is beneficial to miniaturize the optical lens. More specifically, TTL and F may further satisfy: 4.5≤TTL / F≤5.1. By controlling this conditional expression, it is more beneficial to achieve system miniaturization, and it is also beneficial to system resolution and system sensitivity, to small FNO, and to control costs.

[0080] In an exemplary embodiment, the optical lens according to the present application may satisfy: -13≤F1 / F≤-2, wherein F1 is the effective focal length of the first lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula -13≤F1 / F≤-2, and by setting the optical focal length of the first lens to be negative, it is beneficial to the divergence of light; the first lens adopts a telephoto lens, which ensures that more light enters the optical system while allowing the light to smoothly transition to the rear optical system. More specifically, F1 and F may further satisfy: -11.8≤F1 / F≤-3.3. By controlling this conditional formula, it may be more beneficial to the divergence of light; it may be more beneficial to ensure that more light enters the optical system while allowing the light to more smoothly transition to the rear optical system.

[0081] In an exemplary embodiment, the optical lens according to the present application may satisfy: F2 / F≤-2.5, where F2 is the effective focal length of the second lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula F2 / F≤-2.5, the focal length of the second lens is reasonably allocated, which is conducive to better receiving the light entering through the first lens. The second lens is set as a telephoto lens so that the peripheral light entering through the first lens can be smoothly transitioned, which is conducive to reducing sensitivity and improving imaging quality. More specifically, F2 and F can further satisfy: -18.8≤F2 / F≤-4.1. By controlling this conditional formula, it is possible to better receive the light entering through the first lens, and the peripheral light entering through the first lens can be more smoothly transitioned, which is more conducive to reducing sensitivity and improving imaging quality. In an exemplary embodiment, the convex and concave meniscus shape of the second lens can have a tendency to approach concentric circles, and the value of F2 can tend to infinity. The second lens with negative optical power of the present application can be obtained by reasonable design. For example, in many embodiments of the present application, the effective focal length F2 of the second lens has an absolute value exceeding 100 mm. At this time, the ability of the second lens to diverge light is slightly weak, and it can mainly play the role of smoothly transitioning light.

[0082] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0<F3 / F≤3, wherein F3 is the effective focal length of the third lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional expression 0<F3 / F≤3, the focal length of the third lens is reasonably controlled to be relatively small, so that the divergent light passing through the second lens smoothly transitions to the third lens, and the light converges quickly at the third lens, which is beneficial to reducing the sensitivity of the optical system and improving the resolution; at the same time, it is also beneficial to reduce the aperture of the subsequent lens, which is beneficial to achieve short TTL and overall miniaturization. More specifically, F3 and F may further satisfy: 1.1≤F3 / F≤2.0. By controlling this conditional expression, it is more beneficial to make the divergent light passing through the second lens smoothly transition to the third lens, and the light converges more quickly at the third lens, which is more beneficial to reducing the sensitivity of the optical system and improving the resolution; at the same time, it is more beneficial to reduce the aperture of the subsequent lens, further achieve short TTL, and achieve overall miniaturization.

[0083] In an exemplary embodiment, the optical lens according to the present application may satisfy: 1.5≤|F4 / F|≤13, where F4 is the effective focal length of the fourth lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula 1.5≤|F4 / F|≤13, the focal length of the fourth lens is reasonably controlled. When the focal power of the fourth lens is positive, the convergent light passing through the third lens is further converged onto the image plane, reducing the back focus, thereby reducing the total length of the system, and at the same time, the light trend smoothly transitions to improve the image quality; when the focal power of the fourth lens is negative, the focal length of the fourth lens is reasonably controlled to be relatively large, and the light converged through the third lens is appropriately diverged in the fourth lens, which is conducive to better controlling the smooth transition of the light to the image plane, balancing the resolution of each field of view, and helping to reduce the sensitivity of the optical system and improve the imaging quality. More specifically, F4 and F may further satisfy: 1.9≤|F4 / F|≤12.4. By controlling this conditional expression, when the optical power of the fourth lens is positive, the convergent light passing through the third lens may be further converged onto the image plane, which is more conducive to reducing the back focus, thereby further reducing the total length of the system, and at the same time, the light trend transitions more smoothly, thereby further improving the image quality. When the optical power of the fourth lens is negative, the light converged through the third lens may be appropriately diverged in the fourth lens, which is conducive to better controlling the smooth transition of the light to the image plane, better balancing the resolution of each field of view, further reducing the sensitivity of the optical system, and further improving the imaging quality.

[0084] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.8≤(H / 2) / (F×tan(θ / 2))≤1.2, wherein H is the image height corresponding to the maximum field angle of the optical lens, F is the total effective focal length of the optical lens, and θ is the radian value of the maximum field angle of the optical lens. By controlling the optical lens to satisfy the conditional formula 0.8≤(H / 2) / (F×tan(θ / 2))≤1.2, the ratio of the actual image height to the ideal image height can be reasonably controlled, which is conducive to achieving a large angular resolution. More specifically, H, F and θ can further satisfy: 0.9≤(H / 2) / (F×tan(θ / 2))≤1.05. By controlling this conditional formula, it can be further conducive to achieving a large angular resolution.

[0085] In an exemplary embodiment, the optical lens according to the present application may satisfy: |R6 / R7|≥2, wherein R6 is the radius of curvature of the second side of the third lens, and R7 is the radius of curvature of the first side of the fourth lens. By controlling the optical lens to satisfy the conditional formula |R6 / R7|≥2, the radius of curvature of the second side of the third lens and the radius of curvature of the first side of the fourth lens are relatively different, which is conducive to the divergence and convergence angles offsetting each other when the light emitted from the third lens is incident on the first side of the fourth lens, thereby ensuring the focal length of the fourth lens, so that the emitted light is relatively smoothly incident on the image plane, and the tolerance sensitivity of the optical system is reduced. More specifically, R6 and R7 may further satisfy: 3.4≤|R6 / R7|≤18.0. By controlling this conditional formula, it is more conducive to the divergence and convergence angles offsetting each other when the light emitted from the third lens is incident on the first side of the fourth lens, thereby better ensuring the focal length of the fourth lens, and more conducive to making the emitted light relatively smoothly incident on the image plane, and further reducing the tolerance sensitivity of the optical system.

[0086] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0<R7 / F≤2, wherein R7 is the radius of curvature of the first side of the fourth lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula 0<R7 / F≤2, the radius of curvature of the object side of the fourth lens is controlled to be smaller, which is conducive to the rapid convergence of light, shortening the imaging distance of light, reducing the back focal length, and achieving miniaturization. More specifically, R7 and F may further satisfy: 0.7≤R7 / F≤1.4. By controlling this conditional formula, it can be more conducive to the rapid convergence of light, further shortening the imaging distance of light, and more conducive to reducing the back focal length, thereby better achieving miniaturization.

[0087] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.2≤(d2+d4) / TTL≤0.55, wherein d2 is the air spacing between the first lens and the second lens on the optical axis, d4 is the air spacing between the second lens and the third lens on the optical axis, and TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis. By controlling the optical lens to satisfy the conditional formula 0.2≤(d2+d4) / TTL≤0.55, the air spacing between the first lens and the second lens and the air spacing between the second lens and the third lens are controlled to be larger, which is beneficial to improving the imaging quality. When the air spacing between the first lens and the second lens is larger, the ghost image energy level reflected between the lenses is weaker; when the air spacing between the second lens and the third lens is larger, it is beneficial to ensure a smooth transition of light incident from a negative power lens to a positive power lens, thereby achieving low tolerance sensitivity of the optical system. More specifically, d2, d4 and TTL can further satisfy: 0.25≤(d2+d4) / TTL≤0.53. By controlling this conditional expression, it can be more conducive to improving the imaging quality; it can be more conducive to controlling the ghost image energy level reflected between lenses to be weaker; it can be more conducive to ensuring the smooth transition of light incident from the negative optical power lens to the positive optical power lens, and further realizing the low tolerance sensitivity of the optical system.

[0088] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0<R3 / F≤8, wherein R3 is the radius of curvature of the first side of the second lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula 0<R3 / F≤8, the object side of the second lens is set as a convex surface, so that the light diverging in the front can be quickly contracted and smoothly enter the rear optical system, which is conducive to reducing the system aperture and making the overall light trend of the system more stable. More specifically, R3 and F can further satisfy: 1.3≤R3 / F≤7.5. By controlling this conditional formula, it can be more conducive to quickly contracting the light diverging in the front and entering the rear optical system more smoothly, which is more conducive to reducing the system aperture and making the overall light trend of the system more stable.

[0089] In an exemplary embodiment, the optical lens according to the present application may satisfy: 1≤FOV / F≤3, wherein FOV is the maximum field of view of the optical lens, and F is the total effective focal length of the optical lens. By controlling the optical lens to satisfy the conditional formula 1≤FOV / F≤3, it is beneficial to achieve good performance when applied to long-range radars. Systems used in long-range radars have the characteristics of a small field of view and a telephoto focal length. Controlling this conditional formula is beneficial to avoiding changes caused by the influence of image height. More specifically, FOV and F may further satisfy: 1.7≤FOV / F≤2.0. By controlling this conditional formula, it is more beneficial to ensure good performance when applied to long-range radars.

[0090] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.02≤ENPD / H / FOV≤0.15, wherein ENPD is the entrance pupil diameter of the optical lens, FOV is the maximum field of view angle of the optical lens, and H is the image height corresponding to the maximum field of view angle of the optical lens. By controlling the optical lens to satisfy the conditional formula 0.02≤ENPD / H / FOV≤0.15, it can be beneficial for the lens to have the characteristics of large light transmission (large entrance pupil diameter), relatively small field of view angle, and telephoto focal length, and is particularly beneficial for the optical system to have good performance when applied to long-range radar. More specifically, ENPD, H and FOV can further satisfy: 0.05≤ENPD / H / FOV≤0.07. By controlling this conditional formula, it is more beneficial for the lens to have the characteristics of large light transmission and telephoto, and is more beneficial for the optical system to have good performance when applied to long-range radar.

[0091] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0.3≤R7 / (R8+d7)≤1.2, wherein R7 is the radius of curvature of the first side of the fourth lens, R8 is the radius of curvature of the second side of the fourth lens, and d7 is the center thickness of the fourth lens on the optical axis. By controlling the optical lens to satisfy the conditional formula 0.3≤R7 / (R8+d7)≤1.2, the fourth lens is meniscus-shaped, and the shapes of the object side and the image side are approximately concentric circles, so that the light with a large aperture at the front end can quickly enter the rear optical system, and the light trend is stable, which is conducive to reducing sensitivity and improving resolution. More specifically, R7, R8 and d7 can further satisfy: 0.4≤R7 / (R8+d7)≤0.9. By controlling this conditional formula, it can be more conducive to allowing the light with a large aperture at the front end to quickly enter the rear optical system, and the light trend is more stable, which is further conducive to reducing sensitivity and improving resolution.

[0092] In an exemplary embodiment, the optical lens according to the present application may satisfy: |R5 / R6|<1, wherein R5 is the radius of curvature of the first side of the third lens, and R6 is the radius of curvature of the second side of the third lens. By controlling the optical lens to satisfy the conditional formula |R5 / R6|<1, the object side of the third lens is convex and has a smaller radius of curvature, and the image side has a larger radius of curvature, which is conducive to the rapid convergence of light and a smooth transition to the fourth lens, so that the effective aperture of the light beam is small when the light enters the fourth lens, the rear port aperture is reduced, and the image quality is improved. More specifically, R5 and R6 may further satisfy: 0<|R5 / R6|≤0.5. By controlling this conditional formula, it can be more conducive to the rapid convergence of light and a smoother transition to the fourth lens, so that the effective aperture of the light beam is smaller when the light enters the fourth lens, the rear port aperture can be further reduced, and the image quality is further improved.

[0093] In an exemplary embodiment, the optical lens according to the present application may satisfy: 0<|R1 / R2|<3, wherein R1 is the radius of curvature of the first side of the first lens, and R2 is the radius of curvature of the second side of the first lens. By controlling the optical lens to satisfy the conditional formula 0<|R1 / R2|<3, the radius of curvature of the object side and the image side of the first lens are reasonably controlled, so that there is an optical path difference between the peripheral light and the central light, the divergent central light enters the rear optical system, and the front port diameter of the lens is reduced, the volume is reduced, and it is conducive to miniaturization and cost reduction. More specifically, R1 and R2 may further satisfy: 0<|R1 / R2|≤2.3. By controlling this conditional formula, it is more conducive to having an optical path difference between the peripheral light and the central light, the divergent central light enters the rear optical system, and it is more conducive to reducing the front port diameter of the lens, reducing the volume, and it is more conducive to miniaturization and cost reduction.

[0094] In an exemplary embodiment, the optical lens of the present application may further include a filter and / or a protective glass disposed between the fourth lens and the imaging surface as required. The filter may filter light having a specific wavelength, and the protective glass may prevent the second side element (e.g., chip) of the optical lens from being damaged.

[0095] In an exemplary embodiment, at least some of the lenses from the first lens to the fourth lens may be aspherical lenses. The present application does not specifically limit the number of spherical lenses and aspherical lenses, and the number of aspherical lenses may be increased when the focus is on the resolution quality. In particular, in order to improve the resolution quality of the optical system, the first lens, the second lens, the third lens, and the fourth lens may all be aspherical lenses. The characteristic of an aspherical lens is that the curvature changes continuously from the center of the lens to the periphery. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery, an aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting an aspherical lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality of the lens. The provision of an aspherical lens helps to correct system aberrations and improve resolution.

[0096] In an exemplary embodiment, the first lens, the second lens, the third lens and the fourth lens may all be glass lenses. An optical lens made of glass can suppress the deviation of the back focus of the optical lens with temperature changes to improve the stability of the system. At the same time, the use of glass material can avoid problems such as lens imaging blur caused by high and low temperature changes in the use environment and affecting the normal use of the lens. Specifically, when focusing on temperature performance and resolution quality, the first lens to the fourth lens may all be glass aspherical lenses. In applications where temperature stability requirements are lower, the first lens to the fourth lens in the optical lens may also be made of plastic. Using plastic to make optical lenses can effectively reduce production costs. Of course, the first lens to the fourth lens in the optical lens can also be made of a combination of plastic and glass.

[0097] According to the embodiment of the present application, the optical lens includes four lenses with optical power, which are the first to fourth lenses arranged in sequence from the first side to the second side along the optical axis, wherein the first lens has negative optical power; the second lens has negative optical power, and its first side surface is convex, and the second side surface is concave; the third lens has positive optical power, and its first side surface is convex; the fourth lens has positive optical power or negative optical power, and its first side surface is convex, and the second side surface is concave; the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula F2 / F≤-2.5; the curvature radius R3 of the first side surface of the second lens and the total effective focal length F of the optical lens satisfy the conditional formula 0<R3 / F≤8. Through this setting of the lens, the focal length of the second lens can be reasonably distributed, which is conducive to better receiving the light entering through the first lens. The second lens is set as a telephoto lens, so that the peripheral light entering through the first lens can transition smoothly, which is conducive to reducing sensitivity and improving imaging quality; with the setting that the object side of the second lens is convex, the light diverging from the front can be quickly contracted and smoothly enter the rear optical system, which is conducive to reducing the system aperture and making the overall light trend of the system smooth.

[0098] The optical lens according to the exemplary embodiment of the present application adopts a four-piece lens architecture. By reasonably setting parameters such as the lens optical power, surface shape, radius of curvature, center thickness, and air spacing between lenses on the optical axis, the optical lens can have one or more beneficial effects such as high resolution, miniaturization, and small FNO, so that the optical lens can better meet the high requirements of automotive applications such as lidar lenses.

[0099] However, it should be understood by those skilled in the art that, without departing from the technical solution claimed in the present application, the number of lenses constituting the lens can be changed to obtain the various results and advantages described in this specification. For example, although four lenses are described as an example 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. The following further describes a specific embodiment of the optical lens applicable to the above-mentioned embodiment with reference to the accompanying drawings.

[0100] Example 1

[0101] The following reference Figure 1 The optical lens according to Example 1 of the present application is described. Figure 1 A schematic structural diagram of an optical lens according to Example 1 of the present application is shown.

[0102] like Figure 1 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0103] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-concave lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is concave. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0104] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0105] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0106] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0107] Table 1 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 1. Wherein, regarding "thickness / distance", it should be understood that the thickness / distance of the row where S1 is located is the center thickness of the first lens L1, the thickness / distance of the row where S2 is located is the air spacing distance between the first lens L1 and the second lens L2, the thickness / distance of the row where S3 is located is the center thickness of the second lens L2, the thickness / distance of the row where S4 is located is the air spacing distance between the second lens L2 and the aperture STO, and so on.

[0108] Table 1

[0109]

[0110] In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are aspherical surfaces. The surface shape of the aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0111] (1)

[0112] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the cone coefficient; Ai is the correction coefficient of the i-th order of the aspheric surface. Table 2 below gives the cone coefficient k and the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspheric mirror surface S8-S9 in Example 1.

[0113] Table 2

[0114]

[0115] The MTF diagram, optical point diagram and diffraction circle energy diagram of the optical lens of this embodiment are respectively as follows: Fig.15 , Fig.16 and Fig.17 The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge of the field of view, and the diffraction circle energy parameters at 15 μm are shown in Table 31 below.

[0116] The MTF (Modulation Transfer Function) curve of an optical lens can describe the ability of the optical system to "restore" the object space on the image space. The horizontal axis of the MTF graph can be, for example, the spatial frequency. Fig.15As can be seen from Table 31, the MTF value of the optical lens of this embodiment at a spatial frequency of 50lp / mm (50 lines / mm) is 0.71, and the optical lens has a strong ability to "restore" the object space in the image space.

[0117] The optical spot diagram is a tool used to analyze the imaging quality in optical systems. For example, the distance from each point in the spot diagram to the ideal image point (usually the center of the spot diagram) can be calculated, the distances of all points are squared, the average is calculated, and finally the square root of the average is taken to obtain the RMS (Root Mean Square) value. RMS can be used to describe the size of the diffuse spot caused by the wavefront error or aberration in the optical system. The RMS radius is an important parameter for evaluating the imaging quality of the optical system, and can quantitatively reflect the actual spot size of the system. The smaller the RMS value, the smaller the image spot, the better the imaging quality of the optical system, and the smaller the aberration; the horizontal axis of the optical spot diagram can be, for example, the radius of the diffraction circle. Fig.16 As can be seen from Table 31, in the edge field of view of the optical lens of this embodiment, the root mean square radius of the light spot on the image plane is 5 μm, which is a very small value and the lens has high imaging quality.

[0118] Diffraction encircled energy can be used to describe the energy distribution of a light beam in a certain area after it passes through an optical system. Specifically, it refers to the ratio of the light intensity or energy contained in a certain radius to the total intensity or total energy in the diffraction pattern of the light beam. The optical diffraction circle can be understood as a light and dark circular pattern formed on the image plane due to the diffraction phenomenon of light when an ideal point light source is imaged through a perfect circular aperture or lens. The center of this pattern is a bright spot, called an Airy Disk, and it is surrounded by a series of light and dark alternating annular diffraction patterns, called diffraction circles. The horizontal axis of the optical diffraction encircled energy distribution diagram can be the radius of the diffraction circle, and the vertical axis can represent the percentage of encircled energy. The more encircled energy corresponding to the same radius, the more concentrated the energy and the better the performance. Fig.17 As can be seen from Table 31, within a circle with a diameter of 15 μm on the image plane, the ratio of spot energy to total light energy of the optical lens of this embodiment is 97%. It can be seen that the optical lens of this embodiment has a high resolution and good optical performance.

[0119] Therefore, according to Fig.15 , Fig.16 and Fig.17 As can be seen from Table 31, the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0120] Example 2

[0121] The following reference Figure 2 Describe the optical lens according to Example 2 of the present application. Figure 2 A schematic structural diagram of an optical lens according to Example 2 of the present application is shown.

[0122] like Figure 2 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0123] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-concave lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is concave. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0124] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0125] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0126] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0127] Table 3 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 2. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 4 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0128] Table 3

[0129]

[0130] Table 4

[0131]

[0132] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0133] Example 3

[0134] The following reference Figure 3 Describe the optical lens according to Example 3 of the present application. Figure 3 A schematic structural diagram of an optical lens according to Example 3 of the present application is shown.

[0135] like Figure 3 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0136] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a meniscus lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a meniscus lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is convex. The fourth lens L4 is a meniscus lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0137] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0138] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0139] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0140] Table 5 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 3. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 6 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0141] Table 5

[0142]

[0143] Table 6

[0144]

[0145] The MTF diagram, optical point diagram and diffraction circle energy diagram of the optical lens of this embodiment are respectively as follows: Fig.18 , Fig.19 and Fig. 20 The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge of the field of view, and the diffraction circle energy parameters at 15 μm are shown in Table 31 below.

[0146] Depend on Fig.18 As shown in Table 31, the MTF value of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm) is 0.66, and the optical lens has a strong ability to "restore" the object space in the image space. Fig.19 As shown in Table 31, in the edge field of view of the optical lens of this embodiment, the root mean square radius of the light spot on the image plane is 15 μm, which is a small value and the lens has high imaging quality. Fig. 20 As can be seen from Table 31, within a circle with a diameter of 15 μm on the image plane, the ratio of spot energy to total light energy of the optical lens of this embodiment is 94%. It can be seen that the optical lens of this embodiment has a high resolution and good optical performance.

[0147] Therefore, according to Fig.18 , Fig.19 and Fig. 20 As can be seen from Table 31, the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0148] Example 4

[0149] The following reference Figure 4 Describe the optical lens according to Example 4 of the present application. Figure 4 A schematic structural diagram of an optical lens according to Example 4 of the present application is shown.

[0150] like Figure 4As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0151] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a meniscus lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a meniscus lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is convex. The fourth lens L4 is a meniscus lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0152] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0153] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0154] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0155] Table 7 shows the curvature radius R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 4. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 8 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0156] Table 7

[0157]

[0158] Table 8

[0159]

[0160] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0161] Example 5

[0162] The following reference Figure 5 Describe the optical lens according to Example 5 of the present application. Figure 5 A schematic structural diagram of an optical lens according to Example 5 of the present application is shown.

[0163] like Figure 5 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0164] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-planar lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is flat. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0165] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0166] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0167] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0168] Table 9 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 5. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 10 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0169] Table 9

[0170]

[0171] Table 10

[0172]

[0173] The MTF diagram, optical point diagram and diffraction circle energy diagram of the optical lens of this embodiment are respectively as follows: Fig.21 , Fig. 22 and Fig.23 The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge of the field of view, and the diffraction circle energy parameters at 15 μm are shown in Table 31 below.

[0174] Depend on Fig.21 As shown in Table 31, the MTF value of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm) is 0.7, and the optical lens has a strong ability to "restore" the object space in the image space. Fig. 22 As shown in Table 31, in the edge field of view of the optical lens of this embodiment, the root mean square radius of the light spot on the image plane is 11 μm, which is a small value and the lens has high imaging quality. Fig.23 As can be seen from Table 31, within a circle with a diameter of 15 μm on the image plane, the ratio of spot energy to total light energy of the optical lens of this embodiment is 96%. It can be seen that the optical lens of this embodiment has a high resolution and good optical performance.

[0175] Therefore, according to Fig.21 , Fig. 22 and Fig.23 As can be seen from Table 31, the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0176] Example 6

[0177] The following reference Figure 6 Describe the optical lens according to Example 6 of the present application. Figure 6 A schematic structural diagram of an optical lens according to Example 6 of the present application is shown.

[0178] like Figure 6As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0179] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-planar lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is flat. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0180] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0181] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0182] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0183] Table 11 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 6. In this embodiment, the first side surface S6 of the third lens L3, the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces, and Table 12 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0184] Table 11

[0185]

[0186] Table 12

[0187]

[0188] The MTF diagram, optical point diagram and diffraction circle energy diagram of the optical lens of this embodiment are respectively as follows: Fig.24 , Fig.25 and Fig.26The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge of the field of view, and the diffraction circle energy parameters at 15 μm are shown in Table 31 below.

[0189] Depend on Fig.24 As shown in Table 31, the MTF value of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm) is 0.78, and the optical lens has a strong ability to "restore" the object space in the image space. Fig.25 As shown in Table 31, in the edge field of view of the optical lens of this embodiment, the root mean square radius of the light spot on the image plane is 4.5 μm, which is a very small value and the lens has high imaging quality. Fig.26 As can be seen from Table 31, within a circle with a diameter of 15 μm on the image plane, the ratio of spot energy to total light energy of the optical lens of this embodiment is 98%, which shows that the optical lens of this embodiment has a high resolution and good optical performance.

[0190] Therefore, according to Fig.24 , Fig.25 and Fig.26 As can be seen from Table 31, the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0191] Example 7

[0192] The following reference Figure 7 Describe the optical lens according to Example 7 of the present application. Figure 7 A schematic structural diagram of an optical lens according to Example 7 of the present application is shown.

[0193] like Figure 7 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0194] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-planar lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is flat. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0195] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0196] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0197] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0198] Table 13 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 7. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 14 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0199] Table 13

[0200]

[0201] Table 14

[0202]

[0203] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0204] Example 8

[0205] The following reference Figure 8 Describe the optical lens according to Example 8 of the present application. Figure 8 A schematic structural diagram of an optical lens according to Example 8 of the present application is shown.

[0206] like Figure 8 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0207] The first lens L1 is a concave-planar lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is flat. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-convex lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is convex. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0208] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0209] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0210] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0211] Table 15 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 8. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 16 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0212] Table 15

[0213]

[0214] Table 16

[0215]

[0216] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0217] Example 9

[0218] The following reference Fig. 9Describe the optical lens according to Example 9 of the present application. Fig. 9 A schematic structural diagram of an optical lens according to Example 9 of the present application is shown.

[0219] like Fig. 9 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0220] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-concave lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is concave. The fourth lens L4 is a convex-concave lens with negative power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0221] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0222] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0223] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0224] Table 17 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 9. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 18 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0225] Table 17

[0226]

[0227] Table 18

[0228]

[0229] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0230] Example 10

[0231] The following reference Fig.10 An optical lens according to Example 10 of the present application is described. Fig.10 A schematic structural diagram of an optical lens according to Example 10 of the present application is shown.

[0232] like Fig.10 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0233] The first lens L1 is a meniscus lens with negative power, whose first side surface S1 is concave and whose second side surface S2 is convex. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-convex lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is convex. The fourth lens L4 is a convex-concave lens with negative power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0234] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0235] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0236] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0237] Table 19 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 10. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 20 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0238] Table 19

[0239]

[0240] Table 20

[0241]

[0242] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0243] Embodiment 11

[0244] The following reference Fig.11 Describe the optical lens according to Example 11 of the present application. Fig.11 A schematic structural diagram of an optical lens according to Example 11 of the present application is shown.

[0245] like Fig.11 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0246] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is convex and whose second side surface S2 is concave. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-convex lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is convex. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0247] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0248] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0249] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0250] Table 21 shows the curvature radius R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 11. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 22 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0251] Table 21

[0252]

[0253] Table 22

[0254]

[0255] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0256] Example 12

[0257] The following reference Fig.12 Describe the optical lens according to Example 12 of the present application. Fig.12 A schematic structural diagram of an optical lens according to Example 12 of the present application is shown.

[0258] like Fig.12 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0259] The first lens L1 is a convex-concave lens with negative focal power, whose first side surface S1 is convex and whose second side surface S2 is concave. The second lens L2 is a convex-concave lens with negative focal power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-concave lens with positive focal power, whose first side surface S6 is convex and whose second side surface S7 is concave. The fourth lens L4 is a convex-concave lens with positive focal power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0260] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0261] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0262] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0263] Table 23 shows the curvature radius R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 12. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 24 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0264] Table 23

[0265]

[0266] Table 24

[0267]

[0268] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0269] Example 13

[0270] The following reference Fig.13Describe the optical lens according to Example 13 of the present application. Fig.13 A schematic structural diagram of an optical lens according to Example 13 of the present application is shown.

[0271] like Fig.13 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0272] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is convex and whose second side surface S2 is concave. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-planar lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is flat. The fourth lens L4 is a convex-concave lens with positive power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0273] In this embodiment, the third lens L3 and the fourth lens L4 are aspherical lenses. The stop STO is located between the second lens L2 and the third lens L3.

[0274] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0275] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0276] Table 25 shows the curvature radius R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 13. In this embodiment, the first side surface S6 and the second side surface S7 of the third lens L3, and the first side surface S8 and the second side surface S9 of the fourth lens L4 are all aspherical surfaces. Table 26 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S6-S7, S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0277] Table 25

[0278]

[0279] Table 26

[0280]

[0281] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0282] Embodiment 14

[0283] The following reference Fig.14 Describe the optical lens according to Example 14 of the present application. Fig.14 A schematic structural diagram of an optical lens according to Example 14 of the present application is shown.

[0284] like Fig.14 As shown, the optical lens includes a first lens L1, a second lens L2, an aperture STO, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis, and also includes, for example, a filter L5, a protective glass L6 and an image plane IMA located on the second side of the fourth lens L4.

[0285] The first lens L1 is a convex-concave lens with negative power, whose first side surface S1 is convex and whose second side surface S2 is concave. The second lens L2 is a convex-concave lens with negative power, whose first side surface S3 is convex and whose second side surface S4 is concave. The third lens L3 is a convex-concave lens with positive power, whose first side surface S6 is convex and whose second side surface S7 is concave. The fourth lens L4 is a convex-concave lens with negative power, whose first side surface S8 is convex and whose second side surface S9 is concave.

[0286] In this embodiment, the fourth lens L4 is an aspherical lens. The stop STO is located between the second lens L2 and the third lens L3.

[0287] In this embodiment, the filter L5 has, for example, a first side surface S10 and a second side surface S11 ; the protective glass L6 has, for example, a first side surface S12 and a second side surface S13 .

[0288] When the optical lens is used for photographing, light from the object passes through the surfaces S1 to S13 in sequence and is finally imaged on the imaging surface; when the optical lens is used for projection, light from the image source surface passes through the surfaces S13 to S1 in sequence and is finally projected onto the target object (not shown).

[0289] Table 27 shows the radius of curvature R, thickness / distance, refractive index Nd and Abbe number Vd of each lens of the optical lens of Example 14. In this embodiment, the first side surface S8 and the second side surface S9 of the fourth lens L4 are both aspherical surfaces, and Table 28 shows the conic coefficients and high-order coefficients of each aspherical mirror surface S8-S9 that can be used in this embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0290] Table 27

[0291]

[0292] Table 28

[0293]

[0294] The MTF parameters of the optical lens of this embodiment at a spatial frequency of 50 lp / mm (50 lines / mm), the RMS parameters of the spot diagram at the edge field of view, and the diffraction circle energy parameters at 15 μm are respectively shown in Table 31 below. According to the relevant data recorded in Table 31, it can be seen that the optical lens provided in this embodiment can achieve good imaging quality and has good optical performance.

[0295] In summary, the parameter values ​​in Examples 1 to 14 are respectively shown in Tables 29-1 and 29-2, wherein the units of F, ENPD, TTL, H, D, TL, BFL, F1, F2, F3, F4, d2, d4, d7 and d1 are all millimeters (mm), the unit of FOV is degree (°), and the unit of θ is radian.

[0296] Table 29-1

[0297]

[0298] Table 29-2

[0299]

[0300] Furthermore, Examples 1 to 14 respectively satisfy the relationships shown in Table 30-1 and Table 30-2 below.

[0301] Table 30-1

[0302]

[0303] Table 30-2

[0304]

[0305] Table 31

[0306]

[0307] The present application also provides an electronic device, which may include an optical lens according to the above-mentioned embodiment of the present application and an imaging element for converting an optical image formed by the optical lens into an electrical signal. The electronic device may be an independent electronic device such as a detection distance camera, or an imaging module integrated in a device such as a detection distance device. In addition, the electronic device may also be an independent imaging device such as a vehicle-mounted camera, or an imaging module integrated in a driving assistance system such as a vehicle-mounted camera.

[0308] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other to form a technical solution.

Claims

1. An optical lens, characterized in that: The optical lens includes, in sequence from the first side to the second side along the optical axis: a first lens having negative optical power; a second lens having negative optical power, wherein the first side surface is convex and the second side surface is concave; a third lens element having positive optical power, wherein the first side surface of the third lens element is convex; and a fourth lens having optical power, wherein the first side surface is convex and the second side surface is concave; The number of lenses having optical power in the optical lens is four; The effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: F2 / F≤-2.5; The radius of curvature R3 of the first side surface of the second lens and the total effective focal length F of the optical lens satisfy: 0<R3 / F≤8; The maximum field of view FOV of the optical lens and the total effective focal length F of the optical lens satisfy: 1≤FOV / F≤3.

2. The optical lens according to claim 1, characterized in that: The first side surface of the first lens is a concave surface, and the second side surface is a convex surface or a plane.

3. The optical lens according to claim 1, characterized in that: The first side surface of the first lens is a convex surface, and the second side surface is a concave surface.

4. The optical lens according to claim 1, characterized in that: The second side surface of the third lens is a concave surface, a flat surface or a convex surface.

5. The optical lens according to claim 1, characterized in that: The fourth lens has positive or negative refractive power.

6. The optical lens according to any one of claims 1 to 5, characterized in that: The distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, the maximum field of view FOV of the optical lens, and the image height H corresponding to the maximum field of view of the optical lens satisfy: 0.2≤TTL / H / FOV≤0.

35.

7. The optical lens according to any one of claims 1 to 5, characterized in that: The total effective focal length F of the optical lens, the arc value θ of the maximum field angle of the optical lens, and the maximum effective light aperture D of the first side surface of the first lens corresponding to the maximum field angle of the optical lens satisfy: 0.2≤(F×θ) / D≤0.

4.

8. The optical lens according to any one of claims 1 to 5, characterized in that: The total effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy: F / ENPD≤1.

2.

9. The optical lens according to any one of claims 1 to 5, characterized in that: The total effective focal length F of the optical lens and the image height H corresponding to the maximum field angle of the optical lens satisfy the following: 1.5≤F / H≤2.

2.

10. The optical lens according to any one of claims 1 to 5, characterized in that: A distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis and a total effective focal length F of the optical lens satisfy: 3≤TTL / F≤6.

11. The optical lens according to any one of claims 1 to 5, characterized in that: The effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -13≤F1 / F≤-2.

12. The optical lens according to any one of claims 1 to 5, characterized in that: The effective focal length F3 of the third lens and the total effective focal length F of the optical lens satisfy: 0<F3 / F≤3.

13. The optical lens according to any one of claims 1 to 5, characterized in that: The effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy: 1.5≤|F4 / F|≤13.

14. The optical lens according to any one of claims 1 to 5, characterized in that: The radius of curvature R7 of the first side surface of the fourth lens and the total effective focal length F of the optical lens satisfy: 0<R7 / F≤2.

15. The optical lens according to any one of claims 1 to 5, characterized in that: The air gap d2 between the first lens and the second lens on the optical axis, the air gap d4 between the second lens and the third lens on the optical axis, and the distance TTL from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis satisfy: 0.2≤(d2+d4) / TTL≤0.

55.

16. The optical lens according to any one of claims 1 to 5, characterized in that: An entrance pupil diameter ENPD of the optical lens, a maximum field of view FOV of the optical lens and an image height H corresponding to the maximum field of view of the optical lens satisfy: 0.02≤ENPD / H / FOV≤0.

15.

17. The optical lens according to any one of claims 1 to 5, characterized in that: A curvature radius R7 of a first side surface of the fourth lens, a curvature radius R8 of a second side surface of the fourth lens, and a center thickness d7 of the fourth lens on the optical axis satisfy: 0.3≤R7 / (R8+d7)≤1.

2.

18. The optical lens according to any one of claims 1 to 5, characterized in that: At least one of the following conditions is met: 4.5≤D / H / θ≤7; 0.1≤D / H / F≤0.3; 0.05≤BFL / TTL≤0.25; 1.5≤|F2 / F3|≤12; 0.8≤(H / 2) / (F×tan(θ / 2))≤1.2; |R6 / R7|≥2; |R5 / R6|<1; 0<|R1 / R2|<3; Among them, D is the maximum effective aperture of the first side surface of the first lens corresponding to the maximum field of view of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, θ is the radian value of the maximum field of view of the optical lens, F is the total effective focal length of the optical lens, TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, BFL is the distance from the center of the second side surface of the fourth lens to the imaging surface on the optical axis, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, R6 is the curvature radius of the second side surface of the third lens, R7 is the curvature radius of the first side surface of the fourth lens, R5 is the curvature radius of the first side surface of the third lens, R1 is the curvature radius of the first side surface of the first lens, and R2 is the curvature radius of the second side surface of the first lens.

19. The optical lens according to any one of claims 1 to 5, characterized in that: At least one of the following conditions is met: 0.25≤TTL / H / FOV≤0.3; 5.2≤D / H / θ≤6.8; 0.16≤D / H / F≤0.22; 0.26≤(F×θ) / D≤0.37; 0.08≤BFL / TTL≤0.22; 2.3≤|F2 / F 3|≤11.2;0.9≤F / ENPD≤1.1;1.7≤F / H≤2.0;4.5≤TTL / F≤5.1;-11.8≤F1 / F≤-3.3;-18.8≤F2 / F≤-4.1;1.1≤F3 / F≤2.0;1 .9≤|F4 / F|≤12.4; 0.9≤(H / 2) / (F×tan(θ / 2))≤1.05; 3.4≤|R6 / R7|≤18.0; 0.7≤R7 / F≤1.4; 0.25≤(d2+d4) / TTL≤0.53; 1.3≤R3 / F≤7.5; 1.7≤FOV / F≤2.0; 0.05≤ENPD / H / FOV≤0.07; 0.4≤R7 / (R8+d7)≤0.9; 0<|R5 / R6|≤0.5; 0<|R1 / R2|≤2.3; Wherein, TTL is the distance from the center of the first side surface of the first lens to the imaging surface of the optical lens on the optical axis, FOV is the maximum field of view of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, D is the maximum effective aperture of the first side surface of the first lens corresponding to the maximum field of view of the optical lens, θ is the radian value of the maximum field of view of the optical lens, F is the total effective focal length of the optical lens, BFL is the distance from the center of the second side surface of the fourth lens to the imaging surface on the optical axis, F1 is the effective focal length of the first lens, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, and F4 is the effective focal length of the fourth lens. R6 is the curvature radius of the second side surface of the third lens, R7 is the curvature radius of the first side surface of the fourth lens, d2 is the air spacing between the first lens and the second lens on the optical axis, d4 is the air spacing between the second lens and the third lens on the optical axis, R3 is the curvature radius of the first side surface of the second lens, ENPD is the entrance pupil diameter of the optical lens, R8 is the curvature radius of the second side surface of the fourth lens, d7 is the center thickness of the fourth lens on the optical axis, R5 is the curvature radius of the first side surface of the third lens, R1 is the curvature radius of the first side surface of the first lens, and R2 is the curvature radius of the second side surface of the first lens.

20. An electronic device, characterized in that: The invention comprises an optical lens according to any one of claims 1 to 19 and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

Images