Optical lens and electronic device

Abstract

The application discloses an optical lens and an electronic device comprising the same. The optical lens comprises, in order from a first side to a second side along an optical axis: a first lens having a negative refractive power; a second lens having a positive refractive power, a first side of the second lens being a convex surface and a second side of the second lens being a convex surface; a third lens having a negative refractive power, a first side of the third lens being a concave surface; and a fourth lens having a positive refractive power, a first side of the fourth lens being a convex surface and a second side of the fourth lens being a convex surface.

Description

TECHNICAL FIELD

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

[0002] With the improvement of the imaging quality of optical lenses, optical lenses have been widely used in various fields. For example, optical lenses play an irreplaceable role in intelligent detection, security monitoring, smart phones, and automotive assisted driving, etc. At the same time, in order to improve the competitiveness of their products, lens manufacturers in various fields begin to invest a lot of time and effort in the research and development of lens performance.

[0003] In recent years, with the continuous progress of image technology, optical lenses have been widely used in the field of imaging technology and the field of projection technology. In order to obtain a high-brightness imaging picture, the optical lens needs to have a strong enough light transmission capability. In order to make the projection lens achieve the customer's satisfactory bright lighting effect, the projection lens needs to have the maximum light flux, that is, the F number design requirement of the lens will be smaller, and it also needs to ensure that the color edge of the projection surface is small. However, most of the optical lenses on the market often lead to a decrease in imaging quality on the basis of ensuring the light flux of the lens.

[0004] In addition, in order to meet the requirements of miniaturized electronic devices, optical devices equipped with optical lenses are becoming more and more miniaturized, therefore, the miniaturization of optical lenses is also crucial. At the same time, in order to reduce image distortion, the telecentric design of the lens is also crucial. SUMMARY

[0005] The present application provides an optical lens, which comprises, in order from a first side to a second side along an optical axis: a first lens having a negative focal power; a second lens having a positive focal power, a first side of which is a convex surface and a second side of which is a convex surface; a third lens having a negative focal power, a first side of which is a concave surface; and a fourth lens having a positive focal power, a first side of which is a convex surface and a second side of which is a convex surface.

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

[0007] In one embodiment, a second side of the third lens is a concave surface or a convex surface.

[0008] In one embodiment, the third lens and the fourth lens are cemented to form a cemented lens.

[0009] In one embodiment, a total length TTL 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 can satisfy: TTL / H / FOV≤0.35.

[0010] In an embodiment, a total track length TTL of the optical lens and a total effective focal length F of the optical lens can satisfy: TTL / F≤5.

[0011] In an embodiment, a total effective focal length F of the optical lens and a maximum light passing aperture D of the first side surface of the first lens corresponding to a maximum field of view angle of the optical lens can satisfy: 0.2≤F / D≤2.

[0012] In an embodiment, a maximum field of view angle FOV of the optical lens, a maximum light passing aperture D of the first side surface of the first lens corresponding to a maximum field of view angle of the optical lens, and an image height H corresponding to the maximum field of view angle of the optical lens can satisfy: D / H / FOV≤0.05.

[0013] In an embodiment, a back focal length BFL of the optical lens and a total track length TTL of the optical lens can satisfy: BFL / TTL≥0.35.

[0014] In an embodiment, a maximum half field of view angle HFOV of the optical lens and a total effective focal length F of the optical lens can satisfy: F*TAN(HFOV)≥2mm.

[0015] In an embodiment, a total effective focal length F of the optical lens and a central curvature radius R1 of the first side surface of the first lens can satisfy: |R1 / F|≥1.

[0016] In an embodiment, a total effective focal length F of the optical lens and a central curvature radius R4 of the first side surface of the second lens can satisfy: R4 / F≥1.5.

[0017] In an embodiment, a total effective focal length F of the optical lens, a central curvature radius R4 of the first side surface of the second lens, and a central curvature radius R5 of the second side surface of the second lens can satisfy: |F / R4|+|F / R5|≤5.

[0018] In an embodiment, a central curvature radius R2 of the second side surface of the first lens and a central curvature radius R4 of the first side surface of the second lens can satisfy: -1≤(R2-R4) / (R2+R4)≤-0.2.

[0019] In an embodiment, a central thickness d1 of the first lens on the optical axis and a central thickness d2 of the second lens on the optical axis can satisfy: d2 / d1≥3.

[0020] In an embodiment, a distance TL of the first side surface of the first lens to the second side surface of the fourth lens on the optical axis and a central thickness d4 of the fourth lens on the optical axis can satisfy: TL / d4≤5.

[0021] In an embodiment, the effective focal length F1 of the first lens and the effective focal length F2 of the second lens can satisfy: |F2 / F1|≤4.

[0022] In an embodiment, the effective focal length F1 of the first lens and the effective focal length F3 of the third lens can satisfy: F1 / F3≤2.

[0023] In an embodiment, the effective focal length F3 of the third lens and the total effective focal length F of the optical lens can satisfy: 1≤|F3 / F|≤5.

[0024] In an embodiment, the effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens can satisfy: F4 / F≤5.

[0025] In an embodiment, the effective focal length F3 of the third lens and the effective focal length F4 of the fourth lens can satisfy: |F3 / F4|≥1.

[0026] In an embodiment, the combined focal length F34 of the third lens and the fourth lens and the total effective focal length F of the optical lens can satisfy: F34 / F≤6.

[0027] In an embodiment, the maximum light-passing aperture D4 of the first side surface of the fourth lens corresponding to the maximum field angle of the optical lens and the distance TL on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens can satisfy: D4 / TL≥0.5.

[0028] In an embodiment, the maximum light-passing aperture D4 of the first side surface of the fourth lens corresponding to the maximum field angle of the optical lens and the total length TTL of the optical lens can satisfy: D4 / TTL≥0.25.

[0029] In an embodiment, the maximum light-passing aperture D3 of the first side surface of the third lens corresponding to the maximum field angle of the optical lens and the distance TL on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens can satisfy: D3 / TL≥0.5.

[0030] In an embodiment, the maximum light-passing aperture D3 of the first side surface of the third lens corresponding to the maximum field angle of the optical lens and the total length TTL of the optical lens can satisfy: D3 / TTL≥0.25.

[0031] In an embodiment, the Abbe number Vd3 of the third lens and the Abbe number Vd4 of the fourth lens can satisfy: Vd4 / Vd3≥1.6.

[0032] According to an aspect of the present application, an optical lens is provided. The optical lens comprises, in order from a first side to a second side along an optical axis, a first lens having a negative focal power, a second lens having a positive focal power, a third lens having a negative focal power, and a fourth lens having a positive focal power. A maximum field of view of the optical lens corresponds to a maximum entrance aperture D4 of a first side surface of the fourth lens and a distance TL on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens satisfying D4 / TL≥0.3.

[0033] In one embodiment, the first side surface of the first lens is convex, and the second side surface of the first lens is concave.

[0034] In one embodiment, the first side surface of the first lens is concave, and the second side surface of the first lens is concave.

[0035] In one embodiment, the first side surface of the second lens is convex, and the second side surface of the second lens is convex.

[0036] In one embodiment, the first side surface of the third lens is concave, and the second side surface of the third lens is concave or convex.

[0037] In one embodiment, the first side surface of the fourth lens is convex, and the second side surface of the fourth lens is convex.

[0038] In one embodiment, the third lens and the fourth lens are cemented to form a cemented lens.

[0039] In one embodiment, a total length TTL 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 TTL / H / FOV≤0.35.

[0040] In one embodiment, a total length TTL of the optical lens and a total effective focal length F of the optical lens satisfy TTL / F≤5.

[0041] In one embodiment, a total effective focal length F of the optical lens and a maximum entrance aperture D of the first side surface of the first lens corresponding to the maximum field of view of the optical lens satisfy 0.2≤F / D≤2.

[0042] In one embodiment, a maximum field of view FOV of the optical lens, a maximum entrance aperture D of the first side surface of the first lens corresponding to the maximum field of view of the optical lens, and an image height H corresponding to the maximum field of view of the optical lens satisfy D / H / FOV≤0.05.

[0043] In one embodiment, a back focal length BFL of the optical lens and a total length TTL of the optical lens satisfy BFL / TTL≥0.35.

[0044] In an embodiment, a maximum half field of view HFOV of the optical lens and a total effective focal length F of the optical lens can satisfy: F*TAN(HFOV)≥2mm.

[0045] In an embodiment, a total effective focal length F of the optical lens and a central curvature radius R1 of the first side surface of the first lens can satisfy: |R1 / F|≥1.

[0046] In an embodiment, a total effective focal length F of the optical lens and a central curvature radius R4 of the first side surface of the second lens can satisfy: R4 / F≥1.5.

[0047] In an embodiment, a total effective focal length F of the optical lens, a central curvature radius R4 of the first side surface of the second lens, and a central curvature radius R5 of the second side surface of the second lens can satisfy: |F / R4|+|F / R5|≤5.

[0048] In an embodiment, a central curvature radius R2 of the second side surface of the first lens and a central curvature radius R4 of the first side surface of the second lens can satisfy: -1≤(R2-R4) / (R2+R4)≤-0.2.

[0049] In an embodiment, a central thickness d1 of the first lens on the optical axis and a central thickness d2 of the second lens on the optical axis can satisfy: d2 / d1≥3.

[0050] In an embodiment, a distance TL of the first side surface of the first lens to the second side surface of the fourth lens on the optical axis and a central thickness d4 of the fourth lens on the optical axis can satisfy: TL / d4≤5.

[0051] In an embodiment, an effective focal length F1 of the first lens and an effective focal length F2 of the second lens can satisfy: |F2 / F1|≤4.

[0052] In an embodiment, an effective focal length F1 of the first lens and an effective focal length F3 of the third lens can satisfy: F1 / F3≤2.

[0053] In an embodiment, an effective focal length F3 of the third lens and a total effective focal length F of the optical lens can satisfy: 1≤|F3 / F|≤5.

[0054] In an embodiment, an effective focal length F4 of the fourth lens and a total effective focal length F of the optical lens can satisfy: F4 / F≤5.

[0055] In an embodiment, an effective focal length F3 of the third lens and an effective focal length F4 of the fourth lens can satisfy: |F3 / F4|≥1.

[0056] In an embodiment, a combined focal length F34 of the third lens and the fourth lens and a total effective focal length F of the optical lens can satisfy: F34 / F≤6.

[0057] In an embodiment, a maximum light passing aperture D4 of the first side surface of the fourth lens corresponding to a maximum field angle of the optical lens and a total length TTL of the optical lens can satisfy: D4 / TTL≥0.25.

[0058] In an embodiment, a maximum light passing aperture D3 of the first side surface of the third lens corresponding to a maximum field angle of the optical lens and a distance TL of the first side surface of the first lens to the second side surface of the fourth lens on the optical axis can satisfy: D3 / TL≥0.5.

[0059] In an embodiment, a maximum light passing aperture D3 of the first side surface of the third lens corresponding to a maximum field angle of the optical lens and a total length TTL of the optical lens can satisfy: D3 / TTL≥0.25.

[0060] In an embodiment, an Abbe number Vd3 of the third lens and an Abbe number Vd4 of the fourth lens can satisfy: Vd4 / Vd3≥1.6.

[0061] In an embodiment, a maximum light passing aperture D4 of the first side surface of the fourth lens corresponding to a maximum field angle of the optical lens and a distance TL of the first side surface of the first lens to the second side surface of the fourth lens on the optical axis can satisfy: D4 / TL≥0.5.

[0062] Another aspect of the present application provides an electronic device. The electronic device comprises the optical lens provided by the present application and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

[0063] The present application adopts four lenses, and by optimizing the shape, optical power, etc. of each lens, the optical lens has at least one of the following beneficial effects: small FNO, large light passing amount, telecentricity on the image side, small chromatic aberration, miniaturization, back focal length, low cost, high resolution, etc. BRIEF DESCRIPTION OF DRAWINGS

[0064] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of the embodiments when read in conjunction with the accompanying drawings. In the drawings:

[0065] Figure 1 FIG. 1 is a structure schematic diagram of an optical lens according to an embodiment of the present application;

[0066] Figure 2 FIG. 2 is a structure schematic diagram of an optical lens according to another embodiment of the present application;

[0067] Figure 3FIG. 1 shows a schematic diagram of an optical lens according to Embodiment 1 of the present application;

[0068] Figure 4 FIG. 2 shows a schematic diagram of an optical lens according to Embodiment 2 of the present application;

[0069] Figure 5 FIG. 3 shows a schematic diagram of an optical lens according to Embodiment 3 of the present application;

[0070] Figure 6 FIG. 4 shows a schematic diagram of an optical lens according to Embodiment 4 of the present application;

[0071] Figure 7 FIG. 5 shows a schematic diagram of an optical lens according to Embodiment 5 of the present application; and

[0072] Figure 8 FIG. 6 shows a schematic diagram of an optical lens according to Embodiment 6 of the present application. DETAILED DESCRIPTION

[0073] For the purposes of promoting an understanding of the principles of the application, reference will now be made to the embodiments illustrated in the drawings. It is expressly understood that the drawings are only exemplary and are therefore not intended as a definition of the limits of the application. In this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items. The term "coupled" is used herein to express either an indirect or direct electrical connection between two or more elements.

[0074] It should be noted that the terms first, second, third, etc. are used herein only to distinguish one element from another and do not imply any limitation on the features. Thus, a first lens discussed below could also be termed a second lens or a third lens without departing from the teachings of the present application.

[0075] In the drawings, the thickness, size, and shape of lenses have been exaggerated slightly for the sake of explanation. Specifically, the shape of a spherical surface or an aspherical surface shown in the drawings is shown by way of example. That is, the shape of a spherical surface or an aspherical surface is not limited to the shape of a spherical surface or an aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0076] In the present disclosure, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the first side is referred to as the first side surface of the lens, and the surface of each lens closest to the second side is referred to as the second side surface of the lens. The surface of the optical lens closest to the second side is referred to as the second side surface of the optical lens. For example, the first side can be the object side, and the second side can be the image side. Alternatively, the first side can be the imaging side, and the second side can be the image source side.

[0077] It should also be understood that the use of the terms "including", "including having", "having", "containing", and / or "containing having" when used in this specification intends existence of the stated features, elements and / or components, but does 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 items, it modifies the entire list of items and not the individual items in the list. Furthermore, when describing embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the term "exemplary" is intended to mean an example or an illustration.

[0078] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that the terms should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0079] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0080] The features, principles, and other aspects of the present application are described in detail below.

[0081] In exemplary embodiments, the optical lens includes, for example, four lenses with optical power, i.e., a first lens, a second lens, a third lens, and a fourth lens. The four lenses are arranged in order along the optical axis from the first side to the second side.

[0082] In exemplary embodiments, the optical lens provided by the present application can be used as, for example, an imaging lens. In this case, the first side of the optical lens can be the object side, and the second side can be the image side. Light rays from the object side can be imaged on the image side. The second side surface of the optical lens is the imaging surface of the optical lens.

[0083] In example embodiments, the optical lens provided by the present application can be used as, for example, a smart headlamp lens, i.e., a projection lens. In this case, the second side of the optical lens can be an image source side, and the first side can be an imaging side. Light from the image source side can be imaged at the imaging side. The second side of the optical lens is an image source side of the optical lens.

[0084] In example embodiments, the optical lens can further include a light sensing element disposed on the second side. Optionally, the light sensing element disposed on the second side can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS).

[0085] For the convenience of description, the beneficial effects of the optical lens when used as an imaging lens are mainly described in detail below. It should be understood that, when the optical lens is used as, for example, a smart headlamp lens, i.e., a projection lens, the beneficial effects of the optical lens when used as a projection lens can be inferred according to the principle of reversibility of the optical path.

[0086] In example embodiments, the first lens can have a negative focal power. The first lens can have a convex-concave surface type or a concave-concave surface type. Such a focal power and surface type of the first lens are beneficial for the entry of light rays at a large angle into the optical lens, and the concave image side surface of the first lens is beneficial for further diverging the light rays and increasing the light aperture and the amount of light. For example, the optical lens according to the present application can satisfy |F1 / F|≤7, where F1 is the effective focal length of the first lens, and F is the total effective focal length of the optical lens. More specifically, F1 and F can further satisfy |F1 / F|≤5.

[0087] In example embodiments, the second lens can have a positive focal power. The second lens can have a convex-convex surface type. The second lens having a positive focal power and a convex object side surface is beneficial for balancing the spherical aberration generated by the first lens, and the convex image side surface of the second lens is beneficial for reducing the angle of the light rays exiting from the second lens and smoothly transitioning the light rays to the rear optical lens. For example, the second lens can be made of a high refractive index material, which is beneficial for compensating for on-axis aberrations and improving the imaging quality. For example, the refractive index Nd2 of the second lens can be greater than or equal to 1.65. For example, the optical lens according to the present application can satisfy |F2 / F|≤7, where F2 is the effective focal length of the second lens, and F is the total effective focal length of the optical lens. More specifically, F2 and F can further satisfy |F2 / F|≤5.

[0088] In example embodiments, the third lens can have a negative focal power. The third lens can have a concave-concave surface type or a concave-convex surface type. The third lens having a negative focal power and a concave object side surface is beneficial for further diverging the light rays converged by the second lens, increasing the edge energy of the pupil, and improving the relative luminance. The concave or convex image side surface of the third lens is beneficial for smoothly transitioning the light rays to the fourth lens and reducing the sensitivity of the lens.

[0089] In exemplary embodiments, the fourth lens can have positive refractive power. The fourth lens can have a convex-convex surface shape. The fourth lens has positive refractive power and a convex image-side surface, which can effectively compress light rays, be beneficial to compact the light beam, reduce the CRA, be beneficial to make the optical lens telecentric in the image space, be beneficial to compensate the spherical aberration generated by the object-side surface of the third lens, and improve the imaging quality.

[0090] In exemplary embodiments, a diaphragm for limiting the light beam can be arranged between the first lens and the second lens to further improve the imaging quality of the optical lens. Arranging the diaphragm between the first lens and the second lens can be beneficial to effectively compact the light rays entering the optical lens, be beneficial to make the optical lens telecentric in the image space, and be beneficial to reduce the assembly sensitivity of the optical lens. In embodiments of the present application, the diaphragm can be arranged near the second side surface of the first lens; of course, the diaphragm can also be arranged near the first side surface of the second lens. However, it should be noted that the position of the diaphragm disclosed herein is only an example and not a limitation; in alternative embodiments, the diaphragm can also be arranged at other positions according to actual needs.

[0091] In exemplary embodiments, the total track length TTL of the optical lens according to the present application can be the distance from the center of the first side surface of the first lens to the second side surface of the optical lens on the optical axis. The back focal length BFL of the optical lens according to the present application can be the distance from the center of the second side surface of the fourth lens to the second side surface of the optical lens on the optical axis.

[0092] In exemplary embodiments, the optical lens according to the present application can satisfy TTL / H / FOV≤0.35, where TTL is the total track length 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. More specifically, TTL, H and FOV can further satisfy TTL / H / FOV≤0.25. Satisfying TTL / H / FOV≤0.35 is beneficial to realize miniaturization of the optical lens.

[0093] In exemplary embodiments, the optical lens according to the present application can satisfy TTL / F≤5, where TTL is the total track length of the optical lens, and F is the total effective focal length of the optical lens. More specifically, TTL and F can further satisfy TTL / F≤4.5. Satisfying TTL / F≤5 is beneficial to realize miniaturization of the optical lens.

[0094] In exemplary embodiments, the optical lens according to the present application can satisfy: 0.2≤F / D≤2, where F is the total effective focal length of the optical lens, and D is the maximum light passing aperture of the first side of the first lens corresponding to the maximum field of view angle of the optical lens. More specifically, F and D can further satisfy: 0.5≤F / D≤1.7. Satisfying 0.2≤F / D≤2 is conducive to making the front end aperture of the lens smaller and ensuring the light passing amount of the lens.

[0095] In exemplary embodiments, the optical lens according to the present application can satisfy: D / H / FOV≤0.05, where FOV is the maximum field of view angle of the optical lens, D is the maximum light passing aperture of the first side of the first lens corresponding to 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. More specifically, D, H and FOV can further satisfy: D / H / FOV≤0.045. Satisfying D / H / FOV≤0.05 is conducive to making the front end aperture of the lens smaller and realizing the miniaturization of the lens.

[0096] In exemplary embodiments, the optical lens according to the present application can satisfy: BFL / TTL≥0.35, where BFL is the back focal length of the optical lens, and TTL is the total length of the optical lens. More specifically, BFL and TTL can further satisfy: BFL / TTL≥0.4. Satisfying BFL / TTL≥0.35 is conducive to making the back focal length BFL of the optical lens longer, reserving space for the installation and focusing of the optical assembly, and avoiding interference of the assembly.

[0097] In exemplary embodiments, the optical lens according to the present application can satisfy: F×TAN(HFOV)≥2mm, where HFOV is the maximum half field of view angle of the optical lens, and F is the total effective focal length of the optical lens. More specifically, F and HFOV can further satisfy: F×TAN(HFOV)≥3mm. Satisfying F×TAN(HFOV)≥2mm is conducive to making the first side light deflection angle of the optical lens larger, which can effectively compress the size of the lens and realize miniaturization.

[0098] In exemplary embodiments, the optical lens according to the present application can satisfy: |R1 / F|≥1, where F is the total effective focal length of the optical lens, and R1 is the center curvature radius of the first side of the first lens. More specifically, R1 and F can further satisfy: |R1 / F|≥1.1, and R1 and F can further satisfy: |R1 / F|≥2. Satisfying |R1 / F|≥1 is conducive to making the refraction angle of the incident light change more gently, avoiding too much aberration caused by too strong refraction change, and facilitating the manufacture of the first lens, while reducing the tolerance sensitivity of the lens.

[0099] In exemplary embodiments, the optical lens according to the present application can satisfy: R4 / F≥1.5, where F is the total effective focal length of the optical lens, and R4 is the central radius of curvature of the first side surface of the second lens. More specifically, R4 and F can further satisfy: R4 / F≥2. Satisfying R4 / F≥1.5 is conducive to improving the ability of the second lens to control the deflection of light rays, making the light rays transition smoothly, and is conducive to making the back focal length larger, while being conducive to lens bearing and assembly.

[0100] In exemplary embodiments, the optical lens according to the present application can satisfy: |F / R4|+|F / R5|≤5, where F is the total effective focal length of the optical lens, R4 is the central radius of curvature of the first side surface of the second lens, and R5 is the central radius of curvature of the second side surface of the second lens. More specifically, F, R4 and R5 can further satisfy: |F / R4|+|F / R5|≤3.5. Satisfying |F / R4|+|F / R5|≤5 can assist the incident light rays to enter the optical lens and can effectively correct chromatic aberration to improve the imaging quality.

[0101] In exemplary embodiments, the optical lens according to the present application can satisfy: -1≤(R2-R4) / (R2+R4)≤-0.2, where R2 is the central radius of curvature of the second side surface of the first lens, and R4 is the central radius of curvature of the first side surface of the second lens. More specifically, R2 and R4 can further satisfy: -0.9≤(R2-R4) / (R2+R4)≤-0.3. Satisfying -1≤(R2-R4) / (R2+R4)≤-0.2 can correct the aberration of the optical lens and is conducive to ensuring that the light rays emitted from the first lens are incident to the first side surface of the second lens when the incident light rays are relatively smooth, thereby reducing the tolerance sensitivity of the optical lens.

[0102] In exemplary embodiments, the optical lens according to the present application can satisfy: d2 / d1≥3, where d1 is the central thickness of the first lens on the optical axis, i.e., the distance from the center of the first side surface to the center of the second side surface of the first lens, and d2 is the central thickness of the second lens on the optical axis, i.e., the distance from the center of the first side surface to the center of the second side surface of the second lens. More specifically, d2 and d1 can further satisfy: d2 / d1≥4. Satisfying d2 / d1≥3 is conducive to controlling the light ray trend, making the light rays transition smoothly, and is conducive to improving the resolving power.

[0103] In exemplary embodiments, the optical lens according to the present application can satisfy: TL / d4≤5, where TL is the distance on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens, and d4 is the center thickness on the optical axis of the fourth lens, i.e., the distance from the first side surface center to the second side surface center of the fourth lens. More specifically, TL and d4 can further satisfy: TL / d4≤4.5. Satisfying TL / d4≤5 is beneficial to increase the light collecting ability of the fourth lens and ensure the light flux.

[0104] In exemplary embodiments, the optical lens according to the present application can satisfy: |F2 / F1|≤4, where F1 is the effective focal length of the first lens, and F2 is the effective focal length of the second lens. More specifically, F2 and F1 can further satisfy: |F2 / F1|≤3. Satisfying |F2 / F1|≤4 is beneficial to control the light path, make the light transition gently, and improve the resolving power.

[0105] In exemplary embodiments, the optical lens according to the present application can satisfy: F1 / F3≤2, where F1 is the effective focal length of the first lens, and F3 is the effective focal length of the third lens. More specifically, F1 and F3 can further satisfy: F1 / F3≤1.5. Satisfying F1 / F3≤2 is beneficial to make the large-angle light enter the optical lens and make the first lens and the third lens converge the light, thereby ensuring the light flux.

[0106] In exemplary embodiments, the optical lens according to the present application can satisfy: 1≤|F3 / F|≤5, where F3 is the effective focal length of the third lens, and F is the total effective focal length of the optical lens. More specifically, F3 and F can further satisfy: 1.3≤|F3 / F|≤4.5. Satisfying 1≤|F3 / F|≤5 is beneficial to make the light change gently after passing through the third lens, thereby making the light transition gently.

[0107] In exemplary embodiments, the optical lens according to the present application can satisfy: F4 / F≤5, where F4 is the effective focal length of the fourth lens, and F is the total effective focal length of the optical lens. More specifically, F4 and F can further satisfy: F4 / F≤4. Satisfying F4 / F≤5 is beneficial to make the fourth lens converge the light and ensure the light flux.

[0108] In exemplary embodiments, the optical lens according to the present application can satisfy: |F3 / F4|≥1, where F3 is the effective focal length of the third lens, and F4 is the effective focal length of the fourth lens. More specifically, F3 and F4 can further satisfy: 1≤|F3 / F4|≤2. Satisfying |F3 / F4|≥1 is beneficial to make the light transition gently, reduce the sensitivity, and effectively improve the lens thermal compensation and improve the image quality.

[0109] In an exemplary embodiment, the optical lens according to the present application may satisfy the following conditions: F34 / F≤6, where F34 is the combined focal length of the third and fourth lenses, and F is the total effective focal length of the optical lens. More specifically, F34 and F may further satisfy the following conditions: F34 / F≤5. Meeting F34 / F≤6 helps reduce aberrations caused by light entering through the third lens, while also improving the lens's resolving power.

[0110] In exemplary embodiments, the optical lens according to the present application may satisfy the following conditions: D4 / TL ≥ 0.3, where D4 is the maximum clear aperture of the first side surface of the fourth lens corresponding to the maximum field of view of the optical lens, and TL is the distance on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens. More specifically, D4 and TL may further satisfy the following conditions: D4 / TL ≥ 0.5, and D4 and TL may further satisfy the following conditions: D4 / TL ≥ 0.6. Meeting D4 / TL ≥ 0.3 helps increase the clear aperture of the fourth lens, resulting in a larger light-collecting aperture angle on the second side surface of the fourth lens and stronger light-collecting capability.

[0111] In an exemplary embodiment, the optical lens according to the present application may satisfy the following conditions: D4 / TTL ≥ 0.25, where D4 is the maximum clear aperture of the first side surface of the fourth lens element corresponding to the maximum field of view of the optical lens, and TTL is the total length of the optical lens element. More specifically, D4 and TTL may further satisfy the following conditions: D4 / TTL ≥ 0.3. Meeting D4 / TTL ≥ 0.25 increases the clear aperture of the fourth lens element, resulting in a larger light-collecting angle on the second side surface of the fourth lens element, and thus a stronger light-collecting capability.

[0112] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: D3 / TL ≥ 0.5, where D3 is the maximum clear aperture of the first side surface of the third lens corresponding to the maximum field of view of the optical lens, and TL is the distance on the optical axis from the first side surface of the first lens to the second side surface of the fourth lens. More specifically, D3 and TL may further satisfy the following relationship: D3 / TL ≥ 0.6. Meeting D3 / TL ≥ 0.5 helps increase the clear aperture of the third lens, resulting in a larger light-collecting aperture angle on the second side surface of the third lens and stronger light-collecting capability.

[0113] In an exemplary embodiment, the optical lens according to the present application may satisfy the following conditions: D3 / TTL ≥ 0.25, where D3 is the maximum clear aperture of the first side of the third lens element corresponding to the maximum field of view of the optical lens, and TTL is the total length of the optical lens. More specifically, D3 and TTL may further satisfy the following conditions: D3 / TTL ≥ 0.3. Meeting D3 / TTL ≥ 0.25 increases the clear aperture of the third lens element, resulting in a larger light-collecting angle on the second side of the third lens element, and thus a stronger light-collecting capability.

[0114] In an exemplary embodiment, the optical lens according to the present application can satisfy: Vd4 / Vd3≥1.6, wherein Vd3 is the Abbe number of the third lens, and Vd4 is the Abbe number of the fourth lens. More specifically, Vd4 and Vd3 can further satisfy: Vd4 / Vd3≥2. Satisfying Vd4 / Vd3≥1.6 is conducive to eliminating chromatic aberration of the lens.

[0115] In an exemplary embodiment, the optical lens according to the present application can further include a filter and / or a protective glass disposed between the fourth lens and the second side of the optical lens, as needed, to filter light rays with different wavelengths and prevent damage to the second side element (e.g., a chip) of the optical lens.

[0116] As known by those skilled in the art, cemented lenses can be used to minimize or eliminate chromatic aberration. The use of cemented lenses in optical lenses can improve image quality, reduce reflection loss of light energy, thereby achieving high resolution and improving the clarity of lens imaging. In addition, the use of cemented lenses can also simplify the assembly procedure in the lens manufacturing process.

[0117] In an exemplary embodiment, the third lens and the fourth lens can be cemented to form a cemented lens. Cementing the third lens with negative optical power and concave on both object side and image side, and the fourth lens with positive optical power and convex on both object side and image side, can smoothly transition the light emitted by the front lens to the second side of the optical lens, which is conducive to making the optical lens compact in structure, reducing the size of the optical lens, correcting various aberrations of the optical lens, reducing the matching sensitivity of each lens, improving the resolution, and optimizing the optical performance such as distortion, CRA, etc. Of course, the third lens and the fourth lens can also not be cemented, which is conducive to eliminating chromatic aberration and improving resolution.

[0118] The cemented manner between the above lenses has at least one of the following advantages: reducing self-chromatic aberration, reducing tolerance sensitivity, balancing the overall chromatic aberration of the system through residual partial chromatic aberration; reducing the spacing distance between the two lenses, thereby reducing the total length of the system; reducing the assembly components between the lenses, thereby reducing the process and cost; reducing the tilt / offset core tolerance sensitivity problem of the lens unit caused in the assembly process, improving the production yield; reducing the light loss caused by reflection between the lenses, improving the illumination; further reducing the field curvature and correcting the off-axis point aberration of the system. Such cemented design shares the overall chromatic aberration correction of the system, effectively corrects aberration to improve resolution, and makes the optical system compact as a whole, meeting the miniaturization requirement. The cemented lens provided by the present application is composed of a negative lens (third lens) and a positive lens (fourth lens), which can further converge light to the second side of the optical lens, wherein the positive lens can have a lower refractive index, and the negative lens can have a higher refractive index to eliminate chromatic aberration (relative to the positive lens).

[0119] In the example embodiments, the first lens to the fourth lens can be a spherical lens or an aspherical lens. For example, the first lens, the third lens and the fourth lens can be aspherical lenses; and the second lens can be a spherical lens. The present application does not specifically limit the specific number of the spherical lens and the aspherical lens. When the imaging quality is emphasized, the number of the aspherical lens can be increased. In particular, in order to improve the resolving power of the optical system, the first lens, the second lens, the third lens and the fourth lens can all be aspherical lenses. The aspherical lens has the characteristic that the curvature is continuously changed from the center of the lens to the periphery. Unlike the spherical lens which has a constant curvature from the center of the lens to the periphery, the aspherical lens has better curvature radius characteristics, and has the advantages of improving the distortion aberration and improving the astigmatism aberration. After the aspherical lens is used, the aberration that occurs during imaging can be eliminated as much as possible, thereby improving the imaging quality of the lens. The arrangement of the aspherical lens helps to correct the system aberration and improve the resolving power.

[0120] The optical lens according to the above-mentioned embodiments of the present application has at least one of the beneficial effects of small FNO (which can be less than or equal to 1.9), large light flux, telecentricity on the image side, small chromatic aberration, miniaturization, long back focal length, low cost, high resolving power and good imaging quality, etc. by reasonable arrangement of the shapes and optical powers of the lenses.

[0121] When the optical lens is used for projection, by reasonably arranging the effective focal lengths of the lenses, it is beneficial to make the angle of the light rays incident to the lens from the chip smaller, so as to meet the design of telecentricity on the image side and ensure that the projection lens collects as much light flux as possible. The optical lens can also realize miniaturization of the lens while meeting the long back focal length, which is convenient for assembly in limited space in some special fields; four lenses are used, which can be low in cost; by arranging the third lens and the fourth lens to have negative optical power and positive optical power respectively, the chromatic aberration of the lens can be reduced, so as to meet the requirement of small color fringe on the projection imaging surface.

[0122] In the example embodiments, the first lens, the second lens, the third lens and the fourth lens can all be glass lenses. The optical lens made of glass can suppress the shift of the back focal length of the optical lens with the change of temperature, so as to improve the system stability. At the same time, the use of glass material can avoid the imaging blur of the lens caused by the change of high and low temperature in the use environment, which affects the normal use of the lens. Specifically, when the resolving power and reliability are emphasized, the first lens to the fourth lens can all be glass aspherical lenses. Of course, in the application occasions where the temperature stability requirement is low, the first lens to the fourth lens in the optical lens can also be made of plastic. The optical lens made of plastic can effectively reduce the manufacturing cost. Of course, the first lens to the fourth lens in the optical lens can also be made of plastic and glass.

[0123] However, those skilled in the art will understand that the number of lenses constituting the lens can be changed without departing from the technical solutions claimed in the present application to obtain the various results and advantages described in the specification. For example, although described in the embodiments by way of example with four lenses, the optical lens is not limited to including four lenses. If necessary, the optical lens can also include other numbers of lenses. Specific embodiments of the optical lens applicable to the above embodiments are further described below with reference to the accompanying drawings.

[0124] Example 1

[0125] The following refers to Figure 1 An optical lens according to Embodiment 1 of the present application is described. Figure 1 A structural schematic diagram of the optical lens according to Embodiment 1 of the present application is shown.

[0126] As Figure 1 shown, the optical lens sequentially includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4 from the first side to the second side along the optical axis.

[0127] The first lens L1 is a convex-concave lens with negative optical power, the first side S1 thereof is a convex surface, and the second side S2 thereof is a concave surface. The second lens L2 is a double-convex lens with positive optical power, the first side S4 thereof is a convex surface, and the second side S5 thereof is a convex surface. The third lens L3 is a double-concave lens with negative optical power, the first side S6 thereof is a concave surface, and the second side S7 thereof is a concave surface. The fourth lens L4 is a double-convex lens with positive optical power, the first side S7 thereof is a convex surface, and the second side S8 thereof is a convex surface. The third lens L3 and the fourth lens L4 are cemented to form a cemented lens.

[0128] The optical lens provided by the present application can be used as, for example, an imaging lens, in which case light from an object sequentially passes through the surfaces S1 to S8 and is finally imaged on an imaging surface provided on the second side, wherein an image sensing chip IMA is provided at the imaging surface. It should be understood that the optical lens provided by the present application can also be used as, for example, a projection lens (such as a smart headlamp lens), in which case light from an image source side sequentially passes through the surfaces S8 to S1 and is finally projected onto a projection surface (not shown) provided on the first side, wherein an image sensing chip IMA is provided at the image source surface.

[0129] The optical lens can further include a stop STO, which can be provided between the first lens L1 and the second lens L2 to improve the imaging quality. For example, the stop STO can be provided at a position between the first lens L1 and the second lens L2 close to the second side S2 of the first lens L1.

[0130] Optionally, the optical lens can further include a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further include a protection glass L6 (not shown) having a first side and a second side. The protection glass L6 can be used to protect the image sensor chip IMA located at the second side.

[0131] Table 1 shows the radius of curvature R, thickness / distance d (it should be understood that the thickness / distance d in the row of S1 is the central thickness d1 of the first lens L1, the thickness / distance d in the row of S2 is the interval distance d1s of the first lens L1 and the diaphragm STO on the optical axis, and so on), refractive index Nd, and Abbe number Vd of each lens of the optical lens of Example 1.

[0132]

[0133]

[0134] Table 1

[0135] In Example 1, the object side and image side S1, S2, S6, S7 and S8 of the first lens L1, the third lens L3 and the fourth lens L4 can all be aspherical surfaces, and the surface type x of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0136]

[0137] wherein x is the distance sag from the vertex of the aspherical surface when the aspherical surface is at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the inverse of the radius of curvature R in Table 1 above); k is the conic coefficient; and Ai is the correction coefficient of the i-th order of the aspherical surface. Table 2 below gives the conic coefficient k and high-order term coefficients A4, A6, A8 and A10 that can be used for the aspherical surfaces S6 and S7 in Example 1.

[0138] Face number k A4 A6 A8 A10 S1 -115.4970 1.2514E-03 -2.0258E-05 -9.7893E-07 2.7815E-08 S2 0.6160 1.6874E-03 -1.0434E-05 -1.3156E-06 1.5712E-08 S6 4.2539 -8.7568E-05 1.7637E-06 S7 -123.4744 -2.1385E-05 -1.1331E-07 S8 -0.8773 -4.3104E-05 2.8054E-07

[0139] Table 2

[0140] Example 2

[0141] The optical lens according to Example 2 of the present application is described below. Figure 2 The optical lens according to Example 2 of the present application is described below. Figure 2 A structure schematic diagram of the optical lens according to Example 2 of the present application is shown.

[0142] As Figure 2As shown, the optical lens comprises, in sequence along the optical axis from the first side to the second side, a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4.

[0143] The first lens L1 is a convex-concave lens with negative focal power, the first side S1 of which is convex and the second side S2 of which is concave. The second lens L2 is a biconvex lens with positive focal power, the first side S4 of which is convex and the second side S5 of which is convex. The third lens L3 is a biconcave lens with negative focal power, the first side S6 of which is concave and the second side S7 of which is concave. The fourth lens L4 is a biconvex lens with positive focal power, the first side S7 of which is convex and the second side S8 of which is convex. The third lens L3 and the fourth lens L4 are cemented to form a cemented lens.

[0144] The optical lens provided by the present application can be used as, for example, an imaging lens, in which case light from an object sequentially passes through each of the surfaces S1 to S8 and is finally imaged on an imaging surface provided on the second side, wherein an image sensing chip IMA is provided at the imaging surface. It should be understood that the optical lens provided by the present application can also be used as, for example, a projection lens (such as a smart headlamp lens), in which case light from an image source side sequentially passes through each of the surfaces S8 to S1 and is finally projected onto a projection surface (not shown) provided on the first side, wherein an image sensing chip IMA is provided at the image source surface.

[0145] The optical lens can further comprise a stop STO, which can be provided between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO can be provided between the first lens L1 and the second lens L2 at a position close to the second side S2 of the first lens L1.

[0146] Optionally, the optical lens can further comprise a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further comprise a protective glass L6 (not shown) having a first side and a second side. The protective glass L6 can be used to protect the image sensing chip IMA located at the second side.

[0147] Table 3 shows the radius of curvature R, the thickness / distance d, the refractive index Nd and the Abbe number Vd of each lens of the optical lens of Example 2. Table 4 shows the conic coefficient and the high-order term coefficient that can be used for each aspheric surface in Example 2, wherein each aspheric surface can be defined by the formula (1) given in Example 1 above.

[0148]

[0149] Table 3

[0150] Face number k A4 A6 A8 A10 S1 108.8168 1.2540E-03 -3.0286E-05 -9.7927E-07 2.7778E-08 S2 0.6149 1.6854E-03 -1.0259E-05 -1.3090E-06 1.5374E-08 S6 4.2564 -8.0509E-05 1.7022E-06 S7 -130.4365 -2.3385E-05 -1.8731E-07 S8 -0.8780 -4.3525E-05 8.7098E-07

[0151] Table 4

[0152] Example 3

[0153] The following refers to Figure 3 An optical lens according to Embodiment 3 of the present application is described. Figure 3 A structural schematic diagram of the optical lens according to Embodiment 3 of the present application is shown.

[0154] As Figure 3 shown, the optical lens comprises, in order from the first side to the second side along the optical axis, a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4.

[0155] The first lens L1 is a double-concave lens with negative optical power, the first side S1 of which is concave, and the second side S2 of which is concave. The second lens L2 is a double-convex lens with positive optical power, the first side S4 of which is convex, and the second side S5 of which is convex. The third lens L3 is a double-concave lens with negative optical power, the first side S6 of which is concave, and the second side S7 of which is concave. The fourth lens L4 is a double-convex lens with positive optical power, the first side S7 of which is convex, and the second side S8 of which is convex. The third lens L3 and the fourth lens L4 are cemented to form a cemented lens.

[0156] The optical lens provided by the present application can be used as, for example, an imaging lens, in which case light from an object sequentially passes through each of the surfaces S1 to S8 and is finally imaged on an imaging surface provided on the second side, wherein an image sensing chip IMA is provided at the imaging surface. It should be understood that the optical lens provided by the present application can also be used as, for example, a projection lens (such as a smart headlamp lens), in which case light from an image source side sequentially passes through each of the surfaces S8 to S1 and is finally projected onto a projection surface (not shown) provided on the first side, wherein an image sensing chip IMA is provided at the image source surface.

[0157] The optical lens can further comprise a stop STO, which can be provided between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO can be provided at a position between the first lens L1 and the second lens L2 close to the second side S2 of the first lens L1.

[0158] Optionally, the optical lens can further comprise a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further comprise a protective glass L6 (not shown) having a first side and a second side. The protective glass L6 can be used to protect the image sensing chip IMA located at the second side.

[0159] Table 5 shows the radius of curvature R, thickness / distance d, refractive index Nd, and Abbe number Vd of each lens of the optical lens of Example 3. Table 6 shows the conic coefficient and high-order coefficient of each aspheric mirror surface that can be used in Example 3, wherein the surface shape of each aspheric surface can be defined by formula (1) given in Example 1 above.

[0160]

[0161] Table 5

[0162] Face number k A4 A6 S1 -120.0002 3.0041E-04 -5.5872E-06 S2 3.0765 1.8863E-03 -2.3010E-05 S6 4.2280 -1.0865E-04 1.2537E-06 S7 -149.9999 -2.3385E-05 -1.1731E-07 S8 -0.8695 -5.4220E-05 6.8475E-07

[0163] Table 6

[0164] Example 4

[0165] The following reference Figure 4 An optical lens according to Example 4 of the present application is described. Figure 4 A schematic structural diagram of an optical lens according to Example 4 of the present application is shown.

[0166] like Figure 4 As shown, the optical lens includes a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis.

[0167] The first lens L1 is a biconcave lens with negative optical power, with its first side S1 and second side S2 being concave. The second lens L2 is a biconvex lens with positive optical power, with its first side S4 and second side S5 being convex. The third lens L3 is a biconcave lens with negative optical power, with its first side S6 and second side S7 being concave. The fourth lens L4 is a biconvex lens with positive optical power, with its first side S7 and second side S8 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a cemented lens.

[0168] The optical lens provided in this application can be used as, for example, an imaging lens. In this case, light from an object sequentially passes through each surface S1 to S8 and is ultimately imaged on an imaging surface disposed on the second side, wherein an image sensor chip IMA is disposed on the imaging surface. It should be understood that the optical lens provided in this application can also be used as, for example, a projection lens (such as a smart headlight lens). In this case, light from the image source side sequentially passes through each surface S8 to S1 and is ultimately projected onto a projection surface (not shown) disposed on the first side, wherein an image sensor chip IMA is disposed on the image source surface.

[0169] The optical lens may further include a stop STO, which may be disposed between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO may be disposed between the first lens L1 and the second lens L2 near the second side surface S2 of the first lens L1.

[0170] Optionally, the optical lens can further include a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further include a protection glass L6 (not shown) having a first side and a second side. The protection glass L6 can be used to protect the image sensor chip IMA located at the second side.

[0171] Table 7 shows the radius of curvature R, the thickness / distance d, the refractive index Nd and the Abbe number Vd of each lens of the optical lens of Example 4. Table 8 shows the conic coefficient and the high-order term coefficient of each aspherical surface that can be used in the optical lens of Example 4, wherein each aspherical surface can be defined by the formula (1) given in Example 1 above.

[0172]

[0173] Table 7

[0174]

[0175]

[0176] Table 8

[0177] Example 5

[0178] The optical lens according to Example 5 of the present application is described below with reference to Figure 5 The structure of the optical lens according to Example 5 of the present application is shown in FIG. 5. Figure 5 The structure of the optical lens according to Example 5 of the present application is shown in FIG. 5.

[0179] As shown in FIG. 5, the optical lens includes, in order from the first side to the second side along the optical axis, a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4. Figure 5

[0180] The first lens L1 is a double-concave lens having a negative focal power, the first side S1 of which is a concave surface and the second side S2 of which is a concave surface. The second lens L2 is a double-convex lens having a positive focal power, the first side S4 of which is a convex surface and the second side S5 of which is a convex surface. The third lens L3 is a meniscus lens having a negative focal power, the first side S6 of which is a concave surface and the second side S7 of which is a convex surface. The fourth lens L4 is a double-convex lens having a positive focal power, the first side S8 of which is a convex surface and the second side S9 of which is a convex surface.

[0181] ​The optical lens provided in the present application can be used as, for example, an imaging lens, in which case light from an object sequentially passes through each surface S1 to S9 and is finally imaged on an imaging surface provided on the second side, wherein an image sensor chip IMA is provided at the imaging surface. It should be understood that the optical lens provided in the present application can also be used as, for example, a projection lens (such as a smart headlamp lens), in which case light from an image source side sequentially passes through each surface S9 to S1 and is finally projected onto a projection surface (not shown) provided on the first side, wherein an image sensor chip IMA is provided at the image source surface.

[0182] The optical lens can further include a stop STO, which can be provided between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO can be provided between the first lens L1 and the second lens L2 at a position close to the second side surface S2 of the first lens L1.

[0183] Optionally, the optical lens can further include a filter L5 (not shown) having a first side surface and a second side surface. The filter L5 can be used to correct color deviation. The optical lens can further include a protective glass L6 (not shown) having a first side surface and a second side surface. The protective glass L6 can be used to protect the image sensor chip IMA located at the second side surface.

[0184] Table 9 shows the radius of curvature R, thickness / distance d, refractive index Nd, and Abbe number Vd of each lens of the optical lens of Example 5. Table 10 shows the conic coefficient and high-order term coefficient that can be used for each aspherical surface of Example 5, wherein each aspherical surface can be defined by the formula (1) given in Example 1 above.

[0185]

[0186]

[0187] Table 9

[0188] Face number k A4 A6 S1 -56.0663 5.3131E-05 S2 0.3134 5.6051E-04 S6 4.0833 -8.6655E-05 1.1104E-06 S7 8330.5083 S8 85.6369 -2.3385E-05 -1.1731E-07 S9 -9.16E-01 -2.75E-05 4.55E-07

[0189] Table 10

[0190] Example 6

[0191] The following refers to Figure 6 An optical lens according to Example 6 of the present application is described. Figure 6 A structural schematic diagram of the optical lens according to Example 6 of the present application is shown.

[0192] As Figure 6 shown, the optical lens sequentially includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4 along the optical axis from the first side to the second side.

[0193] The first lens L1 is a double-concave lens with negative focal power, the first side S1 is a concave surface, and the second side S2 is a concave surface. The second lens L2 is a double-convex lens with positive focal power, the first side S4 is a convex surface, and the second side S5 is a convex surface. The third lens L3 is a meniscus lens with negative focal power, the first side S6 is a concave surface, and the second side S7 is a convex surface. The fourth lens L4 is a double-convex lens with positive focal power, the first side S8 is a convex surface, and the second side S9 is a convex surface.

[0194] The optical lens provided by the present application can be used as, for example, an imaging lens, at this time, light from an object sequentially passes through each surface S1 to S9 and is finally imaged on an imaging surface arranged on the second side, wherein an image sensing chip IMA is arranged at the imaging surface. It should be understood that the optical lens provided by the present application can also be used as, for example, a projection lens (such as a smart headlight lens), at this time, light from an image source side sequentially passes through each surface S9 to S1 and is finally projected onto a projection surface (not shown) arranged on the first side, wherein an image sensing chip IMA is arranged at the image source surface.

[0195] The optical lens can further include a stop STO, which can be arranged between the first lens L1 and the second lens L2 to improve the imaging quality. For example, the stop STO can be arranged between the first lens L1 and the second lens L2 at a position close to the second side S2 of the first lens L1.

[0196] Optionally, the optical lens can further include a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further include a protective glass L6 (not shown) having a first side and a second side. The protective glass L6 can be used to protect the image sensing chip IMA located at the second side.

[0197] Table 11 shows the curvature radius R, thickness / distance d, refractive index Nd, and Abbe number Vd of each lens of the optical lens of Example 6. Table 12 shows the conic coefficient and high-order term coefficient that can be used for each aspheric surface in Example 6, wherein each aspheric surface can be defined by the formula (1) given in Example 1 above.

[0198]

[0199] Table 11

[0200] Face number k A4 A6 S1 -73.8563 2.3477E-05 S2 0.0829 5.7820E-04 S6 4.0559 -5.7108E-05 1.3847E-06 S7 10661.7524 S8 120.5976 -2.3385E-05 -1.1731E-07 S9 -0.9170 -4.74E-05 4.82E-07

[0201] Table 12

[0202] Example 7

[0203] The following refers to Figure 7 An optical lens according to Example 7 of the present application is described.Figure 7 A structural schematic of an optical lens according to Embodiment 7 of the present application is shown.

[0204] As shown in Figure 7 the optical lens comprises, in order from the first side to the second side along the optical axis, a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4.

[0205] The first lens L1 is a convex-concave lens with negative refractive power, the first side S1 of which is a convex surface and the second side S2 of which is a concave surface. The second lens L2 is a biconvex lens with positive refractive power, the first side S4 of which is a convex surface and the second side S5 of which is a convex surface. The third lens L3 is a biconcave lens with negative refractive power, the first side S6 of which is a concave surface and the second side S7 of which is a concave surface. The fourth lens L4 is a biconvex lens with positive refractive power, the first side S8 of which is a convex surface and the second side S9 of which is a convex surface.

[0206] The optical lens provided by the present application can be used as, for example, an imaging lens, in which case light from an object sequentially passes through each of the surfaces S1 to S9 and is finally imaged on an imaging surface provided on the second side, wherein an image sensing chip IMA is provided at the imaging surface. It should be understood that the optical lens provided by the present application can also be used as, for example, a projection lens (such as a smart headlamp lens), in which case light from an image source side sequentially passes through each of the surfaces S9 to S1 and is finally projected onto a projection surface (not shown) provided on the first side, wherein an image sensing chip IMA is provided at the image source surface.

[0207] The optical lens can further comprise a stop STO, which can be provided between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO can be provided at a position between the first lens L1 and the second lens L2 close to the second side S2 of the first lens L1.

[0208] Optionally, the optical lens can further comprise a filter L5 (not shown) having a first side and a second side. The filter L5 can be used to correct color deviation. The optical lens can further comprise a protective glass L6 (not shown) having a first side and a second side. The protective glass L6 can be used to protect the image sensing chip IMA located at the second side.

[0209] Table 13 shows the radius of curvature R, the thickness / distance d, the refractive index Nd, and the Abbe number Vd of each lens of the optical lens of Embodiment 7. Table 14 shows the conic coefficient and the high-order term coefficient that can be used for each aspheric surface in Embodiment 7, wherein each aspheric surface can be defined by the formula (1) given in Embodiment 1 above.

[0210]

[0211] Table 13

[0212] Face number k A4 A6 A8 A10 S1 119.9234 1.2616E-03 -2.0950E-05 -1.0079E-06 2.8568E-08 S2 0.6157 1.7894E-03 -1.3923E-05 -1.2747E-06 1.7819E-08 S6 4.2751 -5.2044E-05 1.7488E-06 S7 -166.9759 -2.6321E-05 -7.0514E-08 S8 -150.0030 -5.3885E-05 -1.1031E-07 S9 -8.83E-01 -4.19E-05 7.85E-07

[0213] Table 14

[0214] Example 8

[0215] The following reference Figure 8 An optical lens according to Example 8 of the present application is described. Figure 8 A structural schematic diagram of an optical lens according to Example 8 of the present application is shown.

[0216] like Figure 8 As shown, the optical lens includes a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in sequence from the first side to the second side along the optical axis.

[0217] The first lens L1 is a convex-concave lens with negative optical power, with its first side surface S1 being convex and its second side surface S2 being concave. The second lens L2 is a biconvex lens with positive optical power, with its first side surface S4 being convex and its second side surface S5 being convex. The third lens L3 is a biconcave lens with negative optical power, with its first side surface S6 being concave and its second side surface S7 being concave. The fourth lens L4 is a biconvex lens with positive optical power, with its first side surface S8 being convex and its second side surface S9 being convex.

[0218] The optical lens provided in this application can be used as, for example, an imaging lens. In this case, light from an object sequentially passes through each surface S1 to S9 and is ultimately imaged on an imaging surface disposed on the second side, wherein an image sensor chip IMA is disposed on the imaging surface. It should be understood that the optical lens provided in this application can also be used as, for example, a projection lens (such as a smart headlight lens). In this case, light from the image source side sequentially passes through each surface S9 to S1 and is ultimately projected onto a projection surface (not shown) disposed on the first side, wherein an image sensor chip IMA is disposed on the image source surface.

[0219] The optical lens may further include a stop STO, which may be disposed between the first lens L1 and the second lens L2 to improve imaging quality. For example, the stop STO may be disposed between the first lens L1 and the second lens L2 near the second side surface S2 of the first lens L1.

[0220] Optionally, the optical lens may further include a filter L5 (not shown) having a first side surface and a second side surface. The filter L5 may be used to correct color deviation. The optical lens may further include a protective glass L6 (not shown) having a first side surface and a second side surface. The protective glass L6 may be used to protect the image sensor chip IMA located on the second side surface.

[0221] Table 15 shows the radius of curvature R, thickness / distance d, refractive index Nd, and Abbe number Vd of each lens of the optical lens of Example 8. Table 16 shows the conic coefficient and high-order term coefficient of each aspherical surface that can be used in the aspherical surfaces of Example 8, wherein each aspherical surface can be defined by the formula (1) given in Example 1 above.

[0222]

[0223] Table 15

[0224] Face number k A4 A6 A8 A10 S1 125.1750 1.2618E-03 -2.0982E-05 -1.0091E-06 2.8523E-08 S2 0.6184 1.7089E-03 -1.3838E-05 -1.3693E-06 1.8090E-08 S6 4.2742 -4.1833E-05 1.7491E-06 S7 -165.2807 -2.6376E-05 -7.1449E-08 S8 -149.6285 -2.3311E-05 -4.3640E-07 S9 -8.84E-01 -4.18E-05 7.84E-07

[0225] Table 16

[0226] In summary, Examples 1 to 8 respectively satisfy the relationships shown in Table 17-1 and Table 17-2 below. In Table 17-1 and Table 17-2, the units of TTL, F, TL, BFL, D, H, R1, R2, R4, R5, d1, d2, d4, D3, D4, F1, F2, F3, F4, F34 are millimeters (mm), and the unit of FOV is degree (°).

[0227]

[0228]

[0229] Table 17-1

[0230]

[0231]

[0232] Table 17-2

[0233] The present application also provides an electronic device, which can include the optical lens according to the above embodiments 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 can be a standalone electronic device such as a distance detection camera, or an imaging module integrated on a distance detection device such as an auxiliary driving system. In addition, the electronic device can also be a standalone imaging device such as a vehicle-mounted camera, or an imaging module integrated on an auxiliary driving system.

[0234] The above description is merely preferred embodiments of the present application and a description of the principles of the technology used. It should be understood by those skilled in the art that the scope of the application involved in the present application is not limited to the technical solutions formed by the specific combinations of the above technical features, and also covers other technical solutions formed by any combination of the above technical features or equivalent features without departing from the inventive concept. For example, the above features are replaced with each other to form technical solutions with similar functions disclosed in the present application (but not limited to).

Claims

1. An optical lens, characterized in that: The optical lens includes, in order from the first side to the second side along the optical axis: a first lens having negative optical power, wherein the second side surface thereof is concave; a second lens having positive optical power, wherein the first side surface is convex and the second side surface is convex; a third lens element having negative optical power, wherein the first side surface of the third lens element is concave; and a fourth lens element having positive optical power, wherein the first side surface is convex and the second side surface is convex; The number of lenses having optical power in the optical lens is four; A distance TL from the first side surface of the first lens to the second side surface of the fourth lens on the optical axis and a center thickness d4 of the fourth lens on the optical axis satisfy the following conditions: 3.504≤TL / d4≤5; The total length TTL of the optical lens and the total effective focal length F of the optical lens satisfy the following conditions: 3.260≤TTL / F≤5; A center thickness d1 of the first lens on the optical axis and a center thickness d2 of the second lens on the optical axis satisfy the following: 4≤d2 / d1≤6.

533.

2. The optical lens according to claim 1, wherein: The first side surface of the first lens is a convex surface or a concave surface.

3. The optical lens according to claim 1, wherein: The second side surface of the third lens is a concave surface or a convex surface.

4. The optical lens according to claim 1, wherein: The third lens and the fourth lens are cemented together to form a cemented lens.

5. The optical lens according to any one of claims 1 to 4, characterized in that: The total length TTL 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 satisfy the following conditions: TTL / H / FOV≤0.

35.

6. The optical lens according to any one of claims 1 to 4, characterized in that: The total effective focal length F of the optical lens and the maximum light clearance D of the first side surface of the first lens corresponding to the maximum field angle of the optical lens satisfy the following: 0.2≤F / D≤2.

7. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum field of view FOV of the optical lens, the maximum clear aperture D of the first side surface of the first lens corresponding to the maximum field of view of the optical lens, and the image height H corresponding to the maximum field of view of the optical lens satisfy the following conditions: D / H / FOV≤0.

05.

8. The optical lens according to any one of claims 1 to 4, characterized in that: A back focal length BFL of the optical lens and a total length TTL of the optical lens satisfy the following: 0.35≤BFL / TTL≤0.

495.

9. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum half field of view HFOV of the optical lens and the total effective focal length F of the optical lens satisfy the following conditions: 2 mm ≤ F×TAN(HFOV) ≤ 5.245 mm.

10. The optical lens according to any one of claims 1 to 4, characterized in that: The total effective focal length F of the optical lens and the central curvature radius R1 of the first side surface of the first lens satisfy: 1≤|R1 / F|≤19.

020.

11. The optical lens according to any one of claims 1 to 4, characterized in that: The total effective focal length F of the optical lens and the central curvature radius R4 of the first side surface of the second lens satisfy: 1.5≤R4 / F≤4.

908.

12. The optical lens according to any one of claims 1 to 4, characterized in that: The total effective focal length F of the optical lens, the central curvature radius R4 of the first side surface of the second lens, and the central curvature radius R5 of the second side surface of the second lens satisfy: 1.194≤|F / R4|+|F / R5|≤5.

13. The optical lens according to any one of claims 1 to 4, characterized in that: A central curvature radius R2 of the second side surface of the first lens and a central curvature radius R4 of the first side surface of the second lens satisfy: -1≤(R2-R4) / (R2+R4)≤-0.

2.

14. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F1 of the first lens and the effective focal length F2 of the second lens satisfy the following: 0.935≤|F2 / F1|≤4.

15. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F1 of the first lens and the effective focal length F3 of the third lens satisfy the following: 0.374≤F1 / F3≤2.

16. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F3 of the third lens and the total effective focal length F of the optical lens satisfy the following: 1≤|F3 / F|≤5.

17. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy the following: 1.382≤F4 / F≤5.

18. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F3 of the third lens and the effective focal length F4 of the fourth lens satisfy the following: 1≤|F3 / F4|≤2.

19. The optical lens according to any one of claims 1 to 4, characterized in that: The combined focal length F34 of the third lens and the fourth lens and the total effective focal length F of the optical lens satisfy the following: 2.653≤F34 / F≤6.

20. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum clear aperture D4 of the first side surface of the fourth lens corresponding to the maximum field of view of the optical lens and the distance TL from the first side surface of the first lens to the second side surface of the fourth lens on the optical axis satisfy the following conditions: 0.5≤D4 / TL≤0.

835.

21. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum light-clearance diameter D4 of the first side surface of the fourth lens corresponding to the maximum field angle of the optical lens and the total length TTL of the optical lens satisfy the following: 0.25≤D4 / TTL≤0.

430.

22. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum clear aperture D3 of the first side surface of the third lens corresponding to the maximum field of view of the optical lens and the distance TL from the first side surface of the first lens to the second side surface of the fourth lens on the optical axis satisfy the following conditions: 0.5≤D3 / TL≤0.

775.

23. The optical lens according to any one of claims 1 to 4, characterized in that: The maximum light-clearance D3 of the first side surface of the third lens corresponding to the maximum field angle of the optical lens and the total length TTL of the optical lens satisfy the following: 0.25≤D3 / TTL≤0.

406.

24. The optical lens according to any one of claims 1 to 4, characterized in that: The Abbe number Vd3 of the third lens and the Abbe number Vd4 of the fourth lens satisfy the following: 1.6≤Vd4 / Vd3≤2.

380.

25. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy the following: 0.980≤|F1 / F|≤7.

26. The optical lens according to any one of claims 1 to 4, characterized in that: The effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy the following: 1.071≤|F2 / F|≤7.

27. An electronic device, characterized in that: The invention comprises an optical lens according to any one of claims 1 to 26 and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

Images