Optical lens

Abstract

The application discloses an optical lens. The optical lens comprises, in sequence from an object side to an image side along an optical axis, a first lens with negative refractive power, an object side surface of which is a convex surface and an image side surface of which is a concave surface; a second lens with refractive power, an object side surface of which is a concave surface; a third lens with positive refractive power, an object side surface of which is a convex surface and an image side surface of which is a convex surface; a fourth lens with positive refractive power, an object side surface of which is a convex surface and an image side surface of which is a convex surface; a fifth lens with negative refractive power, an image side surface of which is a concave surface; and a sixth lens with positive refractive power, an object side surface of which is a convex surface and an image side surface of which is a convex surface; a distance BFL between the image side surface of the sixth lens and an imaging surface of the optical lens on the optical axis and a distance TL between the object side surface of the first lens and the image side surface of the sixth lens on the optical axis satisfy 2.2 <= BFL / TL <= 3.3.

Description

Technical Field

[0001] This application relates to the field of optical components, and more specifically, to an optical lens. Background Technology

[0002] With the increasing awareness of security, video doorbells have developed and become widespread, and are now commonly used in various private and public places. Fixed-focus wide-angle lenses, due to their advantages such as wide field of view and clear imaging, are widely used in doorbells and other security products.

[0003] Doorbell systems are mostly exposed to outdoor environments, so the lens needs to ensure clear imaging in different temperature conditions. Additionally, because the image captured by the lens is insufficiently bright at night or in low-light conditions, resulting in unclear images, doorbell lenses typically use infrared illumination to achieve this imaging purpose.

[0004] However, wide-angle lenses on the market still have many problems. For example: 1) Wide-angle lenses on the market are often large in size and length, which cannot meet the requirements of miniaturization; 2) Lenses on the market that can meet the requirements of small size and large field of view often have small apertures, which cannot adapt to dark environments such as night or rainy days; 3) Wide-angle lenses with all-glass structures on the market are often heavy, which cannot meet the requirements of lightweighting, and the cost is also high.

[0005] Therefore, the market urgently needs wide-angle lenses that can achieve small size, large aperture, and day and night focus. Utility Model Content

[0006] This application provides an optical lens comprising, along the optical axis from the object side to the image side, the following components in sequence: a first lens with negative optical power, having a convex object side and a concave image side; a second lens with optical power, having a concave object side; a third lens with positive optical power, having a convex object side and a convex image side; a fourth lens with positive optical power, having a convex object side and a convex image side; a fifth lens with negative optical power, having a concave image side; and a sixth lens with positive optical power, having a convex object side and a convex image side; wherein the distance BFL from the image side of the sixth lens to the imaging plane of the optical lens on the optical axis and the distance TL from the object side of the first lens to the image side of the sixth lens on the optical axis satisfy: 2.2 ≤ BFL / TL ≤ 3.3.

[0007] In one embodiment, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.65≤f1 / f≤-1.25.

[0008] In one embodiment, the radius of curvature r2 of the image-side surface of the first lens and the effective focal length f1 of the first lens satisfy: -0.5≤r2 / f1≤-0.2.

[0009] In one embodiment, the effective focal length f3 of the third lens and the effective focal length f2 of the second lens satisfy: -0.60≤f3 / f2≤0.35.

[0010] In one embodiment, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.5≤f3 / f≤4.5.

[0011] In one embodiment, the refractive index nd2 of the second lens satisfies: 1.5≤nd2≤1.7; the refractive index nd3 of the third lens satisfies: 1.5≤nd3≤1.7; the Abbe number vd2 of the second lens satisfies: 20≤vd2≤60; and the Abbe number vd3 of the third lens satisfies: 20≤vd3≤60.

[0012] In one embodiment, the center thickness CT3 of the third lens on the optical axis and the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfy: 0.03≤CT3 / TTL≤0.15.

[0013] In one embodiment, the combined focal length fa of the first lens and the second lens satisfies the condition that -3.0 ≤ fa / f ≤ -0.5 with respect to the effective focal length f of the optical lens.

[0014] In one embodiment, the combined focal length fb of the third, fourth, fifth, and sixth lenses satisfies the condition that 1.2 ≤ fb / f ≤ 1.9 with respect to the effective focal length f of the optical lens.

[0015] In one embodiment, the effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.4≤f4 / f≤2.7.

[0016] In one embodiment, the effective focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.2≤f5 / f≤-1.2.

[0017] In one embodiment, the effective focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: 1.3≤f6 / f≤2.1.

[0018] In one embodiment, the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfies the following condition: 5.3≤TTL / f≤5.9.

[0019] In one embodiment, the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfies the following condition: 7≤TTL / FNO≤8.

[0020] In one embodiment, the air gap T45 between the fourth and fifth lenses on the optical axis and the distance TTL between the object side of the first lens and the imaging surface of the optical lens on the optical axis satisfy: 0.15≤100×T45 / TTL≤3.30.

[0021] In another aspect, this application provides an electronic device. This electronic device includes an optical lens according to this application and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

[0022] This application provides a six-element wide-angle lens. By optimizing the shape of each lens, the optical power, and the reasonable setting of related parameters, the optical lens has at least one beneficial effect, such as small size (TTL≤13mm), large aperture (FNO≤1.6), day and night confocal focus, and the ability to achieve no blurring during high and low temperature processes. Attached Figure Description

[0023] Other features, objects, and advantages of this utility application will become more apparent from the following detailed description of the embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0024] Figure 1 This is a schematic diagram illustrating the structure of an optical lens according to Embodiment 1 of this application;

[0025] Figure 2 To illustrate the structure of the optical lens according to Embodiment 2 of this application;

[0026] Figure 3 To illustrate the structure of the optical lens according to Embodiment 3 of this application;

[0027] Figure 4 To illustrate the structural schematic diagram of the optical lens according to Embodiment 4 of this application; and

[0028] Figure 5 This is a schematic diagram illustrating the structure of an optical lens according to Embodiment 5 of this application. Detailed Implementation

[0029] To facilitate understanding of this application, a more complete description of the application will be provided below with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of the application and are not intended to limit the scope of the application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0030] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0031] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0032] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging side is called the image-side surface of the lens.

[0033] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0034] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] The features, principles and other aspects of this application are described in detail below.

[0037] In an exemplary embodiment, the optical lens includes, for example, six lenses with optical power, namely a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. These six lenses are arranged sequentially along the optical axis from the object side to the image side, and any two adjacent lenses among the first to sixth lenses may have a gap distance between them.

[0038] In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the image side of the sixth lens. Optionally, the photosensitive element disposed on the image side of the sixth lens may be a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS).

[0039] In an exemplary embodiment, an aperture stop may be provided between the second and third lenses to limit the light beam and further improve the imaging quality of the optical lens. The aperture stop helps to concentrate the light entering the optical lens, reduce the maximum aperture of the optical lens, and decrease the assembly sensitivity of the system. In other embodiments of this application, the aperture stop may also be provided between the third and fourth lenses. However, it should be noted that the positions of the aperture stops disclosed herein are merely examples and not limitations; in alternative embodiments, the aperture stop may be placed in other positions as needed.

[0040] In an exemplary embodiment, the first lens has negative optical power, with its object-side surface being convex and its image-side surface being concave. The negative optical power and convex-concave shape of the first lens help increase the amount of light entering the system, thereby achieving a large field of view and a large aperture. Simultaneously, the smaller radius of curvature of the image-side surface of the first lens helps the system maintain a small aperture while achieving a large field of view, thus meeting miniaturization design requirements.

[0041] In an exemplary embodiment, the second lens has positive or negative optical power, with its object-side surface being concave and its image-side surface being convex or concave. The object-side surface of the second lens is concave towards the object side, which helps to deflect light and alleviate the light-gathering pressure of the first lens, thereby meeting the requirements of a large field of view and a large aperture. The second lens is a relatively thick meniscus lens, which is beneficial for correcting aberrations such as field curvature of the system, thereby ensuring clear resolution of the system.

[0042] In an exemplary embodiment, the third lens has positive optical power, and its object-side surface is convex, as is its image-side surface. The third lens, having positive optical power and a biconvex shape, can share the positive optical power of the fourth and sixth lenses, preventing the core thickness (i.e., center thickness) of the fourth and sixth lenses from becoming excessive. This ensures lens manufacturability and also helps reduce costs.

[0043] In an exemplary embodiment, the fourth lens has positive optical power, and both its object-side and image-side surfaces are convex. The positive optical power and biconvex shape of the fourth lens facilitate the correction of system chromatic aberration, thereby meeting higher imaging requirements.

[0044] In an exemplary embodiment, the fifth lens has negative optical power, and its object-side surface is convex or concave, while its image-side surface is concave. The negative optical power and concave image-side surface of the fifth lens help to elevate light rays and increase the image height. Furthermore, by setting the object-side surface of the fifth lens to an aspherical shape, field curvature and astigmatism of the system can be effectively corrected, thereby improving the system's resolution. The relatively curved image-side surface of the fifth lens helps to reduce related ghosting.

[0045] In an exemplary embodiment, the sixth lens has positive optical power, with both its object-side and image-side surfaces being convex. The sixth lens's positive optical power and biconvex shape facilitate a smaller principal ray incident angle, while further correcting chromatic aberration and distortion to improve image quality.

[0046] In an exemplary embodiment, the optical lens according to this application satisfies: 2.2 ≤ BFL / TL ≤ 3.3, where BFL is the distance on the optical axis from the image-side surface of the sixth lens to the imaging surface of the optical lens, and TL is the distance on the optical axis from the object-side surface of the first lens to the image-side surface of the sixth lens. Satisfying 2.2 ≤ BFL / TL ≤ 3.3 can meet the special requirements of the back focal length of the optical lens, and also helps to reserve space for the installation and focusing of optical components, avoiding interference when assembling the optical lens and optical components.

[0047] In an exemplary embodiment, the optical lens according to this application satisfies: -1.65 ≤ f1 / f ≤ -1.25, where f1 is the effective focal length of the first lens and f is the effective focal length of the optical lens. Satisfying -1.65 ≤ f1 / f ≤ -1.25 gives the first lens an appropriate negative optical power, which is beneficial for bringing more light into the system to meet the requirement of a large field of view.

[0048] In an exemplary embodiment, the optical lens according to this application satisfies: -0.5 ≤ r2 / f1 ≤ -0.2, where r2 is the radius of curvature of the image-side surface of the first lens, and f1 is the effective focal length of the first lens. Satisfying -0.5 ≤ r2 / f1 ≤ -0.2 ensures that the image-side surface of the first lens has an appropriate radius of curvature, which helps to reduce its structural aperture while ensuring the lens can be manufactured, ultimately resulting in a smaller lens diameter and miniaturization.

[0049] In an exemplary embodiment, the optical lens according to this application satisfies: -0.60≤f3 / f2≤0.35, where f3 is the effective focal length of the third lens and f2 is the effective focal length of the second lens. Satisfying -0.60≤f3 / f2≤0.35, by rationally allocating the focal lengths of the second and third lenses, allows the light entering the system to transition smoothly and converge at an appropriate angle, reducing the pressure on aberration correction of the rear lens elements; it also facilitates the appropriate lifting of light to increase the system aperture; and it further facilitates the rational distribution of the overall refractive power of the optical lens, allowing light to be transmitted smoothly, ultimately improving the imaging resolution of the optical system.

[0050] In an exemplary embodiment, the optical lens according to this application satisfies: 2.5 ≤ f3 / f ≤ 4.5, where f3 is the effective focal length of the third lens and f is the effective focal length of the optical lens. Satisfying 2.5 ≤ f3 / f ≤ 4.5, the focal length of the third lens is reasonably allocated, which is beneficial for sharing the focal length values ​​of the fourth and sixth lenses and for maintaining the performance stability of the third lens.

[0051] In an exemplary embodiment, the refractive index nd2 of the second lens of the optical lens according to this application satisfies: 1.5 ≤ nd2 ≤ 1.7, the refractive index nd3 of the third lens satisfies: 1.5 ≤ nd3 ≤ 1.7, the Abbe number vd2 of the second lens satisfies: 20 ≤ vd2 ≤ 60, and the Abbe number vd3 of the third lens satisfies: 20 ≤ vd3 ≤ 60. By appropriately matching the refractive indices and Abbe numbers of the second and third lenses, and by appropriately selecting the lens materials, the introduction of chromatic aberration can be reduced, and the resolving power of the optical system can be improved.

[0052] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 0.03 ≤ CT3 / TTL ≤ 0.15, where CT3 is the center thickness of the third lens on the optical axis, and TTL is the distance on the optical axis from the object side of the first lens to the imaging surface of the optical lens. By satisfying 0.03 ≤ CT3 / TTL ≤ 0.15, the center thickness of the third lens is reasonably controlled, ensuring that its core thickness (i.e., center thickness) is not excessive, thereby guaranteeing the stability of lens performance and the manufacturability of the lens.

[0053] In an exemplary embodiment, the optical lens according to this application satisfies: -3.0 ≤ fa / f ≤ -0.5, where fa is the combined focal length of the first lens and the second lens, and f is the effective focal length of the optical lens. Satisfying -3.0 ≤ fa / f ≤ -0.5, and reasonably matching the focal length values ​​of the front group (the first lens and the second lens), helps to smoothly converge the front light rays to near the optical axis, which has a good effect on large-angle distortion correction. At the same time, it can effectively constrain off-axis wide beam aberrations, which plays a positive role in improving edge image quality. After the light passes through the aperture, it can smoothly diffuse, which helps to correct the field curvature generated by the lens group located in front of the aperture, reduce the impact of field curvature on resolving power, and improve the quality of the optical system.

[0054] In an exemplary embodiment, the optical lens according to this application satisfies: 1.2 ≤ fb / f ≤ 1.9, where fb is the combined focal length of the third, fourth, fifth, and sixth lenses, and f is the effective focal length of the optical lens. Satisfying 1.2 ≤ fb / f ≤ 1.9, and reasonably matching the focal length values ​​of the rear group (third, fourth, fifth, and sixth lenses), helps to smoothly converge the front light rays to near the optical axis, resulting in better correction of large-angle distortion. Simultaneously, it effectively constrains off-axis wide beam aberrations, positively contributing to the improvement of edge image quality. Furthermore, the light rays can smoothly diffuse after passing through the aperture stop, which helps to correct the field curvature generated by the lens group located in front of the aperture stop, reducing the impact of field curvature on resolving power and improving the quality of the optical system.

[0055] In an exemplary embodiment, the optical lens according to this application satisfies: 1.4 ≤ f4 / f ≤ 2.7, where f4 is the effective focal length of the fourth lens and f is the effective focal length of the optical lens. Satisfying 1.4 ≤ f4 / f ≤ 2.7 ensures that the fourth lens has appropriate positive optical power, which is beneficial for correcting chromatic aberration in the optical system and improving the system's resolving power. Furthermore, a reasonable allocation of optical power also facilitates the control of lens overheating.

[0056] In an exemplary embodiment, the optical lens according to this application satisfies: -2.2 ≤ f5 / f ≤ -1.2, where f5 is the effective focal length of the fifth lens and f is the effective focal length of the optical lens. By satisfying -2.2 ≤ f5 / f ≤ -1.2 and rationally allocating the optical power of the fifth lens, combined with a sixth lens of positive optical power, aberrations such as chromatic aberration, field curvature, and astigmatism generated by the system can be effectively counteracted. This allows the fixed-focus optical system to achieve good imaging quality across the entire field of view, while also contributing to the heat-free operation of the optical system, enabling the lens to achieve good imaging under both high and low temperature conditions.

[0057] In an exemplary embodiment, the optical lens according to this application satisfies: 1.3 ≤ f6 / f ≤ 2.1, where f6 is the effective focal length of the sixth lens and f is the effective focal length of the optical lens. By satisfying 1.3 ≤ f6 / f ≤ 2.1 and rationally allocating the optical power of the sixth lens in conjunction with the negative optical power of the fifth lens, aberrations such as chromatic aberration, field curvature, and astigmatism generated by the system can be effectively counteracted. This allows the fixed-focus optical system to achieve good imaging quality across the entire field of view, while also contributing to the calorific value of the optical system, enabling the lens to achieve good imaging even at high and low temperatures.

[0058] In an exemplary embodiment, the optical lens according to this application satisfies: 5.3 ≤ TTL / f ≤ 5.9, where TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging surface of the optical lens, and f is the effective focal length of the optical lens. Satisfying 5.3 ≤ TTL / f ≤ 5.9 helps to shorten the overall length of the lens, achieving miniaturization. It also avoids problems such as poor overall lens performance due to excessively short overall length, improving the lens's compatibility.

[0059] In an exemplary embodiment, the optical lens according to this application satisfies: 7≤TTL / FNO≤8, where TTL is the distance on the optical axis from the object side of the first lens to the imaging plane of the optical lens, and FNO is the aperture number of the optical lens. Satisfying 7≤TTL / FNO≤8 is beneficial for shortening the overall length of the lens, achieving miniaturization, and avoiding problems such as poor overall lens performance due to excessively small overall length, thereby improving the lens's compatibility.

[0060] In an exemplary embodiment, the optical lens according to this application satisfies: 0.15 ≤ 100 × T45 / TTL ≤ 3.30, where T45 is the air gap between the fourth and fifth lenses on the optical axis, and TTL is the distance on the optical axis from the object side of the first lens to the imaging surface of the optical lens. Satisfying 0.15 ≤ 100 × T45 / TTL ≤ 3.30, by controlling the air gap between the fourth and fifth lenses and changing the relative position of the fourth lens, a more uniform air gap can be maintained between the fourth and fifth lenses. This reduces the impact of gap tolerance on overall performance and is beneficial for correcting system chromatic aberration and improving imaging resolution.

[0061] In an exemplary embodiment, the optical lens of this application has the characteristics of small volume and short total length. The distance TTL between the object side of the first lens and the imaging surface of the optical lens on the optical axis satisfies: TTL≤13mm, so that the optical lens has a small total length and meets the miniaturization feature.

[0062] In an exemplary embodiment, the optical lens of this application has the characteristic of a large field of view, with a maximum field of view of up to 164°. The large field of view allows the lens to be compatible with more application scenarios, thereby enabling it to acquire more scene information to meet the needs of different customers.

[0063] In an exemplary embodiment, the optical lens of this application has the characteristic of a large aperture, which can achieve FNO≤1.60, enabling the optical system to have a larger amount of light transmission, thereby achieving better imaging effect, and clear imaging can be achieved even in environments with relatively insufficient light conditions.

[0064] In an exemplary embodiment, the optical lens of this application can achieve day and night co-focus, is designed to ensure imaging performance in the infrared band, and, in conjunction with the use of an infrared fill light, enables the lens to be suitable for nighttime scenes.

[0065] In an exemplary embodiment, the optical lens of this application uses a combination of different materials for each lens to enable the optical system to present a high-definition image quality lens within a temperature range of -40℃ to 70℃, and to achieve non-defocusing during high and low temperature processes.

[0066] In an exemplary embodiment, the optical lens of this application may, as needed, include a filter and / or protective glass disposed between the sixth lens and the imaging surface to filter light of different wavelengths and prevent damage to the image-side elements (e.g., chips) of the optical lens.

[0067] In an exemplary embodiment, the first to sixth lenses can be spherical lenses or aspherical lenses. This application does not specifically limit the number of spherical and aspherical lenses; when image quality is a primary concern, the number of aspherical lenses can be increased, and even all lenses can be aspherical. Aspherical lenses are characterized by a continuously changing curvature from the lens center to the periphery. Unlike spherical lenses, which have a constant curvature from the lens center to the periphery, aspherical lenses have better radius of curvature characteristics, offering advantages in improving distortion and astigmatism. Using aspherical lenses can minimize aberrations that occur during imaging, thereby improving the lens's image quality. Optionally, the object-side and image-side surfaces of the first to third, fifth, and sixth lenses are aspherical, while the object-side and image-side surfaces of the fourth lens are spherical.

[0068] However, those skilled in the art will understand that the number of lenses constituting the lens can be changed to obtain the various results and advantages described in this specification without departing from the technical solutions claimed in this application. For example, although six lenses are described as an example in the embodiments, the optical lens is not limited to including six lenses. If desired, the optical lens may 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.

[0069] Example 1

[0070] The following is for reference Figure 1 An optical lens according to Embodiment 1 of this application is described. Figure 1 A schematic diagram of the structure of an optical lens according to Embodiment 1 of this application is shown.

[0071] like Figure 1 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6 along the optical axis.

[0072] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0073] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0074] The third lens L3 has positive optical power, and its object side S6 is convex, while its image side S7 is convex.

[0075] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0076] The fifth lens L5 has negative optical power, with its object side S10 being convex and its image side S11 being concave.

[0077] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0078] The optical lens may also include an aperture stop STO, which may be positioned between the second lens L2 and the third lens L3 to improve image quality.

[0079] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0080] Table 1-1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 1, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0081]

[0082] Table 1-1

[0083] In Example 1, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, and sixth lenses are aspherical. The surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0084]

[0085] Where x is the distance vector from the vertex of the aspherical surface at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 1-2 gives the higher-order coefficients A4, A6, A8, A1, A2, A3, A4, A5, A6, A8, A1, A1, A2, A3, A4, A5, A6, A1, A2, A3, A4, A5, A6, A7, A8, A9, A1 ... 10 and A 12 .

[0086] Face number k A4 A6 A8 A10 A12 S1 -2.91 -3.62E-03 8.13E-05 3.48E-06 0.00E+00 0.00E+00 S2 -0.82 4.77E-03 2.36E-02 -1.69E-02 6.58E-03 -9.78E-04 S3 -0.42 -1.78E-03 -3.66E-03 1.46E-03 -8.92E-04 2.23E-04 S4 1.97 -9.87E-03 6.62E-03 -1.04E-03 -6.32E-05 8.34E-05 S6 -44.84 -5.40E-03 -2.85E-04 -4.08E-05 7.50E-05 0.00E+00 S7 9.17 -1.65E-02 2.10E-03 -4.37E-04 1.89E-05 1.32E-05 S10 -32.17 -4.10E-02 4.48E-03 4.46E-05 -6.35E-05 5.27E-06 S11 -5.98 -1.39E-02 3.64E-03 -2.37E-04 -3.79E-05 3.83E-06 S12 -15.58 7.45E-03 1.37E-04 -1.15E-04 7.00E-06 0.00E+00 S13 0.63 3.11E-04 7.21E-04 3.99E-06 7.32E-06 0.00E+00

[0087] Table 1-2

[0088] Example 2

[0089] The following is for reference Figure 2 An optical lens according to Embodiment 2 of this application is described. In this embodiment and the following embodiments, for the sake of brevity, descriptions similar to those in Embodiment 1 will be omitted. Figure 2 A schematic diagram of the structure of an optical lens according to Embodiment 2 of this application is shown.

[0090] like Figure 2 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6 along the optical axis.

[0091] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0092] The second lens L2 has positive optical power, with its object side S3 being concave and its image side S4 being convex.

[0093] The third lens L3 has positive optical power, and its object side S6 is convex, while its image side S7 is convex.

[0094] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0095] The fifth lens L5 has negative optical power, with its object side S10 being convex and its image side S11 being concave.

[0096] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0097] The optical lens may also include an aperture stop STO, which may be positioned between the second lens L2 and the third lens L3 to improve image quality.

[0098] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0099] Table 2-1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 2, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0100]

[0101] Table 2-1

[0102] In Example 2, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, and sixth lenses are aspherical. Table 2-2 shows the higher-order coefficients that can be used for each aspherical mirror surface in Example 2, wherein each conventional aspherical surface type can be defined by formula (1) given in Example 1 above.

[0103] Face number k A4 A6 A8 A10 A12 S1 -5.80 -3.77E-03 1.24E-04 2.27E-06 0.00E+00 0.00E+00 S2 -0.99 2.07E-02 2.74E-03 -1.61E-03 1.16E-03 -2.62E-04 S3 -0.33 -6.47E-04 -4.26E-04 -8.33E-04 5.68E-04 -6.06E-05 S4 -0.01 1.35E-02 -5.47E-03 3.32E-03 -7.21E-04 7.82E-05 S6 7.23 3.56E-03 -1.68E-03 -1.35E-04 3.81E-04 -4.70E-05 S7 2.32 -9.84E-03 1.79E-03 -4.06E-04 3.94E-05 2.61E-05 S10 -84.49 -4.78E-02 5.78E-03 -6.73E-06 -6.05E-05 5.12E-06 S11 -6.52 -1.63E-02 3.06E-03 -9.31E-05 -5.48E-05 4.95E-06 S12 -14.45 3.48E-03 2.64E-06 -9.15E-06 -2.75E-06 0.00E+00 S13 -0.99 9.28E-04 4.50E-04 1.02E-04 -1.09E-06 0.00E+00

[0104] Table 2-2

[0105] Example 3

[0106] The following is for reference Figure 3 An optical lens according to Embodiment 3 of this application is described. Figure 3 A schematic diagram of the structure of an optical lens according to Embodiment 3 of this application is shown.

[0107] like Figure 3 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6 along the optical axis.

[0108] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0109] The second lens L2 has positive optical power, with its object side S3 being concave and its image side S4 being convex.

[0110] The third lens L3 has positive optical power, and its object side S6 is convex, while its image side S7 is convex.

[0111] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0112] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0113] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0114] The optical lens may also include an aperture stop STO, which may be positioned between the second lens L2 and the third lens L3 to improve image quality.

[0115] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0116] Table 3-1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 3, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0117]

[0118] Table 3-1

[0119] In Example 3, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, and sixth lenses are aspherical. Table 3-2 shows the higher-order coefficients that can be used for each aspherical mirror surface in Example 3, wherein each conventional aspherical surface type can be defined by formula (1) given in Example 1 above.

[0120] Face number k A4 A6 A8 A10 A12 S1 -10.50 -2.02E-03 1.28E-04 -1.29E-06 0.00E+00 0.00E+00 S2 -1.04 2.01E-02 9.03E-04 7.89E-04 -5.93E-05 1.10E-05 S3 -0.47 -5.14E-03 -5.67E-04 1.40E-04 3.14E-04 -5.71E-05 S4 0.70 5.58E-03 9.40E-04 5.20E-04 -7.16E-07 0.00E+00 S6 -0.99 -3.30E-03 3.63E-05 8.04E-06 1.17E-04 0.00E+00 S7 1.61 -8.91E-03 8.01E-04 -3.42E-04 1.33E-04 1.41E-05 S10 14.21 -1.92E-02 9.95E-04 1.29E-04 -1.54E-05 7.25E-06 S11 -12.91 -5.32E-03 3.19E-04 6.19E-05 5.86E-06 0.00E+00 S12 -12.32 -1.91E-03 -4.92E-04 2.66E-05 8.95E-06 0.00E+00 S13 -0.85 -1.43E-03 2.61E-04 -1.71E-05 0.00E+00 0.00E+00

[0121] Table 3-2

[0122] Example 4

[0123] The following is for reference Figure 4 An optical lens according to Embodiment 4 of this application is described. Figure 4 A schematic diagram of the structure of an optical lens according to Embodiment 4 of this application is shown.

[0124] like Figure 4 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6 along the optical axis.

[0125] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0126] The second lens L2 has positive optical power, with its object side S3 being concave and its image side S4 being convex.

[0127] The third lens L3 has positive optical power, and its object side S6 is convex, while its image side S7 is convex.

[0128] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0129] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0130] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0131] The optical lens may also include an aperture stop STO, which may be positioned between the second lens L2 and the third lens L3 to improve image quality.

[0132] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0133] Table 4-1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 4, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0134]

[0135] Table 4-1

[0136] In Example 4, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, and sixth lenses are aspherical. Table 4-2 shows the higher-order coefficients that can be used for each aspherical mirror in Example 4, wherein each conventional aspherical surface type can be defined by formula (1) given in Example 1 above.

[0137] Face number k A4 A6 A8 A10 A12 S1 -6.69 -1.69E-03 -9.44E-06 5.18E-06 0.00E+00 0.00E+00 S2 -0.95 1.95E-02 3.41E-04 1.35E-03 -1.63E-04 0.00E+00 S3 -0.42 -5.81E-03 -9.18E-04 3.81E-04 6.45E-05 0.00E+00 S4 0.93 3.03E-03 1.83E-03 3.43E-04 1.35E-05 0.00E+00 S6 -2.69 -4.17E-03 1.18E-03 2.79E-04 7.50E-05 0.00E+00 S7 -13.20 -7.70E-03 9.42E-04 -3.88E-04 2.57E-04 0.00E+00 S10 10.67 -1.67E-02 6.92E-04 1.58E-04 -2.11E-05 3.58E-06 S11 -11.83 -4.68E-03 3.05E-04 5.72E-05 0.00E+00 0.00E+00 S12 -12.92 -1.29E-03 -4.53E-04 6.45E-05 0.00E+00 0.00E+00 S13 -1.87 -7.12E-04 2.04E-04 5.86E-06 0.00E+00 0.00E+00

[0138] Table 4-2

[0139] Example 5

[0140] The following is for reference Figure 5 An optical lens according to Embodiment 5 of this application is described. Figure 5 A schematic diagram of the structure of an optical lens according to Embodiment 5 of this application is shown.

[0141] like Figure 5 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6 along the optical axis.

[0142] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0143] The second lens L2 has negative optical power, and its object side S3 is concave, as is its image side S4.

[0144] The third lens L3 has positive optical power, and its object side S5 is convex, while its image side S6 is convex.

[0145] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0146] The fifth lens L5 has negative optical power, with its object side S10 being convex and its image side S11 being concave.

[0147] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0148] The optical lens may also include an aperture stop STO, which may be positioned between the third lens L3 and the fourth lens L4 to improve image quality.

[0149] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0150] Table 5-1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 5, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0151]

[0152] Table 5-1

[0153] In Example 5, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, and sixth lenses are aspherical. Table 5-2 shows the higher-order coefficients that can be used for each aspherical mirror surface in Example 5, wherein each conventional aspherical surface type can be defined by formula (1) given in Example 1 above.

[0154] Face number k A4 A6 A8 A10 A12 S1 -38.93 -2.46E-03 1.10E-04 -6.11E-07 0.00E+00 0.00E+00 S2 -0.77 -9.11E-03 6.89E-03 -3.97E-04 1.52E-06 0.00E+00 S3 23.88 -3.45E-03 -5.03E-03 6.06E-05 -1.43E-04 1.90E-04 S4 44.25 -3.19E-02 3.46E-03 -1.86E-03 8.92E-04 -1.52E-07 S5 -63.37 1.12E-02 -5.57E-03 6.29E-03 -1.61E-03 3.04E-04 S6 86.70 -3.52E-03 7.81E-03 -2.28E-03 1.23E-03 0.00E+00 S10 0.00 -1.08E-01 3.07E-02 -7.16E-03 1.26E-03 -9.37E-05 S11 -6.59 -3.67E-02 9.84E-03 -1.64E-03 1.69E-04 -6.15E-06 S12 -5.28 -1.14E-02 5.01E-04 1.89E-05 0.00E+00 0.00E+00 S13 -0.82 2.62E-03 1.67E-04 0.00E+00 0.00E+00 0.00E+00

[0155] Table 5-2

[0156] In summary, Examples 1 to 5 satisfy the relationships shown in Table 6 below.

[0157] Conditional Implementation Examples Example 1 Example 2 Example 3 Example 4 Example 5 -1.65≤f1 / f≤-1.25 -1.478 -1.563 -1.519 -1.590 -1.347 -0.5≤r2 / f1≤-0.2 -0.414 -0.370 -0.376 -0.367 -0.408 -0.60≤f3 / f2≤0.35 -0.109 0.227 0.199 0.266 -0.494 2.5 ≤ f³ / f ≤ 4.5 2.978 3.625 4.044 4.165 3.246 1.5≤nd2≤1.7 1.64 1.64 1.64 1.65 1.54 20≤vd2≤60 23.5 23.5 23.5 21.6 56 1.5≤nd3≤1.7 1.54 1.54 1.54 1.55 1.66 20≤vd3≤60 55.7 55.7 56 56 20.4 0.03≤CT3 / TTL≤0.15 0.083 0.089 0.067 0.068 0.053 -3.0≤fa / f≤-0.5 -1.498 -2.193 -2.090 -2.372 -1.009 1.2≤fb / f≤1.9 1.612 1.724 1.742 1.786 1.533 1.4 ≤ f⁴ / f ≤ 2.7 2.531 2.474 2.123 2.175 1.483 -2.2≤f5 / f≤-1.2 -1.859 -2.033 -1.606 -1.636 -1.365 1.3≤f6 / f≤2.1 1.626 1.908 1.656 1.652 1.434 5.3≤TTL / f≤5.9 5.638 5.747 5.637 5.715 5.479 7≤TTL / FNO≤8 7.782 7.884 7.886 7.850 7.175 0.15≤100×T45 / TTL≤3.30 0.696 0.734 3.133 1.816 1.437 2.2 ≤ BFL / TL ≤ 3.3 3.033 3.010 2.868 3.021 2.415

[0158] Table 6

[0159] This application also provides an electronic device that may include an optical lens according to the above embodiments of this application and an imaging element for converting the optical image formed by the optical lens into an electrical signal. The electronic device may be a stand-alone electronic device, such as a rangefinder camera, or an imaging module integrated into a rangefinder device. Furthermore, the electronic device may also be a stand-alone imaging device, such as an in-vehicle camera, or an imaging module integrated into a driver assistance system, such as a driving assistance system.

[0160] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical lens, characterized in that, The optical lens comprises, along the optical axis from the object side to the image side, the following in sequence: The first lens with negative optical power has a convex object side and a concave image side. A second lens with optical power has a concave object side. A third lens with positive optical power has a convex object-side surface and a convex image-side surface; The fourth lens with positive optical power has a convex object-side surface and a convex image-side surface; A fifth lens with negative optical power, its image-side surface being concave; and The sixth lens has positive optical power, with both its object-side and image-side surfaces being convex. The distance BFL from the image-side surface of the sixth lens to the imaging surface of the optical lens on the optical axis and the distance TL from the object-side surface of the first lens to the image-side surface of the sixth lens on the optical axis satisfy the following: 2.2≤BFL / TL≤3.

3.

2. The optical lens according to claim 1, characterized in that, The effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.65≤f1 / f≤-1.

25.

3. The optical lens according to claim 1, characterized in that, The radius of curvature r2 of the image side of the first lens and the effective focal length f1 of the first lens satisfy: -0.5≤r2 / f1≤-0.

2.

4. The optical lens according to claim 1, characterized in that, The effective focal length f3 of the third lens and the effective focal length f2 of the second lens satisfy the condition: -0.60≤f3 / f2≤0.

35.

5. The optical lens according to claim 1, characterized in that, The effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy the following condition: 2.5 ≤ f3 / f ≤ 4.

5.

6. The optical lens according to claim 1, characterized in that, The refractive index nd2 of the second lens satisfies: 1.5 ≤ nd2 ≤ 1.7; The refractive index nd3 of the third lens satisfies: 1.5 ≤ nd3 ≤ 1.7; The Abbe number vd2 of the second lens satisfies: 20 ≤ vd2 ≤ 60; The Abbe number vd3 of the third lens satisfies: 20≤vd3≤60.

7. The optical lens according to claim 1, characterized in that, The center thickness CT3 of the third lens on the optical axis and the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfy the following condition: 0.03≤CT3 / TTL≤0.

15.

8. The optical lens according to claim 1, characterized in that, The combined focal length fa of the first lens and the second lens satisfies the following condition with respect to the effective focal length f of the optical lens: -3.0 ≤ fa / f ≤ -0.

5.

9. The optical lens according to any one of claims 1-8, characterized in that, The combined focal length fb of the third lens, the fourth lens, the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy the following condition: 1.2 ≤ fb / f ≤ 1.

9.

10. The optical lens according to any one of claims 1-8, characterized in that, The effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy the following condition: 1.4≤f4 / f≤2.

7.

11. The optical lens according to any one of claims 1-8, characterized in that, The effective focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy the following condition: -2.2≤f5 / f≤-1.

2.

12. The optical lens according to any one of claims 1-8, characterized in that, The effective focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy the following condition: 1.3≤f6 / f≤2.

1.

13. The optical lens according to any one of claims 1-8, characterized in that, The distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis and the effective focal length f of the optical lens satisfy: 5.3≤TTL / f≤5.

9.

14. The optical lens according to any one of claims 1-8, characterized in that, The distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis and the aperture number FNO of the optical lens satisfy: 7≤TTL / FNO≤8.

15. The optical lens according to any one of claims 1-8, characterized in that, The air gap T45 between the fourth lens and the fifth lens on the optical axis and the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfy the following: 0.15≤100×T45 / TTL≤3.30.

Images