Optical lens

Abstract

This application discloses an optical lens. The optical lens, along the optical axis from the object side to the image side, sequentially includes: a first lens with negative optical power, whose image side is concave; a second lens with optical power, whose object side is concave and image side is convex; a third lens with optical power, whose object side is convex; a fourth lens with positive optical power, whose image side is convex; a fifth lens with positive optical power, whose object side and image side are both convex; a sixth lens with negative optical power, whose object side is concave; a seventh lens with positive optical power, whose object side and image side are both convex; and an eighth lens with optical power, whose object side is convex and image side is concave. The sum of the distances between any two adjacent lenses on the optical axis, ∑AT, and the distance on the optical axis from the object side of the first lens to the image plane of the optical lens, TTL, satisfy: 0.1 ≤ ∑AT / TTL ≤ 0.2.

Description

Technical Field

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

[0002] With increasing public awareness of security, surveillance lenses, acting as the "eyes" of humanity, are playing an increasingly important role in machine vision, artificial intelligence, criminal investigation monitoring, and autonomous driving, driving the development of the security monitoring field. Currently, the demands on security lenses are rising, primarily in terms of higher image quality, wider field of view, and larger aperture. In particular, a larger aperture means greater light intake, enabling clear monitoring even in low-light conditions. In other words, optical lenses with large apertures are suitable for more complex monitoring environments. Therefore, developing an optical lens with a large aperture and high imaging quality to meet the needs of security monitoring is essential. Summary of the Invention

[0003] 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, the image side of which is concave; a second lens with optical power, the object side of which is concave and the image side of which is convex; a third lens with optical power, the object side of which is convex; a fourth lens with positive optical power, the image side of which is convex; a fifth lens with positive optical power, the object side of which is convex and the image side of which is convex; a sixth lens with negative optical power, the object side of which is concave; a seventh lens with positive optical power, the object side of which is convex and the image side of which is convex; and an eighth lens with optical power, the object side of which is convex and the image side of which is concave. The sum of the distances between any two adjacent lenses in the first to eighth lenses along the optical axis, ∑AT, and the distance TTL from the object side of the first lens to the imaging plane of the optical lens along the optical axis satisfy: 0.1 ≤ ∑AT / TTL ≤ 0.2.

[0004] In one embodiment, the effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: -2.1≤F1 / F≤-1.5.

[0005] In one embodiment, the effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: 2.5≤|F2 / F|≤5.7.

[0006] In one embodiment, the effective focal length F3 of the third lens and the effective focal length F of the optical lens satisfy: 2.1≤|F3 / F|≤6.1.

[0007] In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy: 2.0≤F4 / F≤2.8.

[0008] In one embodiment, the effective focal length F5 of the fifth lens and the effective focal length F of the optical lens satisfy: 1.5≤F5 / F≤2.0.

[0009] In one embodiment, the effective focal length F6 of the sixth lens and the effective focal length F of the optical lens satisfy: -1.5≤F6 / F≤-1.3.

[0010] In one embodiment, the effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy: 1.4≤F7 / F≤3.9.

[0011] In one embodiment, the radius of curvature R81 of the object side of the eighth lens and the radius of curvature R82 of the image side of the eighth lens satisfy: 1.7≤(R81+R82) / F≤5.1.

[0012] In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy: 1.1≤F4 / F5≤1.6.

[0013] In one embodiment, the radius of curvature R42 of the image-side surface of the fourth lens and the effective focal length F4 of the fourth lens satisfy: -1.6≤R42 / F4≤-0.5.

[0014] In one embodiment, the center thickness d2 of the second 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≤d2 / TTL≤0.1.

[0015] In one embodiment, the distance d13 on the optical axis from the object side of the first lens to the image side of the third lens satisfies the following condition with respect to the effective focal length F of the optical lens: 0.2≤d13 / F≤0.4.

[0016] In one embodiment, the entrance pupil diameter ENPD of the optical lens 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: 0.1≤ENPD / TTL≤0.3.

[0017] In one embodiment, the maximum aperture D of the optical lens, the image height H corresponding to the maximum field of view of the optical lens, and the effective focal length F of the optical lens satisfy: 0.1≤D / H / F≤0.4.

[0018] In one embodiment, the back focal length BFL of the optical lens and the distance TL on the optical axis from the object side of the first lens to the image side of the eighth lens satisfy: 0.2≤BFL / TL≤0.4.

[0019] In one embodiment, the effective focal length F of the optical lens 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: 0.1≤F / TTL≤0.3.

[0020] 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: 2.4≤TTL / H≤2.6.

[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 employs eight lenses. By optimizing the shape, optical power, and other relevant parameters of each lens, the optical lens achieves at least one beneficial effect, such as a large aperture, a large image plane, and miniaturization. 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 of the structure of an optical lens according to Embodiment 1 of this application;

[0025] Figure 2 This is a schematic diagram of the structure of an optical lens according to Embodiment 2 of this application;

[0026] Figure 3 This is a schematic diagram of the structure of the optical lens according to Embodiment 3 of this application;

[0027] Figure 4 This is a schematic diagram of the structure of an optical lens according to Embodiment 4 of this application; and

[0028] Figure 5 This is a schematic diagram of 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, eight lenses with optical power, namely a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens. These eight 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 eighth 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 eighth lens. Optionally, the photosensitive element disposed on the image side of the eighth 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. Specifically, the aperture stop may be located between the second and third lenses, or it may be located on the object side of the third lens. The aperture stop helps to concentrate the light entering the optical lens, reduce the maximum aperture of the optical lens, and reduce the assembly sensitivity of the system. However, it should be noted that the location of the aperture stop disclosed herein is merely an example and not a limitation; in alternative embodiments, the aperture stop may be located at other positions as needed.

[0040] In an exemplary embodiment, the first lens has negative optical power and its image side is concave, which can diffuse the large field of view light entering the optical system to the rear optical system, effectively increasing the amount of light transmitted and improving resolution.

[0041] In an exemplary embodiment, the object-side surface of the second lens is concave, and the image-side surface is convex. The second lens can have positive or negative optical power. When the second lens has positive optical power, its object-side surface is concave and its image-side surface is convex, ensuring that the light rays emitted through the second lens still maintain an upward trend. Under the same field of view, this helps to enlarge the image plane and increases the amount of light transmitted, achieving a large aperture. When the second lens has negative optical power, it facilitates light diffusion, making the light path transition smoothly. Simultaneously, the second lens's meniscus shape, concave towards the object side, helps to collect the light rays entering through the first lens and diffuse them to the rear optical system, while also reducing the front aperture of the optical lens. The concave object-side surface of the second lens, combined with the concave image-side surface of the first lens, allows for a reduction in the front aperture of the optical lens, reducing its size and facilitating miniaturization and cost reduction.

[0042] In an exemplary embodiment, the object-side surface of the third lens is convex. The third lens may have negative optical power, which diverges light rays, dispersing the central and peripheral rays of each field of view, increasing system illumination, and facilitating the correction of aberrations between the peripheral and central rays, thus achieving high resolution. The third lens may also have positive optical power, with a convex object-side surface, which converges light rays, allowing the diverged light rays to smoothly enter the rear optical system, thereby improving resolution.

[0043] In an exemplary embodiment, the fourth lens has positive optical power and its image-side surface is convex. The positive optical power of the fourth lens allows light to smoothly transition to the fifth lens, which is beneficial for improving resolution. The convex image-side surface of the fourth lens, combined with the convex object-side surface of the fifth lens, converges light rays. This allows diverging light rays to smoothly enter the subsequent optical system while simultaneously lowering the position of the light rays incident on the subsequent optical system, thus reducing the rear aperture.

[0044] In an exemplary embodiment, the fifth lens has positive optical power, with both its object-side and image-side surfaces being convex. This configuration of the fifth lens facilitates light convergence; simultaneously, it compresses the angle of the incident light rays, allowing for a smooth transition and enabling diverging light rays to smoothly enter the rear, further smoothing the light path and facilitating a reduction in the aperture of the rear lens.

[0045] In an exemplary embodiment, the sixth lens has negative optical power and its object-side surface is concave. This configuration of the sixth lens can further reduce aberrations and improve image quality, while also ensuring that light rays converge effectively and smoothly at the final point, allowing the light to reach the image plane steadily, which is beneficial for reducing CRA.

[0046] In an exemplary embodiment, the seventh lens has positive optical power, with both its object-side and image-side surfaces being convex. This configuration of the seventh lens can further reduce aberrations and improve image quality, while also ensuring that light rays converge effectively and smoothly at the final point, allowing the light to reach the image plane steadily, thus reducing overall weight and cost.

[0047] In an exemplary embodiment, the object-side surface of the eighth lens is convex, and the image-side surface is concave. The eighth lens has positive optical power, and its convex object-side surface and concave image-side surface allow as many large-angle peripheral rays as possible to smoothly transition to the rear optical system, thereby correcting astigmatism and distortion and improving the resolving power of the optical system.

[0048] In an exemplary embodiment, the second and third lenses of the optical lens according to this application have opposite optical powers.

[0049] In an exemplary embodiment, the optical lens according to this application satisfies: 0.1 ≤ ∑AT / TTL ≤ 0.2, where ∑AT is the sum of the distances between any two adjacent lenses from the first lens to the eighth 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. Satisfying 0.1 ≤ ∑AT / TTL ≤ 0.2 can effectively reduce the size of the lens group, thereby avoiding an excessively large optical lens; at the same time, it can also reduce the assembly difficulty of the lens and achieve a higher space utilization rate.

[0050] In an exemplary embodiment, the optical lens according to this application satisfies: -2.1≤F1 / F≤-1.5, where F1 is the effective focal length of the first lens and F is the effective focal length of the optical lens. Satisfying -2.1≤F1 / F≤-1.5 allows the first lens to have a larger negative focal length, which is beneficial for controlling the angle at which light enters the optical lens and for reducing the aberration correction burden on subsequent lenses.

[0051] In an exemplary embodiment, the optical lens according to this application satisfies: 2.5 ≤ |F2 / F| ≤ 5.7, where F2 is the effective focal length of the second lens and F is the effective focal length of the optical lens. Satisfying 2.5 ≤ |F2 / F| ≤ 5.7 further diverges the light, contributing to a smoother light transition and reducing sensitivity.

[0052] In an exemplary embodiment, the optical lens according to this application satisfies: 2.1 ≤ |F3 / F| ≤ 6.1, where F3 is the effective focal length of the third lens and F is the effective focal length of the optical lens. Satisfying 2.1 ≤ |F3 / F| ≤ 6.1 helps light to smoothly transition into the third lens, reduces system sensitivity, and improves resolution.

[0053] In an exemplary embodiment, the optical lens according to this application satisfies: 2.0 ≤ F4 / F ≤ 2.8, where F4 is the effective focal length of the fourth lens and F is the effective focal length of the optical lens. Satisfying 2.0 ≤ F4 / F ≤ 2.8 allows the effective focal length of the fourth lens to remain stable over a large temperature range, resulting in excellent temperature performance and facilitating stable performance of the optical lens under temperature variations.

[0054] In an exemplary embodiment, the optical lens according to this application satisfies: 1.5 ≤ F5 / F ≤ 2.0, where F5 is the effective focal length of the fifth lens and F is the effective focal length of the optical lens. Satisfying 1.5 ≤ F5 / F ≤ 2.0 is beneficial for converging light rays while correcting astigmatism and field curvature, thereby improving resolution quality.

[0055] In an exemplary embodiment, the optical lens according to this application satisfies: -1.5≤F6 / F≤-1.3, where F6 is the effective focal length of the sixth lens and F is the effective focal length of the optical lens. Satisfying -1.5≤F6 / F≤-1.3 allows for further adjustment of light, which is beneficial for correcting chromatic aberration caused by the front optical system.

[0056] In an exemplary embodiment, the optical lens according to this application satisfies: 1.4 ≤ F7 / F ≤ 3.9, where F7 is the effective focal length of the seventh lens and F is the effective focal length of the optical lens. Satisfying 1.4 ≤ F7 / F ≤ 3.9, controlling the focal length of the seventh lens within a certain range, is beneficial for achieving rapid focusing of light onto the imaging plane, avoiding upward beams of light, reducing the rear aperture, and simultaneously improving light collection and ensuring sufficient light transmission.

[0057] In an exemplary embodiment, the optical lens according to this application satisfies: 1.7 ≤ (R81 + R82) / F ≤ 5.1, where R81 is the radius of curvature of the object-side surface of the eighth lens, R82 is the radius of curvature of the image-side surface of the eighth lens, and F is the effective focal length of the optical lens. Satisfying 1.7 ≤ (R81 + R82) / F ≤ 5.1 is beneficial for the optical lens to have both good imaging quality and low sensitivity.

[0058] In an exemplary embodiment, the optical lens according to this application satisfies: 1.1 ≤ F4 / F5 ≤ 1.6, where F4 is the effective focal length of the fourth lens and F5 is the effective focal length of the fifth lens. Satisfying 1.1 ≤ F4 / F5 ≤ 1.6 allows the fourth and fifth lenses to have relatively close focal length values, which helps to smooth the light transition and thus improves image quality.

[0059] In an exemplary embodiment, the optical lens according to this application satisfies: -1.6 ≤ R42 / F4 ≤ -0.5, where R42 is the radius of curvature of the image-side surface of the fourth lens, and F4 is the effective focal length of the fourth lens. Satisfying -1.6 ≤ R42 / F4 ≤ -0.5 controls the radius of curvature of the image-side surface of the fourth lens within a certain range. This ensures that the light rays emitted from the fourth lens enter the object-side surface of the fifth lens almost perpendicularly, resulting in a smoother light path that helps reduce light energy loss. Simultaneously, the smoother light path into the rear lenses results in fewer aberrations, which is beneficial for achieving high resolution.

[0060] In an exemplary embodiment, the optical lens according to this application satisfies: 0 ≤ d2 / TTL ≤ 0.1, where d2 is the center thickness of the second 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. Satisfying 0 ≤ d2 / TTL ≤ 0.1, by reasonably setting the center thickness of the second lens, helps to reduce sensitivity while ensuring image quality.

[0061] In an exemplary embodiment, the optical lens according to this application satisfies: 0.2 ≤ d13 / F ≤ 0.4, where d13 is the distance on the optical axis from the object-side surface of the first lens to the image-side surface of the third lens, and F is the effective focal length of the optical lens. Satisfying 0.2 ≤ d13 / F ≤ 0.4 allows for a reasonable setting of the distance on the optical axis between the object-side surface of the first lens and the image-side surface of the third lens. A distance that is too small is detrimental to achieving a large field of view, while a distance that is too large is detrimental to reducing the overall length of the system and achieving lens miniaturization.

[0062] In an exemplary embodiment, the optical lens according to this application satisfies: 0.1≤ENPD / TTL≤0.3, where ENPD is the entrance pupil diameter of the optical lens, and 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. Satisfying 0.1≤ENPD / TTL≤0.3 is beneficial for achieving a larger relative aperture, ensuring image clarity even in low-light environments or at night.

[0063] In an exemplary embodiment, the optical lens according to this application satisfies: 0.1≤D / H / F≤0.4, where D is the maximum aperture of the optical lens, H is the image height corresponding to the maximum field of view of the optical lens, and F is the effective focal length of the optical lens. Satisfying 0.1≤D / H / F≤0.4, under the condition of a fixed focal length, enables the optical lens to meet the characteristics of a large target surface and a small aperture.

[0064] In an exemplary embodiment, the optical lens according to this application satisfies: 0.2 ≤ BFL / TL ≤ 0.4, where BFL is the back focal length 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 eighth lens. Satisfying 0.2 ≤ BFL / TL ≤ 0.4 is beneficial for achieving the characteristic of a long back focal length while realizing miniaturization. This is not only beneficial for module assembly, but also helps to reduce the energy of ghost images generated by reflections from the center of the lenses and color filters while keeping the back focal length within a reasonable range.

[0065] In an exemplary embodiment, the optical lens according to this application satisfies: 0.1 ≤ F / TTL ≤ 0.3, where F is the effective focal length of the optical lens, and 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. Satisfying 0.1 ≤ F / TTL ≤ 0.3 effectively limits the length of the optical lens, achieving miniaturization of the optical lens.

[0066] In an exemplary embodiment, the optical lens according to this application satisfies: 2.4 ≤ TTL / H ≤ 2.6, 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 H is the image height corresponding to the maximum field of view of the optical lens. Satisfying 2.4 ≤ TTL / H ≤ 2.6 is beneficial for achieving a large image height under the same TTL conditions.

[0067] In an exemplary embodiment, the optical lens of this application may be made of a glass-plastic hybrid material. For example, a glass-plastic hybrid material consisting of one glass lens and seven plastic lenses may be used. This is beneficial for reducing the cost of the optical system and for balancing the high and low temperature performance of the optical lens, ensuring high imaging quality within the range of -40℃ to +80℃.

[0068] In an exemplary embodiment, the aperture number FNO of the optical lens of this application is 1.0, ensuring that the optical lens has the characteristic of a large aperture.

[0069] In an exemplary embodiment, the image height H corresponding to the maximum field of view of the optical lens of this application satisfies: H≥8.8mm, which is beneficial to achieving a large image plane imaging effect of the system, thereby possessing high optical performance and enabling the optical lens to be matched with sensors of different specifications.

[0070] In an exemplary embodiment, the distance TTL between the object side of the first lens of the optical lens and the imaging surface of the optical lens on the optical axis satisfies the following: TTL≤22.5mm, short total optical length, compact structure, which is conducive to miniaturization.

[0071] In an exemplary embodiment, the optical lens of this application may, as needed, include a filter and / or protective glass disposed between the eighth 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.

[0072] In an exemplary embodiment, the first to eighth 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. An aspherical lens is characterized by a continuously changing curvature from its center to its periphery. Unlike a spherical lens, which has a constant curvature from its center to its periphery, an aspherical lens has 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, at least one of the object-side and image-side surfaces of each of the first to eighth lenses is an aspherical mirror. Optionally, the object-side and image-side surfaces of each of the first, second, third, fifth, sixth, seventh, and eighth lenses are both aspherical mirrors, while the object-side and image-side surfaces of the fourth lens are spherical mirrors.

[0073] The optical lens according to the above embodiments of this application may employ multiple lenses, such as the eight lenses described above. However, those skilled in the art should understand that the number of lenses constituting the lens can be changed without departing from the technical solutions claimed in this application to obtain the various results and advantages described in this specification. For example, although eight lenses have been described as an example in the embodiments, the optical lens is not limited to including eight 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.

[0074] Example 1

[0075] 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.

[0076] 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, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis.

[0077] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0078] The second lens L2 has positive optical power, with its object side S3 being concave and its image side S4 being convex.

[0079] The third lens L3 has negative optical power, with its object side S6 being convex and its image side S7 being concave.

[0080] The fourth lens L4 has positive optical power, with its object side S8 being a plane and its image side S9 being a convex surface.

[0081] The fifth lens L5 has positive optical power, and its object side S10 is convex, and its image side S11 is convex.

[0082] The sixth lens L6 has negative optical power, and its object side S12 is concave, and its image side S13 is concave.

[0083] The seventh lens L7 has positive optical power, and its object side S14 is convex, and its image side S15 is convex.

[0084] The eighth lens L8 has negative optical power, with its object side S16 being convex and its image side S17 being concave.

[0085] 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.

[0086] Optionally, the optical lens may also include a filter CG having an object-side surface S18 and an image-side surface S19 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 S19 and is ultimately imaged onto the imaging surface.

[0087] Table 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).

[0088]

[0089]

[0090] Table 1

[0091] In Example 1, the fourth lens is a spherical lens. The object-side surface and image-side surface of any one of the first, second, third, fifth, sixth, seventh, and eighth lenses are aspherical. The surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0092]

[0093] 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 2 gives the higher-order coefficients A4, A6, A8, A1, A2, A3, A4, A5, A6, A8, A9, A1, A1, A1, A2 ...1, A1, A1, A1, A1, A1, A1, A1, A1, A1, A1, A1, A1 10 A 12 and A 14 .

[0094]

[0095]

[0096] Table 2

[0097] Example 2

[0098] 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 2A schematic diagram of the structure of an optical lens according to Embodiment 2 of this application is shown.

[0099] 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, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis.

[0100] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0101] The second lens L2 has positive optical power, with its object side S3 being concave and its image side S4 being convex.

[0102] The third lens L3 has negative optical power, with its object side S6 being convex and its image side S7 being concave.

[0103] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0104] The fifth lens L5 has positive optical power, and its object side S10 is convex, and its image side S11 is convex.

[0105] The sixth lens L6 has negative optical power, and its object side S12 is concave, and its image side S13 is concave.

[0106] The seventh lens L7 has positive optical power, and its object side S14 is convex, and its image side S15 is convex.

[0107] The eighth lens L8 has negative optical power, with its object side S16 being convex and its image side S17 being concave.

[0108] 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.

[0109] Optionally, the optical lens may also include a filter CG having an object-side surface S18 and an image-side surface S19 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 S19 and is ultimately imaged onto the imaging surface.

[0110] Table 3 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).

[0111]

[0112]

[0113] Table 3

[0114] 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, sixth, seventh, and eighth lenses are aspherical. Table 4 shows the higher-order coefficients that can be used for each aspherical mirror in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0115] Face number k A4 A6 A8 A10 A12 A14 S1 0.00 -9.58E-03 6.93E-04 -3.06E-05 7.71E-07 -8.40E-09 0.00E+00 S2 -2.84 1.39E-03 -3.09E-04 6.84E-05 -5.24E-06 1.57E-07 0.00E+00 S3 0.11 2.33E-03 -5.11E-04 1.45E-05 -8.08E-07 6.01E-08 0.00E+00 S4 -0.28 7.33E-03 -1.11E-03 7.85E-05 -3.59E-06 9.88E-08 0.00E+00 S6 0.00 -1.86E-03 -7.32E-06 -1.18E-05 1.38E-06 -3.45E-08 0.00E+00 S7 -19.59 -3.02E-03 1.70E-04 -1.10E-05 5.26E-07 -8.72E-09 0.00E+00 S10 -1.98 -1.28E-03 5.60E-05 -3.69E-06 1.92E-07 -3.21E-09 0.00E+00 S11 1.99 -1.28E-03 -2.27E-06 1.49E-07 -8.83E-09 1.38E-09 0.00E+00 S12 -0.05 5.22E-03 -2.99E-04 1.51E-05 -5.72E-07 1.11E-08 0.00E+00 S13 -30.14 3.17E-03 -3.75E-04 3.80E-05 -1.93E-06 3.63E-08 0.00E+00 S14 -37.47 2.28E-03 -4.54E-04 5.26E-05 -2.66E-06 5.04E-08 0.00E+00 S15 -1.46 4.18E-03 -3.35E-04 2.38E-05 -1.04E-06 2.06E-08 0.00E+00 S16 -0.37 -4.70E-03 1.81E-04 -1.18E-05 2.27E-07 -9.94E-10 0.00E+00 S17 -6.66 -2.45E-03 1.41E-04 -1.26E-05 4.20E-07 -5.27E-09 0.00E+00

[0116] Table 4

[0117] Example 3

[0118] 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.

[0119] 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, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis.

[0120] The first lens L1 has negative optical power, and its object side S1 is concave, and its image side S2 is concave.

[0121] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0122] The third lens L3 has positive optical power, and its object side S5 is convex, while its image side S6 is convex.

[0123] The fourth lens L4 has positive optical power, with its object side S7 being a plane and its image side S8 being a convex surface.

[0124] The fifth lens L5 has positive optical power, and its object side S9 is convex, and its image side S10 is convex.

[0125] The sixth lens L6 has negative optical power, and its object side S11 is concave, and its image side S12 is concave.

[0126] The seventh lens L7 has positive optical power, and its object side S13 is convex, and its image side S14 is convex.

[0127] The eighth lens L8 has negative optical power, with its object side S15 being convex and its image side S16 being concave.

[0128] The optical lens may also include an aperture stop STO (not shown), which may be set on the object side of the third lens L3 to improve image quality.

[0129] Optionally, the optical lens may also include a filter CG having an object-side surface S17 and an image-side surface S18 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 deviations, 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 S18 and is finally imaged onto the imaging surface.

[0130] Table 5 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).

[0131]

[0132] Table 5

[0133] 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, sixth, seventh, and eighth lenses are aspherical. Table 6 shows the higher-order coefficients that can be used for each aspherical mirror in Example 3, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0134] Face number k A4 A6 A8 A10 A12 A14 A16 S1 45.85 2.54E-04 1.64E-06 -8.48E-08 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S2 -6.58 1.34E-02 -1.55E-03 2.48E-04 -2.80E-05 2.53E-06 -1.59E-07 6.06E-09 S3 -10.65 -1.08E-03 3.02E-04 -7.74E-05 7.53E-06 -2.48E-07 -9.66E-09 5.05E-10 S4 -33.72 2.29E-03 1.66E-04 -5.06E-05 3.10E-06 -1.43E-08 -5.24E-09 -6.99E-11 S5 -27.45 -1.86E-03 8.28E-05 3.66E-06 -1.87E-06 -2.47E-08 1.99E-08 -1.10E-09 S6 10.64 -6.50E-03 4.89E-04 -3.85E-05 1.56E-06 -2.06E-09 -2.91E-09 5.16E-11 S9 0.27 -2.45E-03 2.72E-06 -4.70E-06 3.98E-07 -1.99E-08 5.11E-10 -4.49E-13 S10 4.86 1.62E-03 -2.38E-04 1.09E-05 8.53E-08 -1.29E-08 -4.09E-10 2.89E-11 S11 -5.41 2.21E-03 -1.50E-04 2.59E-06 1.83E-07 1.34E-11 -1.02E-09 2.88E-11 S12 19.01 1.32E-03 2.03E-04 -2.63E-05 1.19E-06 8.64E-09 -2.70E-09 6.21E-11 S13 6.36 6.79E-05 1.83E-04 -2.16E-05 1.08E-06 -3.11E-09 -1.96E-09 5.33E-11 S14 -8.53 -1.76E-03 9.69E-05 -5.24E-06 -2.86E-07 4.89E-08 -2.60E-09 5.36E-11 S15 -0.02 -6.00E-03 -1.16E-05 -5.83E-06 4.19E-07 -7.12E-08 4.91E-09 -9.72E-11 S16 -7.46 -2.54E-03 -6.07E-05 -1.20E-06 2.61E-08 2.21E-08 -1.24E-09 2.25E-11

[0135] Table 6

[0136] Example 4

[0137] 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.

[0138] 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, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis.

[0139] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0140] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0141] The third lens L3 has positive optical power, with its object side S5 being convex and its image side S6 being concave.

[0142] The fourth lens L4 has positive optical power, and its object side S7 is convex, while its image side S8 is convex.

[0143] The fifth lens L5 has positive optical power, and its object side S9 is convex, and its image side S10 is convex.

[0144] The sixth lens L6 has negative optical power, and its object side S11 is concave, and its image side S12 is concave.

[0145] The seventh lens L7 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0146] The eighth lens L8 has positive optical power, with its object side S14 being convex and its image side S15 being concave.

[0147] The sixth and seventh lenses are cemented lenses, and the image-side surface S12 of the sixth lens and the object-side surface of the seventh lens are shared. The optical lens may also include an aperture stop STO (not shown), which may be set on the object-side surface of the third lens L3 to improve image quality.

[0148] Optionally, the optical lens may also include a filter CG having an object-side surface S16 and an image-side surface S17 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 deviations, 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 S17 and is ultimately imaged onto the imaging surface.

[0149] Table 7 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).

[0150]

[0151] Table 7

[0152] 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, sixth, seventh, and eighth lenses are aspherical. Table 8 shows the higher-order coefficients that can be used for each aspherical mirror in Example 4, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0153]

[0154]

[0155] Table 8

[0156] Example 5

[0157] 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.

[0158] 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, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis.

[0159] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0160] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0161] The third lens L3 has positive optical power, with its object side S5 being convex and its image side S6 being concave.

[0162] The fourth lens L4 has positive optical power, and its object side S7 is convex, while its image side S8 is convex.

[0163] The fifth lens L5 has positive optical power, and its object side S9 is convex, and its image side S10 is convex.

[0164] The sixth lens L6 has negative optical power, with its object side S11 being concave and its image side S12 being convex.

[0165] The seventh lens L7 has positive optical power, and its object side S13 is convex, and its image side S14 is convex.

[0166] The eighth lens L8 has positive optical power, with its object side S15 being convex and its image side S16 being concave.

[0167] The optical lens may also include an aperture stop STO (not shown), which may be set on the object side of the third lens L3 to improve image quality.

[0168] Optionally, the optical lens may also include a filter CG having an object-side surface S17 and an image-side surface S18 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 deviations, 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 S18 and is finally imaged onto the imaging surface.

[0169] Table 9 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).

[0170]

[0171]

[0172] Table 9

[0173] 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, sixth, seventh, and eighth lenses are aspherical. Table 10 shows the higher-order coefficients that can be used for each aspherical mirror in Example 5, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0174] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -58.48 -6.00E-04 3.01E-05 -5.75E-07 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S2 -3.84 1.19E-02 -1.08E-03 1.22E-04 -6.74E-06 2.46E-07 -1.57E-08 1.82E-09 S3 -5.12 -4.49E-03 5.41E-05 1.72E-05 -2.78E-06 2.82E-07 -8.16E-09 -5.34E-10 S4 -8.29 -3.01E-03 4.44E-05 -3.15E-07 6.24E-07 -4.74E-08 1.87E-10 -1.03E-10 S5 -11.81 -2.77E-04 5.38E-05 1.43E-06 -1.91E-07 1.17E-09 3.74E-10 -1.49E-11 S6 -17.43 -1.09E-03 8.66E-05 -2.41E-06 8.91E-08 1.22E-09 -2.81E-10 3.76E-12 S9 -0.33 -2.66E-03 1.26E-04 -1.13E-05 5.85E-07 -2.10E-08 6.97E-10 -2.05E-11 S10 2.76 1.02E-03 -4.39E-05 2.54E-06 6.28E-09 -1.25E-09 -2.25E-11 6.03E-12 S11 -4.58 2.64E-03 -1.29E-04 6.59E-08 -2.72E-08 9.12E-09 -2.97E-10 7.06E-12 S12 19.12 4.48E-03 1.22E-04 -8.03E-07 -1.09E-06 2.93E-08 -1.02E-10 1.94E-11 S13 -33.96 2.39E-04 2.38E-04 6.51E-07 -8.39E-07 1.23E-08 2.06E-09 -6.21E-11 S14 -42.47 -1.88E-03 -4.12E-05 2.01E-05 -1.35E-06 3.53E-08 3.33E-09 -1.15E-10 S15 -0.02 -8.54E-03 2.85E-04 -3.04E-05 1.69E-06 -9.78E-09 -2.10E-10 -6.71E-11 S16 -34.17 -8.07E-04 -2.51E-04 1.50E-05 -3.93E-07 9.14E-09 -1.54E-11 -2.12E-11

[0175] Table 10

[0176] In summary, Examples 1 to 5 respectively satisfy the relationships shown in Table 11 below.

[0177]

[0178]

[0179] Table 11

[0180] 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 an 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 vehicle-mounted camera.

[0181] 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 concave image-side surface. The second lens with optical power has a concave object side and a convex image side; A third lens with optical power has a convex object side. The fourth lens has positive optical power and its image-side surface is convex. A fifth lens with positive optical power, having a convex object-side surface and a convex image-side surface; and The sixth lens has negative optical power and its object side is concave. The seventh lens with positive optical power has a convex object-side surface and a convex image-side surface. The eighth lens, which has optical power, has a convex object side and a concave image side. The optical lens contains eight lenses with optical power. The second lens has positive optical power, and the third and eighth lenses both have negative optical power; or The second lens has negative optical power, the third lens has positive optical power, and the eighth lens has either positive or negative optical power. The sum of the distances between any two adjacent lenses from the first lens to the eighth lens on the optical axis, ∑AT, 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: 0.1≤∑AT / TTL≤0.2; The effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy the following condition: 1.495≤F7 / F≤3.

819.

2. The optical lens according to claim 1, wherein, The effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: -1.971≤F1 / F≤-1.

5.

3. The optical lens according to claim 1, wherein, The effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: 3.102≤|F2 / F|≤5.

587.

4. The optical lens according to claim 1, wherein, The effective focal length F3 of the third lens and the effective focal length F of the optical lens satisfy the following condition: 2.856≤|F3 / F|≤5.

964.

5. The optical lens according to claim 1, wherein, The effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy the following condition: 2.0≤F4 / F≤2.

8.

6. The optical lens according to claim 1, wherein, The effective focal length F5 of the fifth lens and the effective focal length F of the optical lens satisfy the following condition: 1.5≤F5 / F≤1.

885.

7. The optical lens according to claim 1, wherein, The effective focal length F6 of the sixth lens and the effective focal length F of the optical lens satisfy the following condition: -1.435≤F6 / F≤-1.

354.

8. The optical lens according to any one of claims 1-7, wherein, The radius of curvature R81 of the object side of the eighth lens and the radius of curvature R82 of the image side of the eighth lens satisfy: 1.7≤(R81+R82) / F≤5.

002.

9. The optical lens according to any one of claims 1-7, wherein, The effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy the following condition: 1.243≤F4 / F5≤1.

541.

10. The optical lens according to any one of claims 1-7, wherein, The radius of curvature R42 of the image side surface of the fourth lens and the effective focal length F4 of the fourth lens satisfy the following condition: -1.457≤R42 / F4≤-0.

695.

11. The optical lens according to any one of claims 1-7, wherein, The center thickness d2 of the second 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: 0.038≤d2 / TTL≤0.

1.

12. The optical lens according to any one of claims 1-7, wherein, The distance d13 from the object side of the first lens to the image side of the third lens on the optical axis satisfies the following condition: 0.265≤d13 / F≤0.

303.

13. The optical lens according to any one of claims 1-7, wherein, The entrance pupil diameter ENPD of the optical lens 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: 0.180≤ENPD / TTL≤0.

3.

14. The optical lens according to any one of claims 1-7, wherein, The maximum aperture D of the optical lens, the image height H corresponding to the maximum field of view of the optical lens, and the effective focal length F of the optical lens satisfy the following condition: 0.186≤D / H / F≤0.

255.

15. The optical lens according to any one of claims 1-7, wherein, The back focal length BFL of the optical lens and the distance TL from the object side of the first lens to the image side of the eighth lens on the optical axis satisfy: 0.2≤BFL / TL≤0.

265.

16. The optical lens according to any one of claims 1-7, wherein, The effective focal length F of the optical lens 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: 0.197≤F / TTL≤0.

240.

17. The optical lens according to any one of claims 1-7, wherein, 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 image height H corresponding to the maximum field of view of the optical lens satisfy: 2.545≤TTL / H≤2.6.

Images