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 positive refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with positive refractive power, a fifth lens with negative refractive power, a sixth lens with positive refractive power, a seventh lens with positive refractive power, an eighth lens with negative refractive power, and a ninth lens with negative refractive power.

Description

Technical Field

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

[0002] Machine vision inspection technology boasts advantages such as high efficiency, non-contact operation, and high accuracy, leading to its increasingly widespread application in fields such as industry, agriculture, medicine, robot navigation, and satellite remote sensing. The machine vision lens is the core component responsible for imaging in machine vision and is an indispensable part of the machine vision industry chain; the quality of the lens directly affects the overall performance of the vision system.

[0003] Currently, higher demands are being placed on machine vision lenses. For example: 1) The resolution of traditional machine vision lenses is insufficient for recognizing textiles and similarly sized small objects, thus requiring high resolution; 2) The assembly of machine vision lenses needs to consider the available space, thus requiring a wide working distance; 3) Considering nighttime usage scenarios, requirements are placed on the infrared performance of the lenses; 4) To meet measurement accuracy requirements and reduce the difficulty of subsequent recognition, low distortion is required; 5) To provide a wider field of view at the same focal length, a large target area is required. In other words, current traditional machine vision lenses still suffer from problems such as low resolution, narrow working distance, poor infrared performance, large optical distortion, and small target area. Summary of the Invention

[0004] This application provides an optical lens that, along the optical axis from the object side to the image side, sequentially includes: a first lens having positive optical power; a second lens having negative optical power; a third lens having positive optical power; a fourth lens having positive optical power; a fifth lens having negative optical power; a sixth lens having positive optical power; a seventh lens having positive optical power; an eighth lens having negative optical power; and a ninth lens having negative optical power.

[0005] In one embodiment, the object-side surface of the first lens is convex, and the image-side surface is convex; the object-side surface of the second lens is concave, and the image-side surface is concave; the object-side surface of the third lens is convex, and the image-side surface is convex; the object-side surface of the fourth lens is concave, and the image-side surface is convex; the object-side surface of the fifth lens is concave; the object-side surface of the sixth lens is concave, and the image-side surface is convex; the object-side surface of the seventh lens is concave, and the image-side surface is convex; the object-side surface of the eighth lens is concave; and the object-side surface of the ninth lens is concave, and the image-side surface is concave.

[0006] In one embodiment, the effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: 0.8≤F1 / F≤1.1.

[0007] In one embodiment, the effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: -2.1≤F2 / F≤-1.3.

[0008] 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≤2.9.

[0009] In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy: 12.0≤F4 / F≤14.5.

[0010] In one embodiment, the effective focal length F5 of the fifth lens and the effective focal length F of the optical lens satisfy: -7≤F5 / F≤-4.5.

[0011] In one embodiment, the effective focal length F6 of the sixth lens and the effective focal length F of the optical lens satisfy: 2.1≤F6 / F≤6.4.

[0012] In one embodiment, the effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy: 0.9≤F7 / F≤1.4.

[0013] In one embodiment, the effective focal length F8 of the eighth lens and the effective focal length F of the optical lens satisfy: -7.2≤F8 / F≤-2.4.

[0014] In one embodiment, the effective focal length F9 of the ninth lens and the effective focal length F of the optical lens satisfy: -0.7≤F9 / F≤-0.4.

[0015] In one embodiment, the maximum aperture Dmax 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: 0.4≤Dmax / TTL≤0.7.

[0016] 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: 1.4≤TTL / F≤1.6.

[0017] In one embodiment, the effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy the following condition: 2.1≤F / ENPD≤2.4.

[0018] In one implementation, the half-image height H of the optical lens and the effective focal length F of the optical lens satisfy: 0.5≤H / F≤0.6.

[0019] In one embodiment, the combined focal length F12 of the first lens and the second lens and the effective focal length F of the optical lens satisfy: 1.6≤F12 / F≤1.8.

[0020] In one embodiment, the Abbe number VD2 of the second lens satisfies: 20 ≤ VD2 ≤ 30.

[0021] In one implementation, the Abbe number VD4 of the fourth lens satisfies: 90 ≤ VD4 ≤ 100.

[0022] In one embodiment, the distance T45 on the optical axis from the image-side surface of the fourth lens to the object-side surface of the fifth lens satisfies: 0 mm ≤ T45 ≤ 0.8 mm. The distance T45 on the optical axis from the image-side surface of the fourth lens to the object-side surface of the fifth lens and the distance TTL on the optical axis from the object-side surface of the first lens to the imaging plane of the optical lens satisfy: 0 ≤ T45 / TTL ≤ 0.1. Attached Figure Description

[0023] Other features, objects, and advantages of this 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 an optical lens according to Embodiment 3 of this application; and

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

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] The features, principles and other aspects of this application are described in detail below.

[0036] In an exemplary embodiment, the optical lens includes, for example, nine 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, an eighth lens, and a ninth lens. These nine 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 the ninth lenses may have a gap distance between them.

[0037] In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the image side of the ninth lens. Optionally, the photosensitive element disposed on the image side of the ninth lens may be a photosensitive coupling element (CCD) or a complementary metal oxide semiconductor element (CMOS).

[0038] In an exemplary embodiment, the optical lens may further include an aperture stop for limiting the light beam to further improve the image quality of the optical lens. Exemplarily, the aperture stop may be positioned between the fourth and fifth 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 positioned at other locations as needed.

[0039] In an exemplary embodiment, the first lens has positive optical power and has the function of collecting light, so that the light emitted from the first lens is closer to the optical axis, which is beneficial to reducing the front port diameter of the optical lens.

[0040] In an exemplary embodiment, the first lens has positive optical power, and both the object-side and image-side surfaces are convex. The object-side and image-side surfaces share the optical power, which helps to reduce surface curvature and ensure the machinability of the parts, reduce the generation of aberrations, reduce optical distortion, and help to achieve high image quality.

[0041] In an exemplary embodiment, the first lens and the second lens can form a cemented lens. The first lens has positive optical power in the cemented lens and works with the second lens to achieve apochromatic effect, which is beneficial for achieving infrared confocal lens.

[0042] In an exemplary embodiment, the second lens has negative optical power, and both its object-side and image-side surfaces are concave. The object-side and image-side surfaces share the optical power, which helps to reduce surface curvature, reduce aberrations, and achieve high image quality.

[0043] In an exemplary embodiment, the second lens may be made of a low Abbe number material to reduce chromatic aberration, thereby reducing the difficulty of chromatic aberration correction in optical lenses and facilitating the achievement of high image quality.

[0044] In an exemplary embodiment, the first lens and the second lens can form a cemented lens, which is beneficial for correcting chromatic aberration of optical lenses, improving the color reproduction of lenses, and reducing tolerance sensitivity.

[0045] In an exemplary embodiment, the third lens has positive optical power, and both its object-side and image-side surfaces are convex, which is beneficial for collecting light, increasing light transmission, and improving relative illumination. By rationally setting the optical power and surface shape of the third lens, it is beneficial to control the light path, allowing the light to enter the system behind the aperture smoothly, which is beneficial for achieving high image quality.

[0046] In an exemplary embodiment, the fourth lens has positive optical power and its object side is concave, which can reduce the incident angle of off-axis rays on the image side of the fourth lens, thus helping to reduce off-axis aberrations generated by the optical lens.

[0047] In an exemplary embodiment, the fourth lens has positive optical power, with its object side being concave and its image side being convex.

[0048] In an exemplary embodiment, the fourth lens may be made of an anomalous dispersion material to reduce chromatic aberration in the optical lens, which is beneficial for achieving infrared confocal focusing.

[0049] In an exemplary embodiment, the fifth lens has negative optical power and its object side is concave, which can reduce the incident angle of off-axis rays on the image side of the fifth lens, thus helping to reduce off-axis aberrations generated by the optical lens.

[0050] In an exemplary embodiment, the fifth lens has negative optical power, its object side is concave, and its image side can be concave or convex. The positive spherical aberration introduced by the image side can effectively correct the negative spherical aberration generated by the object side.

[0051] In an exemplary embodiment, the sixth lens has positive optical power, with its object side being concave and its image side being convex. This reduces the incident angle of off-axis rays on the image side of the sixth lens, which is beneficial for reducing off-axis aberrations generated by the optical lens.

[0052] In an exemplary embodiment, the sixth lens has a positive optical power, its object side is concave, and its image side is convex. The positive spherical aberration introduced by the image side can effectively correct the negative spherical aberration generated by the object side.

[0053] In an exemplary embodiment, the seventh lens has positive optical power. The seventh lens can share the optical power of the sixth lens and play the role of converging light, so that the light from each field of view can smoothly enter the rear, and further make the light path transition smoothly.

[0054] In an exemplary embodiment, the seventh lens has positive optical power, with its object side being concave and its image side being convex. The positive spherical aberration introduced by the image side can effectively correct the negative spherical aberration generated by the object side.

[0055] In an exemplary embodiment, the eighth lens has negative optical power, has a small light refraction capability for light rays on the optical axis, and a large light refraction capability for light rays outside the optical axis, which is beneficial for increasing the target surface area.

[0056] In an exemplary embodiment, the eighth lens has negative optical power, its object side is concave, and its image side can be either concave or convex. When the image side of the eighth lens is concave, it is beneficial for correcting off-axis aberrations of the optical lens; when the image side of the eighth lens is convex, it is beneficial for reducing distortion and minimizing changes in light refraction, thus helping to reduce sensitivity.

[0057] In an exemplary embodiment, the negative distortion introduced by the image-side surface of the eighth lens can effectively correct the positive distortion produced by the sixth and seventh lenses.

[0058] In an exemplary embodiment, the ninth lens has negative optical power, has a small light refraction capability for light rays on the optical axis, and a large light refraction capability for light rays outside the optical axis, which is beneficial for increasing the target surface area.

[0059] In an exemplary embodiment, the ninth lens has negative optical power, and both its object-side and image-side surfaces are concave, with potential curvature on both surfaces. This is beneficial for increasing the principal ray angle at the edge of the field of view to match a large target chip, while also contributing to a more compact optical lens structure. Furthermore, the rational setting of the optical power and surface shape of the ninth lens helps correct off-axis aberrations and reduce distortion, achieving high image quality.

[0060] In an exemplary embodiment, the optical lens according to this application satisfies: 0.8 ≤ F1 / F ≤ 1.1, where F1 is the effective focal length of the first lens and F is the effective focal length of the optical lens. Satisfying 0.8 ≤ F1 / F ≤ 1.1, by reasonably allocating the focal length value of the first lens, can converge the incident light rays, making the outgoing light rays of the first lens closer to the optical axis direction, which is beneficial to reducing the front port diameter of the optical lens.

[0061] In an exemplary embodiment, the optical lens according to this application satisfies: -2.1 ≤ F2 / F ≤ -1.3, where F2 is the effective focal length of the second lens and F is the effective focal length of the optical lens. Satisfying -2.1 ≤ F2 / F ≤ -1.3, by reasonably allocating the focal length value of the second lens, allows the second lens to have negative optical power within the cemented lens composed of the first and second lenses. This is beneficial for correcting chromatic aberration in the optical lens, improving the lens's color reproduction, and simultaneously reducing tolerance sensitivity.

[0062] In an exemplary embodiment, the optical lens according to this application satisfies: 2.5 ≤ F3 / F ≤ 2.9, 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 ≤ 2.9, by reasonably allocating the focal length value of the third lens, is beneficial for controlling the light path, allowing the light to smoothly enter the system behind the aperture stop, and thus contributing to high image quality.

[0063] In an exemplary embodiment, the optical lens according to this application satisfies: 12.0 ≤ F4 / F ≤ 14.5, where F4 is the effective focal length of the fourth lens and F is the effective focal length of the optical lens. By satisfying 12.0 ≤ F4 / F ≤ 14.5 and rationally allocating the focal length value of the fourth lens, the incident angle of off-axis rays on the image side of the fourth lens can be reduced, thus minimizing aberrations caused by excessively steep light paths and contributing to high image quality.

[0064] In an exemplary embodiment, the optical lens according to this application satisfies: -7≤F5 / F≤-4.5, where F5 is the effective focal length of the fifth lens and F is the effective focal length of the optical lens. Satisfying -7≤F5 / F≤-4.5, by reasonably allocating the focal length value of the fifth lens, can reduce the incident angle of off-axis rays on the image side of the fifth lens, which is beneficial to reducing off-axis aberrations generated by the optical lens.

[0065] In an exemplary embodiment, the optical lens according to this application satisfies: 2.1≤F6 / F≤6.4, where F6 is the effective focal length of the sixth lens and F is the effective focal length of the optical lens. Satisfying 2.1≤F6 / F≤6.4, by reasonably allocating the focal length value of the sixth lens, can reduce the incident angle of off-axis rays on the image side of the sixth lens, which is beneficial to reducing off-axis aberrations generated by the optical lens.

[0066] In an exemplary embodiment, the optical lens according to this application satisfies: 0.9 ≤ F7 / F ≤ 1.4, where F7 is the effective focal length of the seventh lens and F is the effective focal length of the optical lens. By satisfying 0.9 ≤ F7 / F ≤ 1.4 and reasonably allocating the focal length value of the seventh lens, the optical power of the sixth lens can be shared, thus converging the incident light rays and allowing light from each field of view to smoothly enter the rear system, further ensuring a smooth transition of light paths.

[0067] In an exemplary embodiment, the optical lens according to this application satisfies: -7.2 ≤ F8 / F ≤ -2.4, where F8 is the effective focal length of the eighth lens and F is the effective focal length of the optical lens. Satisfying -7.2 ≤ F8 / F ≤ -2.4, by reasonably allocating the focal length value of the eighth lens, is beneficial for correcting off-axis aberrations, and the negative distortion introduced by the eighth lens can effectively correct the positive distortion generated by the sixth and seventh lenses.

[0068] In an exemplary embodiment, the optical lens according to this application satisfies: -0.7≤F9 / F≤-0.4, where F9 is the effective focal length of the ninth lens and F is the effective focal length of the optical lens. Satisfying -0.7≤F9 / F≤-0.4, by reasonably allocating the focal length value of the ninth lens, is beneficial for correcting off-axis aberrations and reducing distortion, thereby achieving high image quality.

[0069] In an exemplary embodiment, the optical lens according to this application satisfies: 0.4 ≤ Dmax / TTL ≤ 0.7, where Dmax is the maximum aperture 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. By satisfying 0.4 ≤ Dmax / TTL ≤ 0.7, and given a certain total optical length, controlling the maximum aperture of the optical lens by controlling the system results in a smaller maximum aperture, which is beneficial for miniaturization.

[0070] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 1.4 ≤ TTL / F ≤ 1.6, 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 F is the effective focal length of the optical lens. Satisfying 1.4 ≤ TTL / F ≤ 1.6, under a given focal length value, allows for a smaller overall optical length of the optical lens by controlling its overall optical length, which is beneficial for miniaturization.

[0071] In an exemplary embodiment, the optical lens according to this application satisfies: 2.1 ≤ F / ENPD ≤ 2.4, where F is the effective focal length of the optical lens and ENPD is the entrance pupil diameter of the optical lens. Satisfying 2.1 ≤ F / ENPD ≤ 2.4 allows the optical lens to have a smaller aperture value, which is beneficial for achieving a large aperture.

[0072] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 0.5 ≤ H / F ≤ 0.6, where H is the half-image height of the optical lens and F is the effective focal length of the optical lens. Satisfying 0.5 ≤ H / F ≤ 0.6, under a given system focal length value, controls the half-image height of the optical lens to meet the above range, which is beneficial for the optical lens to achieve imaging characteristics of a larger target surface.

[0073] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 1.6 ≤ F12 / F ≤ 1.8, where F12 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 1.6 ≤ F12 / F ≤ 1.8, by optimizing the combined focal length values ​​of the first and second lenses, apochromatic aberration is achieved in the optical lens, which is beneficial for achieving infrared confocal focusing. Simultaneously, it helps reduce the generation of various aberrations, achieves high image quality, and reduces tolerance sensitivity.

[0074] In an exemplary embodiment, the optical lens according to this application satisfies: 20≤VD2≤30, where VD2 is the Abbe number of the second lens. Satisfying 20≤VD2≤30, by reasonably setting the Abbe number of the second lens, can reduce the generation of chromatic aberration, reduce the difficulty of chromatic aberration correction of the optical lens, and facilitate the realization of infrared confocal focusing.

[0075] In an exemplary embodiment, the optical lens according to this application satisfies: 90≤VD4≤100, where VD4 is the Abbe number of the fourth lens. Satisfying 90≤VD4≤100, by reasonably setting the Abbe number of the fourth lens, can reduce the generation of chromatic aberration, reduce the difficulty of chromatic aberration correction of the optical lens, and facilitate the realization of infrared confocal focusing.

[0076] In an exemplary embodiment, the optical lens according to this application satisfies: 0mm ≤ T45 ≤ 0.8mm, where T45 is the distance on the optical axis from the image-side surface of the fourth lens to the object-side surface of the fifth lens. Furthermore, the optical lens according to this application also satisfies: 0 ≤ T45 / TTL ≤ 0.1, 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. By satisfying 0mm ≤ T45 ≤ 0.8mm and 0 ≤ T45 / TTL ≤ 0.1, and by changing the distance on the optical axis from the image-side surface of the fourth lens to the object-side surface of the fifth lens (i.e., changing the value of T45), clear imaging at different object distances can be achieved. The working distance range (i.e., object distance) of the optical lens of this application can be from 0.3m to infinity. Simultaneously, by changing the value of T45, the infrared defocus can be corrected, which is beneficial for achieving clear infrared focusing and broadens the application scenarios of this application. More specifically, T45 and TTL can further satisfy 0.05mm≤T45≤0.8mm and 0.001≤T45 / TTL≤0.1.

[0077] In an exemplary embodiment, the optical lens of this application can adjust the distance on the optical axis between the image side of the fourth lens and the object side of the fifth lens in real time according to the change of object distance. More specifically, the distance on the optical axis between the image side of the fourth lens and the object side of the fifth lens can be changed in the range of 0mm to 0.8mm, so that the optical lens can achieve clear imaging in the range of object distance from 0.3m to infinity.

[0078] 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 structure of 3 glass lenses and 6 plastic lenses may be used. By reasonably matching the optical power of each lens and the matching of each lens material, it can avoid defocusing within a temperature change range of -20℃ to 80℃, which is beneficial to improving the stability of the optical lens operation. Furthermore, the optical lens of this application may also be made of plastic aspherical lenses, which is beneficial to improving the image quality while reducing costs.

[0079] In an exemplary embodiment, the maximum imaging surface of the optical lens of this application is φ12.4mm, that is, the holographic height of the optical lens of this application is 12.4mm.

[0080] MTF (Modulation Transfer Function) is a quantitative evaluation index of lens optical performance, used to describe the contrast of light transmitted at different spatial frequencies, and its unit is line pairs per millimeter (lp / mm). In the exemplary embodiment, the MTF value of the optical lens of this application across the entire field of view is >0.1@417lp / mm.

[0081] In an exemplary embodiment, the optical lens of this application has the characteristic of high resolution, and its pixels can reach 48 million when the corresponding maximum imaging chip is 1 / 1.3”.

[0082] In an exemplary embodiment, the full field-of-view distortion of the optical lens of this application is <2%.

[0083] In an exemplary embodiment, the optical lens of this application may, as needed, include a filter and / or protective glass disposed between the ninth lens and the imaging surface. The filter can filter light of different wavelengths, and the protective glass can prevent damage to the image-side elements (e.g., chips) of the optical lens.

[0084] In an exemplary embodiment, the first to ninth 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 use aspherical lenses. 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 aberrations 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 ninth lenses is an aspherical mirror surface. Optionally, the object-side and image-side surfaces of each of the third, fifth, sixth, seventh, eighth, and ninth lenses are both aspherical mirror surfaces, while the object-side and image-side surfaces of each of the first, second, and fourth lenses are spherical mirror surfaces.

[0085] The optical lens according to the above embodiments of this application may employ multiple lenses, such as the nine 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 nine lenses have been described as an example in the embodiments, the optical lens is not limited to including nine lenses. If necessary, 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.

[0086] Example 1

[0087] 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.

[0088] 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, an eighth lens L8, and a ninth lens L9.

[0089] The first lens L1 has positive optical power, and its object side S1 is convex, and its image side S2 is convex.

[0090] The second lens L2 has negative optical power, and its object side S2 is concave, while its image side S3 is concave.

[0091] The third lens L3 has positive optical power, and its object side S4 is convex, while its image side S5 is convex.

[0092] The fourth lens L4 has positive optical power, with its object side S6 being concave and its image side S7 being convex.

[0093] The fifth lens L5 has negative optical power, and its object side S8 is concave, as is its image side S9.

[0094] The sixth lens L6 has positive optical power, with its object side S10 being concave and its image side S11 being convex.

[0095] The seventh lens L7 has positive optical power, with its object side S12 being concave and its image side S13 being convex.

[0096] The eighth lens L8 has negative optical power, and its object side S14 is concave, and its image side S15 is concave.

[0097] The ninth lens L9 has negative optical power, and its object side S16 is concave, and its image side S17 is concave.

[0098] The first lens L1 and the second lens L2 form a cemented lens.

[0099] The optical lens may also include an aperture stop STO, which may be set between the fourth lens L4 and the fifth lens L5. More specifically, the aperture stop STO may be set on the image side S7 of the fourth lens L4.

[0100] Optionally, the optical lens may also include a filter (not shown) having an object-side side and an image-side side and / or a protective glass CG having an object-side side S18 and an image-side side S19. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensor chip located at the imaging surface IMA. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the imaging surface IMA.

[0101] 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).

[0102]

[0103]

[0104] Table 1

[0105] In this embodiment and the following embodiments, the optical lens according to this application can be adapted to different object distances by changing the distance on the optical axis between the image-side surface of the fourth lens and the object-side surface of the fifth lens, thereby broadening the application scenarios of the optical lens. For example, as the object distance increases, the distance on the optical axis between the image-side surface of the fourth lens and the object-side surface of the fifth lens can be decreased for adaptation. As an example, an optical lens that meets the parameters in Table 1 can be applied to a scenario with an object distance of 0.75m. In an exemplary embodiment, the distance on the optical axis between the image-side surface of the fourth lens and the object-side surface of the fifth lens can be changed within the range of 0mm to 0.8mm, enabling the optical lens to achieve clear imaging within the range of object distances from 0.3m to infinity.

[0106] Table 2 shows the distance T45 along the optical axis between the image side of the fourth lens and the object side of the fifth lens when the object distances are infinity, 0.75m, and 0.3m. The object distance is in meters (m), and T45 is in millimeters (mm). It should be noted that Table 2 only illustrates the object distances at infinity, 0.75m, and 0.3m. However, this application is not limited to these cases. By changing the value of T45 within the range of object distances from 0.3m to infinity, clear imaging can be achieved at different object distances. Furthermore, changing the value of T45 can correct the infrared defocus, which is beneficial for achieving clear infrared focusing.

[0107] Object distance 0.3 0.75 Infinity T45 0.71 0.33 0.10

[0108] Table 2

[0109] In Example 1, the object-side and image-side surfaces of each of the first, second, and fourth lenses are spherical mirrors. The object-side and image-side surfaces of any one of the third, fifth, sixth, seventh, eighth, and ninth lenses are aspherical. The surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0110]

[0111] 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 3 gives the higher-order coefficients A4, A6, A8, A1, A2, A3, A4, A5, A6, A8, A9, A1 ... 10 A 12 A 14 and A 16 .

[0112]

[0113]

[0114] Table 3

[0115] Example 2

[0116] 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.

[0117] 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, an eighth lens L8, and a ninth lens L9.

[0118] The first lens L1 has positive optical power, and its object side S1 is convex, and its image side S2 is convex.

[0119] The second lens L2 has negative optical power, and its object side S2 is concave, while its image side S3 is concave.

[0120] The third lens L3 has positive optical power, and its object side S4 is convex, while its image side S5 is convex.

[0121] The fourth lens L4 has positive optical power, with its object side S6 being concave and its image side S7 being convex.

[0122] The fifth lens L5 has negative optical power, and its object side S8 is concave, as is its image side S9.

[0123] The sixth lens L6 has positive optical power, with its object side S10 being concave and its image side S11 being convex.

[0124] The seventh lens L7 has positive optical power, with its object side S12 being concave and its image side S13 being convex.

[0125] The eighth lens L8 has negative optical power, and its object side S14 is concave, and its image side S15 is concave.

[0126] The ninth lens L9 has negative optical power, and its object side S16 is concave, and its image side S17 is concave.

[0127] The first lens L1 and the second lens L2 form a cemented lens.

[0128] The optical lens may also include an aperture stop STO, which may be set between the fourth lens L4 and the fifth lens L5. More specifically, the aperture stop STO may be set on the image side S7 of the fourth lens L4.

[0129] Optionally, the optical lens may also include a filter (not shown) having an object-side side and an image-side side and / or a protective glass CG having an object-side side S18 and an image-side side S19. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensor chip located at the imaging surface IMA. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the imaging surface IMA.

[0130] Table 4 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 2, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0131]

[0132] Table 4

[0133] An optical lens that meets the parameters in Table 4 can be used in scenarios with an object distance of 0.75m. In an exemplary embodiment, the distance on the optical axis between the image side of the fourth lens and the object side of the fifth lens can be varied from 0mm to 0.8mm, enabling the optical lens to achieve clear imaging in the range of object distance from 0.3m to infinity.

[0134] Table 5 shows the distance T45 along the optical axis between the image side of the fourth lens and the object side of the fifth lens when the object distances are infinity, 0.75m, and 0.3m. The object distance is in meters (m), and T45 is in millimeters (mm). It should be noted that Table 5 only illustrates the object distances at infinity, 0.75m, and 0.3m. However, this application is not limited to these cases. By changing the value of T45 within the range of object distances from 0.3m to infinity, clear imaging can be achieved at different object distances. Furthermore, changing the value of T45 can correct the infrared defocus, which is beneficial for achieving clear infrared focusing.

[0135] Object distance 0.3 0.75 Infinity T45 0.72 0.34 0.10

[0136] Table 5

[0137] In Example 2, the object-side and image-side surfaces of each of the first, second, and fourth lenses are spherical mirrors. The object-side and image-side surfaces of any one of the third, fifth, sixth, seventh, eighth, and ninth lenses are aspherical. Table 6 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.

[0138] Face number k A4 A6 A8 A10 A12 A14 A16 S4 -12.26 -6.05E-04 1.24E-05 1.64E-06 -2.44E-07 1.60E-08 -3.35E-10 -1.32E-12 S5 -12.80 -3.40E-04 3.61E-05 6.40E-07 -4.78E-07 5.18E-08 -1.61E-09 -8.38E-12 S8 85.00 -3.90E-03 -3.58E-05 5.70E-05 -1.92E-05 2.69E-06 -7.10E-08 -1.32E-08 S9 20.00 -7.60E-03 -3.20E-04 1.39E-04 -2.45E-05 2.32E-06 -3.10E-08 -3.76E-09 S10 77.58 -4.30E-03 -4.74E-04 2.15E-05 2.10E-05 -4.40E-06 3.31E-07 -3.85E-09 S11 -3.54 -4.00E-03 -4.29E-04 5.52E-05 4.88E-06 -1.24E-06 5.79E-08 3.86E-10 S12 84.80 -6.50E-03 -2.47E-04 5.55E-05 1.17E-06 -2.19E-07 7.99E-09 -1.33E-10 S13 2.45 -0.00455 5.40E-04 -4.99E-05 1.75E-06 2.86E-07 -1.27E-08 -6.13E-11 S14 85.00 -2.80E-04 9.93E-06 -3.50E-05 2.72E-06 -2.37E-08 -5.39E-09 1.02E-10 S15 9.47 4.60E-03 -5.77E-04 3.36E-05 -1.09E-06 1.91E-08 -1.41E-10 -2.30E-12 S16 -15.91 -3.43E-03 1.49E-04 -2.50E-06 3.79E-07 -1.51E-08 6.12E-11 6.08E-13 S17 1.74 -2.88E-03 4.43E-05 1.45E-06 -2.15E-07 8.33E-09 -1.90E-10 1.92E-13

[0139] Table 6

[0140] Example 3

[0141] 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.

[0142] 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, an eighth lens L8, and a ninth lens L9.

[0143] The first lens L1 has positive optical power, and its object side S1 is convex, and its image side S2 is convex.

[0144] The second lens L2 has negative optical power, and its object side S2 is concave, while its image side S3 is concave.

[0145] The third lens L3 has positive optical power, and its object side S4 is convex, while its image side S5 is convex.

[0146] The fourth lens L4 has positive optical power, with its object side S6 being concave and its image side S7 being convex.

[0147] The fifth lens L5 has negative optical power, with its object side S8 being concave and its image side S9 being convex.

[0148] The sixth lens L6 has positive optical power, with its object side S10 being concave and its image side S11 being convex.

[0149] The seventh lens L7 has positive optical power, with its object side S12 being concave and its image side S13 being convex.

[0150] The eighth lens L8 has negative optical power, and its object side S14 is concave, and its image side S15 is concave.

[0151] The ninth lens L9 has negative optical power, and its object side S16 is concave, and its image side S17 is concave.

[0152] The first lens L1 and the second lens L2 form a cemented lens.

[0153] The optical lens may also include an aperture stop STO, which may be set between the fourth lens L4 and the fifth lens L5. More specifically, the aperture stop STO may be set on the image side S7 of the fourth lens L4.

[0154] Optionally, the optical lens may also include a filter (not shown) having an object-side side and an image-side side and / or a protective glass CG having an object-side side S18 and an image-side side S19. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensor chip located at the imaging surface IMA. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the imaging surface IMA.

[0155] Table 7 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).

[0156]

[0157] Table 7

[0158] An optical lens that meets the parameters in Table 7 can be used in scenarios with an object distance of 0.75m. In an exemplary embodiment, the distance on the optical axis between the image side of the fourth lens and the object side of the fifth lens can be varied from 0mm to 0.8mm, enabling the optical lens to achieve clear imaging in the range of object distance from 0.3m to infinity.

[0159] Table 8 shows the distance T45 along the optical axis between the image side of the fourth lens and the object side of the fifth lens when the object distances are infinity, 0.75m, and 0.3m. The object distance is in meters (m), and T45 is in millimeters (mm). It should be noted that Table 8 only illustrates the object distances at infinity, 0.75m, and 0.3m. However, this application is not limited to these cases. By changing the value of T45 within the range of object distances from 0.3m to infinity, clear imaging can be achieved at different object distances. Furthermore, changing the value of T45 can correct the infrared defocus, which is beneficial for achieving clear infrared focusing.

[0160] Object distance 0.3 0.75 Infinity T45 0.63 0.31 0.10

[0161] Table 8

[0162] In Example 3, the object-side and image-side surfaces of each of the first, second, and fourth lenses are spherical mirrors. The object-side and image-side surfaces of any one of the third, fifth, sixth, seventh, eighth, and ninth lenses are aspherical. Table 9 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.

[0163] Face number k A4 A6 A8 A10 A12 S4 -27.50 -5.47E-04 1.90E-05 -6.67E-07 1.53E-08 1.43E-09 S5 -11.45 -3.41E-04 4.67E-05 -3.92E-06 2.56E-07 -2.92E-09 S8 32.61 -2.70E-03 1.58E-04 -4.60E-05 7.96E-06 -1.01E-06 S9 -85.00 -7.52E-03 2.09E-04 -4.45E-05 1.13E-05 -1.98E-06 S10 -35.91 -9.20E-03 -3.44E-04 1.00E-04 -1.44E-05 9.16E-07 S11 29.39 -6.80E-03 -2.21E-04 6.79E-05 -3.45E-06 -6.56E-08 S12 -75.60 -6.10E-03 -7.09E-05 4.45E-06 3.98E-06 -2.11E-07 S13 0.16 -1.86E-03 6.60E-05 -9.02E-06 1.15E-06 -2.78E-08 S14 85.00 -4.94E-04 -9.92E-05 -2.75E-07 4.92E-07 -4.30E-08 S15 -76.98 2.00E-03 -2.56E-04 1.25E-05 -3.59E-07 3.73E-09 S16 -1.09 -8.07E-04 9.95E-06 -1.75E-06 3.79E-07 -1.06E-08 S17 -64.42 -1.40E-03 4.12E-05 -2.18E-06 6.34E-08 -5.13E-10

[0164] Table 9

[0165] Example 4

[0166] 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.

[0167] 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, an eighth lens L8, and a ninth lens L9.

[0168] The first lens L1 has positive optical power, and its object side S1 is convex, and its image side S2 is convex.

[0169] The second lens L2 has negative optical power, and its object side S2 is concave, while its image side S3 is concave.

[0170] The third lens L3 has positive optical power, and its object side S4 is convex, while its image side S5 is convex.

[0171] The fourth lens L4 has positive optical power, with its object side S6 being concave and its image side S7 being convex.

[0172] The fifth lens L5 has negative optical power, and its object side S8 is concave, as is its image side S9.

[0173] The sixth lens L6 has positive optical power, with its object side S10 being concave and its image side S11 being convex.

[0174] The seventh lens L7 has positive optical power, with its object side S12 being concave and its image side S13 being convex.

[0175] The eighth lens L8 has negative optical power, and its object side S14 is concave, and its image side S15 is concave.

[0176] The ninth lens L9 has negative optical power, and its object side S16 is concave, and its image side S17 is concave.

[0177] The first lens L1 and the second lens L2 form a cemented lens.

[0178] The optical lens may also include an aperture stop STO, which may be set between the fourth lens L4 and the fifth lens L5. More specifically, the aperture stop STO may be set on the image side S7 of the fourth lens L4.

[0179] Optionally, the optical lens may also include a filter (not shown) having an object-side side and an image-side side and / or a protective glass CG having an object-side side S18 and an image-side side S19. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensor chip located at the imaging surface IMA. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the imaging surface IMA.

[0180] Table 10 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).

[0181]

[0182] Table 10

[0183] An optical lens that meets the parameters in Table 11 can be used in scenarios with an object distance of 0.75m. In an exemplary embodiment, the distance on the optical axis between the image side of the fourth lens and the object side of the fifth lens can be varied from 0mm to 0.8mm, enabling the optical lens to achieve clear imaging in the range of object distance from 0.3m to infinity.

[0184] Table 11 shows the distance T45 along the optical axis between the image side of the fourth lens and the object side of the fifth lens when the object distances are infinity, 0.75m, and 0.3m. The object distance is in meters (m), and T45 is in millimeters (mm). It should be noted that Table 11 only illustrates the object distances at infinity, 0.75m, and 0.3m. However, this application is not limited to these cases. By changing the value of T45 within the range of object distances from 0.3m to infinity, clear imaging can be achieved at different object distances. Furthermore, changing the value of T45 can correct the infrared defocus, which is beneficial for achieving clear infrared focusing.

[0185] Object distance 0.3 0.75 Infinity T45 0.68 0.33 0.10

[0186] Table 11

[0187] In Example 4, the object-side and image-side surfaces of each of the first, second, and fourth lenses are spherical mirrors. The object-side and image-side surfaces of any one of the third, fifth, sixth, seventh, eighth, and ninth lenses are aspherical. Table 12 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.

[0188] Face number k A4 A6 A8 A10 A12 A14 S4 -20.60 -5.90E-04 1.48E-05 9.00E-07 -1.88E-07 1.47E-08 -3.72E-10 S5 -2.80 -3.69E-04 4.76E-05 -1.80E-06 -1.90E-07 3.68E-08 -1.47E-09 S8 81.06 -3.06E-03 8.44E-05 1.75E-05 1.00E-05 1.57E-06 -1.14E-07 S9 6.85 -7.31E-03 -8.12E-05 5.90E-05 -8.95E-06 3.20E-10 7.72E-08 S10 -62.14 -6.30E-03 -3.51E-04 1.26E-05 1.49E-05 -3.40E-06 2.48E-08 S11 3.73 -4.50E-03 -3.62E-04 5.58E-05 2.21E-06 -7.73E-07 3.62E-08 S12 -85.00 -6.35E-03 -3.40E-04 5.00E-05 2.30E-06 -3.24E-07 6.68E-09 S13 1.27 -3.70E-03 4.07E-04 -3.54E-05 1.03E-06 2.10E-07 -1.00E-08 S14 40.40 -1.50E-03 9.39E-04 -3.12E-05 1.90E-06 -3.30E-08 -1.28E-09 S15 1.45 3.50E-03 -4.26E-04 2.29E-05 -7.01E-07 1.35E-08 -1.90E-10 S16 -6.10 -1.60E-03 5.85E-05 6.80E-07 3.13E-07 -1.83E-08 2.07E-10 S17 -48.03 -1.20E-03 5.00E-06 1.08E-06 -1.09E-07 4.08E-09 -4.82E-11

[0189] Table 12

[0190] In summary, Examples 1 to 4 satisfy the relationships shown in Table 13 below.

[0191]

[0192]

[0193] Table 13

[0194] 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, In an embodiment, the optical lens comprises, in order from the object side to the image side along the optical axis: a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; a fourth lens having positive refractive power; a fifth lens having negative refractive power; a sixth lens having positive refractive power; a seventh lens having positive refractive power; an eighth lens having negative refractive power; and a ninth lens having negative refractive power. The number of lenses with refractive power in the optical lens is nine. The effective focal length F8 of the eighth lens and the effective focal length F of the optical lens satisfy: -7.2≤F8 / F≤-2.

4.

2. The optical lens of claim 1, wherein, The effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: 0.8≤F1 / F≤1.

1.

3. The optical lens of claim 1, wherein, The effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: -2.1≤F2 / F≤-1.

3.

4. The optical lens of claim 1, wherein, The effective focal length F3 of the third lens and the effective focal length F of the optical lens satisfy: 2.5≤F3 / F≤2.

9.

5. The optical lens of claim 1, wherein, The effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy: 12.0≤F4 / F≤14.

5.

6. The optical lens of claim 1, wherein, The effective focal length F5 of the fifth lens and the effective focal length F of the optical lens satisfy: -7≤F5 / F≤-4.

5.

7. The optical lens of claim 1, wherein, The effective focal length F6 of the sixth lens and the effective focal length F of the optical lens satisfy: 2.1≤F6 / F≤6.

4.

8. The optical lens of claim 1, wherein, The effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy: 0.9≤F7 / F≤1.

4.

9. The optical lens of claim 1, wherein, The effective focal length F9 of the ninth lens and the effective focal length F of the optical lens satisfy: -0.7≤F9 / F≤-0.

4.

10. The optical lens of any of claims 1-9, wherein, The maximum light passing full aperture Dmax of the optical lens and the distance TTL from the object side surface of the first lens to the image plane of the optical lens on the optical axis satisfy: 0.4≤Dmax / TTL≤0.

7.

11. The optical lens of any of claims 1-9, wherein, The distance TTL from the object side surface of the first lens to the image plane of the optical lens on the optical axis and the effective focal length F of the optical lens satisfy: 1.4≤TTL / F≤1.

6.

12. The optical lens of any of claims 1-9, wherein, The effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy: 2.1≤F / ENPD≤2.

4.

13. The optical lens of any of claims 1-9, wherein, The half image height H of the optical lens and the effective focal length F of the optical lens satisfy: 0.5≤H / F≤0.

6.

14. The optical lens of any of claims 1-9, wherein, The combined focal length F12 of the first lens and the second lens and the effective focal length F of the optical lens satisfy: 1.6≤F12 / F≤1.

8.

15. The optical lens of any of claims 1-9, wherein, The Abbe number VD2 of the second lens satisfies: 20≤VD2≤30.

16. The optical lens of any of claims 1-9, wherein, The Abbe number VD4 of the fourth lens satisfies: 90≤VD4≤100.

17. The optical lens of any of claims 1-9, wherein, The distance T45 from the image side surface of the fourth lens to the object side surface of the fifth lens on the optical axis satisfies: 0mm≤T45≤0.8mm. The distance T45 from the image side surface of the fourth lens to the object side surface of the fifth lens on the optical axis and the distance TTL from the object side surface of the first lens to the image plane of the optical lens on the optical axis satisfy: 0≤T45 / TTL≤0.

1.

18. The optical lens according to any one of claims 1-9, wherein, the object side surface of the first lens is convex, and the image side surface of the first lens is convex; the object side surface of the second lens is concave, and the image side surface of the second lens is concave; the object side surface of the third lens is convex, and the image side surface of the third lens is convex; the object side surface of the fourth lens is concave, and the image side surface of the fourth lens is convex; the object side surface of the fifth lens is concave; the object side surface of the sixth lens is concave, and the image side surface of the sixth lens is convex; the object side surface of the seventh lens is concave, and the image side surface of the seventh lens is convex; the object side surface of the eighth lens is concave; and the object side surface of the ninth lens is concave, and the image side surface of the ninth lens is concave.

19. The optical lens of claim 1, wherein, the optical lens satisfies at least one of the following conditional expressions: 0.85≤F1 / F≤0.91, -1.68≤F2 / F≤-1.39, 2.56≤F3 / F≤2.61, 12.12≤F4 / F≤12.59, -6.89≤F5 / F≤-4.66, 2.19≤F6 / F≤6.34, 1.12≤F7 / F≤1.31, -7.13≤F8 / F≤-2.44, -0.60≤F9 / F≤-0.53, 0.6≤Dmax / TTL≤0.62, 1.47≤TTL / F≤1.50, 2.15≤F / ENPD≤2.2, 0.50≤H / F≤0.52, 1.65≤F12 / F≤1.69, wherein F is an effective focal length of the optical lens, F1 is an effective focal length of the first lens, F2 is an effective focal length of the second lens, F3 is an effective focal length of the third lens, F4 is an effective focal length of the fourth lens, F5 is an effective focal length of the fifth lens, F6 is an effective focal length of the sixth lens, F7 is an effective focal length of the seventh lens, F8 is an effective focal length of the eighth lens, F9 is an effective focal length of the ninth lens, Dmax is a maximum clear aperture of the optical lens, TTL is a distance from an object side surface of the first lens to an image plane of the optical lens on the optical axis, ENPD is an effective focal length F of the optical lens and an entrance pupil diameter of the optical lens, H is a half image height of the optical lens, and F12 is a combined focal length of the first lens and the second lens.

Images