Optical lens

Abstract

The utility model discloses an optical lens. The optical lens sequentially comprises 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 from an object side to an image side along an optical axis, the first lens has negative focal power, the object side surface is a convex surface, and the image side surface is a concave surface; the second lens has negative focal power, the object side surface of the second lens is a convex surface, and the image side surface is a concave surface; the third lens has negative focal power, and the object side surface of the third lens is a concave surface; the fourth lens has positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface is a convex surface; the object side surface of the fifth lens is a convex surface; the image side surface of the sixth lens is a convex surface; the seventh lens has negative focal power, and the object side surface of the seventh lens is a concave surface; the eighth lens has positive focal power, the object side surface of the eighth lens is a convex surface, and the image side surface is a convex surface; wherein the combined effective focal length Fa of the first to fourth lenses and the total effective focal length F of the optical lens meet the condition that Fa / F is greater than or equal to-4.1 and less than or equal to-2.2.

Description

Technical Field

[0001] This application relates to the field of optical elements, and particularly to an optical lens. Background Art

[0002] With the continuous development of optical lens technology, optical lenses are increasingly widely used. In many fields such as security monitoring, automotive assisted driving, smartphones, intelligent detection, action cameras, video conferencing, and virtual reality, optical lenses play an important role. Therefore, the market's requirements for the imaging quality of optical lenses are also getting higher and higher. At the same time, in order to provide a wider field of view, the market requires optical lenses to have a larger field of view; in order to obtain more light flux, the market requires optical lenses to have a larger aperture; in order to be easy to carry, the market requires optical lenses to have a smaller volume. Therefore, designing an optical lens with at least one of the characteristics of high resolution, large field of view, large aperture, and small volume has become a market development trend. Utility Model Content

[0003] This application provides an optical lens, which sequentially includes 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 along the optical axis from the object side to the image side; the first lens has a negative optical power, its object side is convex, and its image side is concave; the second lens has a negative optical power, its object side is convex, and its image side is concave; the third lens has a negative optical power, its object side is concave; the fourth lens has a positive optical power, its object side is convex, and its image side is convex; the object side of the fifth lens is convex; the image side of the sixth lens is convex; the seventh lens has a negative optical power, its object side is concave; the eighth lens has a positive optical power, its object side is convex, and its image side is convex; wherein, the combined effective focal length Fa of the first lens to the fourth lens and the total effective focal length F of the optical lens satisfy: -4.1 ≤ Fa / F ≤ -2.2.

[0004] According to an exemplary embodiment of the present application, the clear aperture radius D1 of the object side of the first lens and the effective focal length F1 of the first lens satisfy: -0.8 ≤ D1 / F1 ≤ -0.6.

[0005] According to an exemplary embodiment of the present application, the clear aperture radius D2 of the image side of the first lens and the radius of curvature R2 of the image side of the first lens satisfy: 0.8 ≤ D2 / R2 ≤ 1.0.

[0006] According to an exemplary embodiment of the present application, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -7.6 ≤ F1 / F ≤ -4.9.

[0007] According to an exemplary embodiment of the present application, the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: -3.9 ≤ F2 / F ≤ -2.9.

[0008] According to an exemplary embodiment of the present application, the effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy: 2.8 ≤ F4 / F ≤ 3.9.

[0009] According to an exemplary embodiment of the present application, the optical lens further includes a diaphragm located between the fourth lens and the fifth lens, and the distance d4 between the image side surface of the fourth lens and the diaphragm on the optical axis and the total optical length TTL of the optical lens satisfy: 0 ≤ d4 / TTL ≤ 0.1.

[0010] According to an exemplary embodiment of the present application, the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: 0.1 ≤ |F5 / F6| ≤ 4.8.

[0011] According to an exemplary embodiment of the present application, the Abbe number V5 of the fifth lens, the Abbe number V6 of the sixth lens and the total effective focal length F of the optical lens satisfy: 25.2mm -1 ≤ |V5 - V6| / F ≤ 33.4mm -1 。

[0012] According to an exemplary embodiment of the present application, the effective focal length F7 of the seventh lens and the total effective focal length F of the optical lens satisfy: -4.7 ≤ F7 / F ≤ -2.7.

[0013] According to an exemplary embodiment of the present application, the radius of curvature R72 of the image side surface of the seventh lens and the radius of curvature R81 of the object side surface of the eighth lens satisfy: 0.5 ≤ (R72 - R81) / (R72 + R81) ≤ 1.2.

[0014] According to an exemplary embodiment of the present application, the combined effective focal length F12 of the first lens and the second lens and the total effective focal length F of the optical lens satisfy: -2.2 ≤ F12 / F ≤ -1.5.

[0015] According to an exemplary embodiment of the present application, the fifth lens and the sixth lens are glued together to form a glued lens, and the positive and negative attributes of the optical powers of the fifth lens and the sixth lens are opposite.

[0016] According to an exemplary embodiment of the present application, the combined effective focal length Fb of the fifth lens to the eighth lens and the total effective focal length F of the optical lens satisfy: 2.4 ≤ Fb / F ≤ 3.1.

[0017] According to an exemplary embodiment of the present application, the combined effective focal length Fa of the first lens to the fourth lens and the combined effective focal length Fb of the fifth lens to the eighth lens satisfy: -1.3 ≤ Fa / Fb ≤ -0.7.

[0018] According to an exemplary embodiment of the present application, the back focal length BFL of the optical lens and the total length TTL of the optical lens satisfy: 0.1 ≤ BFL / TTL ≤ 0.2.

[0019] According to an exemplary embodiment of the present application, the total length TTL of the optical lens, the maximum semi-image height H of the optical lens, and the maximum semi-field angle DFOV of the optical lens satisfy: 0 < TTL / H / DFOV × 1° ≤ 0.1.

[0020] According to an exemplary embodiment of the present application, the total effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy: 1.2 ≤ F / ENPD ≤ 1.35. Description of the Drawings

[0021] Other features, objects, and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings. Among them:

[0022] Figure 1 Shows a schematic structural diagram of an optical lens according to Embodiment 1 of the present application;

[0023] Figure 2 Shows a schematic structural diagram of an optical lens according to Embodiment 2 of the present application;

[0024] Figure 3 Shows a schematic structural diagram of an optical lens according to Embodiment 3 of the present application;

[0025] Figure 4 Shows a schematic structural diagram of an optical lens according to Embodiment 4 of the present application;

[0026] Figure 5 Shows a schematic structural diagram of an optical lens according to Embodiment 5 of the present application. Detailed Embodiments

[0027] To better understand the present application, various aspects of the present application are described in detail with reference to the drawings. It should be understood that these detailed descriptions are only descriptions of the exemplary embodiments of the present application and do not limit the scope of the present application in any way.

[0028] In the accompanying drawings, for ease of explanation, the thickness, size, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the accompanying drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the accompanying drawings. The accompanying drawings are only examples and are not drawn to an exact scale.

[0029] In this document, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object being photographed is called the object side surface of the lens, and the surface of each lens closest to the image plane is called the image side surface of the lens.

[0030] It should also be understood that the terms "comprising", "including", "having", "containing", and / or "including having", 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. It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features.

[0031] Unless otherwise defined, all terms used herein have the same meaning as the ordinary understanding of those of ordinary skill in the art to which this application belongs. The terms should be interpreted to have a meaning consistent with their meaning in the context of the related art, and will not be interpreted in an idealized or overly formal sense unless explicitly defined as such herein.

[0032] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will detail this application with reference to the accompanying drawings and in combination with the embodiments.

[0033] On the one hand, this application provides an optical lens. The optical lens sequentially includes 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 along the optical axis from the object side to the image side. There can be a spacing distance between any two adjacent lenses among the first lens to the eighth lens.

[0034] 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 can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor element (CMOS).

[0035] In an exemplary embodiment, the first lens has a negative focal power. Its object side is convex and its image side is concave. The first lens having a negative focal power serves to smoothly transition light; the convex object side is conducive to collecting large-angle light from the object side, thereby expanding the field of view angle; the concave image side is conducive to gently emitting light to reduce the incident angle of light on the object side of the second lens, thereby reducing the aberrations related to the field of view and improving the imaging quality.

[0036] In an exemplary embodiment, the second lens has a negative focal power. Its object side is convex and its image side is concave, and it serves to diverge light. It cooperates with the first lens to further reduce the incident angle of light on the object side of the third lens, reduce the off-axis aberrations of the lenses behind it, and is conducive to improving the imaging quality of the optical lens.

[0037] In an exemplary embodiment, the third lens has a negative focal power. Its object side is concave and it serves to diverge light, so that the light transitions smoothly. At the same time, it is conducive to allowing as much large-angle light as possible to enter the lenses behind, thereby improving the illuminance of the optical lens.

[0038] In an exemplary embodiment, the fourth lens has a positive focal power. Its object side is convex and its image side is convex, and it serves to converge light, thereby being able to reduce the incident height of light on the fifth lens, and further being able to reduce the aperture of the lenses behind, which is conducive to miniaturizing the optical lens.

[0039] In an exemplary embodiment, the object side of the fifth lens is convex, which is conducive to receiving the light from the fourth lens and ensuring the smooth transition of light.

[0040] In an exemplary embodiment, the image side of the sixth lens is convex, which is conducive to the smooth incidence of large-angle light onto the image plane and is conducive to improving the illuminance of the optical lens.

[0041] In an exemplary embodiment, the seventh lens has a negative focal power. Its object side is concave and it serves to diverge light, so that the light transitions smoothly. At the same time, it is conducive to allowing as much large-angle light as possible to enter the lenses behind, thereby improving the imaging quality of the optical lens. Further, the seventh lens can adopt an aspherical mirror surface, which is conducive to correcting the astigmatism of the system and improving the system resolution.

[0042] In an exemplary embodiment, the eighth lens has a positive focal power. Its object side is convex and its image side is convex, which is conducive to reducing the chief ray angle to meet the requirements of the CRA (chief ray angle) curve of the photosensitive chip located on the image plane and improving the matching degree with the photosensitive chip.

[0043] In an exemplary embodiment, the fifth lens and the sixth lens can be glued together to form a cemented lens, which not only helps to correct the chromatic aberration of the optical lens, thereby improving the imaging quality of the optical lens, but also can reduce the tolerance sensitivity problems such as tilt and decentration generated during the assembly of the optical lens, which is beneficial to improving the assembly yield of the optical lens. In addition, the fifth lens and the sixth lens being glued together to form a cemented lens can also shorten the overall optical length of the optical lens, make the structure of the optical lens more compact, and is beneficial to realizing the miniaturization of the optical lens.

[0044] In an exemplary embodiment, the fifth lens and the sixth lens are glued together to form a cemented lens, and the positive and negative attributes of the optical powers of the fifth lens and the sixth lens are opposite.

[0045] In an exemplary embodiment, at least one plastic lens and at least one glass lens may be included among the first lens to the eighth lens. The hybrid assembly of glass lenses and plastic lenses not only helps to balance the imaging performance of the optical lens at different temperatures, so that the optical lens does not defocus in a relatively wide temperature range of -40°C to +80°C and still maintains a high imaging quality under harsh climate conditions, but also helps to reduce the cost of the optical lens. Exemplarily, among the first lens to the eighth lens, there are 3 glass lenses and 5 plastic lenses. For example, the first lens, the fifth lens, and the sixth lens are glass lenses; the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are plastic lenses. In an alternative embodiment, whether to specifically use plastic lenses or glass lenses for the first lens to the eighth lens can also be selected according to actual needs.

[0046] In an exemplary embodiment, at least one aspherical lens may be included among the first lens to the eighth lens. The aspherical lens has better curvature radius characteristics, which is beneficial to correcting the aberration of the optical lens and improving the resolving power of the optical lens. Exemplarily, among the first lens to the eighth lens, there are 5 aspherical lenses. For example, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses, and the other lenses are spherical lenses.

[0047] In an exemplary embodiment, at least one of the first lens to the eighth lens may use an anomalous dispersion glass. The anomalous dispersion glass is beneficial to balancing the chromatic aberration of the optical lens, thereby being beneficial to realizing day and night confocal.

[0048] In an exemplary embodiment, the optical lens may further include a diaphragm, and the diaphragm may be disposed between the fourth lens and the fifth lens. It should be noted that the position of the diaphragm disclosed here is only an example and not a limitation. In an alternative embodiment, the diaphragm may also be disposed at other positions according to actual needs.

[0049] In an exemplary embodiment, the optical lens may further include a protective glass located between the image side of the eighth lens and the image plane. The protective glass can prevent damage to the image-side elements (e.g., chips) of the optical lens. Light from an object sequentially passes through the first lens to the eighth lens and the protective glass and finally forms an image on the image plane.

[0050] In an exemplary embodiment, the optical lens may further include a filter disposed between the image side of the eighth lens and the image plane. The filter can filter light rays with different wavelengths.

[0051] In an exemplary embodiment, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -7.6 ≤ F1 / F ≤ -4.9. By reasonably configuring the effective focal length of the first lens, the light can be effectively and smoothly transitioned. Not only is the object-side field angle effectively enlarged, but also the aberrations related to the field are effectively reduced, thereby effectively improving the imaging quality of the optical lens. Preferably, -7 ≤ F1 / F ≤ -5.4.

[0052] In an exemplary embodiment, the clear aperture semi-diameter D1 of the object side of the first lens and the effective focal length F1 of the first lens satisfy: -0.8 ≤ D1 / F1 ≤ -0.6. By reasonably configuring the effective focal length of the first lens and the clear aperture semi-diameter of its object side, it is beneficial to increase the light angle entering the optical lens, enabling large-angle light to enter the optical lens, which is conducive to increasing the field angle of the optical lens. The full field angle FOV of the optical lens can reach 180°.

[0053] In an exemplary embodiment, the clear aperture semi-diameter D2 of the image side of the first lens and the radius of curvature R2 of the image side of the first lens satisfy: 0.8 ≤ D2 / R2 ≤ 1.0. By reasonably configuring the clear aperture semi-diameter and the radius of curvature of the image side of the first lens, the sagitta height of the image side of the first lens can be reduced, which is beneficial to reducing the processing difficulty of the first lens.

[0054] In an exemplary embodiment, the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: -3.9 ≤ F2 / F ≤ -2.9. By reasonably configuring the effective focal length of the second lens, it can cooperate with the first lens to effectively and smoothly transition the light. Not only is the object-side field angle effectively enlarged, but also the aberrations related to the field are effectively reduced, thereby effectively improving the imaging quality of the optical lens. Preferably, -3.6 ≤ F2 / F ≤ -3.2.

[0055] In an exemplary embodiment, the combined effective focal length F12 of the first lens and the second lens and the total effective focal length F of the optical lens satisfy: -2.2 ≤ F12 / F ≤ -1.5. By reasonably configuring the combined effective focal length of the first lens and the second lens, it is beneficial to make more light enter the optical lens smoothly, control the light trend in the optical lens, and thus is beneficial to improving the resolution of the optical lens. Preferably, -2.1 ≤ F12 / F ≤ -1.7.

[0056] In an exemplary embodiment, the effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy: 2.8 ≤ F4 / F ≤ 3.9. By reasonably configuring the effective focal length of the fourth lens, the ability of the fourth lens to converge light is controlled, thereby effectively reducing the incident height of light on the fifth lens, and further effectively reducing the aperture of the rear lens, which is beneficial to realizing the miniaturization of the optical lens. Preferably, 3.1 ≤ F4 / F ≤ 3.6.

[0057] In an exemplary embodiment, the optical lens further includes a diaphragm located between the fourth lens and the fifth lens. The distance d4 between the image side of the fourth lens and the diaphragm on the optical axis and the total optical length TTL of the optical lens satisfy: 0 ≤ d4 / TTL ≤ 0.1. In this application, the total optical length TTL of the optical lens refers to the distance in the optical axis direction from the object side of the first lens to the image plane of the optical lens. By reasonably configuring the distance between the image side of the fourth lens and the diaphragm on the optical axis, the light near the diaphragm is smoothly transitioned, which is beneficial to improving the resolution of the optical lens.

[0058] In an exemplary embodiment, the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: 0.1 ≤ |F5 / F6| ≤ 4.8. By reasonably configuring the effective focal lengths of the fifth lens and the sixth lens, the effective focal length of the fifth lens is close to that of the sixth lens, which is beneficial to the smooth transition of light, and thus is beneficial to correcting the chromatic aberration of the optical lens and improving the imaging quality of the optical lens.

[0059] In an exemplary embodiment, the Abbe number V5 of the fifth lens, the Abbe number V6 of the sixth lens and the total effective focal length F of the optical lens satisfy: 25.2mm -1 ≤ |V5 - V6| / F ≤ 33.4mm -1 . By reasonably configuring the Abbe numbers of the fifth lens and the sixth lens, it is beneficial to balance the chromatic aberration of the optical lens, and thus is beneficial to realizing day and night confocal. Preferably, 28mm -1 ≤ |V5 - V6| / F ≤ 30.5mm -1 .

[0060] In an exemplary embodiment, the radius of curvature R72 of the image-side surface of the seventh lens and the radius of curvature R81 of the object-side surface of the eighth lens satisfy: 0.5 ≤ (R72 - R81) / (R72 + R81) ≤ 1.2. By reasonably configuring the radius of curvature of the image-side surface of the seventh lens and the object-side surface of the eighth lens, the deviation of the incident angle and the exit angle of light rays in different fields of view can be reduced, enabling the light rays to transition smoothly, thereby reducing the tolerance sensitivity of the optical lens and facilitating the improvement of the assembly yield of the optical lens.

[0061] In an exemplary embodiment, the effective focal length F7 of the seventh lens and the total effective focal length F of the optical lens satisfy: -4.7 ≤ F7 / F ≤ -2.7. By reasonably configuring the effective focal length of the seventh lens, it is beneficial for the light rays exiting the sixth lens to enter the rear lens more smoothly, and at the same time, it can well compensate the eighth lens, thereby achieving the compensation of aberrations. Preferably, -4.3 ≤ F7 / F ≤ -2.9.

[0062] In an exemplary embodiment, the aperture stop can be disposed between the fourth lens and the fifth lens, and the combined effective focal length Fa of the first lens to the fourth lens is less than zero. For example, the combined effective focal length Fa of the first lens to the fourth lens and the total effective focal length F of the optical lens satisfy: -4.1 ≤ Fa / F ≤ -2.2. By reasonably configuring the combined effective focal length of the first lens to the fourth lens, it is beneficial to control the trend of light rays in the optical lens, making the light rays transition more smoothly, thereby reducing the sensitivity of the optical lens and improving the imaging quality of the optical lens. Preferably, -3.8 ≤ Fa / F ≤ -2.3.

[0063] In an exemplary embodiment, the aperture stop can be disposed between the fourth lens and the fifth lens, and the combined effective focal length Fb of the fifth lens to the eighth lens is greater than zero. For example, the combined effective focal length Fb of the fifth lens to the eighth lens and the total effective focal length F of the optical lens satisfy: 2.4 ≤ Fb / F ≤ 3.1. By reasonably configuring the combined effective focal length of the fifth lens to the eighth lens, it is beneficial to control the trend of light rays in the optical lens, making the light rays transition more smoothly, thereby reducing the sensitivity of the optical lens and improving the imaging quality of the optical lens. Preferably, 2.6 ≤ Fb / F ≤ 2.9.

[0064] In an exemplary embodiment, the aperture stop may be disposed between the fourth lens and the fifth lens, and the combined effective focal length Fa of the first lens to the fourth lens and the combined effective focal length Fb of the fifth lens to the eighth lens satisfy: -1.3 ≤ Fa / Fb ≤ -0.7. By reasonably distributing the positive and negative optical powers of the front group of lenses composed of the first lens to the fourth lens and the rear group of lenses composed of the fifth lens to the eighth lens, the combined effective focal lengths of the front group of lenses and the rear group of lenses are relatively close, which is beneficial to controlling the trend of light rays in the optical lens, making the light rays transition more smoothly, reducing the sensitivity of the optical lens, and improving the imaging quality of the optical lens.

[0065] In an exemplary embodiment, the back focal length BFL of the optical lens and the total length TTL of the optical lens satisfy: 0.1 ≤ BFL / TTL ≤ 0.2. The back focal length BFL of the optical lens refers to the distance from the image side of the eighth lens to the image plane of the optical lens on the optical axis. By reasonably configuring the back focal length of the optical lens, the optical lens has a relatively long back focal length, reserving installation space for the optical elements between the eighth lens and the image plane, which is convenient for the assembly of the optical lens. For example, the back focal length BFL of the optical lens may satisfy: 2.5 mm ≤ BFL ≤ 3.3 mm.

[0066] In an exemplary embodiment, the total length TTL of the optical lens, the maximum semi-image height H of the optical lens, and the maximum semi-field angle DFOV of the optical lens satisfy: 0 < TTL / H / DFOV × 1° ≤ 0.1. By reasonably configuring the total length, the maximum semi-image height, and the maximum semi-field angle of the optical lens, when the optical lens has a certain imaging surface and image height, the total length of the optical lens can be effectively limited, which is beneficial to the miniaturization of the optical lens.

[0067] In an exemplary embodiment, the total effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy: 1.2 ≤ F / ENPD ≤ 1.35. By reasonably configuring the total effective focal length and the entrance pupil diameter of the optical lens, it is beneficial for the optical lens to achieve a large aperture, allowing more light rays to enter the optical lens, enhancing the overall brightness of the image, and thus improving the imaging quality of the optical lens.

[0068] By reasonably setting the optical power, shape, and related parameters of each lens, the optical lens provided by this application can have at least one of the following characteristics: large field of view (total field of view angle FOV≥180°), high resolution, large aperture, high temperature tolerance (no defocusing within the temperature range of -40°C to +80°C), small volume (TTL≤18.5mm), and can achieve day and night confocal. The large field of view enables the optical lens to capture a larger field of view; the large aperture means that more light can enter the optical lens per unit time, making the image have a higher brightness and being able to clearly image under low light conditions; the small volume is conducive to the miniaturization of the optical lens, facilitating the carrying of the optical lens and its application in different fields.

[0069] Those skilled in the art should understand that without departing from the technical solution claimed in this application, the number of lenses constituting the optical lens can be changed to obtain each result and advantage described in this specification. For example, although the eight-lens example is described in the embodiment, the optical lens is not limited to including eight lenses. If necessary, the optical lens can also include other numbers of lenses.

[0070] The following further describes specific embodiments of the optical lens applicable to the above embodiments with reference to the accompanying drawings.

[0071] Example 1

[0072] The following refers to Figure 1 Describe the optical lens according to Embodiment 1 of this application.

[0073] As Figure 1As shown in the figure, the optical lens sequentially includes 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 from the object side to the image side. Among them, the fifth lens L5 and the sixth lens L6 are glued together to form a cemented lens. The first lens L1 has a negative optical power, its object side S1 is convex, and its image side S2 is concave; the second lens L2 has a negative optical power, its object side S3 is convex, and its image side S4 is concave; the third lens L3 has a negative optical power, its object side S5 is concave, and its image side S6 is concave; the fourth lens L4 has a positive optical power, its object side S7 is convex, and its image side S8 is convex; the fifth lens L5 has a negative optical power, its object side S10 is convex, and its image side S11 is concave; the sixth lens L6 has a positive optical power, its object side S11 is convex, and its image side S12 is convex; the seventh lens L7 has a negative optical power, its object side S13 is concave, and its image side S14 is convex; the eighth lens L8 has a positive optical power, its object side S15 is convex, and its image side S16 is convex. The optical lens further includes a stop STO located between the fourth lens L4 and the fifth lens L5, and a protective glass CG located between the eighth lens L8 and the image plane IMA. The protective glass CG includes an object side S17 and an image side S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the image plane IMA.

[0074] Table 1 shows the basic parameters of each lens in the optical lens of this embodiment. Among them, the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0075]

[0076]

[0077] Table 1

[0078] In this embodiment, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses. The surface profile x of the aspherical lens can be defined by, but not limited to, the following aspherical formula:

[0079]

[0080] Where x is the sagitta of the distance from the vertex of the aspherical surface at the position with a height of h along the optical axis direction of the aspherical surface; c is the paraxial curvature of the aspherical surface, c = 1 / R (that is, 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 correction coefficient of the i-th order of the aspherical surface. Table 2 gives the conic coefficient k, and the higher-order term coefficients A4, A6, A8, A 10 、A 12 、A14 、A 16 。

[0081] Surface number k <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S3 0.20 -1.26E-03 -1.86E-04 5.04E-06 3.56E-08 -7.54E-09 -2.23E-10 0.00E+00 S4 -1.00 1.16E-02 1.35E-03 -5.24E-04 6.49E-05 5.27E-06 -1.43E-06 1.66E-08 S5 -2.07 -1.14E-02 2.84E-03 -3.63E-04 2.78E-05 -4.63E-08 -1.73E-07 1.00E-08 S6 -148.86 -9.37E-03 2.52E-03 -3.31E-04 -3.44E-05 1.13E-05 6.23E-07 -2.18E-07 S7 -7.78 1.84E-02 1.08E-06 6.58E-05 1.50E-05 -4.79E-06 1.41E-06 -5.43E-08 S8 0.00 1.90E-02 3.47E-03 -1.07E-03 5.90E-04 -1.21E-04 1.07E-05 9.74E-07 S13 -8.26 8.89E-03 -3.17E-03 1.39E-04 -1.20E-05 -5.54E-07 1.67E-07 -6.29E-09 S14 -130.01 1.42E-02 2.81E-04 -6.84E-04 7.34E-05 -1.76E-06 -8.64E-08 6.98E-10 S15 -6.89 3.80E-04 2.16E-03 -4.07E-04 4.31E-05 -2.06E-06 2.03E-08 1.41E-09 S16 -0.62 1.42E-02 2.81E-04 -6.84E-04 7.34E-05 -1.76E-06 -8.64E-08 6.98E-10

[0082] Table 2

[0083] Example 2

[0084] The following refers to Figure 2 the optical lens according to Embodiment 2 of the present application for description.

[0085] As Figure 2 shown, the optical lens sequentially includes 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 from the object side to the image side. Among them, the fifth lens L5 and the sixth lens L6 are cemented to form a cemented lens. The first lens L1 has a negative optical power, its object side surface S1 is convex, and its image side surface S2 is concave; the second lens L2 has a negative optical power, its object side surface S3 is convex, and its image side surface S4 is concave; the third lens L3 has a negative optical power, its object side surface S5 is concave, and its image side surface S6 is concave; the fourth lens L4 has a positive optical power, its object side surface S7 is convex, and its image side surface S8 is convex; the fifth lens L5 has a negative optical power, its object side surface S10 is convex, and its image side surface S11 is concave; the sixth lens L6 has a positive optical power, its object side surface S11 is convex, and its image side surface S12 is convex; the seventh lens L7 has a negative optical power, its object side surface S13 is concave, and its image side surface S14 is concave; the eighth lens L8 has a positive optical power, its object side surface S15 is convex, and its image side surface S16 is convex. The optical lens further includes a stop STO located between the fourth lens L4 and the fifth lens L5, and a protective glass CG located between the eighth lens L8 and the image plane IMA. The protective glass CG includes an object side surface S17 and an image side surface S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the image plane IMA.

[0086] Table 3 shows the basic parameters of each lens in the optical lens of this embodiment. Among them, the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0087] Surface number Surface type Radius of curvature Thickness / Distance Refractive index Abbe number S1 Spherical surface 13.300 0.69 1.76 52.3 S2 Spherical surface 4.630 1.17 S3 Aspherical surface 4.710 0.80 1.54 56.0 S4 Aspherical surface 1.583 2.94 S5 Aspherical surface -2.901 0.66 1.54 56.0 S6 Aspherical surface 14.018 0.07 S7 Aspherical surface 3.876 1.42 1.64 23.5 S8 Aspherical surface -10.589 0.41 STO Spherical surface Infinity -0.01 S10 Spherical surface 4.683 1.00 1.81 25.5 S11 Spherical surface 2.966 2.89 1.59 68.6 S12 Spherical surface -3.168 0.07 S13 Aspherical surface -4.339 0.65 1.67 19.3 S14 Aspherical surface 53.201 0.15 S15 Aspherical surface 3.646 2.06 1.54 56.0 S16 Aspherical surface -5.004 0.77 S17 Spherical surface Infinity 0.71 1.52 64.2 S18 Spherical surface Infinity 1.47 IMA Spherical surface Infinity - - -

[0088] Table 3

[0089] In this embodiment, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses.

[0090] Table 4 gives the conic coefficients k of the aspherical mirror surfaces S3 - S8, S13 - S16 that can be used in this embodiment, as well as the higher-order term coefficients A4, A6, A8, A10 , A 12 , A 14 , A 16 .

[0091] Surface number k <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S3 0.17 -1.46E-03 -1.89E-04 5.21E-06 3.59E-08 -8.25E-09 -2.74E-10 5.25E-12 S4 -1.03 9.55E-03 1.27E-03 -5.63E-04 5.98E-05 4.80E-06 -1.47E-06 1.96E-08 S5 -2.54 -1.08E-02 2.80E-03 -3.72E-04 2.72E-05 9.37E-08 -1.77E-07 5.67E-09 S6 -14.44 -1.01E-02 2.61E-03 -3.18E-04 -3.42E-05 1.09E-05 5.28E-07 -2.35E-07 S7 -6.94 1.84E-02 -9.39E-06 8.59E-05 2.04E-05 -4.34E-06 1.70E-06 -1.35E-07 S8 0.00 1.95E-02 3.60E-03 -1.02E-03 6.02E-04 -1.18E-04 1.11E-05 1.59E-06 S13 -10.10 8.63E-03 -3.34E-03 1.12E-04 -1.48E-05 -7.46E-07 1.23E-07 -4.21E-08 S14 -150.00 1.41E-02 4.04E-04 -7.38E-04 6.59E-05 -1.22E-06 -2.57E-08 -2.88E-09 S15 0.00 -2.44E-04 2.40E-03 -3.89E-04 4.50E-05 -2.38E-06 1.20E-08 7.44E-09 S16 -0.15 -1.07E-03 7.66E-04 -3.15E-05 3.31E-05 -1.32E-06 1.01E-07 1.14E-08

[0092] Table 4

[0093] Example 3

[0094] The following refers to Figure 3 Describe the optical lens according to Embodiment 3 of the present application.

[0095] As Figure 3 shown, the optical lens sequentially includes 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 from the object side to the image side. Among them, the fifth lens L5 and the sixth lens L6 are glued together to form a cemented lens. The first lens L1 has a negative focal power, its object side S1 is convex, and its image side S2 is concave; the second lens L2 has a negative focal power, its object side S3 is convex, and its image side S4 is concave; the third lens L3 has a negative focal power, its object side S5 is concave, and its image side S6 is concave; the fourth lens L4 has a positive focal power, its object side S7 is convex, and its image side S8 is convex; the fifth lens L5 has a positive focal power, its object side S10 is convex, and its image side S11 is convex; the sixth lens L6 has a negative focal power, its object side S11 is concave, and its image side S12 is convex; the seventh lens L7 has a negative focal power, its object side S13 is concave, and its image side S14 is concave; the eighth lens L8 has a positive focal power, its object side S15 is convex, and its image side S16 is convex. The optical lens further includes a diaphragm STO located between the fourth lens L4 and the fifth lens L5, and a protective glass CG located between the eighth lens L8 and the image plane IMA. The protective glass CG includes an object side S17 and an image side S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the image plane IMA.

[0096] Table 5 shows the basic parameters of each lens in the optical lens of this embodiment. Among them, the unit of the radius of curvature and the thickness / distance is millimeter (mm).

[0097] Surface number Surface type Radius of curvature Thickness / Distance Refractive index Abbe number S1 Spherical surface 11.571 0.65 1.76 52.3 S2 Spherical surface 4.137 1.47 S3 Aspherical surface 4.767 0.80 1.54 56.0 S4 Aspherical surface 1.701 2.71 S5 Aspherical surface -2.946 0.66 1.54 56.0 S6 Aspherical surface 9.305 0.07 S7 Aspherical surface 3.901 1.54 1.64 23.5 S8 Aspherical surface -13.243 0.63 STO Spherical surface Infinity -0.23 S10 Spherical surface 3.243 3.02 1.59 68.6 S11 Spherical surface -2.892 1.06 1.81 25.5 S12 Spherical surface -4.443 0.19 S13 Aspherical surface -4.084 0.65 1.67 19.3 S14 Aspherical surface 37.756 0.06 S15 Aspherical surface 3.080 2.03 1.54 56.0 S16 Aspherical surface -5.359 0.77 S17 Spherical surface Infinity 0.71 1.52 64.2 S18 Spherical surface Infinity 1.47 IMA Spherical surface Infinity - - -

[0098] Table 5

[0099] In this embodiment, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses.

[0100] Table 6 shows the conic coefficients k, as well as the high-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 .

[0101] Surface number k <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S3 0.11 -1.64E-03 -1.96E-04 5.40E-06 6.26E-08 -7.14E-09 -2.26E-10 9.61E-13 S4 -0.92 8.55E-03 1.49E-03 -5.46E-04 6.16E-05 5.09E-06 -1.45E-06 -2.99E-09 S5 -2.12 -1.15E-02 2.76E-03 -3.69E-04 2.80E-05 2.74E-07 -1.28E-07 4.28E-09 S6 -41.72 -1.14E-02 2.37E-03 -3.56E-04 -3.64E-05 1.15E-05 6.63E-07 -1.66E-07 S7 -6.55 1.81E-02 -2.29E-04 2.07E-05 6.93E-06 -6.10E-06 1.68E-06 -9.15E-08 S8 0.00 1.92E-02 3.47E-03 -1.10E-03 5.71E-04 -1.29E-04 8.19E-06 8.73E-07 S13 -16.04 8.08E-03 -3.73E-03 5.42E-05 -1.59E-05 7.67E-07 2.38E-07 -2.99E-07 S14 -150.00 1.43E-02 4.40E-04 -7.35E-04 6.73E-05 -7.64E-07 3.14E-08 -2.17E-08 S15 -8.37 -8.27E-04 2.38E-03 -3.87E-04 4.51E-05 -2.42E-06 8.78E-09 8.86E-09 S16 1.29 -2.80E-03 8.23E-04 -2.81E-05 3.23E-05 -1.47E-06 8.35E-08 9.28E-09

[0102] Table 6

[0103] Example 4

[0104] The following refers to Figure 4 describe the optical lens according to Embodiment 4 of the present application.

[0105] As Figure 4 shown, the optical lens sequentially includes 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 from the object side to the image side. Among them, the fifth lens L5 and the sixth lens L6 are cemented to form a cemented lens. The first lens L1 has a negative optical power, its object side S1 is convex, and its image side S2 is concave; the second lens L2 has a negative optical power, its object side S3 is convex, and its image side S4 is concave; the third lens L3 has a negative optical power, its object side S5 is concave, and its image side S6 is convex; the fourth lens L4 has a positive optical power, its object side S7 is convex, and its image side S8 is convex; the fifth lens L5 has a negative optical power, its object side S10 is convex, and its image side S11 is concave; the sixth lens L6 has a positive optical power, its object side S11 is convex, and its image side S12 is convex; the seventh lens L7 has a negative optical power, its object side S13 is concave, and its image side S14 is convex; the eighth lens L8 has a positive optical power, its object side S15 is convex, and its image side S16 is convex. The optical lens further includes a stop STO located between the fourth lens L4 and the fifth lens L5, and a protective glass CG located between the eighth lens L8 and the image plane IMA. The protective glass CG includes an object side S17 and an image side S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the image plane IMA.

[0106] Table 7 shows the basic parameters of each lens in the optical lens of this embodiment. Among them, the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0107] Surface number Surface type Radius of curvature Thickness / Distance Refractive index Abbe number S1 Spherical surface 13.155 0.65 1.76 52.3 S2 Spherical surface 4.367 1.36 S3 Aspherical surface 4.586 0.80 1.54 56.0 S4 Aspherical surface 1.592 2.84 S5 Aspherical surface -2.621 0.77 1.54 56.0 S6 Aspherical surface -30.001 0.07 S7 Aspherical surface 4.186 1.32 1.64 23.5 S8 Aspherical surface -12.362 0.35 STO Spherical surface Infinity 0.22 S10 Spherical surface 4.958 0.95 1.81 25.5 S11 Spherical surface 3.018 2.93 1.59 68.6 S12 Spherical surface -3.343 0.10 S13 Aspherical surface -3.762 0.65 1.67 19.3 S14 Aspherical surface -76.234 0.14 S15 Aspherical surface 3.656 2.16 1.54 56.0 S16 Aspherical surface -4.889 0.78 S17 Spherical surface Infinity 0.71 1.52 64.2 S18 Spherical surface Infinity 1.456 IMA Spherical surface Infinity - - -

[0108] Table 7

[0109] In this embodiment, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses.

[0110] Table 8 gives the conic coefficients k and the higher-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 that can be used for the aspherical surfaces S3 - S8, S13 - S16 in this embodiment.

[0111]

[0112]

[0113] Table 8

[0114] Example 5

[0115] The following refers to Figure 5 to describe the optical lens according to Embodiment 5 of the present application.

[0116] As Figure 5 shown, the optical lens sequentially includes 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 from the object side to the image side. Among them, the fifth lens L5 and the sixth lens L6 are cemented to form a cemented lens. The first lens L1 has a negative optical power, its object side surface S1 is convex, and its image side surface S2 is concave; the second lens L2 has a negative optical power, its object side surface S3 is convex, and its image side surface S4 is concave; the third lens L3 has a negative optical power, its object side surface S5 is concave, and its image side surface S6 is concave; the fourth lens L4 has a positive optical power, its object side surface S7 is convex, and its image side surface S8 is convex; the fifth lens L5 has a positive optical power, its object side surface S10 is convex, and its image side surface S11 is convex; the sixth lens L6 has a negative optical power, its object side surface S11 is concave, and its image side surface S12 is convex; the seventh lens L7 has a negative optical power, its object side surface S13 is concave, and its image side surface S14 is concave; the eighth lens L8 has a positive optical power, its object side surface S15 is convex, and its image side surface S16 is convex. The optical lens further includes a stop STO located between the fourth lens L4 and the fifth lens L5, and a protective glass CG located between the eighth lens L8 and the image plane IMA. The protective glass CG includes an object side surface S17 and an image side surface S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the image plane IMA.

[0117] Table 9 shows the basic parameters of each lens in the optical lens of this embodiment. Among them, the unit of the radius of curvature and the thickness / distance is millimeter (mm).

[0118] Surface number Surface type Radius of curvature Thickness / Distance Refractive index Abbe number S1 Spherical surface 11.033 0.65 1.76 52.3 S2 Spherical surface 3.920 1.69 S3 Aspherical surface 4.987 0.80 1.54 56.0 S4 Aspherical surface 1.635 2.50 S5 Aspherical surface -4.220 0.70 1.54 56.0 S6 Aspherical surface 6.555 0.07 S7 Aspherical surface 3.684 1.63 1.64 23.5 S8 Aspherical surface -18.426 0.74 STO Spherical surface Infinity -0.34 S10 Spherical surface 3.267 2.82 1.59 68.6 S11 Spherical surface -2.869 1.05 1.81 25.5 S12 Spherical surface -4.315 0.25 S13 Aspherical surface -4.302 0.65 1.66 20.4 S14 Aspherical surface 10.521 0.06 S15 Aspherical surface 2.674 2.05 1.54 56.0 S16 Aspherical surface -5.398 0.77 S17 Spherical surface Infinity 0.71 1.52 64.2 S18 Spherical surface Infinity 1.47 IMA Spherical surface Infinity - - -

[0119] Table 9

[0120] In this embodiment, the second lens, the third lens, the fourth lens, the seventh lens, and the eighth lens are all aspherical lenses.

[0121] Table 10 gives the conic coefficients k and the higher-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 .

[0122] Surface number k <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 > <![CDATA[A 12 > <![CDATA[A 14 > <![CDATA[A 16 > S3 -0.02 -2.04E-03 -2.20E-04 4.03E-06 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S4 -0.88 9.32E-03 1.75E-03 -5.24E-04 5.92E-05 4.10E-06 -1.75E-06 -3.66E-08 S5 -2.37 -1.09E-02 3.06E-03 -3.73E-04 2.06E-05 -1.19E-06 -2.01E-07 6.04E-08 S6 -33.10 -1.19E-02 2.20E-03 -3.79E-04 -3.80E-05 1.21E-05 6.90E-07 -1.91E-07 S7 -6.68 1.79E-02 -3.07E-04 5.60E-06 6.69E-06 -5.50E-06 1.81E-06 -1.35E-07 S8 0.00 1.85E-02 3.41E-03 -1.10E-03 5.71E-04 -1.28E-04 8.25E-06 8.69E-07 S13 -19.16 7.56E-03 -3.90E-03 4.44E-05 -1.10E-05 2.57E-06 4.00E-07 -4.61E-07 S14 -77.52 1.85E-02 3.41E-03 -1.10E-03 5.71E-04 -1.28E-04 8.25E-06 8.69E-07 S15 -7.89 -9.02E-04 2.39E-03 -3.81E-04 4.59E-05 -2.37E-06 8.13E-09 8.56E-09 S16 1.23 -2.66E-03 7.66E-04 -1.98E-05 3.43E-05 -1.17E-06 1.27E-07 1.70E-08

[0123] Table 10

[0124] In summary, the conditional expressions in Embodiments 1 to 5 satisfy the relationships shown in Table 11.

[0125] Conditional expression Example 1 Example 2 Example 3 Example 4 Example 5 D1 / F1 -0.676 -0.668 -0.701 -0.744 -0.711 F1 / F -6.902 -6.843 -5.769 -6.249 -5.441 F2 / F -3.321 -3.429 -3.531 -3.505 -3.210 F12 / F -1.992 -2.024 -1.895 -1.950 -1.713 D2 / R2 0.912 0.884 0.919 0.922 0.922 F4 / F 3.143 3.241 3.178 3.526 3.206 d4 / TTL 0.009 0.023 0.034 0.019 0.040 Fa / F -3.064 -3.076 -2.394 -3.727 -2.408 Fb / F 2.834 2.804 2.706 2.861 2.683 Fa / Fb -0.991 -1.018 -0.760 -1.202 -0.772 |F5 / F6| 3.912 4.329 0.213 3.792 0.198 BFL / TTL 0.163 0.165 0.162 0.161 0.161 <![CDATA[|V5-V6| / F(mm -1 )]]> 30.161 30.330 28.099 30.161 28.008 TTL / H / DFOV×1° 0.075 0.074 0.076 0.075 0.075 (R72 - R81) / (R72 + R81) 1.124 0.872 0.849 1.101 0.595 F7 / F -4.283 -4.181 -3.551 -4.133 -2.947 F / ENPD 1.319 1.320 1.320 1.320 1.319

[0126] Table 11

[0127] The above description is only for the preferred embodiments of the present application and the description of the applied technical principles. Those skilled in the art should understand that the scope of protection involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present application.

Claims

1. An optical lens, characterized in that, It successively includes from the object side to the image side along the optical axis: A first lens with negative optical power, whose object side is convex and image side is concave; A second lens with negative optical power, whose object side is convex and image side is concave; A third lens with negative optical power, whose object side is concave; A fourth lens with positive optical power, whose object side is convex and image side is convex; A fifth lens, whose object side is convex; A sixth lens, whose image side is convex; A seventh lens with negative optical power, whose object side is concave; An eighth lens with positive optical power, whose object side is convex and image side is convex; Wherein, the combined effective focal length Fa of the first lens to the fourth lens and the total effective focal length F of the optical lens satisfy: -4.1 ≤ Fa / F ≤ -2.

2.

2. The optical lens according to claim 1, wherein The clear aperture semi-diameter D1 of the object side of the first lens and the effective focal length F1 of the first lens satisfy: -0.8 ≤ D1 / F1 ≤ -0.

6.

3. The optical lens according to claim 1, wherein The clear aperture semi-diameter D2 of the image side of the first lens and the curvature radius R2 of the image side of the first lens satisfy: 0.8 ≤ D2 / R2 ≤ 1.

0.

4. The optical lens according to claim 1, characterized in that, The effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -7.6 ≤ F1 / F ≤ -4.

9.

5. The optical lens according to claim 1, characterized in that, The effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: -3.9 ≤ F2 / F ≤ -2.

9.

6. The optical lens according to claim 1, wherein The effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy: 2.8 ≤ F4 / F ≤ 3.

9.

7. The optical lens according to claim 1, wherein The optical lens further includes a diaphragm located between the fourth lens and the fifth lens, and the distance d4 on the optical axis between the image side of the fourth lens and the diaphragm and the overall optical length TTL of the optical lens satisfy: 0 ≤ d4 / TTL ≤ 0.

1.

8. The optical lens according to claim 1, characterized in that, The effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: 0.1 ≤ |F5 / F6| ≤ 4.

8.

9. The optical lens according to claim 1, wherein The Abbe number V5 of the fifth lens, the Abbe number V6 of the sixth lens and the total effective focal length F of the optical lens satisfy: 25.2 mm -1 ≤|V5-V6| / F≤33.4mm -1 .

10. The optical lens according to claim 1, characterized in that, The effective focal length F7 of the seventh lens and the total effective focal length F of the optical lens satisfy: -4.7 ≤ F7 / F ≤ -2.

7.

11. The optical lens according to claim 1, wherein, The curvature radius R72 of the image side of the seventh lens and the curvature radius R81 of the object side of the eighth lens satisfy: 0.5 ≤ (R72 - R81) / (R72 + R81) ≤ 1.

2.

12. The optical lens according to any one of claims 1 to 11, characterized in that, The combined effective focal length F12 of the first lens and the second lens and the total effective focal length F of the optical lens satisfy: -2.2 ≤ F12 / F ≤ -1.

5.

13. The optical lens according to any one of claims 1 to 11, characterized in that, The fifth lens and the sixth lens are cemented to form a cemented lens, and the positive and negative attributes of the optical powers of the fifth lens and the sixth lens are opposite.

14. The optical lens according to any one of claims 1 to 11, characterized in that, The combined effective focal length Fb of the fifth lens to the eighth lens and the total effective focal length F of the optical lens satisfy: 2.4 ≤ Fb / F ≤ 3.

1.

15. The optical lens according to any one of claims 1 to 11, characterized in that, The combined effective focal length Fa of the first lens to the fourth lens and the combined effective focal length Fb of the fifth lens to the eighth lens satisfy: -1.3 ≤ Fa / Fb ≤ -0.

7.

16. The optical lens according to any one of claims 1 to 11, characterized in that, The back focal length BFL of the optical lens and the overall optical length TTL of the optical lens satisfy: 0.1 ≤ BFL / TTL ≤ 0.

2.

17. The optical lens according to any one of claims 1 to 11, characterized in that, The total optical length TTL of the optical lens, the maximum semi-image height H of the optical lens, and the maximum semi-field of view angle DFOV of the optical lens satisfy: 0 < TTL / H / DFOV × 1° ≤ 0.

1.

18. The optical lens according to any one of claims 1 to 11, characterized in that, The total effective focal length F of the optical lens and the entrance pupil diameter ENPD of the optical lens satisfy: 1.2 ≤ F / ENPD ≤ 1.35.

Images