CN113741004B

CN113741004B - Optical lens, camera module and electronic equipment

Info

Publication number: CN113741004B
Application number: CN202110934046.0A
Authority: CN
Inventors: 刘彬彬; 邹海荣; 李明
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2021-08-13
Filing date: 2021-08-13
Publication date: 2023-07-04
Anticipated expiration: 2041-08-13
Also published as: CN113741004A

Abstract

The invention discloses an optical lens, an image pickup module and electronic equipment, wherein the optical lens comprises a first lens with negative focal power, wherein the first lens is sequentially arranged from an object side to an image side along an optical axis, and the object side and the image side of the first lens are concave surfaces and convex surfaces; a second lens with positive focal power, wherein the object side surface and the image side surface of the second lens are convex surfaces and concave surfaces; a third lens having positive optical power, the image-side surface of which is convex; a fourth lens element with optical power, wherein the object-side surface and the image-side surface of the fourth lens element are concave and convex; a fifth lens with focal power, wherein the object side surface and the image side surface of the fifth lens are concave surfaces and convex surfaces; a sixth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; a seventh lens with positive focal power, the object side surface of which is a convex surface; the eighth lens with negative focal power has a convex object side surface and a concave image side surface. The optical lens also satisfies the relation: 0.15mm < TTL/(ImgH 2)/f <0.2mm. The optical lens, the camera module and the electronic equipment provided by the embodiment of the invention can meet the shooting requirements of miniaturization and wide view and improve the imaging quality of the electronic equipment.

Description

Optical lens, camera module and electronic equipment

Technical Field

The present invention relates to the field of optical imaging technologies, and in particular, to an optical lens, a camera module, and an electronic device.

Background

Along with the pursuit of miniaturization and wide view of electronic products, the light, thin and miniaturized structural characteristics of the optical lens also gradually become the development trend of the optical lens. In the related art, the design and manufacture of optical lenses of electronic devices such as mobile phones and the like have great problems in the aspects of miniaturization, wide view and the like, and the requirements of miniaturization and wide view of the electronic devices are difficult to meet, so that the imaging quality is not improved.

Disclosure of Invention

The embodiment of the invention discloses an optical lens, a camera module and electronic equipment, which can meet the requirements of miniaturization and wide view of the electronic equipment.

In order to achieve the above object, a first aspect of the present invention discloses an optical lens including 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, which are disposed in order from an object side to an image side along an optical axis;

the first lens element has negative refractive power, wherein an object-side surface of the first lens element is concave at a paraxial region thereof, and an image-side surface of the first lens element is convex at a paraxial region thereof;

the second lens has positive focal power, the object side surface of the second lens is a convex surface at a paraxial region, and the image side surface of the second lens is a concave surface at the paraxial region;

The third lens has positive focal power, and the image side surface of the third lens is a convex surface at a paraxial region;

the fourth lens element has optical power, wherein an object-side surface of the fourth lens element is concave at a paraxial region thereof, and an image-side surface of the fourth lens element is convex at a paraxial region thereof;

the fifth lens element has optical power, wherein an object-side surface of the fifth lens element is concave at a paraxial region thereof, and an image-side surface of the fifth lens element is convex at a paraxial region thereof;

the sixth lens element with negative refractive power has a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region;

the seventh lens has positive focal power, and the object side surface of the seventh lens is a convex surface at a paraxial region;

the eighth lens element has negative refractive power, wherein an object-side surface of the eighth lens element is convex at a paraxial region thereof, and an image-side surface of the eighth lens element is concave at a paraxial region thereof;

the optical lens satisfies the following relation: 0.15mm1< TTL/(ImgH 2)/f <0.2mm;

wherein TTL is a distance from an object side surface of the first lens to an imaging surface of the optical lens on the optical axis, imgH is a radius of a maximum effective imaging circle of the optical lens, and f is an effective focal length of the optical lens.

In the optical lens provided by the embodiment, the first lens with negative focal power is adopted, the object side surface of the first lens is concave at the paraxial region, and the image side surface of the first lens is convex at the paraxial region, so that light rays with a large field of view range can be favorably emitted into the optical lens, the light rays emitted into the optical lens can be converged, the field angle is improved, and the requirement of wide vision is met. The second lens element and the third lens element have positive refractive power, wherein an image-side surface of the second lens element is concave at a paraxial region thereof, and an image-side surface of the third lens element is convex at a paraxial region thereof. Therefore, the second lens and the third lens have stronger positive focal power, which is favorable for converging large-angle light rays injected through the first lens and realizing the effect of delaying the angle of marginal light rays. The fourth lens and the fifth lens have optical power, wherein the shapes of the fourth lens and the fifth lens are respectively in a meniscus shape concave towards the object side, so that the aberration of the optical lens can be effectively corrected, and the imaging quality of the optical lens is improved. The sixth lens has negative focal power, which is beneficial to expanding the field of view range of the optical lens and realizing the design requirement of wide view. The seventh lens has positive focal power, the object side surface of the seventh lens is a convex surface at the paraxial region, the total length of the optical lens can be shortened, aberration can be corrected, meanwhile, the light emergent angle can be pressed, and the miniaturized design of the optical lens and the imaging quality of the optical lens are facilitated. The eighth lens element has negative focal power, the object-side surface of the eighth lens element is convex at the paraxial region, and the image-side surface of the eighth lens element is concave at the paraxial region, so that the optical lens element can be kept low in back, i.e., low in height, and the eighth lens element can be made to have a lower height in the direction perpendicular to the optical axis, so that the optical lens element can ensure back focus while achieving wide viewing, and the edge illuminance of the optical lens element can be improved, so that the optical lens element is not prone to dark angles. Therefore, the optical power and the surface shape of each lens are reasonably configured, so that the optical lens meets the design requirements of miniaturization and wide view, and simultaneously achieves the imaging effect with high quality. In addition, by controlling the ratio of the product of the distance from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis and the effective focal length of the optical lens to the radius of the maximum effective imaging circle of the optical lens, the ratio of the height of the optical lens to the imaging surface can be limited to a smaller range. That is, when the above relation is satisfied, the optical lens can achieve the design requirements of miniaturization and wide view, which is beneficial to improving the imaging quality of the optical lens.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 1< ImgH/f.

When the relation is satisfied, the optical lens can realize the shooting requirement of wide view.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 8< |f8|/|SAG81| <20; wherein f8 is the focal length of the eighth lens, and SAG81 is the maximum sagittal height of the object side surface of the eighth lens.

The optical power of the lens can influence the light deflection capability of the optical lens, so that the light deflection capability of the optical lens can be enhanced by controlling the ratio of the focal length of the eighth lens to the distance between the edge of the optical effective area of the object side surface of the eighth lens and the intersection point of the object side surface of the eighth lens and the optical axis on the optical axis and the plane-shaped bending of the object side surface of the eighth lens. When the above relation is satisfied, the focal length and shape of the eighth lens are reasonably set, so as to minimize chromatic aberration and spherical aberration generated by the first lens L1 to the seventh lens L7, thereby improving the imaging quality of the optical lens. In addition, through reasonable distribution of the focal power of the eighth lens, the convergence of the optical lens on edge light rays can be enhanced, and meanwhile, the size of the optical lens is favorably compressed, so that the requirement of miniaturization of the optical lens is met.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 9< |f8|/|SAG82| <15; where f8 is the focal length of the eighth lens, and SAG82 is the maximum sagittal height of the image side of the eighth lens.

Since the optical power of the lens can affect the light absorption capacity of the optical lens, in order to enhance the light absorption capacity of the optical lens, the light absorption capacity of the optical lens can be enhanced by controlling the ratio of the focal length of the eighth lens to the distance between the edge of the optical effective area of the image side of the eighth lens and the intersection point of the image side of the eighth lens and the optical axis on the optical axis. When the above relation is satisfied, the focal length and shape of the eighth lens are reasonably set, so as to minimize chromatic aberration and spherical aberration generated by the first lens L1 to the seventh lens L7, thereby improving the imaging quality of the optical lens. In addition, through reasonable distribution of the focal power of the eighth lens, the light absorption capacity of the optical lens can be enhanced, and meanwhile, the size of the optical lens can be reduced, so that the requirement of miniaturization of the optical lens is met.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: the ratio of SAG11/SAG82 is <0.5; wherein SAG11 is the maximum sagittal height of the object side surface of the first lens, and SAG82 is the maximum sagittal height of the image side surface of the eighth lens.

When the inflection position of the eighth lens is more prominent than the inflection position of the first lens, that is, when the maximum distance between the point on the image side of the eighth lens and the optical axis is greater than the maximum distance between the point on the object side of the first lens and the optical axis, the first lens and the eighth lens are beneficial to correcting the spherical aberration and the curvature of field generated by the first lens to the seventh lens, so that the focal power configuration of each lens is more uniform. When the relation is satisfied, the focal power of the eighth lens in the direction perpendicular to the optical axis and the thickness of the eighth lens can be reasonably controlled, so that the eighth lens is prevented from being too thin or too thick, the incident angle of light on the image side surface of the eighth lens is reduced, and the sensitivity of the optical lens is reduced.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 1< | (SAG 81|+SAG 82)/CT 8<2; wherein SAG81 is the maximum sagittal height of the object side surface of the eighth lens element, SAG82 is the maximum sagittal height of the image side surface of the eighth lens element, and CT8 is the thickness of the eighth lens element on the optical axis.

Because the eighth lens is provided with a plurality of focal power points, distortion and field curvature generated by the first lens to the seventh lens are corrected, and the focal power configuration of the eighth lens close to the imaging surface is uniform. When the relation is satisfied, the focal power of the eighth lens in the direction perpendicular to the optical axis and the thickness of the eighth lens can be reasonably controlled, so that the eighth lens is prevented from being too thin or too thick, the incident angle of light on the image side surface of the eighth lens is reduced, and the sensitivity of the optical lens is reduced.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 5< |f7/SAG72| <7; where f7 is the focal length of the seventh lens, and SAG72 is the maximum sagittal height of the image side of the seventh lens.

When the relation is satisfied, the focal power and the shape of the seventh lens are reasonably arranged, so that the chromatic aberration and the spherical aberration of the optical lens can be reduced to the maximum extent, and the imaging quality of the optical lens is improved. In addition, the reasonable focal power distribution of the seventh lens can further strengthen the light absorption capacity of the optical lens, and meanwhile, the size of the optical lens is favorably compressed, so that the requirement of miniaturization of the optical lens is met.

As an alternative implementation manner, in an embodiment of the present invention, the optical lens satisfies the following relation: 0< yc82/SD82<0.5; wherein Yc82 is a perpendicular distance between a tangential plane of the image side surface of the eighth lens element at an off-axis position, which is perpendicular to the optical axis, and a tangential point of the image side surface of the eighth lens element, and the optical axis, and SD82 is a maximum effective half-caliber of the image side surface of the eighth lens element.

In a second aspect, the present invention discloses an image capturing module, where the image capturing module includes an image sensor and the optical lens according to the first aspect, and the image sensor is disposed on an image side of the optical lens. The camera module with the optical lens of the first aspect not only can meet the requirements of miniaturization and wide view of the camera module, but also can improve the imaging quality of the camera module.

In a third aspect, the present invention discloses an electronic device, which includes a housing and an image capturing module set according to the second aspect, where the image capturing module set is disposed in the housing. The electronic equipment with the camera module can meet the requirements of miniaturization and wide view of the electronic equipment and can improve the imaging quality of the electronic equipment.

Compared with the prior art, the invention has the beneficial effects that:

according to the optical lens, the camera module and the electronic equipment provided by the embodiment of the invention, the eight lenses with focal power are adopted in the optical lens, meanwhile, the first lens with negative focal power is adopted, the object side surface of the first lens is concave at the paraxial region, and the image side surface of the first lens is convex at the paraxial region, so that light rays with a large field of view range can be favorably emitted into the optical lens, the light rays emitted into the optical lens can be converged, the angle of view is improved, and the wide-view requirement is met. The second lens element and the third lens element have positive refractive power, wherein an image-side surface of the second lens element is concave at a paraxial region thereof, and an image-side surface of the third lens element is convex at a paraxial region thereof. Therefore, the second lens and the third lens have stronger positive focal power, which is favorable for converging large-angle light rays injected through the first lens and realizing the effect of delaying the angle of marginal light rays. The fourth lens and the fifth lens have optical power, wherein the shapes of the fourth lens and the fifth lens are respectively in a meniscus shape concave towards the object side, so that the aberration of the optical lens can be effectively corrected, and the imaging quality of the optical lens is improved. The sixth lens has negative focal power, which is beneficial to expanding the field of view range of the optical lens and realizing the design requirement of wide view. The seventh lens has positive focal power, the object side surface of the seventh lens is a convex surface at the paraxial region, the total length of the optical lens can be shortened, aberration can be corrected, meanwhile, the light emergent angle can be pressed, and the miniaturized design of the optical lens and the imaging quality of the optical lens are facilitated. The eighth lens element has negative focal power, the object-side surface of the eighth lens element is convex at the paraxial region, and the image-side surface of the eighth lens element is concave at the paraxial region, so that the optical lens element can be kept low in back, i.e., low in height, and the eighth lens element can be made to have a lower height in the direction perpendicular to the optical axis, so that the optical lens element can ensure back focus while achieving wide viewing, and the edge illuminance of the optical lens element can be improved, so that the optical lens element is not prone to dark angles. The invention enables the optical lens to realize the design requirements of miniaturization and wide view through reasonably configuring the focal power and the surface shape of each lens, and simultaneously realizes the imaging effect with high quality. In addition, the invention also enables the optical lens to meet the following relation: the ratio of the height of the optical lens to the imaging surface can be limited in a smaller range by 0.15mm < TTL/(ImgH 2)/f <0.2mm, so that the miniaturization design and the wide-viewing design requirement of the optical lens are realized, and the imaging quality is improved. That is, the optical lens provided by the invention can meet the requirements of miniaturization and wide vision of electronic equipment, and improve the imaging quality of the electronic equipment.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an optical lens according to an embodiment of the present invention;

FIG. 2 is a graph of light spherical aberration (mm), astigmatic curve (mm) and distortion (%) of an optical lens according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an optical lens disclosed in a second embodiment of the present invention;

FIG. 4 is a graph of light spherical aberration (mm), astigmatic curve (mm) and distortion (%) of an optical lens according to a second embodiment of the present invention;

FIG. 5 is a schematic diagram of an optical lens according to a third embodiment of the present invention;

FIG. 6 is a graph of light ray spherical aberration (mm), astigmatic curve (mm) and distortion (%) of an optical lens according to a third embodiment of the present invention;

FIG. 7 is a schematic diagram of an optical lens according to a fourth embodiment of the present invention;

FIG. 8 is a graph of light ray spherical aberration (mm), astigmatic curve (mm) and distortion (%) of an optical lens according to a fourth embodiment of the present invention;

FIG. 9 is a schematic structural diagram of an optical lens disclosed in a fifth embodiment of the present invention;

FIG. 10 is a graph of light ray spherical aberration (mm), astigmatic curve (mm) and distortion (%) of an optical lens according to the fifth embodiment of the present invention;

FIG. 11 is a schematic view of a camera module according to the present disclosure;

fig. 12 is a schematic structural view of an electronic device disclosed in the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are only used to better describe the present invention and its embodiments and are not intended to limit the scope of the indicated devices, elements or components to the particular orientations or to configure and operate in the particular orientations.

Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in the present invention will be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, the terms "mounted," "configured," "provided," "connected," and "connected" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; may be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements, or components. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, the terms "first," "second," and the like, are used primarily to distinguish between different devices, elements, or components (the particular species and configurations may be the same or different), and are not used to indicate or imply the relative importance and number of devices, elements, or components indicated. Unless otherwise indicated, the meaning of "a plurality" is two or more.

The technical scheme of the invention will be further described with reference to the examples and the accompanying drawings.

Referring to fig. 1, according to a first aspect of the present invention, an optical lens 100 is disclosed, which 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, which are disposed in order from an object side to an image side along an optical axis O. During imaging, light enters the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 in sequence from the object side of the first lens L1 and finally forms an image on the imaging surface 101 of the optical lens 100. The first lens L1 has negative power, the second lens L2 has positive power, the third lens L3 has positive power, the fourth lens L4 has positive or negative power, the fifth lens L5 has positive or negative power, the sixth lens L6 has negative power, the seventh lens L7 has positive power, and the eighth lens L8 has negative power.

Further, the object-side surface 11 of the first lens element L1 is concave at the paraxial region O, and the image-side surface 12 of the first lens element L1 is convex at the paraxial region O; the object-side surface 21 of the second lens element L2 is convex at a paraxial region O, and the image-side surface 22 of the second lens element L2 is concave at the paraxial region O; the object-side surface 31 of the third lens element L3 is convex or concave at a paraxial region O, and the image-side surface 32 of the third lens element L3 is convex at the paraxial region O; the object-side surface 41 of the fourth lens element L4 is concave at a paraxial region O, and the image-side surface 42 of the fourth lens element L4 is convex at the paraxial region O; the object-side surface 51 of the fifth lens element L5 is concave at a paraxial region O, and the image-side surface 52 of the fifth lens element L5 is convex at the paraxial region O; the object-side surface 61 of the sixth lens element L6 is concave at a paraxial region O, and the image-side surface 62 of the sixth lens element L6 is convex at the paraxial region O; the object-side surface 71 of the seventh lens element L7 is convex at the paraxial region O, and the image-side surface 72 of the seventh lens element L7 is concave at the paraxial region O; the object-side surface 81 of the eighth lens element L8 is convex at the paraxial region O, and the image-side surface 82 of the eighth lens element L8 is concave at the paraxial region O.

The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 may be glass lenses, so that the optical lens 100 has good optical effects and can reduce temperature sensitivity.

Alternatively, the materials of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 may be plastic, so that the optical lens 100 is light and thin and easy to process the complex lens surface.

In some embodiments, one or more aspheric surfaces are included in the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8. It is understood that one aspherical lens can achieve the effect of correcting phase differences of a plurality of spherical lenses. That is, the use of the aspherical lens can correct the phase difference and reduce the number of lenses used, which is advantageous in meeting the miniaturization requirement of the optical lens 100 and improving the imaging quality. The specific number of the aspherical lenses may be set according to practical situations, for example, each of the first lens L1 to the eighth lens L8 is an aspherical lens, or any one of the lenses is an aspherical lens, and the present embodiment is not particularly limited.

In some embodiments, the optical lens 100 further includes a stop 102, and the stop 102 may be an aperture stop 102 and/or a field stop 102, which may be disposed between the image side 22 of the second lens L2 and the object side 31 of the third lens L3 of the optical lens 100. It will be appreciated that in other embodiments, the diaphragm 102 may be disposed between other lenses, for example, between the image side 12 of the first lens element L1 and the object side 21 of the second lens element L2, and the arrangement may be specifically adjusted according to practical situations, and the embodiment is not limited thereto.

In some embodiments, the optical lens 100 further includes a filter 10, and the filter 10 is disposed between the eighth lens L8 and the imaging surface 101 of the optical lens 100. By selecting the infrared filter 10, infrared light can be filtered, imaging quality is improved, and imaging is more in line with the visual experience of human eyes. It is to be understood that the optical filter 10 may be made of an optical glass coating or may be made of a colored glass, and may be specifically selected according to practical needs, and the embodiment is not limited specifically.

In some embodiments, the optical lens 100 satisfies the following relationship: 0.15mm < TTL/(ImgH 2)/f <0.2mm; wherein TTL is a distance from the object side surface 11 of the first lens L1 to the imaging surface 101 of the optical lens 100 on the optical axis O, imgH is a radius of a maximum effective imaging circle of the optical lens 100, and f is an effective focal length of the optical lens 100. By controlling the ratio of the product of the distance from the object side surface 11 of the first lens L1 to the imaging surface 101 of the optical lens 100 on the optical axis O and the effective focal length of the optical lens 100 to the radius of the maximum effective imaging circle of the optical lens 100, the ratio of the height of the optical lens 100 to the imaging surface can be limited to a small range. That is, when the above relation is satisfied, the optical lens 100 can achieve a miniaturized design and a wide-viewing design requirement, which is beneficial to improving the imaging quality of the optical lens.

In some embodiments, the optical lens 100 satisfies the following relationship: 1< ImgH/f. When the above relation is satisfied, the optical lens 100 can realize a wide-view photographing requirement. When ImgH/f is more than or equal to 1, the optical lens cannot meet the requirement of wide view, and the shooting requirement of a user on the optical lens 100 is not met.

In some embodiments, the optical lens 100 satisfies the following relationship: 8< |f8|/|SAG81| <20; where f8 is the focal length of the eighth lens element L8, SAG81 is the maximum sagittal height of the object-side surface 81 of the eighth lens element L8. The sagittal height of the object side surface 81 of the eighth lens element L8 is a distance between a point on the object side surface 81 of the eighth lens element L8 and an intersection point of the object side surface 81 of the eighth lens element L8 and the optical axis O along a direction parallel to the optical axis O; when the value of the sagittal height is positive, in the direction parallel to the optical axis O, the point is closer to the image side of the optical lens 100 than at the center of the object side 81 of the eighth lens L8; when the value of the sagittal height is negative, in the direction parallel to the optical axis O, the point is closer to the object side of the optical lens 100 than at the center of the object side 81 of the eighth lens L8.

It can be understood that, since the optical power of the lens can affect the light deflection capability of the optical lens assembly, the light deflection capability of the optical lens assembly 100 can be enhanced by controlling the ratio of the focal length of the eighth lens element L8 to the distance between the intersection point of the object side surface 81 of the eighth lens element L8 and the optical axis O, where the edge of the optically effective area of the object side surface 81 of the eighth lens element L8 is projected onto the optical axis O, the surface-shaped curvature of the object side surface 81 of the eighth lens element L8. When the above relation is satisfied, the focal length and shape of the eighth lens L8 are set reasonably, so as to minimize chromatic aberration and spherical aberration generated by the first lens L1 to the seventh lens L7, thereby improving the imaging quality of the optical lens 100. In addition, by reasonably distributing the focal power of the eighth lens L8, the convergence of the optical lens 100 to the edge light can be enhanced, and the size of the optical lens 100 can be reduced, thereby realizing the miniaturization requirement of the optical lens 100. When |f8|/SAG81 is more than or equal to 20, the focal power of the eighth lens L8 is insufficient, so that the chromatic aberration and spherical aberration correction capability of the optical lens 100 are insufficient, and the imaging quality of the optical lens 100 cannot be ensured; when |f8|/SAG81 is less than or equal to 8, the sagittal height of the object-side surface 81 of the eighth lens L8 is too large, so that the surface shape of the eighth lens L8 is too complex, and the difficulty in molding and processing the eighth lens L8 is increased.

In some embodiments, the optical lens 100 satisfies the following relationship: 9< |f8|/|SAG82| <15; where f8 is the focal length of the eighth lens L8, SAG82 is the maximum sagittal height of the image-side surface 82 of the eighth lens L8. The sagittal height of the image-side surface 82 of the eighth lens element L8 is a distance between a point on the image-side surface 82 of the eighth lens element L8 and an intersection point of the image-side surface 82 of the eighth lens element L8 and the optical axis O along a direction parallel to the optical axis O; when the value of the sagittal height is a positive value, in the direction parallel to the optical axis O, the point is closer to the image side of the optical lens 100 than at the center of the image side 82 of the eighth lens L8; when the value of the sagittal height is negative, in the direction parallel to the optical axis O, the point is closer to the object side of the optical lens 100 than at the center of the image side 82 of the eighth lens L8.

Since the optical power of the lens can affect the light absorption capacity of the optical lens 100, in order to enhance the light absorption capacity of the optical lens 100, the light absorption capacity of the optical lens 100 can be enhanced by controlling the ratio of the focal length of the eighth lens L8 to the distance between the intersection point of the image side 82 of the eighth lens L8 and the optical axis O, where the edge of the optically effective area of the image side 82 of the eighth lens L8 projects onto the optical axis O. When the above relation is satisfied, the focal length and shape of the eighth lens L8 are set reasonably, so as to minimize chromatic aberration and spherical aberration generated by the first lens L1 to the seventh lens L7, thereby improving the imaging quality of the optical lens. In addition, by reasonably distributing the focal power of the eighth lens L8, the ability of the optical lens 100 to absorb light can be enhanced, and the size of the optical lens 100 can be reduced, thereby meeting the requirement of miniaturization of the optical lens. When |f8|/SAG82 is less than or equal to 9, the focal power of the eighth lens L8 is insufficient, so that the chromatic aberration and spherical aberration correction capability of the optical lens 100 are insufficient, and the imaging quality of the optical lens 100 cannot be ensured; when |f8|/SAG82 is not less than 15, the sagittal height of the image side 82 of the eighth lens L8 is too large, so that the surface shape of the eighth lens L8 is too complex, and the difficulty in molding and processing the eighth lens L8 is increased.

In some embodiments, the optical lens 100 satisfies the following relationship: the ratio of SAG11/SAG82 is <0.5; wherein SAG11 is the maximum sagittal height of the object side surface 11 of the first lens L1, SAG82 is the maximum sagittal height of the image side surface 82 of the eighth lens L8. The sagittal height of the object-side surface 11 of the first lens L1 is a distance between a certain point on the object-side surface 11 of the first lens L1 and an intersection point of the object-side surface 11 of the first lens L1 and the optical axis O along a direction parallel to the optical axis O; when the sagittal value is positive, in a direction parallel to the optical axis O, the point is closer to the image side of the optical lens 100 than at the center of the object side 11 of the first lens L1; when the value of the sagittal height is negative, in the direction parallel to the optical axis O, the point is closer to the object side of the optical lens 100 than at the center of the object side 11 of the first lens L1. Also, the sagittal height of the image side surface 82 of the eighth lens element L8 is similar to that described above, and will not be repeated here.

It is understood that the first lens element L1 and the eighth lens element L8 have a curvature, and when the curvature of the eighth lens element L8 is more prominent than the curvature of the first lens element L1, i.e., when the maximum distance between the point on the image side surface 82 of the eighth lens element L8 and the optical axis is greater than the maximum distance between the point on the object side surface 11 of the first lens element L1 and the optical axis O, it is advantageous to correct the spherical aberration and curvature of field generated by the first lens element L1 to the seventh lens element L7, so that the optical power configuration of each lens element is more uniform. When the above relation is satisfied, the focal power of the eighth lens element L8 in the direction perpendicular to the optical axis O and the thickness of the eighth lens element L8 can be reasonably controlled, so as to avoid the eighth lens element L8 being too thin or too thick, thereby reducing the incident angle of the light beam on the image-side surface 82 of the eighth lens element L8 and reducing the sensitivity of the optical lens 100.

In some embodiments, optical lens 100 satisfies the following relationship 1< (|SAG81|+SAG82)/CT 8<2; wherein SAG81 is the maximum sagittal height of the object side surface 81 of the eighth lens element L8, SAG82 is the maximum sagittal height of the image side surface 82 of the eighth lens element L8, and CT8 is the thickness of the eighth lens element L8 on the optical axis O. The sagittal height of the object side surface 81 of the eighth lens element L8 is a distance between a point on the object side surface 81 of the eighth lens element L8 and an intersection point of the object side surface 81 of the eighth lens element L8 and the optical axis O along a direction parallel to the optical axis O; when the value of the sagittal height is positive, in the direction parallel to the optical axis O, the point is closer to the image side of the optical lens 100 than at the center of the object side 81 of the eighth lens L8; when the value of the sagittal height is negative, in the direction parallel to the optical axis O, the point is closer to the object side of the optical lens 100 than at the center of the object side 81 of the eighth lens L8. Also, the sagittal height of the image side surface 82 of the eighth lens element L8 is similar to that described above, and will not be repeated here.

Because the eighth lens L8 is provided with a plurality of focal power points, distortion and curvature of field generated by the first lens L1 to the seventh lens L7 can be corrected, so that the focal power configuration of the eighth lens L8 near the imaging surface 82 is relatively uniform. When the above relation is satisfied, the focal power of the eighth lens L8 in the direction perpendicular to the optical axis O and the thickness of the eighth lens L8 can be reasonably controlled, so as to avoid the eighth lens L8 being too thin or too thick, thereby reducing the incident angle of the light beam on the image-side surface 82 of the eighth lens L8 and reducing the sensitivity of the optical lens. When (|SAG81|+SAG82)/CT 8 is less than or equal to 1, the thickness of the eighth lens L8 is too thick, the incident angle of light on the image side surface 82 of the eighth lens L8 is large, and the sensitivity of the optical lens 100 is large; when (|SAG81|+SAG82)/CT 8 is not less than 2, the optical power of the eighth lens L8 is insufficient, resulting in insufficient distortion and field curvature correction capability of the optical lens 100, affecting the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship: 5< |f7/SAG72| <7; where f7 is the focal length of the seventh lens L7, SAG72 is the maximum sagittal height of the image side 72 of the seventh lens L7. The sagittal height of the image-side surface 72 of the seventh lens L7 is a distance between a point on the image-side surface 72 of the seventh lens L7 and an intersection point of the image-side surface 72 of the seventh lens L7 and the optical axis O along a direction parallel to the optical axis O; when the value of the sagittal height is a positive value, in the direction parallel to the optical axis O, the point is closer to the image side of the optical lens 100 than at the center of the image side 72 of the seventh lens L7; when the value of the sagittal height is negative, in the direction parallel to the optical axis O, the point is closer to the object side of the optical lens 100 than at the center of the image side 72 of the seventh lens L7.

When the above relation is satisfied, the setting of the focal power and the shape of the seventh lens L7 is reasonable, so as to reduce the chromatic aberration and the spherical aberration of the optical lens 100 to the maximum extent and improve the imaging quality of the optical lens 100. In addition, the optical power distribution of the seventh lens L7 can be reasonable, so that the light absorption capability of the optical lens 100 can be further enhanced, and the size of the optical lens 100 can be reduced, thereby realizing the miniaturization requirement of the optical lens. When |f7/SAG 72|is not less than 7, the focal power of the seventh lens L7 is insufficient, so that the chromatic aberration and spherical aberration correction capability of the optical lens 100 are insufficient, and the imaging quality of the optical lens 100 cannot be ensured; when |f7/SAG 72|is less than or equal to 5, the sagittal height of the image side surface 72 of the seventh lens L7 is excessively large, so that the surface shape of the seventh lens L7 is excessively complicated, resulting in an increase in difficulty in molding processing of the seventh lens L7.

In some embodiments, the optical lens 100 satisfies the following relationship: 0< yc82/SD82<0.5; wherein Yc82 is a perpendicular distance between a tangential plane of the image side surface of the eighth lens element at an off-axis position, which is perpendicular to the optical axis, and a tangential point of the image side surface of the eighth lens element, and the optical axis, and SD82 is a maximum effective half-caliber of the image side surface 82 of the eighth lens element L8. Because the eighth lens L8 is provided with a plurality of focal power points, distortion and curvature of field generated by the first lens L1 to the seventh lens L7 can be corrected, so that the focal power configuration of the eighth lens L8 near the imaging surface 101 is relatively uniform. When the above relation is satisfied, the focal power of the eighth lens L8 in the direction perpendicular to the optical axis O and the thickness of the eighth lens L8 can be reasonably controlled, so as to avoid the eighth lens L8 being too thin or too thick, thereby reducing the incident angle of the light beam on the image-side surface 82 of the eighth lens L8 and reducing the sensitivity of the optical lens.

In some embodiments, the optical lens 100 satisfies the following relationship: n1-n8>0.04; where n1 is the refractive index of the first lens L1, and n8 is the refractive index of the eighth lens L8. When the above relation is satisfied, the power distribution of the first lens L1 and the eighth lens L8 is relatively suitable, which is favorable for minimizing chromatic aberration and spherical aberration of the optical lens 100, thereby improving the imaging quality of the optical lens 100. In addition, the optical lens 100 can enhance the light absorption capacity by reasonable focal power distribution while satisfying the above relation, which is beneficial to the realization of the design requirement of miniaturization of the optical lens 100.

The optical lens 100 of the present embodiment will be described in detail below with reference to specific parameters.

Example 1

As shown in fig. 1, a schematic structural diagram of an optical lens 100 according to an embodiment of the present invention is shown, and the optical lens 100 includes a first lens L1, a second lens L2, a stop 102, 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 an optical filter 10 sequentially disposed from an object side to an image side along an optical axis O.

Further, the first lens L1 has negative power, the second lens L2 has positive power, the third lens L3 has positive power, the fourth lens L4 has negative power, the fifth lens L5 has positive power, the sixth lens L6 has negative power, the seventh lens L7 has positive power, and the eighth lens L8 has negative power.

Further, the object-side surface 11 and the image-side surface 12 of the first lens element L1 are concave and convex at the paraxial region O, respectively, and the object-side surface 11 and the image-side surface 12 of the first lens element L1 are convex and concave at the peripheral region O, respectively; the object-side surface 21 and the image-side surface 22 of the second lens element L2 are convex and concave at the paraxial region O, respectively, and the object-side surface 21 and the image-side surface 22 of the second lens element L2 are convex and concave at the peripheral region O, respectively; the object-side surface 31 and the image-side surface 32 of the third lens element L3 are convex and convex at the paraxial region O, respectively, and the object-side surface 31 and the image-side surface 32 of the third lens element L3 are concave and convex at the peripheral region O, respectively; the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are concave and convex at the paraxial region O, respectively, and the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are concave and convex at the peripheral region O, respectively; the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are respectively concave and convex at the paraxial region O, and the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are respectively concave and convex at the peripheral region; the object-side surface 61 and the image-side surface 62 of the sixth lens element L6 are respectively concave and convex at the paraxial region O, and the object-side surface 61 and the image-side surface 62 of the sixth lens element L6 are respectively concave and convex at the peripheral region; the object-side surface 71 and the image-side surface 72 of the seventh lens element L7 are respectively convex and concave at the paraxial region O, and the object-side surface 71 and the image-side surface 72 of the seventh lens element L7 are respectively concave and convex at the peripheral region; the object-side surface 81 and the image-side surface 82 of the eighth lens element L8 are convex and concave at the paraxial region O, respectively, and the object-side surface 81 and the image-side surface 82 of the eighth lens element L8 are convex and convex at the peripheral region.

Specifically, taking the effective focal length f=4.04 mm of the optical lens 100, the aperture value fno=1.87 of the optical lens 100, the field angle fov=101° of the optical lens 100, the total length ttl=6.4 mm of the optical lens 100, and the radius imgh= 4.813mm of the maximum effective imaging circle of the optical lens 100 as examples, other parameters of the optical lens 100 are given in table 1 below. The elements from the object side to the image side are sequentially arranged in the order of the elements from top to bottom in table 1 along the optical axis O of the optical lens 100. In the same lens element, the surface with smaller surface number is the object side surface of the lens element, and the surface with larger surface number is the image side surface of the lens element, i.e., the surface numbers 1 and 2 correspond to the object side surface and the image side surface of the first lens element L1, respectively. The radius Y in table 1 is the radius of curvature of the object side or image side of the corresponding plane number at the optical axis O. The first value in the "thickness" parameter array of the lens is the thickness of the lens on the optical axis O, and the second value is the distance from the image side surface of the lens to the latter surface on the optical axis O. The value of the aperture 102 in the "thickness" parameter row is the distance between the aperture 102 and the object side surface of the third lens L3 on the optical axis O. It is understood that the units of the radius, thickness and focal length of Y in Table 1 are all mm, and the refractive index and Abbe number in Table 1 are obtained at a reference wavelength of 587.6nm, and the focal length is obtained at a reference wavelength of 555 nm.

In the first embodiment, the object side surface and the image side surface of any one of the first lens L1 to the eighth lens L8 are aspheric, and the surface shape x of each aspheric lens can be defined by, but not limited to, the following aspheric formula:

wherein x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at the position with the height h along the optical axis O direction; c is the curvature of the aspherical surface at the optical axis O, c=1/Y (i.e., paraxial curvature c is the inverse of the radius of curvature Y in table 1 above); k is a conic coefficient; ai is the correction coefficient of the i-th order of the aspherical surface. The higher order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors in example one are given in Table 2 below.

TABLE 1

TABLE 2

Referring to fig. 2 (a), fig. 2 (a) shows the optical spherical aberration diagrams of the optical lens 100 of the first embodiment at wavelengths of 470nm, 510nm, 555nm, 610nm and 650 nm. In fig. 2 (a), the abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. As can be seen from fig. 2 (a), the spherical aberration value of the optical lens 100 in the first embodiment is better, which indicates that the imaging quality of the optical lens 100 in the present embodiment is better.

Referring to fig. 2 (B), fig. 2 (B) is a light astigmatism diagram of the optical lens 100 at a wavelength of 555nm in the first embodiment. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatism curves represent the meridional imaging plane 101 curvature T and the sagittal imaging plane 101 curvature S, and it can be seen from fig. 2 (B) that at this wavelength, the astigmatism of the optical lens 100 is well compensated.

Referring to fig. 2 (C), fig. 2 (C) is a graph showing distortion of the optical lens 100 at a wavelength of 555nm in the first embodiment. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from fig. 2 (C), the distortion of the optical lens 100 is well corrected at a wavelength of 555 nm.

Example two

As shown in fig. 3, the optical lens 100 according to the second embodiment of the present invention includes a first lens L1, a second lens L2, a stop 102, 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 an optical filter 10 sequentially disposed from an object side to an image side along an optical axis O.

Further, the object-side surface 11 and the image-side surface 12 of the first lens element L1 are concave and convex at the paraxial region O, respectively, and the object-side surface 11 and the image-side surface 12 of the first lens element L1 are convex and concave at the peripheral region O, respectively; the object-side surface 21 and the image-side surface 22 of the second lens element L2 are convex and concave at the paraxial region O, respectively, and the object-side surface 21 and the image-side surface 22 of the second lens element L2 are convex and concave at the peripheral region O, respectively; the object-side surface 31 and the image-side surface 32 of the third lens element L3 are respectively concave and convex at the paraxial region O, and the object-side surface 31 and the image-side surface 32 of the third lens element L3 are respectively concave and convex at the peripheral region; the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are concave and convex at the paraxial region O, respectively, and the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are concave and convex at the peripheral region O, respectively; the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are respectively concave and convex at the paraxial region O, and the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are respectively concave and convex at the peripheral region; the object-side surface 61 and the image-side surface 62 of the sixth lens element L6 are respectively concave and convex at the paraxial region O, and the object-side surface 61 and the image-side surface 62 of the sixth lens element L6 are respectively concave and convex at the peripheral region; the object-side surface 71 and the image-side surface 72 of the seventh lens element L7 are respectively convex and concave at the paraxial region O, and the object-side surface 71 and the image-side surface 72 of the seventh lens element L7 are respectively concave and convex at the peripheral region; the object-side surface 81 and the image-side surface 82 of the eighth lens element L8 are convex and concave at the paraxial region O, respectively, and the object-side surface 81 and the image-side surface 82 of the eighth lens element L8 are convex and convex at the peripheral region.

Specifically, taking the effective focal length f=4.6 mm of the optical lens 100, the aperture value fno=1.79 of the optical lens 100, the field angle fov=94 of the optical lens 100, the total length ttl=7.3 mm of the optical lens 100, and the radius imgh= 4.813mm of the maximum effective imaging circle of the optical lens 100 as examples, other parameters of the optical lens 100 are given in the following table 3, and the definition of each parameter can be obtained from the description of the foregoing embodiments, which is not repeated herein. It is understood that the units of the radius, thickness and focal length of Y in Table 3 are all mm, and the refractive index and Abbe number in Table 3 are obtained at a reference wavelength of 587.6nm, and the focal length is obtained at a reference wavelength of 555 nm.

In the second embodiment, the object-side surface and the image-side surface of any one of the first lens element L1 to the eighth lens element L8 are aspheric, and the method for calculating the surface shape x of each aspheric lens element can be obtained by the above description of the embodiment, which is not repeated here. The higher order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors in example two are given in Table 4 below.

TABLE 3 Table 3

TABLE 4 Table 4

Referring to fig. 4, as can be seen from the graph of (a) optical spherical aberration in fig. 4, the graph of (B) optical spherical aberration in fig. 4, and the graph of (C) distortion in fig. 4, the longitudinal spherical aberration, astigmatism, and distortion of the optical system 100 are well controlled, so that the optical system 100 of this embodiment has good imaging quality. In addition, regarding the wavelengths corresponding to the curves in fig. 4 (a), fig. 4 (B), and fig. 4 (C), reference may be made to the descriptions in the first embodiment regarding fig. 2 (a), fig. 2 (B), and fig. 2 (C), and the descriptions are omitted here.

Example III

As shown in fig. 5, a schematic structural diagram of an optical lens 100 according to a third embodiment of the present invention, the optical lens 100 includes a first lens L1, a second lens L2, a stop 102, 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 an optical filter 10, which are sequentially disposed from an object side to an image side along an optical axis O.

Further, the first lens L1 has negative power, the second lens L2 has positive power, the third lens L3 has positive power, the fourth lens L4 has negative power, the fifth lens L5 has negative power, the sixth lens L6 has negative power, the seventh lens L7 has positive power, and the eighth lens L8 has negative power.

Specifically, taking the effective focal length f=4.04 mm of the optical lens 100, the aperture value fno=1.87 of the optical lens 100, the field angle fov=100° of the optical lens 100, the total length ttl=6.4 mm of the optical lens 100, and the radius imgh= 4.813mm of the maximum effective imaging circle of the optical lens 100 as examples, other parameters of the optical lens 100 are given in the following table 5, and the definition of each parameter can be obtained from the description of the foregoing embodiments, which is not repeated herein. It is understood that the units of the radius, thickness and focal length of Y in Table 5 are all mm, and the refractive index and Abbe number in Table 5 are obtained at a reference wavelength of 587.6nm, and the focal length is obtained at a reference wavelength of 555 nm.

In the third embodiment, the object-side surface and the image-side surface of any one of the first lens element L1 to the eighth lens element L8 are aspheric, and the method for calculating the surface shape x of each aspheric lens element can be obtained by the above description of the embodiments, which is not repeated here. The higher order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors in example three are given in Table 6 below.

TABLE 5

TABLE 6

Referring to fig. 6, as can be seen from the graph of (a) optical spherical aberration in fig. 6, the graph of (B) optical spherical aberration in fig. 6, and the graph of (C) distortion in fig. 6, the longitudinal spherical aberration, astigmatism, and distortion of the optical system 100 are well controlled, so that the optical system 100 of this embodiment has good imaging quality. In addition, regarding the wavelengths corresponding to the curves in fig. 6 (a), 6 (B) and 6 (C), reference may be made to the descriptions in the first embodiment regarding fig. 2 (a), 2 (B) and 2 (C), and the descriptions are omitted here.

Example IV

As shown in fig. 7, a schematic structural diagram of an optical lens 100 according to a fourth embodiment of the present invention, the optical lens 100 includes a first lens L1, a second lens L2, a stop 102, 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 an optical filter 10, which are sequentially disposed from an object side to an image side along an optical axis O.

Further, the first lens L1 has negative power, the second lens L2 has positive power, the third lens L3 has positive power, the fourth lens L4 has positive power, the fifth lens L5 has negative power, the sixth lens L6 has negative power, the seventh lens L7 has positive power, and the eighth lens L8 has negative power.

Specifically, taking the effective focal length f=4.22 mm of the optical lens 100, the aperture value fno=1.86 of the optical lens 100, the field angle fov=98.6° of the optical lens 100, the total length ttl=6.63 mm of the optical lens 100, and the radius imgh= 4.813mm of the maximum effective imaging circle of the optical lens 100 as examples, other parameters of the optical lens 100 are given in the following table 7, and the definition of each parameter can be obtained from the description of the foregoing embodiments, which is not repeated herein. It is understood that the units of the radius, thickness and focal length of Y in Table 7 are all mm, and the refractive index and Abbe number in Table 7 are obtained at a reference wavelength of 587.6nm, and the focal length is obtained at a reference wavelength of 555 nm.

In the fourth embodiment, the object-side surface and the image-side surface of any one of the first lens element L1 to the eighth lens element L8 are aspheric, and the method for calculating the surface shape x of each aspheric lens element can be obtained by the above description of the embodiments, which is not repeated here. The higher order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors in example four are given in Table 8 below.

TABLE 7

TABLE 8

Referring to fig. 8, as can be seen from the (a) light spherical aberration graph in fig. 8, the (B) light astigmatic graph in fig. 8, and the (C) distortion graph in fig. 8, the longitudinal spherical aberration, astigmatism and distortion of the optical system 100 are well controlled, so that the optical system 100 of the embodiment has good imaging quality. In addition, regarding the wavelengths corresponding to the curves in fig. 8 (a), 8 (B) and 8 (C), reference may be made to the descriptions in the first embodiment regarding fig. 2 (a), 2 (B) and 2 (C), and the descriptions are omitted here.

Example five

As shown in fig. 9, a schematic structural diagram of an optical lens 100 according to a fifth embodiment of the present invention, the optical lens 100 includes a first lens L1, a second lens L2, a stop 102, 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 an optical filter 10, which are sequentially disposed from an object side to an image side along an optical axis O.

Specifically, taking the effective focal length f=3.88 mm of the optical lens 100, the aperture value fno=1.9 of the optical lens 100, the field angle fov=104° of the optical lens 100, the total length ttl=6 mm of the optical lens 100, and the radius imgh= 4.813mm of the maximum effective imaging circle of the optical lens 100 as examples, other parameters of the optical lens 100 are given in the following table 9, and the definition of each parameter can be obtained from the description of the foregoing embodiments, which is not repeated herein. It is understood that the units of the radius, thickness, and focal length of Y in table 9 are all mm, and the refractive index and the dispersion coefficient in table 9 are obtained at a reference wavelength of 587.6nm, and the focal length is obtained at a reference wavelength of 555 nm.

In the fifth embodiment, the object-side surface and the image-side surface of any one of the first lens element L1 to the eighth lens element L8 are aspheric, and the method for calculating the surface shape x of each aspheric lens element can be obtained by using the description of the foregoing embodiments, which is not repeated herein. The following table 10 gives the higher order coefficients A4, A6, A8, a10, a12, a14, a16, a18 and a20 that can be used for each of the aspherical mirrors in embodiment five.

TABLE 9

Table 10

Referring to fig. 10, as can be seen from the graph of (a) optical spherical aberration in fig. 10, the graph of (B) optical spherical aberration in fig. 10, and the graph of (C) distortion in fig. 10, the longitudinal spherical aberration, astigmatism, and distortion of the optical system 100 are well controlled, so that the optical system 100 of this embodiment has good imaging quality. In addition, regarding the wavelengths corresponding to the curves in fig. 10 (a), 10 (B) and 10 (C), reference may be made to the descriptions in fig. 2 (a), 2 (B) and 2 (C) in the first embodiment, and the descriptions are omitted here.

Referring to table 11, table 11 is a summary of the ratios of the relationships in the first to fifth embodiments of the present invention.

TABLE 11

Relation/embodiment	Example 1	Example two	Example III	Example IV	Example five
						0.15mm<TTL/(ImgH*2)/f<0.2mm	0.165mm	0.165mm	0.165mm	0.163mm	0.161mm
1<ImgH/f	1.191	1.046	1.191	1.141	1.240
						8<\|f8\|/\|SAG81\|<20	13.897	9.145	9.306	10.828	19.421
9<\|f8\|/\|SAG82\|<15	12.401	11.737	12.443	13.521	12.804
						\|SAG11/SAG82\|<0.5	0.361	0.458	0.364	0.382	0.333
1<(\|SAG81\|+SAG82)/CT8<2	1.547	1.536	1.723	1.676	1.904
						5<\|f7/SAG72\|<7	5.691	5.373	5.629	6.276	5.952
0<Yc82/SD82<0.5	0.427	0.447	0.400	0.411	0.415
						n1-n8>0.04	0.044	0.044	0.044	0.044	0.044

In a second aspect, referring to fig. 11, the present invention further discloses an image capturing module 200, where the image capturing module 200 includes an image sensor 201 and the optical lens 100 according to any one of the first to fifth embodiments, the image sensor 201 is disposed on an image side of the optical lens 100, and the image sensor 201 is configured to convert an optical signal corresponding to a subject into an image signal, which is not described herein. It can be appreciated that the image capturing module 200 with the optical lens 100 not only can realize the overall miniaturization and wide-viewing design requirements, but also can improve the imaging quality of the image capturing module 200.

In a third aspect, referring to fig. 12, the present invention further discloses an electronic device 300, where the electronic device 300 includes a housing and the camera module 200 as described above, and the camera module 200 is disposed in the housing. Not only can the overall miniaturization and wide-viewing design requirements of the electronic equipment 300 be realized, but also the imaging quality of the electronic equipment 300 can be improved.

The above describes an optical lens, a camera module and an electronic device in detail, and specific examples are applied to illustrate the principles and implementation of the present invention, and the above description of the embodiments is only used to help understand the optical lens, the camera module and the electronic device of the present invention and their core ideas; meanwhile, as those skilled in the art will vary in the specific embodiments and application scope according to the idea of the present invention, the present disclosure should not be construed as limiting the present invention in summary.

Claims

1. An optical lens is characterized by comprising 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 which are sequentially arranged from an object side to an image side along an optical axis;

eight lenses with focal power; at least one of the fourth lens and the fifth lens has negative optical power;

the optical lens satisfies the following relation:

0.15 mm<TTL/(ImgH*2)/f<0.2mm；9<|f8|/|SAG82|<15；5<|f7/SAG72|<7；

wherein TTL is the distance from the object side surface of the first lens element to the imaging surface of the optical lens element on the optical axis, imgH is the radius of the maximum effective imaging circle of the optical lens element, f is the effective focal length of the optical lens element, f8 is the focal length of the eighth lens element, SAG82 is the maximum sagittal height on the image side surface of the eighth lens element, f7 is the focal length of the seventh lens element, SAG72 is the maximum sagittal height on the image side surface of the seventh lens element.

2. The optical lens of claim 1, wherein the optical lens satisfies the following relationship: 1< ImgH/f.

3. The optical lens of claim 1, wherein the optical lens satisfies the following relationship: 8< |f8|/|SAG81| <20;

Wherein f8 is the focal length of the eighth lens, and SAG81 is the maximum sagittal height of the object side surface of the eighth lens.

4. The optical lens of claim 1, wherein the optical lens satisfies the following relationship: the ratio of SAG11/SAG82 is <0.5;

wherein SAG11 is the maximum sagittal height of the object side surface of the first lens, and SAG82 is the maximum sagittal height of the image side surface of the eighth lens.

5. The optical lens of claim 1, wherein the optical lens satisfies the following relationship: 1< | (SAG 81|+SAG 82)/CT 8<2;

wherein SAG81 is the maximum sagittal height of the object side surface of the eighth lens element, SAG82 is the maximum sagittal height of the image side surface of the eighth lens element, and CT8 is the thickness of the eighth lens element on the optical axis.

6. The optical lens of claim 1, wherein the optical lens satisfies the following relationship: 0< yc82/SD82<0.5;

wherein Yc82 is a perpendicular distance between a tangential plane of the image side surface of the eighth lens element at an off-axis position, which is perpendicular to the optical axis, and a tangential point of the image side surface of the eighth lens element, and the optical axis, and SD82 is a maximum effective half-caliber of the image side surface of the eighth lens element.

7. An imaging module, wherein the imaging module comprises an image sensor and the optical lens according to any one of claims 1 to 6, and the image sensor is disposed on an image side of the optical lens.

8. An electronic device, comprising a housing and the camera module of claim 7, wherein the camera module is disposed on the housing.