CN115166949B

CN115166949B - Optical lens, camera module and intelligent terminal

Info

Publication number: CN115166949B
Application number: CN202211087232.6A
Authority: CN
Inventors: 乐宇明; 管磊; 赵迪
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2022-09-07
Filing date: 2022-09-07
Publication date: 2023-01-06
Anticipated expiration: 2042-09-07
Also published as: CN115166949A

Abstract

The invention discloses an optical lens, a camera module and an intelligent terminal, wherein the optical lens 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; the first lens element with negative refractive power, the second lens element with negative refractive power, the third lens element with refractive power, the fourth lens element with positive refractive power, the fifth lens element with positive refractive power, the sixth lens element with refractive power, the seventh lens element with refractive power, the eighth lens element with refractive power, and the optical lens assembly satisfy the following relation: 3< -CT4/SAGs 7<11 >, CT4 is the thickness of the fourth lens on the optical axis, and SAGs7 is the rise of the object-side surface of the fourth lens at the maximum effective half aperture. The optical lens, the camera module and the intelligent terminal provided by the invention can improve the imaging quality of the optical lens, achieve the high-pixel shooting effect, and enable the optical lens to have the characteristics of large aperture and large wide angle while realizing the miniaturized design.

Description

Optical lens, camera module and intelligent terminal

Technical Field

The invention relates to the technical field of optical imaging, in particular to an optical lens, a camera module and an intelligent terminal.

Background

In recent years, with the development of the vehicle-mounted industry, the technical requirements of Advanced Driver Assistance Systems (ADAS), automobile data recorders, and vehicle-mounted cameras for backing images are higher and higher, wherein the ADAS vehicle-mounted camera can accurately capture road information (such as detected objects, detected light sources, detected road signs, etc.) in real time, provide a clear view for the Driver to drive, and clearly record detailed information. However, in the current vehicle-mounted camera applied to ADAS, the pixels are not high enough and the aperture is not large enough in the trend of realizing the miniaturization design, and the vehicle-mounted camera cannot realize the miniaturization design and simultaneously has the characteristics of high pixels and large aperture.

Disclosure of Invention

The embodiment of the invention discloses an optical lens, a camera module and an intelligent terminal, which can improve the imaging quality of the optical lens, achieve the high-pixel shooting effect, and enable the optical lens to have the characteristics of a large aperture and a large wide angle while realizing the miniaturization design.

In order to achieve the above object, in a first aspect, the present invention discloses an optical lens having eight lenses, which includes, in order from an object side to an image side along an optical axis, 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;

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

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

the third lens element with refractive power;

the fourth lens element with positive refractive power has a convex object-side surface and a convex image-side surface at paraxial region;

the fifth lens element with positive refractive power has a convex image-side surface at a paraxial region;

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

the seventh lens element with refractive power;

the eighth lens element with positive refractive power has a convex object-side surface and a convex image-side surface at paraxial region;

the optical lens satisfies the following relation:

3<CT4/SAGs7<11；

wherein, CT4 is the thickness of fourth lens on the optical axis, and SAGs7 is the rise of object side surface at the maximum effective semi-calibre of fourth lens, namely, SAGs7 is the crossing point of object side surface and optical axis of fourth lens reaches the distance that the maximum effective semi-calibre of object side surface of fourth lens is in the optical axis, and the direction of acquiescent first lens's object side surface to the image side surface of eighth lens is the positive direction of optical axis, and when the value of SAGs7 is the negative value, it is located the left side of the crossing point of object side surface and optical axis of fourth lens to show that the projection that the maximum effective calibre of object side surface of fourth lens is in the optical axis is located the right side of the crossing point of object side surface and optical axis of fourth lens when the value of SAGs7 is the positive value, it is shown that the projection that the maximum effective calibre of object side surface of fourth lens is in the optical axis is located the right side of the crossing point of object side surface and optical axis of fourth lens.

In the optical lens provided by the application, the first lens can provide negative refractive power for the optical lens, so that more light rays can be favorably emitted into the optical lens, and the large wide-angle design of the optical lens is realized; and the object side surface of the first lens is convex at the paraxial region and the image side surface of the first lens is concave at the paraxial region, so that the space of the optical lens can be effectively utilized to realize the light and thin miniaturization of the optical lens, and the first lens is favorable for ensuring enough light convergence capability to effectively converge light with large angle. The second lens can provide negative refractive power for the optical lens, and the convex-concave shape of the second lens at the position close to the optical axis is combined with the negative refractive power or the positive refractive power provided by the third lens, so that the width of the light beam is favorably enlarged, and the wide-angle light beam is effectively widened after being refracted and converged by the first lens, thereby increasing the light incoming quantity and being convenient for realizing a large aperture; the fourth lens can provide positive refractive power for the optical lens, so that edge aberration can be corrected, imaging resolution can be improved, and meanwhile, the object side surface and the image side surface of the fourth lens are both convex surfaces and smooth in surface shape, so that deviation of incident angles and emergent angles of light rays with different fields of view can be reduced, and sensitivity is reduced. The fifth lens element can provide positive refractive power for the optical lens, and the image side surface of the fifth lens element is convex, so that the positive refractive power of the optical lens can be reasonably distributed, and the main light convergence capability of the optical lens can be improved; the convex surface design of the object-side surface of the sixth lens element at the paraxial region is favorable for the sixth lens element and the seventh lens element to be cemented together by matching the refractive power of the seventh lens element and the surface design at the paraxial region, so that the chromatic aberration of the optical lens assembly can be reduced and the spherical aberration of the optical lens assembly can be corrected; the eighth lens element can provide positive refractive power for the optical lens element, and can further converge light rays, and the object-side surface and the image-side surface of the eighth lens element are both convex surfaces with smooth surface shapes, so that the deviation of light ray incident angles and light ray emergent angles of different view fields can be reduced, and the sensitivity is reduced.

That is to say, by selecting a proper number of lenses and reasonably configuring the refractive power and the surface shape of each lens, the optical lens has the characteristics of large aperture, large wide angle and the like and has the characteristic of miniaturization, and meanwhile, the detailed information of an object can be captured better, the detailed capability of the optical lens for capturing a shot object is improved, the image quality sense of the optical lens is improved, the resolution and the imaging definition of the optical lens are improved, and the optical lens can have a better imaging effect so as to meet the high-definition imaging requirement of people on the optical lens.

And further causing the optical lens to satisfy the following relational expression: 3< -ct4/SAGs 7<11 > which is advantageous in correcting spherical aberration and chromatic aberration produced by the optical lens front lenses (i.e., the first lens to the third lens) by reasonably restricting the ratio of the center thickness of the fourth lens to the rise of the object-side surface of the fourth lens at the maximum effective half aperture, and also can slow down the degree of deflection of light rays at the object-side surface of the fourth lens, reducing the sensitivity of the optical lens as a whole; meanwhile, the center thickness of the fourth lens and the rise of the object side face of the fourth lens at the maximum effective half aperture can be restrained within a reasonable range, so that the surface form of the fourth lens cannot be excessively distorted, the surface form of the fourth lens is favorably controlled within a range easy to machine and form, and the fourth lens is convenient to machine and form. When the thickness of the fourth lens exceeds the upper limit of the relational expression, the thickness of the fourth lens is too large, so that the light weight and the miniaturization design of the optical lens are not facilitated; when the optical axis is lower than the lower limit of the relational expression, the object side surface of the fourth lens is too bent, so that the processing difficulty of the fourth lens is increased, and the production cost of the fourth lens is increased; meanwhile, the surface of the fourth lens is too curved, so that edge aberration is easily generated, and the improvement of the image quality of the optical lens is not facilitated.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 2.5< -f5/f <5; wherein f5 is a focal length of the fifth lens element, and f is a focal length of the optical lens. When the limitation of the relational expression is met, the fifth lens element can be designed to be a positive lens element, positive refractive power can be provided for the optical lens, chromatic aberration correction is facilitated, the eccentricity sensitivity of the optical lens is reduced, the aberration of the optical lens is facilitated to be corrected, and the imaging resolution is improved. When the refractive power of the fifth lens element exceeds the range of the relationship, the refractive power distribution of the optical lens is not balanced enough, which is not favorable for correcting the aberration of the optical lens and reducing the imaging quality.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: -9.1 sj f67/f < -3.5; wherein f67 is a combined focal length of the sixth lens and the seventh lens, and f is a focal length of the optical lens. When the limitation of the relational expression is met, the whole cemented piece formed by combining the sixth lens and the seventh lens has negative refractive power, the aberration of the optical lens is favorably corrected, and the accumulated tolerance of the two lenses is set to be the tolerance of an integrated lens through the arrangement of the cemented piece, so that the eccentricity sensitivity of the optical lens can be reduced, the tolerance and the assembly sensitivity of the optical lens are reduced, the problem of difficulty in lens process manufacturing and optical lens assembly is solved, and the assembly yield of the optical lens is improved. In addition, the imaging resolution is favorably improved through aberration correction between the gluing pieces. When the aberration of the optical lens exceeds the range of the relational expression, the aberration of the optical lens is not corrected, and the imaging quality is reduced.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 1.5-straw CT3/CT2<4; wherein, CT2 is the thickness of the second lens element on the optical axis, and CT3 is the thickness of the third lens element on the optical axis. Through reasonable configuration of the central thicknesses of the second lens and the third lens, the refractive power relation between the second lens and the third lens can be effectively adjusted, so that the wide-angle and miniaturized design of the optical lens is facilitated, and the optical performance of the optical lens is improved; the thickness configuration of the two lenses can be controlled to be uniform, the deflection optical path of light passing through the lenses can be balanced, the deflection angle of the light is not too large, the emergent angle of the light out of the optical lens can be reduced, the situation that the light with large angle can not be effectively converged to an imaging surface can be avoided, the sensitivity of a photosensitive chip is improved, the characteristic of the large image surface of the optical lens can be realized, the photosensitive chip with higher pixels can be matched, the imaging quality is improved, meanwhile, the edge of the imaging surface of the optical lens can obtain higher relative brightness, and the possibility that the optical lens generates a dark angle is reduced.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 9-and-once TTL/f <11; wherein, TTL is a distance on an optical axis from an object side surface of the first lens element to an imaging surface of the optical lens, that is, an optical total length of the optical lens, and f is a focal length of the optical lens. By limiting the relation between the total optical length of the optical lens and the focal length of the optical lens, the total optical length of the optical lens can be controlled within a proper range while the field angle range of the optical lens is met, so that the miniaturization design requirement of the optical lens is met. When the optical length exceeds the upper limit of the relational expression, the optical total length of the optical lens is too long, which is not beneficial to miniaturization design; when the focal length of the optical lens is lower than the lower limit of the relational expression, the focal length of the optical lens is too long, so that the design requirement of the field angle range of the optical lens is difficult to meet, and sufficient object space information cannot be obtained, so that imaging information is lost, and the shooting quality of the optical lens is influenced.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 4.5-sj f8/CT8<14.6; wherein f8 is a focal length of the eighth lens element, and CT8 is a thickness of the eighth lens element on the optical axis. By satisfying the above relational expression, the positive refractive power provided by the eighth lens element can be controlled within a reasonable range, which is beneficial to correcting the field curvature, astigmatism and distortion of the optical lens, thereby ensuring the imaging quality of the optical lens. When the focal length of the eighth lens element exceeds the upper limit of the above relational expression, the refractive power of the eighth lens element is too large, which is not conducive to suppressing high-order aberrations, such that high-order spherical aberration and coma aberration are likely to occur, thereby affecting the resolution and the imaging quality of the optical lens system; when the refractive power is lower than the lower limit of the above relation, the focal length of the eighth lens element is too small, which results in too strong refractive power, and the deflection angle of the light in each field is large, which is likely to generate large aberration and affect the imaging quality.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation:

8-Ap FOV/CRA <9; the FOV is the maximum field angle of the optical lens, and the CRA is the chief ray incident angle of the optical lens. When the relational expression is satisfied, a required large field angle can be provided for the optical lens, and meanwhile, the incident angle of light rays entering the photosensitive chip can be reduced, so that the photosensitive performance is improved, and the wide-angle and high-pixel shooting effect is realized. In addition, the allowable error value between the chief ray incident angle of the optical lens and the chief ray incident angle of the photosensitive chip is larger, and the adaptive capacity of the optical lens to the photosensitive chip is improved.

As an alternative implementation, in an embodiment of the first aspect of the invention, the optical lens satisfies the following relation: 1.5< -f/EPD <1.85; wherein f is the focal length of the optical lens, and EPD is the entrance pupil diameter of the optical lens. When the relational expression is satisfied, the focal length of the optical lens and the entrance pupil diameter of the optical lens can be reasonably configured, so that the optical lens has a larger aperture and a smaller total optical length, the wide-angle characteristic of the optical lens can be ensured, the light ray bundle entering the optical lens can be increased, the optical lens has a larger light inlet amount, sufficient light rays can be gathered and imaged on an imaging surface, the imaging brightness is improved, and a high-definition wide-angle shooting effect is realized; the larger light incoming amount is also convenient for capturing the details of the shot object well, the imaging resolution of the optical lens is improved, and the optical lens has better optical performance even if the optical lens is used in dark light environments such as cloudy days and rainy days. In addition, the larger diameter of the entrance pupil is beneficial to the entrance of large-angle light rays into the optical lens, so that the optical lens has a large field angle range, sufficient object space information can be obtained, and the imaging quality is improved. When the light quantity exceeds the upper limit of the relational expression, the aperture of the optical lens is easy to be too small, which is not beneficial to obtaining enough light inlet quantity in a dark shooting environment, so that the brightness of an imaging surface is reduced, and the imaging quality is not high; when the distance is lower than the lower limit of the above relational expression, the focal length of the optical lens is too small to meet the design requirement of the field angle range of the optical lens, and sufficient object space information cannot be obtained, so that the imaging information is lost, and the shooting quality of the optical lens is affected.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 50deg < (FOV x f)/Y <60deg; the FOV is the maximum field angle of the optical lens, f is the focal length of the optical lens, and Y is the diameter of the maximum effective imaging circle on the imaging surface of the optical lens, namely the image height of the optical lens. When the relation is satisfied, the good optical performance of the optical lens can be maintained, the high-pixel characteristic of the optical lens can be realized, the details of a shot object can be well captured, the large field angle can be obtained, and the deflection angle of emergent light can be reduced, so that the dark angle is reduced, the distortion is restrained, and the shooting effect of the optical lens is improved.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: TTL/(Y/2) <1.65 is more than or equal to 1.55; wherein, TTL is a distance on an optical axis from an object side surface of the first lens element to an imaging surface of the optical lens, and Y is a diameter of a maximum effective imaging circle on the imaging surface of the optical lens, that is, an image height of the optical lens. The ratio of the total optical length to the image height of the optical lens is controlled within a reasonable range, the total optical length of the optical lens can be effectively controlled on the premise that the optical lens has a large field angle and an image surface, the structure of the optical lens is more compact, the optical lens has ultrathin characteristics, the miniaturization design requirement is met, the optical lens can be better carried on a light and thin intelligent terminal, meanwhile, the optical lens can be compatible with a large-size photosensitive chip, and the imaging quality of the intelligent terminal is favorably improved. When the optical total length of the optical lens exceeds the upper limit of the relational expression, the thickness of the optical lens in the optical axis direction is increased, the light, thin and small design of the optical lens is not facilitated, and meanwhile, the size of an imaging surface of the optical lens is too small, so that a dark angle phenomenon is easily generated, imaging information is lost, and the imaging quality is reduced; when the optical length is less than the lower limit of the above relational expression, the total optical length of the optical lens is too small, which is not favorable for lens arrangement and reduces the assembly efficiency of the optical lens.

In a second aspect, the present invention discloses a camera module, which includes a photosensitive chip and the optical lens according to the first aspect, wherein the photosensitive chip is disposed on an image side of the optical lens. Have optical lens's the module of making a video recording can improve optical lens's imaging quality, reaches the shooting effect of high pixel, but also can make optical lens have big light ring and big wide-angle's characteristics concurrently when realizing miniaturized design.

In a third aspect, the invention further discloses an intelligent terminal, which comprises a terminal main body and the camera module set according to the second aspect, wherein the camera module set is arranged on the terminal main body. Have the intelligent terminal of module of making a video recording can improve optical lens's imaging quality, reaches the shooting effect of high pixel, but also enables optical lens and has the characteristics of big light ring and big wide angle concurrently when realizing miniaturized design.

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

according to the optical lens, the camera module and the intelligent terminal provided by the embodiment of the invention, the optical lens adopts eight-piece type lenses, the number of the lenses is reasonable, the structure is ingenious, and the volume is small. The optical lens has the characteristics of large aperture, large wide angle and the like and simultaneously has the characteristic of miniaturization by selecting a proper number of lenses and reasonably configuring the refractive power and the surface type of each lens, can better capture the detailed information of an object, improves the detailed capability of the optical lens for capturing the shot object, improves the image quality of the optical lens, improves the resolution and the imaging definition of the optical lens, and has better imaging effect so as to meet the high-definition imaging requirement of people on the optical lens; and further causing the optical lens to satisfy the following relational expression: 3< -ct4/SAGs 7<11 > which is advantageous in correcting spherical aberration and chromatic aberration produced by the optical lens front lenses (i.e., the first lens to the third lens) by reasonably restricting the ratio of the center thickness of the fourth lens to the rise of the object-side surface of the fourth lens at the maximum effective half aperture, and also can slow down the degree of deflection of light rays at the object-side surface of the fourth lens, reducing the sensitivity of the optical lens as a whole; meanwhile, the central thickness of the fourth lens and the rise of the object side surface of the fourth lens at the maximum effective semi-aperture position can be restrained within a reasonable range, so that the surface shape of the fourth lens cannot be excessively distorted, the surface shape of the fourth lens is favorably controlled within a range easy to machine and form, and the fourth lens is convenient to machine and form.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used 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 it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an optical lens disclosed in a first embodiment of the present application;

fig. 2 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical lens disclosed in the first embodiment of the present application;

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

fig. 4 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical lens disclosed in a second embodiment of the present application;

fig. 5 is a schematic structural diagram of an optical lens disclosed in a third embodiment of the present application;

fig. 6 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical lens disclosed in a third embodiment of the present application;

fig. 7 is a schematic structural diagram of an optical lens disclosed in a fourth embodiment of the present application;

fig. 8 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical lens disclosed in a fourth embodiment of the present application;

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

fig. 10 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical lens disclosed in a fifth embodiment of the present application;

fig. 11 is a schematic structural diagram of the camera module disclosed in the present application;

fig. 12 is a schematic structural diagram of the intelligent terminal disclosed in the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

In the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "center", "vertical", "horizontal", "lateral", "longitudinal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the invention and its embodiments and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

Furthermore, the terms "mounted," "disposed," "provided," "connected," and "connected" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; can 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 meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

Moreover, the terms "first," "second," and the like, are used primarily to distinguish one device, element, or component from another (the specific type and configuration may or may not be the same), and are not used to indicate or imply the relative importance or number of the indicated devices, elements, or components. "plurality" means two or more unless otherwise specified.

The technical solution of the present invention will be further described with reference to the following examples and drawings.

Referring to fig. 1, according to a first aspect of the present application, an optical lens 100 is disclosed, where the optical lens 100 includes a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4, a fifth lens element L5, a sixth lens element L6, a seventh lens element L7, and an eighth lens element 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 image plane 101 of the optical lens 100. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive or negative refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive or negative refractive power, the seventh lens element L7 with positive or negative refractive power, and the eighth lens element L8 with positive refractive power.

Further, the object-side surface S1 of the first lens element L1 can be convex at a paraxial region, and the image-side surface S2 of the first lens element L1 can be concave at a paraxial region; the object-side surface S3 of the second lens element L2 can be convex at a paraxial region, and the image-side surface S4 of the second lens element L2 can be concave at a paraxial region; the object-side surface S5 of the third lens element L3 is convex or concave at the paraxial region, and the image-side surface S6 of the third lens element L3 is convex or concave at the paraxial region; the object-side surface S7 of the fourth lens element L4 can be convex at a paraxial region, and the image-side surface S8 of the fourth lens element L4 can be convex at a paraxial region; the object-side surface S9 of the fifth lens element L5 can be convex or concave at a paraxial region, and the image-side surface S10 of the fifth lens element L5 can be convex at a paraxial region; the object-side surface S11 of the sixth lens element L6 can be convex at a paraxial region, and the image-side surface S12 of the sixth lens element L6 can be concave or convex at a paraxial region; the object-side surface S13 of the seventh lens element L7 can be convex or concave at a paraxial region, and the image-side surface S14 of the seventh lens element L7 can be concave or convex at a paraxial region; the object-side surface S15 of the eighth lens element L8 can be convex at a paraxial region, and the image-side surface S16 of the eighth lens element L8 can be convex at a paraxial region.

It is considered that the optical lens 100 is often used in electronic devices such as an in-vehicle device and a drive recorder or in an automobile. When the optical lens 100 is used as a camera on an automobile body, 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 can all be glass lenses, so that the optical lens 100 has a good optical effect, and the temperature sensitivity of the optical lens 100 can be reduced. Further, in the first lens L1 to the eighth lens L8, the object-side surface and/or the image-side surface of one of the lenses may be aspheric, which is favorable for correcting the aberration of the optical lens 100 and improving the imaging quality of the optical lens 100. Illustratively, the object-side surface S5 of the third lens L3, the image-side surface S6 of the third lens L3, the object-side surface S9 of the fifth lens L5, the image-side surface S10 of the fifth lens L5, the object-side surface S15 of the eighth lens L8, and the image-side surface S16 of the eighth lens L8 are aspheric, the object-side surface S11 of the sixth lens L6 is aspheric, the image-side surface S12 of the sixth lens L6 is spherical, and the object-side surface and the image-side surface of the first lens L1, the second lens L2, the fourth lens L4, and the seventh lens L7 can be spherical for ease of processing and molding.

In addition, it is understood that, in other embodiments, when the optical lens 100 is applicable to an electronic device such as a smart phone and a smart tablet, 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 also be plastics, and each of the lenses may adopt an aspheric surface. That is, 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 aspheric.

In some embodiments, the optical lens 100 further includes a stop 102, and the stop 102 may be an aperture stop or a field stop, which may be disposed between the fourth lens L4 and the fifth lens L5, i.e., the stop 102 may be disposed between the image side surface S8 of the fourth lens L4 and the object side surface S9 of the fifth lens L5. It is understood that, in other embodiments, the stop 102 may also be disposed between the object side of the optical lens 100 and the object side surface S1 of the first lens L1, and the setting is adjusted according to practical situations, which is not particularly limited in this embodiment.

In some embodiments, the optical lens 100 further includes a filter L9, for example, an infrared filter, where the infrared filter may be disposed between the image side surface S16 of the eighth lens element L8 and the imaging surface 101 of the optical lens 100, so as to filter infrared light and only allow visible light to pass through, and at this time, the infrared cut filter is selected, so as to improve imaging quality and make imaging better conform to visual experience of human eyes; of course, the filter L9 may also filter light in other bands, such as visible light, and only allow infrared light to pass through, so that the infrared band pass filter is selected at this time, and the optical lens 100 may be used as an infrared optical lens by filtering light in other bands, such as visible light, and the optical lens 100 may also image in a dark environment and in other special application scenes, and may obtain a better image effect. It is understood that the optical filter L9 may be made of an optical glass coating film, may also be made of colored glass, or may be a filter made of other materials, which may be selected according to actual needs, and is not limited in this embodiment.

In some embodiments, the optical lens 100 satisfies the following relationship: 3-Tn CT4/SAGs7<11; for example, CT4/SAGs7=3.277, 3.015, 3.456, 4.678, 5.423, 6.357, 7.127, 8.809, 9.416, 10.318, 10.963, and so on, where CT4 is the thickness of the fourth lens L4 on the optical axis O, SAGs7 is the sagittal height of the object-side surface S7 of the fourth lens L4 at the maximum effective semi-aperture, that is, SAGs7 is the distance from the intersection of the object-side surface S7 of the fourth lens L4 and the optical axis O to the maximum effective semi-aperture of the object-side surface S7 of the fourth lens L4 on the optical axis O, the direction from the object-side surface S1 of the first lens L1 to the image-side surface S16 of the eighth lens L8 is the positive direction of the optical axis O, and when the value of SAGs7 is negative, it is indicated that the projection of the maximum effective side surface S7 of the fourth lens L4 on the optical axis O is located on the left side of the intersection of the object-side surface S7 of the fourth lens L4 and the optical axis O, and when the value of SAGs7 is negative, it is indicated that the projection of the maximum effective semi-aperture S7 of the fourth lens L4 is located on the right side of the optical axis O.

By reasonably restricting the ratio of the central thickness of the fourth lens L4 to the rise of the object-side surface S7 of the fourth lens L4 at the maximum effective half aperture, the spherical aberration and the chromatic aberration generated by the front lenses (i.e., the first lens L1 to the third lens L3) of the optical lens 100 can be corrected favorably, and meanwhile, the deflection degree of light rays at the object-side surface S7 of the fourth lens L4 can be reduced, so that the overall sensitivity of the optical lens 100 is reduced; meanwhile, the central thickness of the fourth lens L4 and the rise of the object side surface S7 of the fourth lens L4 at the maximum effective semi-aperture position can be restrained within a reasonable range, so that the surface shape of the fourth lens L4 cannot be excessively distorted, the surface shape of the fourth lens L4 is favorably controlled within a range easy to machine and form, and the fourth lens L4 is convenient to machine and form. On the other hand, if the upper limit of the above relation is exceeded, the thickness of the fourth lens L4 is too large, which is disadvantageous to the light weight and compact design of the optical lens 100; when the value is lower than the lower limit of the relational expression, the object-side surface S7 of the fourth lens L4 is too curved, so that the processing difficulty of the fourth lens L4 is increased, and the production cost of the fourth lens L4 is increased; meanwhile, the surface of the fourth lens element L4 is too curved, which is prone to generate edge aberration, and is not favorable for improving the image quality of the optical lens system 100.

In some embodiments, the optical lens 100 satisfies the following relationship: 2.5 sj f5/f <5; for example, f5/f =2.536, 2.745, 2.918, 3.118, 3.459, 3.851, 4.109, 4.637, 4.843, or 4.972, etc., where f5 is the focal length of the fifth lens L5 and f is the focal length of the optical lens 100. When the limitation of the above relation is satisfied, the fifth lens element L5 can be designed as a positive lens element, which can provide positive refractive power for the optical lens 100, thereby facilitating the correction of chromatic aberration, reducing the decentering sensitivity of the optical lens 100, facilitating the correction of aberration of the optical lens 100, and improving the imaging resolution. When the refractive power of the fifth lens element L5 exceeds the range of the relationship, the refractive power distribution of the optical lens system 100 is not balanced enough, which is not favorable for correcting the aberration of the optical lens system 100 and reducing the image quality.

In some embodiments, the optical lens 100 satisfies the following relationship: -9.1 sj f67/f < -3.5; for example, f67/f = -9.099, -8.723, -8.047, -7.792, -7.108, -6.904, -6.275, -5.621, -5.155, -4.721, -4.447, -3.638, or-3.593, etc., where f67 is the combined focal length of the sixth lens L6 and the seventh lens L7, and f is the focal length of the optical lens 100. When the limitation of the above relation is satisfied, the whole cemented piece formed by combining the sixth lens element L6 and the seventh lens element L7 has negative refractive power, which is beneficial to correcting the aberration of the optical lens 100, and the accumulated tolerance of the two lens elements is set to the tolerance of an integrated lens element through the arrangement of the cemented piece, so that the decentering sensitivity of the optical lens 100 can be reduced, the tolerance and the assembly sensitivity of the optical lens 100 can be reduced, the problem that the manufacturing process of the lens elements and the assembly of the optical lens 100 are difficult is solved, and the assembly yield of the optical lens 100 is improved. In addition, the imaging resolution is favorably improved through aberration correction between the gluing pieces. If the range exceeds the relational expression, the aberration of the optical lens 100 is not corrected, and the imaging quality is degraded.

In some embodiments, the optical lens 100 satisfies the following relationship: 1.5-straw CT3/CT2<4; for example, CT3/CT2=1.521, 1.557, 1.600, 2.105, 2.307, 2.600, 2.769, 3.014, 3.336, 3.589, 3.547, or 3.869, and the like, where CT2 is a thickness of the second lens L2 on the optical axis O, and CT3 is a thickness of the third lens L3 on the optical axis O. Through reasonable configuration of the central thicknesses of the second lens element L2 and the third lens element L3, the refractive power relationship between the second lens element L2 and the third lens element L3 can be effectively adjusted, thereby facilitating realization of the wide-angle and miniaturized design of the optical lens 100 and improving the optical performance of the optical lens 100; and the thickness configuration of the two lenses can be controlled to be uniform, so that the deflection optical path of light passing through the lenses can be balanced, the deflection angle of the light is not too large, the emergent angle of the light out of the optical lens 100 can be reduced, the phenomenon that the light with large angle can not be effectively converged to the imaging surface 101 can be avoided, the sensitivity of a photosensitive chip is improved, the characteristic of the large image surface of the optical lens 100 can be realized, the photosensitive chip with higher pixels can be matched, the imaging quality is improved, meanwhile, the edge of the imaging surface 101 of the optical lens 100 can obtain higher relative brightness, and the possibility of generating a dark angle by the optical lens 100 is reduced.

In some embodiments, the optical lens 100 satisfies the following relationship: 9< -TTL/f <11; for example, TTL/f =9.207, 9.468, 9.726, 9.984, 10.061, 10.250, 10.372, 10.457, 10.527, 10.716, or 10.946, where TTL is a distance from the object-side surface S1 of the first lens L1 to the image plane 101 of the optical lens 100 on the optical axis O, i.e., the total optical length of the optical lens 100, and f is a focal length of the optical lens 100. By defining the relationship between the total optical length of the optical lens 100 and the focal length of the optical lens 100, the total optical length of the optical lens 100 can be controlled within a suitable range while satisfying the field angle range of the optical lens 100, so as to satisfy the design requirement of miniaturization of the optical lens 100. When the upper limit of the above relation is exceeded, the total optical length of the optical lens 100 is too long, which is not favorable for miniaturization design; when the focal length is lower than the lower limit of the above relational expression, the focal length of the optical lens 100 is too long, so that it is difficult to meet the design requirement of the field angle range of the optical lens 100, and sufficient object space information cannot be obtained, resulting in missing of imaging information and affecting the shooting quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship: 4.5-sj f8/CT8<14.6; for example, f8/CT8=4.826, 5.099, 5.291, 6.206, 7.318, 8.089, 8.713, 9.345, 9.912, 10.237, 10.982, 11.549, 12.386, 13.546, 13.895, or 14.515, etc., where f8 is the focal length of the eighth lens L8, and CT8 is the thickness of the eighth lens L8 on the optical axis O. By satisfying the above relational expression, the positive refractive power provided by the eighth lens element L8 can be controlled within a reasonable range, which is beneficial to correcting curvature of field, astigmatism and distortion of the optical lens 100, thereby ensuring the imaging quality of the optical lens 100. When the upper limit of the above relation is exceeded, the focal length of the eighth lens element L8 is too large, which results in insufficient refractive power and is not favorable for suppressing high-order aberration, so that phenomena such as high-order spherical aberration and coma aberration are likely to occur, which affect the resolution and the imaging quality of the optical lens 100; when the focal length is less than the lower limit of the above relational expression, the focal length of the eighth lens element L8 is too small, which causes too strong refractive power and is liable to generate large aberration, thereby affecting the imaging quality.

In some embodiments, the optical lens 100 satisfies the following relationship: 8-Ap FOV/CRA <9; for example, FOV/CRA =8.169, 8.216, 8.367, 8.493, 8.564, 8.598, 8.627, 8.658, 8.742, 8.805, 8.882, or 8.976, etc., where FOV is the maximum field angle of optical lens 100 and CRA is the chief ray incident angle of optical lens 100. When the above relation is satisfied, a required large field angle can be provided for the optical lens 100, and meanwhile, the incident angle of light rays entering the photosensitive chip can be reduced, the photosensitive performance is improved, and a wide-angle and high-pixel shooting effect is realized. In addition, the allowable error value between the chief ray incident angle of the optical lens 100 and the chief ray incident angle of the photosensitive chip is larger, and the adaptive capacity of the optical lens 100 to the photosensitive chip is improved.

In some embodiments, the optical lens 100 satisfies the following relationship: 1.5-straw f/EPD <1.85; for example, f/EPD =1.510, 1.520, 1.550, 1.600, 1.650, 1.700, 1.750, 1.800, 1.820, or 1.840, etc., where f is the focal length of the optical lens 100 and EPD is the entrance pupil diameter of the optical lens 100. When the above relation is satisfied, the focal length of the optical lens 100 and the diameter of the entrance pupil of the optical lens 100 may be reasonably configured, which is beneficial to making the optical lens 100 have a larger aperture and a smaller total optical length, and simultaneously, the wide-angle characteristic of the optical lens 100 may also be ensured, which is beneficial to increasing the light beam entering the optical lens 100, so as to make the optical lens 100 have a larger light-entering amount, thereby ensuring that enough light may be converged and imaged on the imaging surface 101, improving the brightness of the imaged image, and further realizing a high-definition wide-angle shooting effect; the larger light input amount is also convenient for capturing details of the object to be photographed well, improves the imaging resolution of the optical lens 100, and has better optical performance even if used in dark light environments such as cloudy days and rainy days. In addition, the larger diameter of the entrance pupil is also beneficial to the entrance of large-angle light rays into the optical lens 100, so that the optical lens 100 has a large field angle range, sufficient object space information can be obtained, and the imaging quality is improved. If the upper limit of the above relational expression is exceeded, the aperture of the optical lens 100 is easily too small, which is not favorable for obtaining a sufficient light entering amount in a dark shooting environment, so that the brightness of the imaging plane 101 is reduced, and the imaging quality is not high; if the distance is less than the lower limit of the above relational expression, the focal length of the optical lens 100 is too small to meet the design requirement of the field angle range of the optical lens 100, and sufficient object space information cannot be obtained, resulting in missing of imaging information and affecting the shooting quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship: 50deg < - (FOV f)/Y <60deg; for example, (FOV x f)/Y =50.951 deg, 51.887 deg, 52.829 deg, 53.128 deg, 54.396 deg, 55.089 deg, 56.022 deg, 57.891 deg, 58.267 deg, 59.024 deg, or 59.687 deg, etc., where FOV is the maximum field angle of the optical lens 100, f is the focal length of the optical lens 100, and Y is the diameter of the maximum effective imaging circle on the imaging plane 101 of the optical lens 100, i.e., the image height of the optical lens 100. When the above relational expression is satisfied, the good optical performance of the optical lens 100 can be maintained, the high-pixel characteristic of the optical lens 100 can be realized, the details of the object to be photographed can be well captured, and the large field angle can be obtained, and the deflection angle of the emergent light can be reduced, so that the dark angle can be reduced, the distortion can be suppressed, and the shooting effect of the optical lens 100 can be improved.

In some embodiments, the optical lens 100 satisfies the following relationship: TTL/(Y/2) <1.65 is more than or equal to 1.55; for example, TTL/(Y/2) = 1.550, 1.559, 1.561, 1.574, 1.579, 1.583, 1.588, 1.593, 1.595, 1.596, 1.604, 1.639, or 1.648, etc., where TTL is the distance between the object-side surface S1 of the first lens L1 and the image plane 101 of the optical lens 100 on the optical axis O, and Y is the diameter of the maximum effective imaging circle on the image plane 101 of the optical lens 100, that is, the image height of the optical lens 100. By controlling the ratio of the total optical length to the image height of the optical lens 100 within a reasonable range, the total optical length of the optical lens 100 can be effectively controlled on the premise that the optical lens 100 has a larger field angle and an image plane, so that the optical lens 100 has a more compact structure and an ultrathin characteristic, and meets the design requirement of miniaturization, so that the optical lens 100 can be better carried on a light and thin intelligent terminal, and meanwhile, the optical lens 100 can be compatible with a large-sized photosensitive chip, thereby being beneficial to improving the imaging quality of the intelligent terminal. When the total optical length of the optical lens 100 exceeds the upper limit of the above relational expression, the thickness of the optical lens 100 in the optical axis direction is increased due to an excessively large total optical length, which is not favorable for the light, thin and miniaturized design of the optical lens 100, and meanwhile, the size of the imaging surface 101 of the optical lens 100 is excessively small, which is easy to generate a dark angle phenomenon, thereby causing loss of imaging information and reducing imaging quality; when the lower limit of the above relation is lower, the total optical length of the optical lens 100 is too small, which is not favorable for lens arrangement and reduces the assembling efficiency of the optical lens 100.

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

First embodiment

As shown in fig. 1, the optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop 102, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter L9, which are sequentially disposed along an optical axis O from an object side to an image side. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, the seventh lens element L7 with positive refractive power, and the eighth lens element L8 with positive refractive power. For 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, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, the object-side surface S1 of the first lens element L1 is convex at a paraxial region, and the image-side surface S2 of the first lens element L1 is concave at a paraxial region; the object-side surface S3 of the second lens element L2 is convex at a paraxial region, and the image-side surface S4 of the second lens element L2 is concave at a paraxial region; the object-side surface S5 of the third lens element L3 is concave at the paraxial region, and the image-side surface S6 of the third lens element L3 is convex at the paraxial region; the object-side surface S7 of the fourth lens element L4 and the image-side surface S8 of the fourth lens element are convex at the paraxial region; the object-side surface S9 of the fifth lens element L5 and the image-side surface S10 of the fifth lens element L5 are convex at the paraxial region; the object-side surface S11 of the sixth lens element L6 is convex at a paraxial region, and the image-side surface S12 of the sixth lens element L6 is concave at a paraxial region; the object-side surface S13 of the seventh lens element L7 is convex at the paraxial region, and the image-side surface S14 of the seventh lens element L7 is convex at the paraxial region; the object-side surface S15 of the eighth lens element L8 and the image-side surface S16 of the eighth lens element L8 are convex at the paraxial region. Further, the image-side surface S12 of the sixth lens L6 is cemented with the object-side surface S13 of the seventh lens L7.

Specifically, taking the focal length f =3.7mm of the optical lens 100, the maximum field angle FOV =168deg of the optical lens 100, and the f-number FNO =1.6 of the optical lens 100 as an example, other parameters of the optical lens 100 are given in table 1 below. The elements of the optical lens 100 from the object side to the image side along the optical axis O are arranged in the order of the elements from top to bottom in table 1. In the same lens, the surface with the smaller surface number is the object side surface of the lens, and the surface with the larger surface number is the image side surface of the lens, and for example, the surface numbers 1 and 2 correspond to the object side surface S1 and the image side surface S2 of the first lens L1, respectively. The Y radius in table 1 is the radius of curvature of the object or image side at the paraxial region for the respective face number. The first value in the "thickness" parameter column 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 to the back surface of the lens on the optical axis O. The numerical value of the stop 102 in the "thickness" parameter column is the distance on the optical axis O from the stop 102 to the vertex of the next surface (the vertex refers to the intersection point of the surface and the optical axis O), the direction from the object side surface of the first lens L1 to the image side surface of the last lens is the positive direction of the optical axis O, when the value is negative, it indicates that the stop 102 is disposed on the right side of the vertex of the next surface, and if the thickness of the stop 102 is a positive value, the stop 102 is disposed on the left side of the vertex of the next surface. It is understood that the units of the radius Y, thickness, and focal length in table 1 are all mm. The reference wavelength of the focal length of each lens in table 1 is 546.00nm, and the reference wavelengths of the refractive index and abbe number of each lens are 587.60nm.

TABLE 1

In the first embodiment, the object-side surface and the image-side surface of any one of the third lens L3, the fifth lens L5 and the eighth lens L8 are aspheric, and the profile x of each aspheric lens can be defined by, but is not limited to, the following aspheric formula:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c =1/R (i.e., paraxial curvature c is the inverse of radius R of Y in table 1 above); k is the cone coefficient; ai is a correction coefficient corresponding to the high-order term of the ith aspheric term. Table 2 shows the high-order term coefficients A4, A6, A8, a10, a12, a14, a16, a18, and a20 of the respective aspherical mirror surfaces usable in the third lens L3, the fifth lens L5, and the eighth lens L8 in the first embodiment.

TABLE 2

Referring to fig. 2 (a), fig. 2 (a) shows a longitudinal spherical aberration curve of the optical lens 100 in the first embodiment at wavelengths of 420.00nm, 435.00mm, 486.00nm, 546.00mm, 588.00mm, and 656.00 nm. In fig. 2 (a), the abscissa in the X-axis direction represents the focus shift in mm, and the ordinate in 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 this embodiment is better.

Referring to fig. 2 (B), fig. 2 (B) is a graph of astigmatism of the optical lens 100 in the first embodiment at a wavelength of 546.00 nm. In fig. 2 (B), the abscissa in the X-axis direction represents the focus shift in mm, and the ordinate in the Y-axis direction represents the angle of view in deg. T in the astigmatism graph indicates the curvature of the imaging plane 101 in the meridional direction, and S indicates the curvature of the imaging plane 101 in the sagittal direction, and it can be seen from (B) in fig. 2 that the astigmatism of the optical lens 100 is well compensated for at the wavelength 546.00 nm.

Referring to fig. 2 (C), fig. 2 (C) is a distortion curve diagram of the optical lens 100 in the first embodiment at a wavelength of 546.00 nm. Wherein the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents field angle in deg. As can be seen from (C) in fig. 2, the distortion of the optical lens 100 is well corrected at the wavelength 5456.00 nm.

Second embodiment

Referring to fig. 3, fig. 3 is a schematic structural diagram of an optical lens 100 according to a second embodiment of the present application. The optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop 102, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter L9, which are disposed in this order from the object side to the image side along an optical axis O. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive refractive power, the seventh lens element L7 with negative refractive power, and the eighth lens element L8 with positive refractive power. For 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, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, in the second embodiment, the surface shape of each lens is different from that of each lens in the first embodiment in that: the image-side surface S12 of the sixth lens element L6 is convex at the paraxial region, and the object-side surface S13 of the seventh lens element L7 and the image-side surface S14 of the seventh lens element L7 are concave at the paraxial region. Further, the image-side surface S12 of the sixth lens L6 is cemented with the object-side surface S13 of the seventh lens L7.

In the second embodiment, the focal length f =3.8mm of the optical lens 100, the maximum field angle FOV =171deg of the optical lens 100, and the f-number FNO =1.8 of the optical lens 100 are taken as examples. Other parameters in the second embodiment are given in the following table 3, and the definitions of the parameters can be obtained from the description of the foregoing embodiments, which are not repeated herein. It is understood that the units of the radius Y, thickness, and focal length in table 3 are mm. In Table 3, the reference wavelength of the focal length of each lens is 546.00nm, and the reference wavelengths of the refractive index and Abbe number of each lens are 587.60nm.

TABLE 3

In the second embodiment, table 4 gives the high-order term coefficients of each aspherical mirror surface usable in the third lens L3, the fifth lens L5, and the eighth lens L8 in the second embodiment, wherein each aspherical mirror surface type can be defined by the formula given in the first embodiment.

TABLE 4

Referring to fig. 4, fig. 4 shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of the optical lens 100 according to the second embodiment, and specific definitions are described with reference to the first embodiment and will not be repeated herein. As can be seen from fig. 4 (a), the spherical aberration value of the optical lens 100 in the second embodiment is better, which illustrates that the imaging quality of the optical lens 100 in the present embodiment is better. As can be seen from (B) in fig. 4, astigmatism of the optical lens 100 is well compensated at a wavelength of 546.00 nm. As can be seen from (C) in fig. 4, the distortion of the optical lens 100 is well corrected at a wavelength of 546.00 nm.

Third embodiment

Referring to fig. 5, fig. 5 shows a schematic structural diagram of an optical lens 100 according to a third embodiment of the present application. The optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop 102, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter L9, which are disposed in order from an object side to an image side along an optical axis O. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive refractive power, the seventh lens element L7 with negative refractive power, and the eighth lens element L8 with positive refractive power. As for 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, reference may be made to the above detailed description, and details thereof are not repeated here.

Further, in the third embodiment, the surface shape of each lens is different from that of each lens in the first embodiment in that: the image-side surface S12 of the sixth lens element L6 is convex at the paraxial region, and the object-side surface S13 of the seventh lens element L7 and the image-side surface S14 of the seventh lens element L7 are concave at the paraxial region. Further, the image-side surface S12 of the sixth lens L6 is cemented with the object-side surface S13 of the seventh lens L7.

In the third embodiment, the focal length f =3.9mm of the optical lens 100, the maximum field angle FOV =171deg of the optical lens 100, and the f-number FNO =1.8 of the optical lens 100 are taken as examples.

Other parameters in the third embodiment are shown in the following table 5, and the definitions of the parameters can be obtained from the foregoing description, which is not repeated herein. It is understood that the units of the radius Y, thickness, and focal length in table 5 are mm. In table 5, the reference wavelength of the focal length of each lens is 546.00nm, and the reference wavelengths of the refractive index and abbe number of each lens are 587.60nm.

TABLE 5

In the third embodiment, table 6 gives the high-order term coefficients of each aspherical mirror surface usable in the third lens L3, the fourth lens L4, and the eighth lens L8 in the third embodiment, wherein each aspherical mirror surface type can be defined by the formula given in the first embodiment.

TABLE 6

Referring to fig. 6, fig. 6 shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of an optical lens 100 according to a third embodiment, and specific definitions are described with reference to the first embodiment and will not be described herein again. As can be seen from fig. 6 (a), the spherical aberration value of the optical lens 100 in the third embodiment is better, which indicates that the imaging quality of the optical lens 100 in this embodiment is better. As can be seen from (B) in fig. 6, astigmatism of the optical lens 100 is well compensated at a wavelength of 546.00 nm. As can be seen from (C) in fig. 6, the distortion of the optical lens 100 is well corrected at a wavelength of 546.00 nm.

Fourth embodiment

Fig. 7 is a schematic structural diagram of an optical lens 100 according to a fourth embodiment of the present disclosure. The optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a stop 102, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter L9, which are disposed in order from an object side to an image side along an optical axis O. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive refractive power, the seventh lens element L7 with negative refractive power and the eighth lens element L8 with positive refractive power. For 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, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, in the fourth embodiment, the surface shape of each lens is different from that of each lens in the first embodiment in that: the object-side surface S5 of the third lens element L3 is convex at the paraxial region, the image-side surface S6 of the third lens element L3 is concave at the paraxial region, the object-side surface S9 of the fifth lens element L5 is concave at the paraxial region, the image-side surface S12 of the sixth lens element L6 is convex at the paraxial region, and the object-side surface S13 of the seventh lens element L7 and the image-side surface S14 of the seventh lens element L7 are concave at the paraxial region. Further, the image-side surface S12 of the sixth lens L6 is cemented with the object-side surface S13 of the seventh lens L7.

In the fourth embodiment, the focal length f =3.76mm of the optical lens 100, the maximum field angle FOV =173.6deg of the optical lens 100, and the f-number FNO =1.8 of the optical lens 100 are taken as examples.

Other parameters in the fourth embodiment are given in the following table 7, and the definitions of the parameters can be obtained from the foregoing description, which is not repeated herein. It is understood that the units of the radius Y, thickness, and focal length in table 7 are mm. In table 7, the reference wavelength of the focal length of each lens is 546.00nm, and the reference wavelengths of the refractive index and abbe number of each lens are 587.60nm.

TABLE 7

In the fourth embodiment, table 8 gives the high-order term coefficients of each aspherical mirror surface usable in the third lens L3, the fifth lens L5, and the eighth lens L8 in the fourth embodiment, wherein each aspherical mirror surface type can be defined by the formula given in the first embodiment.

TABLE 8

Referring to fig. 8, fig. 8 shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of the optical lens 100 according to the fourth embodiment, and specific definitions are described with reference to the first embodiment and will not be repeated herein. As can be seen from fig. 8 (a), the spherical aberration value of the optical lens 100 in the fourth embodiment is better, which indicates that the imaging quality of the optical lens 100 in this embodiment is better. As can be seen from (B) in fig. 8, astigmatism of the optical lens 100 is well compensated at a wavelength of 546.00 nm. As can be seen from (C) in fig. 8, the distortion of the optical lens 100 is well corrected at a wavelength of 546.00 nm.

Fifth embodiment

Fig. 9 is a schematic structural diagram of an optical lens 100 according to a fifth embodiment of the present application. The optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop 102, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a filter L9, which are disposed in order from an object side to an image side along an optical axis O. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive refractive power, the seventh lens element L7 with negative refractive power, and the eighth lens element L8 with positive refractive power. As for 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, reference may be made to the above detailed description, and details thereof are not repeated here.

Further, in the fifth embodiment, the surface shape of each lens is different from that of each lens in the first embodiment in that: the image-side surface S12 of the sixth lens element L6 is convex at the paraxial region, and the object-side surface S13 of the seventh lens element L7 and the image-side surface S14 of the seventh lens element L7 are concave at the paraxial region. Further, the image-side surface S12 of the sixth lens L6 is cemented with the object-side surface S13 of the seventh lens L7.

In the fifth embodiment, the focal length f =4.01mm of the optical lens 100, the maximum field angle FOV =171deg of the optical lens 100, and the f-number FNO =1.75 of the optical lens 100 are taken as examples.

The other parameters in the fifth embodiment are shown in the following table 9, and the definitions of the parameters can be obtained from the foregoing description, which is not repeated herein. It is understood that the units of the radius Y, thickness, and focal length in table 9 are mm. In Table 9, the reference wavelength of the focal length of each lens is 546.00nm, and the reference wavelengths of the refractive index and Abbe number of each lens are 587.60nm.

TABLE 9

In the fifth embodiment, table 10 gives high-order term coefficients of respective aspherical mirror surfaces usable in the third lens L3, the fourth lens L4, and the eighth lens L8 in the fifth embodiment, wherein the respective aspherical mirror surfaces can be defined by the formulas given in the first embodiment.

TABLE 10

Referring to fig. 10, fig. 10 shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of the optical lens 100 according to the fifth embodiment, and specific definitions are described in the first embodiment and will not be repeated herein. As can be seen from fig. 10 (a), the spherical aberration value of the optical lens 100 in the fifth embodiment is better, which indicates that the imaging quality of the optical lens 100 in this embodiment is better. As can be seen from (B) in fig. 10, astigmatism of the optical lens 100 is well compensated at a wavelength of 546.00 nm. As can be seen from (C) in fig. 10, the distortion of the optical lens 100 is well corrected at a wavelength of 546.00 nm.

Referring to table 11, table 11 summarizes ratios of the relations in the first embodiment to the fifth embodiment of the present application.

TABLE 11

Referring to fig. 11, the present application further discloses a camera module 200, which includes a photo sensor 201 and the optical lens 100 according to any of the first to fifth embodiments, wherein the photo sensor 201 is disposed at an image side of the optical lens 100. The optical lens 100 may be configured to receive a light signal of a subject and project the light signal to the light sensing chip 201, and the light sensing chip 201 may be configured to convert the light signal corresponding to the subject into an image signal. And will not be described in detail herein. It can be understood that the camera module 200 having the optical lens 100 can improve the imaging quality of the optical lens 100, achieve the high-pixel shooting effect, and enable the optical lens 100 to have the characteristics of a large aperture and a large wide angle while realizing the miniaturization design. Since the above technical effects have been described in detail in the embodiments of the optical lens 100, they are not described herein again.

Referring to fig. 12, the present application further discloses an intelligent terminal, where the intelligent terminal 300 includes a terminal main body 301 and the camera module 200 as described above, and the camera module 200 is disposed on the terminal main body 301 to obtain image information. The smart terminal 300 may be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a smart watch, a monitor, an automobile, or the like. It can be understood that the smart terminal 300 having the camera module 200 also has all the technical effects of the optical lens 100. That is, the intelligent terminal 300 can improve the imaging quality of the optical lens 100, achieve the shooting effect of high pixels, and enable the optical lens 100 to have the characteristics of a large aperture and a large wide angle while realizing the miniaturization design. Since the above technical effects have been described in detail in the embodiments of the optical lens assembly 100, the detailed description thereof is omitted here.

The optical lens, the camera module and the intelligent terminal disclosed by the embodiment of the invention are described in detail, a specific example is applied in the description to explain the principle and the implementation mode of the invention, and the description of the embodiment is only used for helping to understand the optical lens, the camera module and the intelligent terminal and the core idea thereof; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. An optical lens is characterized in that the optical lens comprises eight lenses, and the eight lenses are 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 in sequence from an object side to an image side along an optical axis;

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

the third lens element with refractive power;

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

the seventh lens element with refractive power;

the optical lens satisfies the following relational expression:

3<CT4/SAGs7<11；

wherein CT4 is the thickness of the fourth lens on the optical axis, SAGs7 is the sagittal height of the object side surface of the fourth lens at the maximum effective semi-aperture.

2. An optical lens according to claim 1, characterized in that the optical lens satisfies the following relation:

2.5 sj f5/f <5; and/or

-9.1<f67/f<-3.5；

Wherein f5 is a focal length of the fifth lens element, f is a focal length of the optical lens, and f67 is a combined focal length of the sixth lens element and the seventh lens element.

3. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

1.5<CT3/CT2<4；

wherein CT2 is the thickness of the second lens element on the optical axis, and CT3 is the thickness of the third lens element on the optical axis.

4. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

9<TTL/f<11；

wherein, TTL is a distance on an optical axis from an object-side surface of the first lens element to an imaging surface of the optical lens, and f is a focal length of the optical lens.

5. An optical lens according to claim 1, characterized in that the optical lens satisfies the following relation:

4.5<f8/CT8<14.6；

wherein f8 is a focal length of the eighth lens element, and CT8 is a thickness of the eighth lens element on the optical axis.

6. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

8-Ap FOV/CRA <9; and/or

1.5<f/EPD<1.85；

The FOV is the maximum field angle of the optical lens, the CRA is the chief ray incident angle of the optical lens, f is the focal length of the optical lens, and the EPD is the entrance pupil diameter of the optical lens.

7. An optical lens according to claim 1, characterized in that the optical lens satisfies the following relation:

50deg<(FOV*f)/Y<60deg；

the FOV is the maximum field angle of the optical lens, f is the focal length of the optical lens, and Y is the diameter of the maximum effective imaging circle on the imaging surface of the optical lens.

8. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

1.55≤TTL/(Y/2)<1.65；

wherein, TTL is a distance on an optical axis from an object side surface of the first lens element to an imaging surface of the optical lens, and Y is a diameter of a maximum effective imaging circle on the imaging surface of the optical lens.

9. A camera module, comprising a photo sensor chip and the optical lens of any one of claims 1-8, wherein the photo sensor chip is disposed on an image side of the optical lens.

10. An intelligent terminal, characterized in that, intelligent terminal includes terminal main part and the module of making a video recording of claim 9, the module of making a video recording is located the terminal main part.