CN115166941A

CN115166941A - Optical lens, camera module and electronic equipment

Info

Publication number: CN115166941A
Application number: CN202210806529.7A
Authority: CN
Inventors: 谭怡翔; 党绪文
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2022-07-08
Filing date: 2022-07-08
Publication date: 2022-10-11
Anticipated expiration: 2042-07-08
Also published as: CN115166941B

Abstract

The invention discloses an optical lens, a camera module and an electronic device, wherein the optical lens comprises the following components which are arranged from an object side to an image side along an optical axis in sequence: the first lens element with negative refractive power has a convex object-side surface and a concave image-side surface at paraxial region, and a concave object-side surface at a paraxial region; a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface at paraxial region, respectively; a third lens element with negative refractive power; a fourth lens element with positive refractive power having a convex object-side surface and a concave image-side surface at paraxial region, respectively; a fifth lens element with positive refractive power having a convex object-side surface and a concave image-side surface at paraxial region, respectively; the optical lens satisfies the relation: 0.9 sP/EPD <1.3. The optical lens, the camera module and the electronic equipment provided by the invention can ensure the imaging quality and have the characteristics of large aperture and miniaturization.

Description

Optical lens, camera module and electronic equipment

Technical Field

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

Background

With the progress and development of society, people have higher and higher requirements on the imaging capability of electronic equipment, and large-aperture lenses are widely applied to electronic equipment because of having larger light transmission amount and being capable of adapting to the shooting condition of dark light.

Disclosure of Invention

The embodiment of the invention discloses an optical lens, a camera module and electronic equipment, which can ensure the imaging quality and have the characteristics of large aperture and miniaturization.

In order to achieve the above object, a first aspect of the present invention discloses an optical lens assembly, which includes five lens elements with refractive power, in order from an object side to an image side along an optical axis:

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

a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface;

a third lens element with negative refractive power;

a fourth lens element with positive refractive power having a convex object-side surface and a concave image-side surface;

a fifth lens element with positive refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region;

the optical lens satisfies the following relation:

0.9<f/EPD<1.3；

wherein f is the focal length of the optical lens, and EPD is the entrance pupil diameter of the optical lens.

The first lens of the optical lens is limited to have negative refractive power, and the object side surface and the image side surface of the first lens are respectively provided with the convex surface and the concave surface at the paraxial region, so that incident light rays with a larger angle can enter the optical lens, the field angle range of the optical lens is enlarged, and the incident light rays can be effectively converged, thereby being beneficial to controlling the size of the first lens in the direction vertical to the optical axis, ensuring that the first lens has a smaller caliber, and meeting the requirement of the miniaturization design of the optical lens; in addition, the concave surface of the object-side surface of the first lens element near the circumference is favorable for reducing the incident angle of the incident light with large angle and reducing the risk of astigmatism generated at the object-side end, so as to reduce the pressure of the image-side lens elements (i.e., the second lens element to the fifth lens element) for eliminating aberration; the second lens with negative refractive power is combined, and the object side surface and the image side surface of the second lens are respectively provided with a convex surface and a concave surface at the position close to the optical axis, so that the surface shapes of the second lens and the first lens can be more matched, the incident light is in smooth transition, the off-axis aberration can be corrected, the tolerance sensitivity of the optical lens can be reduced, meanwhile, the reasonable configuration of an air gap between the front lens and the rear lens can be facilitated, the risk of generating ghost images can be reduced, and the imaging quality of the optical lens can be improved; the first lens element to the third lens element can have negative and positive refractive power distribution by combining the third lens element with negative refractive power, which is beneficial to correcting spherical aberration and coma aberration of the optical lens and improving the imaging quality of the optical lens; the fourth lens has positive refractive power, and the object side surface and the image side surface of the fourth lens are respectively provided with a convex surface and a concave surface at the paraxial region, so that marginal field light can be effectively converged, the deflection of the marginal field light is reduced, marginal field aberration generated when the incident light passes through the first lens and the third lens is corrected, spherical aberration and coma aberration generated when the light is diffused through the third lens are corrected, the imaging quality of the optical lens is improved, and meanwhile, the total length of the optical lens can be shortened, so that the optical lens is beneficial to miniaturization; the fifth lens element with positive refractive power has a convex surface and a concave surface at a paraxial region, so that the fifth lens element has a height-matching surface profile with the fourth lens element, thereby reducing tolerance sensitivity of the optical lens assembly, further balancing the aberration generated by the front lens group (the first lens element to the fourth lens element) and difficult to correct, and promoting aberration balance of the optical lens assembly, thereby improving imaging quality of the optical lens assembly.

In addition, the optical lens satisfies 0.9 Ap/EPD <1.3, the ratio of the focal length to the entrance pupil diameter of the optical lens is limited, the light incoming amount of the optical lens can be effectively increased, the relative illumination of the optical lens is improved, the optical lens has the characteristic of a large aperture, the optical lens can adapt to the shooting condition of dim light, the generation of a dark angle is reduced, meanwhile, the size of an Airy spot can be reduced, the image resolving power of the optical lens is improved, the imaging quality of the optical lens is improved, and the design requirement of high pixels is met.

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

1.9 but less than TTL/IMGH <2.2; and/or, 0.11 are constructed with BFL/TTL <0.17;

wherein, TTL is a distance between an object side surface of the first lens element and an imaging surface of the optical lens along the optical axis (i.e., a total length of the optical lens), IMGH is a radius of a maximum effective imaging circle of the optical lens (i.e., an image height of the optical lens), and BFL is a minimum distance between an image side surface of the fifth lens element and the imaging surface of the optical lens along a direction parallel to the optical axis (i.e., a back focus of the optical lens).

The total size of the optical lens can be effectively shortened by restricting the ratio of the total length to the image height of the optical lens, so that the optical lens can have the characteristic of a large image surface while obtaining a smaller size, and the imaging quality of the optical lens can be improved. When the ratio is lower than the lower limit, the total length of the optical lens is too small, and the air gaps among the lenses are small, so that the sensitivity among the lenses is increased, and the design and the assembly of the lenses are not facilitated; when the ratio is higher than the upper limit, the total length of the optical lens is too large, which is not favorable for the miniaturization design of the optical lens.

In addition, through the specific value of the back focal and the total length of restriction optical lens, can rationally dispose the back focal and the total length of optical lens and account for the ratio to make light have sufficient distance and assemble to the imaging surface, thereby can make optical lens when satisfying the miniaturization, the chief ray incident angle on outermost visual field to the imaging surface of effective control, in order to reduce the chief ray incident angle of imaging surface, improve optical lens's relative illuminance, and then improve optical lens's imaging quality.

-0.5 yarn woven fabric of f2/f1<0, and-0.4 yarn woven fabric of f2/f3<0;

wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

Through restricting the ratio of the focal lengths of the second lens and the first lens and the ratio of the focal lengths of the second lens and the third lens, the refractive power of the first lens to the third lens can keep a certain difference, on one hand, the incident light converged by the first lens can be smoothly transited to the rear lens group (namely, the fourth lens and the fifth lens), and on the other hand, the rear lens group can be favorably balanced in spherical aberration and coma aberration, so that the imaging quality of the optical lens is improved. When the ratio of the first lens to the third lens is lower than the lower limit or higher than the upper limit, the aberration generated by the first lens to the third lens cannot be eliminated in a mutual cooperation mode, and meanwhile, incident light rays are too gathered or cannot be reasonably diffused, so that great pressure is generated on light ray control of the rear lens group, the fourth lens and the fifth lens are too bent, and the imaging quality of the optical lens is affected.

0.8 yarn-woven fabric (CT2/CT 3) is less than 1.9, and-0.4 yarn-woven fabric (f2/f 3) is less than 0;

wherein CT2 is the thickness of the second lens element on the optical axis (i.e., the central thickness of the second lens element), CT3 is the thickness of the third lens element on the optical axis (i.e., the central thickness of the third lens element), f2 is the focal length of the second lens element, and f3 is the focal length of the third lens element.

Through the ratio of the central thickness of the second lens and the central thickness of the third lens which are reasonably controlled, the central thickness of the second lens is closer to that of the third lens, so that light can be smoothly transited, chromatic aberration and spherical aberration of the optical lens can be corrected, and the imaging quality of the optical lens is improved.

By combining with the control of the ratio of the focal lengths of the second lens element and the third lens element, the refractive powers of the second lens element and the third lens element can be reasonably configured to properly adjust the deflection angle and the tendency of the light, thereby further improving the imaging quality of the optical lens.

1.9< ∑ CT/Σ AT <5, and-0.4</f 2/f3<0;

Σ CT is the sum of the thicknesses of the first to fifth lenses on the optical axis (i.e., the sum of the center thicknesses of the lenses of the optical lens), Σ AT is the sum of the air gaps of the first to fifth lenses on the optical axis (i.e., the sum of the air gaps of the lenses of the optical lens), f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

The optical lens has the advantages that the ratio of the sum of the central thicknesses of the lenses of the optical lens to the sum of the air gaps is restrained, the structural compactness of the optical lens can be improved, the miniaturization of the optical lens is facilitated, meanwhile, the air gaps among the lenses (the distance from the image side surface of the previous lens to the object side surface of the next lens) can be reasonably configured, so that on one hand, the uniform distribution of the lenses of the optical lens can be ensured, the smooth transition of light rays is facilitated, the aberration and the distortion of the optical lens are improved, the imaging quality of the optical lens is improved, on the other hand, the tolerance sensitivity of the optical lens can be reduced, the optical lens has good optical performance, and the imaging quality of the optical lens is further improved.

By combining with the control of the ratio of the focal lengths of the second lens element and the third lens element, the refractive powers of the second lens element and the third lens element can be configured reasonably, which is favorable for eliminating high-order aberration and improving the imaging quality of the optical lens.

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

-5-t f1/f34<0.5, and 1-t ct3/CT4<3;

wherein f1 is a focal length of the first lens element, f34 is a combined focal length of the third lens element and the fourth lens element, CT3 is a thickness of the third lens element on the optical axis (i.e., a central thickness of the third lens element), and CT4 is a thickness of the fourth lens element on the optical axis (i.e., a central thickness of the fourth lens element).

By restricting the ratio of the focal length of the first lens to the combined focal length of the third lens and the fourth lens, the first lens can be used for correcting coma aberration and field curvature generated when light enters the fourth lens from the third lens, so that the imaging quality of the optical lens is improved.

The constraint of the ratio of the center thicknesses of the third lens and the fourth lens is combined, the overlarge difference of the center thicknesses of the third lens and the fourth lens can be avoided, the gentle expansion of light rays in the third lens is facilitated, the light rays have enough travel when the propagation direction is corrected in the fourth lens, the chromatic aberration and the spherical aberration of the optical lens are corrected, and the imaging quality of the optical lens is improved.

0.5-woven SD11/IMGH <0.6, and 0<f/f5<1;

wherein SD11 is the maximum effective half aperture of the object-side surface of the first lens element, IMGH is the radius of the maximum effective imaging circle of the optical lens (i.e. the image height of the optical lens), and f5 is the focal length of the fifth lens element.

The ratio of the maximum effective half aperture of the object side surface of the first lens and the image height of the optical lens can be restrained, the segment difference between the lenses of the optical lens can be reduced, the smooth transition of light rays between the lenses of the optical lens is facilitated, meanwhile, the light transmission quantity of the optical lens can be increased, the relative illumination of the optical lens is improved, and the imaging quality of the optical lens is improved. When the ratio is lower than the lower limit or higher than the upper limit, the difficulty in controlling the incident light is increased, a long structure is needed to realize the smooth transition of the light, the miniaturization of the optical lens is not facilitated, and the relative illumination of the optical lens cannot be ensured, so that the imaging quality of the optical lens is reduced.

Meanwhile, by combining the control of the ratio of the focal length of the optical lens to the focal length of the fifth lens element, the refractive power of the fifth lens element can be reasonably configured, which is beneficial to balancing the aberration problem caused by the large aperture characteristics, so as to further improve the imaging quality of the optical lens.

SAG42/SAG51<3, and 0<f/f5<1;

SAG42 is the distance from the maximum effective aperture of the image side surface of the fourth lens to the intersection point of the image side surface of the fourth lens and the optical axis in the direction parallel to the optical axis (namely the rise of the vector at the maximum effective semi-aperture of the image side surface of the fourth lens), SAG51 is the distance from the maximum effective aperture of the object side surface of the fifth lens to the intersection point of the object side surface of the fifth lens and the optical axis in the direction parallel to the optical axis (namely the rise of the vector at the maximum effective semi-aperture of the object side surface of the fifth lens), and f5 is the focal length of the fifth lens.

The ratio of the rise of the maximum effective semi-aperture position of the image side surface of the fourth lens and the object side surface of the fifth lens is restrained, the bending degree of the image side surface of the fourth lens and the bending degree of the object side surface of the fifth lens can be effectively controlled, so that the image side surface of the fourth lens is matched with the object side surface of the fifth lens, the deflection angle of light rays is favorably reduced, the off-axis chromatic aberration is reduced, meanwhile, the light transmission amount of the fourth lens and the fifth lens can be improved, the relative illumination of the optical lens is improved, and the imaging quality of the optical lens is improved.

56deg<FOV/FNO<90deg；

wherein, the FOV is the field angle of the optical lens, and the FNO is the f-number of the optical lens;

by restricting the ratio of the field angle and the diaphragm number of the optical lens, the field angle of the optical lens can be limited while the large diaphragm characteristic of the optical lens is ensured, so that the incident angle of light rays can be reasonably controlled, smooth transition of the light rays is facilitated, and the imaging quality of the optical lens is improved. When the ratio is lower than the lower limit, the field angle of the optical lens is too small, so that the field range of the optical lens is reduced, and the acquisition of the optical lens to an object space is not facilitated, or the aperture of the optical lens is too small, so that the light flux of the optical lens is insufficient, so that the optical lens generates a dark angle, and the imaging quality of the optical lens is reduced; when the ratio is higher than the upper limit, the field angle of the optical lens is too large, so that the aperture of the optical lens is too large, which is not beneficial to controlling the light rays entering the optical lens, and the aberration and distortion which are difficult to correct are easy to generate, thereby reducing the imaging quality of the optical lens.

In a second aspect, the present invention discloses a camera module, which includes an image sensor and the optical lens of the first aspect, wherein the image sensor is disposed on the image side of the optical lens. The camera module with the optical lens has the characteristics of large aperture and miniaturization while ensuring the imaging quality.

In a third aspect, the present invention discloses an electronic device, which includes a housing and the camera module set according to the second aspect, wherein the camera module set is disposed on the housing. The electronic equipment with the camera module has the characteristics of large aperture and miniaturization while ensuring the imaging quality.

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

according to the optical lens, the camera module and the electronic device, the first lens of the optical lens has negative refractive power, and the object side surface and the image side surface of the first lens are respectively provided with the convex surface and the concave surface at the position of a paraxial region, so that incident light rays with a larger angle can enter the optical lens, the field angle range of the optical lens is enlarged, and meanwhile, the incident light rays can be effectively converged, thereby being beneficial to controlling the size of the first lens in the direction vertical to the optical axis, ensuring that the first lens has a smaller caliber, and meeting the miniaturization design of the optical lens; in addition, the concave surface of the object-side surface of the first lens element near the circumference is favorable for reducing the incident angle of the incident light with large angle and reducing the risk of astigmatism generated at the object-side end, so as to reduce the pressure of the image-side lens elements (i.e., the second lens element to the fifth lens element) for eliminating aberration; the second lens with negative refractive power is combined, and the object side surface and the image side surface of the second lens are respectively provided with a convex surface and a concave surface at the position close to the optical axis, so that the surface shapes of the second lens and the first lens can be more matched, the incident light rays are smoothly transited, the off-axis aberration can be corrected, the tolerance sensitivity of the optical lens can be reduced, meanwhile, the air gap between the front lens and the rear lens can be reasonably configured, the risk of generating ghost images can be reduced, and the imaging quality of the optical lens can be improved; the first lens element to the third lens element can have negative and positive refractive power distribution by combining the third lens element with negative refractive power, which is beneficial to correcting spherical aberration and coma aberration of the optical lens and improving the imaging quality of the optical lens; the fourth lens has positive refractive power, and the object side surface and the image side surface of the fourth lens are respectively provided with a convex surface and a concave surface at a paraxial region, so that marginal field rays can be effectively converged, the deflection of the marginal field rays is reduced, the marginal field aberration generated when the incident rays pass through the first lens and the third lens is corrected, and the spherical aberration and the coma aberration generated when the rays are diffused by the third lens are corrected, so that the imaging quality of the optical lens is improved, and meanwhile, the total length of the optical lens can be shortened, and the miniaturization of the optical lens is facilitated; the fifth lens element with positive refractive power has a convex surface and a concave surface at a paraxial region, so that the fifth lens element has a height-matching surface profile with the fourth lens element, thereby reducing tolerance sensitivity of the optical lens assembly, further balancing the aberration generated by the front lens group (the first lens element to the fourth lens element) and difficult to correct, and promoting aberration balance of the optical lens assembly, thereby improving imaging quality of the optical lens assembly.

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 (mm), an astigmatism diagram (mm), and a distortion diagram (%);

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 (mm), an astigmatism diagram (mm), and a distortion diagram (%);

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

fig. 6 is a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%);

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 (mm), an astigmatism diagram (mm), and a distortion diagram (%);

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 (mm), an astigmatism diagram (mm), and a distortion diagram (%);

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

fig. 12 is a schematic structural diagram of an electronic device 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 derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within 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 an orientation or positional relationship based on the orientation or positional relationship 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 by those skilled in the art as appropriate.

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 embodiments and the accompanying drawings.

Referring to fig. 1, according to a first aspect of the present application, an optical lens 100 is disclosed, in which the optical lens 100 includes five lens elements with refractive power, including a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5, which are sequentially disposed 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, and the fifth lens L5 in sequence from the object side of the first lens L1, and is finally imaged on the imaging surface 101 of the optical lens 100. The first lens element L1 has negative refractive power, the second lens element L2 has positive refractive power, the third lens element L3 has negative refractive power, the fourth lens element L4 has positive refractive power, and the fifth lens element L5 has positive refractive power.

Further, the object-side surface 11 of the first lens element L1 is convex at the paraxial region O, and the image-side surface 12 of the first lens element L1 is concave at the paraxial region O; the object-side surface 21 of the second lens element L2 is convex at the 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 concave or convex at the paraxial region O, and the image-side surface 32 of the third lens element L3 is concave or convex at the paraxial region O; the object-side surface 41 of the fourth lens element L4 is convex at the paraxial region O, and the image-side surface 42 of the fourth lens element L4 is concave at the paraxial region O; the object-side surface 51 of the fifth lens element L5 is convex at the paraxial region O, and the image-side surface 52 of the fifth lens element L5 is concave at the paraxial region O.

The object side surface 11 of the first lens element L1 is concave at the circumference, and the image side surface 12 of the first lens element L1 is convex at the circumference; the object-side surface 21 of the second lens element L2 is concave at the circumference, and the image-side surface 22 of the second lens element L2 is convex at the circumference; the object-side surface 31 of the third lens element L3 is concave at the circumference, and the image-side surface 32 of the third lens element L3 is convex at the circumference; the object-side surface 41 of the fourth lens element L4 is concave at the circumference, and the image-side surface 42 of the fourth lens element L4 is convex at the circumference; the object-side surface 51 of the fifth lens element L5 is concave at the circumference, and the image-side surface 52 of the fifth lens element L5 is convex at the circumference.

By properly arranging the surface shapes and refractive powers of the lenses between the first lens element L1 and the fifth lens element L5, the optical lens system 100 can have a large aperture and a small size while ensuring the imaging quality.

Further, in some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are all made of plastic, and in this case, the optical lens 100 can reduce the weight and the cost. In other embodiments, the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5 may also be made of glass, so that the optical lens 100 has a good optical effect, and the temperature drift sensitivity of the optical lens 100 may also be reduced.

In some embodiments, for convenience of processing and molding, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 may all be aspheric lenses. It is to be understood that in other embodiments, spherical lenses may be used for the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5.

In some embodiments, the optical lens 100 further includes a stop STO, which may be an aperture stop and/or a field stop, for example, the stop STO may be an aperture stop, or the stop STO may be a field stop, or the stop STO may be an aperture stop and a field stop. By providing the stop STO on the object side of the first lens L1, the exit pupil can be made distant from the imaging surface 101, and the effective diameter of the optical lens 100 can be reduced without reducing the telecentricity of the optical lens 100, thereby achieving downsizing. It is understood that in other embodiments, the stop STO can be disposed between other lenses, and the arrangement is adjusted according to the actual situation, which is not specifically limited in this embodiment.

In some embodiments, the optical lens 100 further includes an infrared band-pass filter 60, and the infrared band-pass filter 60 is disposed between the fifth lens element L5 and the image plane 101 of the optical lens 100. Select for use infrared band pass filter 60, can see through the infrared light to the reflection visible light, in order to realize optical lens 100's infrared imaging, make optical lens 100 can be adapted to dark light shooting environment such as rainy day, night.

It is understood that the infrared band pass filter 60 may be made of an optical glass coating, a colored glass, or an infrared band pass filter 60 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:

0.9<f/EPD<1.3；

where f is the focal length of the optical lens 100, and EPD is the entrance pupil diameter of the optical lens 100.

By limiting the first lens element L1 of the optical lens 100 to have negative refractive power, and combining the arrangement that the object-side surface 11 and the image-side surface 12 of the first lens element L1 are respectively convex and concave at the paraxial region O, the incident light with a larger angle can enter the optical lens 100, so as to expand the field angle range of the optical lens 100, and the incident light can be effectively converged, thereby facilitating the control of the size of the first lens element L1 in the direction perpendicular to the paraxial region O, and ensuring that the first lens element L1 has a smaller caliber to meet the miniaturization design of the optical lens 100; in addition, the concave surface of the object-side surface 11 of the first lens element L1 near the circumference is favorable for reducing the incident angle of the incident light with large angle and reducing the risk of astigmatism generated at the object-side end, so as to reduce the pressure of the image-side lens elements (i.e., the second lens element L2 to the fifth lens element L5) for eliminating the aberration; by combining the second lens element L2 with negative refractive power, the object-side surface 21 and the image-side surface 22 of the second lens element L2 are respectively convex and concave at the paraxial region O, so that the surface shapes of the second lens element L2 and the first lens element L1 can be better matched, incident light rays can be smoothly transited, off-axis aberration can be corrected, tolerance sensitivity of the optical lens 100 can be reduced, and meanwhile, an air gap between the front and rear lens elements can be reasonably configured to reduce the risk of generating ghost images, thereby improving the imaging quality of the optical lens 100; by combining the third lens element L3 with negative refractive power, the first lens element L1 to the third lens element L3 can have negative and positive refractive power distribution, which is beneficial to correcting spherical aberration and coma aberration of the optical lens 100 and improving the imaging quality of the optical lens 100; the fourth lens element L4 has positive refractive power, and the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are respectively disposed on the paraxial region O as a convex surface and a concave surface, so that peripheral field rays can be effectively converged, and deflection of the peripheral field rays can be reduced, so as to correct peripheral field aberrations generated when incident rays pass through the first lens element L1 to the third lens element L3, and spherical aberration and coma aberration generated when the rays are diffused through the third lens element L3 can be corrected, thereby improving the imaging quality of the optical lens 100, and simultaneously shortening the total length of the optical lens 100, so as to facilitate miniaturization of the optical lens 100; the fifth lens element L5 has positive refractive power, and the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are respectively convex and concave at the paraxial region O, so that the surface shapes of the fifth lens element L5 and the fourth lens element L4 can be highly matched, the tolerance sensitivity of the optical lens assembly 100 can be reduced, the aberrations generated by the front lens group (the first lens element L1 to the fourth lens element L4) which are difficult to correct can be further balanced, the aberration balance of the optical lens assembly 100 can be promoted, and the imaging quality of the optical lens assembly 100 can be improved, meanwhile, the image-side surface 52 of the fifth lens element L5 is concave at the paraxial region O, and the imaging range of the optical lens assembly 100 can be ensured, and the outer diameter of the fifth lens element L5 can be prevented from being too large, thereby realizing the miniaturization of the optical lens assembly 100.

In addition, the optical lens 100 satisfies 0.9-Ap f/EPD <1.3, by limiting the ratio of the focal length to the entrance pupil diameter of the optical lens 100, the light entering amount of the optical lens 100 can be effectively increased, the relative illumination of the optical lens 100 is improved, the optical lens 100 has the characteristic of a large aperture, so that the optical lens 100 can adapt to the shooting condition of dark light, the generation of a dark angle is reduced, meanwhile, the size of an Airy-Sharpus can be reduced, the resolving power of the optical lens 100 is improved, and the imaging quality of the optical lens 100 is improved, so as to satisfy the design requirement of high pixels.

In some embodiments, the optical lens 100 satisfies the following relationship:

1.9 & lt ttl/IMGH <2.2; and/or, 0.11 is formed by the woven fabric with BFL/TTL less than 0.17;

wherein, TTL is a distance from the object-side surface 11 of the first lens element L1 to the image plane 101 of the optical lens system 100 on the optical axis O (i.e., a total length of the optical lens system 100), IMGH is a radius of a maximum effective imaging circle of the optical lens system 100 (i.e., an image height of the optical lens system 100), and BFL is a minimum distance from the image-side surface 52 of the fifth lens element L5 to the image plane 101 of the optical lens system 100 in a direction parallel to the optical axis O (i.e., a back focus of the optical lens system 100).

By restricting the ratio of the total length to the image height of the optical lens 100, the total size of the optical lens 100 can be effectively shortened, so that the optical lens 100 can have the characteristic of a large image plane while obtaining a smaller size, thereby being beneficial to improving the imaging quality of the optical lens 100. When the ratio is lower than the lower limit, the total length of the optical lens 100 is too small, and the air gap between the lenses is small, so that the sensitivity between the lenses is increased, which is not favorable for the design and assembly of the lenses, and meanwhile, the arrangement space of the optical lens 100 is insufficient, so that the surface shape of the lenses is excessively curved, thereby easily generating high-order aberration, being unfavorable for the aberration balance of the optical lens 100, and further causing the imaging quality of the optical lens 100 to be reduced; when the ratio is higher than the upper limit, the total length of the optical lens 100 is too large, which is disadvantageous for the miniaturized design of the optical lens 100.

In addition, through the specific value of the back focal length and the total length of the optical lens 100, the occupation ratio of the back focal length and the total length of the optical lens 100 can be reasonably configured, so that light rays have enough distance to converge to the imaging surface 101, thereby being capable of effectively controlling the incident angle of the chief ray on the outermost visual field to the imaging surface 101 while the optical lens 100 is miniaturized, so as to reduce the incident angle of the chief ray of the imaging surface 101, improve the relative illumination of the optical lens 100, and further improve the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

-0.5 yarn woven fabric of f2/f1<0, and-0.4 yarn woven fabric of f2/f3<0;

wherein f1 is the focal length of the first lens L1, f2 is the focal length of the second lens L2, and f3 is the focal length of the third lens L3.

Through the ratio of the focal length of constraining second lens L2 and first lens L1, and the ratio of the focal length of second lens L2 and third lens L3, can make the refractive power of first lens L1 to third lens L3 keep certain disparity, on the one hand can be favorable to the incident light smooth transition that assembles through first lens L1 to back lens group (fourth lens L4 and fifth lens L5 promptly), on the other hand, can also be favorable to balanced spherical aberration and coma of back lens group, in order to improve optical lens 100's imaging quality. When the ratio is lower than the lower limit or higher than the upper limit, the aberrations generated by the first lens L1 to the third lens L3 cannot be cooperatively eliminated, and meanwhile, the incident light rays are too gathered or not reasonably diffused, so that great pressure is generated for controlling the light rays of the rear lens group, and the fourth lens L4 and the fifth lens L5 are too bent, thereby affecting the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

wherein, CT2 is the thickness of the second lens element L2 on the optical axis O (i.e. the central thickness of the second lens element L2), CT3 is the thickness of the third lens element L3 on the optical axis O (i.e. the central thickness of the third lens element L3), f2 is the focal length of the second lens element L2, and f3 is the focal length of the third lens element L3.

Through the ratio of the central thickness of the second lens L2 and the third lens L3 which are reasonably controlled, the central thickness of the second lens L2 and the central thickness of the third lens L3 are relatively close to each other, so that light can be smoothly transited, the chromatic aberration and the spherical aberration of the optical lens 100 can be corrected, and the imaging quality of the optical lens 100 can be improved.

By combining with the control of the ratio of the focal lengths of the second lens element L2 and the third lens element L3, the refractive powers of the second lens element L2 and the third lens element L3 can be configured reasonably to adjust the deflection angle and the trend of the light beam appropriately, thereby further improving the imaging quality of the optical lens system 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

1.9< ∑ CT/Σ AT <5, and-0.4 < -f 2/f3<0;

Σ CT is the sum of the thicknesses of the first lens L1 to the fifth lens L5 on the optical axis O (i.e., the sum of the central thicknesses of the lenses of the optical lens 100), Σ AT is the sum of the air gaps of the first lens L1 to the fifth lens L5 on the optical axis O (i.e., the sum of the air gaps of the lenses of the optical lens 100), f2 is the focal length of the second lens L2, and f3 is the focal length of the third lens L3.

By restricting the ratio of the sum of the central thicknesses of the lenses of the optical lens 100 to the sum of the air gaps, the structural compactness of the optical lens 100 can be improved, which is beneficial to the miniaturization of the optical lens 100, and simultaneously, the air gaps between the lenses (the distance from the image side surface of the previous lens to the object side surface of the next lens) can be reasonably configured, so that on one hand, the uniform distribution of the lenses of the optical lens 100 can be ensured, the smooth transition of light rays is facilitated, the aberration and distortion of the optical lens 100 are improved, so as to improve the imaging quality of the optical lens 100, and on the other hand, the tolerance of the optical lens 100 can be reduced, so that the optical lens 100 has good optical performance, and the imaging quality of the optical lens 100 is further improved.

By controlling the ratio of the focal lengths of the second lens element L2 and the third lens element L3, the refractive powers of the second lens element L2 and the third lens element L3 can be configured reasonably, which is beneficial to eliminating high-order aberrations and improving the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

-5< -f1/f 34<0.5, and 1< -CT3/CT 4<3;

where f1 is a focal length of the first lens element L1, f34 is a combined focal length of the third lens element L3 and the fourth lens element L4, CT3 is a thickness of the third lens element L3 on the optical axis O (i.e., a central thickness of the third lens element L3), and CT4 is a thickness of the fourth lens element L4 on the optical axis O (i.e., a central thickness of the fourth lens element L4).

By restricting the ratio of the focal length of the first lens L1 to the combined focal length of the third lens L3 and the fourth lens L4, the first lens L1 can be used to correct the coma aberration and the field curvature generated when the light enters the fourth lens L4 from the third lens L3, so as to improve the imaging quality of the optical lens 100.

By combining the constraint on the ratio of the central thicknesses of the third lens L3 and the fourth lens L4, the difference between the central thicknesses of the third lens L3 and the fourth lens L4 can be avoided being too large, which is beneficial to the gentle expansion of the light rays in the third lens L3, and the light rays have enough travel when the propagation direction is corrected in the fourth lens L4, so that the chromatic aberration and the spherical aberration of the optical lens 100 can be corrected, and the imaging quality of the optical lens 100 can be improved.

In some embodiments, the optical lens 100 satisfies the following relationship:

0.5< -SD11/IMGH <0.6, and 0<f/f5<1;

where SD11 is the maximum effective half aperture of the object-side surface 11 of the first lens L1, IMGH is the radius of the maximum effective imaging circle of the optical lens 100 (i.e. the image height of the optical lens 100), and f5 is the focal length of the fifth lens L5.

By restricting the ratio of the maximum effective half aperture of the object side surface 11 of the first lens L1 to the image height of the optical lens 100, the step difference between the lenses of the optical lens 100 can be reduced, which is beneficial to the smooth transition of light between the lenses of the optical lens 100, and meanwhile, the light flux of the optical lens 100 can be increased, the relative illumination of the optical lens 100 is improved, and the imaging quality of the optical lens 100 is improved. When the ratio is lower than the lower limit or higher than the upper limit, the difficulty in controlling the incident light is increased, a long structure is required to realize smooth transition of the light, which is not favorable for miniaturization of the optical lens 100, and relative illumination of the optical lens 100 cannot be ensured, resulting in a decrease in the imaging quality of the optical lens 100.

Meanwhile, by controlling the ratio of the focal length of the optical lens 100 to the focal length of the fifth lens element L5, the refractive power of the fifth lens element L5 can be configured reasonably, which is beneficial to balancing the aberration problem caused by the large aperture characteristics, so as to further improve the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

SAG42/SAG51<3, and 0<f/f5<1;

here, SAG42 is a distance in a direction parallel to the optical axis O from a maximum effective aperture of the image-side surface 42 of the fourth lens L4 to an intersection point of the image-side surface 42 of the fourth lens L4 and the optical axis O (i.e., a rise of a vector at a maximum effective half aperture of the image-side surface 42 of the fourth lens L4), SAG51 is a distance in a direction parallel to the optical axis O from a maximum effective aperture of the object-side surface 51 of the fifth lens L5 to an intersection point of the object-side surface 51 of the fifth lens L5 and the optical axis O (i.e., a rise of a vector at a maximum effective half aperture of the object-side surface 51 of the fifth lens L5), and f5 is a focal length of the fifth lens L5.

By restricting the ratio of the rise at the maximum effective half aperture of the image-side surface 42 of the fourth lens L4 and the object-side surface 51 of the fifth lens L5, the bending degree of the image-side surface 42 of the fourth lens L4 and the bending degree of the object-side surface 51 of the fifth lens L5 can be effectively controlled, so that the image-side surface 42 of the fourth lens L4 and the object-side surface 51 of the fifth lens L5 are more matched, which is beneficial to reducing the deflection angle of light, reducing the off-axis chromatic aberration, and simultaneously, the light transmission amount of the fourth lens L4 and the fifth lens L5 can be improved, so as to improve the relative illumination of the optical lens 100, thereby improving the imaging quality of the optical lens 100.

Meanwhile, by combining the constraint on the ratio of the focal length of the optical lens 100 to the focal length of the fifth lens element L5, the refractive power of the fifth lens element L5 can be configured reasonably, which is beneficial to balancing the aberration problem caused by the large aperture characteristics, so as to further improve the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

56deg<FOV/FNO<90deg；

wherein, FOV is the field angle of the optical lens 100, and FNO is the f-number of the optical lens 100;

by restricting the ratio of the field angle to the f-number of the optical lens 100, the field angle of the optical lens 100 can be limited while ensuring the large aperture characteristic of the optical lens 100, so as to reasonably control the incident angle of light, thereby facilitating the realization of smooth transition of light and improving the imaging quality of the optical lens 100. When the ratio is lower than the lower limit, the field angle of the optical lens 100 is too small, which results in a reduction of the field range of the optical lens 100 and is not favorable for the optical lens 100 to acquire the object space, or the aperture of the optical lens 100 is too small and the light flux of the optical lens 100 is insufficient, which causes the optical lens 100 to generate a dark angle and results in a reduction of the imaging quality of the optical lens 100; when the ratio is higher than the upper limit, the field angle of the optical lens 100 is too large, so that the aperture of the optical lens 100 is too large, which is not favorable for controlling the light entering the optical lens 100, and is liable to generate aberration and distortion which are difficult to correct, thereby reducing the imaging quality of the optical lens 100.

In addition, the object-side surface and the image-side surface of any one of the first lens L1 to the fifth lens L5 are aspheric, and the surface shape of each aspheric lens can be defined by, but is not limited to, the following aspheric formula:

where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the surface vertex, r is the distance from any point on the aspheric surface to the optical axis, c is the curvature of the aspheric vertex, c =1/Y, Y is the radius of curvature (i.e., paraxial curvature c is the reciprocal of the radius of Y in table 1), k is the conic constant, and Ai is the coefficient corresponding to the higher order term in the aspheric surface type formula.

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

First embodiment

Fig. 1 shows a schematic structural diagram of an optical lens 100 disclosed in the first embodiment of the present application, where the optical lens 100 includes a stop STO, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an infrared band-pass filter 60, which are sequentially disposed from an object side to an image side along an optical axis O. For materials of the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, the first lens element L1 has negative refractive power, the second lens element L2 has positive refractive power, the third lens element L3 has negative refractive power, the fourth lens element L4 has positive refractive power, and the fifth lens element L5 has positive refractive power.

Further, the object-side surface 11 and the image-side surface 12 of the first lens element L1 are respectively convex and concave at the paraxial region O; the object-side surface 21 and the image-side surface 22 of the second lens element L2 are respectively convex and concave at the paraxial region O; 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; the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are respectively convex and concave at the paraxial region O; the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are convex and concave, respectively, at the paraxial region O.

The object-side surface 11 and the image-side surface 12 of the first lens element L1 are respectively concave and convex at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens element L2 are respectively concave and convex at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens element L3 are respectively concave and convex at the circumference, the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are respectively concave and convex at the circumference, 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 circumference.

Specifically, taking as an example the effective focal length f =2.04mm of the optical lens 100, the f-number FNO =1.07 of the optical lens 100, the field angle FOV =81.01deg of the optical lens 100, and the total length TTL =3.62mm of the optical lens 100, other parameters of the optical lens 100 are given in table 1 below. The elements from the object side to the image side along the optical axis O of the optical lens 100 are sequentially 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 2 and 3 correspond to the object side surface and the image side surface of the first lens L1, respectively. The Y radius in table 1 is the curvature radius of the object-side surface or the image-side surface of the corresponding surface number at the optical axis O. The first value in the "thickness" parameter list of a 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 STO in the "thickness" parameter column is the distance from the stop STO to the vertex of the next surface (the vertex refers to the intersection point of the surface and the optical axis O) on 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 STO is disposed on the image side of the vertex of the next surface, and if the thickness of the stop STO is a positive value, the stop STO is disposed on the object side of the vertex of the next surface. It is understood that the units of the radius Y, the thickness and the focal length in table 1 are mm, and the refractive index and the abbe number in table 1 are obtained at the reference wavelength 587nm, and the focal length is obtained at the reference wavelength 920 nm.

K in table 2 is a conic constant, and table 2 gives coefficients of high-order terms A4, A6, A8, a10, a12, a14, a16, a18, and a20 that can be used for each aspherical mirror surface in the first embodiment.

TABLE 1

TABLE 2

Referring to fig. 2 (a), fig. 2 (a) shows a longitudinal spherical aberration diagram of the optical lens 100 in the first embodiment at a wavelength of 587 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 illustrates 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 587 nm. Wherein the abscissa along the X-axis direction represents the focus offset and the ordinate along the Y-axis direction represents the image height in mm. 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 at this wavelength.

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 587 nm. 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 (C) in fig. 2, the distortion of the optical lens 100 is well corrected at this wavelength.

Second embodiment

A schematic structural diagram of an optical lens 100 disclosed in the second embodiment of the present application is shown in fig. 3, where the optical lens 100 includes a stop STO, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an infrared band-pass filter 60, which are sequentially disposed from an object side to an image side along an optical axis O. For materials of the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, the first lens element L1 with negative refractive power, the second lens element L2 with positive refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power and the fifth lens element L5 with positive refractive power are disposed in the lens element.

Specifically, the effective focal length f =2.35mm of the optical lens 100, the f-number FNO =1.03 of the optical lens 100, the field angle FOV =79.06deg of the optical lens 100, and the total length TTL =4.19mm of the optical lens 100 are taken as examples.

Other parameters in the second embodiment are given in table 3 below, 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, the thickness, and the focal length in table 3 are all mm, and the refractive index and the abbe number in table 3 are obtained at the reference wavelength 587nm, and the focal length is obtained at the reference wavelength 920 nm.

K in table 4 is a conic constant, and table 4 gives coefficients of high-order terms A4, A6, A8, a10, a12, a14, a16, a18, and a20 that can be used for each aspherical mirror surface in the second embodiment.

TABLE 3

TABLE 4

Referring to fig. 4, as can be seen from the longitudinal spherical aberration diagram (a) in fig. 4, the astigmatism diagram (B) in fig. 4, and the distortion diagram (C) in fig. 4, the longitudinal spherical aberration, the astigmatism, and the distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, as for the wavelengths corresponding to the curves in fig. 4 (a), fig. 4 (B), and fig. 4 (C), the contents described in the first embodiment with respect to fig. 2 (a), fig. 2 (B), and fig. 2 (C) may be referred to, and details thereof are not repeated herein.

Third embodiment

A schematic structural diagram of an optical lens 100 disclosed in the third embodiment of the present application is shown in fig. 5, where the optical lens 100 includes a stop STO, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an infrared band-pass filter 60, which are sequentially disposed from an object side to an image side along an optical axis O. For materials of the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5, reference may be made to the above-mentioned detailed description, and details thereof are not repeated herein.

Further, the object-side surface 11 and the image-side surface 12 of the first lens element L1 are respectively convex and concave at the paraxial region O; the object-side surface 21 and the image-side surface 22 of the second lens element L2 are respectively convex and concave at the paraxial region O; the object-side surface 31 and the image-side surface 32 of the third lens element L3 are both concave at the paraxial region O; the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are respectively convex and concave at the paraxial region O; the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are convex and concave, respectively, at the paraxial region O.

Specifically, the effective focal length f =2.49mm of the optical lens 100, the f-number FNO =1.09 of the optical lens 100, the field angle FOV =76.06deg of the optical lens 100, and the total length TTL =4.39mm of the optical lens 100 are taken as examples.

Other parameters in the third embodiment are given in table 5 below, and the definitions of the parameters can be obtained from the description of the previous embodiment, which is not repeated herein. It is understood that the units of the radius Y, the thickness, and the focal length in table 5 are mm, and the refractive index and the abbe number in table 5 are obtained at the reference wavelength 587nm, and the focal length is obtained at the reference wavelength 920 nm.

K in table 6 is a conic constant, and table 6 gives coefficients of high-order terms A4, A6, A8, a10, a12, a14, a16, a18, and a20 that can be used for each aspherical mirror surface in the third embodiment.

TABLE 5

TABLE 6

Referring to fig. 6, as can be seen from the longitudinal spherical aberration diagram (a) in fig. 6, the astigmatism diagram (B) in fig. 6, and the distortion diagram (C) in fig. 6, the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, as for the wavelengths corresponding to the curves in fig. 6 (a), fig. 6 (B), and fig. 6 (C), the contents described in the first embodiment with respect to fig. 2 (a), fig. 2 (B), and fig. 2 (C) may be referred to, and details thereof are not repeated herein.

Fourth embodiment

A schematic structural diagram of an optical lens 100 disclosed in the fourth embodiment of the present application is shown in fig. 7, where the optical lens 100 includes a stop STO, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an infrared band-pass filter 60, which are sequentially disposed from an object side to an image side along an optical axis O. For materials of the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

The object-side surface 11 and the image-side surface 12 of the first lens element L1 are concave and convex, respectively, at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens element L2 are concave and convex, respectively, at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens element L3 are concave and convex, respectively, at the circumference, the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are concave and convex, respectively, and the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are concave and convex, respectively, at the circumference.

Specifically, the effective focal length f =1.85mm of the optical lens 100, the f-number FNO =0.97 of the optical lens 100, the field angle FOV =86.35deg of the optical lens 100, and the total length TTL =3.58mm of the optical lens 100 are taken as examples.

Other parameters in the fourth embodiment are given in table 7 below, 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, the thickness, and the focal length in table 7 are mm, and the refractive index and the abbe number in table 7 are obtained at the reference wavelength 587nm, and the focal length is obtained at the reference wavelength 920 nm.

K in table 8 is a conic constant, and table 8 gives high-order coefficient values A4, A6, A8, a10, a12, a14, a16, a18, and a20 that can be used for each aspherical mirror surface in the fourth embodiment.

TABLE 7

TABLE 8

Referring to fig. 8, as can be seen from the longitudinal spherical aberration diagram (a) in fig. 8, the astigmatism diagram (B) in fig. 8, and the distortion diagram (C) in fig. 8, the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, as for the wavelengths corresponding to the curves in fig. 8 (a), fig. 8 (B), and fig. 8 (C), the contents described in the first embodiment with respect to fig. 2 (a), fig. 2 (B), and fig. 2 (C) may be referred to, and details thereof are not repeated herein.

Fifth embodiment

A schematic structural diagram of an optical lens 100 disclosed in the fifth embodiment of the present application is shown in fig. 9, where the optical lens 100 includes a stop STO, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an infrared band-pass filter 60, which are sequentially disposed from an object side to an image side along an optical axis O. For materials of the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4 and the fifth lens element L5, reference may be made to the above-mentioned specific embodiments, and details thereof are not repeated herein.

Further, the object-side surface 11 and the image-side surface 12 of the first lens element L1 are respectively convex and concave at the paraxial region O; the object-side surface 21 and the image-side surface 22 of the second lens element L2 are respectively convex and concave at the paraxial region O; the object-side surface 31 and the image-side surface 32 of the third lens element L3 are respectively convex and concave at the paraxial region O; the object-side surface 41 and the image-side surface 42 of the fourth lens element L4 are respectively convex and concave at the paraxial region O; the object-side surface 51 and the image-side surface 52 of the fifth lens element L5 are convex and concave, respectively, at the paraxial region O.

Specifically, the effective focal length f =3.65mm of the optical lens 100, the f-number FNO =1.28 of the optical lens 100, the field angle FOV =71.14deg of the optical lens 100, and the total length TTL =5.85mm of the optical lens 100 are taken as examples.

The other parameters in the fifth embodiment are given in table 9 below, and the definitions of the parameters can be obtained from the description of the previous embodiments, which are not repeated herein. It is understood that the units of the radius Y, the thickness, and the focal length in table 9 are all mm, and the refractive index and the abbe number in table 9 are obtained at the reference wavelength 587nm, and the focal length is obtained at the reference wavelength 920 nm.

K in table 10 is a conic constant, and table 10 gives high-order coefficient coefficients A4, A6, A8, a10, a12, a14, a16, a18, and a20 that can be used for each aspherical mirror surface in the fifth embodiment.

TABLE 9

Watch 10

Referring to fig. 10, as can be seen from the longitudinal spherical aberration diagram (a) in fig. 10, the astigmatism diagram (B) in fig. 10, and the distortion diagram (C) in fig. 10, the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, as for the wavelengths corresponding to the curves in fig. 10 (a), fig. 10 (B), and fig. 10 (C), the contents described in the first embodiment with respect to fig. 2 (a), fig. 2 (B), and fig. 2 (C) may be referred to, and details thereof are not repeated herein.

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

Relation/embodiment	First embodiment	Second embodiment	Third embodiment	Fourth embodiment	Fifth embodiment
						0.9<f/EPD<1.3	1.062	1.027	1.088	0.964	1.267
1.9<TTL/IMGH<2.2	2.009	2.096	2.197	1.986	2.167
						0.11<BFL/TTL<0.17	0.166	0.143	0.137	0.165	0.120
-0.5<f2/f1<0	-0.388	-0.315	-0.040	-0.492	-0.406
						-0.4<f2/f3<0	-0.327	-0.077	-0.293	-0.360	-0.292
0.8<CT2/CT3<1.9	1.002	0.856	1.821	1.271	1.026
						1.9<∑CT/∑AT<5	3.096	3.388	1.997	4.297	2.762
-5<f1/f34<0.5	-0.001	-1.217	-4.885	0.431	-0.650
						1<CT3/CT4<3	1.663	2.606	1.337	1.332	1.086
0.5<SD11/IMGH<0.6	0.533	0.571	0.572	0.533	0.533
						0<f/f5<1	0.549	0.159	0.450	0.946	0.018
SAG42/SAG51<3	-1517.555	2.685	1.234	-131.202	-1.748
						56deg<FOV/FNO<90deg	75.710deg	76.757deg	69.780deg	89.021deg	57.922deg

Referring to fig. 11, the present application further discloses a camera module 200, which includes an image sensor 201 and the optical lens 100 according to any of the first to fifth embodiments, wherein the image sensor 201 is disposed on an image side of the optical lens 100. The optical lens 100 is configured to receive an optical signal of a subject and project the optical signal to the image sensor 201, and the image sensor 201 is configured to convert the optical signal corresponding to the subject into an image signal, which is not described herein again. It can be understood that the camera module 200 having the optical lens 100 has the characteristics of large aperture and miniaturization while ensuring the imaging quality. 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 electronic device 300, wherein the electronic device 300 includes a housing 301 and the camera module 200, and the camera module 200 is disposed on the housing 301. The electronic device 300 may be, but not limited to, a mobile phone, a tablet computer, a notebook computer, a smart watch, a monitor, a car recorder, a car backing image, and the like. It can be understood that the electronic device 300 having the camera module 200 has all the technical effects of the optical lens. Namely, the imaging quality is ensured, and the imaging lens has the characteristics of large aperture and miniaturization. Since the above technical effects have been described in detail in the embodiments of the optical lens, they are not described herein again.

The optical lens, the camera module and the electronic device disclosed in the embodiments of the present invention are described in detail above, and the principle and the embodiments of the present invention are explained in detail herein by applying specific examples, and the description of the embodiments above is only used to help understanding the optical lens, the camera module and the electronic device and the core ideas 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 system includes five lens elements with refractive power, in order from an object side to an image side along an optical axis:

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

a third lens element with negative refractive power;

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

the optical lens satisfies the following relational expression:

0.9<f/EPD<1.3；

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

1.9 but less than TTL/IMGH <2.2; and/or, 0.11 is formed by the woven fabric with BFL/TTL less than 0.17;

wherein, TTL is a distance from an object side surface of the first lens element to an imaging surface of the optical lens along the optical axis, IMGH is a radius of a maximum effective imaging circle of the optical lens, and BFL is a minimum distance from an image side surface of the fifth lens element to the imaging surface of the optical lens along a direction parallel to the optical axis.

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

-0.5 yarn woven fabric of f2/f1<0, and-0.4 yarn woven fabric of f2/f3<0;

wherein f1 is a focal length of the first lens, f2 is a focal length of the second lens, and f3 is a focal length of the third lens.

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

wherein CT2 is the thickness of the second lens element on the optical axis, CT3 is the thickness of the third lens element on the optical axis, f2 is the focal length of the second lens element, and f3 is the focal length of the third lens element.

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

1.9< ∑ CT/Σ AT <5, and-0.4</f 2/f3<0;

Σ CT is the sum of the thicknesses of the first lens to the fifth lens on the optical axis, Σ AT is the sum of the air gaps of the first lens to the fifth lens on the optical axis, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

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

-5-t f1/f34<0.5, and 1-t ct3/CT4<3;

wherein f1 is a focal length of the first lens element, f34 is a combined focal length of the third lens element and the fourth lens element, CT3 is a thickness of the third lens element on the optical axis, and CT4 is a thickness of the fourth lens element on the optical axis.

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

0.5-woven SD11/IMGH <0.6, and 0<f/f5<1;

wherein SD11 is the maximum effective half aperture of the object-side surface of the first lens element, IMGH is the radius of the maximum effective imaging circle of the optical lens, and f5 is the focal length of the fifth lens element.

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

SAG42/SAG51<3, and 0<f/f5<1;

SAG42 is a distance from a position of the maximum effective aperture of the image-side surface of the fourth lens to an intersection point of the image-side surface of the fourth lens and the optical axis in a direction parallel to the optical axis, SAG51 is a distance from a position of the maximum effective aperture of the object-side surface of the fifth lens to an intersection point of the object-side surface of the fifth lens and the optical axis in the direction parallel to the optical axis, and f5 is a focal length of the fifth lens.

9. The utility model provides a module of making a video recording which characterized in that: the camera module comprises an optical lens according to any one of claims 1-8 and an image sensor, the image sensor being disposed on an image side of the optical lens.

10. An electronic device, characterized in that: the electronic device comprises a housing and the camera module of claim 9, the camera module being disposed on the housing.