CN113960759A

CN113960759A - Optical lens, camera module and electronic equipment

Info

Publication number: CN113960759A
Application number: CN202111307515.2A
Authority: CN
Inventors: 龙鑫灿; 李明; 刘秀; 曾晗
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2021-11-05
Filing date: 2021-11-05
Publication date: 2022-01-21
Anticipated expiration: 2041-11-05
Also published as: CN113960759B

Abstract

The invention discloses an optical lens, a camera module and electronic equipment, wherein the optical lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are arranged in sequence from an object side to an image side along an optical axis; the first lens element with negative refractive power has a convex object-side surface and a concave image-side surface, the second lens element with positive refractive power has a convex object-side surface, the sixth lens element with negative refractive power has a convex object-side surface and a concave image-side surface, and the optical lens assembly satisfies the following relationships: 3< (FNO × TTL)/IMGH <4, wherein FNO is the f-number of the optical lens, TTL is the distance between the object side surface of the first lens and the imaging surface of the optical lens on the optical axis, and IMGH is the radius of the maximum effective imaging circle on the imaging surface of the optical lens. The optical lens, the camera module and the electronic equipment provided by the invention can meet the requirements of light, thin and small design, improve the image quality of the optical lens, and improve the resolution and imaging definition of the optical lens so as to improve the shooting quality of the optical lens.

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

At present, with the development of the camera technology, people have higher and higher requirements on the imaging quality of the optical lens, and the optical lens is required to be lighter, thinner and smaller, and simultaneously has higher imaging quality. In order to achieve higher imaging quality, the optical lens needs to increase the number of lenses to correct aberrations. However, the increase in the number of lenses increases the difficulty of processing, molding and assembling the lenses, and increases the volume of the optical lens. Therefore, in the related art, under the design trend of light, thin and small optical lens, the image quality of the optical lens is poor, the resolution is low, and the imaging quality of the optical lens is not clear enough, so that it is difficult to meet the requirement of high-definition imaging of the optical lens.

Disclosure of Invention

The embodiment of the invention discloses an optical lens, a camera module and electronic equipment, which can improve the image quality of the optical lens and improve the resolution and imaging definition of the optical lens while realizing the light, thin and miniaturized design of the optical lens so as to improve the shooting quality of the optical lens and realize clear imaging.

In order to achieve the above object, in a first aspect, the present invention discloses an optical lens including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in order from an object side to an image side along an optical axis;

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 positive refractive power has a convex object-side surface at paraxial region;

the third lens element with refractive power;

the fourth lens element with refractive power;

the fifth lens element with refractive power;

the sixth 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 optical lens satisfies the following relation:

3<(FNO*TTL)/IMGH<4；

the FNO is the f-number of the optical lens, the TTL is the distance from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis, and the IMGH is the radius of the maximum effective imaging circle on the imaging surface of the optical lens.

In the optical lens provided by the application, due to the negative refractive power provided by the first lens, incident light rays are effectively diffused, so that the aperture of the optical lens is reduced while a larger view field range is maintained, and the small head characteristic of the optical lens is realized; meanwhile, the lens is matched with a meniscus shape which protrudes towards the object side at the position of a lower beam axis, so that the edge thickness of the first lens can be reduced, and the optical lens is light and thin; the second lens element with positive refractive power can well correct the huge aberration of the first lens element towards the negative direction; meanwhile, the design that the side surface of the object is convex at the position near the optical axis can further enhance the positive refractive power of the second lens element, which is beneficial to shortening the total optical length of the optical lens. The negative refractive power provided by the sixth lens element can balance the aberration which is difficult to correct and is caused by the lens elements (i.e. the first lens element to the fifth lens element) on the object side when converging the incident light; meanwhile, the design that the side face of the object is convex at the position close to the optical axis is beneficial to inhibiting the emergent angle of central field rays, spherical aberration and field curvature can be well inhibited, and the optical performance of the optical lens is improved so as to improve the imaging quality; and the design that the image side surface is concave at the position of a short optical axis is matched, so that the back focus of the optical lens is favorably ensured, and the assembly difficulty of the optical lens is reduced.

That is, by selecting a proper number of lenses and reasonably configuring the refractive power and the surface type of each lens, the light, thin and small design of the optical lens can be realized, the image quality of the optical lens can be improved, and the resolution and the imaging definition of the optical lens can be improved, so that the optical lens has a better imaging effect, and the high-definition imaging requirement of people on the optical lens can be met; and further causing the optical lens to satisfy the following relational expression: 3< (FNO × TTL)/IMGH <4, the f-number, the total optical length and the image height of the optical lens are reasonably configured, so that the optical lens can be designed to be light, thin and small, and has a larger image plane and a larger aperture, so that the optical lens can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens can be effectively improved, meanwhile, enough light transmission quantity can be provided, the dim light shooting condition is improved, the shot picture is more vivid, and the shooting requirement of high image quality and high definition is met. When the upper limit of the relation is exceeded, the aperture of the optical lens can be increased to provide enough light transmission quantity for the optical lens, but the optical total length of the optical lens is also increased, so that the design requirement of miniaturization is difficult to meet; when the light flux is lower than the lower limit of the relational expression, the aperture of the optical lens is small, so that the light flux of the optical lens is insufficient, the accuracy of the optical lens for capturing images is influenced, and the high-resolution imaging of the optical lens is not facilitated; meanwhile, the structure of the optical lens is too compact, so that the aberration correction difficulty is increased, and the imaging performance of the optical lens is easily reduced.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 3.6mm < EFL/tan (HFOV) <6.3 mm; wherein EFL is an effective focal length of the optical lens, and HFOV is half of a maximum field angle of the optical lens.

When the limitation of the conditional expression is satisfied, the effective focal length and the maximum field angle of the optical lens can be reasonably configured, the aberration of the optical lens can be favorably corrected under the condition that the total optical length of the optical lens is shortened, and the optical lens which is small in size and good in imaging quality is obtained; meanwhile, the optical lens has the characteristic of large visual angle, so that more scene contents can be acquired, and imaging information of the optical lens is enriched. When the angle of view of the optical lens is lower than the lower limit of the relational expression, the distortion of the external field of view is too large, the distortion phenomenon of the periphery of an image can be caused, and the imaging performance of the optical lens is reduced; when the optical length exceeds the upper limit of the above relational expression, the focal length of the optical lens is too long, so that the optical total length of the optical lens is difficult to compress, the volume of the optical lens is increased, and the optical lens is not favorable for meeting the miniaturization design requirement.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 1.5< R11/R12< 3; wherein R11 is a radius of curvature of an object-side surface of the sixth lens element at an optical axis, and R12 is a radius of curvature of an image-side surface of the sixth lens element at the optical axis.

When the limitation of the relational expression is met, the trend of the thickness ratio of the object side surface and the image side surface of the sixth lens can be well controlled, so that the shape of the sixth lens is limited, the spherical aberration contribution of the sixth lens can be controlled within a reasonable range, the image quality of an on-axis visual field and an off-axis visual field can not be obviously degraded due to the contribution of spherical aberration, the spherical aberration of the optical lens can be effectively improved, and the optical performance of the optical lens is improved; meanwhile, the processability of the shape of the sixth lens is ensured, so that the processing production of the sixth lens is ensured, and the manufacturing yield of the sixth lens is improved. When the range of the relational expression is exceeded, the surface of the sixth lens is excessively bent or flat, which is not beneficial to the processing and forming of the sixth lens, so that the manufacturing yield of the sixth lens cannot be ensured; meanwhile, the correction of the edge aberration of the optical lens is not facilitated, and the probability of generating the ghost or the intensity of the ghost is possibly increased, so that the imaging quality 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< (CT1+ CT2+ CT3+ CT4)/CT1< 7.5; wherein CT1 is an axial thickness of the first lens element, CT2 is an axial thickness of the second lens element, CT3 is an axial thickness of the third lens element, and CT4 is an axial thickness of the fourth lens element.

When the limitation of the relational expression is met, the thicknesses of the front four lenses of the optical lens are controlled within a proper range, so that the thicknesses of the front four lenses of the optical lens can be reasonably configured, the overall structure of the optical lens is more compact, the optical total length of the optical lens is regulated and controlled, the optical total length of the optical lens is shortened, and the design requirements of miniaturization and lightness and thinness of the optical lens are met. When the range of the relation is exceeded, the thickness compression of the front four lenses of the optical lens is insufficient, which is not beneficial to the miniaturization design of the optical lens; or the thickness of the front four lenses of the optical lens is too thin, and the bearing force among the lenses is insufficient when the lenses are assembled and arranged, so that the assembly and the forming of the lenses are difficult, and the optical lens is poor in assembly stability and poor in manufacturability.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 2< | f1/EFL | < 3.5; wherein f1 is the focal length of the first lens, and EFL is the effective focal length of the optical lens.

When the limitation of the relational expression is met, the optical lens is ensured to have a larger field range, and the object space imaging range of the optical lens can be enlarged, so that all optical information from the object space to the image space, which is provided for each lens by the first lens, can be shot, the optical lens can acquire more scene contents, and the imaging information of the optical lens is enriched. When the absolute value of the focal length of the first lens element exceeds the upper limit of the above relation, the refractive power of the first lens element is too weak, which is not favorable for the first lens element to collect the light from the object side and is not favorable for the light with large angle to enter the optical lens, thereby reducing the light transmission amount, reducing the field range of the optical lens and being difficult to meet the shooting requirement. When the absolute value of the focal length of the first lens element is smaller than the lower limit of the above relation, the refractive power is too strong, which not only increases the sensitivity of the optical lens and makes the processing difficult, but also makes it difficult to correct the aberration generated by the first lens element, thereby 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: 1.7< AAG/Gmax < 2.8; wherein AAG is a sum of air gaps on an optical axis between two adjacent lenses of the first to sixth lenses, Gmax is a maximum air gap among the air gaps on the optical axis between two adjacent lenses of the first to sixth lenses, and the air gap on the optical axis between two adjacent lenses is: the distance from the image-side surface of the front lens to the object-side surface of the rear lens on the optical axis, for example, the distance from the image-side surface of the first lens to the object-side surface of the second lens on the optical axis.

The proportional relation between the maximum air gap of the five air gaps and the sum of the five air gaps is reasonably defined, the air gap between two adjacent lenses is controlled within a proper range, and the optical lens is favorable to have enough air gap ratio, so that the stability and the imaging quality of the optical lens are ensured; meanwhile, the optical total length of the optical lens can be further regulated, the optical total length of the optical lens can be shortened, the optical lens is miniaturized, the assembling difficulty of each lens is reduced, and the assembling stability of each lens is improved; in addition, the overall structure compactness of the optical lens is improved, so that the internal space of the optical lens can be fully utilized, the risks of stray light and ghost images between adjacent lenses can be reduced, the imaging light can be gathered, the aberration can be improved, the distortion can be reduced, and the whole optical lens can effectively expand the field angle and maintain good imaging quality. When the range of the relation is exceeded, the space gap between two adjacent lenses is large, so that the total optical length of the optical lens is not sufficiently compressed, the miniaturization design of the optical lens is not facilitated, and meanwhile, the assembly molding of the lenses is difficult, so that the assembly stability of the optical lens is poor, and the manufacturability is poor.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 0.4< f2/f123< 2.5; wherein f2 is the focal length of the second lens, and f123 is the combined focal length of the first lens, the second lens and the third lens.

When the limitation of the relational expression is met, the specific relation between the focal length of the second lens and the combined focal length of the first lens, the second lens and the third lens can be reasonably configured, the surface type design from the first lens to the third lens can be matched to reasonably guide light rays with large-angle incidence to smoothly enter the optical lens, the effective correction of the spherical aberration and the axial chromatic aberration of the optical lens can be facilitated, the light ray deflection can be slowed down, the light ray deflection angle can be reduced, the resolving capability of the optical lens can be improved, and the imaging quality of the optical lens can be improved. When the focal length of the second lens element is beyond the range of the above relationship, the difference between the focal length of the second lens element and the focal length of the combination of the first lens element, the second lens element and the third lens element is large, which easily causes the light beam to be deflected too much, so that the optical lens is prone to generate a severe astigmatism phenomenon, resulting in the reduction of the imaging quality of the optical lens.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 0.2< SD11/IMGH < 0.4; wherein SD11 is the maximum effective half aperture of the object side surface of the first lens.

When the limitation of the relational expression is met, the aperture of the object side surface of the first lens and the image height of the optical lens are reasonably configured, and the radial size of the first lens is reduced, so that the optical lens with the six-piece type structure realizes small-head design, the size of an opening on a screen of equipment can be reduced, and the screen occupation ratio of the equipment is improved. In addition, when the limitation of the relational expression is met, the processing and forming of the first lens are facilitated, the optical lens is provided with a large aperture, the optical lens not only has a smaller depth of field so as to enable the shot picture to be more vivid, but also has a proper light inlet amount, so that the dim light shooting condition can be improved, the shot picture is more vivid, and the high-image-quality and high-definition shooting effect is realized; meanwhile, the optical lens can acquire more scene contents, imaging information of the optical lens is enriched, and shooting experience of a user is improved. When the maximum effective aperture of the first lens exceeds the upper limit of the relational expression, the maximum effective aperture of the first lens is too large, and the small head design is difficult to realize; when the image height of the optical lens is lower than the lower limit of the relational expression, the image height of the optical lens is overlarge relative to the maximum effective aperture of the object side surface of the first lens, so that the deflection degree of incident light in the optical lens is overlarge, the off-axis aberration is easily increased, and the imaging quality is not favorably improved.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relation: 0.4< | (SAG1-SAG2)/SAG1| < 0.9; the lens comprises a first lens, a second lens and a third lens, wherein SAG1 is the distance on an optical axis from the intersection point of an object side surface of the first lens and an optical axis to the maximum effective radius of the object side surface of the first lens, SAG1 is the saggital height from the maximum effective radius of the object side surface of the first lens, SAG2 is the distance on the optical axis from the intersection point of an image side surface of the first lens and the optical axis to the maximum effective radius of the image side surface of the first lens, and SAG2 is the saggital height from the maximum effective radius of the image side surface of the first lens.

When the limitation of the relational expression is met, a reasonable surface shape can be obtained by controlling the ratio of rise at the maximum effective radius position of the object side surface and the image side surface of the first lens to be in a reasonable range, and the surface shapes of the object side surface and the image side surface of the first lens are close to each other, so that peripheral light rays can be smoothly transited on one hand, the light rays can be conveniently controlled to enter the optical lens at a small deflection angle, the field curvature and the distortion of the optical lens are reduced, and the resolving power of the optical lens is improved; on the other hand, the sensitivity of the first lens is favorably reduced, the processing difficulty of the first lens is reduced, and the first lens is convenient to machine and form. When the range of the relation is exceeded, the surface of the first lens is too curved or too flat, so that the processing difficulty of the first lens is increased, and the production cost of the first lens is increased; meanwhile, edge aberration is easy to generate, and the image quality of the optical lens is not improved.

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. The camera module with the optical lens can meet the requirements of light, thin and small design, and simultaneously can improve the image quality of the optical lens, improve the resolution and imaging definition of the optical lens, improve the shooting quality of the optical lens and realize clear imaging; meanwhile, the optical lens has a larger image plane and a larger aperture, so that the optical lens can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens can be effectively improved, meanwhile, enough light flux can be provided, the dim light shooting condition is improved, the shot picture is more vivid, and the shooting requirement of high image quality and high definition is met.

In a third aspect, the invention further discloses an electronic device, which includes a housing and the camera module set according to the second aspect, and the camera module set is disposed on the housing. The electronic equipment with the camera module can meet the requirements of light, thin and small design, and simultaneously can improve the image quality of the optical lens, improve the resolution and imaging definition of the optical lens, so as to improve the shooting quality of the optical lens and realize clear imaging; meanwhile, the optical lens has a larger image plane and a larger aperture, so that the optical lens can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens can be effectively improved, meanwhile, enough light flux can be provided, the dim light shooting condition is improved, the shot picture is more vivid, and the shooting requirement of high image quality and high definition is met.

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

according to the optical lens, the camera module and the electronic equipment provided by the embodiment of the invention, the optical lens adopts six lens, the number of the lenses is reasonable, the structure is ingenious, and the volume is smaller. By selecting a proper number of lenses and reasonably configuring the refractive power and the surface type of each lens, the light, thin and small design of the optical lens can be realized, the image quality of the optical lens can be improved, and the resolution and the imaging definition of the optical lens can be improved, so that the optical lens has a better imaging effect, and the high-definition imaging requirement of people on the optical lens can be met; and further causing the optical lens to satisfy the following relational expression: 3< (FNO × TTL)/IMGH <4 >, the optical lens's f-number, optics total length and image height obtain reasonable configuration, can satisfy optical lens's frivolous, miniaturized design simultaneously, make optical lens has great image plane and great light ring, so that optical lens can match the sensitization chip of higher pixel better, can improve optical lens's image quality effectively, can also provide sufficient light flux simultaneously, improve the dim light shooting condition, make the picture of shooing more vivid, satisfy the shooting demand of high picture quality high definition.

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 light ray 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 light ray 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 light ray 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 light ray 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 light ray 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.

Furthermore, the terms "first," "second," and the like, are used primarily to distinguish one device, element, or component from another (the specific nature and configuration may be the same or different), 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, where the optical lens 100 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6, 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 and the sixth lens L6 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, the fourth lens element L4 and the fifth lens element L5 all have refractive power (e.g., positive refractive power or negative refractive power), and the sixth lens element L6 has negative refractive power.

Further, the object-side surface S1 of the first lens element L1 can be convex at the paraxial region O, and the image-side surface S2 of the first lens element L1 can be concave at the paraxial region O; the object-side surface S3 of the second lens element L2 can be convex at the paraxial region O, and the image-side surface S4 of the second lens element L2 can be concave or convex at the paraxial region O; the object-side surface S5 of the third lens element L3 can be convex or concave at the paraxial region O, and the image-side surface S6 of the third lens element L3 can be convex or concave at the paraxial region O; the object-side surface S7 of the fourth lens element L4 can be convex or concave at the paraxial region O, and the image-side surface S8 of the fourth lens element L4 can be convex or concave at the paraxial region O; the object-side surface S9 of the fifth lens element L5 can be concave or concave at the paraxial region O, and the image-side surface S10 of the fifth lens element L5 can be convex or convex at the paraxial region O; the object-side surface S11 of the sixth lens element L6 may be convex at the paraxial region O, and the image-side surface S12 of the sixth lens element L6 may be concave at the paraxial region O.

In the optical lens 100 provided by the present application, due to the negative refractive power provided by the first lens element L1, the incident light is effectively diffused, which is beneficial to maintaining a larger field range, and at the same time, reducing the aperture of the optical lens 100, thereby realizing the small head characteristic of the optical lens 100; meanwhile, the lens is matched with a meniscus shape which protrudes towards the object side at the position near the optical axis O, so that the edge thickness of the first lens L1 can be reduced, and the optical lens 100 is light and thin; the second lens element L2 with positive refractive power can correct the large negative aberration of the first lens element L1; meanwhile, the design that the object side surface is convex at the paraxial region O can further enhance the positive refractive power of the second lens element L2, which is favorable for shortening the total optical length of the optical lens system 100. The negative refractive power provided by the sixth lens element L6 can balance the aberration of each of the object-side lens elements (i.e., the first lens element L1 through the fifth lens element L5) that is difficult to correct when converging the incident light; meanwhile, the design that the side surface of the object is convex at the position close to the optical axis O is beneficial to inhibiting the emergent angle of central field rays, spherical aberration and field curvature can be well inhibited, and the optical performance of the optical lens 100 is improved so as to improve the imaging quality; and the design that the image side surface is concave at the position near the optical axis O is favorable for ensuring the back focus of the optical lens 100 and reducing the assembly difficulty of the optical lens 100.

Considering that the optical lens 100 is mostly applied to electronic devices such as mobile phones, tablet computers, smartwatches, etc., the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 may all be made of plastic, so that the optical lens 100 has a good optical effect, and at the same time, the overall weight of the optical lens 100 may be reduced, and the optical lens 100 may have good portability, and may be easier to process lens with complex surface. Meanwhile, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 may all 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 object side of the optical lens 100 and the object side S1 of the first lens L1. It is understood that, in other embodiments, the stop 102 may also be disposed between two adjacent lenses, for example, between the second lens L2 and the third lens L3, 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 optical filter L7, for example, an infrared filter, which may be disposed between the image side surface S12 of the sixth lens element L6 and the image plane 101 of the optical lens 100, so as to filter out light rays in other bands, such as visible light, and only allow infrared light to pass through, so that the infrared filter is selected to filter out infrared light, thereby improving the imaging quality and making the imaging better conform to the visual experience of human eyes; and the optical lens 100 can be used as an infrared optical lens, that is, the optical lens 100 can image in a dark environment and other special application scenes and can obtain a better image effect. It is understood that the optical filter L7 may be made of an optical glass coating film, a colored glass, or 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< (FNO) TTL)/IMGH < 4; wherein FNO is an f-number of the optical lens 100, TTL is a distance from the object-side surface S1 of the first lens element L1 to the imaging surface 101 of the optical lens 100 on the optical axis O, and IMGH is a radius of a maximum effective imaging circle on the imaging surface 101 of the optical lens 100.

When the limitation of the above conditional expressions is satisfied, the f-number, the total optical length and the image height of the optical lens 100 are reasonably configured, and the light, thin and miniaturized design of the optical lens 100 can be satisfied, and meanwhile, the optical lens 100 has a larger image plane and a larger aperture, so that the optical lens 100 can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens 100 can be effectively improved, meanwhile, a sufficient light transmission amount can be provided, the dim light shooting condition is improved, a shot picture is more vivid, and the shooting requirement of high image quality and high definition is satisfied. When the upper limit of the above relation is exceeded, the aperture of the optical lens 100 can be increased to provide a sufficient amount of light to the optical lens 100, but the total optical length of the optical lens 100 is also increased, which makes it difficult to meet the design requirement of miniaturization; when the lower limit of the above relation is lower, the aperture of the optical lens 100 is small, which results in insufficient light transmission of the optical lens 100, and thus the accuracy of capturing images by the optical lens 100 is affected, which is not favorable for high-resolution imaging of the optical lens 100; meanwhile, the structure of the optical lens 100 is too compact, so that the difficulty of aberration correction is increased, and the imaging performance of the optical lens 100 is easily reduced.

In some embodiments, the optical lens 100 satisfies the following relationship: 3.6mm < EFL/tan (HFOV) <6.3 mm; where EFL is the effective focal length of the optical lens 100, and HFOV is half of the maximum field angle of the optical lens 100.

When the restrictions of the above conditional expressions are satisfied, the effective focal length and the maximum angle of view of the optical lens 100 can be reasonably arranged, and it is possible to ensure that the aberration of the optical lens 100 can be favorably corrected even when the total optical length of the optical lens 100 is shortened, which contributes to obtaining an optical lens that is both compact and has good imaging quality; meanwhile, the optical lens 100 has a large viewing angle characteristic, so that more scene contents can be acquired, and imaging information of the optical lens 100 is enriched. When the angle of view is lower than the lower limit of the above relational expression, the field angle of view of the optical lens 100 is too large, which causes too large distortion of the external field of view, resulting in distortion of the periphery of the image and reduced imaging performance of the optical lens 100; if the upper limit of the above relation is exceeded, the focal length of the optical lens 100 is too long to compress the total optical length of the optical lens 100, which increases the volume of the optical lens 100, and is not favorable for the optical lens 100 to meet the design requirement of miniaturization.

In some embodiments, the optical lens 100 satisfies the following relationship: 1.5< R11/R12< 3; wherein R11 is a curvature radius of the object-side surface S11 of the sixth lens element L6 on the optical axis O, and R12 is a curvature radius of the image-side surface S12 of the sixth lens element L6 on the optical axis O.

When the limitation of the above relation is satisfied, the aspect ratio of the object-side surface S11 and the image-side surface S12 of the sixth lens element L6 can be well controlled, so as to limit the shape of the sixth lens element L6, and thus, the amount of spherical aberration contribution of the sixth lens element L6 can be controlled within a reasonable range, so that the image quality of the on-axis field of view and the off-axis field of view is not significantly degraded due to the spherical aberration contribution, and thus the spherical aberration of the optical lens element 100 can be effectively improved, and the optical performance of the optical lens element 100 can be improved; meanwhile, the workability of the shape of the sixth lens L6 is ensured, the processing production of the sixth lens L6 is ensured, and the manufacturing yield of the sixth lens L6 is improved. When the range of the above relational expression is exceeded, the surface of the sixth lens L6 is excessively curved or flat, which is disadvantageous to the processing and molding of the sixth lens L6, and thus the manufacturing yield of the sixth lens L6 cannot be ensured; meanwhile, it is not beneficial to correct the edge aberration of the optical lens 100, and it may increase the probability of generating the ghost or increase the intensity of the ghost, which affects the imaging quality.

In some embodiments, the optical lens 100 satisfies the following relationship: 4< (CT1+ CT2+ CT3+ CT4)/CT1< 7.5; wherein CT1 is the thickness of the first lens element L1 on the optical axis O, CT2 is the thickness of the second lens element L2 on the optical axis O, CT3 is the thickness of the third lens element L3 on the optical axis O, and CT4 is the thickness of the fourth lens element L4 on the optical axis O.

When the limitation of the above relation is satisfied, the thicknesses of the front four lenses of the optical lens 100 are controlled within a proper range, so that the thicknesses of the front four lenses of the optical lens 100 can be reasonably configured, which is beneficial to making the overall structure of the optical lens 100 more compact, regulating and controlling the optical overall length of the optical lens 100, and shortening the optical overall length of the optical lens 100, so as to satisfy the design requirements of miniaturization and lightness of the optical lens 100. When the range of the above relation is exceeded, the thickness of the front four lenses of the optical lens 100 is not sufficiently compressed, which is not favorable for the miniaturization design of the optical lens 100; or the thickness of the front four lenses of the optical lens 100 may be too thin, and the bearing force between the lenses is insufficient when assembling and arranging, which makes the lens assembly difficult, so that the assembly stability of the optical lens 100 is poor and the manufacturability is poor.

In some embodiments, the optical lens 100 satisfies the following relationship: 2< | f1/EFL | < 3.5; where f1 is the focal length of the first lens L1, and EFL is the effective focal length of the optical lens 100.

When the limitation of the above relation is satisfied, the optical lens 100 is ensured to have a larger field range, and the object space imaging range of the optical lens 100 can be increased, so that all optical information from the object space to the image space provided by the first lens L1 for each lens can be shot, and the optical lens 100 can acquire more scene contents and enrich the imaging information of the optical lens 100. When the absolute value of the focal length of the first lens element L1 is too large, the refractive power is too weak, which is not favorable for the first lens element L1 to collect the light from the object side, and is unfavorable for the light with large angle to enter the optical lens 100, so that the amount of transmitted light is reduced, the field range of the optical lens 100 is reduced, and the shooting requirement is difficult to satisfy. When the absolute value of the focal length of the first lens element L1 is too small, the refractive power is too strong, which not only increases the sensitivity of the optical lens assembly 100 and makes the processing difficult, but also makes it difficult to correct the aberration generated by the first lens element L1, and reduces the imaging quality.

In some embodiments, the optical lens 100 satisfies the following relationship: 1.7< AAG/Gmax < 2.8; wherein AAG is a sum of air gaps on the optical axis O between two adjacent lenses of the first lens L1 to the sixth lens L6, Gmax is a maximum air gap in the air gaps on the optical axis O between two adjacent lenses of the first lens L1 to the sixth lens L6, and the air gap on the optical axis between two adjacent lenses is: the distance on the optical axis from the image-side surface of the front lens to the object-side surface of the rear lens, for example, the distance on the optical axis O from the image-side surface S2 of the first lens L1 to the object-side surface S3 of the second lens L2.

The proportional relation between the maximum air gap of the five air gaps and the sum of the five air gaps is reasonably defined, the air gap between two adjacent lenses is controlled within a proper range, and the optical lens 100 is favorable to have enough air gap ratio, so that the stability and the imaging quality of the optical lens 100 are ensured; meanwhile, the optical total length of the optical lens 100 can be further regulated, the optical total length of the optical lens 100 can be shortened, the miniaturization design of the optical lens 100 can be realized, the assembly difficulty of each lens can be reduced, and the assembly stability of each lens can be improved; moreover, the overall structure compactness of the optical lens 100 is improved, so that the optical lens 100 can fully utilize the internal space thereof, thereby reducing the risks of stray light and ghost images between adjacent lenses, helping the collection of imaging light, improving aberration and reducing distortion, and effectively enabling the whole optical lens 100 to expand the angle of view and maintain good imaging quality. When the range of the above relation is exceeded, the spatial gap between two adjacent lenses is large, which may result in insufficient compression of the total optical length of the optical lens 100, which is not favorable for the miniaturization design of the optical lens 100, and may also result in difficulty in assembling and molding the lenses, so that the optical lens 100 has poor assembling stability and poor manufacturability.

In some embodiments, the optical lens 100 satisfies the following relationship: 0.4< f2/f123< 2.5; wherein f2 is the focal length of the second lens L2, and f123 is the combined focal length of the first lens L1, the second lens L2 and the third lens L3.

When the limitation of the above relation is satisfied, the ratio relationship between the focal length of the second lens L2 and the combined focal length of the first lens L1, the second lens L2, and the third lens L3 can be configured reasonably, and the light rays incident at a large angle can be guided reasonably and smoothly enter the optical lens 100 by matching with the surface shape design of the first lens L1 to the third lens L3, so that the spherical aberration and the axial chromatic aberration of the optical lens 100 can be corrected effectively, the light ray deflection can be slowed down, the light ray deflection angle can be reduced, the resolving power of the optical lens 100 can be improved, and the imaging quality of the optical lens 100 can be improved. When the focal length of the second lens element L2 is larger than the combined focal length of the first lens element L1, the second lens element L2 and the third lens element L3, the light beam is easily deflected too much, so that the optical lens system 100 is prone to generate a serious astigmatism, and the imaging quality of the optical lens system 100 is reduced.

In some embodiments, the optical lens 100 satisfies the following relationship: 0.2< SD11/IMGH < 0.4; SD11 is the maximum effective half aperture of the object-side surface S1 of the first lens L1.

When the limitation of the above relational expression is satisfied, the aperture of the object-side surface S1 of the first lens L1 and the image height of the optical lens 100 are reasonably arranged, and the radial dimension of the first lens L1 is reduced, so that the optical lens 100 having the six-piece structure is designed to have a small head, thereby reducing the size of the opening on the screen of the device and further improving the screen occupation ratio of the device. In addition, when the limitation of the above relational expression is satisfied, the processing and molding of the first lens L1 are facilitated, and the optical lens 100 has a larger aperture, so that the optical lens 100 not only has a smaller depth of field to make the shot picture more vivid, but also can make the optical lens 100 have a proper light entering amount, thus not only improving the dim light shooting condition, making the shot picture more vivid and realizing a high-image-quality and high-definition shooting effect; meanwhile, the optical lens 100 can acquire more scene contents, imaging information of the optical lens 100 is enriched, and shooting experience of a user is improved. If the upper limit of the above relational expression is exceeded, the maximum effective aperture of the first lens L1 becomes too large, and it becomes difficult to realize a small head design; when the image height of the optical lens 100 is lower than the lower limit of the above relation, the maximum effective aperture of the object-side surface S1 of the first lens element L1 is too large, which causes the degree of deflection of the incident light in the optical lens 100 to be too large, thereby increasing the off-axis aberration easily, which is not favorable for improving the imaging quality.

In some embodiments, the optical lens 100 satisfies the following relationship: 0.4< | (SAG1-SAG2)/SAG1| < 0.9; the SAG1 is a distance on the optical axis from an intersection point of the object-side surface S1 of the first lens L1 and the optical axis O to the maximum effective radius of the object-side surface S1 of the first lens L1, the SAG1 is a rise at the maximum effective radius of the object-side surface S1 of the first lens L1, the SAG2 is a distance on the optical axis O from an intersection point of the image-side surface S2 of the first lens L1 and the optical axis O to the maximum effective radius of the image-side surface S2 of the first lens L1, and the SAG2 is a rise at the maximum effective radius of the image-side surface S2 of the first lens L1.

When the definition of the above relation is satisfied, by controlling the ratio of the rise at the maximum effective radius of the object-side surface S1 and the image-side surface S2 of the first lens L1 within a reasonable range, a reasonable surface shape can be obtained, and the surface shapes of the object-side surface S1 and the image-side surface S2 of the first lens L1 can be made to be similar, so that, on one hand, peripheral light rays can be smoothly transited, so that the light rays can be controlled to enter the optical lens 100 at a smaller deflection angle, curvature of field and distortion of the optical lens 100 are reduced, and the resolving power of the optical lens 100 is improved; on the other hand, the sensitivity of the first lens L1 is reduced, the processing difficulty of the first lens L1 is reduced, and the processing and forming of the first lens L1 are facilitated. When the range of the above relation is exceeded, the surface of the first lens L1 is too curved or too flat, resulting in an increased difficulty in processing the first lens L1, increasing the production cost of the first lens L1; meanwhile, edge aberration is easily generated, which is not favorable for improving the image quality 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

In a configuration diagram of an optical lens 100 disclosed in the first embodiment of the present application, as shown in fig. 1, the optical lens 100 includes a stop 102, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter L7, which are sequentially disposed 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 positive refractive power, the third lens element L3 with positive refractive power, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative 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 and the sixth lens L6, reference may be made to the above-mentioned specific embodiments, and further description is omitted here.

Further, the object-side surface S1 and the image-side surface S2 of the first lens element L1 are convex and concave, respectively, at the paraxial region O; the object-side surface S3 and the image-side surface S4 of the second lens element L2 are convex and concave, respectively, at a paraxial region O; the object-side surface S5 and the image-side surface S6 of the third lens element L3 are convex at the paraxial region O; the object-side surface S7 and the image-side surface S8 of the fourth lens element L4 are both concave at the paraxial region O; the object-side surface S9 and the image-side surface S10 of the fifth lens element L5 are concave and convex, respectively, at a paraxial region O; the object-side surface S11 and the image-side surface S12 of the sixth lens element L6 are convex and concave, respectively, at a paraxial region O.

Specifically, other parameters of the optical lens 100 are given in table 1 below, taking as an example that the effective focal length EFL of the optical lens 100 is 4.3253mm, half of the maximum field angle HFOV of the optical lens 100 is 34.8958 °, the total optical length TTL of the optical lens 100 is 5.32mm, and the f-number FNO is 1.248. 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 radius Y in table 1 is the radius of curvature 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 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 to the image side of the last lens of the first lens L1 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. And the reference wavelengths of the effective focal length, refractive index and abbe number of each lens in table 1 are 587.56 nm.

TABLE 1

In the first embodiment, the object-side surface and the image-side surface of any one of the first lens L1 through the sixth lens L6 are aspheric, and the surface shape 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 being 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 that can be used for the respective aspherical mirror surfaces S1-S14 in the first embodiment.

TABLE 2

Referring to fig. 2 (a), fig. 2 (a) shows a light spherical aberration curve of the optical lens 100 in the first embodiment at 486.13nm, 587.56nm and 656.27 nm. In fig. 2 (a), the abscissa in the X-axis direction represents the focus shift, 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 diagram of astigmatism of light of the optical lens 100 in the first embodiment at a wavelength of 587.56 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. The astigmatism curves represent the meridional image plane curvature T and the sagittal image plane curvature S, 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 587.56 nnm.

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 587.56 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 the wavelength 587.56 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 stop 102, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter L7, which are disposed in this order from the object side to the image side along the optical axis O. The first lens element L1 with negative refractive power, the second lens element L2 with positive refractive power, the third lens element L3 with positive refractive power, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative 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 and the sixth lens L6, reference may be made to the above-mentioned specific embodiments, and further description is omitted here.

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 object-side surface S5 and the image-side surface S6 of the third lens element L3 are respectively convex and concave at the paraxial region O, and the object-side surface S7 and the image-side surface S8 of the fourth lens element L4 are respectively convex and concave at the paraxial region O; the object-side surface S9 and the image-side surface S10 of the fifth lens element L5 are convex at the paraxial region O.

In the second embodiment, the effective focal length EFL of the optical lens 100 is 4.2739mm, half of the maximum field angle HFOV of the optical lens 100 is 36.3249 °, the total optical length TTL of the optical lens 100 is 5.24mm, and the f-number FNO is 2.2.

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 all mm. And the reference wavelength of the effective focal length, refractive index, abbe number of each lens in table 3 is 587.56 nm.

TABLE 3

In the second embodiment, table 4 gives the high-order term coefficients that can be used for each aspherical mirror surface 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 (a) in fig. 4, 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 the wavelength 587.56 nm. As can be seen from (C) in fig. 4, the distortion of the optical lens 100 is well corrected at the wavelength 587.56 nm.

Third embodiment

Referring to fig. 5, fig. 5 is a schematic structural diagram of an optical lens 100 according to a third embodiment of the present application. The optical lens 100 includes a stop 102, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter L7, which are disposed in this order from the object side to the image side along the optical axis O. 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 negative refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative 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 and the sixth lens L6, reference may be made to the above-mentioned specific embodiments, and further description is omitted 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 object-side surface S3 and the image-side surface S4 of the second lens element L2 are convex at the paraxial region O, the object-side surface S5 and the image-side surface S6 of the third lens element L3 are concave at the paraxial region O, and the object-side surface S7 and the image-side surface S8 of the fourth lens element L4 are convex and concave at the paraxial region O, respectively; the object-side surface S9 and the image-side surface S10 of the fifth lens element L5 are convex and concave, respectively, at a paraxial region O.

In the third embodiment, an effective focal length EFL of the optical lens 100 is 3.7525mm, a half of a maximum field angle HFOV of the optical lens 100 is 39.0807 °, a total optical length TTL of the optical lens 100 is 4.620mm, and an f-number FNO of 2.3 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. And the reference wavelength of the effective focal length, refractive index, abbe number of each lens in table 5 is 587.56 nm.

TABLE 5

In the third embodiment, table 6 gives the high-order term coefficients that can be used for each aspherical mirror surface 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 the optical lens 100 according to the third embodiment, and specific definitions are described with reference to the first embodiment and will not be repeated herein. As can be seen from (a) in fig. 6, the spherical aberration value of the optical lens 100 in the third embodiment is better, which illustrates 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 the wavelength 587.56 nm. As can be seen from (C) in fig. 6, the distortion of the optical lens 100 is well corrected at the wavelength 587.56 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 stop 102, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter L7, which are disposed in this order from the object side to the image side along the optical axis O. 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, the fifth lens element L5 with negative refractive power and the sixth lens element L6 with negative 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 and the sixth lens L6, reference may be made to the above-mentioned specific embodiments, and further description is omitted here.

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 S3 and the image-side surface S4 of the second lens element L2 are convex at the paraxial region O, the object-side surface S5 and the image-side surface S6 of the third lens element L3 are concave at the paraxial region O, and the object-side surface S7 and the image-side surface S8 of the fourth lens element L4 are convex at the paraxial region O; the object-side surface S9 and the image-side surface S10 of the fifth lens element L5 are concave at the paraxial region O.

In the fourth embodiment, the focal length EFL of the optical lens 100 is 3.8646mm, half of the maximum field angle HFOV of the optical lens 100 is 38.3796 °, the total optical length TTL of the optical lens 100 is 5.043mm, and the f-number FNO is 2.30.

Other parameters in the fourth embodiment are shown 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. And the reference wavelength of the effective focal length, refractive index, abbe number of each lens in table 7 is 587.56 nm.

TABLE 7

In the fourth embodiment, table 8 gives the high-order term coefficients that can be used for each aspherical mirror surface 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 (a) in fig. 8, the spherical aberration value of the optical lens 100 in the fourth embodiment is better, which illustrates 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 the wavelength 587.56 nm. As can be seen from (C) in fig. 8, the distortion of the optical lens 100 is well corrected at the wavelength 587.56 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 stop 102, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter L7, which are disposed in this order from the object side to the image side along the optical axis O. 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 negative refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative 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 and the sixth lens L6, reference may be made to the above-mentioned specific embodiments, and further description is omitted 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 object-side surface S3 and the image-side surface S4 of the second lens element L2 are convex at the paraxial region O, the object-side surface S5 and the image-side surface S6 of the third lens element L3 are concave at the paraxial region O, and the object-side surface S7 and the image-side surface S8 of the fourth lens element L4 are concave and convex at the paraxial region O, respectively; the object-side surface S9 and the image-side surface S10 of the fifth lens element L5 are convex and concave, respectively, at a paraxial region O.

In the fifth embodiment, the focal length EFL of the optical lens 100 is 3.3315mm, half of the maximum field angle HFOV of the optical lens 100 is 42.5756 °, the total optical length TTL of the optical lens 100 is 4.35mm, and the f-number FNO is 2.30.

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. And the reference wavelength of the effective focal length, refractive index, abbe number of each lens in table 9 is 587.56 nm.

TABLE 9

In the fifth embodiment, table 10 gives the high-order term coefficients that can be used for each aspherical mirror surface in the fifth embodiment, wherein each aspherical mirror surface type can be defined by the formula given in the first embodiment.

Watch 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 (a) in fig. 10, the spherical aberration value of the optical lens 100 in the fifth embodiment is better, which illustrates 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 the wavelength 587.56 nm. As can be seen from (C) in fig. 10, the distortion of the optical lens 100 is well corrected at the wavelength 587.56 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 electronic device having the camera module 200 can satisfy the light, thin and miniaturized design, and at the same time, not only can improve the painting quality of the optical lens 100, but also can improve the resolution and imaging definition of the optical lens 100, so as to improve the shooting quality of the optical lens 100 and realize clear imaging; meanwhile, the optical lens 100 has a larger image plane and a larger aperture, so that the optical lens 100 can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens 100 can be effectively improved, meanwhile, enough light flux can be provided, the dim light shooting condition is improved, the shot picture is more vivid, and the shooting requirement of high image quality and high definition is met. 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, where the electronic device 300 includes a housing 301 and the camera module 200 as described above, and the camera module 200 is disposed on the housing 301 to obtain image information. The electronic device 300 may be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a smart watch, a monitor, and the like. It can be understood that the electronic device 300 having the camera module 200 also has all the technical effects of the optical lens 100. That is, the electronic device 300 can not only improve the painting quality of the optical lens 100 and improve the resolution and the imaging definition of the optical lens 100 while the optical lens 100 satisfies the light, thin and miniaturized design, so as to improve the shooting quality of the optical lens 100 and realize clear imaging; meanwhile, the optical lens 100 has a larger image plane and a larger aperture, so that the optical lens 100 can better match with a photosensitive chip with higher pixels, the imaging quality of the optical lens 100 can be effectively improved, meanwhile, enough light flux can be provided, the dim light shooting condition is improved, the shot picture is more vivid, and the shooting requirement of high image quality and high definition is met. Since the above technical effects have been described in detail in the embodiments of the optical lens 100, they are not described herein again.

The optical lens, the camera module and the electronic device 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 electronic device 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 includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, which are arranged in order from an object side to an image side along an optical axis;

the third lens element with refractive power;

the fourth lens element with refractive power;

the fifth lens element with refractive power;

the optical lens satisfies the following relation:

3<(FNO*TTL)/IMGH<4；

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

3.6mm<EFL/tan(HFOV)<6.3mm；

wherein EFL is an effective focal length of the optical lens, and HFOV is half of a maximum field angle of the optical lens.

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

1.5<R11/R12<3；

wherein R11 is a radius of curvature of an object-side surface of the sixth lens element at an optical axis, and R12 is a radius of curvature of an image-side surface of the sixth lens element at the optical axis.

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

4<(CT1+CT2+CT3+CT4)/CT1<7.5；

wherein CT1 is an axial thickness of the first lens element, CT2 is an axial thickness of the second lens element, CT3 is an axial thickness of the third lens element, and CT4 is an axial thickness of the fourth lens element.

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

1.7<AAG/Gmax<2.8；

wherein AAG is a sum of air gaps on an optical axis between adjacent two of the first to sixth lenses, and Gmax is a maximum air gap among the air gaps on the optical axis between adjacent two of the first to sixth lenses.

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

0.4<f2/f123<2.5；

wherein f2 is the focal length of the second lens, and f123 is the combined focal length of the first lens, the second lens and the third lens.

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

0.2<SD11/IMGH<0.4；

wherein SD11 is the maximum effective half aperture of the object side surface of the first lens.

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

0.4< | (SAG1-SAG2)/SAG1| < 0.9; and/or

2<|f1/EFL|<3.5；

SAG1 is a distance on an optical axis from an intersection point of an object side surface and an optical axis of the first lens to a maximum effective radius of the object side surface of the first lens, SAG2 is a distance on the optical axis from an intersection point of an image side surface and the optical axis of the first lens to the maximum effective radius of the image side surface of the first lens, f1 is a focal length of the first lens, and EFL is an effective focal length 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 electronic device, comprising a housing and the camera module of claim 9, wherein the camera module is disposed in the housing.