WO2021003714A1 - Optical imaging system and electronic device - Google Patents

Abstract

Embodiments of the present invention provide an optical imaging system and an electronic device. The optical imaging system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens disposed in sequence from an object side to an image side. The first lens and the sixth lens have negative refractive power, and the second lens, the third lens, the fourth lens, and the fifth lens have positive refractive power. Each of the first lens, the second lens, the fourth lens, and the sixth lens has a convex object-side surface and a concave image-side surface. Each of the third lens and the fifth lens has a concave object-side surface and a convex image-side surface. At least one of the object-side surface and the image-side surface of the sixth lens comprises at least one inflection point. The optical imaging system in the embodiments of the invention meets the requirements of miniaturization.

Description

Optical imaging system and electronic device Technical field

The embodiment of the present invention relates to the field of optical imaging technology, and in particular to an optical imaging system and an electronic device.

Background technique

In recent years, with the development of science and technology, portable electronic products have gradually emerged, and camera lens products with miniaturized, high-pixel and large aperture have been favored by more people.

In order to meet the requirements of miniaturization, currently available lenses on the market are usually equipped with a fixed aperture to achieve miniaturization while having good optical performance. However, with the continuous development of smart electronic products, higher requirements are put forward for imaging lenses, especially for different environments and different scenes, the requirements for the depth of field of the lens vary greatly, so the fixed aperture cannot meet the higher-end lens requirements.

At present, miniaturized lenses on the market use VCM (Voice Coil Motor) for overall focus. During the VCM overall focus process, when the lens shakes greatly, the screen will shake, and the overall focus will cause the overall weight to be too large. , Is not conducive to focusing speed and module miniaturization.

Summary of the invention

The invention provides an optical imaging system and an electronic device.

According to an aspect of the embodiments of the present invention, there is provided an optical imaging system, which includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens sequentially arranged from the object side to the image side . Wherein, the first lens and the sixth lens have negative refractive power, the second lens, the third lens, the fourth lens, and the fifth lens have positive refractive power, and the first lens The lens, the second lens, the fourth lens, and the sixth lens have a convex object side surface and a concave image side surface, and the third lens and the fifth lens have a concave object side surface and It is a convex image side surface, and at least one of the object side surface and the image side surface of the sixth lens includes at least one inflection point.

According to another aspect of the embodiments of the present invention, there is provided an electronic device including the optical imaging system and a photosensitive element as described above, wherein the photosensitive element is arranged on the image side of the optical imaging system.

The embodiment of the present invention allows the optical imaging system to meet the requirements of miniaturization of the lens by reasonably setting the six lenses in the optical imaging system, which is beneficial to the miniaturization of products.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

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

2 is a chromatic aberration distribution diagram at the inf position of the optical imaging system according to an embodiment of the present invention;

3 is a chromatic aberration distribution diagram of the MOD position of the optical imaging system according to the embodiment of the present invention;

4 is a diagram of inf field curvature and distortion of the optical imaging system according to an embodiment of the present invention;

5 is a diagram of MOD field curvature and distortion of the optical imaging system according to an embodiment of the present invention;

6 is an inf-phase contrast distribution diagram of the optical imaging system according to an embodiment of the present invention;

FIG. 7 is a MOD relative illuminance distribution diagram of an optical imaging system according to an embodiment of the present invention;

FIG. 8 is a distribution diagram of inf magnification chromatic aberration of an optical imaging system according to an embodiment of the present invention;

FIG. 9 is a chromatic aberration distribution diagram of MOD magnification of an optical imaging system according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Here, exemplary embodiments will be described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings indicate the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present invention. Rather, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

The terms used in the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and/or" as used herein refers to and includes any or all possible combinations of one or more of the associated listed items. Unless otherwise indicated, similar words such as "front", "rear", "lower" and/or "upper" are only for convenience of description, and are not limited to one position or one spatial orientation. Similar words such as "connected" or "connected" are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect. In the present invention, "ability" can mean having ability.

The various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the case of no conflict, the following embodiments and features in the implementation can be combined with each other.

FIG. 1 is a schematic structural diagram of an embodiment of an optical imaging system according to an embodiment of the present invention. As shown in FIG. 1, the optical imaging system 100 of the embodiment of the present invention includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a The sixth lens L6, wherein the first lens L1 has negative refractive power, the object side S11 of the first lens L1 is convex, and the image side S12 is concave; the second lens L2 has positive refractive power, and the object side of the second lens L2 S21 is a convex surface, the image side surface S22 is concave; the third lens L3 has positive refractive power, the object side surface S31 of the third lens L3 is concave, and its image side surface S32 is convex; the fourth lens L4 has positive refractive power, the fourth lens The object side surface S41 of L4 is convex, and the image side surface S42 is concave; the fifth lens L5 has positive refractive power, the object side S51 of the fifth lens L5 is concave, and the image side surface S52 is convex; the sixth lens L6 has negative refractive power The object side surface S61 of the sixth lens L6 is a convex surface, and the image side surface S62 is a concave surface, and at least one of the object side surface S61 and the image side surface S62 of the sixth lens L6 includes at least one inflection point.

It should be noted that the shapes of the surface of the lens mentioned in this article represent these shapes relative to the optical axis O of the lens. For example, if the object side or image side of the lens is convex, it means that the optical axis of the corresponding surface is convex. If the object or image side of the lens is concave, it means that the optical axis of the corresponding surface is concave. It does not limit the corresponding surface. The shape of the edge of the surface. Therefore, in a configuration in which one surface of the lens is described as a convex surface, the edge portion of the surface of the lens may be a concave surface. In other words, the paraxial region of the surface of the lens is a convex surface, and the rest of the lens outside the paraxial region may be a convex, concave or flat surface. Similarly, in a configuration where one surface of the lens is described as a concave surface, the edge portion of the surface of the lens may be a convex surface. In other words, the paraxial region of the lens is a concave surface, and the rest of the lens outside the paraxial region can be a convex surface, a concave surface or a flat surface.

According to the optical imaging system 100 of the embodiment of the present invention, the optical imaging system 100 not only meets the requirement of miniaturization, but also meets the requirement of high resolution through the reasonable setting of the above six lenses.

In some embodiments, both the object side surface S61 and the image side surface S62 of the sixth lens L6 include at least one inflection point, which can effectively suppress the angle of the off-axis field of view light incident on the photosensitive element, thereby correcting the off-axis The aberration of the field of view improves the image quality.

Continuing to refer to FIG. 1, the optical imaging system 100 according to the embodiment of the present invention includes a filter L7. For example, the filter L7 may be located between the sixth lens L6 and the imaging surface S0. The filter L7 as described above can filter the infrared rays incident on the imaging surface S0. However, no matter how suitable it is, in other embodiments, light of other frequencies can also be filtered out.

When the optical imaging system 100 is used for imaging, the light emitted or reflected by the subject enters the optical imaging system 100 from the object side direction, and sequentially passes through the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4. , The fifth lens L5, the sixth lens L6 and the filter L7, and finally converge on the imaging surface S0.

In some embodiments, the optical imaging system 100 satisfies the following conditions:

0.4<f/TTL<0.6

Where, f is the effective focal length of the optical imaging system 100, and TTL is the distance on the optical axis O from the object side of the first lens L1 to the imaging surface S0.

In an embodiment of the present invention, the optical imaging system 100 includes a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 includes a first lens L1 and a second lens L2. The lens group G2 includes a third lens L3 and a fourth lens L4, the third lens group G3 includes a fifth lens L5 and a sixth lens L6, and the third lens group G3 is a focusing group. The third lens group G3 is used to focus, which can converge the light in a shorter distance to achieve focus and make the lens more compact.

The optical imaging system 100 of the embodiment of the present invention adopts partial focusing, which can meet the requirement that the lens has better performance at the macro end. Moreover, compared with the overall focusing, the partial focusing can effectively reduce the weight of the focusing group, so that the The lighter weight also enables the overall module to meet the miniaturization, and is conducive to fast focusing.

In some embodiments, the optical imaging system 100 further includes a stop ST, which is located between the first lens group G1 and the second lens group G2. The stop ST may be an aperture stop or a field stop. In the embodiment of the present invention, the diaphragm ST is an aperture diaphragm as an example for description.

In one embodiment, the diaphragm ST may be a variable diaphragm. In another embodiment, the stop ST may also be a fixed aperture.

In some embodiments, the optical imaging system 100 satisfies the following conditions:

0.1<fsL2/fsL1<0.6

Among them, fsL1 is the focal length of the first lens group G1, and fsL2 is the focal length of the second lens group G2.

If the above conditions are met, the optical imaging system 100 of the embodiment of the present invention may adopt a fixed aperture.

In some embodiments, the optical imaging system 100 satisfies the following conditions:

0.2<f/fsL3<1.0

Among them, f is the effective focal length of the optical imaging system 100, and fsL3 is the focal length of the third lens group G3.

The optical imaging system 100 of the embodiment of the present invention uses the third lens group G3 as the focusing group, and when the above conditions are met, focusing at different object distances can be effectively achieved.

In some embodiments, the first lens L1 satisfies the following conditions:

0.25<|(R11-R12)/(R11+R12)|<0.35

Among them, R11 is the radius of curvature of the object side S11 of the first lens L1, and R12 is the radius of curvature of the image side S12 of the first lens L1.

When the above conditions are met, the distortion can be effectively eliminated, and the optical imaging system 100 has a better flat field curvature ability.

In one embodiment, the image side surface S12 of the first lens L1 and the object side surface S21 of the second lens L2 have substantially the same radius of curvature, so that the sensitivity of the lens lens can be reduced, and aberrations can be further suppressed. assembly.

In another embodiment, the second lens L2 satisfies the following conditions:

0<|(R12-R21)/(R21+R12)|<0.1

Among them, R12 is the radius of curvature of the image side surface S12 of the first lens L1, and R21 is the radius of curvature of the object side surface S21 of the second lens L2.

When the above conditions are met, aberrations can be suppressed, and at the same time, the sensitivity of the lens and lens can be reduced, and the assembly of the lens and lens can be facilitated.

In some embodiments, the third lens L3 satisfies the following conditions:

1.49<nd3≤1.7

Among them, nd3 is the refractive index of the material of the third lens L3.

When the above conditions are met, off-axis aberrations can be effectively improved. In addition, due to the requirement of miniaturization of the lens, the total length of the lens is very short, so setting such a high refractive index is beneficial to quickly change the light direction, and achieve the purpose of matching the chief light angle (CRA, Chief Ray Angle) defined by the photosensitive element.

In an embodiment, the material of the third lens L3 may be glass. In another embodiment, the third lens L3 is aspherical.

In some embodiments, the refractive index of the material of fourth lens L4 satisfies the following conditions:

1.58<nd4≤1.8.

Wherein, nd4 is the refractive index of the material of the fourth lens L4.

When the above conditions are met, the off-axis aberration can be effectively improved, and at the same time, it is beneficial to correct the angle of the lens, and can better match the photosensitive element.

In one embodiment, the material of fourth lens L4 is glass. In another embodiment, the fourth lens L4 is aspherical.

In some embodiments, the fifth lens L5 satisfies the following conditions:

0.2≤T56/(CT5+CT6)≤0.6

Among them, T56 is the air space between the image side surface S52 of the fifth lens L5 and the object side surface S61 of the sixth lens L6, CT5 is the central thickness of the fifth lens L5, and CT6 is the central thickness of the sixth lens L6.

When the above conditions are met, the specular reflection before the fifth lens L5 and the sixth lens L6 can be effectively improved, and ghost images can be effectively suppressed.

In some embodiments, the sixth lens L6 satisfies the following conditions:

0.3<|f6/f|<1.9

Among them, f6 is the focal length of the sixth lens L6, and f is the effective focal length of the optical imaging system 100.

When the above conditions are met, it can contribute to the miniaturization of the lens.

The optical imaging system 100 of the embodiment of the present invention may adopt a glass-plastic hybrid design. In some embodiments of the present invention, the materials of the first lens L1, the second lens L2, the fifth lens L5, and the sixth lens L6 are plastic, and the materials of the third lens L3 and the fourth lens L4 are glass. Thus, the weight of the lens can be further reduced, which is more conducive to the miniaturization of the lens.

The data of each surface of the lens of the optical imaging system of an embodiment of the present invention is shown in Table 1. In Table 1, the unit of the radius of curvature and the thickness is mm, where the surface 1-17 indicates each surface from the object side to the image side in turn, and the surface 1-15 indicates the object side of the first lens and the first lens in turn. The image side, the object side of the second lens, the image side of the second lens, the diaphragm, the object side of the third lens, the image side of the third lens, the object side of the fourth lens, the image side of the fourth lens, the fifth The object side of the lens, the image side of the fifth lens, the object side of the sixth lens, the image side of the sixth lens, the object side of the filter, and the image side of the filter, plane 16 represents the center compensation after paraxial solution of the lens Value, surface 17 represents the imaging surface.

Table 1

To	surface	Radius of curvature	thickness	Refractive index	Dispersion coefficient
Subject	To	unlimited	unlimited	To	To
To	1	10.30279	3.318	1.66	20.4
To	2	5.61422	0.416	To	To

To	3	5.61277	0.453	1.52	56.6
To	4	6.99808	0.722	To	To
Diaphragm	5	unlimited	1.404	To	To
To	6	-92.00956	2.402	1.55	71.7
To	7	-8.69824	1.383	To	To
To	8	5.03100	1.456	1.69	53.2
To	9	18.50085	D1	To	To
To	10	-4.99222	1.200	1.54	56.1
To	11	-3.12146	0.800	To	To
To	12	12.64424	1.863	1.66	20.4
To	13	3.50199	D2	To	To
To	14	unlimited	0.710	1.52	64.2
To	15	unlimited	1.233	To	To
To	16	unlimited	0.003	To	To
Imaging surface	17	unlimited	-	To	To

The focal length and power distribution of each lens in the embodiment of the present invention are shown in Table 2:

Table 2

lens	focal length	ability
L1	-29.38	-0.03
L2	-61.50	-0.02
L3	21.00	0.05
L4	11.72	0.09
L5	15.74	0.06
L6	-9.50	-0.11

In the embodiment of the present invention, each lens mostly adopts an aspheric mirror surface, that is, the curvature is continuously changed from the center of the lens to the periphery of the lens. Compared with a spherical lens with a constant curvature, an aspheric lens has better curvature radius characteristics, and has the advantages of improving distortion and astigmatism. After the aspheric lens is used, the aberrations that occur during imaging can be eliminated as much as possible, thereby improving the imaging quality. Optionally, at least one of the object side surface and the image side surface of each of the first lens L1 to the sixth lens L6 may be an aspheric surface. Further, the object side surface and the image side surface of each of the first lens L1 to the sixth lens L6 are both aspherical.

The aspheric coefficients of each lens in this embodiment are specifically shown in Table 3. In Table 3, K is the second-order curvature constant, and A4-A16 represent the 4-16th-order even-phase aspheric coefficients of each lens surface.

table 3

To	K	A2	A4	A6	A8	A10	A12	A14	A16
2 sides	0.906053	0	0.001237796	-3.13974E-05	1.16818E-05	1.88E-07	-4.27118E-08	2.28167E-09	-4.5E-11
3 sides	-3.647088	0	0.008324712	-0.000640803	0.000945751	0.000209	-0.000152812	3.60987E-05	-2.7E-06
4 sides	2.819467	0	0.003639762	-0.001085592	0.001273715	7.96E-05	0. 000142776	-4.16683E-05	4.78E-06
5 sides	-4.200197	0	0.001585725	-0.000151138	-0.002532032	0.002571	-0.000665257	7.64129E-05	-5.2E-07
7 sides	0	0	-0.00209196	-1.76422E-05	-7.5948E-06	-1.6E-05	1.43414E-06	0	0
8 sides	3.018815	0	-0.005042716	0.000150369	-9.14489E-05	-4.6E-06	6.57947E-07	-3.71862E-08	0
9 sides	-0.026961	0	-0.001587536	2.53102E-05	-2.13933E-05	3.61E-07	2.24162E-08	-7.80295E-10	0
10 sides	0	0	0.00133245	-7.62022E-05	7.12141E-06	3.16E-07	3.3058E-09	-3.79977E-10	0
11 sides	0	0	0.001781158	-5.97313E-05	0.000118832	-5.7E-06	1.59239E-07	-4.00612E-09	5.23E-11
12 sides	-1.183833	0	0.000109025	7.36272E-05	9.94921E-07	1.16E-06	-5.22361E-08	-4.77486E-10	1.75E-11
13 sides	0	0	-0.007981303	0.000237449	9.51205E-05	-1.1E-05	3.05632E-07	1.27407E-09	-1.1E-10
14 sides	-4.634024	0	-0.004493627	0.000219759	-6.28503E-05	8.43E-07	-4.60109E-09	5.39794E-11	-7.9E-13

2 is an inf position chromatic aberration distribution diagram of an optical imaging system according to an embodiment of the present invention; FIG. 3 is a MOD position chromatic aberration distribution diagram of an optical imaging system according to an embodiment of the present invention; FIG. 4 is an inf image of an optical imaging system according to an embodiment of the present invention Surface curvature and distortion diagram; FIG. 5 is a MOD field curvature and distortion diagram of the optical imaging system according to an embodiment of the present invention; FIG. 6 is an inf phase contrast distribution diagram of the optical imaging system according to an embodiment of the present invention; FIG. 7 is an implementation of the present invention Fig. 8 is a chromatic aberration distribution diagram of inf magnification of the optical imaging system of an embodiment of the present invention; and Fig. 9 is a chromatic aberration distribution diagram of MOD magnification of the optical imaging system of an embodiment of the present invention. Among them, inf indicates that the object distance is infinite, and MOD indicates that the object distance is the minimum distance. According to FIGS. 2-9, those skilled in the art can understand that the optical imaging system of the embodiment of the present invention has small chromatic aberration and distortion, and has excellent imaging effects.

In this document, descriptions of the terms "certain embodiments", "one embodiment", "another embodiment" or "some embodiments" etc. mean specific features, structures, materials, or conditions described in conjunction with the embodiments. Included in at least one embodiment of the present invention. In this document, the schematic representations of the above terms do not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or conditions described above in this document can be combined in any one or more embodiments in a suitable manner.

The optical imaging system 100 of the embodiment of the present invention may be applied to an electronic device. Therefore, the embodiment of the present invention may also provide an electronic device. The electronic device in the embodiment of the present invention may include, but is not limited to, a smart phone, a mobile phone, a personal digital assistant (PDA), a game console, and a personal computer (Personal Digital Assistant). Computer, PC), cameras, smart watches, tablet computers, handheld PTZ and other information terminal equipment or home appliances with camera functions, etc.

The electronic device of the embodiment of the present invention includes the optical imaging system 100 and the photosensitive element (not shown) as described in the various embodiments above, and the photosensitive element is arranged on the image side of the optical imaging system 100.

The photosensitive element may provide an imaging surface S0 on which light refracted by the lens is imaged. In addition, the photosensitive element can convert the light signal imaged on the imaging surface S0 into an electrical signal for use by a computer or other suitable electronic devices. The photosensitive element may be a Complementary Metal Oxide Semiconductor (CMOS) image sensor or a Charge-coupled Device (CCD, Charge-coupled Device) image sensor, etc.

In some embodiments, the size of the photosensitive element is greater than or equal to 1 inch.

In the electronic device of the embodiment of the present invention, the lens of the optical imaging system 100 adopts a glass-plastic hybrid design, the optical length of the lens can be less than 20 mm, and the aperture can be 2.0.

The electronic device of the embodiment of the present invention further includes a focus motor (not shown) for driving the optical imaging system 100 to focus. In some embodiments, the focus motor is an Ultra-Sonic Motor (USM).

The electronic device of the embodiment of the present invention realizes miniaturization, large aperture, variable aperture, fast focusing, and high pixel requirements on the basis of meeting the requirements of large-size photosensitive elements. Moreover, the electronic device of the embodiment of the present invention adopts partial focus, which effectively reduces the weight of the focus group, and uses the USM motor to focus while improving the problem of image shake, while also enabling the overall module to meet miniaturization.

Other beneficial technical effects of the electronic device according to the embodiment of the present invention are similar to those of the optical imaging system 100 described above, so they will not be repeated here.

It should be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these There is any such actual relationship or sequence between entities or operations. The terms "include", "include", or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. Elements, or also include elements inherent to such processes, methods, articles, or equipment. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other same elements in the process, method, article, or equipment including the element.

The optical imaging system and electronic device provided by the embodiments of the present invention are described in detail above. Specific examples are used in this article to illustrate the principles and implementation of the present invention. The description of the above embodiments is only used to help understand the present invention. The method and its core idea, the content of this specification should not be construed as a limitation of the present invention. At the same time, for those of ordinary skill in the art, based on the ideas of the present invention, any modification, equivalent replacement or improvement, etc. can be made in the specific implementation and the scope of application, which shall be included in the scope of the claims of the present invention. Inside.

Claims (32)

1. An optical imaging system, which includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side to the image side, and is characterized in that the first lens And the sixth lens have negative refractive power, the second lens, the third lens, the fourth lens, and the fifth lens have positive refractive power, the first lens and the second lens The fourth lens and the sixth lens have a convex object side surface and a concave image side surface, the third lens and the fifth lens have a concave object side surface and a convex image side surface, so At least one of the object side surface and the image side surface of the sixth lens includes at least one inflection point.
2. The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditions:

   0.4<f/TTL<0.6

   Wherein, f is the effective focal length of the optical imaging system, and TTL is the distance on the optical axis from the object side of the first lens to the imaging surface.
3. The optical imaging system according to claim 1, wherein both the object side surface and the image side surface of the sixth lens include at least one inflection point.
4. The optical imaging system of claim 1, wherein the optical imaging system includes a first lens group, a second lens group, and a third lens group, wherein the first lens group includes a first lens and a third lens group. Two lenses, the second lens group includes a third lens and a fourth lens, the third lens group includes a fifth lens and a sixth lens, and the third lens group is a focusing group.
5. The optical imaging system of claim 4, further comprising:

   The diaphragm is located between the first lens group and the second lens group.
6. The optical imaging system of claim 5, wherein the diaphragm is an iris diaphragm.
7. The optical imaging system according to claim 5, wherein the diaphragm is a fixed diaphragm.
8. 8. The optical imaging system of claim 7, wherein the optical imaging system satisfies the following conditions:

   0.1<fsL2/fsL1<0.6

   Wherein, fsL1 is the focal length of the first lens group, and fsL2 is the focal length of the second lens group.
9. The optical imaging system of claim 4, wherein the optical imaging system satisfies the following conditions:

   0.2<f/fsL3<1.0

   Wherein, f is the effective focal length of the optical imaging system, and fsL3 is the focal length of the third lens group.
10. The optical imaging system according to any one of claims 1 to 9, wherein the first lens satisfies the following conditions:

    0.25<|(R11-R12)/(R11+R12)|<0.35

    Wherein, R11 is the radius of curvature of the object side surface of the first lens, and R12 is the radius of curvature of the image side surface of the first lens.
11. 10. The optical imaging system of claim 10, wherein the image side surface of the first lens and the object side surface of the second lens have substantially the same radius of curvature.
12. The optical imaging system according to claim 10, wherein the second lens satisfies the following conditions:

    0<|(R12-R21)/(R21+R12)|<0.1

    Wherein, R12 is the radius of curvature of the image side surface of the first lens, and R21 is the radius of curvature of the object side surface of the second lens.
13. The optical imaging system of claim 12, wherein the third lens satisfies the following conditions:

    1.49<nd3≤1.7

    Wherein, nd3 is the refractive index of the material of the third lens.
14. The optical imaging system according to claim 13, wherein the material of the third lens is glass.
15. 14. The optical imaging system of claim 14, wherein the third lens is an aspheric surface.
16. The optical imaging system according to claim 13, wherein the refractive index of the material of the fourth lens satisfies the following conditions:

    1.58<nd4≤1.8.
17. The optical imaging system according to claim 16, wherein the material of the fourth lens is glass.
18. The optical imaging system according to claim 17, wherein the fourth lens is an aspheric surface.
19. The optical imaging system of claim 16, wherein the fifth lens satisfies the following conditions:

    0.2≤T56/(CT5+CT6)≤0.6

    Wherein, T56 is the air space between the image side surface of the fifth lens and the object side surface of the sixth lens, CT5 is the central thickness of the fifth lens, and CT6 is the central thickness of the sixth lens.
20. 18. The optical imaging system of claim 19, wherein the sixth lens satisfies the following conditions:

    0.3<|f6/f|<1.9

    Wherein, f6 is the focal length of the sixth lens, and f is the effective focal length of the optical imaging system.
21. The optical imaging system according to any one of claims 1 to 9, wherein the third lens satisfies the following conditions:

    1.49<nd3≤1.7

    Wherein, nd3 is the refractive index of the material of the third lens.
22. The optical imaging system of claim 21, wherein the material of the third lens is glass.
23. The optical imaging system of claim 22, wherein the third lens is an aspheric surface.
24. The optical imaging system according to claim 21, wherein the refractive index of the material of the fourth lens satisfies the following conditions:

    1.58<nd4≤1.8.
25. The optical imaging system according to claim 24, wherein the material of the fourth lens is glass.
26. The optical imaging system of claim 25, wherein the fourth lens is an aspheric surface.
27. The optical imaging system according to any one of claims 1 to 9, wherein the fifth lens satisfies the following conditions:

    0.2≤T56/(CT5+CT6)≤0.6

    Wherein, T56 is the air space between the image side surface of the fifth lens and the object side surface of the sixth lens, CT5 is the central thickness of the fifth lens, and CT6 is the central thickness of the sixth lens.
28. The optical imaging system of claim 27, wherein the sixth lens satisfies the following conditions:

    0.3<|f6/f|<1.9

    Wherein, f6 is the focal length of the sixth lens, and f is the effective focal length of the optical imaging system.
29. The optical imaging system according to any one of claims 1 to 9, wherein the material of the first lens, the second lens, the fifth lens and the sixth lens is plastic, so The material of the third lens and the fourth lens is glass.
30. An electronic device, characterized in that it comprises:

    The optical imaging system according to any one of claims 1 to 29; and

    The photosensitive element is arranged on the image side of the optical imaging system.
31. The electronic device of claim 30, wherein the size of the photosensitive element is greater than or equal to 1 inch.
32. 34. The electronic device of claim 30, further comprising: a focus motor for driving the optical imaging system to focus, and the focus motor is an ultrasonic motor.

Images