WO2022052018A1

WO2022052018A1 - Optical system, camera module, and electronic device

Info

Publication number: WO2022052018A1
Application number: PCT/CN2020/114669
Authority: WO
Inventors: 李明; 邹海荣
Original assignee: 欧菲光集团股份有限公司; 南昌欧菲精密光学制品有限公司
Priority date: 2020-09-11
Filing date: 2020-09-11
Publication date: 2022-03-17

Abstract

An optical system (100), a camera module (200), and an electronic device (30). The optical system (100) comprises a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4), a fifth lens (L5), a sixth lens (L6), a seventh lens (L7), and an eighth lens (L8) that are sequentially arranged from an object side to an image side along the direction of an optical axis; the first lens (L1) has positive refractive power, the object side surface (S1) of the first lens (L1) is a convex surface at the optical axis, and the image side surface (S2) of the first lens (L1) is a concave surface at the optical axis; the second lens (L2) has negative refractive power, the object side surface (S3) of the second lens (L2) is a convex surface at the optical axis, and the image side surface (S4) of the second lens (L2) is a concave surface at the optical axis; the eighth lens (L8) has negative refractive power, and the object side surface (S15) of the eighth lens (L8) is a concave surface at the optical axis; and the optical system (100) satisfies the following relation expression: |f12/f78|<2.

Description

Optical systems, camera modules and electronic equipment

technical field

The present application relates to the technical field of optical imaging, and in particular, to an optical system, a camera module and an electronic device.

Background technique

In recent years, with the advancement of the technology industry and the continuous development of imaging technology, the optical system of optical imaging is widely used in terminals such as smartphones, tablets, imaging, sensing, security, 3D recognition, and automation equipment. The imaging quality requirements of end products are also getting higher and higher. At present, the technology of the five-piece imaging lens group is relatively mature, but the resolution is increasingly unable to meet the needs of consumers. On the other hand, the performance of photosensitive elements such as photocoupler CCD and CMOS has been improved, which reduces the size of the photosensitive element and increases the number of pixels, which provides the possibility of shooting high-quality images and brings people higher image quality. Sensational shooting experience. Therefore, an optical system with high imaging quality is required for use in end products, so as to improve the image quality, resolution and sharpness of the photographed object.

SUMMARY OF THE INVENTION

In view of this, it is necessary to provide an optical system, a camera module and an electronic device with better imaging quality.

In a first aspect, an embodiment of the present application provides an optical system, including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a first lens, a second lens, a third lens, a fourth lens, a fifth Six lenses, a seventh lens, and an eighth lens; wherein the first lens has a positive refractive power, and the object side of the first lens is convex at the optical axis, and the image side of the first lens is at the The optical axis is concave;

The second lens has a negative refractive power, the object side of the second lens is convex at the optical axis, and the image side of the second lens is concave at the optical axis; the third lens the fourth lens has refractive power; the fifth lens has refractive power; the sixth lens has refractive power; the seventh lens has refractive power; the eighth lens has negative refractive power, And the object side of the eighth lens is concave at the optical axis; the optical system satisfies the following relationship: |f12/f78|<2; where f12 is the difference between the first lens and the second lens Combined focal length; f78 is the combined focal length of the seventh lens and the eighth lens.

In the optical system provided by the embodiments of the present application, the luminous flux of the optical system can be increased by the above-mentioned eight-piece lens structure and the refractive power configuration of each lens of the optical system, and the imaging quality under dark light shooting conditions can be improved , suitable for shooting in dark light environments such as night scenes, rainy days, and starry sky; when the above relationship f12/f78| The combined focal length of the eighth lens is conducive to correcting the high-level aberrations of the optical system and at the same time improving the performance of the optical system.

In one of the embodiments, the optical system satisfies the following relationship: f/EPD<1.7; wherein, f is the effective focal length of the optical system; and EPD is the entrance pupil diameter of the optical system. When the above relationship is satisfied, the optical system can have the characteristics of a large aperture, so that the optical system can have a larger amount of light entering and improve the shooting effect under dark conditions.

In one of the embodiments, the optical system satisfies the following relationship: f*tan(HFOV)>5.15mm; wherein, f is the effective focal length of the optical system; HFOV is the half angle of view of the optical system. When the above relationship is satisfied, the imaging of the optical system can have the characteristics of a large image plane, so that the optical system can meet the requirements of high imaging quality and high resolution.

In one of the embodiments, the optical system satisfies the following relationship: 2<|f2/f|<3; wherein, f is the effective focal length of the optical system; f2 is the effective focal length of the second lens. When the above relationship is satisfied, by adjusting the effective focal length of the second lens and the effective focal length of the optical system, the total astigmatism of the optical system can be corrected, so that the optical system can obtain good imaging quality.

In one of the embodiments, the optical system satisfies the following relationship: 1<|f/f8|<2; wherein, f is the effective focal length of the optical system; f8 is the effective focal length of the eighth lens. When the above relationship is satisfied, the weakening of the negative refractive power of the eighth lens relative to the refractive power of the optical system can be effectively controlled, thereby correcting the curvature of the imaging surface of the optical system.

In one of the embodiments, the optical system satisfies the following relationship: TTL/Imgh<1.7, where TTL is the total optical length of the optical system; ImgH is the image height corresponding to the maximum angle of view of the optical system half of . When the above relationship is satisfied, the size of the optical system can be effectively compressed, thereby realizing the ultra-thin characteristic of the optical system.

In one of the embodiments, the optical system satisfies the following relationship: 0.7mm<CT7<0.95mm; wherein, CT7 is the central thickness of the seventh lens in the optical axis direction. When the above relationship is satisfied, by adjusting the center thickness of the seventh lens, the optical system elements are easy to process, and at the same time, the optical total length of the optical system will be shortened.

In one of the embodiments, the optical system satisfies the following relationship: 1.5<f1/R1<2.5; wherein, f1 is the effective focal length of the first lens; R1 is the object side of the first lens at the optical axis the radius of curvature. When the above relationship is satisfied, the sensitivity of the optical system can be effectively reduced by adjusting the effective focal length of the first lens and the radius of the curved surface of the object side surface of the first lens.

In one of the embodiments, the optical system satisfies the following relationship: 1<(R15+R16)/(R15-R16)<3; wherein, R15 is the radius of curvature of the object side of the eighth lens at the optical axis ; R16 is the radius of curvature of the image side surface of the eighth lens at the optical axis. When the above relationship is satisfied, the astigmatism of the optical system can be corrected by adjusting the radii of the curved surfaces of the object side surface of the eighth lens and the image side surface of the eighth lens.

In a second aspect, an embodiment of the present application provides a camera module, including the optical system of any one of the above-mentioned embodiments and an image sensor, wherein the image sensor is disposed on the image side of the optical system.

In the camera module provided in the embodiment of the present application, since the optical system of any one of the above-mentioned embodiments is adopted, the same technical effect is also obtained.

In a third aspect, an embodiment of the present application provides an electronic device, including a casing and the camera module of the above-mentioned embodiment, wherein the camera module is disposed in the casing.

In the electronic device provided in the embodiment of the present application, the above-mentioned camera module is adopted, and the same technical effect is also obtained.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application or related technologies more clearly, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only the For the embodiments of the application, for those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without any creative effort.

FIG. 1 is a schematic structural diagram of an optical system provided by a first embodiment of the present application.

FIG. 2 is a ray spherical aberration diagram (mm), an astigmatism diagram (mm) and a distortion diagram (%) of the optical system in the first embodiment.

FIG. 3 is a schematic structural diagram of an optical system provided by a second embodiment of the present application.

4 is a graph of spherical aberration of rays (mm), a graph of astigmatism (mm) and a graph of distortion (%) of the optical system in the second embodiment.

FIG. 5 is a schematic structural diagram of an optical system provided by a third embodiment of the present application.

6 is a ray spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system in the third embodiment.

FIG. 7 is a schematic structural diagram of an optical system provided by a fourth embodiment of the present application.

8 is a graph of spherical aberration of rays (mm), a graph of astigmatism (mm), and a graph of distortion (%) of the optical system in the fourth embodiment.

FIG. 9 is a schematic structural diagram of an optical system provided by a fifth embodiment of the present application.

10 is a ray spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system in the fifth embodiment.

FIG. 11 is a schematic structural diagram of an optical system provided by a sixth embodiment of the present application.

12 is a graph of spherical aberration of rays (mm), a graph of astigmatism (mm), and a graph of distortion (%) of the optical system in the sixth embodiment.

FIG. 13 is a schematic structural diagram of an optical system provided by a seventh embodiment of the present application.

14 is a graph of spherical aberration of rays (mm), a graph of astigmatism (mm), and a graph of distortion (%) of the optical system in the seventh embodiment.

FIG. 15 is a schematic diagram of a camera module provided by an embodiment of the application.

FIG. 16 is a schematic diagram of an electronic device according to an embodiment of the present application.

detailed description

In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the related drawings. The preferred embodiments of the present application are shown in the accompanying drawings. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that a thorough and complete understanding of the disclosure of this application is provided.

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "inner", "outer", "left", "right" and similar expressions used herein are for the purpose of illustration only and do not represent the only embodiment.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

According to a first aspect of the present application, an optical system is provided. Please refer to FIGS. 1 , 3 , 5 , 7 , 9 , 11 and 13 , the optical system 100 in the implementation of the present application includes a second optical system with positive refractive power that is sequentially arranged along the optical axis from the object side to the image side. A lens L1, a second lens L2 with negative refractive power, a third lens L3 with refractive power, a fourth lens L4 with refractive power, a fifth lens L5 with refractive power, a sixth lens L6 with refractive power, The seventh lens L7 with refractive power and the eighth lens L8 with negative refractive power.

The first lens L1 includes an object side S1 and an image side S2, the second lens L2 includes an object side S3 and an image side S4, the third lens L3 includes an object side S5 and an image side S6, and the fourth lens L4 includes an object side S7 and an image side S8, the fifth lens L5 includes the object side S9 and the image side S10, the sixth lens L6 includes the object side S11 and the image side S12, the seventh lens L7 includes the object side S13 and the image side S14, and the eighth lens L8 includes the object side S15 and Like the side S16. The object side S1 of the first lens L1 is convex, the image side S2 of the first lens L1 is concave; the object side S3 of the second lens L2 is convex, and the image side S4 of the second lens L2 is concave; the eighth lens L8 The object side S15 is concave. Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S3 of the second lens L2 is convex at the optical axis, and the second lens L2 is convex at the optical axis. The image side S4 of the lens L2 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the optical axis.

In some embodiments, the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , the fifth lens L5 , the sixth lens L6 , the seventh lens L7 and the eighth lens L8 of the optical system 100

Among them, there is a point on the aspheric surface that is Y in the direction of the optical axis, X is the distance from the tangent plane tangent to the intersection point in the direction of the optical axis of the aspheric surface; Y is the vertical distance between the point on the aspheric surface and the direction of the optical axis, R is the radius of curvature, k is the cone coefficient, and Ai is the i-th order aspheric coefficient. When the above conditions are satisfied, each lens of the optical system 100 can be made thinner and lighter, and at the same time, optical distortion can be reduced, the distortion of the wide-angle shooting edge can be reduced, and better imaging quality can be obtained.

In some embodiments, the materials of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 may be all Plastic, the lens made of plastic can reduce the weight of the optical system 100 and reduce the production cost.

In some embodiments, the materials of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 may be all Glass, lenses made of glass can withstand higher temperatures and have better optical properties.

In other embodiments, only the first lens L1 may be made of glass, and the other lenses may be made of plastic. In this case, the first lens L1 closest to the object side can better withstand the object side. The high ambient temperature can reduce the production cost of the optical system 100 because other lenses are made of plastic.

In some embodiments, the optical system 100 further includes a stop STO, and the stop STO can be an aperture stop and is disposed on the object side of the first lens L1. An imaging surface S19 may also be provided on the image side of the eighth lens L8, and the imaging surface S19 may be the surface of the image sensor. It can be understood that the light carrying the information of the subject can sequentially pass through the aperture STO, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 and the eighth lens L8 are finally formed on the imaging plane S19.

In some embodiments, the image side of the eighth lens L8 may further be provided with an infrared cut filter 110 . In other embodiments, the infrared cut filter 110 can also be disposed on the object side of the first lens L1. By setting the infrared cut-off filter 110, the optical system 100 can filter out infrared light to prevent the infrared light from reaching the image sensor and interfere with normal visible light imaging, thereby improving the imaging quality. It should be noted that, in some embodiments, the optical system 100 may not include the infrared cut filter 110 and the image sensor. In this case, the infrared cut filter 110 may be packaged in the optical system 100 together with the image sensor to form a camera module are set in the camera module together.

Further, the optical system 100 satisfies the following relationship: |f12/f78|<2; f12 is the combined focal length of the first lens L1 and the second lens L2; f78 is the combined focal length of the seventh lens L7 and the eighth lens L8.

In the optical system 100 provided by the embodiment of the present application, the luminous flux of the optical system 100 can be increased by the above-mentioned eight-piece lens structure and the refractive power configuration of each lens of the optical system 100, and the imaging quality under the dark light shooting condition can be improved, which is suitable for Shooting in dark light environments such as night scenes, rainy days, and starry sky; when the relationship |f12/f78|<2 is satisfied, the combined focal length of the first lens L1 and the second lens L2 and the combined focal length of the seventh lens L7 and the eighth lens L8 are reasonably allocated , which is beneficial to correct the advanced aberrations of the optical system 100 while improving the performance of the optical system 100 .

In some embodiments, the optical system 100 satisfies the following relationship: f/EPD<1.7; where f is the effective focal length of the optical system 100 ; and EPD is the entrance pupil diameter of the optical system 100 . When the above relationship is satisfied, the optical system 100 can have the characteristics of a large aperture, so that the optical system 100 can have a larger amount of light entering and improve the shooting effect under dark conditions.

In some embodiments, the optical system 100 satisfies the following relationship: f*tan(HFOV)>5.15 mm; where f is the effective focal length of the optical system 100 ; HFOV is the half-field angle of the optical system 100 . When the above relationship is satisfied, the imaging of the optical system 100 can have the characteristics of a large image plane, so that the optical system 100 can meet the requirements of imaging quality, high pixels and high definition.

In some embodiments, the optical system 100 satisfies the following relationship: 2<|f2/f|<3; wherein, f is the effective focal length of the optical system 100; and f2 is the effective focal length of the second lens L2. When the above relationship is satisfied, by adjusting the effective focal length of the second lens L2 and the effective focal length of the optical system 100 , the total astigmatism of the optical system 100 can be corrected, so that the optical system 100 can obtain good imaging quality.

In some embodiments, the optical system 100 satisfies the following relationship: 1<|f/f8|<2; where f is the effective focal length of the optical system 100; and f8 is the effective focal length of the eighth lens L8. When the above relationship is satisfied, the negative power of the eighth lens L8 can be effectively controlled relative to the weakening of the power of the optical system 100 , thereby correcting the curvature of the imaging surface of the optical system 100 .

In some embodiments, the optical system 100 satisfies the following relationship: TTL/Imgh<1.7, where TTL is the total optical length of the optical system 100 ; ImgH is half of the image height corresponding to the maximum field angle of the optical system 100 . When the above relationship is satisfied, the size of the optical system 100 can be effectively compressed, thereby realizing the ultra-thin characteristic of the optical system 100 .

In some embodiments, the optical system 100 satisfies the following relationship: 0.7mm<CT7<0.95mm; wherein CT7 is the central thickness of the seventh lens L7 in the optical axis direction. When the above relationship is satisfied, by adjusting the center thickness of the seventh lens L7, the components of the optical system 100 can be easily processed, and the total optical length of the optical system 100 will be shortened.

In some embodiments, the optical system 100 satisfies the following relationship: 1.5<f1/R1<2.5; wherein, f1 is the effective focal length of the first lens L1; R1 is the radius of curvature of the object side of the first lens L1 at the optical axis. When the above relationship is satisfied, the sensitivity of the optical system 100 can be effectively reduced by adjusting the effective focal length of the first lens L1 and the radius of the curved surface of the object side surface of the first lens L1.

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

1<(R15+R16)/(R15-R16)<3; wherein, R15 is the radius of curvature of the object side S15 of the eighth lens L8 at the optical axis; R16 is the radius of curvature of the image side S16 of the eighth lens L8 at the optical axis. Radius of curvature. When the above relationship is satisfied, the astigmatism of the optical system 100 can be corrected by adjusting the radii of the curved surfaces of the object side surface S15 of the eighth lens L8 and the image side surface S16 of the eighth lens L8.

first embodiment

As shown in FIG. 1 , in the first embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a positive refractive power, and the fourth lens L4 has a positive refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is convex at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a negative refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the optical system 100 provided by the embodiment of the present application, the luminous flux of the optical system 100 can be increased by the above-mentioned eight-piece lens structure and the refractive power configuration of each lens of the optical system 100, and the imaging quality under the dark light shooting condition can be improved, which is suitable for Shooting in dark environments such as night scenes, rainy days, and starry sky.

In the first embodiment, the total effective focal length of the optical system 100 is f=6.58mm, the aperture number FNO=1.66, the field angle FOV=76.45 degrees, and the total optical length of the optical system 100 TTL=8.6mm.

In addition, each parameter of the optical system 100 is given by Table 1 and Table 2. Among them, the elements from the object side to the image side are arranged in the order of the elements from the top to the bottom in Table 1. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 1 is the curvature radius of the object side or image side of the corresponding surface number at the optical axis. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 2 is a table of relevant parameters of the aspheric surfaces of the lenses in Table 1, where k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

Table 1

Table 2

Further, please refer to FIG. 2(A), FIG. 2(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the first embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 2(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 2(B), FIG. 2(B) is a light astigmatism diagram at a wavelength of 555 nm in the first embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 2(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 2(C), FIG. 2(C) is a distortion curve diagram at a wavelength of 555 nm in the first embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 2(C) that the distortion of the optical system 100 is well corrected.

Second Embodiment

As shown in FIG. 3 , in the second embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a positive refractive power, and the fourth lens L4 has a positive refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is convex at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is convex at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a negative refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the second embodiment, the total effective focal length of the optical system 100 is f=6.53mm, the aperture number FNO=1.66, the field angle FOV=77.14 degrees, and the total optical length of the optical system 100 TTL=8.6mm.

In addition, various parameters of the optical system 100 are given in Table 3 and Table 4. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 3. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 3 is the curvature radius of the object side or image side of the corresponding surface number at the optical axis. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 4 is a table of relevant parameters of the aspheric surfaces of each lens in Table 3, wherein k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

table 3

Table 4

Further, please refer to FIG. 4(A), FIG. 4(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the second embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 2(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 4(B), FIG. 4(B) is a light astigmatism diagram at a wavelength of 555 nm in the second embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 4(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 4(C), FIG. 4(C) is a distortion curve diagram at a wavelength of 555 nm in the second embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 4(C) that the distortion of the optical system 100 is well corrected.

Third Embodiment

As shown in FIG. 5 , in the third embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a positive refractive power, and the fourth lens L4 has a positive refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is concave at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a positive refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the third embodiment, the total effective focal length of the optical system 100 is f=6.64 mm, the aperture number FNO=1.66, the field angle FOV=76 degrees, and the total optical length of the optical system 100 TTL=8.6 mm.

In addition, each parameter of the optical system 100 is given by Table 5 and Table 6. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 5. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 5 is the curvature radius of the object side or image side at the optical axis of the corresponding surface number. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 6 is a table of relevant parameters of the aspheric surfaces of each lens in Table 5, wherein k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

table 5

Table 6

Further, please refer to FIG. 6(A) . FIG. 6(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the third embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 6(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 6(B), FIG. 6(B) is a light astigmatism diagram at a wavelength of 555 nm in the third embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 6(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 6(C), FIG. 6(C) is a distortion curve diagram at a wavelength of 555 nm in the third embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 6(C) that the distortion of the optical system 100 is well corrected.

Fourth Embodiment

As shown in FIG. 7 , in the fourth embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is convex at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has a negative refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is concave at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a negative refractive power, and the fourth lens L4 has a negative refractive power. The object side S7 is convex at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is concave at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a negative refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the fourth embodiment, the total effective focal length of the optical system 100 is f=6.61 mm, the aperture number FNO=1.662, the field angle FOV=76.2 degrees, and the total optical length of the optical system 100 TTL=8.6 mm.

In addition, each parameter of the optical system 100 is given by Table 7 and Table 8. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 7. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 7 is the curvature radius of the object side or image side at the optical axis of the corresponding surface number. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 8 is a table of relevant parameters of the aspheric surfaces of each lens in Table 7, wherein k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

Table 7

Table 8

Further, please refer to FIG. 8(A), FIG. 8(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the fourth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 8(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 8(B) . FIG. 8(B) is a light astigmatism diagram at a wavelength of 555 nm in the fourth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 8(B) that the astigmatism of the optical system 100 is well compensated. Please refer to FIG. 8(C) . FIG. 8(C) is a distortion curve diagram at a wavelength of 555 nm in the fourth embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 8(C) that the distortion of the optical system 100 is well corrected.

Fifth Embodiment

As shown in FIG. 9 , in the fifth embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a negative refractive power, and the fourth lens L4 has a negative refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is concave at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a negative refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the fifth embodiment, the total effective focal length of the optical system 100 is f=6.66mm, the aperture number FNO=1.661, the field of view angle FOV=75.8 degrees, and the total optical length of the optical system 100 TTL=8.6mm.

In addition, each parameter of the optical system 100 is given by Table 9 and Table 10. Among them, the elements from the object side to the image side are arranged in the order of the elements from the top to the bottom in Table 9. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 9 is the curvature radius of the object side or image side at the optical axis of the corresponding surface number. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 10 is a table of relevant parameters of the aspheric surfaces of each lens in Table 9, where k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

Table 9

Table 10

Further, please refer to FIG. 10(A) , FIG. 10(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the fifth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 10(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 10(B), FIG. 10(B) is a light astigmatism diagram at a wavelength of 555 nm in the fifth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 10(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 10(C), FIG. 10(C) is a distortion curve diagram at a wavelength of 555 nm in the fifth embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 10(C) that the distortion of the optical system 100 is well corrected.

Sixth Embodiment

As shown in FIG. 11 , in the sixth embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a negative refractive power, and the fourth lens L4 has a negative refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is concave at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has a positive refractive power, the object side S9 of the fifth lens L5 is convex at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has a positive refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is concave at the circumference, and the image side S12 of the sixth lens L6 is convex at the circumference; the seventh lens L7 has a negative refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the sixth embodiment, the total effective focal length of the optical system 100 is f=6.67 mm, the aperture number FNO=1.66, the field angle FOV=75.66 degrees, and the total optical length of the optical system 100 TTL=8.6 mm.

In addition, each parameter of the optical system 100 is given by Table 11 and Table 12. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 11. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 11 is the curvature radius of the object side or image side of the corresponding surface number at the optical axis. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 12 is a table of relevant parameters of the aspheric surfaces of each lens in Table 11, wherein k is the cone coefficient, and Ai is the i-th order aspheric coefficient.

Table 11

Table 12

Further, please refer to FIG. 12(A), FIG. 12(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the sixth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 12(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 12(B), FIG. 12(B) is a light astigmatism diagram at a wavelength of 555 nm in the sixth embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 12(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 12(C), FIG. 12(C) is a distortion curve diagram at a wavelength of 555 nm in the sixth embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 12(C) that the distortion of the optical system 100 is well corrected.

Seventh Embodiment

As shown in FIG. 13 , in the seventh embodiment, the optical system 100 includes a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, and a The third lens L3 with refractive power, the fourth lens L4 with refractive power, the fifth lens L5 with refractive power, the sixth lens L6 with refractive power, the seventh lens L7 with refractive power, the sixth lens with negative refractive power Eight lens L8.

Specifically, the object side S1 of the first lens L1 is convex at the optical axis, the image side S2 of the first lens L1 is concave at the optical axis; the object side S1 of the first lens L1 is convex at the circumference, and the first lens L1 is convex at the circumference. The image side S2 of L1 is concave at the circumference; the object side S3 of the second lens L2 is convex at the optical axis, and the image side S4 of the second lens L2 is concave at the optical axis; the object side S3 of the second lens L2 is at The circumference is convex, the image side S4 of the second lens L2 is concave at the circumference; the third lens L3 has positive refractive power, the object side S5 of the third lens L3 is convex at the optical axis, and the image side of the third lens L3 S6 is convex at the optical axis; the object side S5 of the third lens L3 is concave at the circumference, and the image side S6 of the third lens L3 is convex at the circumference; the fourth lens L4 has a negative refractive power, and the fourth lens L4 has a negative refractive power. The object side S7 is concave at the optical axis, the image side S8 of the fourth lens L4 is convex at the optical axis; the object side S7 of the fourth lens L4 is concave at the circumference, and the image side S8 of the fourth lens L4 is at the circumference. The fifth lens L5 has negative refractive power, the object side S9 of the fifth lens L5 is concave at the optical axis, and the image side S10 of the fifth lens L5 is concave at the optical axis; the object side S9 of the fifth lens L5 It is concave at the circumference, the image side S10 of the fifth lens L5 is convex at the circumference; the sixth lens L6 has negative refractive power, the object side S11 of the sixth lens L6 is concave at the optical axis, and the image of the sixth lens L6 is concave. The side S12 is convex at the optical axis; the object side S11 of the sixth lens L6 is concave at the circumference, and the image side S12 of the sixth lens L6 is concave at the circumference; the seventh lens L7 has a positive refractive power, and the seventh lens L7 The object side S13 of the seventh lens L7 is convex at the optical axis, and the image side S14 of the seventh lens L7 is concave at the optical axis; the object side S13 of the seventh lens L7 is concave at the circumference, and the image side S14 of the seventh lens L7 is concave at the circumference. The object side S15 of the eighth lens L8 is concave at the optical axis, and the image side S16 of the eighth lens L8 is concave at the optical axis; the object side S15 of the eighth lens L8 is concave at the circumference, and the eighth lens L8 is concave. The image side surface S16 of the lens L8 is convex at the circumference.

In the seventh embodiment, the total effective focal length of the optical system 100 is f=6.69 mm, the aperture number FNO=1.65, the field angle FOV=76.6 degrees, and the total optical length of the optical system 100 TTL=8.57 mm.

In addition, each parameter of the optical system 100 is given by Table 13 and Table 14. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 13. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens. For example, surface numbers 1 and 2 correspond to the object side S1 and the image side of the first lens L1 respectively. S2. The radius in Table 13 is the curvature radius of the object side or image side of the corresponding surface number at the optical axis. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens in the direction of the optical axis (central thickness), and the second value is the image side of the lens to the object side of the following lens. distance in the direction of the axis. The value of the diaphragm in the "Thickness" parameter column is the distance from the diaphragm to the vertex of the object side of the next lens (the vertex refers to the intersection of the lens and the optical axis) in the direction of the optical axis. By default, the object side of the first lens is to the last lens. The direction of the image side of the lens is the positive direction of the optical axis direction. When the value is negative, it means that the diaphragm is set on the right side of the vertex of the object side of the latter lens. Left side of the vertex on the object side of the lens. Table 14 is a table of relevant parameters of the aspheric surfaces of the lenses in Table 13, where k is the cone coefficient and Ai is the i-th order aspheric coefficient.

Table 13

Table 14

Further, please refer to FIG. 14(A), FIG. 14(A) is a graph of spherical aberration of light at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm in the seventh embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from FIG. 14(A) that the corresponding spherical aberration values at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm are better, indicating that the imaging quality of the optical system 100 in this embodiment is better.

Please refer to FIG. 14(B), FIG. 14(B) is a light astigmatism diagram at a wavelength of 555 nm in the seventh embodiment. The abscissa along the X-axis direction represents the focus shift, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 14(B) that the astigmatism of the optical system 100 is well compensated.

Please refer to FIG. 14(C), FIG. 14(C) is a distortion curve diagram at a wavelength of 555 nm in the seventh embodiment. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height. It can be seen from FIG. 14(C) that the distortion of the optical system 100 is well corrected.

Further, the data values in each relational expression satisfied by the optical system 100 in the above seven embodiments are shown in Table 15 below.

Table 15

According to a second aspect of the present application, a camera module 200 is provided, and the camera module 200 includes the above-mentioned optical system 100 and an image sensor 210 , and the image sensor 210 is disposed on the image side of the optical system 100 , which is not described here. Do repeat. It can be understood that the camera module 200 having the above-mentioned optical system 100 also has all the technical effects of the above-mentioned optical system 100. Through the above-mentioned eight-piece lens structure and the configuration of the refractive power of each lens of the optical system 100, the above-mentioned The luminous flux of the optical system 100 improves the imaging quality under dark light shooting conditions, and is suitable for shooting in dark light environments such as night scenes, rainy days, and starry sky; when the above relationship is satisfied, parameters such as the focal length and thickness of each lens of the optical system 100 can be adjusted reasonably , which is beneficial to correct the high-level aberrations of the optical system 100 , achieve the effects of high image quality and high definition, and realize the ultra-thin characteristics of the optical system 100 . Since the above technical effects have been described in detail in the embodiment of the optical system 100 , they will not be repeated here.

According to a third aspect of the present application, an electronic device 30 is provided. The electronic device 30 includes a housing 310 and the above-mentioned camera module 200 . The electronic device 30 may be a mobile phone, a computer, a tablet, a monitor, and the like. It can be understood that the electronic device 30 having the above-mentioned camera module 200 also has all the technical effects of the above-mentioned optical system 100 . The luminous flux of the optical system 100 improves the imaging quality under dark light shooting conditions, and is suitable for shooting in dark light environments such as night scenes, rainy days, and starry sky; when the above relationship is satisfied, the parameters such as the focal length and thickness of each lens of the optical system 100 can be adjusted reasonably , which is beneficial to correct the high-level aberrations of the optical system 100 , achieve the effects of high image quality and high definition, and realize the ultra-thin characteristics of the optical system 100 . Since the above technical effects have been described in detail in the embodiment of the optical system 100 , they will not be repeated here.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

Claims

An optical system, characterized in that it includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens that are arranged in sequence from the object side to the image side along the optical axis direction , the eighth lens,

The first lens has a positive refractive power, and the object side of the first lens is convex at the optical axis, and the image side of the first lens is concave at the optical axis;

The second lens has a negative refractive power, and the object side of the second lens is convex at the optical axis, and the image side of the second lens is concave at the optical axis;

the third lens has refractive power;

the fourth lens has refractive power;

the fifth lens has refractive power;

the sixth lens has refractive power;

the seventh lens has refractive power;

the eighth lens has negative refractive power, and the object side of the eighth lens is concave at the optical axis;

The optical system satisfies the following relationship:

|f12/f78|<2;

Wherein, f12 is the combined focal length of the first lens and the second lens; f78 is the combined focal length of the seventh lens and the eighth lens.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

f/EPD<1.7;

Wherein, f is the effective focal length of the optical system; EPD is the entrance pupil diameter of the optical system.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

f*tan(HFOV)>5.15mm;

Wherein, f is the effective focal length of the optical system; HFOV is the half angle of view of the optical system.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

2<|f2/f|<3;

Wherein, f is the effective focal length of the optical system; f2 is the effective focal length of the second lens.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

1<|f/f8|<2;

Wherein, f is the effective focal length of the optical system; f8 is the effective focal length of the eighth lens.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

TTL/Imgh<1.7

Wherein, TTL is the total optical length of the optical system; ImgH is half of the image height corresponding to the maximum angle of view of the optical system.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

0.7mm<CT7<0.95mm;

Wherein, CT7 is the central thickness of the seventh lens in the optical axis direction.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

1.5<f1/R1<2.5;

Wherein, f1 is the effective focal length of the first lens; R1 is the radius of curvature of the object side of the first lens at the optical axis.
The optical system according to claim 1, wherein the optical system satisfies the following relationship:

1<(R15+R16)/(R15-R16)<3;

Wherein, R15 is the radius of curvature of the object side of the eighth lens at the optical axis; R16 is the radius of curvature of the image side of the eighth lens at the optical axis.
A camera module, characterized in that it comprises the optical system according to any one of claims 1-9 and an image sensor, wherein the image sensor is arranged on the image side of the optical system.
An electronic device, comprising a casing and the camera module according to claim 10, wherein the camera module is arranged in the casing.