CN211698388U

CN211698388U - Optical system, camera module, electronic device and automobile

Info

Publication number: CN211698388U
Application number: CN202020333956.4U
Authority: CN
Inventors: 蔡雄宇; 兰宾利; 赵迪; 周芮
Original assignee: Tianjin OFilm Opto Electronics Co Ltd
Current assignee: Jiangxi Oufei Optics Co ltd
Priority date: 2020-03-17
Filing date: 2020-03-17
Publication date: 2020-10-16
Anticipated expiration: 2030-03-17

Abstract

The utility model relates to an optical system, module, electron device and car of making a video recording. The optical system includes in order from an object side to an image side: a first lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a second lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power; a fourth lens element with positive refractive power; a fifth lens element with positive refractive power; a sixth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; the optical system further comprises a middle diaphragm, and the optical system satisfies the relationship: f456/f < 3 > 0; wherein f456 is a combined focal length of the fourth lens element, the fifth lens element and the sixth lens element, and f is an effective focal length of the optical system. When the relation is satisfied, the miniaturization design of the system is facilitated, and meanwhile the imaging definition of the system can be improved.

Description

Optical system, camera module, electronic device and automobile

Technical Field

The utility model relates to a field of making a video recording especially relates to an optical system, module, electron device and car of making a video recording.

Background

With the development of camera devices, especially for the vehicle-mounted industry, the technical requirements of users on vehicle-mounted cameras such as forward looking cameras, automatic cruising cameras, automobile data recorders and back-up images are higher and higher. The front-view camera is a vehicle-mounted camera arranged in front of the vehicle, can be used as a camera system in an advanced driver assistance system to analyze video content and provide Lane Departure Warning (LDW), automatic Lane Keeping Assistance (LKA), high beam/low beam control and Traffic Sign Recognition (TSR); when the device is used for parking, the device is opened, so that obstacles in front of a vehicle can be seen visually, and the parking is more convenient; the front-view camera is opened at any time when the automobile passes through a special place (such as a road block, a parking lot and the like), the driving environment is judged, and a correct instruction is given by feeding back an automobile central system to avoid driving accidents. But the existing camera module has defects in the aspect of high-image-quality imaging effect, so that a driver and a system are difficult to accurately and timely judge the barrier.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is necessary to provide an optical system, an image pickup module, an electronic apparatus, and an automobile, in order to solve the problem of how to improve the image sharpness.

An optical system comprising, in order from an object side to an image side:

the lens comprises a first lens element with negative refractive power having a convex object-side surface and a concave image-side surface;

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

a third lens element with positive refractive power;

a fourth lens element with positive refractive power;

a fifth lens element with positive refractive power;

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

the optical system further comprises a middle diaphragm, and the optical system satisfies the following relation:

0＜f456/f＜3；

wherein f456 is a combined focal length of the fourth lens, the fifth lens and the sixth lens, and f is an effective focal length of the optical system. When the relationship among the refractive power, the surface shape and the conditional expressions of the lens is satisfied, the rear end lens group of the system can be ensured to provide positive refractive power for the system, so that light rays diffused through the system end are converged, the spacing distance between the fourth lens and the fifth lens is reduced, the miniaturization design of the system is facilitated, meanwhile, the sensitivity of the rear end of the system can be reduced, the generation of high-order aberration is inhibited, and the imaging definition is improved. The rear end lens group of the optical system is composed of the fourth lens, the fifth lens and the sixth lens.

In one embodiment, the object-side surface and the image-side surface of the third lens element, the fourth lens element and the fifth lens element are convex. The third lens element, the fourth lens element and the fifth lens element provide positive refractive power for the optical system to converge incident light.

In one embodiment, the optical system satisfies the following relationship:

-3＜f1/f＜0；

wherein f1 is the effective focal length of the first lens, and f is the effective focal length of the optical system. The first lens element provides negative refractive power to the optical system, and when the above relationship is satisfied, the optical system can have the characteristics of wide viewing angle, low sensitivity and miniaturization.

In one embodiment, the optical system satisfies the following relationship:

-5＜f2/f＜0；

wherein f2 is the effective focal length of the second lens, and f is the effective focal length of the optical system. The second lens provides negative refractive power for the optical system, and when the relation is met, the optical system can have a wide viewing angle, the risk of ghost image generation is reduced, and the imaging quality is improved.

In one embodiment, the optical system satisfies the following relationship:

0＜(R3+R4)/(R3-R4)＜3；

wherein R3 is a curvature radius of an object side surface of the second lens at an optical axis, and R4 is a curvature radius of an image side surface of the second lens at the optical axis. When the relation is met, the curvature radiuses of the object side surface and the image side surface of the second lens can be reasonably configured, so that the bending degree of the second lens can be effectively controlled, the processing difficulty of the second lens is reduced, the problem of uneven film coating caused by the fact that the second lens is excessively bent is avoided, meanwhile, the risk of ghost image generation can be reduced, and the resolving power of an optical system is improved.

In one embodiment, the optical system satisfies the following relationship:

1＜CT3/CT2＜5；

wherein CT2 is the thickness of the second lens element on the optical axis, and CT3 is the thickness of the third lens element on the optical axis. When the above relation is satisfied, the thicknesses of the second lens element and the third lens element can be reasonably configured, so that the refractive power of the front end of the system can be reasonably distributed, the sensitivity of the system can be reduced, the aberration can be corrected, and the resolution power of the system can be improved. The front end of the optical system is composed of the first lens, the second lens and the third lens.

In one embodiment, the optical system satisfies the following relationship:

0＜d16/CT4＜3；

wherein CT4 is the thickness of the fourth lens element on the optical axis, and d16 is the sum of the distances between the adjacent first to sixth lens elements on the optical axis. When the above relation is satisfied, the sum of the thickness of the fourth lens and the distance between each adjacent lens in the system can be effectively set, so that the total length of the optical system can be effectively controlled, the miniaturization design of the system is ensured, meanwhile, the aberration of the system is favorably corrected, and the resolution power of the system is improved.

In one embodiment, the optical system satisfies the following relationship:

0＜CT16/TTL＜1；

wherein CT16 is a sum of thicknesses of the first lens element to the sixth lens element on an optical axis, and TTL is a total optical length of the optical system. When the above relation is satisfied, the total length of the optical system can be shortened, and meanwhile, the aberration of the system can be corrected, so that the imaging quality is improved.

In one embodiment, the image side surface of the fifth lens is cemented with the object side surface of the sixth lens, and the optical system satisfies the following relationship:

-4＜R56/f56＜0；

wherein R56 is a curvature radius of a bonding surface of the fifth lens element and the sixth lens element at an optical axis, and f56 is a combined focal length of the fifth lens element and the sixth lens element. The fifth lens element and the sixth lens element provide positive refractive power for the optical system as a whole, which is beneficial to correcting aberration, and can achieve balance between reducing volume and improving resolving power.

In one embodiment, the optical system satisfies the following relationship:

(1/2)FOV*f/Imgh＞60；

wherein FOV is a maximum angle of view of the optical system, f is an effective focal length of the optical system, and Imgh is an image height corresponding to the maximum angle of view of the optical system. When the above relation is satisfied, the resolution capability of the system is improved, and therefore the pixel quality is improved.

In one embodiment, the optical system satisfies the following relationship:

Nd3-Nd2＞0；Nd6-Nd5＞0；

wherein Nd2 is a d-light refractive index of the second lens, Nd3 is a d-light refractive index of the third lens, Nd5 is a d-light refractive index of the fifth lens, and Nd6 is a d-light refractive index of the sixth lens. When the relation is satisfied, the off-axis chromatic aberration is favorably corrected, so that the system resolution is improved, and the image plane is ensured to be clear.

An image capturing module includes a photosensitive element and the optical system of any of the above embodiments, wherein the photosensitive element is disposed on an image side of the optical system. Through adopting above-mentioned optical system, will be favorable to the miniaturized design of the module of making a video recording improves the installation flexibility of module, can improve the formation of image definition simultaneously, makes the module of making a video recording possess good formation of image quality.

An electronic device comprises a fixing piece and the camera module, wherein the camera module is arranged on the fixing piece. Through adopting above-mentioned module of making a video recording, will be favorable to electron device realizes miniaturized design, can also make simultaneously electron device possesses good quality of making a video recording.

An automobile comprises an automobile body and the electronic device, wherein the electronic device is arranged on the automobile body. By adopting the electronic device, the automobile can obtain clear imaging of environmental scenes, so that a driver or a driving system can judge the road condition and environment more timely and accurately, and the driving risk is reduced.

Drawings

Fig. 1 is a schematic structural diagram of an optical system according to a first embodiment of the present application;

FIG. 2 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the first embodiment;

fig. 3 is a schematic structural diagram of an optical system according to a second embodiment of the present application;

FIG. 4 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the second embodiment;

fig. 5 is a schematic structural diagram of an optical system according to a third embodiment of the present application;

FIG. 6 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical system in a third embodiment;

fig. 7 is a schematic structural diagram of an optical system according to a fourth embodiment of the present application;

FIG. 8 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical system in a fourth embodiment;

fig. 9 is a schematic structural diagram of an optical system according to a fifth embodiment of the present application;

FIG. 10 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical system in a fifth embodiment;

fig. 11 is a schematic structural diagram of an optical system according to a sixth embodiment of the present application;

FIG. 12 is a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of an optical system in a sixth embodiment;

fig. 13 is a schematic view of a camera module according to an embodiment of the present application;

fig. 14 is a schematic view of an electronic device according to an embodiment of the present application;

fig. 15 is a schematic view of an automobile according to an embodiment of the present application.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured 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. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

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

Referring to fig. 1, in some embodiments of the present application, the optical system 10 includes, in order from an object side to an image side, a first lens L1, a second lens L2, a third lens L3, a stop STO, a fourth lens L4, a fifth lens L5, and a sixth lens L6, where each of the first lens L1 to the sixth lens L6 includes only one lens. The first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative refractive power. Each lens of the optical system 10 is disposed coaxially with the stop STO, that is, the optical axis of each lens and the center of the stop STO are located on the same straight line, which may be referred to as the optical axis of the optical system 10. In some embodiments, the stop STO in the optical system 10 is a middle stop, and the middle stop can be disposed between the second lens L2 and the third lens L3, or between the fourth lens L4 and the fifth lens L5, in addition to being disposed between the third lens L3 and the fourth lens L4. The position of the stop can also be adjusted according to the actual situation, and in some embodiments, the stop STO can also be disposed on the object side of the optical system 10.

The first lens L1 includes an object side surface S1 and an image side surface S2, the second lens L2 includes an object side surface S3 and an image side surface S4, the third lens L3 includes an object side surface S5 and an image side surface S6, the fourth lens L4 includes an object side surface S7 and an image side surface S8, the fifth lens L5 includes an object side surface S9 and an image side surface S10, and the sixth lens includes an object side surface S11 and an image side surface S12. In addition, the optical system 10 further has a virtual image plane S13, and the image plane S13 is located on the image side of the sixth lens element L6. Generally, the image forming surface S13 of the optical system 10 coincides with the photosensitive surface of the photosensitive element, and for the sake of understanding, the image forming surface S13 may be regarded as the photosensitive surface of the photosensitive element.

In the above embodiment, the object-side surface S1 of the first lens element L1 is convex, and the image-side surface S2 is concave; the object-side surface S3 of the second lens element L2 is convex, and the image-side surface S4 is concave; the object-side surface S5 of the third lens element L3 is convex, and the image-side surface S6 is convex; the object-side surface S7 of the fourth lens element L4 is convex, and the image-side surface S8 is convex; the object-side surface S9 of the fifth lens element L5 is convex, and the image-side surface S10 is convex; the object-side surface S11 of the sixth lens element L6 is concave, and the image-side surface S12 is convex.

In addition, in the above-described embodiment, the image-side surface S10 of the fifth lens L5 is cemented with the object-side surface S11 of the sixth lens L6, so that the fifth lens L5 and the sixth lens L6 constitute a cemented lens. The fifth lens element L5 and the sixth lens element L6 provide positive refractive power to the optical system 10 as a whole, which is favorable for correcting aberration and can balance between downsizing and improving resolution.

In the above embodiments, the object-side surface and the image-side surface of the first lens L1, the second lens L2, the third lens L3, the fifth lens L5 and the sixth lens L6 are all spherical, and the object-side surface S7 and the image-side surface S8 of the fourth lens L4 may be aspheric. The spherical lens has simple manufacturing process and lower cost; the aspheric design can obtain more control variables for reducing the aberration, so that the aberration can be reduced without adding additional lenses, and further, the total length of the optical system 10 is effectively reduced, and the optical system 10 can have excellent optical effects on the premise of keeping the miniaturization design. The aberration problem can be effectively eliminated by the cooperation of the spherical lens and the aspherical lens, so that the optical system 10 has an excellent imaging effect, and the flexibility of lens design and assembly is improved, so that the system is balanced between high image quality and low cost. In some embodiments, each lens in optical system 10 is a spherical lens, i.e., the object-side and image-side surfaces of the lens are both spherical; in other embodiments, each lens in optical system 10 is an aspheric lens, i.e., the object-side and image-side surfaces of the lens are aspheric. Of course, in some embodiments, the object-side surface of any one of the first lens L1 through the sixth lens L6 may be spherical or aspherical, and the image-side surface of any one of the lenses may be spherical or aspherical. It is to be noted that the specific shapes of the spherical and aspherical surfaces in the embodiments are not limited to those shown in the drawings, which are mainly for exemplary reference and are not drawn strictly to scale.

The surface shape of the aspheric surface can be calculated by referring to an aspheric surface formula:

z is the distance from a corresponding point on the aspheric surface to a plane tangent to the surface vertex, r is the distance from the corresponding point on the aspheric surface to the optical axis, c is the curvature of the aspheric surface vertex, k is a conical coefficient, and Ai is a coefficient corresponding to the ith high-order term in the aspheric surface type formula.

In the above embodiment, the material of each lens in the optical system 10 is glass. In some embodiments, each lens in the optical system 10 is made of plastic. The glass lens can withstand higher temperatures and has excellent optical effects, while the plastic lens can reduce the weight of the optical system 10 and reduce manufacturing costs. In other embodiments, the first lens L1 is made of glass, and the second lens L2 to the sixth lens L6 are made of plastic, so that the lens located at the object side in the optical system 10 is made of glass, and therefore, the glass lenses located at the object side have a good tolerance effect on extreme environments, and are not susceptible to aging and the like caused by the influence of the object side environment, so that when the optical system 10 is in the extreme environments such as exposure to high temperature, the optical performance and cost of the system can be well balanced by the structure. Of course, the arrangement relationship of the lens materials in the optical system 10 is not limited to the above embodiment, and the material of any lens may be plastic or glass.

In some embodiments, the optical system 10 includes an ir-cut filter L7, and the ir-cut filter L7 is disposed on the image side of the sixth lens L6 and is fixed relative to each lens in the optical system 10. The infrared cut-off filter L7 is used for filtering infrared light and preventing the infrared light from reaching the imaging surface S13 of the system, thereby preventing the infrared light from interfering with normal imaging. An infrared cut filter L7 may be assembled with each lens as part of the optical system 10. In other embodiments, the ir-cut filter L7 is not part of the optical system 10, and the ir-cut filter L7 may be installed between the optical system 10 and the photosensitive element when the optical system 10 and the photosensitive element are assembled into a camera module. In some embodiments, an infrared cut filter L7 may also be disposed on the object side of the first lens L1. In addition, in some embodiments, the infrared cut filter L7 may not be provided, and an infrared filter is provided on any one of the first lens L1 to the sixth lens L6 to filter infrared light. By arranging the infrared cut-off filter or arranging the infrared filter film on the surface of the lens, the phenomenon of false color or ripple caused by the interference of infrared light in imaging can be avoided, and meanwhile, the effective resolution and the color reducibility can be improved.

In some embodiments, the first lens element L1 may also include two or more lens elements, wherein the object-side surface of the lens element closest to the object side is the object-side surface S1 of the first lens element L1, and the image-side surface of the lens element closest to the image side is the image-side surface S2 of the first lens element L1. Accordingly, any one of the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 in some embodiments is not limited to the case where only one lens is included.

In some embodiments, the optical system 10 also satisfies the following relationships:

-3 < f1/f < 0; where f1 is the effective focal length of the first lens L1, and f is the effective focal length of the optical system 10. Some embodiments of f1/f is-1.900, -1.880, -1.850, -1.830, -1.800, -1.790, -1.750, or-1.730. The first lens element L1 provides negative refractive power to the optical system 10, and when the above relationship is satisfied, the optical system 10 can have characteristics of wide viewing angle, low sensitivity and miniaturization.

-5 < f2/f < 0; where f2 is the effective focal length of the second lens L2, and f is the effective focal length of the optical system 10. Some embodiments of f2/f is-3.600, -3.550, -3.500, -3.400, -3.200, -3, -2.900, or-2.800. The second lens element L2 provides negative refractive power to the optical system 10, and when the above relationship is satisfied, the optical system 10 has a wide viewing angle, and meanwhile, the risk of generating ghost images is reduced, and the imaging quality is improved.

0 < (R3+ R4)/(R3-R4) < 3; wherein R3 is a radius of curvature of the object-side surface of the second lens L2 at the optical axis, and R4 is a radius of curvature of the image-side surface of the second lens L2 at the optical axis. In some embodiments (R3+ R4)/(R3-R4) is 0.950, 1, 1.100, 1.200, 1.500, 1.700, 1.800, or 1.850. When the above relationship is satisfied, the curvature radii of the object-side surface S3 and the image-side surface S4 of the second lens L2 can be reasonably configured, so that the degree of curvature of the second lens L2 can be effectively controlled, the processing difficulty of the second lens L2 is reduced, the problem of uneven coating due to excessive curvature of the second lens L2 is avoided, the risk of occurrence of ghost is reduced, and the resolving power of the optical system 10 is improved.

1 < CT3/CT2 < 5; wherein CT2 is the thickness of the second lens element L2 on the optical axis, and CT3 is the thickness of the third lens element L3 on the optical axis. CT3/CT2 in some embodiments is 2.000, 2.100, 2.400, 2.800, 3, 3.200, 3.500, 3.800, 4, or 4.100. When the above relationship is satisfied, the thicknesses of the second lens element L2 and the third lens element L3 can be configured reasonably, so that the refractive power at the front end of the system can be distributed reasonably, which is helpful for reducing the sensitivity of the system and correcting the aberration to improve the resolution of the system. The front end of the optical system 10 is composed of a first lens L1, a second lens L2, and a third lens L3.

F456/f < 3 > 0; where f456 is a combined focal length of the fourth lens L4, the fifth lens L5, and the sixth lens L6, and f is an effective focal length of the optical system 10. Some embodiments have f456/f of 1.670, 1.700, 1.720, 1.750, 1.780, 1.800, 1.820, or 1.840. When the above relationship is satisfied, it is ensured that the rear lens group of the system provides positive refractive power to the system, so as to converge the light rays diverging from the system end, and reduce the separation distance between the fourth lens element L4 and the fifth lens element L5, thereby facilitating the miniaturization design of the system, and at the same time, reducing the sensitivity of the system rear end, and suppressing the generation of high-order aberrations. The rear end of the optical system 10 is composed of a fourth lens L4, a fifth lens L5, and a sixth lens L6.

D16/CT4 is more than 0 and less than 3; the CT4 is the thickness of the fourth lens L4 on the optical axis, and d16 is the sum of the distances between the first lens L1 and the sixth lens L6 on the optical axis. In some embodiments d16/CT4 is 1.05, 1.10, 1.15, 1.20, 1.50, 1.80, 2.00, 2.20, or 2.25. When the above relationship is satisfied, the sum of the central thickness of the fourth lens L4 and the distance between adjacent lenses in the system can be effectively set, so that the total length of the optical system 10 can be effectively controlled, the miniaturization design of the system is ensured, the aberration of the system can be corrected, and the resolution of the system can be improved.

CT16/TTL is more than 0 and less than 1; the CT16 is the sum of the thicknesses of the first lens L1 to the sixth lens L6 on the optical axis, and TTL is the total optical length of the optical system 10. The CT16/TTL in some embodiments is 0.530, 0.540, 0.550, 0.560, or 0.570. When the above relationship is satisfied, the total length of the optical system 10 can be shortened, and the aberration of the system can be corrected, so as to improve the imaging quality.

The image-side surface of the fifth lens L5 is cemented with the object-side surface of the sixth lens L6, and the optical system 10 satisfies the relationship: -4 < R56/f56 < 0; wherein R56 is a curvature radius of a bonding surface of the fifth lens L5 and the sixth lens L6 at the optical axis, and f56 is a combined focal length of the fifth lens L5 and the sixth lens L6. Some embodiments R56/f56 is-3.25, -3.30, -3.40, -3.50, -3.55, -3.60, -3.65, or-3.70. When the relation is satisfied, the bending degree of the gluing surface can be reasonably controlled, so that the generation rate of ghost is reduced.

(1/2) FOV f/Imgh > 60; where FOV is the maximum angle of view of the optical system 10, f is the effective focal length of the optical system 10, and Imgh is the image height corresponding to the maximum angle of view of the optical system 10, i.e., the maximum diagonal angle of view of the system. The (1/2) FOV f/Imgh in some embodiments is 62.10, 62.50, 63.00, 63.20, 63.50, 63.70, or 63.80. When the above relation is satisfied, the resolution capability of the system is improved, and therefore the pixel quality is improved.

Nd3-Nd2 is more than 0; nd6-Nd5 is more than 0; wherein Nd2 is the refractive index of d light of the second lens L2, Nd3 is the refractive index of d light of the third lens L3, Nd5 is the refractive index of d light of the fifth lens L5, Nd6 is the refractive index of d light of the sixth lens L6, and the wavelength of d light is 587.56 nm. When the relation is satisfied, the off-axis chromatic aberration is favorably corrected, so that the system resolution is improved, and the image plane is ensured to be clear.

The optical system 10 of the present application is described in more detail with reference to the following examples:

first embodiment

Referring to fig. 1, in the first embodiment, the optical system 10 includes, in order from an object side to an image side, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 2 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the first embodiment. In addition, the reference wavelengths of the following embodiments (first to sixth embodiments) are all 587.56 nm.

The object-side surface S1 of the first lens element L1 is convex, and the image-side surface S2 is concave.

The object-side surface S3 of the second lens element L2 is convex, and the image-side surface S4 is concave.

The object-side surface S5 of the third lens element L3 is convex, and the image-side surface S6 is convex.

The object-side surface S7 of the fourth lens element L4 is convex, and the image-side surface S8 is convex.

The object-side surface S9 of the fifth lens element L5 is convex, and the image-side surface S10 is convex.

The object-side surface S11 of the sixth lens element L6 is concave, and the image-side surface S12 is convex.

The third lens element L3, the fourth lens element L4 and the fifth lens element L5 jointly provide positive refractive power for the optical system 10 to converge the incident light rays diverging from the first lens element L1 and the second lens element L2.

The object-side surface and the image-side surface of the first lens L1, the second lens L2, the third lens L3, the fifth lens L5, and the sixth lens L6 are all spherical, and the object-side surface S7 and the image-side surface S8 of the fourth lens L4 are aspheric. The aspheric design can obtain more control variables for reducing the aberration, so that the aberration can be reduced without adding additional lenses, the total length of the optical system 10 can be further effectively reduced, and the system can achieve excellent optical effects under the characteristics of small size and large viewing angle. In addition, the material of each lens in the optical system 10 is glass, and the glass lens can endure extreme temperature and has excellent and stable optical effect.

In the first to sixth embodiments, the image-side surface S10 of the fifth lens element L5 and the object-side surface S11 of the sixth lens element L6 are all cemented together to form a cemented lens, and at this time, the fifth lens element L5 and the sixth lens element L6 provide positive refractive power to the optical system 10 as a whole, which is beneficial to correcting aberrations and can balance between reducing the volume and improving the resolving power.

In the first embodiment, the optical system 10 satisfies the following relationships:

f 1/f-1.920; where f1 is the effective focal length of the first lens L1, and f is the effective focal length of the optical system 10. The first lens element L1 provides negative refractive power to the optical system 10, and when the above relationship is satisfied, the optical system 10 can have characteristics of wide viewing angle, low sensitivity and miniaturization.

f 2/f-2.739; where f2 is the effective focal length of the second lens L2, and f is the effective focal length of the optical system 10. The second lens element L2 provides negative refractive power to the optical system 10, and when the above relationship is satisfied, the optical system 10 has a wide viewing angle, and meanwhile, the risk of generating ghost images is reduced, and the imaging quality is improved.

(R3+ R4)/(R3-R4) ═ 1.149; wherein R3 is a radius of curvature of the object-side surface of the second lens L2 at the optical axis, and R4 is a radius of curvature of the image-side surface of the second lens L2 at the optical axis. When the above relationship is satisfied, the curvature radii of the object-side surface S3 and the image-side surface S4 of the second lens L2 can be reasonably configured, so that the degree of curvature of the second lens L2 can be effectively controlled, the processing difficulty of the second lens L2 is reduced, the problem of uneven coating due to excessive curvature of the second lens L2 is avoided, the risk of occurrence of ghost is reduced, and the resolving power of the optical system 10 is improved.

CT3/CT 2-4.118; wherein CT2 is the thickness of the second lens element L2 on the optical axis, and CT3 is the thickness of the third lens element L3 on the optical axis. When the above relationship is satisfied, the thicknesses of the second lens element L2 and the third lens element L3 can be configured reasonably, so that the refractive power at the front end of the system can be distributed reasonably, which is helpful for reducing the sensitivity of the system and correcting the aberration to improve the resolution of the system.

f456/f 1.855; where f456 is a combined focal length of the fourth lens L4, the fifth lens L5, and the sixth lens L6, and f is an effective focal length of the optical system 10. When the above relationship is satisfied, it is ensured that the rear lens group of the system provides positive refractive power to the system, so as to converge the light rays diverging from the system end, and reduce the separation distance between the fourth lens element L4 and the fifth lens element L5, thereby facilitating the miniaturization design of the system, and at the same time, reducing the sensitivity of the system rear end, and suppressing the generation of high-order aberrations.

d16/CT4 ═ 2.273; the CT4 is the thickness of the fourth lens L4 on the optical axis, and d16 is the sum of the distances between the first lens L1 and the sixth lens L6 on the optical axis. When the above relationship is satisfied, the sum of the central thickness of the fourth lens L4 and the distance between adjacent lenses in the system can be effectively set, so that the total length of the optical system 10 can be effectively controlled, the miniaturization design of the system is ensured, the aberration of the system can be corrected, and the resolution of the system can be improved.

CT16/TTL is 0.522; the CT16 is the sum of the thicknesses of the first lens L1 to the sixth lens L6 on the optical axis, and TTL is the total optical length of the optical system 10. When the above relationship is satisfied, the total length of the optical system 10 can be shortened, and the aberration of the system can be corrected, so as to improve the imaging quality.

The image-side surface of the fifth lens L5 is cemented with the object-side surface of the sixth lens L6, and the optical system 10 satisfies the following relationship:

r56/f56 ═ -3.225; wherein R56 is a curvature radius of a bonding surface of the fifth lens L5 and the sixth lens L6 at the optical axis, and f56 is a combined focal length of the fifth lens L5 and the sixth lens L6. When the relation is satisfied, the bending degree of the gluing surface can be reasonably controlled, so that the generation rate of ghost is reduced.

(1/2) FOV f/Imgh 62.050; where FOV is the maximum angle of view of the optical system 10, f is the effective focal length of the optical system 10, and Imgh is the image height corresponding to the maximum angle of view of the optical system 10. When the above relation is satisfied, the resolution capability of the system is improved, and therefore the pixel quality is improved.

Nd3-Nd2 ═ 0.423; nd6-Nd5 is 0.23; wherein Nd2 is the refractive index of d light of the second lens L2, Nd3 is the refractive index of d light of the third lens L3, Nd5 is the refractive index of d light of the fifth lens L5, Nd6 is the refractive index of d light of the sixth lens L6, and the wavelength of d light is 587.56 nm. When the relation is satisfied, the off-axis chromatic aberration is favorably corrected, so that the system resolution is improved, and the image plane is ensured to be clear.

In addition, each lens parameter of the optical system 10 is given by table 1 and table 2. Table 2 shows the aspherical surface coefficients of the lenses in table 1, where K is a conic coefficient and Ai is a coefficient corresponding to the i-th higher-order term in the aspherical surface formula. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in table 1, wherein the object on the object plane can form a sharp image on the image plane (image plane S13) of the optical system 10, and the image plane S13 can also be understood as the photosensitive surface of the photosensitive element during post-assembly. Surface numbers 1 and 2 respectively indicate an object-side surface S1 and an image-side surface S2 of the first lens L1, that is, a surface having a smaller surface number is an object-side surface and a surface having a larger surface number is an image-side surface in the same lens. The Y radius in table 1 is a curvature radius of the object-side surface or the image-side surface of the corresponding surface number on the optical axis. The first value of the lens in the "thickness" parameter set is the thickness of the lens on the optical axis, and the second value is the distance from the image-side surface of the lens to the object-side surface of the next optical element on the optical axis. The numerical value of the stop ST0 in the "thickness" parameter column is the distance on the optical axis from the stop ST0 to the vertex of the object-side surface of the subsequent lens (the vertex means the intersection point of the lens and the optical axis), and we default that the direction from the object side to the image side is the positive direction of the optical axis, when the value is negative, it means that the stop ST0 is disposed on the right side of the vertex of the object-side surface of the lens, and when the "thickness" parameter of the stop STO is positive, the stop ST0 is on the left side of the vertex of the object-side surface of the lens. The optical axes of the lenses in the embodiment of the present application are on the same straight line as the optical axis of the optical system 10.

In the first embodiment, the effective focal length f of the optical system 10 is 2.81mm, the f-number FNO of the system is 1.8, the maximum angle of view FOV in the diagonal direction is 146 °, and the total optical length TTL is 29.46 mm.

In addition, the relational expression calculation and the lens structure of each example are based on lens parameters (e.g., table 1, table 2, table 3, table 4, etc.).

TABLE 1

TABLE 2

Second embodiment

Referring to fig. 3, in the second embodiment, the optical system 10 includes, in order from the object side to the image side, the first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, a stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, and the sixth lens element L6 with negative refractive power. Fig. 4 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the second embodiment. Wherein the ordinate of the astigmatism diagram and the distortion diagram is the image height corresponding to the maximum field angle of the optical system 10, and the unit is mm.

In addition, the lens parameters of the optical system 10 in the second embodiment are given in table 3, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein.

TABLE 3

The optical system 10 in this embodiment satisfies the following relationship:

f1/f	-1.714	d16/CT4	1.104
				f2/f	-3.637	CT16/TTL	0.567
(R3+R4)/(R3-R4)	1.815	R56/f56	-3.528
				CT3/CT2	3.250	(1/2)FOV*f/Imgh	63.834
f456/f	1.698	Nd3-Nd2	0.423
						Nd6-Nd5	0.23

third embodiment

Referring to fig. 5, in the third embodiment, the optical system 10 includes, in order from the object side to the image side, the first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, a stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, and the sixth lens element L6 with negative refractive power. Fig. 6 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the third embodiment. Wherein the ordinate of the astigmatism diagram and the distortion diagram is the image height corresponding to the maximum field angle of the optical system 10, and the unit is mm.

In addition, the lens parameters of the optical system 10 in the third embodiment are given in table 4, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein.

TABLE 4

The optical system 10 in this embodiment satisfies the following relationship:

fourth embodiment

In the fourth embodiment, referring to fig. 7, the optical system 10 includes, in order from the object side to the image side, the first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, a stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, and the sixth lens element L6 with negative refractive power. Fig. 8 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the fourth embodiment. Wherein the ordinate of the astigmatism diagram and the distortion diagram is the image height corresponding to the maximum field angle of the optical system 10, and the unit is mm.

In addition, the lens parameters of the optical system 10 in the fourth embodiment are given in table 5, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein.

TABLE 5

The optical system 10 in this embodiment satisfies the following relationship:

f1/f	-1.726	d16/CT4	1.028
				f2/f	-3.596	CT16/TTL	0.579
(R3+R4)/(R3-R4)	1.867	R56/f56	-3.7
				CT3/CT2	2.000	(1/2)FOV*f/Imgh	63.834
f456/f	1.661	Nd3-Nd2	0.423
						Nd6-Nd5	0.23

fifth embodiment

Referring to fig. 9, in the fifth embodiment, the optical system 10 includes, in order from the object side to the image side, the first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, a stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, and the sixth lens element L6 with negative refractive power. Fig. 10 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the fifth embodiment. Wherein the ordinate of the astigmatism diagram and the distortion diagram is the image height corresponding to the maximum field angle of the optical system 10, and the unit is mm.

In addition, the lens parameters of the optical system 10 in the fifth embodiment are given in table 6, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein.

TABLE 6

The optical system 10 in this embodiment satisfies the following relationship:

f1/f	-1.746	d16/CT4	1.105
				f2/f	-3.540	CT16/TTL	0.567
(R3+R4)/(R3-R4)	1.819	R56/f56	-3.626
				CT3/CT2	2.400	(1/2)FOV*f/Imgh	63.834
f456/f	1.679	Nd3-Nd2	0.423
						Nd6-Nd5	0.23

sixth embodiment

Referring to fig. 11, in the sixth embodiment, the optical system 10 includes, in order from the object side to the image side, the first lens element L1 with negative refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with positive refractive power, a stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, and the sixth lens element L6 with negative refractive power. Fig. 12 includes a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the optical system 10 in the sixth embodiment. Wherein the ordinate of the astigmatism diagram and the distortion diagram is the image height corresponding to the maximum field angle of the optical system 10, and the unit is mm.

In addition, the lens parameters of the optical system 10 in the sixth embodiment are given in table 7, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein.

TABLE 7

The optical system 10 in this embodiment satisfies the following relationship:

f1/f	-1.733	d16/CT4	1.105
				f2/f	-3.678	CT16/TTL	0.567
(R3+R4)/(R3-R4)	1.890	R56/f56	-3.637
				CT3/CT2	2.4	(1/2)FOV*f/Imgh	63.834
f456/f	1.690	Nd3-Nd2	0.423
						Nd6-Nd5	0.23

referring to fig. 13, in an embodiment provided in the present application, the optical system 10 and the photosensitive element 210 are assembled to form the image capturing module 20, and the photosensitive element 210 is disposed on the image side of the sixth lens element L6, i.e., on the image side of the optical system 10. Generally, the photosensitive surface of the photosensitive element 210 overlaps with the image forming surface S13 of the optical system 10. The photosensitive element 210 may be a CCD (charge coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). Through adopting above-mentioned optical system 10, will be favorable to making a video recording the miniaturized design of module 20, can improve the formation of image definition of module simultaneously, make the module 20 of making a video recording possess good formation of image quality.

Referring to the above embodiments and the drawings (fig. 1 and 3), in some embodiments, an infrared cut filter L7 and a protective glass L8 are further disposed between the sixth lens L6 and the imaging surface S13 of the system. The infrared cut filter L7 is used to filter infrared light, and the protective glass L8 is used to protect the photosensitive element 210. The infrared cut filter L7 and the protective glass L8 may be part of the optical system 10, or may be mounted between the optical system 10 and the light-receiving element 210 together when the optical system 10 and the light-receiving element 210 are assembled.

In some embodiments, the distance between the photosensitive element 210 and each lens in the optical system 10 is relatively fixed, and the camera module 20 is a fixed focus module. In other embodiments, a driving mechanism such as a voice coil motor may be provided to enable the photosensitive element 210 to move relative to each lens in the optical system 10, so as to achieve a focusing effect. Specifically, a coil electrically connected to the driving chip is disposed on the lens barrel to which the above lenses are assembled, and the image pickup module 20 is further provided with a magnet, so that the lens barrel is driven to move relative to the photosensitive element 210 by a magnetic force between the energized coil and the magnet, thereby achieving a focusing effect. In other embodiments, a similar driving mechanism may be provided to drive a portion of the lenses in the optical system 10 to move, thereby achieving an optical zoom effect.

Referring to fig. 14, some embodiments of the present disclosure further provide an electronic device 30, and the camera module 20 is applied to the electronic device 30 to enable the electronic device 30 to have a camera function. Specifically, the electronic device 30 includes a fixing member 310, the camera module 20 is mounted on the fixing member 310, and the fixing member 310 may be a circuit board, a middle frame, a housing, or the like. The electronic device 30 may be, but is not limited to, a smart phone, a smart watch, an e-book reader, a vehicle-mounted camera (e.g., a car recorder), a monitoring device, a medical device (e.g., an endoscope), a tablet computer, a biometric device (e.g., a fingerprint recognition device or a pupil recognition device), a PDA (personal digital Assistant), an unmanned aerial vehicle, and the like. Specifically, in some embodiments, the electronic device 30 is a smart phone, the smart phone includes a middle frame and a circuit board, the circuit board is disposed in the middle frame, the camera module 20 is installed in the middle frame of the smart phone, and the light sensing element 210 is electrically connected to the circuit board. The camera module 20 can be used as a front camera module or a rear camera module of the smart phone. By adopting the camera module 20 provided by the embodiment of the present application, the electronic device 30 can be miniaturized, and the electronic device 30 can have excellent camera quality.

Referring to fig. 15, some embodiments of the present application also provide an automobile 40. At this time, when the electronic device 30 is an in-vehicle image pickup apparatus, the electronic device 30 may function as a front-view image pickup device, a rear-view image pickup device, or a side-view image pickup device of the automobile 40. Specifically, the automobile 40 includes a vehicle body 410, and the electronic device 30 is mounted on the vehicle body 410. The electronic device 30 may be mounted on any position of the front side (e.g., at the air intake grille) of the vehicle body 410, such as a left headlamp, a right headlamp, a left rearview mirror, a right rearview mirror, a trunk lid, and a roof. Secondly, a display device may be disposed in the automobile 40, and the electronic device 30 is in communication connection with the display device, so that the image obtained by the electronic device 30 on the automobile body 410 can be displayed on the display device in real time, and a driver can obtain environment information around the automobile body 410 in a wider range, thereby making the driver more convenient and safer to drive and park. When a plurality of electronic devices 30 are provided to acquire scenes in different orientations, image information obtained by the electronic devices 30 can be synthesized and can be presented on the display apparatus in the form of a top view.

Specifically, in some embodiments, the automobile 40 includes at least four electronic devices 30, and the electronic devices 30 are respectively installed at the front side (e.g., at the air intake grille), the left side (e.g., at the left rear view mirror), the right side (e.g., at the right rear view mirror), and the rear side (e.g., at the trunk lid) of the automobile body 410 to construct an automobile all-around system. The automobile all-round system comprises four (or more) electronic devices 30 which are arranged at the front, the back, the left and the right of an automobile body 410, wherein the plurality of electronic devices 30 can simultaneously collect scenes around an automobile 40, then image information collected by the electronic devices 30 is subjected to steps of distortion reduction, visual angle conversion, image splicing, image enhancement and the like through an image processing unit, and finally a seamless 360-degree panoramic top view around the automobile 40 is formed and displayed on a display device. Of course, instead of displaying a panoramic view, a single-sided view of any orientation may be displayed. In addition, a scale line corresponding to the display image can be configured on the display device so as to facilitate the driver to accurately determine the direction and distance of the obstacle.

By adopting the electronic device 30, the automobile 40 can obtain clear images of environmental scenes, so that a driver or a driving system can judge road conditions and environments (such as finding obstacles) more timely and accurately, and driving risks are reduced. On the other hand, the miniaturized design of the electronic device 30 also advantageously improves the flexibility of installation, so that the electronic device 30 can be installed in more areas of the vehicle body 410, thereby increasing the imaging range to cover the blind spot.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. An optical system comprising, in order from an object side to an image side:

a third lens element with positive refractive power;

a fourth lens element with positive refractive power;

a fifth lens element with positive refractive power;

0＜f456/f＜3；

wherein f456 is a combined focal length of the fourth lens, the fifth lens and the sixth lens, and f is an effective focal length of the optical system.

2. The optical system according to claim 1, characterized in that the following relation is satisfied:

-3＜f1/f＜0；

wherein f1 is the effective focal length of the first lens.

3. The optical system according to claim 1, characterized in that the following relation is satisfied:

-5＜f2/f＜0；

wherein f2 is the effective focal length of the second lens.

4. The optical system according to claim 1, characterized in that the following relation is satisfied:

0＜(R3+R4)/(R3-R4)＜3；

wherein R3 is a curvature radius of an object side surface of the second lens at an optical axis, and R4 is a curvature radius of an image side surface of the second lens at the optical axis.

5. The optical system according to claim 1, characterized in that the following relation is satisfied:

1＜CT3/CT2＜5；

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

6. The optical system according to claim 1, characterized in that the following relation is satisfied:

0＜d16/CT4＜3；

wherein CT4 is the thickness of the fourth lens element on the optical axis, and d16 is the sum of the distances between the adjacent first to sixth lens elements on the optical axis.

7. The optical system according to claim 1, characterized in that the following relation is satisfied:

0＜CT16/TTL＜1；

wherein CT16 is a sum of thicknesses of the first lens element to the sixth lens element on an optical axis, and TTL is a total optical length of the optical system.

8. The optical system of claim 1, wherein an image-side surface of the fifth lens is cemented to an object-side surface of the sixth lens, and the optical system satisfies the following relationship:

-4＜R56/f56＜0；

wherein R56 is a curvature radius of a bonding surface of the fifth lens element and the sixth lens element at an optical axis, and f56 is a combined focal length of the fifth lens element and the sixth lens element.

9. The optical system according to claim 1, characterized in that the following relation is satisfied:

(1/2)FOV*f/Imgh＞60；

wherein FOV is a maximum angle of view of the optical system, and Imgh is an image height corresponding to the maximum angle of view of the optical system.

10. The optical system according to claim 1, characterized in that the following relation is satisfied:

Nd3-Nd2＞0；Nd6-Nd5＞0；

wherein Nd2 is a d-light refractive index of the second lens, Nd3 is a d-light refractive index of the third lens, Nd5 is a d-light refractive index of the fifth lens, and Nd6 is a d-light refractive index of the sixth lens.

11. An image pickup module comprising a photosensitive element and the optical system according to any one of claims 1 to 10, wherein the photosensitive element is disposed on an image side of the optical system.

12. An electronic device, comprising a fixing member and the camera module of claim 11, wherein the camera module is disposed on the fixing member.

13. An automobile comprising a vehicle body and the electronic device according to claim 12, wherein the electronic device is provided in the vehicle body.