CN214375523U

CN214375523U - Optical system, camera module, electronic equipment and automobile

Info

Publication number: CN214375523U
Application number: CN202120608834.6U
Authority: CN
Inventors: 乐宇明; 蔡雄宇; 周宝; 赵迪
Original assignee: Tianjin OFilm Opto Electronics Co Ltd
Current assignee: Jiangxi Oufei Optics Co ltd
Priority date: 2021-03-25
Filing date: 2021-03-25
Publication date: 2021-10-08
Anticipated expiration: 2031-03-25

Abstract

The utility model relates to an optical system, module, electronic equipment 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; 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 having a convex object-side surface at paraxial region; a fourth lens element with positive refractive power having a convex object-side surface and a convex image-side surface at paraxial region; a fifth lens element with positive refractive power having a convex object-side surface and a convex image-side surface at a paraxial region; a sixth lens element with negative refractive power; the optical system also satisfies the relationship: -9.1 < f1/CT1 < -7; f1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens at the optical axis. The aberration of the optical system can be well corrected, particularly the astigmatic aberration can be effectively suppressed, thereby being beneficial to having good imaging quality.

Description

Optical system, camera module, electronic equipment and automobile

Technical Field

The utility model relates to a photographic imaging technology field especially relates to an optical system, module, electronic equipment and car of making a video recording.

Background

With the development of vehicle-mounted devices, the application of vehicle-mounted auxiliary systems such as ADAS (advanced driving assistance system), DMS (driver monitoring system), CMS (collision warning system) and the like in automobiles is gradually promoted. Generally, the vehicle-mounted auxiliary system not only requires monitoring the state of the driver, for example, the mental state is presumed according to the eye state, the eye closing times, the eye closing amplitude, yawning and other related information, but also monitors and identifies according to the road condition outside the driving cabin, so that the safety early warning can be provided more comprehensively, and the prevention can be made in advance.

However, these vehicle-mounted auxiliary systems generally need to acquire the state and road condition information of the driver through the camera device, that is, the imaging quality of the camera device undoubtedly affects the recognition accuracy of the vehicle-mounted auxiliary systems on the image. Therefore, it has become one of the important points in the industry to improve the recognition accuracy of the system by improving the imaging quality of the image pickup apparatus, and thus to improve the driving safety.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is necessary to provide an optical system, a camera module, an electronic device, and an automobile, which are directed to improving the imaging quality.

An optical system includes, in order from an object side to an image side along an optical axis:

a first lens element with negative refractive power;

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

a third lens element with positive refractive power having a convex object-side surface at paraxial region;

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

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

a sixth lens element with negative refractive power;

the optical system further satisfies the relationship:

-9.1＜f1/CT1＜-7；

f1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens at the optical axis.

The optical system with the lens refractive power and the surface design can realize good correction of aberration while having large visual angle characteristics, thereby being beneficial to the optical system to have good imaging quality. The first lens and the second lens are both negative lenses, so that a reverse-focus lens structure can be formed, light rays with a large-angle included angle with an optical axis of the optical system can be effectively deflected by the first lens and the second lens to enter the optical system, and the optical system has the characteristic of a large visual angle and even a wide angle. In addition, by matching with the positive refractive power design of the third lens element, the fourth lens element and the fifth lens element, the negative refractive power contribution provided by the first lens element and the second lens element can be effectively balanced, so that the distortion caused by a large viewing angle can be effectively corrected, and the imaging quality can be improved. Furthermore, since the object-side surface and the image-side surface of the fourth lens element and the fifth lens element are convex, the axial size of the optical system can be reduced, which is beneficial for miniaturization. The sixth lens is designed as a negative lens, so that the larger positive refractive power provided by the third lens to the fifth lens can be further balanced, the aberration of the optical system can be further corrected, and the back focus of the optical system can be increased. When the relation condition is met, on one hand, the center thickness of the first lens can be prevented from being too small, so that the tolerance sensitivity of the center thickness of the first lens is reduced, the processing difficulty of the first lens is reduced, the assembly yield of the lens is improved, and the production cost is further reduced; on the other hand, the strength of the negative refractive power of the first lens element can be controlled within a reasonable range, so that astigmatism which is difficult to correct and is caused by overlarge strength of the negative refractive power of the first lens element can be avoided, and the optical system has good imaging quality; meanwhile, the optical system has wide-angle characteristics, and the situation that the angle of view is too small due to insufficient refractive power strength of the first lens is avoided.

In one embodiment, the optical system satisfies the relationship:

0＜D/(2*Imgh*FOV)≤0.04deg^-1；

d is a maximum effective clear aperture of the object-side surface of the first lens element, Imgh is half an image height corresponding to a maximum field angle of the optical system, and FOV is the maximum field angle of the optical system. When the relational expression condition is satisfied, the object side end of the optical system can have the characteristic of a small aperture, and thus, the small head design can be realized.

In one embodiment, the optical system satisfies the relationship:

3＜Imgh/EPD＜4；

imgh is half the image height corresponding to the maximum field angle of the optical system, and EPD is the entrance pupil diameter of the optical system. When the relational expression condition is satisfied, the image surface brightness of the optical system is favorably improved. When the difference exceeds the upper limit of the relational expression, the diameter of the entrance pupil of the optical system is too small, namely the width of a light beam entering the optical system is reduced, so that the improvement of the image surface brightness is not facilitated, and the poor imaging definition is further caused; if the value is lower than the lower limit of the relational expression, the size of the imaging surface of the optical system is too small, and the field range of the optical system is narrowed, which is not favorable for increasing the field angle of the optical system.

In one embodiment, the optical system satisfies the relationship:

6＜f3/f＜13；

f3 is the effective focal length of the third lens, and f is the effective focal length of the optical system. Since the incident light first passes through the first lens element and the second lens element with strong negative refractive power, it is easy to cause large field curvature when the marginal light reaches the imaging surface. By arranging the third lens element with positive refractive power, and when the relational expression condition is satisfied, the refractive power strength of the third lens element can be reasonably configured, which is beneficial to balancing aberration caused by stronger negative refractive power of the first lens element and the second lens element, namely, the edge aberration of the optical system can be corrected, and the imaging resolution can be improved. When the optical power exceeds the upper limit of the relational expression, the positive refractive power of the third lens element is insufficient, and the peripheral aberration of the optical system is difficult to correct; if the value is lower than the lower limit of the relational expression, the positive refractive power of the third lens element is too high, and the over-correction is likely to occur, thereby reducing the imaging quality.

In one embodiment, the optical system satisfies the relationship:

0.6＜(D12+CT2)/(CT3+D34)＜1.6；

d12 is a distance on an optical axis from an image-side surface of the first lens element to an object-side surface of the second lens element, CT2 is a thickness of the second lens element on the optical axis, CT3 is a thickness of the third lens element on the optical axis, and D34 is a distance on the optical axis from the image-side surface of the third lens element to an object-side surface of the fourth lens element. When the relational expression condition is met, the thicknesses of the second lens and the third lens and the distance between the second lens and the third lens and the adjacent lens can be mutually constrained, the size of an object end structure of the optical system can be reasonably controlled, the structural compactness of the optical system can be improved, and the miniaturized design is met; on the other hand, the incident light can have reasonable transition space when passing through the front four lenses of the optical system, so that the aberration of the system can be corrected, and the imaging resolution can be improved. When the range of the relation is exceeded, the configuration between the thicknesses of the corresponding lenses and the distances among the lenses in the front four lenses is unreasonable, on one hand, the aberration of the optical system is not corrected, and therefore the imaging quality is reduced; on the other hand, the thickness of the corresponding lens and the distance between the lenses are too large, which increases the burden of shortening the total length of the optical system, and is not favorable for the miniaturization design of the optical system.

In one embodiment, the fifth lens is cemented with the sixth lens, and the optical system satisfies the relationship:

4.2＜f56/f＜12.5；

f56 is the combined focal length of the fifth lens and the sixth lens, and f is the effective focal length of the optical system. The fifth lens element provides positive refractive power for the system, and the sixth lens element provides negative refractive power for the system, which are useful for correcting aberrations between the two lens elements by gluing the two elements together. Meanwhile, the method is also beneficial to correcting the problems of edge aberration, chromatic aberration, astigmatism and the like of the optical system when the relational expression condition is met. When the refractive power of the cemented lens formed by the fifth lens element and the sixth lens element is too small, the generation of large edge aberration and chromatic aberration is difficult to be suppressed, which is not favorable for improving the resolution performance; when the refractive power is lower than the lower limit of the relational expression, the total refractive power of the cemented lens formed by the fifth lens element and the sixth lens element is too strong, so that the optical system is prone to generate a severe astigmatism phenomenon, which is not favorable for improving the imaging quality.

In one embodiment, the optical system includes an aperture stop disposed between the third lens and the fourth lens, and the optical system satisfies a relationship:

-2.4＜f123/f＜-1.4；

f123 is a combined focal length of the first lens, the second lens and the third lens, and f is an effective focal length of the optical system. When the relational condition is met, the whole front lens group positioned at the object space of the aperture diaphragm provides negative refractive power for the optical system, so that light rays incident at a large angle can pass through the aperture diaphragm, the wide-angle design of the optical system is realized, and the image surface brightness of the optical system with a large-angle view field is improved. When the maximum refractive power of the front lens group exceeds the upper limit of the relation, the negative refractive power of the front lens group is too strong, and the fringe field of the optical system with the large visual angle characteristic is easy to generate serious astigmatism, so that the imaging resolution of the fringe field is reduced.

In one embodiment, the optical system satisfies the relationship:

3.5＜R3/CT2＜16.5；

r3 is the radius of curvature of the object-side surface of the second lens at the optical axis, and CT2 is the thickness of the second lens at the optical axis. The object side of the second lens is convex at the paraxial region, the image side is concave at the paraxial region, and the whole structure of the second lens is meniscus-shaped, so that light can be further converged, and the contraction of incident light is facilitated. Meanwhile, the thickness and the surface type of the second lens are reasonably configured by satisfying the above relational expression conditions, so that the problem that the processing difficulty is too large due to too much bending of the object side surface of the second lens can be avoided, and the light-weight design of an optical system is facilitated.

In one embodiment, the optical system satisfies the relationship:

7.8＜TTL/f＜9.5；

TTL is a distance on an optical axis from an object-side surface of the first lens element to an imaging surface of the optical system, and f is an effective focal length of the optical system. By satisfying the relationship between the total optical length and the effective focal length of the optical system, the requirement of the optical system on a large field angle is satisfied, and the total optical length of the optical system can be effectively restricted, so that the miniaturization design of the optical system is satisfied. When the upper limit of the relational expression is exceeded, the total length of the optical system is too long, which is not beneficial to miniaturization; if the focal length of the optical system is too long below the lower limit of the relational expression, it is not favorable to satisfy the requirement of the optical system for the large viewing angle characteristic, and it is difficult to obtain sufficient object space information.

In one embodiment, the optical system satisfies the relationship:

10mm＜2*f*tan(FOV/2)＜11.5mm；

f is the effective focal length of the optical system, and the FOV is the maximum field angle of the optical system. When the relational expression condition is satisfied, the distortion quantity of the whole optical system can be controlled, so that the distortion of the optical system can be well inhibited, the resolution capability of the optical system is improved, and the distortion risk of a shot picture with a large visual field range is reduced.

A camera module comprises an image sensor and the optical system, wherein the image sensor is arranged on the image side of the optical system. The aberration, especially astigmatism, of the optical system can be well corrected, so that the camera module can have good shooting quality.

The utility model provides an electronic equipment, electronic equipment includes mounting and foretell camera module, camera module locates the mounting. Through adopting above-mentioned module of making a video recording, electronic equipment can possess good shooting quality.

The utility model provides an automobile, the automobile includes installation department and foretell electronic equipment, electronic equipment set up in the installation department. Through adopting above-mentioned electronic equipment who has optical system of using, the car can acquire more clear driver's state and road conditions state through electronic equipment to can improve the recognition accuracy of on-vehicle auxiliary system to the image, can make more accurate safety precaution with this, and then be favorable to improving driving safety.

Drawings

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

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

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

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

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

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

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

FIG. 12 includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the 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 structural diagram of an electronic device according to an embodiment of the present application;

fig. 15 is a schematic structural diagram of an automobile to which an electronic device is applied according to an embodiment of the present application.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "thickness," "upper," "front," "rear," "axial," "radial," and the like are used in the orientation or positional relationship shown in the drawings for convenience in describing the present invention and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

It will be understood that when an element is referred to as being "secured to" or "disposed on" 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.

Referring to fig. 1, an embodiment of the present application provides an optical system 10 having a six-piece structure, and the optical system 10 may be applied to an in-vehicle image pickup apparatus to acquire a face state or a road condition of a driver.

The optical system includes, in order from the object side to the image side along the optical axis 101, 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.

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

Further, in the embodiment of the present application, the object-side surface S3 of the second lens element L2 is convex at the paraxial region, and the image-side surface S4 is concave at the paraxial region; the object-side surface S5 of the third lens element L3 is convex at paraxial region; the object-side surface S7 of the fourth lens element L4 is convex at the paraxial region, and the image-side surface S8 is convex at the paraxial region; the object-side surface S9 of the fifth lens element L5 is convex at the paraxial region, and the image-side surface S10 is convex at the paraxial region.

The optical system 10 with the above-mentioned lens refractive power and surface design can achieve good aberration correction while having a large viewing angle characteristic, thereby being beneficial to the optical system 10 to have good imaging quality. The first lens L1 and the second lens L2 are both negative lenses, so that a retrofocus lens structure can be formed, and incident light rays having a large angle with the optical axis 101 of the optical system 10 can be effectively deflected by the first lens L1 and the second lens L2 to enter the optical system 10, so that the optical system 10 has a large angle of view and even a wide angle. In addition, by matching with the positive refractive power design of the third lens element L3, the fourth lens element L4 and the fifth lens element L5, the negative refractive power contribution provided by the first lens element L1 and the second lens element L2 can be effectively balanced, so as to effectively correct the distortion caused by a large viewing angle, thereby improving the imaging quality. Further, since the object-side and image-side surfaces of the fourth lens element L4 and the fifth lens element L5 are convex, the axial dimension of the optical system 10 can be reduced, which is advantageous for compact design. The sixth lens element L6 is designed as a negative lens element, which can further balance the larger positive refractive power provided by the third lens element L3 to the fifth lens element L5, so as to further correct the aberration of the optical system 10, and simultaneously facilitate increasing the back focus of the optical system 10, so as to increase the focusing range to reduce the tolerance sensitivity when assembling with the image sensor, and facilitate increasing the propagation space after the light exits from the sixth lens element L6, thereby reducing the difficulty in designing the optical system 10 when adjusting the aberration.

In addition, the optical system 10 in the embodiment of the present application also satisfies the following relationship:

-9.1 < f1/CT1 < -7; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 at the optical axis. When the above-mentioned lens refractive power and surface design are satisfied and the above-mentioned relation conditions are satisfied, on one hand, the center thickness of the first lens element L1 is prevented from being too small, so as to reduce the tolerance sensitivity of the center thickness of the first lens element L1, thereby reducing the difficulty of the processing technology of the first lens element L1, and further being beneficial to improving the assembly yield of the lens and further reducing the production cost; on the other hand, the negative refractive power of the first lens element L1 can be controlled within a reasonable range, so that astigmatism that is hard to correct is prevented from being generated in the optical system 10 due to the fact that the refractive power of the first lens element L1 is too large, and the optical system 10 has good imaging quality; meanwhile, the optical system 10 is advantageous to have a wide-angle characteristic, and the problem of an excessively small angle of view caused by insufficient refractive power of the first lens element L1 is avoided. In some embodiments, the relationship that optical system 10 satisfies may be specifically-9.03, -8.96, -8.77, -8.54, -8.3, -8.15, -7.92, -7.64, -7.52, -7.43, -7.33, -7.28, or-7.15.

Further, in some embodiments, the optical system 10 also satisfies at least one of the following relationships, and may have a corresponding technical effect when either relationship is satisfied:

0＜D/(2*Imgh*FOV)≤0.04deg^-1(ii) a D is the maximum effective light-passing aperture of the object-side surface S1 of the first lens L1, Imgh is half the image height corresponding to the maximum angle of view of the optical system 10, and FOV is the maximum angle of view of the optical system 10. When this relational condition is satisfied, the object side end of the optical system 10 can be made to have a small aperture characteristic, and thus a small head design can be realized. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.0108, 0.011, or 0.0112, with a numerical unit deg^-1. It should be noted that Imgh can also be interpreted as the radius of the largest imaging circle. In addition, the optical system 10 is generally assembled with an image sensor having a rectangular effective pixel area with a diagonal direction to form a camera module, and when the image sensor is assembled,imgh is also understood to mean half the length of the diagonal of the rectangular effective pixel area.

3 < Imgh/EPD < 4; imgh is half the image height corresponding to the maximum field angle of the optical system 10, and EPD is the entrance pupil diameter of the optical system 10. When the condition of the relational expression is satisfied, the image plane brightness of the optical system 10 is favorably improved. When the upper limit of the relational expression is exceeded, the diameter of the entrance pupil of the optical system 10 is too small, that is, the width of the light beam entering the optical system 10 is reduced, which is not beneficial to improving the brightness of the image plane, and further leads to poor imaging definition; if the value is lower than the lower limit of the relational expression, the size of the image plane of the optical system 10 is too small, and the field range of the optical system 10 is narrowed, which is disadvantageous for increasing the field angle of the optical system 10. In some embodiments, the relationship satisfied by optical system 10 may be specifically 3.3, 3.32, 3.37, 3.46, 3.49, 3.57, 3.61, 3.66, or 3.7.

F3/f is more than 6 and less than 13; f3 is the effective focal length of the third lens L3, and f is the effective focal length of the optical system 10. Since the incident light ray first passes through the first lens element L1 and the second lens element L2 with strong negative refractive power, it is easy to cause the edge light ray to have large curvature of field when reaching the image plane S13. By providing the third lens element L3 with positive refractive power, and when the relationship is satisfied, the refractive power of the third lens element L3 can be configured reasonably, which is beneficial to balance the aberration caused by the stronger negative refractive power of the first lens element L1 and the second lens element L2, i.e., the peripheral aberration of the optical system 10 can be corrected, and the imaging resolution can be improved. If the upper limit of the relational expression is exceeded, the positive refractive power of the third lens element L3 is insufficient, and it is difficult to correct the peripheral aberration of the optical system 10; if the value is lower than the lower limit of the relational expression, the positive refractive power of the third lens element L3 is too high, and the overcorrection is liable to occur, thereby degrading the image quality. In some embodiments, the relationship satisfied by optical system 10 may be specifically 6.3, 6.41, 6.83, 7.2, 7.26, 8.36, 8.9, 9.3, 10.3, 10.64, 11.5, 11.97, 12.2, 12.56, or 12.88.

0.6 < (D12+ CT2)/(CT3+ D34) < 1.6; d12 is the distance on the optical axis from the image-side surface S2 of the first lens element L1 to the object-side surface S3 of the second lens element L2, CT2 is the thickness of the second lens element L2 on the optical axis, CT3 is the thickness of the third lens element L3 on the optical axis, and D34 is the distance on the optical axis from the image-side surface S6 of the third lens element L3 to the object-side surface S7 of the fourth lens element L4. When the condition of the relational expression is satisfied, the thicknesses of the second lens L2 and the third lens L3 and the distance between the second lens L2 and the third lens L3 and the adjacent lens can be mutually constrained, the size of the object end structure of the optical system 10 can be reasonably controlled, on one hand, the structural compactness of the optical system 10 is favorably improved, and the requirement on miniaturization design is satisfied; on the other hand, the incident light can have a reasonable transition space when passing through the front four lenses of the optical system 10, thereby being beneficial to correcting system aberration and improving imaging resolution. When the range of the relation is exceeded, the arrangement between the thicknesses of the corresponding lenses and the distances between the lenses in the front four lenses is unreasonable, which is unfavorable for correcting the aberration of the optical system 10, thereby reducing the imaging quality; on the other hand, the thickness of the corresponding lens and the distance between the lenses are too large, which increases the burden of shortening the total length of the optical system 10, and is not favorable for the miniaturization design of the optical system 10. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.8, 0.84, 0.96, 1.19, 1.27, 1.38, 1.42, 1.47, or 1.5.

F56/f is more than 4.2 and less than 12.5; f56 is the combined focal length of the fifth lens L5 and the sixth lens L6, f is the effective focal length of the optical system 10, and wherein the fifth lens L5 is cemented with the sixth lens L6. The fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative refractive power can correct the aberrations of the two lens elements by gluing them together. Meanwhile, the requirements of the relational expression are satisfied, which is also beneficial to correcting the problems of the edge aberration, chromatic aberration, astigmatism and the like of the optical system 10. If the refractive power exceeds the upper limit of the relational expression, the refractive power of the cemented lens composed of the fifth lens element L5 and the sixth lens element L6 is too small to suppress the occurrence of large peripheral aberration and chromatic aberration, which is not favorable for improving the resolution performance; if the refractive power is lower than the lower limit of the relational expression, the total refractive power of the cemented lens formed by the fifth lens element L5 and the sixth lens element L6 is too strong, so that the optical system 10 is prone to generate a severe astigmatism phenomenon, which is not favorable for improving the imaging quality. In some embodiments, the relationship satisfied by optical system 10 may be specifically 4.3, 4.5, 4.8, 5.3, 6.7, 8.4, 9.61, 10.8, 11.2, 11.6, or 12.1.

-2.4 < f123/f < -1.4; f123 is a combined focal length of the first lens L1, the second lens L2, and the third lens L3, and f is an effective focal length of the optical system 10, wherein the optical system 10 includes an aperture stop disposed between the third lens L3 and the fourth lens L4. When the relational condition is satisfied, the front lens group located at the object space of the aperture diaphragm integrally provides negative refractive power for the optical system 10, so that the light rays incident at a large angle can pass through the aperture diaphragm, the wide-angle design of the optical system 10 is realized, and the image surface brightness of the optical system 10 with a large-angle view field is improved. When the upper limit of the relation is exceeded, the negative refractive power of the front lens group is too strong, and the fringe field of the optical system 10 with a large viewing angle characteristic is prone to generate relatively serious astigmatism, thereby reducing the imaging resolution of the fringe field. In some embodiments, the relationship that optical system 10 satisfies may be specifically-2.3, -2.2, -2, -1.8, -1.7, -1.6, or-1.5.

R3/CT2 is more than 3.5 and less than 16.5; r3 is the radius of curvature of the object-side surface S3 of the second lens L2 at the optical axis, and CT2 is the thickness of the second lens L2 at the optical axis. The object-side surface S3 of the second lens element L2 is convex at a paraxial region, the image-side surface S4 is concave at a paraxial region, and the entire structure of the second lens element L2 is meniscus-shaped, so that light can be further converged, and contraction of incident light is facilitated. Meanwhile, by satisfying the above-mentioned relation conditions to reasonably arrange the thickness and the surface shape of the second lens L2, the thickness of the second lens L2 can be prevented from being too large, which is beneficial to realizing the light-weight design of the optical system 10, and the problem that the object-side surface S3 of the second lens L2 is too curved to cause too large processing difficulty can also be avoided. In some embodiments, the relationship satisfied by optical system 10 may be specifically 3.8, 4, 4.5, 6, 7.5, 8.8, 9.4, 11, 13.6, 14.8, 15.6, 15.9, or 16.2.

TTL/f is more than 7.8 and less than 9.5; TTL is an axial distance from the object-side surface S1 of the first lens element L1 to the image plane S13 of the optical system 10, and f is an effective focal length of the optical system 10. By satisfying the relationship between the total optical length and the effective focal length of the optical system 10, the total optical length of the optical system 10 can be effectively restricted while satisfying the requirement of the optical system 10 for a large field angle, thereby satisfying the miniaturization of the optical system 10. When the upper limit of the relational expression is exceeded, the total length of the optical system 10 is too long, which is not favorable for miniaturization; if the focal length of the optical system 10 is too long below the lower limit of the relational expression, it is not favorable to satisfy the requirement of the optical system 10 for the large viewing angle characteristic, and it is difficult to obtain sufficient object space information. In some embodiments, the relationship satisfied by optical system 10 may be specifically 7.9, 8.1, 8.47, 8.7, 8.9, 9, 9.14, or 9.2.

10mm < 2 x f tan (FOV/2) < 11.5 mm; f is the effective focal length of the optical system 10 and the FOV is the maximum field angle of the optical system 10. When the condition of the relational expression is satisfied, the distortion amount of the entire optical system 10 can be controlled, so that the distortion of the optical system 10 can be well suppressed, thereby improving the resolution of the optical system 10 and reducing the distortion risk of a shot picture with a large visual field range. In some embodiments, the relationship satisfied by optical system 10 may specifically be 10.25, 10.33, 10.46, 10.68, 10.85, 11.1, 11.26, or 11.33, in units of mm.

It should be noted that the reference wavelength of the parameter values in the above relational conditions is 587.56nm, and the above relational conditions and the technical effects thereof are directed to the six-piece optical system 10 having the above lens design. When the lens design (the number of lenses, the refractive power arrangement, the surface type arrangement, etc.) of the optical system 10 cannot be ensured, it is difficult to ensure that the optical system 10 can still have the corresponding technical effect while satisfying the relationships, and even the imaging performance may be significantly reduced.

The optical system 10 includes an aperture stop STO, which is used to control the amount of incoming light of the optical system 10 and can function to block non-effective light and control the size of the depth of field. In some embodiments, the stop STO can be disposed on the object side of the first lens L1, and can also be disposed between two adjacent lenses in the optical system 10.

In some embodiments, at least one lens in optical system 10 has an aspheric surface, which may be referred to as having an aspheric surface when at least one of the lens' surfaces (object-side or image-side) is aspheric. Specifically, both the object-side surface and the image-side surface of each lens may be designed to be aspherical. The aspheric surface can further help the optical system 10 to effectively eliminate aberration, improve imaging quality, and facilitate the miniaturization design of the optical system 10, so that the optical system 10 can have excellent optical effect on the premise of keeping the miniaturization design. Of course, in other embodiments, at least one lens in the optical system 10 may have a spherical surface shape, and the design of the spherical surface shape may reduce the difficulty and cost of manufacturing the lens. It should be noted that there may be some deviation in the ratios of the dimensions of the thickness, surface curvature, etc. of the respective lenses in the drawings. It should also be noted that when the object side surface or the image side surface of a lens is aspheric, the surface may have a reverse curvature, and the surface shape of the surface from the center to the edge will change.

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

The optical system 10 of the present application is described below by way of more detailed embodiments:

first embodiment

Referring to fig. 1 and 2, the first embodiment provides an optical system 10 with a six-piece structure, and the optical system 10 includes, in order from an object side to an image side along an optical axis 101, 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 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, an astigmatism diagram, and a distortion diagram of the optical system 10 in the first embodiment, wherein a reference wavelength of the astigmatism diagram and the distortion diagram is 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.

It should be noted that when a lens surface is referred to as convex, the lens surface will appear convex as a whole, but the surface may be aspherical or spherical. Similarly, when a lens surface is referred to as concave, the surface may be aspheric or spherical, but appear concave overall.

In the optical system 10, the first lens L1 and the second lens L2 are both negative lenses, so that a retrofocus lens structure can be formed, so that incident light rays having a large angle with the optical axis 101 of the optical system 10 can be effectively deflected by the first lens L1 and the second lens L2 and enter the optical system 10, and the optical system 10 has a large angle of view and even a wide angle. In addition, by matching with the positive refractive power design of the third lens element L3, the fourth lens element L4 and the fifth lens element L5, the negative refractive power contribution provided by the first lens element L1 and the second lens element L2 can be effectively balanced, so as to effectively correct the distortion caused by a large viewing angle, thereby improving the imaging quality. Further, since the object-side and image-side surfaces of the fourth lens element L4 and the fifth lens element L5 are convex, the axial dimension of the optical system 10 can be reduced, which is advantageous for compact design. The sixth lens element L6 is designed as a negative lens element, which can further balance the larger positive refractive power provided by the third lens element L3 to the fifth lens element L5, so as to further correct the aberration of the optical system 10, and simultaneously facilitate increasing the back focus of the optical system 10, so as to increase the focusing range to reduce the tolerance sensitivity when assembling with the image sensor, and facilitate increasing the propagation space after the light exits from the sixth lens element L6, thereby reducing the difficulty in designing the optical system 10 when adjusting the aberration.

In this embodiment, the lens parameters of the optical system 10 are presented in table 1 below. The elements from the object side to the image side of the system are arranged in sequence from top to bottom in table 1, wherein the diaphragm represents an aperture diaphragm. The filter 110 and the cover glass 120 may be part of the optical system 10 or may be removed from the optical system 10, but the total optical length of the optical system 110 remains unchanged after the filter 110 and the cover glass 120 are removed. Surfaces corresponding to surface numbers S1 and S2 respectively represent the object-side surface S1 and the image-side surface S2 of the first lens L1, and so on for lens surfaces corresponding to other surface numbers. The Y radius is the radius of curvature of the corresponding surface of the lens at the optical axis 101. The absolute value of the first value of the lens in the "thickness" parameter set is the thickness of the lens on the optical axis 101, and the absolute value of the second value is the distance from the image-side surface of the lens to the next optical element (lens or stop) on the optical axis 101. The thickness parameter of the diaphragm represents the distance on the optical axis 101 from the diaphragm surface to the object-side surface of the adjacent lens on the image side. The reference wavelengths of the refractive index, abbe number and focal length of each lens in the table are 587.56nm, and the numerical units of the Y radius, thickness, focal length (effective focal length) are all millimeters (mm). In addition, the parameter data and the lens surface shape structure used for the relational expression calculation in the following embodiments are subject to the data in the lens parameter table in the corresponding embodiment.

TABLE 1

As can be seen from table 1, the effective focal length f of the optical system 10 in the first embodiment is 2.03mm, the f-number FNO is 2.2, and the maximum field angle FOV is 140 °. The optical system 10 is assembled with the image sensor to form a camera module, the rectangular effective pixel area of the image sensor has a diagonal direction, and when the image sensor is assembled, the FOV can also be understood as the maximum field angle of the optical system 10 in the diagonal direction.

In addition, the object-side surface and the image-side surface of the first lens element L1 and the third lens element L3 in the first embodiment are both spherical, and both the two lens elements are made of glass. The object-side surface and the image-side surface of the second lens element L2, the fourth lens element L4, the fifth lens element L5, and the sixth lens element L6 are aspheric, and the lens elements are made of plastic, including but not limited to polycarbonate, polymethyl methacrylate, and resin. In addition, the image-side surface S10 of the fifth lens L5 is cemented with the object-side surface S11 of the sixth lens L6, and the surface shapes of the two lens surfaces are complementary.

Table 2 below presents the aspherical coefficients of the corresponding lens surfaces in table 1, where K is a conic coefficient and Ai is a coefficient corresponding to the i-th order higher-order term in the aspherical surface type formula.

TABLE 2

Number of noodles

S3

S4

S7

S8

S9

S11

S12

K

0.000E+00

-5.687E+01

5.041E-01

0.000E+00

A4

1.329E-02

2.083E-02

-4.584E-02

-2.160E-02

-5.172E-02

-1.034E-01

-8.163E-03

A6

-4.883E-04

-1.908E-03

-1.075E-03

-2.844E-04

6.360E-03

5.873E-02

2.823E-03

A8

1.009E-04

2.221E-03

-3.680E-04

1.329E-04

-5.801E-04

-3.217E-03

-1.241E-03

A10

-3.325E-06

-1.156E-04

-1.075E-04

-1.052E-04

2.093E-04

2.937E-04

1.740E-05

A12

0.000E+00

-3.369E-22

-2.902E-22

5.284E-21

0.000E+00

A14

0.000E+00

A16

0.000E+00

A18

0.000E+00

A20

0.000E+00

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

f1/CT1 ═ -7.991; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 at the optical axis 101. When the above-mentioned lens refractive power and surface design are satisfied and the above-mentioned relation conditions are satisfied, on one hand, the center thickness of the first lens element L1 is prevented from being too small, so as to reduce the tolerance sensitivity of the center thickness of the first lens element L1, thereby reducing the difficulty of the processing technology of the first lens element L1, and further being beneficial to improving the assembly yield of the lens and further reducing the production cost; on the other hand, the negative refractive power of the first lens element L1 can be controlled within a reasonable range, so that astigmatism that is hard to correct is prevented from being generated in the optical system 10 due to the fact that the refractive power of the first lens element L1 is too large, and the optical system 10 has good imaging quality; meanwhile, the optical system 10 is advantageous to have a wide-angle characteristic, and the problem of an excessively small angle of view caused by insufficient refractive power of the first lens element L1 is avoided.

D/(2*Imgh*FOV)＝0.0111deg^-1(ii) a D is the maximum effective light-passing aperture of the object-side surface S1 of the first lens L1, Imgh is half the image height corresponding to the maximum angle of view of the optical system 10, and FOV is the maximum angle of view of the optical system 10. When this relational condition is satisfied, the object side end of the optical system 10 can be made to have a small aperture characteristic, and thus a small head design can be realized.

3 < Imgh/EPD < 4; imgh is half the image height corresponding to the maximum field angle of the optical system 10, and EPD is the entrance pupil diameter of the optical system 10. When the relational expression condition is satisfied, it is advantageous to increase the image plane brightness of the optical system 10 and to increase the field angle, so that the optical system 10 has a wide-angle characteristic.

f3/f 6.267; f3 is the effective focal length of the third lens L3, and f is the effective focal length of the optical system 10. Since the incident light ray first passes through the first lens element L1 and the second lens element L2 with strong negative refractive power, it is easy to cause the edge light ray to have large curvature of field when reaching the image plane S13. By providing the third lens element L3 with positive refractive power, and when the relationship is satisfied, the refractive power of the third lens element L3 can be configured reasonably, which is beneficial to balance the aberration caused by the stronger negative refractive power of the first lens element L1 and the second lens element L2, i.e., the peripheral aberration of the optical system 10 can be corrected, and the imaging resolution can be improved.

(D12+ CT2)/(CT3+ D34) ═ 0.812; d12 is the distance on the optical axis from the image-side surface S2 of the first lens element L1 to the object-side surface S3 of the second lens element L2, CT2 is the thickness of the second lens element L2 on the optical axis, CT3 is the thickness of the third lens element L3 on the optical axis, and D34 is the distance on the optical axis from the image-side surface S6 of the third lens element L3 to the object-side surface S7 of the fourth lens element L4. When the condition of the relational expression is satisfied, the thicknesses of the second lens L2 and the third lens L3 and the distance between the second lens L2 and the third lens L3 and the adjacent lens can be mutually constrained, the size of the object end structure of the optical system 10 can be reasonably controlled, on one hand, the structural compactness of the optical system 10 is favorably improved, and the requirement on miniaturization design is satisfied; on the other hand, the incident light can have a reasonable transition space when passing through the front four lenses of the optical system 10, thereby being beneficial to correcting system aberration and improving imaging resolution.

f56/f 4.426; f56 is the combined focal length of the fifth lens L5 and the sixth lens L6, f is the effective focal length of the optical system 10, and wherein the fifth lens L5 is cemented with the sixth lens L6. The fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative refractive power can correct the aberrations of the two lens elements by gluing them together. Meanwhile, the requirements of the relational expression are satisfied, which is also beneficial to correcting the problems of the edge aberration, chromatic aberration, astigmatism and the like of the optical system 10.

-2.38 for f 123/f; f123 is a combined focal length of the first lens L1, the second lens L2, and the third lens L3, and f is an effective focal length of the optical system 10, wherein the optical system 10 includes an aperture stop disposed between the third lens L3 and the fourth lens L4. When the relational condition is satisfied, the front lens group located at the object space of the aperture diaphragm integrally provides negative refractive power for the optical system 10, so that the light rays incident at a large angle can pass through the aperture diaphragm, the wide-angle design of the optical system 10 is realized, and the image surface brightness of the optical system 10 with a large-angle view field is improved.

R3/CT2 ═ 9.323; r3 is the radius of curvature of the object-side surface S3 of the second lens L2 at the optical axis, and CT2 is the thickness of the second lens L2 at the optical axis. The object-side surface S3 of the second lens element L2 is convex at a paraxial region, the image-side surface S4 is concave at a paraxial region, and the entire structure of the second lens element L2 is meniscus-shaped, so that light can be further converged, and contraction of incident light is facilitated. Meanwhile, by satisfying the above-mentioned relation conditions to reasonably arrange the thickness and the surface shape of the second lens L2, the thickness of the second lens L2 can be prevented from being too large, which is beneficial to realizing the light-weight design of the optical system 10, and the problem that the object-side surface S3 of the second lens L2 is too curved to cause too large processing difficulty can also be avoided.

TTL/f is 8.329; TTL is an axial distance from the object-side surface S1 of the first lens element L1 to the image plane S13 of the optical system 10, and f is an effective focal length of the optical system 10. By satisfying the relationship between the total optical length and the effective focal length of the optical system 10, the total optical length of the optical system 10 can be effectively restricted while satisfying the requirement of the optical system 10 for a large field angle, thereby satisfying the miniaturization of the optical system 10.

2 f tan (FOV/2) 11.153 mm; f is the effective focal length of the optical system 10 and the FOV is the maximum field angle of the optical system 10. When the condition of the relational expression is satisfied, the distortion amount of the entire optical system 10 can be controlled, so that the distortion of the optical system 10 can be well suppressed, thereby improving the resolution of the optical system 10 and reducing the distortion risk of a shot picture with a large visual field range.

Fig. 2 includes a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of optical system 10, which shows the convergent focus deviation of light rays of different wavelengths through the lens. The ordinate of the longitudinal spherical aberration diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa represents the distance (in mm) of the imaging plane from the intersection of the ray with the optical axis 101. It can be known from the longitudinal spherical aberration diagram that the convergent focus deviation degrees of the light rays with the wavelengths in the first embodiment are small and tend to be consistent, and the diffuse speckles or color halos in the imaging picture are effectively suppressed. In particular, the longitudinal spherical aberration of the infrared light with a wavelength of 940nm in the optical system 10 can be well adjusted, and the deviation degree of the convergent focus is small and tends to be consistent with the deviation degree of the convergent focus under each visible light wavelength, so that the optical system 10 can be suitable for imaging visible light and near infrared light, namely, can be used for both day and night. Therefore, in some embodiments, the filter disposed on the image side of the sixth lens element L6 may be a bandpass filter, which allows 390nm to 950nm light to pass through, so that a good image formation can be achieved by one camera module in the daytime and at night. In other embodiments, a filter may be provided that allows only visible light or only near infrared light to pass through.

FIG. 2 also includes a Field curvature map (statistical Field Curves) of optical system 10, where the S curve represents sagittal Field curvature at 587.56nm and the T curve represents meridional Field curvature at 587.56 nm. As can be seen from the figure, the meridional and sagittal curvature field of the system is small, the maximum curvature field is controlled within 0.05mm, and the distance between the meridional curvature field and the sagittal curvature field in each field is small, so that the curvature field and astigmatism of each field are well corrected, the imaging curvature is not obvious, and the center and the edge of each field can have clear imaging. Fig. 2 also includes a Distortion map (Distortion) of the optical system 10, and it can be seen that the image Distortion caused by the main beam is small and the imaging quality of the system is excellent.

Second embodiment

Referring to fig. 3 and 4, the optical system 10 in the second embodiment includes, in order from an object side to an image side along an optical axis 101, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a stop STO, a third lens element L3 with positive refractive power, 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. 4 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in this embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

The object-side surface S11 of the sixth lens element L6 is concave, and the image-side surface S12 is convex. Wherein the fifth lens L5 and the sixth lens L6 constitute a cemented lens.

The lens parameters of the optical system 10 in the second embodiment are shown in tables 3 and 4, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which are not repeated herein. The reference wavelength for each lens parameter was 587.56 nm.

TABLE 3

TABLE 4

Number of noodles

S3

S4

S7

S8

S9

S11

S12

K

0.000E+00

3.041E+00

5.041E-01

0.000E+00

A4

1.329E-02

2.083E-02

-1.569E+02

-2.160E-02

-1.172E-02

-1.034E-01

-8.163E-03

A6

-4.883E-04

-1.908E-03

-1.584E-02

-1.844E-04

1.360E-03

5.873E-02

6.823E-03

A8

1.009E-04

1.221E-03

-4.075E-03

1.329E-04

-5.801E-04

-4.217E-03

-1.241E-03

A10

-6.325E-06

-1.156E-04

-6.680E-04

-1.052E-04

2.093E-04

2.937E-04

7.740E-05

A12

0.000E+00

-5.075E-04

-3.902E-22

1.284E-21

0.000E+00

A14

0.000E+00

-3.369E-22

0.000E+00

A16

0.000E+00

A18

0.000E+00

A20

0.000E+00

The camera module 10 in this embodiment satisfies the following relationship:

f1/CT1	-7.991	f56/f	4.426
				D/(2ImghFOV)(deg^-1)	0.011110	f123/f	-2.380
Imgh/EPD	3.296	R3/CT2	9.323
				f3/f	6.267	TTL/f	8.344
(D12+CT2)/(CT3+D34)	0.812	2ftan(FOV/2)(mm)	11.153

as can be seen from the aberration diagrams in fig. 4, the longitudinal spherical aberration, curvature of field, astigmatism, and distortion of the optical system 10 are all well controlled, thereby illustrating that the optical system 10 of this embodiment has good imaging quality.

Third embodiment

Referring to fig. 5 and 6, the optical system 10 in the third embodiment includes, in order from an object side to an image side along an optical axis 101, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a stop STO, a third lens element L3 with positive refractive power, 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. 6 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in this embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

The lens parameters of the optical system 10 in the third embodiment are shown in tables 5 and 6, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which are not repeated herein. The reference wavelength for each lens parameter was 587.56 nm.

TABLE 5

TABLE 6

Number of noodles

S3

S4

S7

S8

S9

S11

S12

K

0.000E+00

-2.529E+01

8.869E-01

0.000E+00

A4

1.355E-02

2.087E-02

-1.566E-02

-2.380E-02

-1.435E-02

-1.063E-01

-9.038E-03

A6

-1.020E-03

-6.257E-03

-4.471E-03

-5.261E-05

1.395E-03

5.949E-02

6.866E-03

A8

1.117E-04

1.290E-03

-2.422E-04

2.016E-04

-6.026E-04

-1.509E-03

-1.259E-03

A10

-7.147E-06

-3.340E-04

-2.320E-04

-1.335E-04

2.183E-04

3.148E-04

7.994E-05

A12

0.000E+00

-3.393E-22

-8.605E-22

5.452E-21

0.000E+00

A14

0.000E+00

A16

0.000E+00

A18

0.000E+00

A20

0.000E+00

The camera module 10 in this embodiment satisfies the following relationship:

f1/CT1	-7.903	f56/f	4.238
				D/(2ImghFOV)(deg^-1)	0.011043	f123/f	-2.227
Imgh/EPD	3.301	R3/CT2	8.251
				f3/f	6.983	TTL/f	8.358
(D12+CT2)/(CT3+D34)	0.787	2ftan(FOV/2)(mm)	11.153

as can be seen from the aberration diagrams of fig. 6, the longitudinal spherical aberration, curvature of field, astigmatism, and distortion of the optical system 10 are all well controlled, thereby illustrating that the optical system 10 of this embodiment has good imaging quality.

Fourth embodiment

Referring to fig. 7 and 8, the optical system 10 in the fourth embodiment includes, in order from an object side to an image side along an optical axis 101, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a stop STO, a third lens element L3 with positive refractive power, 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. 8 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in this embodiment, where the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

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

The lens parameters of the optical system 10 in the fourth embodiment are shown in tables 7 and 8, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which is not repeated herein. The reference wavelength for each lens parameter was 587.56 nm.

TABLE 7

TABLE 8

Number of noodles

S3

S4

S5

S6

S9

S11

S12

K

0.000E+00

1.623E+01

A4

1.364E-02

3.068E-02

2.091E-02

2.529E-02

4.217E-03

-5.006E-02

4.614E-03

A6

-1.611E-03

1.093E-03

1.039E-04

4.912E-03

-9.618E-04

4.991E-02

1.422E-03

A8

1.447E-05

-1.689E-05

1.524E-04

-4.978E-04

1.914E-04

-1.870E-02

-1.230E-03

A10

-1.505E-07

-2.657E-04

-2.197E-04

2.059E-04

-1.156E-04

2.968E-03

1.326E-04

A12

0.000E+00

1.019E-18

0.000E+00

-2.755E-20

A14

0.000E+00

A16

0.000E+00

A18

0.000E+00

A20

0.000E+00

The camera module 10 in this embodiment satisfies the following relationship:

f1/CT1	-9.086	f56/f	12.386
				D/(2ImghFOV)(deg^-1)	0.011171	f123/f	-1.439
Imgh/EPD	3.346	R3/CT2	16.458
				f3/f	9.283	TTL/f	7.810
(D12+CT2)/(CT3+D34)	1.516	2ftan(FOV/2)(mm)	11.208

as can be seen from the aberration diagrams of fig. 8, the longitudinal spherical aberration, curvature of field, astigmatism, and distortion of the optical system 10 are all well controlled, thereby illustrating that the optical system 10 of this embodiment has good imaging quality.

Fifth embodiment

Referring to fig. 9 and 10, the optical system 10 in the fifth embodiment includes, in order from an object side to an image side along an optical axis 101, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a stop STO, a third lens element L3 with positive refractive power, 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. 10 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in this embodiment, where the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

The lens parameters of the optical system 10 in the fifth embodiment are shown in tables 9 and 10, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which are not described herein. The reference wavelength for each lens parameter was 587.56 nm.

TABLE 9

Watch 10

Number of noodles

3

4

5

6

10

11

12

K

0.000E+00

-2.357E-01

1.456E+00

A4

1.853E-02

3.126E-02

1.532E-02

1.896E-02

2.083E-03

-2.402E-02

1.276E-02

A6

-1.714E-03

-2.517E-03

-1.461E-05

7.247E-03

-1.791E-03

1.842E-02

6.254E-03

A8

2.432E-04

5.234E-03

7.593E-04

5.762E-04

1.016E-03

-1.523E-02

-7.812E-04

A10

-1.597E-05

-4.039E-04

-1.989E-04

-3.234E-06

-2.227E-04

2.423E-03

8.707E-05

A12

3.088E-17

-1.175E-21

-6.157E-21

-1.462E-22

1.018E-18

1.161E-19

9.014E-19

A14

0.000E+00

A16

0.000E+00

A18

0.000E+00

A20

0.000E+00

The camera module 10 in this embodiment satisfies the following relationship:

as can be seen from the aberration diagrams of fig. 10, the longitudinal spherical aberration, curvature of field, astigmatism, and distortion of the optical system 10 are all well controlled, thereby illustrating that the optical system 10 of this embodiment has good imaging quality.

Sixth embodiment

Referring to fig. 11 and 12, the optical system 10 in the sixth embodiment includes, in order from an object side to an image side along an optical axis 101, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a stop STO, a third lens element L3 with positive refractive power, 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. 12 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in this embodiment, in which the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

The lens parameters of the optical system 10 in the sixth embodiment are given in tables 11 and 12, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which are not described herein. The reference wavelength for each lens parameter was 587.56 nm.

TABLE 11

TABLE 12

The camera module 10 in this embodiment satisfies the following relationship:

f1/CT1	-7.105	f56/f	4.970
				D/(2ImghFOV)(deg^-1)	0.010615	f123/f	-1.763
Imgh/EPD	3.715	R3/CT2	3.754
				f3/f	12.090	TTL/f	9.337
(D12+CT2)/(CT3+D34)	1.356	2ftan(FOV/2)(mm)	11.401

as can be seen from the aberration diagrams in fig. 12, the longitudinal spherical aberration, curvature of field, astigmatism, and distortion of the optical system 10 are all well controlled, thereby illustrating that the optical system 10 of this embodiment has good imaging quality.

With the optical system 10 in each of the above embodiments, by adopting the above lens refractive power and surface design, the optical system 10 can achieve good correction of aberration while having a large viewing angle characteristic, thereby achieving good imaging quality. In addition, the intensity of the negative refractive power of the first lens element L1 can be controlled within a reasonable range, so as to avoid the occurrence of astigmatism that is difficult to correct in the optical system 10 due to the excessive intensity of the refractive power of the first lens element L1, thereby being beneficial to the optical system 10 having good imaging quality (referring to the astigmatism diagrams in the embodiments, the astigmatism in each field is controlled within 0.05 mm). Meanwhile, the above optical system 10 also possesses a wide-angle characteristic. In particular, according to the longitudinal spherical aberration of each embodiment, the longitudinal spherical aberration of the infrared light with the wavelength of 940nm in the optical system 10 can be well adjusted, and the deviation degree of the convergent focus is small and tends to be consistent with the deviation degree of the convergent focus at each visible light wavelength, so that the optical system 10 can be suitable for imaging visible light and near infrared light, that is, can realize day and night use. When the optical system 10 is applied to the vehicle-mounted camera device, when the automobile drives from an environment with sufficient light into an environment with a dark environment such as an underground garage and a tunnel, the vehicle-mounted camera device can still obtain good imaging through the optical system 10.

Referring to fig. 13, the present application further provides a camera module 20 in some embodiments, where the camera module 20 includes an optical system 10 and an image sensor 210, and the image sensor 210 is disposed on an image side of the optical system 10. The image sensor 210 may be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). In general, when assembling, the imaging surfaces S13 of the optical system 10 are overlapped with each other, the effective pixel areas on the photosensitive surfaces are generally rectangular, and the maximum field angle corresponding to the diagonal direction of the rectangular effective pixel area is the maximum field angle of the optical system 10. By adopting the optical system 10, the camera module 20 will have a large viewing angle characteristic and at the same time can have good shooting quality.

In some embodiments, the camera module 20 includes a filter 110 disposed between the optical system 10 and the image sensor 210. In one embodiment, the filter 110 may be a band pass filter, which allows visible light and near infrared light to pass through, so that a good image can be obtained by one camera module 20 in both daytime and at night, thereby achieving dual purposes of day and night and reducing the cost of the camera device.

In some embodiments, the camera module 20 further includes a protective glass 120, the protective glass 120 is disposed between the optical filter 110 and the image sensor 210, and the protective glass 120 is used for protecting the image sensor 210.

Referring to fig. 14, some embodiments of the present application 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 protective shell, or the like. The electronic device 30 includes, but is not limited to, a vehicle-mounted image pickup device, an aircraft image pickup device, a monitoring image pickup device, and the like that can cooperate with the vehicle-mounted auxiliary system.

For example, in some embodiments, the electronic device 30 is a vehicle-mounted camera device, and the camera module 20 is disposed in the fixture 310 of the vehicle-mounted camera device. In some embodiments, the electronic device 30 further includes a mounting plate 320, the fixing member 310 is rotatably connected to the mounting plate 320, and the mounting plate 320 is configured to be fixed to a vehicle body. The electronic device 30 may cooperate with at least one of an assistant driving system, an automatic driving system, and a display screen to transmit the obtained image information to the terminal to judge the state and road condition of the driver, or directly display the image on the display screen for the driver to observe. By adopting the camera module 20, the electronic device 30 can have good shooting quality, so that the electronic device can be better matched with a vehicle-mounted auxiliary system.

Referring to fig. 15, some embodiments of the present application also provide an automobile 40. The automobile 40 includes the mounting portion 410 and the electronic device 30, and the electronic device 30 is provided in the mounting portion 410. The mounting portion 410 may be a front grille, a rear view mirror, a left rear view mirror, a right rear view mirror, a roof, a trunk lid, or the like, which is suitable for mounting the image pickup apparatus. By adopting the electronic device 30 with the optical system 10, the automobile 40 can obtain clearer driver states and road conditions, so that the recognition accuracy of the vehicle-mounted auxiliary system on the image can be improved, more accurate safety early warning can be given, and the driving safety can be improved.

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 along an optical axis:

a first lens element with negative refractive power;

a sixth lens element with negative refractive power;

the optical system further satisfies the relationship:

-9.1＜f1/CT1＜-7；

2. The optical system of claim 1, wherein the optical system satisfies the relationship:

0＜D/(2*Imgh*FOV)≤0.04deg^-1；

d is a maximum effective clear aperture of the object-side surface of the first lens element, Imgh is half an image height corresponding to a maximum field angle of the optical system, and FOV is the maximum field angle of the optical system.

3. The optical system of claim 1, wherein the optical system satisfies the relationship:

3＜Imgh/EPD＜4；

imgh is half the image height corresponding to the maximum field angle of the optical system, and EPD is the entrance pupil diameter of the optical system.

4. The optical system of claim 1, wherein the optical system satisfies the relationship:

6＜f3/f＜13；

f3 is the effective focal length of the third lens, and f is the effective focal length of the optical system.

5. The optical system of claim 1, wherein the optical system satisfies the relationship:

0.6＜(D12+CT2)/(CT3+D34)＜1.6；

d12 is a distance on an optical axis from an image-side surface of the first lens element to an object-side surface of the second lens element, CT2 is a thickness of the second lens element on the optical axis, CT3 is a thickness of the third lens element on the optical axis, and D34 is a distance on the optical axis from the image-side surface of the third lens element to an object-side surface of the fourth lens element.

6. The optical system of claim 1, wherein the fifth lens is cemented to the sixth lens, and the optical system satisfies the relationship:

4.2＜f56/f＜12.5；

f56 is the combined focal length of the fifth lens and the sixth lens, and f is the effective focal length of the optical system.

7. The optical system according to claim 1, wherein the optical system includes an aperture stop provided between the third lens and the fourth lens, and the optical system satisfies a relationship:

-2.4＜f123/f＜-1.4；

f123 is a combined focal length of the first lens, the second lens and the third lens, and f is an effective focal length of the optical system.

8. The optical system of claim 1, wherein the optical system satisfies the relationship:

3.5＜R3/CT2＜16.5；

r3 is the radius of curvature of the object-side surface of the second lens at the optical axis, and CT2 is the thickness of the second lens at the optical axis.

9. The optical system of claim 1, wherein the optical system satisfies the relationship:

7.8＜TTL/f＜9.5；

TTL is a distance on an optical axis from an object-side surface of the first lens element to an imaging surface of the optical system, and f is an effective focal length of the optical system.

10. The optical system of claim 1, wherein the optical system satisfies the relationship:

10mm＜2*f*tan(FOV/2)＜11.5mm；

f is the effective focal length of the optical system, and the FOV is the maximum field angle of the optical system.

11. A camera module, comprising an image sensor and the optical system of any one of claims 1 to 10, wherein the image sensor 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 mounting portion and the electronic device of claim 12, wherein the electronic device is provided in the mounting portion.