CN214474190U

CN214474190U - Optical system, camera module and electronic equipment

Info

Publication number: CN214474190U
Application number: CN202120388407.1U
Authority: CN
Inventors: 徐标; 李明; 宋琦
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2021-10-22
Anticipated expiration: 2031-02-22

Abstract

The utility model relates to an optical system, module and electronic equipment make a video recording. The optical system includes, in order from an object side to an image side along an optical axis: a first lens element with positive refractive power having a convex object-side surface and a concave image-side surface; a second lens element with negative refractive power having a concave image-side surface at paraxial region; a third lens; a fourth lens; a fifth lens element with negative refractive power having a concave image-side surface at the paraxial region and an inflection point on the image-side surface; the optical system satisfies the relationship: f12/f is more than or equal to 1.0 and less than or equal to 1.25; f12 is the combined focal length of the first and second lenses, and f is the effective focal length of the optical system. The optical system can effectively balance the refractive power distribution of the front lens group in the whole optical system, and the imaging quality of the system is improved; and the field range of the optical system can be enlarged.

Description

Optical system, camera module and electronic equipment

Technical Field

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

Background

With the development of the photographic imaging technology, the imaging lens and the image sensor in the camera module are greatly improved, but the market demand for high shooting performance of the electronic equipment still only increases.

At present, the five-piece imaging lens can obtain better balance in the preparation cost and the imaging quality, and has further development space in the aspects of reducing the preparation difficulty and the cost, improving the imaging quality and the like. Particularly, in response to the further demand of the market for shooting performance, how to further modify the five-lens imaging lens to improve the imaging quality thereof is also one of the important points of interest in the industry.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is necessary to provide an optical system, an image pickup module, and an electronic apparatus, which are directed to the problem of how to improve 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 positive refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region;

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

a third lens element with refractive power;

a fourth lens element with refractive power;

a fifth lens element with negative refractive power having a concave image-side surface at the paraxial region and an inflection point on the image-side surface;

the optical system satisfies the relationship:

1.0≤f12/f≤1.25；

f12 is the combined focal length of the first and second lenses, and f is the effective focal length of the optical system.

In the optical system, the first lens element provides positive refractive power, which is beneficial for the large aperture system to acquire object space information to obtain a larger field of view and shorten the length of the system, and the second lens element to the fifth lens element are configured to balance the aberration generated by the first lens element through the refractive power and the surface shape. When the above relation condition is further satisfied, the refractive power strength of the front lens group composed of the first lens and the second lens can be reasonably controlled, so that the refractive power distribution of the front lens group in the whole optical system is effectively balanced, the aberration generated by the rear lens group composed of the third lens to the fifth lens is balanced, the problem that the rear lens group is difficult to realize correction due to the fact that the front lens group generates large aberration due to too strong refractive power is avoided, and the imaging quality of the system can be improved; meanwhile, the front lens group has enough positive refractive power to effectively converge the light rays incident from the object space, so that the field range of the optical system is enlarged.

In one embodiment, the optical system satisfies the relationship:

0.4≤SAG41/CT4≤1.0；

SAG41 is the sagittal height of the object side of the fourth lens at the maximum effective aperture, and CT4 is the thickness of the fourth lens on the optical axis. When the relation is met, the object side surface type and the lens thickness of the fourth lens can be reasonably controlled, so that the fourth lens can be driven to be not excessively bent on the whole structure, the processing and forming of the lens are facilitated, the manufacturing sensitivity is reduced, and the engineering manufacturing is better realized; meanwhile, the surface shape of the fourth lens is not too gentle, so that the fourth lens which is one of the last two lenses of the system can well adjust the astigmatism of the marginal field of view.

In one embodiment, the optical system satisfies the relationship:

1.0≤CT3/ET3≤1.5；

CT3 is the thickness of the third lens element along the optical axis, and ET3 is the distance from the maximum effective aperture at the object side to the maximum effective aperture at the image side along the optical axis of the third lens element. When the relation is met, on one hand, the processing and forming of the third lens are facilitated, and the assembling difficulty is reduced; on the other hand, the field curvature of the system can be effectively corrected, and the imaging quality of the system is improved.

In one embodiment, the optical system satisfies the relationship:

20≤|V4-V3|≤28；

v3 is the Abbe number of the third lens, and V4 is the Abbe number of the fourth lens. When the relation is met, the abbe numbers of the third lens and the fourth lens can be controlled within a reasonable range, so that the aberration of the system can be improved, achromatization is facilitated, the secondary spectrum of the system is reduced, and the imaging performance of the system is improved.

In one embodiment, the optical system satisfies the relationship:

TTL/Imgh≤1.4；

TTL is a distance on an optical axis from an object-side surface of the first lens element to an image plane of the optical system, and Imgh is half of an image height corresponding to a maximum field angle of the optical system. When the relation is satisfied, on one hand, the optical system has the ultra-thin characteristic, and the design requirement of system miniaturization can be realized; on the other hand, the optical system can also have large image surface characteristics, so that the optical system can be matched with an image sensor with higher pixels.

In one embodiment, the optical system satisfies the relationship:

2≤|f2/f4|≤4；

f2 is the effective focal length of the second lens, and f4 is the effective focal length of the fourth lens. When the relationship is satisfied, the contribution of the refractive powers of the second lens element and the fourth lens element in the optical system can be reasonably distributed, so that the difference of the refractive powers borne by the second lens element and the fourth lens element is reasonable and cannot be too large, and the refractive powers can be well balanced, thereby preventing the excessive sensitivity of the lens element caused by the excessive concentration of the refractive power on one of the lens elements, further preventing the generation of field curvature, and improving the imaging quality.

In one embodiment, the optical system satisfies the relationship:

Fno≤1.9；

fno is the f-number of the optical system. When the relation is met, the characteristic that the system has a large aperture can be ensured, the optical system has enough light incoming quantity, imaging is clearer, and high-quality imaging of low-brightness object space scenes such as night scenes, starry sky scenes and the like can be realized.

In one embodiment, the optical system satisfies the relationship:

0.4≤R9/R10≤1；

r9 is a radius of curvature of an image-side surface of the fourth lens element at an optical axis, and R10 is a radius of curvature of an object-side surface of the fifth lens element at the optical axis. When the relationship is satisfied, the surface type between the image side surface of the fourth lens and the object side surface of the fifth lens can be reasonably configured, and the exit angle of light on the image side surface of the fourth lens and the incident angle on the object side surface of the fifth lens can be reasonably reduced, so that the influence of the tolerance in the optical system on the field of view is reduced, namely, the tolerance sensitivity of the field of view can be reduced, and the yield of the system is improved.

In one embodiment, the optical system satisfies the relationship:

0.5≤D4/CT5≤2.0；

d4 is an axial distance between an image-side surface of the fourth lens element and an object-side surface of the fifth lens element, and CT5 is an axial thickness of the fifth lens element. When the relation is satisfied, the ratio of the spacing distance between the fourth lens and the fifth lens to the thickness of the fifth lens can be controlled in a reasonable range, so that the high-grade aberration generated by the system can be effectively balanced, the field curvature adjustment in engineering manufacturing is facilitated, and the imaging quality of the system is improved.

In one embodiment, the optical system satisfies the relationship:

0.8≤f1/f≤1.0；

f1 is the effective focal length of the first lens. When the relationship is satisfied, the contribution of the refractive power of the first lens in the system can be reasonably distributed, on one hand, the first lens can better converge light rays incident from an object space, so that the field range of the optical system is improved, the total length of the optical system is shortened, on the other hand, the first lens can be prevented from generating overlarge aberration, and the system has good imaging quality.

In one embodiment, the optical system satisfies the relationship:

1.0≤TTL/f≤1.5；

TTL is a distance on the optical axis from the object-side surface of the first lens element to the imaging surface of the optical system. When the above relationship is satisfied, the length of the optical system can be advantageously reduced, and the optical system can be prevented from having an excessively large angle of view, thereby achieving a balance between the compact design and the reduction of aberration in a large field of view. When the optical length is less than the lower limit of the relationship, the optical length of the optical system is too short, which causes the problem of increasing the sensitivity of the system, and causes difficulty in aberration correction; or the field angle of the system is too small to satisfy the large field characteristic. When the optical length is higher than the upper limit of the above relationship, the optical length of the optical system is too long, which is not favorable for miniaturization design, and the light of the marginal field of view is difficult to image on the effective imaging area of the imaging surface, thereby causing incomplete imaging information.

In one embodiment, the optical system satisfies the relationship:

1.3mm≤Imgh²/(TTL*Fno)≤2.0mm；

the image height corresponding to the maximum field angle of the optical system is half, TTL is a distance on an optical axis from the object-side surface of the first lens element to the image plane of the optical system, and Fno is an f-number of the optical system. When the relation is satisfied, the maximum image height, the total optical length and the f-number of the optical system can be reasonably configured, so that the length of the system can be effectively compressed to realize miniaturization design, and meanwhile, the system can have large image surface characteristics and sufficient light inlet quantity, and further the imaging quality is improved. In addition, when the relation is satisfied, the optical system is further favorable to have large view field characteristics so as to obtain more object space information.

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 optical system can realize good correction on aberration, so that the imaging quality of the camera module can be improved by adopting the optical system.

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, electronic equipment can possess good shooting performance.

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.

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 "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not 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.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

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. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, an optical system 10 with a five-piece structure is provided in an embodiment of the present application, and the optical system 10 includes, in order from an object side to an image side along an optical axis 101, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5. The lenses in the optical system 10 are coaxially arranged, that is, the optical axes of the lenses are all located on the same straight line, which may be referred to as the optical axis 101 of the optical system 10. Each of the above optical elements in the optical system 10 may be assembled with a lens barrel to constitute an imaging lens.

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, and the fifth lens L5 includes an object side surface S9 and an image side surface S10. The optical system 10 further has an imaging plane S11, and the imaging plane S11 is located on the image side of the fifth lens L5. Generally, the imaging surface S11 of the optical system 10 coincides with the photosensitive surface of the image sensor, and for the sake of understanding, the imaging surface S11 may be regarded as the photosensitive surface of the image sensor.

In the present embodiment, the first lens element L1 with positive refractive power has a convex object-side surface S1 at a paraxial region and a concave image-side surface S2 at a paraxial region; the second lens element L2 with negative refractive power has a concave image-side surface at paraxial region; the fifth lens element L5 with negative refractive power has a concave image-side surface S10 at paraxial region and a inflection point on the image-side surface S10. In the optical system 10, the first lens element L1 provides positive refractive power, which is favorable for obtaining object space information by a large aperture system to obtain a larger field of view and shorten the length of the system, and the second lens element L2 to the fifth lens element L5 are configured by the above-mentioned refractive power and surface shape to balance the aberration generated by the first lens element L1.

It should be noted that when the embodiments of the present application describe a surface of a lens as being convex at a paraxial region, it can be understood that the region of the surface of the lens near the optical axis 101 is convex; when a surface of a lens is described as concave near the maximum effective aperture or at the circumference, it is understood that the area of the surface near the maximum effective aperture is concave. For example, when the surface is convex at the paraxial region and also convex at the peripheral region, the shape of the surface from the center (optical axis) to the edge direction may be purely convex; or first transition from a central convex shape to a concave shape and then become convex near the maximum effective aperture. The concavo-convex profile in the present application describes a profile of an effective light transmission region only for the corresponding lens surface.

In an embodiment of the present application, the optical system 10 further satisfies the relational condition:

f12/f is more than or equal to 1.0 and less than or equal to 1.25; f12 is the combined focal length of the first lens L1 and the second lens L2, and f is the effective focal length of the optical system 10. When the five-piece optical system 10 with the above refractive power and surface design further satisfies the relation condition, the refractive power strength of the front lens group composed of the first lens L1 and the second lens L2 can be reasonably controlled, so that the refractive power distribution of the front lens group in the whole optical system 10 is effectively balanced, the aberrations generated by the rear lens group composed of the third lens L3 to the fifth lens L5 are balanced, the problem that the rear lens group is difficult to correct due to the large aberrations generated by the front lens group due to the excessively strong refractive power is avoided, and the imaging quality of the system can be improved; meanwhile, the front lens group has enough positive refractive power to effectively converge the light incident from the object, thereby enlarging the field range of the optical system 10. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.18, 1.19, 1.2, 1.21, 1.22, or 1.23.

Furthermore, in some embodiments, the optical system 10 further satisfies at least one of the following relationships, and when either relationship is satisfied, the corresponding technical effect is brought about:

SAG41/CT4 is more than or equal to 0.4 and less than or equal to 1.0; SAG41 is the saggital height of the object side S7 of the fourth lens L4 at the maximum effective aperture, CT4 is the thickness of the fourth lens L4 on the optical axis. It should be noted that the rise of the object-side surface S7 of the fourth lens L4 at the maximum effective aperture should be understood as: the distance from the intersection of the object side surface S7 and the optical axis 101 to the plane' S maximum effective aperture in the direction parallel to the optical axis. When SAG41 is positive, it represents that the maximum effective aperture position of the object-side surface S7 of the fourth lens L4 is closer to the object side than the position where the surface intersects the optical axis 101, i.e., the surface is a low-centered high-edge surface. When the relation is met, the object side S7 surface shape and the lens thickness of the fourth lens L4 can be reasonably controlled, so that the fourth lens L4 can be driven to be not excessively bent on the whole structure, the processing and forming of the lenses are facilitated, the manufacturing sensitivity is reduced, and the engineering manufacturing is better realized; meanwhile, the surface shape of the fourth lens L4 is not too gentle, so that the fourth lens L4, which is one of the last two lenses of the system, can realize good adjustment on astigmatism of the marginal field of view. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.56, 0.58, 0.6, 0.62, 0.64, or 0.66.

CT3/ET3 is more than or equal to 1.0 and less than or equal to 1.5; CT3 is the thickness of the third lens element L3 along the optical axis, and ET3 is the distance from the maximum effective aperture of the third lens element L3 at the object side S5 to the maximum effective aperture of the image side S6 along the optical axis. When the relation is met, on one hand, the processing and molding of the third lens L3 are facilitated, and the assembly difficulty is reduced; on the other hand, the field curvature of the system can be effectively corrected, and the imaging quality of the system is improved. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.24, 1.25, 1.28, 1.3, 1.32, 1.33, or 1.35.

V4-V3 is more than or equal to 20 and less than or equal to 28; v3 is the abbe number of the third lens L3, and V4 is the abbe number of the fourth lens L4. When the above relation is satisfied, the abbe numbers of the third lens L3 and the fourth lens L4 can be controlled within a reasonable range, so that the aberration of the system can be improved, achromatization is facilitated, the secondary spectrum of the system is reduced, and the imaging performance of the system is improved.

TTL/Imgh is less than or equal to 1.4; TTL is the distance on the optical axis from the object-side surface S2 of the first lens element L1 to the image plane S11 of the optical system 10, and Imgh is half the image height corresponding to the maximum field angle of the optical system 10. When the above relationship is satisfied, on the one hand, the optical system 10 can have an ultra-thin characteristic, and the design requirement of system miniaturization can be realized; on the other hand, the optical system 10 can also be made to have a large image plane characteristic, thereby enabling matching with an image sensor of a higher pixel.

The absolute value of f2/f4 is more than or equal to 2 and less than or equal to 4; f2 is the effective focal length of the second lens L2, and f4 is the effective focal length of the fourth lens L4. When the above relationship is satisfied, the contribution of the refractive powers of the second lens element L2 and the fourth lens element L4 in the optical system 10 can be reasonably distributed, so that the difference between the refractive powers of the second lens element L2 and the fourth lens element L4 is reasonable and cannot be too large, but a better balance can be obtained, thereby preventing the refractive power from being too concentrated on one of the lens elements to cause the sensitivity of the lens element to be too large, further better preventing the generation of field curvature, and playing a role in improving the imaging quality. In some embodiments, the relationship satisfied by optical system 10 may be specifically 2.08, 2.13, 2.2, 2.45, 2.6, 2.83, 2.95, 3.15, 3.37, 3.45, 3.5, or 3.55.

Fno is less than or equal to 1.9; fno is the f-number of the optical system 10. When the above relation is satisfied, the characteristic of large aperture of the system can be ensured, the optical system 10 has enough light input quantity, the imaging is clearer, and high-quality imaging of low-brightness object space scenes such as night scenes, starry sky and the like can be realized.

R9/R10 is more than or equal to 0.4 and less than or equal to 1; r9 is a radius of curvature of the image-side surface S8 of the fourth lens L4 at the optical axis, and R10 is a radius of curvature of the object-side surface S9 of the fifth lens L5 at the optical axis. When the above relationship is satisfied, the surface shape between the image-side surface S8 of the fourth lens L4 and the object-side surface S9 of the fifth lens L5 can be reasonably configured, and the exit angle of the light on the image-side surface S8 of the fourth lens L4 and the incident angle on the object-side surface S9 of the fifth lens L5 can be reasonably reduced, so that the influence of the tolerance in the optical system 10 on the field of view can be reduced, that is, the tolerance sensitivity of the field of view can be reduced, and the yield of the system can be improved. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.47, 0.475, 0.48, 0.5, 0.54, 0.63, 0.68, 0.72, 0.75, 0.79, 0.8, 0.82, 0.823, or 0.83.

D4/CT5 is more than or equal to 0.5 and less than or equal to 2.0; d4 is the distance on the optical axis from the image-side surface S8 of the fourth lens element L4 to the object-side surface S9 of the fifth lens element L5, and CT5 is the thickness on the optical axis of the fifth lens element L5. When the relationship is satisfied, the ratio of the spacing distance between the fourth lens L4 and the fifth lens L5 to the thickness of the fifth lens L5 can be controlled in a reasonable range, so that the high-level aberration generated by the system can be effectively balanced, the field curvature adjustment in engineering manufacturing is facilitated, and the imaging quality of the system is improved. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.8, 0.86, 0.94, 1.14, 1.25, 1.38, 1.47, 1.56, 1.58, or 1.62.

F1/f is more than or equal to 0.8 and less than or equal to 1.0; f1 is the effective focal length of the first lens L1. When the above relationship is satisfied, the refractive power contribution of the first lens element L1 in the system can be reasonably distributed, on one hand, the first lens element L1 can better converge the light rays incident from the object space, so as to increase the field range of the optical system 10 and shorten the total length of the optical system 10, and on the other hand, the first lens element L1 can be prevented from generating too large aberration, so that the system has good imaging quality. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.81, 0.82, 0.83, 0.84, or 0.85.

TTL/f is more than or equal to 1.0 and less than or equal to 1.5; TTL is a distance from the object-side surface S1 of the first lens element L1 to the image plane S11 of the optical system 10 on the optical axis 101. When the above relationship is satisfied, it is possible to prevent an excessively large angle of view of the system while facilitating the reduction of the length of the optical system 10, and to balance the miniaturization of the optical system 10 and the reduction of aberrations in a large field of view. When the optical length is less than the lower limit of the above relationship, the optical length of the optical system 10 is too short, which may cause a problem of increasing the system sensitivity, resulting in difficulty in aberration correction; or the field angle of the system is too small to satisfy the large field characteristic. When the optical length is higher than the upper limit of the above relationship, the optical length of the optical system 10 is too long, which is disadvantageous for miniaturization design, and the light of the marginal field of view is difficult to image on the effective imaging area of the imaging plane, thereby causing incomplete imaging information. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.143, 1.145, 1.147, or 1.149.

1.3mm≤Imgh²V (TTL and Fno) is less than or equal to 2.0 mm; where "Imgh" is half of the image height corresponding to the maximum field angle of the optical system 10, "TTL" is the distance from the object-side surface S1 of the first lens element L1 to the image plane S11 of the optical system 10 on the optical axis 101, and "Fno" is the f-number of the optical system 10. When the image sensor is assembled, Imgh can also be understood as the distance from the center of the rectangular effective pixel area of the image sensor to the edge of the diagonal line. When the above relationship is satisfied, the maximum image height, the total optical length, and the f-number of the optical system 10 can be reasonably configured, so that not only the length of the system can be effectively compressed to realize a miniaturized design, but also the system can have a large image plane characteristic and a sufficient light input amount, thereby improving the imaging quality. In addition, when the above relationship is satisfied, it is also beneficial to further make the optical system 10 possess a large field of view characteristic to obtain more object space information.

The numerical reference wavelength for the focal length and the numerical reference wavelength for the refractive index and the abbe number in the above respective relational conditions are respectively 555nm and 587.56 nm. In addition, each of the above-mentioned focal length parameters at least represents a focal length value of the corresponding lens element at the paraxial region, and when describing the refractive power of the lens element, it also represents the refractive power of the corresponding lens element at the paraxial region.

The above relational conditions and the corresponding technical effects are directed to the five-piece optical system 10 having the above lens design. When the optical system 10 cannot be ensured to have the above lens design (number of lenses, refractive power arrangement, surface type arrangement, etc.), it is difficult to ensure that the system can still have the corresponding technical effect when the relation conditions are satisfied, and even the imaging performance may be significantly reduced.

The optical system 10 includes an aperture stop STO for controlling the amount of light entering the optical system 10 and at the same time, can function to block the ineffective light. When the projection of the aperture stop STO on the optical axis 101 overlaps the projection of the object-side surface S1 of the first lens L1 on the optical axis 101, the aperture stop STO can also be considered to be disposed on the object side of the first lens L1, and at least a part of the structure of the object-side surface S1 of the first lens L1 passes through the aperture stop STO toward the object side. The aperture stop STO may be provided on the object side of the first lens L1 or between the lenses. The aperture stop STO may be formed by a barrel structure holding a lens, may be formed by a gasket, or may be formed by a light-shielding coating on the surface of the lens.

In some embodiments, at least one of the lens surfaces of the first to fifth lenses L1 to L5 is aspheric, i.e., at least one of the first to fifth lenses L1 to L5 has an aspheric surface type. Specifically, the object-side surface and the image-side surface of the first lens L1 through the fifth lens L5 in some embodiments are aspheric. The aspheric surface can further help the optical system 10 to better eliminate aberration, and is also beneficial to 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 of the lens surfaces of the first lens L1 through the fifth lens L5 is a spherical surface. The spherical surface type can effectively reduce the processing difficulty of the lens and balance the preparation cost. It should be noted that the actual surface shape of the lens is not limited to the spherical or aspherical shape shown in the drawings, which are merely exemplary references and not drawn to scale. It should also be noted that when the object-side surface or the image-side surface of a lens is aspheric, the surface may be convex or concave as a whole, or the surface may be designed to have a point of inflection, where the surface shape of the surface changes from center to edge, for example, the surface is convex at the center and concave at the edge.

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.

On the other hand, in some embodiments, at least one lens of the optical system 10 is made of plastic. In particular, the material of each lens in the optical system 10 in some embodiments may be plastic. Of course, in some embodiments, the material of at least one lens in the optical system 10 may also be glass. For example, in some embodiments, each lens is made of glass. The plastic lens can reduce the weight of the optical system 10 and the production cost, while the glass lens can withstand higher temperatures and has excellent optical effects. The arrangement relationship of the lens materials in the optical system 10 is not limited to the above embodiments, and the material of any lens may be plastic or glass, and the specific material arrangement may be determined according to the actual design requirement.

In some embodiments, the optical system 10 includes an ir-cut filter 110, and the ir-cut filter 110 is disposed on the image side of the fifth lens L5 and is fixed relative to each lens in the optical system 10. The ir-cut filter 110 is used to filter the infrared light and prevent the infrared light from reaching the imaging surface S11 of the system, so as to prevent the infrared light from interfering with normal imaging. The infrared cut filter 110 may be assembled with each lens as part of the optical system 10. In other embodiments, the infrared cut filter 110 is not a component of the optical system 10, and the infrared cut filter 110 may be installed between the optical system 10 and the image sensor when the optical system 10 is assembled with the image sensor. In some embodiments, the infrared cut filter 110 may also be disposed on the object side of the first lens L1. In addition, in some embodiments, the function of filtering infrared light can also be achieved by providing a filter plating layer on at least one of the first lens L1 to the fifth lens L5.

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 and 2, in the first embodiment, the optical system 10 includes, in order from an object side to an image side along an optical axis 101, an aperture stop STO, a first lens element L1 with positive 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, and a fifth lens element L5 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, and the reference wavelengths of the astigmatism diagram and the distortion diagram in the following embodiments are all 555 nm.

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

The object-side surface S3 of the second lens element L2 is concave at the paraxial region thereof, and the image-side surface S4 is concave at the paraxial region thereof; the object side S3 is convex at the circumference, and the image side S4 is concave at the circumference.

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

The object-side surface S7 of the fourth lens element L4 is concave at the paraxial region thereof, and the image-side surface S8 is convex at the paraxial region thereof; object side S7 is concave at the circumference, and image side S8 is convex at the circumference.

The object-side surface S9 of the fifth lens element L5 is concave at the paraxial region thereof, and the image-side surface S10 is concave at the paraxial region thereof; object side S9 is concave at the circumference, and image side S10 is convex at the circumference.

The first lens element L1 to the fifth lens element L5 are all made of plastic, and the object-side surface and the image-side surface of each lens element are aspheric.

In the optical system 10, the first lens element L1 provides positive refractive power, which is favorable for obtaining object space information by a large aperture system to obtain a larger field of view and shorten the length of the system, and the second lens element L2 to the fifth lens element L5 are configured by the above-mentioned refractive power and surface shape to balance the aberration generated by the first lens element L1.

The lens parameters of the optical system 10 in this embodiment are given in tables 1 and 2 below. Table 2 presents the aspheric coefficients of the corresponding lens surfaces in table 1, where K is the conic coefficient and Ai is the coefficient corresponding to the ith order higher order term in the aspheric surface profile formula. The elements from the object side to the image side of the system are arranged in the order from top to bottom in table 1. The diaphragm in the table is the aperture diaphragm STO and the infrared filter is the infrared cut-off filter. Surfaces corresponding to surface numbers 2 and 3 respectively represent 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 is the radius of curvature of the corresponding surface of the lens at the optical axis. The absolute value of the first value of the lens in the thickness parameter list is the thickness of the lens on the optical axis, and the absolute value of the second value is the distance from the image side surface of the lens to the next optical element on the optical axis. In the parameter tables of the following respective examples (first to sixth examples), the numerical reference wavelength of the refractive index and the abbe number of each lens was 587.56nm, and the numerical reference wavelength of the focal length was 555nm, and the numerical units of the Y radius, the thickness, and the focal length (effective focal length) were all millimeters (mm). In addition, the relational expression calculation and the lens structure of each example are subject to the data provided in the parameter tables (e.g., table 1, table 2, table 3, table 4, etc.).

TABLE 1

As can be seen from table 1, the effective focal length f of the optical system 10 is 4.27mm, the f-number FNO is 1.89, the maximum field angle FOV is 81.1 °, and the total optical length TTL is 4.9 mm. 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 angle of view of the optical system 10 parallel to the diagonal direction.

TABLE 2

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

f12/f is 1.23; f12 is the combined focal length of the first lens L1 and the second lens L2, and f is the effective focal length of the optical system 10. When the five-piece optical system 10 with the above-mentioned refractive power and surface design further satisfies the relationship, it is able to reasonably control the refractive power strength of the front lens group composed of the first lens L1 and the second lens L2, so as to effectively balance the refractive power distribution of the front lens group in the whole optical system 10, thereby balancing the aberration generated by the rear lens group composed of the third lens L3 to the fifth lens L5, avoiding the difficulty in implementing correction of the rear lens group due to the larger aberration generated by the front lens group due to the too strong refractive power, and further improving the imaging quality of the system; meanwhile, the front lens group has enough positive refractive power to effectively converge the light incident from the object, thereby enlarging the field range of the optical system 10.

SAG41/CT4 is 0.64; SAG41 is the saggital height of the object side S7 of the fourth lens L4 at the maximum effective aperture, CT4 is the thickness of the fourth lens L4 on the optical axis. When the relation is met, the object side S7 surface shape and the lens thickness of the fourth lens L4 can be reasonably controlled, so that the fourth lens L4 can be driven to be not excessively bent on the whole structure, the processing and forming of the lenses are facilitated, the manufacturing sensitivity is reduced, and the engineering manufacturing is better realized; meanwhile, the surface shape of the fourth lens L4 is not too gentle, so that the fourth lens L4, which is one of the last two lenses of the system, can realize good adjustment on astigmatism of the marginal field of view.

CT3/ET3 ═ 1.28; CT3 is the thickness of the third lens element L3 along the optical axis, and ET3 is the distance from the maximum effective aperture of the third lens element L3 at the object side S5 to the maximum effective aperture of the image side S6 along the optical axis. When the relation is met, on one hand, the processing and molding of the third lens L3 are facilitated, and the assembly difficulty is reduced; on the other hand, the field curvature of the system can be effectively corrected, and the imaging quality of the system is improved.

27.6 | V4-V3 |; v3 is the abbe number of the third lens L3, and V4 is the abbe number of the fourth lens L4. When the above relation is satisfied, the abbe numbers of the third lens L3 and the fourth lens L4 can be controlled within a reasonable range, so that the aberration of the system can be improved, achromatization is facilitated, the secondary spectrum of the system is reduced, and the imaging performance of the system is improved.

TTL/Imgh is 1.32; TTL is the distance on the optical axis from the object-side surface S2 of the first lens element L1 to the image plane S11 of the optical system 10, and Imgh is half the image height corresponding to the maximum field angle of the optical system 10. When the above relationship is satisfied, on the one hand, the optical system 10 can have an ultra-thin characteristic, and the design requirement of system miniaturization can be realized; on the other hand, the optical system 10 can also be made to have a large image plane characteristic, thereby enabling matching with an image sensor of a higher pixel.

3.13, | f2/f4 |; f2 is the effective focal length of the second lens L2, and f4 is the effective focal length of the fourth lens L4. When the above relationship is satisfied, the contribution of the refractive powers of the second lens element L2 and the fourth lens element L4 in the optical system 10 can be distributed reasonably, so that the refractive powers of the two lens elements are not too large, and the generation of field curvature can be prevented well.

Fno 1.89; fno is the f-number of the optical system 10. When the above relation is satisfied, the characteristic of large aperture of the system can be ensured, the optical system 10 has enough light input quantity, the imaging is clearer, and high-quality imaging of low-brightness object space scenes such as night scenes, starry sky and the like can be realized.

R9/R10 ═ 0.48; r9 is a radius of curvature of the image-side surface S8 of the fourth lens L4 at the optical axis, and R10 is a radius of curvature of the object-side surface S9 of the fifth lens L5 at the optical axis. When the above relationship is satisfied, the surface shape between the image-side surface S8 of the fourth lens L4 and the object-side surface S9 of the fifth lens L5 can be reasonably configured, so that the exit angle of the light on the image-side surface S8 of the fourth lens L4 and the incident angle on the object-side surface S9 of the fifth lens L5 can be reasonably reduced, the influence of the tolerance in the optical system 10 on the field of view can be reduced, the tolerance sensitivity of the field of view can be reduced, and the yield of the system can be improved.

D4/CT5 is 0.85; d4 is the distance on the optical axis from the image-side surface S8 of the fourth lens element L4 to the object-side surface S9 of the fifth lens element L5, and CT5 is the thickness on the optical axis of the fifth lens element L5. When the relationship is satisfied, the ratio of the spacing distance between the fourth lens L4 and the fifth lens L5 to the thickness of the fifth lens L5 can be controlled in a reasonable range, so that the high-level aberration generated by the system can be effectively balanced, the field curvature adjustment in engineering manufacturing is facilitated, and the imaging quality of the system is improved.

f1/f is 0.82; f1 is the effective focal length of the first lens L1. When the above relationship is satisfied, the refractive power contribution of the first lens element L1 in the system can be reasonably distributed, on one hand, the first lens element L1 can better converge the light rays incident from the object space, so as to increase the field range of the optical system 10 and shorten the total length of the optical system 10, and on the other hand, the first lens element L1 can be prevented from generating too large aberration, so that the system has good imaging quality.

TTL/f is 1.15; TTL is a distance from the object-side surface S1 of the first lens element L1 to the image plane S11 of the optical system 10 on the optical axis 101. When the above relationship is satisfied, it is possible to prevent an excessively large angle of view of the system while facilitating the reduction of the length of the optical system 10, and to balance the miniaturization of the optical system 10 and the reduction of aberrations in a large field of view.

Imgh²(TTL × Fno) ═ 1.49 mm; imgh is half the image height corresponding to the maximum field angle of the optical system 10, TTL is the distance on the optical axis 101 from the object-side surface S1 of the first lens element L1 to the image plane S11 of the optical system 10,fno is the f-number of the optical system 10. When the image sensor is assembled, Imgh can also be understood as the distance from the center of the rectangular effective pixel area of the image sensor to the edge of the diagonal line. When the above relationship is satisfied, the maximum image height, the total optical length, and the f-number of the optical system 10 can be reasonably configured, so that not only the length of the system can be effectively compressed to realize a miniaturized design, but also the system can have a large image plane characteristic and a sufficient light input amount, thereby improving the imaging quality. In addition, when the above relationship is satisfied, it is also beneficial to further make the optical system 10 possess a large field of view characteristic to obtain more object space information.

In addition, fig. 2 includes a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the optical system 10, which shows the deviation of the convergent focal points of the light rays of different wavelengths after passing through the lens. The ordinate of the longitudinal spherical aberration diagram represents the Normalized Pupil coordinate (Normalized Pupil coordmator) from the Pupil center to the Pupil edge, and the abscissa represents the distance (in mm) of the imaging plane from the intersection point of the ray with the optical axis. It can be known from the longitudinal spherical aberration diagram that the convergent focus deviation degrees of the light rays with different wavelengths in the first embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed. FIG. 2 also includes a Field curvature map (adaptive Field Curves) of optical system 10, where the S curve represents sagittal Field curvature at 555nm and the T curve represents meridional Field curvature at 555 nm. As can be seen from the figure, the field curvature of the system is small, the field curvature and astigmatism of each field of view are well corrected, and the center and the edge of the field of view 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, the maximum Distortion is controlled within 2%, and the imaging quality of the system is excellent.

Second embodiment

Referring to fig. 3 and 4, in the second embodiment, the optical system 10 includes, in order from an object side to an image side along an optical axis 101, an aperture stop STO, a first lens element L1 with positive 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, and a fifth lens element L5 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 the second embodiment.

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 S3 is convex at the circumference, and the image side S4 is concave at the circumference.

The object-side surface S5 of the third lens element L3 is concave at the paraxial region thereof, and the image-side surface S6 is convex at the paraxial region thereof; object side S5 is concave at the circumference, and image side S6 is convex at the circumference.

The object-side surface S9 of the fifth lens element L5 is concave at the paraxial region thereof, and the image-side surface S10 is concave at the paraxial region thereof; the object side S9 is convex at the circumference, and the image side S10 is convex at the circumference.

In addition, 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 is not repeated herein.

TABLE 3

TABLE 4

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

f12/f	1.20	Fno	1.89
				SAG41/CT4	0.66	R9/R10	0.468
CT3/ET3	1.29	D4/CT5	0.78
				\|V4-V3\|	27.60	f1/f	0.81
TTL/Imgh	1.32	TTL/f	1.14
				\|f2/f4\|	3.26	Imgh²/(TTL*Fno)	1.49

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

Third embodiment

Referring to fig. 5 and 6, in the third embodiment, the optical system 10 includes, in order from an object side to an image side along the optical axis 101, an aperture stop STO, the first lens element L1 with positive refractive power, the second lens element L2 with negative refractive power, the third lens element L3 with negative refractive power, the fourth lens element L4 with positive refractive power, and the fifth lens element L5 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 the third embodiment.

In addition, the lens parameters of the optical system 10 in the third embodiment are given 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.

TABLE 5

TABLE 6

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

f12/f	1.18	Fno	1.89
				SAG41/CT4	0.56	R9/R10	0.506
CT3/ET3	1.24	D4/CT5	1.09
				\|V4-V3\|	27.60	f1/f	0.85
TTL/Imgh	1.32	TTL/f	1.15
				\|f2/f4\|	3.56	Imgh²/(TTL*Fno)	1.49

as can be seen from the aberration diagram in fig. 6, the longitudinal spherical aberration, curvature of field, and distortion of the optical system 10 are well controlled, so that the optical system 10 of this embodiment has good imaging quality.

Fourth embodiment

Referring to fig. 7 and 8, in the fourth embodiment, the optical system 10 includes, in order from an object side to an image side along an optical axis 101, an aperture stop STO, a first lens element L1 with positive 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, and a fifth lens element L5 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 the fourth embodiment.

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

In addition, the lens parameters of the optical system 10 in the fourth embodiment are given 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.

TABLE 7

TABLE 8

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

f12/f	1.19	Fno	1.89
				SAG41/CT4	0.61	R9/R10	0.476
CT3/ET3	1.24	D4/CT5	0.92
				\|V4-V3\|	27.60	f1/f	0.83
TTL/Imgh	1.32	TTL/f	1.15
				\|f2/f4\|	3.50	Imgh²/(TTL*Fno)	1.49

as can be seen from the aberration diagram in fig. 8, the longitudinal spherical aberration, curvature of field, and distortion of the optical system 10 are well controlled, so that the optical system 10 of this embodiment has better imaging quality.

Fifth embodiment

Referring to fig. 9 and 10, in the fifth embodiment, the optical system 10 includes, in order from an object side to an image side along an optical axis 101, an aperture stop STO, a first lens element L1 with positive 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, and a fifth lens element L5 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 the fifth embodiment.

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; object side S7 is concave at the circumference, and image side S8 is convex at the circumference.

In addition, the lens parameters of the optical system 10 in the fifth embodiment are given in tables 9 and 10, wherein the definitions of the structures and parameters can be obtained from the first embodiment, which are not repeated herein.

TABLE 9

Watch 10

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

as can be seen from the aberration diagram in fig. 10, the longitudinal spherical aberration, curvature of field, and distortion of the optical system 10 are well controlled, so that the optical system 10 of this embodiment has good imaging quality.

Sixth embodiment

Referring to fig. 11 and 12, in the sixth embodiment, the optical system 10 includes, in order from an object side to an image side along an optical axis 101, an aperture stop STO, the first lens element L1 with positive 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, and the fifth lens element L5 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 the sixth embodiment.

In addition, 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 repeated herein.

TABLE 11

TABLE 12

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

f12/f	1.23	Fno	1.88
				SAG41/CT4	0.62	R9/R10	0.835
CT3/ET3	1.34	D4/CT5	1.63
				\|V4-V3\|	27.60	f1/f	0.83
TTL/Imgh	1.32	TTL/f	1.14
				\|f2/f4\|	2.06	Imgh²/(TTL*Fno)	1.49

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

The optical system 10 in the first to sixth embodiments can make the system have characteristics of a large image plane and a large aperture by reasonably combining and designing the characteristics of the refractive power, the structure, the parameter relationship and the like of the lens, so that the optical system can realize the imaging effect of high pixel and high resolution, and can also meet the requirement of clear imaging in a dark environment.

Referring to fig. 13, some embodiments of the present disclosure further provide a camera module 20, where the camera module 20 may include 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) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor. Generally, the imaging surface S11 of the optical system 10 overlaps the photosensitive surface of the image sensor 210 when assembled.

The optical system 10 in the present application can realize good correction of aberrations, and therefore, by adopting the optical system 10, the imaging quality of the camera module 20 can be improved.

Referring to fig. 14, some embodiments of the present application also provide an electronic device 30. 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 display screen, a circuit board, a middle frame, a rear cover, or the like. The electronic device 30 may be, but is not limited to, a smart phone, a smart watch, smart glasses, an electronic book reader, a vehicle-mounted camera, a monitoring device, an unmanned aerial vehicle, a medical device (such as an endoscope), a tablet computer, a biometric device (such as a fingerprint recognition device or a pupil recognition device), a PDA (Personal Digital Assistant), an unmanned aerial vehicle, and the like. By adopting the camera module 20, the electronic device 30 can have good shooting performance.

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 third lens element with refractive power;

a fourth lens element with refractive power;

the optical system satisfies the relationship:

1.0≤f12/f≤1.25；

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

0.4≤SAG41/CT4≤1.0；

SAG41 is the sagittal height of the object side of the fourth lens at the maximum effective aperture, and CT4 is the thickness of the fourth lens on the optical axis.

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

1.0≤CT3/ET3≤1.5；

CT3 is the thickness of the third lens element along the optical axis, and ET3 is the distance from the maximum effective aperture at the object side to the maximum effective aperture at the image side along the optical axis of the third lens element.

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

2≤|f2/f4|≤4；

f2 is the effective focal length of the second lens, and f4 is the effective focal length of the fourth lens.

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

0.4≤R9/R10≤1；

r9 is a radius of curvature of an image-side surface of the fourth lens element at an optical axis, and R10 is a radius of curvature of an object-side surface of the fifth lens element at the optical axis.

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

0.5≤D4/CT5≤2.0；

d4 is an axial distance between an image-side surface of the fourth lens element and an object-side surface of the fifth lens element, and CT5 is an axial thickness of the fifth lens element.

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

0.8≤f1/f≤1.0；

f1 is the effective focal length of the first lens.

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

1.0≤TTL/f≤1.5；

TTL is a distance on the optical axis from the object-side surface of the first lens element to the imaging surface of the optical system.

9. A camera module comprising an image sensor and the optical system of any one of claims 1 to 8, wherein the image sensor is disposed on an image side of the optical system.

10. An electronic device, comprising a fixing member and the camera module set according to claim 9, wherein the camera module set is disposed on the fixing member.