CN112904541A

CN112904541A - Optical system, camera module and electronic equipment

Info

Publication number: CN112904541A
Application number: CN202110200886.4A
Authority: CN
Inventors: 华露; 杨健; 李明
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2021-02-23
Filing date: 2021-02-23
Publication date: 2021-06-04
Anticipated expiration: 2041-02-23
Also published as: CN112904541B

Abstract

The invention relates to an optical system, a camera module and an electronic device. The optical system includes in order from an object side to an image side: 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 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; a fifth lens element having a convex image-side surface at a paraxial region; a sixth lens element having a concave image-side surface at a paraxial region; a seventh lens element having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region, both of which are aspheric, and at least one of which has an inflection point; the optical system further satisfies: f/TTL is more than 1.004 and less than 1.1; f is the effective focal length of the optical system, and TTL is the total optical length of the optical system. The optical system has miniaturization and long-focus characteristics.

Description

Optical system, camera module and electronic equipment

Technical Field

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

Background

In recent years, the updating period of mobile phones is shorter and shorter, the shooting function is stronger and stronger, and the market requirements on a single type of lens are stricter and stricter. With the diversified requirements of consumers on the shooting environments, the types of the lenses suitable for different shooting environments are increasing. The telephoto lens has a longer focal length, so that a shallower depth of field can be obtained, and further, the far scene details can be better processed, and the imaging effect of compressing the shooting distance is achieved.

However, the conventional telephoto lens tends to have problems of an excessive size and insufficient processing power for details of a distant view.

Disclosure of Invention

In view of the above, it is necessary to provide an optical system, an image pickup module, and an electronic apparatus for solving the problem of how to compress the length of a telephoto lens and better handle the details of a perspective.

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 and a concave image-side surface;

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

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

a fourth lens element with refractive power;

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

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

a seventh lens element with refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region, both the object-side surface and the image-side surface being aspheric, and at least one of the object-side surface and the image-side surface having an inflection point;

the optical system also satisfies the relationship:

f/TTL is more than 1.004 and less than 1.1; and

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

In the optical system, the refractive power and the surface type configuration of the first lens element are beneficial to increasing the light incoming brightness of the optical system and improving the imaging definition, and on the other hand, the refractive power and the surface type configuration of the first lens element are also beneficial to increasing the field angle of the optical system and widening the shooting range; the front lens and the rear lens of the second lens have positive refractive power, and the total length of the system can be favorably shortened and the system can be promoted to reach aberration balance by enabling the second lens to have the refractive power and the surface shape setting; the surface design of the third lens is favorable for enhancing the strength of positive refractive power, so that the aberration generated by the object lens is favorably corrected; the fifth lens can also correct astigmatic aberration, distortion and other aberrations generated by the object lens; the design of the sixth lens is beneficial to shortening the total length of the system; the seventh lens is in face design, so that on one hand, the optical system can obtain a larger image plane to match with an image sensor with higher pixels, and on the other hand, the back focus of the optical system can be increased, and therefore the optical system is enabled to have enough safety distance in the module assembling process to avoid collision. On the other hand, the optical system can be advantageous to have a telephoto characteristic by the above number of lenses, refractive power arrangement, and surface type design, and on the other hand, aberrations generated between the lenses can be well balanced, thereby suppressing the overall aberrations of the optical system and making the imaging effect more excellent.

In addition, the optical system can obtain a longer focal length to have a long-focus characteristic by satisfying the relation that f/TTL is less than 1.004 and less than 1.1, and the total length of the optical system can be compressed to enable the optical system to have a relatively compact structure, so that the miniaturization design of the optical system is realized. In addition, when the relation is met, the optical system is facilitated to better process the details of the far scene, so that the details of the focused far scene are more prominent, a good telephoto imaging effect is achieved, and a user obtains better shooting experience.

In one embodiment, the optical system satisfies the relationship:

1.09＜2*Imgh/TTL＜1.2；

imgh is half the image height corresponding to the maximum field angle of the optical system. The optical system with the refractive power and the surface design further satisfies the relation condition, on one hand, the optical system can be favorable for further realizing a long-focus shooting effect, and on the other hand, the optical system can have a larger image surface size under the condition of maintaining miniaturization, so that the optical system is favorable for having large image surface characteristics, and further can better present the shooting details of a long shot, and the long shot shooting performance of the optical system is improved.

In one embodiment, the optical system satisfies the relationship:

1＜f123/R12＜1.8；

f123 is a combined focal length of the first lens element, the second lens element and the third lens element, and R12 is a radius of curvature of the image-side surface of the first lens element at the optical axis. When the relation is met, the combined effective focal length of the first lens, the second lens and the third lens and the curvature radius of the image side surface of the first lens can be reasonably configured, on one hand, the positive refractive power strength of a lens group formed by the first three lenses in the optical system can be reasonably controlled, and the image side surface shape of the first lens is matched, so that incident light can be well regulated and controlled when entering the optical system, the air gap between every two adjacent lenses in the optical system can be effectively reduced, and the total length of the system can be further reduced; on the other hand, the image side surface type of the first lens is controlled, so that the aberration generated by the image side lens can be balanced. If the upper limit of the above relationship range is exceeded, the curvature radius of the image-side surface of the first lens element is too small, which causes the gap between the surface-side surface and the second lens element to be too small due to excessive bending, which not only increases the difficulty of processing and molding the lens elements, but also causes difficulty in assembling the lens elements, and also tends to cause excessive concentration of refractive power on the first lens element, thereby increasing the tolerance sensitivity of the first lens element. If the value is less than the lower limit of the above relationship range, the curvature radius of the image-side surface of the first lens is too large, and the surface shape is too gentle, which is disadvantageous in correcting spherical aberration, coma aberration, and astigmatism generated in the two lenses.

In one embodiment, the optical system satisfies the relationship:

-2.2＜f567/f＜-0.9；

f567 is a combined focal length of the fifth lens, the sixth lens and the seventh lens. When the relationship is satisfied, the ratio of the combined focal length of the fifth lens element, the sixth lens element and the seventh lens element to the total effective focal length of the optical system is controlled within a reasonable range, so as to balance spherical aberration and chromatic aberration generated by the object side lens element, and the combined refractive power strength of the fifth lens element and the seventh lens element can be reasonably adjusted, so that the refractive power strength of the optical system is effectively prevented from being excessively concentrated on the rear lens group, and the aberration correction capability of the system can be better improved. Meanwhile, the length of the optical system can be effectively reduced when the relation is satisfied, and the long-focus characteristic of the optical system is highlighted. When the upper limit of the relationship is exceeded, the negative refractive power provided by the rear lens group formed by the fifth lens element, the sixth lens element and the seventh lens element is too large, so that the refractive power of the optical system is excessively concentrated in the rear lens group, and the aberration correction capability of the system is reduced. When the refractive power is lower than the lower limit of the above relationship, the negative refractive power provided by the rear lens group formed by the fifth lens element, the sixth lens element and the seventh lens element is insufficient to balance the positive refractive power of the front lens group, which is not favorable for the telephoto characteristic and the large image plane characteristic.

In one embodiment, the optical system satisfies the relationship:

1＜f/f3＜1.6；

f3 is the effective focal length of the third lens. When the relation is satisfied, the total effective focal length of the optical system and the effective focal length of the third lens can be reasonably configured, so that the surface type of the third lens is appropriate, the incident angle of light rays on the lens is favorably reduced, the tolerance sensitivity of the third lens is reduced, and the optical system is favorably provided with a long-focus characteristic. When the refractive power is higher than the upper limit of the above relationship, the positive refractive power contributed by the third lens element is too strong to form aberration balance with the front and rear lens groups, thereby affecting the imaging quality. When the refractive power of the third lens element is lower than the lower limit of the above relationship, the positive refractive power of the third lens element is insufficient, and the aberration generated by the front and rear lens groups is difficult to be sufficiently corrected, resulting in a reduction in image quality.

In one embodiment, the optical system satisfies the relationship:

2.5＜ct56/et56＜7；

ct56 is the distance on the optical axis from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element, and et56 is the distance in the optical axis direction from the maximum effective aperture on the image-side surface of the fifth lens element to the maximum effective aperture on the object-side surface of the sixth lens element. When the relation is met, the distance between the fifth lens and the sixth lens on the optical axis and the distance between the fifth lens and the sixth lens at the position of the maximum effective diameter can be reasonably configured, so that on one hand, the light deflection angle between the fifth lens and the sixth lens is favorably reduced, and the tolerance sensitivity of the two lenses can be further reduced; on the other hand, the assembly between the fifth lens and the sixth lens is also facilitated; in addition, it is also helpful to reduce the size of the rear end of the optical system. Above the upper limit of the above relationship, the edge gap between the fifth lens and the sixth lens is too small, and the two lens edges are too close, increasing the risk of poor assembly.

In one embodiment, the optical system satisfies the relationship:

0.4＜|sag61|/et6＜1.1；

sag61 is the rise of the object-side surface of the sixth lens at the maximum effective aperture, and et6 is the thickness of the sixth lens from the maximum effective aperture at the object-side surface to the maximum effective aperture at the image-side surface in the optical axis direction. When the relation is met, the ratio of the rise of the object-side surface of the sixth lens at the maximum effective diameter to the thickness of the edge of the sixth lens can be reasonably configured, on one hand, the inclination angle of the object-side surface of the sixth lens at the edge is favorably controlled, so that the surface type of the surface from the center to the edge can be smoothly transited, and the edge light rays can be transited to the next lens to an imaging surface at a relatively slow angle; on the other hand, the edge thickness of the sixth lens can be controlled within a reasonable range, so that the thickness ratio of the whole lens is favorably controlled, the thickness ratio is not too large or too small, and the difficulty in molding and assembling the lens is reduced. When the height is higher than the upper limit of the above relationship, the object-side surface of the sixth lens element is too curved to facilitate molding and assembling. When the light intensity is lower than the lower limit of the above relationship, the light intensity of the edge light is not favorably and smoothly transited when passing through the sixth lens, so that the edge part of the imaging surface has insufficient illumination intensity, and the imaging quality is reduced.

In one embodiment, the optical system satisfies the relationship:

-3＜sag71/et7＜-1；

sag71 is the rise of the object-side surface of the seventh lens at the maximum effective aperture, and et7 is the thickness of the seventh lens from the maximum effective aperture at the object-side surface to the maximum effective aperture at the image-side surface in the optical axis direction. When the relation is satisfied, the ratio of the object side surface of the seventh lens between the rise of the maximum effective diameter and the edge thickness is controlled within a reasonable range, so that the field angle of the seventh lens at the edge of the lens can be effectively controlled, incident light can enter the seventh lens at a small incident angle, and the incident light smoothly passes through the seventh lens to reach an imaging surface, thereby being beneficial to realizing the large image surface characteristic of an optical system and further remarkably improving the imaging quality. When the optical axis is lower than the lower limit of the relation, the object-side surface of the seventh lens is easy to be too steep, so that the reverse curvature is easy to generate, and the risk of generating ghost images is increased; when higher than the upper limit of the above relationship, the edge thickness of the seventh lens is excessively large, easily making the thickness ratio of the seventh lens excessively large, resulting in difficulty in lens molding.

In one embodiment, the optical system satisfies the relationship:

14＜f1/CT1＜23.5；

f1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens on the optical axis. When the relationship is satisfied, the refractive power strength and the center thickness of the first lens element can be well matched, so that the optical aberration of the optical system can be corrected, and the feasibility of the lens forming processing can be improved.

A camera module comprises an image sensor and any one of the optical systems, wherein the image sensor is arranged on the image side of the optical system. By adopting the optical system, the camera module has a long-focus characteristic, so that long-range details can be better processed, and excellent telephoto performance is achieved; the length of the camera module can also be compressed to realize miniaturization design.

An electronic device comprises a fixing piece and the camera module, wherein the camera module is arranged on the fixing piece. Electronic equipment can make a video recording the module with the space assembly of littleer, can also be through making a video recording the module in order to obtain good long-range scene shooting effect simultaneously.

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 structural diagram of an optical system according to a seventh embodiment of the present application;

FIG. 14 includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the seventh embodiment;

fig. 15 is a schematic structural diagram of an optical system according to an eighth embodiment of the present application;

FIG. 16 includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the eighth embodiment;

fig. 17 is a schematic view of a camera module according to an embodiment of the present application;

fig. 18 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "transverse," "length," "thickness," "upper," "front," "rear," "axial," "radial," and the like are used in the orientations and positional relationships indicated in the drawings for the purpose of convenience and simplicity of 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 are therefore not to be considered limiting.

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," "secured," and the like are to be construed broadly and can, 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 meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

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 with a seven-piece structure, where 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, a fifth lens L5, a sixth lens L6, and a seventh lens L7. 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. The above-described optical elements in the optical system 10 and a diaphragm, which is not mentioned temporarily, 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, the fifth lens L5 includes an object side surface S9 and an image side surface S10, the sixth lens L6 includes an object side surface S11 and an image side surface S12, and the seventh lens L539 7 includes an object side surface S13 and an image side surface S14. In addition, the optical system 10 further has an image forming surface S15, and the image forming surface S15 is located on the image side of the seventh lens L7. Generally, the image forming surface S15 of the optical system 10 coincides with the photosensitive surface of the image sensor, and for the sake of understanding, the image forming surface S15 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 convex object-side surface S3 at paraxial region and a concave image-side surface S4 at paraxial region; the third lens element L3 with positive refractive power has a convex object-side surface S5 at paraxial region; the fourth lens element L4 with positive or negative refractive power; the fifth lens element L5 with positive or negative refractive power has a convex image-side surface S10 at paraxial region; the sixth lens element L6 with positive or negative refractive power has a concave image-side surface S12 at paraxial region; the seventh lens element L7 with positive or negative refractive power has a convex object-side surface S13 at a paraxial region, a concave image-side surface S14 at a paraxial region, and both object-side surface S13 and image-side surface S14 being aspheric, and at least one of the object-side surface S13 and the image-side surface S14 having a point of inflection.

In the optical system 10, the refractive power and the surface type arrangement of the first lens element L1 are advantageous for increasing the light entering brightness of the optical system and improving the image clarity, and are also advantageous for increasing the field angle of the optical system and widening the shooting range; the front and rear lens elements of the second lens element L2 have positive refractive power, and the total length of the system can be advantageously shortened and the system can be made to achieve aberration balance by making the second lens element L2 have the above-mentioned refractive power and surface shape setting; the surface design of the third lens element L3 is favorable for enhancing the strength of the positive refractive power, so as to be favorable for correcting the aberration generated by the objective lens; the fifth lens L5 can also correct the aberrations such as astigmatism and distortion generated by the objective lens; the design of the sixth lens L6 is beneficial to shortening the total length of the system; the seventh lens L7, by having the above-mentioned surface design, is beneficial to the optical system 10 to obtain a larger image surface to match the image sensor with higher pixels on the one hand, and can also increase the back focus of the optical system 10 on the other hand, thereby promoting the optical system 10 to have enough safety distance to avoid collision during the module assembling process. On the other hand, the optical system 10 in the embodiment of the present application, through the above lens number, refractive power configuration and surface design, on one hand, is favorable for having a telephoto characteristic, and on the other hand, the aberration generated between the lenses can be well balanced, so that the overall aberration of the optical system 10 is suppressed, and the imaging effect is more excellent.

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 near 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 (at the optical axis 101) to the peripheral 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 definition of the relief features in this application is only for the surface type of the effective light transmission area of the respective lens surface.

In an embodiment of the present application, the optical system 10 further satisfies the following relationship:

f/TTL is more than 1.004 and less than 1.1; f is the effective focal length of the optical system 10, and TTL is the distance on the optical axis from the object-side surface S1 of the first lens element L1 to the image plane S15 of the optical system 10. TTL is also referred to as the total optical length of optical system 10.

When the above-mentioned relation conditions are satisfied, it is also advantageous for the optical system 10 to obtain a longer focal length to obtain a telephoto characteristic, and it is also advantageous for the total length of the optical system 10 to be compressed to make the optical system 10 have a relatively compact structure, thereby realizing a miniaturized design of the optical system 10. In addition, when the relationship is satisfied, the optical system 10 is also beneficial to better processing the details of the far scene, so that the details of the focused far scene are more prominent, a good telephoto imaging effect is achieved, and a user obtains better shooting experience. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.01, 1.015, 1.02, 1.025, 1.045, 1.065, 1.078, 1.083, 1.086, or 1.09.

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:

1.09 < 2 × Imgh/TTL < 1.2; imgh is half the image height corresponding to the maximum field angle of the optical system 10. Imgh can also be understood as the diagonal length of the rectangular effective imaging area on the imaging plane S15. When the image sensor is assembled, Imgh can also be understood as the distance from the center to the diagonal edge of the rectangular effective pixel area of the image sensor, and the diagonal direction of the effective imaging area is parallel to the diagonal direction of the rectangular effective pixel area. By further satisfying the relational expression condition, on the one hand, the optical system 10 can further realize a telephoto imaging effect, and on the other hand, the optical system 10 can have a large image plane size under the condition of maintaining miniaturization, thereby contributing to having a large image plane characteristic, and further being capable of better presenting the imaging details of a long shot, so as to improve the long shot performance of the optical system 10. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.095, 1.1, 1.11, 1.124, 1.136, 1.149, 1.158, 1.162, or 1.165.

F123/R12 is more than 1 and less than 1.8; f123 is a combined focal length of the first lens L1, the second lens L2, and the third lens L3, and R12 is a curvature radius of the image-side surface S2 of the first lens L1 at the optical axis. When the relationship is satisfied, the combined effective focal length of the first lens element L1, the second lens element L2 and the third lens element L3 and the curvature radius of the image-side surface S2 of the first lens element L1 can be reasonably configured, so that on one hand, the positive refractive power strength of the lens group formed by the first three lens elements in the optical system 10 can be reasonably controlled, and the image-side surface S2 profile of the first lens element L1 is matched, so that incident light can be well regulated and controlled when entering the optical system 10, and therefore, the air gaps between each adjacent lens element in the optical system 10 can be effectively reduced, and the total length of the system can be further reduced; on the other hand, it is also helpful to control the shape of the image side surface S2 of the first lens L1, so that the aberrations generated by the image side lens can be balanced. If the upper limit of the above relationship range is exceeded, the radius of curvature of the image-side surface S2 of the first lens element L1 is too small, and the gap between the surface-shaped object and the second lens element L2 is too small due to excessive bending, which not only increases the difficulty in processing and molding the lens elements, but also makes assembly between the lens elements difficult, and also tends to cause excessive concentration of refractive power in the first lens element L1, thereby increasing the tolerance sensitivity of the first lens element L1. If the value is less than the lower limit of the above relationship range, the curvature radius of the image side surface S2 of the first lens L1 is too large, and the surface shape is too gentle, which is disadvantageous in correcting spherical aberration, coma aberration, and astigmatism generated in the two lenses after correction. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.1, 1.13, 1.18, 1.25, 1.34, 1.43, 1.47, or 1.56.

-2.2 < f567/f < -0.9; f567 is a combined focal length of the fifth lens L5, the sixth lens L6, and the seventh lens L7. When the relationship is satisfied, the ratio of the combined focal length of the fifth lens element L5, the sixth lens element L6, and the seventh lens element L7 to the total effective focal length of the optical system 10 is controlled within a reasonable range, so as to balance spherical aberration and chromatic aberration generated by the object side lens element, and by reasonably adjusting the combined refractive power strength of the fifth lens element L5 through the seventh lens element L7, the refractive power strength of the optical system 10 is effectively prevented from being excessively concentrated on the rear lens group, so that the aberration correction capability of the system can be better improved. Meanwhile, satisfying this relationship also effectively reduces the length of the optical system 10 while emphasizing the telephoto characteristic of the optical system 10. When the upper limit of the above relationship is exceeded, the negative refractive power provided by the rear lens group formed by the fifth lens element L5, the sixth lens element L6 and the seventh lens element L7 is too large, so that the refractive power of the optical system 10 is excessively concentrated in the rear lens group, thereby reducing the system aberration correction capability. When the refractive power is lower than the lower limit of the above relationship, the negative refractive power provided by the rear lens group composed of the fifth lens element L5, the sixth lens element L6 and the seventh lens element L7 is insufficient to balance the positive refractive power of the front lens group, which is not favorable for telephoto characteristics and large image plane characteristics. In some embodiments, the relationship that optical system 10 satisfies may be specifically-2, -1.92, -1.85, -1.74, -1.53, -1.38, -1.2, -1.15, -1, or-0.95.

F/f3 is more than 1 and less than 1.6; f3 is the effective focal length of the third lens L3. When the relationship is satisfied, the total effective focal length of the optical system 10 and the effective focal length of the third lens L3 can be reasonably configured, so that the surface shape of the third lens L3 is suitable, which not only helps to reduce the incident angle of light rays on the lens and reduce the tolerance sensitivity of the third lens L3, but also is beneficial to the optical system 10 to have a telephoto characteristic. Above the upper limit of the above relationship, the positive refractive power of the third lens element L3 is too strong to balance the aberration of the front and rear lens elements, and thus the image quality is affected. When the lower limit of the above relationship is exceeded, the positive refractive power of the third lens element L3 is insufficient, and it is difficult to sufficiently correct aberrations generated in the front and rear lens groups, resulting in a reduction in image quality. In some embodiments, the relationship satisfied by optical system 10 may be specifically 1.1, 1.14, 1.18, 1.26, 1.34, 1.46, 1.49, 1.53, or 1.57.

2.5 < ct56/et56 < 7; ct56 is the distance on the optical axis from the image-side surface S10 of the fifth lens L5 to the object-side surface S11 of the sixth lens L6, and et56 is the distance on the optical axis from the maximum effective aperture of the image-side surface S10 of the fifth lens L5 to the maximum effective aperture of the object-side surface S11 of the sixth lens L6. When the relationship is satisfied, the distance between the fifth lens L5 and the sixth lens L6 on the optical axis and the distance between the fifth lens L5 and the sixth lens L6 at the maximum effective diameter can be reasonably configured, so that the light deflection angle between the fifth lens L5 and the sixth lens L6 can be reduced, and the tolerance sensitivity of the two lenses can be reduced; on the other hand, the assembly between the fifth lens L5 and the sixth lens L6 is also facilitated; in addition, it also helps to reduce the size of the rear end of the optical system 10. Above the upper limit of the above relationship, the edge gap between the fifth lens L5 and the sixth lens L6 is too small, and the two lens edges are too close to each other, increasing the risk of poor assembly. In some embodiments, the relationship satisfied by optical system 10 may be specifically 3, 3.3, 3.8, 4.5, 5.2, 5.8, 6, 6.35, or 6.5.

0.4 < | sag61|/et6 < 1.1; sag61 is the rise of the object-side surface S11 of the sixth lens L6 at the maximum effective aperture, and et6 is the thickness from the object-side surface S11 of the sixth lens L6 at the maximum effective aperture to the image-side surface S12 at the maximum effective aperture in the optical axis direction. It should be noted that the rise of a lens surface at the maximum effective aperture is the distance from the intersection of the surface with the optical axis 101 to the maximum effective aperture in a direction parallel to the optical axis 101. When the above relationship is satisfied, the ratio between the rise of the object-side surface S11 of the sixth lens L6 at the maximum effective diameter and the thickness of the edge of the sixth lens L6 can be reasonably configured, which is helpful to control the inclination angle of the object-side surface S11 of the sixth lens L6 at the edge, so that the surface profile of the surface from the center to the edge can be smoothly transited, and the edge light rays can also be transited to the subsequent lens to the image plane S15 at a relatively slow angle; on the other hand, the edge thickness of the sixth lens L6 can be controlled within a reasonable range, which is beneficial to controlling the thickness ratio of the whole lens so as not to be too large or too small, thereby reducing the difficulty of molding and assembling the lens. If the upper limit of the above relationship is exceeded, the object-side surface S11 of the sixth lens L6 is too curved to facilitate molding and assembling. When the lower limit of the above relationship is lower, it is not favorable for the edge light to smoothly transit when passing through the sixth lens L6, so that the edge portion of the imaging surface S15 does not have sufficient illuminance, and the imaging quality is degraded. In some embodiments, the relationship satisfied by optical system 10 may be specifically 0.5, 0.56, 0.64, 0.72, 0.81, 0.89, 0.94, 0.97, or 1.

-3 < sag71/et7 < -1; sag71 is the sagittal height of the object-side surface S13 of the seventh lens L7 at the maximum effective aperture, and et7 is the thickness from the object-side surface S13 of the seventh lens L7 at the maximum effective aperture to the image-side surface S14 at the maximum effective aperture in the optical axis direction. It should be noted that the rise of a lens surface at the maximum effective aperture is the distance from the intersection of the surface with the optical axis 101 to the maximum effective aperture in a direction parallel to the optical axis 101. When the value of sag71 is negative, it indicates that the maximum effective aperture position of the object side S13 of the seventh lens L7 is closer to the object side than the intersection position of the surface with the optical axis 101. When the above relationship is satisfied, the ratio of the rise of the object-side surface S13 of the seventh lens L7 at the maximum effective diameter to the edge thickness is controlled within a reasonable range, so that the opening angle of the seventh lens at the edge of the lens can be effectively controlled, incident light can enter the seventh lens L7 at a small incident angle and smoothly pass through the seventh lens L7 to reach the imaging surface S15, thereby facilitating the optical system 10 to realize large image plane characteristics, and further significantly improving the imaging quality. When the value is lower than the lower limit of the above relationship, the object-side surface S13 of the seventh lens L7 is likely to be excessively steep, so that the reverse curvature is likely to occur, and the risk of ghost image generation increases; when higher than the upper limit of the above relationship, the edge thickness of the seventh lens L7 is excessively large, easily making the thickness ratio of the seventh lens L7 excessively large, resulting in difficulty in lens molding. In some embodiments, the relationship that optical system 10 satisfies may be specifically-2.4, -2.2, -2, -1.84, -1.67, -1.55, -1.32, -1.26, or-1.2.

14 < f1/CT1 < 23.5; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 on the optical axis. When this relationship is satisfied, the refractive power strength and the center thickness of the first lens element L1 can be well matched, so that the optical aberration of the optical system 10 can be corrected and the feasibility of the lens forming process can be improved. In some embodiments, the relationship satisfied by optical system 10 may be specifically 14.5, 15.3, 15.8, 16.7, 18.2, 19.5, 20.7, 21.6, 22.5, or 23.

The reference wavelength of the parameters related to the focal length in the above relational conditions is 555nm, and the reference wavelengths of the parameters related to the refractive index and the abbe number are 587.6nm, that is, the wavelength of d light. In addition, each of the above focal length parameters at least represents the focal length of the corresponding lens at the paraxial region.

The above relational conditions and the technical effects thereof are directed to the seven-piece optical system 10 having the above-described 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 when the relationship 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 incoming light of the optical system 10 and at the same time can function to block non-effective light. The aperture stop STO may be provided on the object side of the first lens L1, or may be provided between two adjacent lenses of the first lens L1 to the seventh lens L7. The aperture stop STO may be formed of a barrel structure that sandwiches the lens, or may be a gasket separately fitted between the lens and the barrel.

In some embodiments, the object-side surface and/or the image-side surface of at least one of the first lens L1-the seventh lens L7 is aspheric, i.e., at least one of the first lens L1-the seventh lens L7 has an aspheric surface. For example, the object-side surface and the image-side surface of the first lens element L1 through the seventh lens element L7 may be aspheric. The aspheric surface can further help the optical system 10 to 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, the object-side surface and/or the image-side surface of at least one of the first lens L1 through the seventh lens L7 may also be spherical. 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 a convex surface as a whole or a concave surface as a whole. In some embodiments, the surface may also be designed to have a point of inflection where the surface profile of the surface changes from center to edge, e.g., the surface is convex near the optical axis and concave near the circumference.

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, the material of each lens in the optical system 10 is plastic. Of course, in some embodiments, the lens may be 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. In some embodiments, at least one of the first lens L1-the seventh lens L7 is made of plastic, and at least one is made of glass. The configuration 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 design may be determined according to actual requirements. In some embodiments, the plastic material may be polycarbonate.

In some embodiments, the optical system 10 further includes an infrared cut filter 110, and the infrared cut filter 110 is disposed on the image side of the seventh lens L7 and is fixedly disposed opposite 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 S15 of the optical system 10, 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 filtering plating layer on at least one of the first lens L1 to the seventh lens L7.

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, 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, an aperture stop STO, a fourth lens element L4 with negative refractive power, a fifth lens element L5 with negative refractive power, a sixth lens element L6 with negative refractive power, and a seventh lens element L7 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 surface S1 is convex at the near circumference, and the image-side surface S2 is concave at the near circumference.

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 S3 is convex near the circumference, and the image-side surface S4 is convex near 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 concave at the paraxial region; the object-side surface S5 is convex at the near circumference, and the image-side surface S6 is concave at the near 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; the object side S7 is concave near the circumference and the image side S8 is convex near 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 convex at the paraxial region thereof; object side S9 is concave near the circumference, and image side S10 is concave near the circumference.

The object-side surface S11 of the sixth lens element L6 is convex at the paraxial region, and the image-side surface S12 is concave at the paraxial region; object side S11 is concave near the circumference, and image side S12 is concave near the circumference.

The object-side surface S13 of the seventh lens element L7 is convex at the paraxial region, and the image-side surface S14 is concave at the paraxial region; the object-side surface S13 is convex at the near circumference, and the image-side surface S14 is concave at the near circumference.

In the optical system 10, the refractive power and the surface type arrangement of the first lens element L1 are advantageous for increasing the light entering brightness of the optical system and improving the image clarity, and are also advantageous for increasing the field angle of the optical system and widening the shooting range; the front and rear lens elements of the second lens element L2 have positive refractive power, and the total length of the system can be advantageously shortened and the system can be made to achieve aberration balance by making the second lens element L2 have the above-mentioned refractive power and surface shape setting; the surface design of the third lens element L3 is favorable for enhancing the strength of the positive refractive power, so as to be favorable for correcting the aberration generated by the objective lens; the fifth lens L5 can also correct the aberrations such as astigmatism and distortion generated by the objective lens; the design of the sixth lens L6 is beneficial to shortening the total length of the system; the seventh lens L7, by having the above-mentioned surface design, is beneficial to the optical system 10 to obtain a larger image surface to match the image sensor with higher pixels on the one hand, and can also increase the back focus of the optical system 10 on the other hand, thereby promoting the optical system 10 to have enough safety distance to avoid collision during the module assembling process. The refractive power and the surface shape of each lens element distributed from the object side to the image side are reasonably matched, so that the lens elements have a good telephoto property, and the aberration generated between the lens elements can be well balanced, thereby suppressing the overall aberration of the optical system 10 and achieving a better imaging effect.

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 of the optical system 10 from the object side to the image side are sequentially arranged in the order from top to bottom in table 1. The stop in the table is the aperture stop STO. Surfaces corresponding to surface numbers S1 and S2 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, the absolute value of the second value is the distance from the image-side surface of the lens to the surface of the next optical element (such as the object-side surface or the stop surface of the next lens) on the optical axis, and the value of the stop in the "thickness" parameter list represents the distance from the stop surface to the object-side surface of the next optical element on the optical axis. In the parameter tables of the following examples (first to eighth examples), the reference wavelength of the refractive index and the abbe number of each lens is 587.6nm, the reference wavelength of the focal length is 555nm, and the numerical units of the Y radius, the thickness, and the focal length (effective focal length) are 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 7.75mm, the f-number FNO is 2.60, the maximum field angle FOV is 43.57 °, and the total optical length TTL is 7.69 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.

It is to be noted that the first lens element L1, the second lens element L2, the fourth lens element L4 and the fifth lens element L5 are all made of glass, the third lens element L3, the sixth lens element L6 and the seventh lens element L7 are all made of plastic, and the object-side surface and the image-side surface of each lens element in the optical system 10 are both aspheric.

TABLE 2

Number of noodles

S1

S2

S3

S4

S5

S6

S7

K

5.565E-01

6.407E+00

-1.512E+00

-1.039E+00

-2.906E+00

9.900E+01

6.878E+01

A4

-3.270E-03

-4.421E-02

-9.650E-02

-7.823E-02

2.266E-02

2.043E-02

-9.300E-03

A6

-4.200E-03

4.707E-02

7.477E-02

1.063E-01

7.039E-02

-3.410E-03

-1.836E-02

A8

3.320E-03

-1.812E-02

-1.564E-02

-1.461E-01

-1.654E-01

-2.500E-02

-1.933E-02

A10

-1.570E-03

3.740E-03

-8.670E-03

1.609E-01

1.990E-01

3.395E-02

6.054E-02

A12

5.800E-04

-4.700E-04

6.560E-03

-1.048E-01

-1.269E-01

-1.999E-02

-6.690E-02

A14

-1.600E-04

4.000E-05

-1.910E-03

3.888E-02

4.574E-02

6.290E-03

4.213E-02

A16

3.000E-05

0.000E+00

3.000E-04

-8.190E-03

-9.410E-03

-1.090E-03

-1.578E-02

A18

0.000E+00

-2.000E-05

9.200E-04

1.030E-03

1.000E-04

3.210E-03

A20

0.000E+00

-4.000E-05

-5.000E-05

0.000E+00

-2.700E-04

Number of noodles

S8

S9

S10

S11

S12

S13

S14

K

-9.900E+01

-2.288E+01

-2.967E+01

-7.561E+01

6.657E+00

1.100E+01

-2.244E+01

A4

-2.139E-02

3.560E-03

-2.665E-02

-7.859E-02

-8.283E-02

-1.902E-01

-1.042E-01

A6

-3.210E-03

1.652E-02

5.095E-02

3.356E-02

4.973E-02

8.672E-02

3.872E-02

A8

-4.544E-02

-7.081E-02

-1.157E-01

-5.517E-02

-4.987E-02

-3.540E-02

-9.900E-03

A10

1.018E-01

1.251E-01

1.600E-01

3.353E-02

3.061E-02

8.530E-03

-5.700E-04

A12

-1.045E-01

-1.142E-01

-1.228E-01

-7.100E-04

-1.121E-02

-1.960E-03

1.330E-03

A14

5.968E-02

6.234E-02

5.695E-02

-8.530E-03

2.470E-03

6.700E-04

-4.600E-04

A16

-1.911E-02

-2.049E-02

-1.578E-02

3.950E-03

-3.100E-04

-1.500E-04

8.000E-05

A18

3.190E-03

3.670E-03

2.380E-03

-7.200E-04

2.000E-05

1.000E-05

-1.000E-05

A20

-2.100E-04

-2.700E-04

-1.500E-04

5.000E-05

0.000E+00

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

f/TTL is 1.009; f is the effective focal length of the optical system 10, and TTL is the distance on the optical axis from the object-side surface S1 of the first lens element L1 to the image plane S15 of the optical system 10. Satisfying the above relationship is advantageous for the optical system 10 to obtain a longer focal length to obtain a telephoto characteristic, and also advantageous for the overall length of the optical system 10 to be compressed to give the optical system 10 a relatively compact structure, thereby achieving a compact design of the optical system 10. In addition, when the relationship is satisfied, the optical system 10 is also beneficial to better processing the details of the far scene, so that the details of the focused far scene are more prominent, a good telephoto imaging effect is achieved, and a user obtains better shooting experience.

2 × Imgh/TTL ═ 1.092; imgh is half the image height corresponding to the maximum field angle of the optical system 10. By further satisfying the relationship, on the one hand, the optical system 10 can further achieve a telephoto imaging effect, and on the other hand, the optical system 10 can have a larger image plane size while maintaining miniaturization, thereby contributing to having a large image plane characteristic, and further being capable of better presenting the imaging details of the long shot, thereby improving the long shot performance of the optical system 10.

f123/R12 ═ 1.08; f123 is a combined focal length of the first lens L1, the second lens L2, and the third lens L3, and R12 is a curvature radius of the image-side surface S2 of the first lens L1 at the optical axis. When the relationship is satisfied, on one hand, the positive refractive power strength of a lens group formed by the first three lenses in the optical system 10 can be reasonably controlled, and the image side surface S2 surface type of the first lens L1 is matched, so that incident light can be well regulated and controlled when entering the optical system 10, and thus the air gaps between every two adjacent lenses in the optical system 10 can be effectively reduced, and the total length of the system is further reduced; on the other hand, it is also helpful to control the shape of the image side surface S2 of the first lens L1, so that the aberrations generated by the image side lens can be balanced.

f 567/f-0.96; f567 is a combined focal length of the fifth lens L5, the sixth lens L6, and the seventh lens L7. When the relationship is satisfied, it is beneficial to balance the spherical aberration and chromatic aberration generated by the object lens, and can effectively avoid the excessive concentration of the refractive power strength of the optical system 10 on the rear lens group, thereby better improving the system aberration correction capability. Meanwhile, satisfying this relationship also effectively reduces the length of the optical system 10 while emphasizing the telephoto characteristic of the optical system 10.

f/f3 is 1.28; f3 is the effective focal length of the third lens L3. When the relationship is satisfied, the total effective focal length of the optical system 10 and the effective focal length of the third lens L3 can be reasonably configured, so that the surface shape of the third lens L3 is suitable, which not only helps to reduce the incident angle of light rays on the lens and reduce the tolerance sensitivity of the third lens L3, but also is beneficial to the optical system 10 to have a telephoto characteristic.

ct56/et56 equals 4.18; ct56 is the distance on the optical axis from the image-side surface S10 of the fifth lens L5 to the object-side surface S11 of the sixth lens L6, and et56 is the distance on the optical axis from the maximum effective aperture of the image-side surface S10 of the fifth lens L5 to the maximum effective aperture of the object-side surface S11 of the sixth lens L6. When the relationship is satisfied, the distance between the fifth lens L5 and the sixth lens L6 on the optical axis and the distance between the fifth lens L5 and the sixth lens L6 at the maximum effective diameter can be reasonably configured, so that the light deflection angle between the fifth lens L5 and the sixth lens L6 can be reduced, and the tolerance sensitivity of the two lenses can be reduced; on the other hand, the assembly between the fifth lens L5 and the sixth lens L6 is also facilitated; in addition, it also helps to reduce the size of the rear end of the optical system 10.

0.456 is provided with | sag61|/et6 |; sag61 is the rise of the object-side surface S11 of the sixth lens L6 at the maximum effective aperture, and et6 is the thickness from the object-side surface S11 of the sixth lens L6 at the maximum effective aperture to the image-side surface S12 at the maximum effective aperture in the optical axis direction. When the above relationship is satisfied, it is helpful to control the inclination angle of the object-side surface S11 of the sixth lens L6 at the edge, so that the surface profile from the center to the edge can be smoothly transited, and the edge light can also realize the transition to the subsequent lens to the image plane S15 at a relatively gentle angle; on the other hand, the edge thickness of the sixth lens L6 can be controlled within a reasonable range, which is beneficial to controlling the thickness ratio of the whole lens so as not to be too large or too small, thereby reducing the difficulty of molding and assembling the lens.

sag71/et7 ═ 1.82; sag71 is the sagittal height of the object-side surface S13 of the seventh lens L7 at the maximum effective aperture, and et7 is the thickness from the object-side surface S13 of the seventh lens L7 at the maximum effective aperture to the image-side surface S14 at the maximum effective aperture in the optical axis direction. When the above relationship is satisfied, the opening angle of the seventh lens at the edge of the lens can be effectively controlled, so that the incident light can enter the seventh lens L7 at a smaller incident angle and smoothly pass through the seventh lens L7 to reach the imaging surface S15, thereby facilitating the realization of a large image surface characteristic of the optical system 10 and further significantly improving the imaging quality.

f1/CT1 is 16.08; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 on the optical axis. When this relationship is satisfied, the refractive power strength and the center thickness of the first lens element L1 can be well matched, so that the optical aberration of the optical system 10 can be corrected and the feasibility of the lens forming process can be improved.

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 optical 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 images. Fig. 2 also includes a Distortion map (Distortion) of the optical system 10, and it can be seen from the map that the image Distortion caused by the main beam is small, and the maximum Distortion is controlled within 2.5%, so that it can be judged that the imaging quality of the optical system 10 is excellent.

Second embodiment

Referring to fig. 3 and 4, in the second embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 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 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; the object-side surface S5 is convex at the near circumference, and the image-side surface S6 is concave at the near 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 names and parameters of the elements can be obtained from the first embodiment, which is not repeated herein.

TABLE 3

TABLE 4

Number of noodles

S1

S2

S3

S4

S5

S6

S7

K

3.472E-01

4.415E+00

-9.897E-01

-8.015E-01

-1.812E+00

-9.900E+01

9.900E+01

A4

-4.140E-03

-4.884E-02

-9.174E-02

-7.528E-02

6.100E-03

1.809E-02

-3.105E-02

A6

-3.710E-03

4.772E-02

7.609E-02

8.432E-02

5.718E-02

-1.524E-02

5.680E-03

A8

3.320E-03

-1.821E-02

-2.236E-02

-9.632E-02

-1.290E-01

2.884E-02

-5.546E-02

A10

-1.960E-03

3.760E-03

-2.820E-03

1.047E-01

1.755E-01

-4.880E-02

1.386E-01

A12

8.000E-04

-4.700E-04

4.400E-03

-6.541E-02

-1.246E-01

4.990E-02

-1.771E-01

A14

-2.300E-04

4.000E-05

-1.540E-03

2.250E-02

5.090E-02

-2.806E-02

1.337E-01

A16

4.000E-05

0.000E+00

2.700E-04

-4.310E-03

-1.221E-02

8.540E-03

-5.886E-02

A18

0.000E+00

-2.000E-05

4.300E-04

1.600E-03

-1.320E-03

1.373E-02

A20

0.000E+00

-2.000E-05

-9.000E-05

8.000E-05

-1.300E-03

Number of noodles

S8

S9

S10

S11

S12

S13

S14

K

-9.900E+01

1.694E+01

-3.402E+01

4.728E+01

5.653E+00

1.100E+01

-1.840E+01

A4

-4.560E-02

8.790E-03

1.110E-02

-5.535E-02

-9.082E-02

-1.804E-01

-8.680E-02

A6

1.131E-02

-2.250E-03

3.150E-03

4.588E-02

9.189E-02

8.337E-02

3.182E-02

A8

-4.579E-02

-5.998E-02

-7.625E-02

-9.462E-02

-1.039E-01

-3.707E-02

-9.160E-03

A10

9.186E-02

1.101E-01

1.027E-01

6.435E-02

6.885E-02

1.334E-02

9.900E-04

A12

-9.170E-02

-9.080E-02

-5.634E-02

-1.307E-02

-2.763E-02

-4.870E-03

3.200E-04

A14

5.198E-02

4.392E-02

1.328E-02

-4.770E-03

6.890E-03

1.490E-03

-1.600E-04

A16

-1.661E-02

-1.278E-02

2.500E-04

2.920E-03

-1.040E-03

-2.700E-04

3.000E-05

A18

2.760E-03

2.030E-03

-7.200E-04

-5.400E-04

9.000E-05

2.000E-05

0.000E+00

A20

-1.900E-04

-1.300E-04

1.000E-04

3.000E-05

0.000E+00

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

as can be seen from the aberration diagram in fig. 4, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.05mm, and the maximum distortion is controlled within 2.5%, so that the optical system 10 of this embodiment has excellent imaging quality.

Third embodiment

Referring to fig. 5 and 6, in the third embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with positive refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 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.

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

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

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 names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

TABLE 5

TABLE 6

Number of noodles

S1

S2

S3

S4

S5

S6

S7

K

2.926E-01

3.604E+00

-1.007E+00

-7.026E-01

-1.372E+00

8.365E+01

-9.900E+01

A4

-4.860E-03

-6.343E-02

-9.836E-02

-5.648E-02

2.011E-02

6.500E-03

-4.422E-02

A6

-3.240E-03

5.533E-02

7.317E-02

5.446E-02

3.162E-02

-1.178E-02

2.632E-02

A8

3.270E-03

-2.012E-02

-1.006E-02

-7.243E-02

-1.153E-01

3.005E-02

-1.020E-01

A10

-2.420E-03

4.020E-03

-1.451E-02

9.286E-02

1.747E-01

-4.689E-02

2.328E-01

A12

1.230E-03

-4.900E-04

1.023E-02

-6.089E-02

-1.255E-01

4.503E-02

-3.004E-01

A14

-4.000E-04

4.000E-05

-3.210E-03

2.111E-02

5.096E-02

-2.397E-02

2.313E-01

A16

8.000E-05

0.000E+00

5.500E-04

-4.020E-03

-1.213E-02

6.900E-03

-1.042E-01

A18

-1.000E-05

0.000E+00

-5.000E-05

4.000E-04

1.580E-03

-1.010E-03

2.496E-02

A20

0.000E+00

-2.000E-05

-9.000E-05

6.000E-05

-2.440E-03

Number of noodles

S8

S9

S10

S11

S12

S13

S14

K

9.900E+01

-1.001E+01

-2.331E+01

6.571E+00

5.004E+00

1.088E+01

-1.897E+01

A4

-4.841E-02

9.100E-04

7.800E-04

-3.778E-02

-5.243E-02

-1.821E-01

-1.039E-01

A6

1.759E-02

-4.920E-03

-1.935E-02

-1.622E-02

3.468E-02

7.978E-02

4.194E-02

A8

-4.246E-02

-1.811E-02

-2.930E-03

-2.670E-02

-6.050E-02

-2.693E-02

-1.318E-02

A10

7.769E-02

5.853E-02

2.865E-02

2.776E-02

4.842E-02

2.770E-03

1.470E-03

A12

-7.579E-02

-6.105E-02

-1.769E-02

-4.800E-03

-2.171E-02

-2.000E-05

5.100E-04

A14

4.235E-02

3.417E-02

1.420E-03

-4.390E-03

5.850E-03

4.300E-04

-2.500E-04

A16

-1.331E-02

-1.090E-02

2.390E-03

2.380E-03

-9.400E-04

-1.700E-04

5.000E-05

A18

2.170E-03

1.840E-03

-9.100E-04

-4.500E-04

8.000E-05

2.000E-05

-1.000E-05

A20

-1.400E-04

-1.300E-04

1.000E-04

3.000E-05

0.000E+00

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

f/TTL	1.020	ct56/et56	5.62
				2*Imgh/TTL	1.094	\|sag61\|/et6	0.516
f123/R12	1.53	sag71/et7	-1.98
				f567/f	-1.02	f1/CT1	14.33
f/f3	1.09

as can be seen from the aberration diagram in fig. 6, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.025mm, and the maximum distortion is controlled to be about 2.5%, so that the imaging quality of the optical system 10 is excellent.

Fourth embodiment

Referring to fig. 7 and 8, in the fourth embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with positive refractive power, and the seventh lens element L7 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 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 object-side surface S9 is convex near the circumference, and the image-side surface S10 is convex near 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 names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

TABLE 7

TABLE 8

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

f/TTL	1.032	ct56/et56	4.83
				2*Imgh/TTL	1.111	\|sag61\|/et6	0.708
f123/R12	1.42	sag71/et7	-2.52
				f567/f	-2.08	f1/CT1	15.50
f/f3	1.29

as can be seen from the aberration diagram in fig. 8, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.025mm, and the maximum distortion is controlled to be about 2.5%, so that the imaging quality of the optical system 10 is excellent.

Fifth embodiment

Referring to fig. 9 and 10, in the fifth embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 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 concave at the paraxial region thereof, and the image-side surface S8 is concave at the paraxial region thereof; object side S7 is concave near the circumference, and image side S8 is concave near 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 convex at the paraxial region thereof; the object-side surface S9 is convex at the near circumference, and the image-side surface S10 is concave at the near circumference.

The object-side surface S11 of the sixth lens element L6 is concave at the paraxial region, and the image-side surface S12 is concave at the paraxial region; object side S11 is concave near the circumference, and image side S12 is concave near 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 names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

TABLE 9

Watch 10

Number of noodles

S1

S2

S3

S4

S5

S6

S7

K

2.405E-01

3.515E+00

-9.017E-01

-9.586E-01

-1.058E+00

-9.338E+01

-9.900E+01

A4

1.100E-04

-8.960E-03

-7.232E-02

-9.346E-02

3.400E-03

3.145E-02

-2.300E-02

A6

-3.800E-03

1.860E-02

6.002E-02

9.605E-02

5.832E-02

-1.231E-02

1.980E-03

A8

1.760E-03

-8.470E-03

-3.289E-02

-8.242E-02

-7.388E-02

1.538E-02

-4.413E-02

A10

-4.800E-04

1.810E-03

1.200E-02

5.963E-02

7.983E-02

-2.535E-02

1.177E-01

A12

-9.000E-05

-2.200E-04

-1.320E-03

-2.692E-02

-5.459E-02

2.288E-02

-1.576E-01

A14

3.000E-05

2.000E-05

-6.400E-04

7.050E-03

2.304E-02

-1.149E-02

1.252E-01

A16

1.000E-05

0.000E+00

2.500E-04

-1.050E-03

-5.740E-03

3.210E-03

-5.716E-02

A18

0.000E+00

-3.000E-05

8.000E-05

7.600E-04

-4.600E-04

1.354E-02

A20

0.000E+00

-4.000E-05

3.000E-05

-1.280E-03

Number of noodles

S8

S9

S10

S11

S12

S13

S14

K

6.745E+01

5.482E+01

-9.403E+00

4.950E+01

5.087E+00

9.691E+00

-2.350E+01

A4

-3.781E-02

1.078E-02

4.916E-02

5.527E-02

-1.356E-02

-1.707E-01

-9.181E-02

A6

1.840E-03

-3.668E-02

-9.321E-02

-1.406E-01

-2.738E-02

8.370E-02

3.209E-02

A8

-1.476E-02

3.251E-02

7.767E-02

1.073E-01

-1.460E-03

-4.452E-02

-9.640E-03

A10

5.069E-02

-2.154E-02

-5.223E-02

-8.052E-02

1.129E-02

1.984E-02

1.210E-03

A12

-6.300E-02

1.052E-02

3.156E-02

5.363E-02

-6.220E-03

-7.510E-03

2.900E-04

A14

4.495E-02

-2.300E-03

-1.508E-02

-2.467E-02

1.660E-03

2.020E-03

-1.700E-04

A16

-1.786E-02

-3.000E-05

4.950E-03

6.820E-03

-2.300E-04

-3.200E-04

4.000E-05

A18

3.580E-03

8.000E-05

-9.300E-04

-1.010E-03

2.000E-05

0.000E+00

A20

-2.800E-04

-1.000E-05

7.000E-05

6.000E-05

0.000E+00

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

f/TTL	1.024	ct56/et56	2.97
				2*Imgh/TTL	1.099	\|sag61\|/et6	0.745
f123/R12	1.26	sag71/et7	-2.18
				f567/f	-1.77	f1/CT1	16.74
f/f3	1.45

as can be seen from the aberration diagram in fig. 10, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.025mm, and the maximum distortion is controlled to be about 2.5%, so that the imaging quality of the optical system 10 is excellent.

Sixth embodiment

Referring to fig. 11 and 12, in the sixth embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 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 names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

TABLE 11

TABLE 12

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

f/TTL	1.015	ct56/et56	5.14
				2*Imgh/TTL	1.105	\|sag61\|/et6	0.752
f123/R12	1.07	sag71/et7	-1.16
				f567/f	-1.12	f1/CT1	23.03
f/f3	1.36

as can be seen from the aberration diagram in fig. 12, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.025mm, and the maximum distortion is controlled to be about 2.5%, so that the imaging quality of the optical system 10 is excellent.

Seventh embodiment

Referring to fig. 13 and 14, in the seventh embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 with negative refractive power. Fig. 14 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in the seventh embodiment.

In addition, the lens parameters of the optical system 10 in the seventh embodiment are given in tables 13 and 14, wherein the definitions of the names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

Watch 13

TABLE 14

Number of noodles

S1

S2

S3

S4

S5

S6

S7

K

1.997E-01

3.463E+00

-1.499E+00

-9.003E-01

-4.002E+00

5.801E+01

3.436E+01

A4

-1.900E-04

-3.066E-02

-8.195E-02

-7.565E-02

1.365E-02

-9.600E-04

-3.398E-02

A6

-4.230E-03

2.421E-02

4.031E-02

2.860E-02

5.830E-03

6.500E-03

1.800E-02

A8

3.420E-03

-6.010E-03

4.570E-03

6.160E-03

-1.217E-02

-8.500E-03

-1.457E-02

A10

-1.860E-03

4.500E-04

-1.173E-02

7.400E-04

2.776E-02

4.670E-03

5.160E-03

A12

6.300E-04

5.000E-05

5.810E-03

-3.730E-03

-2.030E-02

-3.800E-04

7.210E-03

A14

-1.500E-04

-1.000E-05

-1.660E-03

1.390E-03

7.250E-03

-5.600E-04

-1.081E-02

A16

3.000E-05

0.000E+00

2.900E-04

-2.100E-04

-1.300E-03

2.200E-04

6.010E-03

A18

0.000E+00

-3.000E-05

1.000E-05

9.000E-05

-3.000E-05

-1.570E-03

A20

0.000E+00

1.600E-04

Number of noodles

S8

S9

S10

S11

S12

S13

S14

K

-9.900E+01

1.553E+01

-9.708E+00

-7.459E+00

5.582E+00

8.364E+00

-1.993E+01

A4

-4.643E-02

-1.933E-02

-2.061E-02

-8.126E-02

-1.024E-01

-1.319E-01

-5.958E-02

A6

1.672E-02

1.147E-02

2.045E-02

9.139E-02

9.686E-02

5.522E-02

1.436E-02

A8

-1.357E-02

-3.729E-02

-6.502E-02

-1.722E-01

-1.160E-01

-2.328E-02

-1.530E-03

A10

4.950E-03

6.582E-02

9.402E-02

1.636E-01

8.471E-02

8.830E-03

-9.800E-04

A12

5.920E-03

-6.712E-02

-8.085E-02

-9.847E-02

-4.007E-02

-3.110E-03

5.700E-04

A14

-8.720E-03

4.409E-02

4.560E-02

3.724E-02

1.227E-02

7.800E-04

-1.500E-04

A16

4.510E-03

-1.719E-02

-1.578E-02

-8.290E-03

-2.310E-03

-1.100E-04

2.000E-05

A18

-1.040E-03

3.480E-03

2.980E-03

9.800E-04

2.400E-04

1.000E-05

0.000E+00

A20

9.000E-05

-2.800E-04

-2.300E-04

-5.000E-05

-1.000E-05

0.000E+00

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

f/TTL	1.005	ct56/et56	3.45
				2*Imgh/TTL	1.097	\|sag61\|/et6	0.947
f123/R12	1.14	sag71/et7	-1.21
				f567/f	-1.04	f1/CT1	18.68
f/f3	1.38

as can be seen from the aberration diagrams in fig. 14, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, in which the tangential field curvature and the sagittal field curvature are controlled within 0.025mm, and the maximum distortion is controlled to about 5%, so that the imaging quality of the optical system 10 is excellent.

Eighth embodiment

Referring to fig. 15 and 16, in the eighth embodiment, the optical system 10 includes, in order from the object side to the image side along the optical axis 101, 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 aperture stop STO, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power, the sixth lens element L6 with negative refractive power, and the seventh lens element L7 with negative refractive power. Fig. 16 includes a longitudinal spherical aberration diagram, an astigmatism diagram, and a distortion diagram of the optical system 10 in the eighth embodiment.

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 concave at the paraxial region thereof; the object side S7 is concave near the circumference and the image side S8 is convex near the circumference.

The object-side surface S11 of the sixth lens element L6 is concave at the paraxial region, and the image-side surface S12 is concave at the paraxial region; the object side S11 is concave near the circumference and the image side S12 is convex near the circumference.

In addition, the lens parameters of the optical system 10 in the eighth embodiment are given in tables 15 and 16, wherein the definitions of the names and parameters of the elements can be found in the first embodiment, which is not repeated herein.

Watch 15

TABLE 16

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

f/TTL	1.092	ct56/et56	6.60
				2*Imgh/TTL	1.167	\|sag61\|/et6	1.003
f123/R12	1.59	sag71/et7	-1.57
				f567/f	-0.93	f1/CT1	16.43
f/f3	1.59

as can be seen from the aberration diagram in fig. 16, the longitudinal spherical aberration, the field curvature, and the distortion of the optical system 10 are well controlled, wherein the meridional field curvature and the sagittal field curvature are controlled within 0.05mm, and the maximum distortion is controlled within 2.5%, so that the imaging quality of the optical system 10 is excellent.

The optical system 10 in the first to eighth embodiments can compress the length of the system and have the telephoto characteristic through reasonable combination design of the characteristics of the seven lenses, such as refractive power, surface structure, parameter relationship, and the like, and can be matched with an image sensor having a larger-sized photosensitive surface, so that the optical system 10 can achieve better processing on long-range details on the basis of meeting the requirement of miniaturization design, and further achieve an imaging effect of compressing the shooting distance.

Referring to fig. 17, 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 S15 of the optical system 10 overlaps the photosensitive surface of the image sensor 210 when assembled.

By adopting the optical system 10 in any of the above embodiments, the camera module 20 will have a telephoto characteristic, so that the long-range details can be better processed, and further, the camera module has excellent telephoto performance; the length of the camera module 20 can be compressed to realize miniaturization design, so that the occupied space in the thickness direction of the equipment can be reduced, and the ultrathin design of the equipment is facilitated.

Referring to fig. 18, 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 includes, but is not limited to, a smart phone, a smart watch, smart glasses, an electronic book reader, a vehicle-mounted camera device, 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. Through adopting above-mentioned module 20 of making a video recording, electronic equipment 30 can make a video recording module 20 with the space assembly that littleer, can also be through making a video recording module 20 in order to obtain good long-range scene shooting effect simultaneously.

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 express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. an optical system, it is characterized in that, along the optical axis from the object side to the image side sequentially comprising:

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

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

a third lens with positive refractive power, the object side of the third lens is convex at the near optical axis;

a fourth lens with refractive power;

a fifth lens with refractive power, the image side of the fifth lens is convex at the near optical axis;

a sixth lens with refractive power, the image side of the sixth lens is concave at the near optical axis;

The seventh lens with refractive power, the object side of the seventh lens is convex at the near optical axis, the image side is concave at the near optical axis, the object side and the image side are aspherical, and the object side and the image side are aspherical. At least one of the inflection points exists;

The optical system also satisfies the relation:

1.004 < f/TTL < 1.1; and

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

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

1.09＜2*Imgh/TTL＜1.2;

Imgh is half of the image height corresponding to the maximum angle of view of the optical system.

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

1<f123/R12<1.8;

f123 is the combined focal length of the first lens, the second lens and the third lens, and R12 is the radius of curvature of the image side of the first lens at the optical axis.

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

-2.2＜f567/f＜-0.9;

f567 is the combined focal length of the fifth lens, the sixth lens and the seventh lens.

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

1<f/f3<1.6;

f3 is the effective focal length of the third lens.

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

2.5<ct56/et56<7;

ct56 is the distance from the image side of the fifth lens to the object side of the sixth lens on the optical axis, et56 is the maximum effective aperture of the image side of the fifth lens to the object side of the sixth lens. The distance of the effective aperture in the direction of the optical axis.

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

0.4＜|sag61|/et6＜1.1;

sag61 is the sag of the object side of the sixth lens at the maximum effective aperture, et6 is the thickness of the sixth lens from the object side of the maximum effective aperture to the image side of the maximum effective aperture in the direction of the optical axis.

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

-3<sag71/et7<-1;

sag71 is the sagittal height of the object side of the seventh lens at the maximum effective aperture, and et7 is the thickness of the seventh lens from the object side of the maximum effective aperture to the image side of the maximum effective aperture in the direction of the optical axis.

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

14<f1/CT1<23.5;

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

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

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