WO2021195884A1

WO2021195884A1 - Optical system, photography device, and movable platform

Info

Publication number: WO2021195884A1
Application number: PCT/CN2020/082197
Authority: WO
Inventors: 甘汝婷
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2020-03-30
Filing date: 2020-03-30
Publication date: 2021-10-07
Also published as: CN112771431B; CN112771431A

Abstract

An optical system, a photography device, and a movable platform. The optical system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens sequentially arranged from an object side to an image side. The first lens, the second lens, the fifth lens, and the seventh lens have negative focal power. The third lens, the fourth lens, and the sixth lens have positive focal power. The optical system satisfies the following expressions: 1.5<|f₁/f|<2.5, 4<|(f₂+f₁)/f|<6, 1<|f₃/f|<2, 1<|f₄/f|<2, 0.9<|f₅/f|<1.5, 0.9<|f₅/f₆|<1.5, 4.5<|f₇/f₆|<6, 4.5<|f₇/f|<6, 4<|TL/f|<5, and 0.2<|BFL/TL|<0.5, wherein f is the focal length of the optical system, f₁ to f₇ are the focal lengths of the first lens to the seventh lens, respectively, TL is the distance on an optical axis from the center of the lens surface of the first lens close to the object side to the imaging surface, and BFL is the distance on the optical axis from the center of the lens surface of the seventh lens close to the image side to the imaging surface.

Description

Optical system, shooting device and movable platform

Technical field

This application relates to the field of optical technology, and in particular to an optical system, a photographing device using the optical system, and a movable platform.

Background technique

With the development of technology, photographic lenses with small size, high image quality, low cost, and large field of view are becoming more and more popular. Most of the existing compact cameras such as drones and sports camera lenses require ultra-high optical quality, and the shooting range requires a certain macro function, but the image surface of the existing sports camera lenses is mostly less than 1 inch (inch), the image surface is small, the aperture is small; and they are all fixed focal lengths, do not have the focus function or the overall lens focus, will cause the total length of the lens to change; and cannot be exchanged, can only shoot objects in a certain range or a certain focal range , It is difficult to meet the diversified needs of a large range, so it can not meet the needs of users.

Summary of the invention

Based on this, the present application provides an optical system, a photographing device, and a movable platform. The optical system is used to increase the field of view of the photographing device and at the same time improve the imaging quality.

In the first aspect, the present application provides an optical system including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in order from the object side to the image side And a seventh lens, the first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power, and the third lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

1.5<|f ₁ /f|<2.5, ₄ <|(f 2 +f ₁ )/f|<6, 1<|f ₃ /f|<2, 1<|f ₄ /f|<2, 0.9 _{_{<| f 5 /f|<1.5,0.9<|f 5 / f}} 6 | <1.5,4.5 <| f 7 / f 6 | <6,4.5 <| f 7 / f | <6,4 <| TL / f|<5, 0.2<|BFL/TL|<0.5;

Where f is the focal length of the optical system, f ₁ is the focal length of the first lens, f ₂ is the focal length of the second lens, f ₃ is the focal length of the third lens, and f ₄ is the first lens. The focal length of the four lenses, f ₅ is the focal length of the fifth lens, f ₆ is the focal length of the sixth lens, f ₇ is the focal length of the seventh lens, and TL is the lens near the object side of the first lens The distance on the optical axis from the surface center to the imaging surface; BFL is the distance on the optical axis from the center of the lens surface of the seventh lens near the image side to the imaging surface.

In a second aspect, the present application also provides a photographing device. The photographing device includes an optical system and a photographing device. The optical system is connected to the photographing device. The optical system includes The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens, the first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power , The third lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

In a third aspect, the present application also provides a movable platform. The movable platform includes a platform body and a photographing device, the photographing device is mounted on the platform body; the photographing device includes an optical system and a photographing device, The optical system is connected to the photographing device, and the optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a first lens, which are sequentially arranged from the object side to the image side. Seven lenses, the first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power, and the third lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

The optical system, the photographing device and the movable platform provided by the embodiments of the present application, wherein the optical system can be detachably installed on the photographing device, and the photographing device can be installed on the main body of the movable platform. The optical system utilizes seven The combination of lenses and specific parameter settings increase the field of view of the shooting device, and at the same time improve the imaging quality of the shooting device.

It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the application.

Description of the drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the following will briefly introduce the drawings used in the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. Ordinary technicians can obtain other drawings based on these drawings without creative work.

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

2 is a schematic diagram of the configuration of an optical system provided by an embodiment of the present application;

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

4 is a schematic structural diagram of an optical system provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of another view angle of the optical system provided by an embodiment of the present application;

FIG. 6 is a schematic structural diagram of a photographing device provided by an embodiment of the present application;

Fig. 7 is a schematic structural diagram of a movable platform provided by an embodiment of the present application.

Description of main components and symbols:

100. Optical system; 101, first lens; 102, second lens; 103, third lens, 104, fourth lens; 105, fifth lens; 106, sixth lens; 107, seventh lens;

200. Shooting device; 21. Shooting equipment; 210. Lens group; 211. Display screen; 212. Shooting button;

300. Movable platform; 310. Platform ontology.

Detailed ways

The technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

Hereinafter, some embodiments of the present application will be described in detail with reference to the accompanying drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

It should also be understood that the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in the specification of this application and the appended claims, unless the context clearly indicates other circumstances, the singular forms "a", "an" and "the" are intended to include plural forms.

It should be further understood that the term "and/or" used in the specification and appended claims of this application refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations .

Please refer to FIG. 1. FIG. 1 is a schematic structural diagram of an optical system provided by an embodiment of the present application. The optical system can be used to increase the angle of view of the shooting device, and at the same time can improve the imaging quality.

As shown in Figure 1, the optical system 100 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106 and The seventh lens 107. Among them, the first lens 101, the second lens 102, the fifth lens 105, and the seventh lens 107 have negative refractive power, and the third lens 103, the fourth lens 104, and the sixth lens 106 have positive refractive power.

Among them, the optical system 100 also satisfies the following expression:

1.5<|f ₁ /f|<2.5, ₄ <|(f 2 +f ₁ )/f|<6, 1<|f ₃ /f|<2, 1<|f ₄ /f|<2, 0.9 _{_{<| f 5 /f|<1.5,0.9<|f 5 / f}} 6 | <1.5,4.5 <| f 7 / f 6 | <6,4.5 <| f 7 / f | <6,4 <| TL / f|<5, 0.2<|BFL/TL|<0.5 (1)

In Expression (1), f is the focal length of optical system 100, f ₁ is the focal length of the first lens 101, f ₂ is the focal length of the second lens 102, f is the focal length of the third _{lens. 3} 103, _{f. 4} are The focal length of the four lens 104, f ₅ is the focal length of the fifth lens 105, f ₆ is the focal length of the sixth lens 106, f ₇ is the focal length of the seventh lens 107, and TL is the lens surface center of the first lens 101 near the object side. The distance on the optical axis from the imaging surface I; BFL is the distance from the center of the lens surface of the seventh lens 107 on the image side to the imaging surface I on the optical axis.

It should be noted that the limit of 4.5<|TL/f|<5 helps to shorten the overall length of the optical system 100, and the limit of 0.2<|BFL/TL|<0.5 helps to improve the optical system 100 The focal length, because the back focal length is longer, the image sensor is farther away from the mirror of the optical system. Therefore, the image of dust on the image surface is relatively weak, thereby preventing the influence of dust on the image surface.

Wherein, the aperture stop S of the optical system 100 is located between the third lens 103 and the fourth lens 104. In some embodiments, the distance between the positions of the aperture stop S of the optical system 100 is greater than 4 mm, where the distance between the positions is the distance between two lenses adjacent to the aperture stop S, specifically the third The distance between the lens 103 and the fourth lens 104. The aperture stop S can be realized with a variable diaphragm, and the position interval is greater than 4mm, which is beneficial to set the variable diaphragm, that is, it facilitates the realization of the mechanical structure of the variable diaphragm, thereby facilitating the design of the optical system diaphragm.

Through the combination of seven lenses, the optical system provided by the above-mentioned embodiments can increase the field of view of the optical system. At the same time, the optical system has a compact structure. The total length of the system is shortened, that is, the total length of the entire internal focusing optical system of the optical system (the distance from the vertex of the object side of the first lens 101 to the imaging surface I) is less than 29mm, and the entire lens system (the vertex of the object side of the first lens 101 to the seventh The apex distance of the image side of the lens 107 is less than 23 mm, so that the optical system can be miniaturized, lightened, and portable.

In some embodiments, in order to further reduce the weight of the optical system and realize the lightweight and portability of the optical system, the optical system 100 includes at least one lens made of plastic material. Of course, the seven lenses of the optical system 100 may also include at least one lens made of glass.

Exemplarily, for example, the second lens 102 is made of plastic material, and several other lenses are made of common materials such as glass; or, for example, the second lens 102 is made of glass material, and the other lenses are made of common materials such as plastic.

In some embodiments, in order to further reduce the volume and weight of the optical system while ensuring imaging quality, at least one of the second lens 102, the fifth lens 105, and the seventh lens 107 is a lens made of plastic.

Exemplarily, in the optical system 100, the first lens 101 and the seventh lens 107 may be made of glass, and the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, and the sixth lens 106 may be made of plastic. The material can not only reduce the weight of the optical system, but also prevent the lens of the optical system from scratching.

In some embodiments, in order to improve the imaging quality of the optical system, at least one lens in the optical system 100 is an aspheric lens. Among them, an aspheric lens means that at least one of the two lens surfaces of the lens is aspheric.

In particular, at least one of the two lens surfaces of at least one of the second lens 102, the fifth lens 105, the sixth lens 106, and the seventh lens 107 is aspherical. It can effectively correct the distortion and chromatic aberration caused by an excessively large field of view, and can also improve the overall resolution of the optical system and realize the miniaturization of the lens.

Exemplarily, at least one of the two lens surfaces of at least one of the second lens 102, the fifth lens 105, the sixth lens 106, and the seventh lens 107 is aspherical. Of course, both lens surfaces may be Aspherical.

Specifically, as shown in FIG. 2, at least one of the lens surface 3 and the lens surface 4 of the second lens 102 is aspherical; and/or, at least one of the lens surface 10 and the lens surface 11 of the fifth lens 105 is a mirror surface Is an aspherical surface; and/or, at least one of the lens surface 12 and the lens surface 13 of the sixth lens 106 is aspherical; and/or, at least one of the lens surface 14 and the lens surface 15 of the seventh lens 107 has a mirror surface It is aspherical. Of course, all of them may be aspherical.

In particular, at least one of the two lens surfaces of each of the second lens 102, the fifth lens 105, the sixth lens 106, and the seventh lens 107 is aspherical. It can more effectively correct the distortion and chromatic aberration caused by an excessively large field of view, and can also improve the overall resolution of the optical system and realize the miniaturization of the lens.

Specifically, as shown in FIG. 2, at least one of the lens surface 3 and the lens surface 4 of the second lens 102 is aspherical; and at least one of the lens surface 10 and the lens surface 11 of the fifth lens 105 is aspherical; At least one of the lens surface 12 and the lens surface 13 of the sixth lens 106 is aspherical; and at least one of the lens surface 14 and the lens surface 15 of the seventh lens 107 is aspherical. Of course, all of them may be aspherical.

In some embodiments, the distance from the center vertex of the lens surface of the seventh lens 107 close to the image side to the imaging surface I is greater than a preset distance. Through the setting of the preset distance, such as setting the preset distance to 5.6mm, the safety of the optical system during use can be ensured, and at the same time, it can help reduce the impact of dust on the image quality and reserve space. For the realization of the mechanical structure of interchangeable lenses.

In some embodiments, at least one of the second lens 102 to the seventh lens 107 of the optical system 100 can be used as an internal focusing lens group, of course, two lenses can also be combined as an internal focusing lens group. Thus, the focus can be realized from the object at infinity (or the object at the closest distance) to the object at the closest distance (or the object at infinity), especially the shooting effect is better at different object distances in the range of 0.3m to infinity. This solves the problem that the existing lens can only shoot objects in a certain range or a certain focal range.

At least one of the second lens 102 to the seventh lens 107 of the optical system 100 can be used as an inner focusing lens group, which can well control the aberration caused by the focusing lens during the movement process, thereby improving the overall optical system 100 Optical image quality.

Among them, through the design of the focusing structure, it is also necessary to ensure that the distance between the focusing lens and the adjacent lens during internal focusing is at least greater than 1.1 mm. It can effectively avoid the collision of the front and rear mechanical structures used for the focusing lens, and ensure the safety of the optical system.

Exemplarily, for example, the fourth lens 104 is used as the inner focusing lens group, and the interval between the fourth lens 104 and the adjacent lenses (the third lens 103 and the fourth lens 105) during internal focusing is at least greater than 1.1 mm.

In some embodiments, when at least one of the second lens 102 to the seventh lens 107 of the optical system 100 can be used as the inner focusing lens group, the adjustment amount corresponding to the inner focusing lens group is less than 0.5 mm, and the optical system The breathing effect is small, and the change in the field of view of the picture is less than 0.5°, thereby improving the image quality. Secondly, during internal focusing, the focus group weight can also be controlled to be less than 0.2g, so the focusing speed is improved, and good performance can be obtained when focusing at close range. Thirdly, it can also be ensured that the field of view of the optical system 100 is greater than 115°, thereby increasing the field of view of the shooting device, so that the shooting field of view is larger.

In some embodiments, in order to correct the chromatic aberration of the optical system and improve the imaging quality, the optical system 100 satisfies the following expression:

(vd ₁ ,vd ₄ ,vd ₆ )>40,0<(vd ₂ ,vd ₃ ,vd ₅ ,vd ₇ )<40 (2)

In expression (2), vd ₁ , vd ₂ , vd ₃ , vd ₄ , vd ₅ , vd ₆ , and vd ₇ are the first lens 101, the second lens 102, the third lens 103, the fourth lens 104, Dispersion coefficients of the fifth lens 105, the sixth lens 106, and the seventh lens 107.

In particular, the second lens 102, the fifth lens 105, the sixth lens 106, and the seventh lens 107 in the optical system 100 satisfy the following expression: 0<(vd ₂ ,vd ₅ ,vd ₇ )<30,vd ₆ > 75. The chromatic aberration of the optical system can be better corrected, that is, the chromatic aberration of the optical system can be reduced more effectively to improve the imaging quality of the optical system.

1.7<(nd ₁ ,nd ₃ ,nd ₄ )<2,1.4<(nd ₂ ,nd ₅ ,nd ₆ ,nd ₇ )<1.7 (3)

In expression (3), nd ₁ , nd ₂ , nd ₃ , nd ₄ , nd ₅ , nd ₆ , and nd ₇ are the first lens 101, the second lens 102, the third lens 103, the fourth lens 104, The refractive indices of the fifth lens 105, the sixth lens 106, and the seventh lens 107.

In particular, the third lens 103 and the sixth lens 106 in the optical system 100 satisfy the following expressions: nd ₃ >1.85 and nd ₆ <1.55. The chromatic aberration of the optical system can be reduced more effectively to improve the imaging quality of the optical system.

It can be understood that the optical system 100 can satisfy expression (2) and expression (3) at the same time, and the imaging quality of the optical system can be further improved. In particular, the following expressions are satisfied: 0<(vd ₂ ,vd ₅ ,vd ₇ )<30, vd ₆ >75, nd ₃ >1.85, nd ₆ <1.55, the chromatic aberration of the optical system can be corrected to improve the optical The imaging quality of the system.

In order to further improve the imaging quality of the optical system, the first lens 101 in the optical system 100 satisfies the following expression:

0.4<|D ₁ /R ₁ |<1, 2<|D ₁ /R ₂ |<3.6 (4)

In the expression (4), D ₁ is the diameter of the first lens 101, R ₁ is the curvature radius of the lens surface of the first lens 101 close to the object side, and R ₂ is the curvature of the lens surface of the first lens 101 close to the image side radius. Through the limitation of expression (4), it helps to correct the distortion of the optical system, reduce the ghost image caused by the side surface of the lens is too concave, and also help to improve the resolution of the edge field of view, thereby improving the imaging quality of the optical system.

In some embodiments, in order to miniaturize and lighten the optical system, the optical system is further limited, that is, the optical system 100 satisfies the following expression:

0.75<|T ₁ /T ₂ |<1.25, 0.02<|T ₂ /TL|<0.055, _{0.04<|T 3} /TL|<0.07, _{0.05<|(T 3} +T ₄ )/TL|<0.15, 1<|T ₃ /T ₄ |<2, 0.01<|T ₅ _{/TL|<0.03, 0.02<|(T 6} +T ₇ )/TL|<0.15, 3.5 _{<|T 6} /T ₇ |<4.5 _{_{, 0.1 <| A 1 /TL|<0.25,0.12<|(A 1}} + A 2) / TL | <0.25,0.125 <| A 3 /TL|<0.2,0.02<|A 4 /TL|<0.04, 0.25<|(A ₄ +A ₅ )/TL|<0.4, 0.035<|A ₆ /TL|<0.06; (5)

In the expression (5), TL is the distance on the optical axis from the center vertex of the lens surface of the first lens 101 close to the object side to the imaging surface, and T ₁ to T ₇ are the first lens 101, the second lens 102, and the first lens 101, respectively. The center thickness of the three lenses 103, the fourth lens 104, the fifth lens 105, the sixth lens 106, and the seventh lens 107; A ₁ is the interval between the first lens 101 and the second lens 102, and A ₂ is the second lens The interval between 102 and the third lens 103, A ₃ is the interval between the third lens 103 and the fourth lens 104, A ₄ is the interval between the fourth lens 104 and the fifth lens 105, A ₅ is the fifth lens The interval between the lens 105 and the sixth lens 106, A ₆ is the interval between the sixth lens 106 and the seventh lens 107.

In particular, the limitation of 0.125<|A ₃ /TL|<0.2 helps to realize the mechanical structure of the iris diaphragm of the optical system; _{the limitation of 0.035<|A 6} /TL|<0.06 helps the group of internal focusing systems The realization of the mechanical structure facilitates the structural design of the optical system.

In some embodiments, as shown in FIG. 3, the optical system may further include an infrared lens (IR lens) 108, which is disposed between the seventh lens 107 and the imaging surface I, specifically, it may be close to the imaging surface I. set up. As a result, the optical system can be applied to infrared imaging.

In one embodiment, for further correction, the two mirror surfaces or aspheric lens surfaces of the aforementioned aspheric lens are both high-order aspheric surfaces, and the high-order aspheric surface is adopted to satisfy the following expression:

In the expression (6), z is the aspheric rotational symmetry axis, c is the curvature of the vertex; _y is the radial coordinate, and its unit is the same as the unit length of the lens; k is the conic constant, and a ₁ to a ₈ represent each The coefficient corresponding to the radial coordinate.

The specific numerical configuration of the optical system is given below in conjunction with the drawings and tables. As shown in Figure 2, the

surface numbers

1, 2,..., 15 represent the surface numbers in the optical system, and represent the first lens 101 and the second lens 101, respectively. Lens 102,..., the mirror surface of the seventh lens 107.

Specifically, as shown in FIG. 2, the two lens surfaces of the first lens 101 are surface 1 and surface 2, and the two lens surfaces of the second lens 102 are surface 3 and surface 4, and the two lens surfaces of the third lens 103 respectively. The lens surfaces are surface 5 and surface 6, the aperture stop S is surface 7, the two lens surfaces of the fourth lens 104 are surface 8 and surface 9, and the two lens surfaces of the fifth lens 105 are surface 10 and surface respectively. 11. The two lens surfaces of the sixth lens 106 are surface 12 and surface 13, respectively, and the two lens surfaces of the seventh lens 107 are surface 14 and surface 15 respectively.

In Tables 1 to 3, the radius of curvature represents the degree of curvature of the lens surface, which can be represented by R. The smaller the value of R, the more curved the lens surface; the interval or thickness (Thickness), the interval is expressed as the distance between the lenses of the optical system. The separation distance on the axis, the thickness is the center thickness of the lens; Nd represents the refractive index of the lens; Vd represents the dispersion coefficient of the lens, also known as the Abbe coefficient; “Infinity” represents the plane; “Air” represents the air; “A(13 )” represents the distance between the 13th surface, and “A(15)” represents the distance between the 15th surface. Taking A(15) as an example, it specifically represents the air gap before and after the seventh lens 107, which serves as the inner focusing lens. , At different object distances (infinity and closest), the focusing amount is different, so the air gap value of the 13th surface and the 15th surface are different. k is a conic constant, and a ₁ to a ₈ respectively represent the coefficients corresponding to each radial coordinate. Table 3 shows the corresponding focal length, image-side F number (aperture F number), field of view (FOV), and the amount of change in the movement of the inner focus group when focusing from the infinite object distance to the closest distance. The movement of the inner focus group The amount of change is AC(13) and AC(15).

Table 1 shows the surface parameter data of the optical system

Table 2 shows the aspheric coefficient data of each surface of the optical system

Table 3 shows the configuration data of the optical system lens group

To	无限远Infinity	最近recent
focal lengthfocal length	6.22mm6.22mm	To
FNOFNO	2.472.47	2.492.49
FOVFOV	117.2°117.2°	117.4°117.4°
AC(13)AC(13)	1.1921.192	1.3671.367
AC(15)AC(15)	5.8635.863	5.6885.688

At the same time, through the optical system of the foregoing embodiment, it can be seen that the optical system provided by the present application has the following advantages:

(1) The optical system provided by the present application has a compact structure and adopts a structure that positions the diaphragm as close to the object side as possible, so that the total length of the optical system is shortened, that is, the total length of the entire inner focusing optical system (the first lens 101 is close to the object side). The distance from the apex of the lens surface to the imaging surface) is less than 29mm, and the lens system of the entire optical system (the distance from the apex of the first lens 101 near the object side to the apex of the seventh lens 107 near the image side) is less than 23mm. Improved the miniaturization, light weight and portability of the optical system;

(2) The air gap at the position of the aperture stop S of the optical system provided by this application is greater than 4mm, which helps to realize the mechanical structure of the iris diaphragm;

(3) The air distance between the center vertex of the lens surface of the seventh lens near the image side and the imaging surface of the seventh lens of the optical system provided by this application is greater than 5.6mm, which helps to reduce the influence of dust on the imaging quality, and at the same time facilitates interchangeability. Realization of the mechanical structure of the lens;

(4) The optical system provided by this application uses a single lens or two cemented lenses for internal focusing as the focusing method, so that the overall focusing weight of the system is lighter (the focusing group weight is less than 0.2g) and the focusing speed is faster , And good performance can also be obtained when shooting at close range;

(5) The focusing amount of the optical system provided by this application is small, and the overall focusing amount is less than 0.5mm, so that the breathing effect of the system is small (the change in the field of view of the picture is less than 1°);

(6) The optical system provided in this application can achieve a wide range of system shooting, clear imaging, and can achieve shooting at different object distances from 0.3m to infinity; the peripheral brightness ratio is improved during design; even when the aperture is fully opened, The peripheral brightness ratio is also more than 30%, and the light passing through the entire lens appears more evenly on the screen, effectively avoiding the problem of lens vignetting; FOV is greater than 115°, and the shooting field of view is larger;

(7) The optical system provided by this application, through the combination of glass and plastic aspherical lenses, can achieve an imaging effect with a large image area (φ16mm), high image quality, and high resolution greater than 20M (20 million pixels).

It should be noted that, as shown in FIG. 4, the optical system 100 of the present application further includes a housing 110, in which a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, and a Both the six lens 106 and the seventh lens 107 are installed in the housing 110. Among them, it also includes an adjustment mechanism for achieving internal focusing.

In addition, as shown in FIG. 5, the housing 110 of the optical system 100 may also have a threaded hole 111 through which the optical system 100 can be fixed to the lens of the shooting device, thereby realizing the interchangeability of the optical system.

Please refer to FIG. 6. FIG. 6 is a schematic structural diagram of a photographing device provided by an embodiment of the present application. The camera uses an interchangeable optical system to increase the angle of view to achieve a large image surface and high-quality imaging effects.

As shown in FIG. 6, the photographing apparatus 200 includes an optical system 100 and a photographing device 21, and the optical system 100 adopts any optical system provided in the above-mentioned embodiments.

The photographing device 200 is an electronic device capable of photographing, including a mobile phone, a digital camera, a sports camera, a wearable device, or a handheld pan-tilt camera.

Wherein, the optical system 100 and the photographing device 21 are detachably connected or fixedly connected. The detachable connection is convenient for users to use.

Exemplarily, the optical system 100 and the photographing device 21 are fixed by one or more of magnetic attraction, pasting, screwing, or buckle.

Taking magnetic attraction as an example, when the optical system 100 and the photographing device 21 are fixed by magnetic attraction, the optical system 100 and the photographing device 21 are connected by a magnet male and female pair of attraction. Specifically, a magnet may be installed on the optical system 100 , And the corresponding position of the photographing device 21 is equipped with opposite magnetic poles or metal parts that can be attracted by the magnet. The reverse is also true. The magnet can also be installed on the photographing device 21. In this case, the optical system 10 is equipped with opposite magnetic poles or metal parts that can be attracted by the magnet. Through the above arrangement, the user can easily install and blindly operate, and at the same time avoid the problem of interface wear that is prone to frequent installation and removal.

As shown in FIG. 6, the shooting device 21 is a sports camera, and includes a lens group 210, a display screen 211 and a shooting button 212. The lens group 210 is used to image the scene on the sensor of the shooting device 21, such as a COMS sensor or a CCD sensor; the display screen 211 is used to display imaging, and the display screen 211 is a touch screen; the shooting button 212 is used to trigger shooting.

The photographing device 21 includes a lens group 210, and the seventh lens 107 of the optical system 100 is kept at a certain distance from the outermost lens of the lens group 210. For example, it is larger than 6mm to connect the optical system and the shooting device 21 to ensure that there is no direct contact between the two and improve safety.

In one embodiment, the optical system 100 matches the lens parameters of the photographing device 21. In turn, the image quality is improved.

Exemplarily, the lens parameters of the optical system 100 include: aperture, aperture, and image plane, etc., wherein the aperture and aperture of the optical system 100 are consistent with those of the shooting device, thereby ensuring the consistency of the image quality of the overall system. sex.

In an embodiment, the lens parameters include an image surface, and the image surface is larger than 16 mm. Furthermore, the large image plane imaging is realized through the setting of the above-mentioned optical system itself or the cooperation with the photographing equipment. In turn, the problem of the small imaging surface of the existing imaging device is solved.

In one embodiment, by using the optical system 100, the field of view of the photographing device 200 can be greater than 115°. This achieves a large shooting range and clear imaging.

In one embodiment, the diameters of the first lens 101 to the seventh lens 107 of the optical system 100 are all larger than the lens diameter of the photographing device 21. As a result, large image plane imaging can be realized, which in turn solves the problems that the imaging surface of the existing imaging device is small, mostly smaller than the image plane with a diameter of 16 mm, and the resolution is low and the image quality is poor.

Since the photographing device in the foregoing embodiment uses the optical system provided in the embodiment of the present application, the angle of view of the photographing device can be increased, and the imaging quality of the photographing device can be improved at the same time.

Please refer to FIG. 7, which is a schematic structural diagram of a movable platform provided by an embodiment of the present application. The movable platform is equipped with a shooting device to realize shooting.

As shown in FIG. 7, the movable platform 300 includes a platform body 310 and a photographing device 200. The photographing device 200 is installed on the platform body 310. The photographing device 200 includes an optical system 100 and a photographing device 21. The optical system 100 is connected to the photographing device 21. The optical system 100 adopts any optical system provided in the above-mentioned embodiments.

Exemplarily, the movable platform 300 includes an aircraft, a robot, or a handheld pan/tilt.

Among them, the aircraft includes drones, which include rotary-wing drones, such as four-rotor drones, hexa-rotor drones, and octo-rotor drones. It can also be a fixed-wing drone or It is a combination of rotary-wing and fixed-wing drones, and is not limited here.

Among them, the robot can also be called an educational robot. It uses a Mecanum wheel omnidirectional chassis and is equipped with multiple pieces of intelligent armor. Each intelligent armor has a built-in impact detection module that can quickly detect physical strikes. At the same time, it also includes a two-axis pan/tilt, which can be flexibly rotated, matched with the transmitter to accurately, stably and continuously fire crystal bombs or infrared beams, and matched with ballistic light effects, giving users a more realistic shooting experience.

For example, if the optical system is installed on an unmanned aerial vehicle, the optical system can increase the angle of view of the lens, and then can shoot a larger range of scenes, while improving the imaging quality of the shooting device, and the combination of multiple lenses makes it relatively The distance is small, thereby reducing the volume of the optical system, achieving miniaturization and portability. Therefore, when the drone is used for aerial photography, better images can be taken by using the optical system, thereby improving the user experience.

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Anyone familiar with the technical field can easily think of various equivalents within the technical scope disclosed in this application. Modifications or replacements, these modifications or replacements shall be covered within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

An optical system, characterized in that the optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in order from the object side to the image side , The first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power, and the third lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

1.5<|f 1 /f|<2.5, 4 <|(f 2 +f 1 )/f|<6, 1<|f 3 /f|<2, 1<|f 4 /f|<2, 0.9 <| f 5 /f|<1.5,0.9<|f 5 / f 6 | <1.5,4.5 <| f 7 / f 6 | <6,4.5 <| f 7 / f | <6,4 <| TL / f|<5, 0.2<|BFL/TL|<0.5;

Where f is the focal length of the optical system, f 1 is the focal length of the first lens, f 2 is the focal length of the second lens, f 3 is the focal length of the third lens, and f 4 is the first lens. The focal length of the four lenses, f 5 is the focal length of the fifth lens, f 6 is the focal length of the sixth lens, f 7 is the focal length of the seventh lens, and TL is the lens near the object side of the first lens The distance on the optical axis from the surface center to the imaging surface; BFL is the distance on the optical axis from the center of the lens surface of the seventh lens near the image side to the imaging surface.
The optical system according to claim 1, wherein the optical system includes at least one lens made of glass; and/or, the optical system includes at least one lens made of plastic.
The optical system according to claim 1, wherein at least one of the second lens, the fifth lens, and the seventh lens is a plastic lens.
The optical system according to claim 1, wherein at least one lens in the optical system is an aspheric lens.
The optical system according to claim 1, wherein at least one of the two lens surfaces of the second lens, the fifth lens, the sixth lens or the seventh lens is aspherical.
The optical system according to claim 1, wherein the third lens and the fourth lens are located on both sides of an aperture stop of the optical system.
The optical system according to claim 6, wherein the distance between the positions of the aperture diaphragm of the optical system is greater than 4mm, and the distance between the positions is two adjacent to the aperture diaphragm. The distance between the two lenses.
The optical system according to claim 1, wherein the distance from the center vertex of the lens surface of the seventh lens near the image side to the imaging surface is greater than a predetermined distance.
The optical system according to claim 8, wherein the preset distance includes 5.6 mm.
The optical system according to claim 1, wherein at least one of the second lens to the seventh lens of the optical system can be used as an internal focusing lens group.
10. The optical system according to claim 10, wherein the distance between the focusing lens and the adjacent lens during internal focusing is at least greater than 1.1 mm.
The optical system according to claim 10, wherein the weight of the focus group of the optical system is less than 0.2g; and/or, during internal focusing, the adjustment amount corresponding to the internal focus lens group is less than 0.5mm.
The optical system according to claim 10, wherein the field of view of the optical system is greater than 115°; and/or, the change of the field of view of the optical system is less than 0.5°.
The optical system according to claim 10, wherein the optical system further comprises an infrared lens, and the infrared lens is disposed between the seventh lens and the imaging surface.
The optical system according to claim 1, wherein the optical system satisfies the following expression:

(vd 1 ,vd 4 ,vd 6 )>40,0<(vd 2 ,vd 3 ,vd 5 ,vd 7 )<40

Wherein, vd 1 , vd 2 , vd 3 , vd 4 , vd 5 , vd 6 , vd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, Dispersion coefficient of the seventh lens.
The optical system according to claim 15, wherein the second lens, the fifth lens, the sixth lens, and the seventh lens satisfy the following expression: 0<(vd 2 ,vd 5 ,vd 7 )<30 , Vd 6 >75.
The optical system according to claim 15 or 16, wherein the optical system satisfies the following expression:

1.7<(nd 1 ,nd 3 ,nd 4 )<2,1.4<(nd 2 ,nd 5 ,nd 6 ,nd 7 )<1.7

Wherein, nd 1 , nd 2 , nd 3 , nd 4 , nd 5 , nd 6 , and nd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, The refractive index of the seventh lens.
The optical system according to claim 17, wherein the third lens and the sixth lens satisfy the following expressions: nd 3 > 1.85 and nd 6 <1.55.
The optical system according to any one of claims 1 to 14, wherein the first lens satisfies the following expression:

0.4<|D 1 /R 1 |<1, 2<|D 1 /R 2 |<3.6

Wherein, D 1 is the diameter of the first lens, R 1 is the radius of curvature of the lens surface of the first lens close to the object side, and R 2 is the radius of curvature of the lens surface of the first lens close to the image side.
The optical system according to any one of claims 1 to 14, wherein the optical system satisfies the following expression:

0.75<|T 1 /T 2 |<1.25, 0.02<|T 2 /TL|<0.055, 0.04<|T 3 /TL|<0.07, 0.05<|(T 3 +T 4 )/TL|<0.15, 1<|T 3 /T 4 |<2, 0.01<|T 5 /TL|<0.03, 0.02<|(T 6 +T 7 )/TL|<0.15, 3.5 <|T 6 /T 7 |<4.5 , 0.1 <| A 1 /TL|<0.25,0.12<|(A 1 + A 2) / TL | <0.25,0.125 <| A 3 /TL|<0.2,0.02<|A 4 /TL|<0.04, 0.25<|(A 4 +A 5 )/TL|<0.4, 0.035<|A 6 /TL|<0.06;

Wherein, TL is the distance on the optical axis from the center vertex of the lens surface of the first lens close to the object side to the imaging surface, and T 1 to T 7 are the first lens, the second lens, the third lens, and the first lens, respectively. The center thickness of the four lenses, the fifth lens, the sixth lens, and the seventh lens; A 1 is the distance between the first lens and the second lens, and A 2 is the second lens and the third lens. The interval between the lenses, A 3 is the interval between the third lens and the fourth lens, A 4 is the interval between the fourth lens and the fifth lens, and A 5 is the interval between the fourth lens and the fourth lens. The interval between the fifth lens and the sixth lens, A 6 is the interval between the sixth lens and the seventh lens.
The optical system according to claim 1, wherein the total length of the optical system is less than 29mm; and/or the length of the lens system of the optical system is less than 23mm, and the lens system is the object side of the first lens The distance from the vertex of the seventh lens to the vertex of the image side of the seventh lens.
A photographing device, characterized in that the photographing device includes an optical system and a photographing device, the optical system is connected to the photographing device, and the optical system includes a first lens and a second lens arranged in sequence from the object side to the image side. The second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens, the first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power, and the third lens The lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

1.5<|f 1 /f|<2.5, 4 <|(f 2 +f 1 )/f|<6, 1<|f 3 /f|<2, 1<|f 4 /f|<2, 0.9 <| f 5 /f|<1.5,0.9<|f 5 / f 6 | <1.5,4.5 <| f 7 / f 6 | <6,4.5 <| f 7 / f | <6,4 <| TL / f|<5, 0.2<|BFL/TL|<0.5;

Where f is the focal length of the optical system, f 1 is the focal length of the first lens, f 2 is the focal length of the second lens, f 3 is the focal length of the third lens, and f 4 is the first lens. The focal length of the four lenses, f 5 is the focal length of the fifth lens, f 6 is the focal length of the sixth lens, f 7 is the focal length of the seventh lens, and TL is the lens near the object side of the first lens The distance on the optical axis from the surface center to the imaging surface; BFL is the distance on the optical axis from the center of the lens surface of the seventh lens near the image side to the imaging surface.
The photographing device according to claim 22, wherein the optical system includes at least one lens made of glass; and/or, the optical system includes at least one lens made of plastic.
The photographing device according to claim 22, wherein at least one of the second lens, the fifth lens, and the seventh lens is a plastic lens.
The photographing device according to claim 22, wherein at least one lens in the optical system is an aspheric lens.
The photographing device according to claim 22, wherein at least one of the two lens surfaces of the second lens, the fifth lens, the sixth lens or the seventh lens is aspherical.
The photographing device according to claim 22, wherein the third lens and the fourth lens are located on both sides of an aperture stop of the optical system.
The photographing device according to claim 27, wherein the distance between the positions of the aperture diaphragm of the optical system is greater than 4 mm, wherein the distance between the positions is two adjacent to the aperture diaphragm. The distance between the two lenses.
The photographing device according to claim 22, wherein the distance from the center vertex of the lens surface of the seventh lens near the image side to the imaging surface is greater than a predetermined distance.
The photographing device according to claim 29, wherein the preset distance comprises 5.6 mm.
The photographing device according to claim 22, wherein at least one of the second lens to the seventh lens of the optical system can be used as an internal focusing lens group.
The photographing device according to claim 31, wherein the distance between the focusing lens and the adjacent lens during internal focusing is at least greater than 1.1 mm.
The photographing device according to claim 31, wherein, during internal focusing, the adjustment amount corresponding to the internal focusing lens group is less than 0.5 mm; and/or the focus group weight of the optical system is less than 0.2 g.
The photographing device according to claim 31, wherein the field of view of the optical system is greater than 115°; and/or the change of the field of view of the optical system is less than 0.5°.
The photographing device according to claim 31, wherein the optical system further comprises an infrared lens, and the infrared lens is disposed between the seventh lens and the imaging surface.
The photographing device according to claim 22, wherein the optical system satisfies the following expression:

(vd 1 ,vd 4 ,vd 6 )>40,0<(vd 2 ,vd 3 ,vd 5 ,vd 7 )<40

Wherein, vd 1 , vd 2 , vd 3 , vd 4 , vd 5 , vd 6 , vd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, Dispersion coefficient of the seventh lens.
The photographing device according to claim 36, wherein the second lens, the fifth lens, the sixth lens, and the seventh lens satisfy the following expression: 0<(vd 2 ,vd 5 ,vd 7 )<30 , Vd 6 >75.
The photographing device according to claim 36 or 37, wherein the optical system satisfies the following expression:

1.7<(nd 1 ,nd 3 ,nd 4 )<2,1.4<(nd 2 ,nd 5 ,nd 6 ,nd 7 )<1.7

Wherein, nd 1 , nd 2 , nd 3 , nd 4 , nd 5 , nd 6 , and nd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, The refractive index of the seventh lens.
The photographing device according to claim 38, wherein the third lens and the sixth lens satisfy the following expressions: nd 3 > 1.85 and nd 6 <1.55.
The photographing device according to any one of claims 22 to 35, wherein the first lens satisfies the following expression:

0.4<|D 1 /R 1 |<1, 2<|D 1 /R 2 |<3.6

Wherein, D 1 is the diameter of the first lens, R 1 is the radius of curvature of the lens surface of the first lens close to the object side, and R 2 is the radius of curvature of the lens surface of the first lens close to the image side.
The photographing device according to any one of claims 22 to 35, wherein the optical system satisfies the following expression:

0.75<|T 1 /T 2 |<1.25, 0.02<|T 2 /TL|<0.055, 0.04<|T 3 /TL|<0.07, 0.05<|(T 3 +T 4 )/TL|<0.15, 1<|T 3 /T 4 |<2, 0.01<|T 5 /TL|<0.03, 0.02<|(T 6 +T 7 )/TL|<0.15, 3.5 <|T 6 /T 7 |<4.5 , 0.1 <| A 1 /TL|<0.25,0.12<|(A 1 + A 2) / TL | <0.25,0.125 <| A 3 /TL|<0.2,0.02<|A 4 /TL|<0.04, 0.25<|(A 4 +A 5 )/TL|<0.4, 0.035<|A 6 /TL|<0.06;

Wherein, TL is the distance on the optical axis from the center vertex of the lens surface of the first lens close to the object side to the imaging surface, and T 1 to T 7 are the first lens, the second lens, the third lens, and the first lens, respectively. The center thickness of the four lenses, the fifth lens, the sixth lens, and the seventh lens; A 1 is the distance between the first lens and the second lens, and A 2 is the second lens and the third lens. The distance between the lenses, A 3 is the distance between the third lens and the fourth lens, A 4 is the distance between the fourth lens and the fifth lens, and A 5 is the distance between the fourth lens and the fourth lens. The interval between the fifth lens and the sixth lens, A 6 is the interval between the sixth lens and the seventh lens.
The photographing device according to claim 22, wherein the total length of the optical system is less than 29mm; and/or the length of the lens system of the optical system is less than 23mm, and the lens system is the object side of the first lens The distance from the vertex of the seventh lens to the vertex of the image side of the seventh lens.
The photographing device according to claim 22, wherein the optical system and the photographing device are fixedly connected by one or more of magnetic attraction, pasting, threading, or buckle.
A movable platform, wherein the movable platform comprises a platform body and a photographing device, the photographing device is mounted on the platform body; the photographing device comprises an optical system and a photographing device, and the optical system is connected In the photographing device, the optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens that are sequentially arranged from the object side to the image side. The first lens, the second lens, the fifth lens, and the seventh lens have negative refractive power, and the third lens, the fourth lens, and the sixth lens have positive refractive power;

The optical system satisfies the following expression:

1.5<|f 1 /f|<2.5, 4 <|(f 2 +f 1 )/f|<6, 1<|f 3 /f|<2, 1<|f 4 /f|<2, 0.9 <| f 5 /f|<1.5,0.9<|f 5 / f 6 | <1.5,4.5 <| f 7 / f 6 | <6,4.5 <| f 7 / f | <6,4 <| TL / f|<5, 0.2<|BFL/TL|<0.5;

Where f is the focal length of the optical system, f 1 is the focal length of the first lens, f 2 is the focal length of the second lens, f 3 is the focal length of the third lens, and f 4 is the first lens. The focal length of the four lenses, f 5 is the focal length of the fifth lens, f 6 is the focal length of the sixth lens, f 7 is the focal length of the seventh lens, and TL is the lens near the object side of the first lens The distance on the optical axis from the surface center to the imaging surface; BFL is the distance on the optical axis from the center of the lens surface of the seventh lens near the image side to the imaging surface.
The movable platform of claim 44, wherein the optical system includes at least one lens made of glass; and/or, the optical system includes at least one lens made of plastic.
The movable platform of claim 44, wherein at least one of the second lens, the fifth lens, and the seventh lens is a lens made of plastic material.
The movable platform of claim 44, wherein at least one lens in the optical system is an aspheric lens.
The movable platform according to claim 44, wherein at least one of the two lens surfaces of the second lens, the fifth lens, the sixth lens or the seventh lens is aspherical.
The movable platform according to claim 44, wherein the third lens and the fourth lens are located on both sides of the aperture stop of the optical system.
The movable platform according to claim 49, wherein the distance between the positions of the aperture diaphragm of the optical system is greater than 4mm, wherein the distance between the positions is adjacent to the aperture diaphragm The distance between the two lenses.
The movable platform of claim 44, wherein the distance from the center vertex of the lens surface of the seventh lens near the image side to the imaging surface is greater than a preset distance.
The movable platform of claim 51, wherein the preset distance includes 5.6 mm.
44. The movable platform of claim 44, wherein at least one of the second lens to the seventh lens of the optical system can be used as an internal focusing lens group.
The movable platform according to claim 53, wherein the distance between the focusing lens and the adjacent lens during internal focusing is at least greater than 1.1 mm.
The movable platform according to claim 53, wherein, during internal focusing, the adjustment amount corresponding to the internal focusing lens group is less than 0.5 mm; and/or the focus group weight of the optical system is less than 0.2 g.
The movable platform according to claim 53, wherein the field of view of the optical system is greater than 115°; and/or the change of the field of view of the optical system is less than 0.5°.
The movable platform according to claim 53, wherein the optical system further comprises an infrared lens, and the infrared lens is disposed between the seventh lens and the imaging surface.
The movable platform according to claim 44, wherein the optical system satisfies the following expression:

(vd 1 ,vd 4 ,vd 6 )>40,0<(vd 2 ,vd 3 ,vd 5 ,vd 7 )<40

Wherein, vd 1 , vd 2 , vd 3 , vd 4 , vd 5 , vd 6 , vd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, Dispersion coefficient of the seventh lens.
The movable platform according to claim 58, wherein the second lens, the fifth lens, the sixth lens and the seventh lens satisfy the following expression: 0<(vd 2 ,vd 5 ,vd 7 )< 30, vd 6 >75.
The movable platform according to claim 58 or 59, wherein the optical system satisfies the following expression:

1.7<(nd 1 ,nd 3 ,nd 4 )<2,1.4<(nd 2 ,nd 5 ,nd 6 ,nd 7 )<1.7

Wherein, nd 1 , nd 2 , nd 3 , nd 4 , nd 5 , nd 6 , and nd 7 are the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, The refractive index of the seventh lens.
The movable platform according to claim 60, wherein the third lens and the sixth lens satisfy the following expressions: nd 3 > 1.85 and nd 6 <1.55.
The movable platform according to any one of claims 44 to 57, wherein the first lens satisfies the following expression:

0.4<|D 1 /R 1 |<1, 2<|D 1 /R 2 |<3.6

Wherein, D 1 is the diameter of the first lens, R 1 is the radius of curvature of the lens surface of the first lens close to the object side, and R 2 is the radius of curvature of the lens surface of the first lens close to the image side.
The movable platform according to any one of claims 44 to 57, wherein the optical system satisfies the following expression:

0.75<|T 1 /T 2 |<1.25, 0.02<|T 2 /TL|<0.055, 0.04<|T 3 /TL|<0.07, 0.05<|(T 3 +T 4 )/TL|<0.15, 1<|T 3 /T 4 |<2, 0.01<|T 5 /TL|<0.03, 0.02<|(T 6 +T 7 )/TL|<0.15, 3.5 <|T 6 /T 7 |<4.5 , 0.1 <| A 1 /TL|<0.25,0.12<|(A 1 + A 2) / TL | <0.25,0.125 <| A 3 /TL|<0.2,0.02<|A 4 /TL|<0.04, 0.25<|(A 4 +A 5 )/TL|<0.4, 0.035<|A 6 /TL|<0.06;

Wherein, TL is the distance on the optical axis from the center vertex of the lens surface of the first lens close to the object side to the imaging surface, and T 1 to T 7 are the first lens, the second lens, the third lens, and the first lens, respectively. The center thickness of the four lenses, the fifth lens, the sixth lens, and the seventh lens; A 1 is the distance between the first lens and the second lens, and A 2 is the second lens and the third lens. The interval between the lenses, A 3 is the interval between the third lens and the fourth lens, A 4 is the interval between the fourth lens and the fifth lens, and A 5 is the interval between the fourth lens and the fourth lens. The interval between the fifth lens and the sixth lens, A 6 is the interval between the sixth lens and the seventh lens.
The movable platform according to claim 44, wherein the total length of the optical system is less than 29mm; and/or the length of the lens system of the optical system is less than 23mm, and the lens system is the first lens object. The distance from the vertex of the side surface to the vertex of the seventh lens image side surface.
The movable platform according to claim 44, wherein the optical system and the photographing device are fixedly connected by one or more of magnetic attraction, pasting, threading, or buckle.