CN114185148A

CN114185148A - Lens assembly and mobile terminal

Info

Publication number: CN114185148A
Application number: CN202010858029.9A
Authority: CN
Inventors: 尹志东
Original assignee: Beijing Xiaomi Mobile Software Co Ltd
Current assignee: Beijing Xiaomi Mobile Software Co Ltd
Priority date: 2020-08-24
Filing date: 2020-08-24
Publication date: 2022-03-15

Abstract

The invention relates to a lens assembly and a mobile terminal, wherein the lens assembly comprises: a lens group including a plurality of lenses; the photosensitive element is positioned on the optical axis of the lens group and comprises an imaging surface; the lens assembly determines lens parameters and aspheric coefficients of the plurality of lenses based on at least one of the following three conditional expressions: 1.16< EFL/IMH < 1.3; 1.3< TTL/TL < 1.7; 1.2< EFL/TL < 1.45; wherein EFL is an effective focal length of the lens assembly; IMH is half of the diagonal dimension of the imaging surface of the photosensitive element; TL is the distance from the object side surface to the image side surface of each lens in the lens group, which is closest to the most protruding position of the photosensitive element and is along the optical axis direction; TTL is the distance between the object side surface of the lens closest to the object side in the lens group and the imaging surface of the photosensitive element on the optical axis. The lens assembly of the invention can shorten the thickness of each lens in the lens group and the distance between the lenses on the premise of ensuring the optical performance, thereby shortening the thickness of the lens body.

Description

Lens assembly and mobile terminal

Technical Field

The invention relates to the technical field of electronic equipment, in particular to a lens assembly and a mobile terminal.

Background

With the continuous updating of the specifications of consumer electronics products, especially mobile electronic devices such as Smart phones (Smart phones), the step of pursuing miniaturization has never been stopped, and the most important characteristics for optical imaging lenses are still the imaging quality and volume.

In the related art, in order to realize ultra-thinning of a smart phone, an optical imaging lens is developed towards miniaturization, and the number of lenses is generally reduced to compress the volume of the optical imaging lens, so that the imaging quality is reduced. How to take both the imaging quality and the miniaturization of the optical imaging lens into consideration is a problem to be considered.

Disclosure of Invention

In order to overcome the problems in the related art, the invention provides a lens assembly and a mobile terminal.

According to a first aspect of embodiments of the present invention, there is provided a lens assembly including: a lens group including a plurality of lenses; the photosensitive element is positioned on the optical axis of the lens group and comprises an imaging surface; the lens component determines lens parameters and aspheric coefficients of the plurality of lenses based on at least one of the following three conditional expressions: 1.16< EFL/IMH < 1.3; 1.3< TTL/TL < 1.7; 1.2< EFL/TL < 1.45; wherein EFL is an effective focal length of the lens assembly; IMH is half the diagonal dimension of the imaging surface of the photosensitive element; TL is the distance from the object side surface to the image side surface of each lens in the lens group, which is closest to the most protruding position of the photosensitive element and is along the optical axis direction; TTL is a distance from an object-side surface of a lens closest to the object side in the lens group to the image plane of the photosensitive element on the optical axis.

In an embodiment, the lens assembly includes eight aspheric lens elements, and the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, the sixth lens element, the seventh lens element and the eighth lens element are disposed sequentially from an object side to an image side.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the gaps between the eight aspheric lenses and/or the thickness of each lens.

In one embodiment, the gaps and thicknesses between the eight aspheric lenses satisfy the following conditions:

1.2< ALT/AAG < 3.0; wherein ALT is a sum of lens thicknesses of the first lens to the eighth lens; AAG is a sum of seven air gaps between the first lens to the eighth lens.

In one embodiment, the thicknesses of the eight aspheric lenses satisfy the following conditional expression: 2.0< Tmax/Tmin < 4.5;

wherein Tmax is a maximum value of thicknesses of the first lens to the eighth lens, and Tmin is a minimum value of thicknesses of the first lens to the eighth lens.

In one embodiment, the clearance between the eight aspheric lenses satisfies the following conditional expression:

2.6< Gmax/Gmin < 25.0; wherein Gmax is a maximum value of seven air gaps between the first lens to the eighth lens, and Gmin is a minimum value of seven air gaps between the first lens to the eighth lens.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on center thicknesses of the eight aspheric lenses.

In one embodiment, the center thicknesses of the eight aspheric lenses satisfy the following conditional expression:

0.9< (T1+ T6+ T7+ T8)/(T2+ T3+ T4+ T5) < 3; wherein T1 is a center thickness of the first lens, T2 is a center thickness of the second lens, T3 is a center thickness of the third lens, T4 is a center thickness of the fourth lens, T5 is a center thickness of the fifth lens, T6 is a center thickness of the sixth lens, T7 is a center thickness of the seventh lens, and T8 is a center thickness of the eighth lens.

3< (T1+ T2+ T3+ T4+ T5)/T3< 8; wherein T1 is a center thickness of the first lens, T2 is a center thickness of the second lens, T3 is a center thickness of the third lens, T4 is a center thickness of the fourth lens, T5 is a center thickness of the fifth lens, T6 is a center thickness of the sixth lens, T7 is a center thickness of the seventh lens, and T8 is a center thickness of the eighth lens.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the focal lengths of the eight aspheric lenses.

In one embodiment, the focal lengths of the eight aspheric lenses satisfy the following conditional expression:

1.0< | f2/f1| < 4.5; wherein f1 is the focal length of the first lens of the lens assembly, and f2 is the focal length of the second lens of the lens assembly.

0.23< | EFL/f2| + | EFL/f3| < 2.5; wherein f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the optical axis distances of the eight aspheric lenses.

In one embodiment, the optical axis distances of the eight aspheric lenses satisfy the following conditional expression:

1.5<(G23+G34+G56)/(G12+G45+G67+G78)<3.6；

wherein G12 is the distance between the first lens and the second lens on the optical axis, G23 is the distance between the second lens and the third lens on the optical axis, G34 is the distance between the third lens and the fourth lens on the optical axis, G45 is the distance between the fourth lens and the fifth lens on the optical axis, G56 is the distance between the fifth lens and the sixth lens on the optical axis, G67 is the distance between the sixth lens and the seventh lens on the optical axis, and G78 is the distance between the seventh lens and the eighth lens on the optical axis.

4< (G23+ G34+ G56+ OBFL)/(G12+ G45+ G67+ G78) < 14; and the OBFL is the distance from the image side surface of the eighth lens to the imaging surface on the optical axis.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the following conditional expressions:

1.45< TL/EPD < 1.90; wherein EPD is the entrance pupil diameter of the lens assembly.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the following conditional expressions: 16.0< HFOV EPD/EFL < 19.3; wherein the HFOV is a half field angle of the lens assembly.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the following conditional expressions: 2.8< TTL IMH/(EPD AP8) < 3.6; wherein AP8 is the maximum effective radial dimension of the eighth lens.

In one embodiment, the lens parameters and the aspheric coefficients are determined based on an entrance pupil diameter of a lens assembly.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the following conditional expressions: 0.95< ALT/BFL < 1.9; and BFL is the distance from the most salient point of the image side surface of the eighth lens to the image surface along the optical axis direction.

In one embodiment, the lens parameters and the aspheric coefficients of the lenses of the lens group are determined based on the following conditional expressions: 0.58< CP72/CP82< 1.3; wherein CP72 is a distance from a critical point of the image side surface of the seventh lens element to the optical axis, and CP82 is a distance from a critical point of the image side surface of the eighth lens element to the optical axis.

In one embodiment, the lens set can move along the optical axis direction; when the lens assembly works, the distance between the lens group and the imaging surface of the photosensitive element is a first distance; when the lens assembly is in a non-working state, the distance between the lens group and the imaging surface of the photosensitive element is a second distance, and the first distance is greater than the second distance.

In one embodiment, the lens assembly includes: the driving piece is arranged in the terminal body and drives the lens body to move.

In an embodiment, the driving member includes a driving motor disposed in the terminal body, a gear in transmission connection with the driving motor, and a rack engaged with the gear, and the rack is connected with the lens body.

In an embodiment, the driving member includes a driving motor disposed in the terminal body and a screw rod in transmission connection with the driving motor, the screw rod is in threaded connection with the lens body, and the driving motor drives the screw rod to rotate to drive the lens body to move linearly.

In an embodiment, the driving member includes a first electromagnetic component fixed in the terminal body and a second electromagnetic component fixed on the outer wall of the lens body, the first electromagnetic component and the second electromagnetic component are connected with a control circuit of the terminal, and the first electromagnetic component and the second electromagnetic component are controlled to change magnetism to attract or repel each other, so that the lens body moves.

In one embodiment, a color filter is arranged between the photosensitive element and the lens group, and the color filter can move close to or away from the photosensitive element along the optical axis direction; when the lens assembly is in a working state, the distance between the color filter and the imaging surface of the photosensitive element is a third distance; when the lens assembly is in a non-working state, the distance between the color filter and the imaging surface of the photosensitive element is a fourth distance, and the third distance is greater than the fourth distance.

According to a second aspect of the embodiments of the present invention, there is provided a mobile terminal including the lens assembly according to any one of the embodiments of the first aspect.

The technical scheme provided by the embodiment of the invention can have the following beneficial effects:

the lens assembly can shorten the thickness of each lens in the lens group and the distance between the lenses on the premise of ensuring the optical performance, and further can shorten the thickness of the lens body.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a schematic structural diagram of a lens assembly shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 2 is a schematic diagram illustrating an operational state of a lens assembly according to an exemplary embodiment of the present disclosure.

Fig. 3 is a schematic diagram illustrating a lens assembly in a non-operating state according to an exemplary embodiment of the present disclosure.

Fig. 4A is a schematic structural diagram of a lens assembly of the first embodiment shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 4B is a graph of spherical aberration, astigmatism, and distortion of fig. 4A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 5A is a schematic structural diagram of a lens assembly of a second embodiment shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 5B is a graph of spherical aberration, astigmatism, and distortion of fig. 5A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 6A is a schematic structural diagram of a lens assembly according to a third embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 6B is a graph of spherical aberration, astigmatism, and distortion of fig. 6A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 7A is a schematic structural diagram of a lens assembly according to a fourth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 7B is a graph of spherical aberration, astigmatism, and distortion of fig. 7A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 8A is a schematic structural diagram of a lens assembly of a fifth embodiment shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 8B is a graph of spherical aberration, astigmatism, and distortion of fig. 8A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 9A is a schematic structural diagram of a lens assembly according to a sixth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 9B is a graph of spherical aberration, astigmatism, and distortion of fig. 9A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 10A is a schematic structural diagram of a lens assembly according to a seventh embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 10B is a graph of spherical aberration, astigmatism, and distortion of fig. 10A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 11A is a schematic structural diagram of a lens assembly according to an eighth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 11B is a graph of spherical aberration, astigmatism, and distortion of fig. 11A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 12A is a schematic structural diagram of a lens assembly of the ninth embodiment shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 12B is a graph of spherical aberration, astigmatism, and distortion of fig. 12A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 13A is a schematic structural diagram of a lens assembly according to a tenth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 13B is a graph of spherical aberration, astigmatism, and distortion of fig. 13A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 14A is a schematic structural diagram of a lens assembly according to an eleventh embodiment shown in an exemplary embodiment of the present disclosure.

FIG. 14B is a graph illustrating spherical aberration, astigmatism and distortion of FIG. 14A according to an exemplary embodiment of the disclosure

Fig. 15A is a schematic structural diagram of a lens assembly according to a twelfth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 15B is a graph of spherical aberration, astigmatism, and distortion of fig. 15A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 16A is a schematic structural diagram of a lens assembly according to a thirteenth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 16B is a graph of spherical aberration, astigmatism, and distortion of fig. 16A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 17A is a schematic structural diagram of a lens assembly according to a fourteenth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 17B is a graph of spherical aberration, astigmatism, and distortion of fig. 17A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 18A is a schematic structural diagram of a lens assembly according to a fifteenth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 18B is a graph of spherical aberration, astigmatism, and distortion of fig. 18A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 19A is a schematic structural diagram of a lens assembly according to a sixteenth embodiment shown in an exemplary embodiment of the present disclosure.

Fig. 19B is a graph of spherical aberration, astigmatism, and distortion of fig. 19A shown in accordance with an exemplary embodiment of the present disclosure.

Fig. 20 is a schematic structural diagram of a mobile terminal shown according to an exemplary embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the invention, as detailed in the appended claims.

The embodiment of the disclosure provides a lens assembly which can be applied to a mobile terminal. The mobile terminal can be a portable electronic device such as a smart phone, a tablet computer, a notebook computer and the like.

Fig. 1 is a schematic structural diagram of a lens assembly shown in accordance with an exemplary embodiment of the present disclosure. As shown in fig. 1, the lens assembly 1 includes a lens group 10 and a light sensing element 200.

The lens group 10 includes a plurality of lenses, and the photosensitive element 200 is located on an optical axis of the lens group 10 and includes an image plane; the lens assembly 1 determines lens parameters and aspheric coefficients of the lenses of the lens group based on at least one of the following three conditional expressions: 1.16< EFL/IMH < 1.3; 1.3< TTL/TL < 1.7; 1.2< EFL/TL < 1.45; that is, optionally one or more of the three conditional expressions are used to determine the lens parameters and the aspheric coefficients of the lenses of the lens group.

Wherein, the EFL is the effective focal length of the lens component 1; IMH is half the diagonal dimension of the imaging surface of the photosensitive element 200; TL is a distance in the optical axis direction from the object-side surface of each lens in the lens group 10 to the most protruded position where the image-side surface is closest to the photosensitive element 200; TTL is the distance between the object-side surface of the lens element closest to the object side in the lens group 10 and the image plane of the photosensitive element 200 on the optical axis. The photosensitive element 200 is a photosensitive chip.

According to the present disclosure, parameters of the lens and aspheric coefficients of the lenses are determined according to the above conditional expressions, and on the premise of ensuring optical performance, the thickness of each lens in the lens group 10 and the distance between the lenses can be reduced, and further, the thickness of the lens body can be reduced, such that when the lens is applied to a mobile terminal (e.g., a mobile phone), the thinning of the mobile terminal is facilitated. In addition, since the overall thickness of the lens assembly 10 is reduced, the light from the object to be photographed is refracted and adjusted by the lens in the lens assembly 10, and then the area projected onto the surface of the photosensitive element 200 is increased, so that the size of the photosensitive surface of the photosensitive element 200 can be increased, and the imaging quality is higher.

In one embodiment, the lens group 10 includes eight aspheric lens elements, in order from an object side to an image side, the first lens element 110, the second lens element 120, the third lens element 130, the fourth lens element 140, the fifth lens element 150, the sixth lens element 160, the seventh lens element 170 and the eighth lens element 180. Wherein each lens comprises an object side surface and an image side surface, i.e. the first lens 110 comprises a first object side surface 111 and a first image side surface 112; the second lens 120 includes a second object side surface 121 and a second image side surface 122; third lens 130 includes a third object side 131 and a third image side 132; the fourth lens 140 includes a fourth object side surface 141 and a fourth image side surface 142; fifth lens 150 includes a fifth object side surface 151 and a fifth image side surface 152; sixth lens 160 includes a sixth object side surface 161 and a sixth image side surface 162; seventh lens 170 includes a seventh object side surface 171 and a seventh image side surface 172; the eighth lens 180 includes an eighth object side surface 181 and an eighth image side surface 182.

The eight aspheric lenses are made of plastic materials, can form high-precision aspheric surfaces, have more control variables compared with the spherical surface, and are used for reducing aberration, so that the number of lenses required by the traditional spherical surface can be reduced, and the total optical length can be effectively reduced.

Further, in the lens assembly 1 of the present disclosure, all of the object-

side surfaces

111, 121, 131, 141, 151, 161, 171, 181 and the image-

side surfaces

112, 122, 132, 142, 152, 162, 172, 182 of the first lens 110 to the eighth lens 180 total 16 aspheric surfaces, which are of a Qbfs type and whose surface-type formula is defined by the following formula:

wherein z represents the depth of the aspheric surface (the point on the aspheric surface that is Y from the optical axis, the perpendicular distance between the point and the tangent plane tangent to the vertex on the optical axis of the aspheric surface); r represents the distance of a point on the aspherical surface from the optical axis; k represents a conic coefficient (conic constant); r is_nRepresents a normalized curvature; u represents r/r_n；a_mRepresents an mth order aspherical surface coefficient; q_mRepresents the mth-order Qbfs polynomial. The advantage of using Qbfs polynomial to represent aspheric surface is that its surface type structure is more stable, is difficult to appear the abrupt change point, and the light is difficult to appear unusually.

In some embodiments, the lens assembly 1 determines lens parameters and aspheric coefficients of each lens of the lens group based on the gaps between the eight aspheric lenses and/or the thickness of each lens.

For example, the gaps and thicknesses between eight aspherical lenses satisfy the following conditions: 1.2< ALT/AAG < 3.0; wherein ALT is a sum of lens thicknesses of the first through eighth lenses 110 through 180; AAG is the sum of seven air gaps between the first lens 110 to the eighth lens 180. And/or the presence of a gas in the gas,

the thicknesses of the eight aspheric lenses satisfy the following conditional expressions: 2.0< Tmax/Tmin < 4.5; where Tmax is the maximum value of the thicknesses of the first lens 110 to the eighth lens 180, and Tmin is the minimum value of the thicknesses of the first lens 110 to the eighth lens 180. And/or the presence of a gas in the gas,

the clearance between the eight aspheric lenses satisfies the following conditional expression: 2.6< Gmax/Gmin < 25.0; where Gmax is the maximum value of seven air gaps between the first lens 110 to the eighth lens 180, and Gmin is the minimum value of seven air gaps between the first lens 110 to the eighth lens 180.

In some embodiments, the lens assembly 1 determines lens parameters and aspheric coefficients of each lens of the lens group based on the center thicknesses of the eight aspheric lenses.

For example, the center thicknesses of eight aspherical lenses satisfy the following conditional expressions:

0.9< (T1+ T6+ T7+ T8)/(T2+ T3+ T4+ T5) < 3; where T1 is the center thickness of the first lens 110, T2 is the center thickness of the second lens 120, T3 is the center thickness of the third lens 130, T4 is the center thickness of the fourth lens 140, T5 is the center thickness of the fifth lens 150, T6 is the center thickness of the sixth lens 160, T7 is the center thickness of the seventh lens 170, and T8 is the center thickness of the eighth lens 180. And/or the presence of a gas in the gas,

the center thicknesses of the eight aspheric lenses satisfy the following conditional expressions:

3< (T1+ T2+ T3+ T4+ T5)/T3< 8; where T1 is the center thickness of the first lens 110, T2 is the center thickness of the second lens 120, T3 is the center thickness of the third lens 130, T4 is the center thickness of the fourth lens 140, T5 is the center thickness of the fifth lens 150, T6 is the center thickness of the sixth lens 160, T7 is the center thickness of the seventh lens 170, and T8 is the center thickness of the eighth lens 180.

In some embodiments, the lens parameters and the spherical coefficients of the lenses of the lens group are determined based on the focal lengths of the eight aspheric lenses.

For example, the focal lengths of the eight aspherical lenses satisfy the following conditional expressions: 1.0< | f2/f1| < 4.5; where f1 is the focal length of the first lens 110 of the lens assembly 1, and f2 is the focal length of the second lens 120 of the lens assembly.

The focal lengths of the eight aspheric lenses satisfy the following conditional expressions: 0.23< | EFL/f2| + | EFL/f3| < 2.5. Wherein f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

In some embodiments, lens parameters and spherical coefficients of the lenses of the set are determined based on center distances between adjacent ones of the lenses.

For example, the center distances of the eight aspherical lenses satisfy the following conditional expressions:

1.5< (G23+ G34+ G56)/(G12+ G45+ G67+ G78) < 3.6; wherein G12 is the distance between the first lens element 110 and the second lens element 120 on the optical axis, G23 is the distance between the second lens element 120 and the third lens element 130 on the optical axis, G34 is the distance between the third lens element 130 and the fourth lens element 140 on the optical axis, G45 is the distance between the fourth lens element 140 and the fifth lens element 150 on the optical axis, G56 is the distance between the fifth lens element 150 and the sixth lens element 160 on the optical axis, G67 is the distance between the sixth lens element 160 and the seventh lens element 170 on the optical axis, and G78 is the distance between the seventh lens element 170 and the eighth lens element 180 on the optical axis.

The center distances of the eight aspheric lenses satisfy the following conditional expressions:

4< (G23+ G34+ G56+ OBFL)/(G12+ G45+ G67+ G78) < 14; wherein OBFL is a distance on the optical axis from the image side surface of the eighth lens 180 to the image plane.

In one embodiment, lens parameters and the aspheric coefficients are determined based on an entrance pupil diameter of the lens assembly

For example, the entrance pupil diameter satisfies the following conditional expression:

1.45< TL/EPD < 1.90; where EPD is the entrance pupil diameter of the lens assembly 1.

The entrance pupil diameter satisfies the following conditional expression:

16.0< HFOV EPD/EFL < 19.3; the HFOV is a half field angle of the lens assembly 1.

The entrance pupil diameter satisfies the following conditional expression: 2.8< TTL IMH/(EPD AP8) < 3.6; here, AP8 is the maximum effective radial dimension of the eighth lens 180.

0.95< ALT/BFL < 1.9; the BFL is a distance from a most salient point of the image side surface of the eighth lens 180 to the image surface along the optical axis direction.

0.58< CP72/CP82< 1.3; the CP72 is a distance from a critical point of the image side surface of the seventh lens element 170 to the optical axis, and the CP82 is a distance from a critical point of the image side surface of the eighth lens element 180 to the optical axis.

Based on the conditional expressions of the above embodiments, parameters of the lens assembly of the various embodiments of the present disclosure, including aspheric lens coefficients and aspheric coefficients, can be determined. In the following embodiments, 100 denotes the entrance pupil, i.e. the aperture, of the optical imaging system. A1-A30 are aspheric coefficients of 1 st to 30 th orders of each surface, K represents a conical surface coefficient in an aspheric curve equation, NR is a refractive index, and E is a scientific notation.

Example 1: fig. 4A is a schematic structural diagram of a lens assembly of the first embodiment shown in accordance with an exemplary embodiment of the present disclosure. Fig. 4B is a graph of spherical aberration, astigmatism, and distortion of fig. 4A shown in accordance with an exemplary embodiment of the present disclosure. Table 1-1 shows aspherical lens coefficients of the first embodiment according to an exemplary embodiment of the present disclosure. Tables 1-2 show aspheric coefficients of a first embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 4A and 4B, the aspherical lens coefficients (see table 1-1) and the aspherical lens coefficients (see table 1-2) of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 4B is a graph showing the spherical aberration, astigmatism and distortion of fig. 4A from left to right in sequence, and it can be seen from fig. 4B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 1-1

Tables 1 to 2

Example 2: fig. 5A is a schematic structural diagram of a lens assembly of a second embodiment shown in accordance with an exemplary embodiment of the present disclosure. Fig. 5B is a graph of spherical aberration, astigmatism, and distortion of fig. 5A shown in accordance with an exemplary embodiment of the present disclosure. Table 2-1 shows aspheric lens coefficients of the second embodiment according to an exemplary embodiment of the present disclosure. Table 2-2 shows aspheric coefficients of a second embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 5A and 5B, the aspherical lens coefficients (see table 2-1) and the aspherical lens coefficients (see table 2-2) of the lens assembly of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 5B is a graph showing the spherical aberration, astigmatism and distortion of fig. 5A from left to right in sequence, and it can be seen from fig. 5B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 2-1

Tables 2 to 2

Example 3: fig. 6A is a schematic structural diagram of a lens assembly according to a third embodiment shown in an exemplary embodiment of the present disclosure. Fig. 6B is a graph of spherical aberration, astigmatism, and distortion of fig. 6A shown in accordance with an exemplary embodiment of the present disclosure. Table 3-1 shows aspheric lens coefficients of a third embodiment according to an exemplary embodiment of the present disclosure. Table 3-2 shows aspheric coefficients of a third embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 6A and 6B, the aspherical lens coefficients (see table 3-1) and the aspherical lens coefficients (see table 3-2) of the lens assembly of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 6B is a graph showing the spherical aberration, astigmatism and distortion of fig. 6A from left to right in sequence, and it can be seen from fig. 6B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 3-1

TABLE 3-2

Example 4: fig. 7A is a schematic structural diagram of a lens assembly according to a fourth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 7B is a graph of spherical aberration, astigmatism, and distortion of fig. 7A shown in accordance with an exemplary embodiment of the present disclosure. Table 4-1 shows aspheric lens coefficients of a fourth embodiment according to an exemplary embodiment of the present disclosure. Table 4-2 is an aspheric coefficient of the fourth embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 7A and 7B, the aspherical lens coefficients (see table 4-1) and the aspherical lens coefficients (see table 4-2) of the lens assembly of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 7B is a graph showing the spherical aberration, astigmatism and distortion of fig. 7A from left to right in sequence, and it can be seen from fig. 7B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 4-1

TABLE 4-2

Example 5: fig. 8A is a schematic structural diagram of a lens assembly of a fifth embodiment shown in accordance with an exemplary embodiment of the present disclosure. Fig. 8B is a graph of spherical aberration, astigmatism, and distortion of fig. 8A shown in accordance with an exemplary embodiment of the present disclosure. Table 4-1 is an aspherical lens coefficient of the fifth embodiment shown according to an exemplary embodiment of the present disclosure. Table 4-2 is an aspheric coefficient of the fifth embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 8A and 8B, the aspherical lens coefficients (see table 5-1) and the aspherical lens coefficients (see table 5-2) of the lens assembly of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 8B is a graph of spherical aberration, astigmatism and distortion of fig. 8A from left to right in sequence, and it can be seen from fig. 8B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 5-1

TABLE 5-2

Example 6: fig. 9A is a schematic structural diagram of a lens assembly according to a sixth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 9B is a graph of spherical aberration, astigmatism, and distortion of fig. 9A shown in accordance with an exemplary embodiment of the present disclosure. Table 6-1 shows aspheric lens coefficients of a sixth embodiment according to an exemplary embodiment of the present disclosure. Table 6-2 is an aspheric coefficient of the sixth embodiment shown according to an exemplary embodiment of the present disclosure.

As shown in fig. 9A and 9B, by the conditional expressions of the above embodiments, the aspherical lens coefficient (see table 6-1) and the aspherical lens coefficient (see table 6-2) of the lens assembly of the present embodiment can be determined.

Fig. 9B is a graph showing the spherical aberration, astigmatism and distortion of fig. 9A from left to right in sequence, and it can be seen from fig. 9B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 6-1

TABLE 6-2

Example 7: fig. 10A is a schematic structural diagram of a lens assembly according to a seventh embodiment shown in an exemplary embodiment of the present disclosure. Fig. 10B is a graph of spherical aberration, astigmatism, and distortion of fig. 10A shown in accordance with an exemplary embodiment of the present disclosure. Table 7-1 shows aspherical lens coefficients of a seventh embodiment according to an exemplary embodiment of the present disclosure. Table 7-2 is an aspheric coefficient of the seventh embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 10A and 10B, the aspherical lens coefficients (see table 7-1) and the aspherical lens coefficients (see table 7-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 10B is a graph of spherical aberration, astigmatism and distortion of fig. 10A from left to right in sequence, and it can be seen from fig. 10B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 7-1

TABLE 7-2

Example 8: fig. 11A is a schematic structural diagram of a lens assembly according to an eighth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 11B is a graph of spherical aberration, astigmatism, and distortion of fig. 11A shown in accordance with an exemplary embodiment of the present disclosure. Table 8-1 shows aspheric lens coefficients of an eighth embodiment according to an exemplary embodiment of the present disclosure. Table 8-2 is an aspheric coefficient of the eighth embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 11A and 11B, the aspherical lens coefficients (see table 8-1) and the aspherical lens coefficients (see table 8-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 11B is a graph showing the spherical aberration, astigmatism and distortion of fig. 11A from left to right in sequence, and it can be seen from fig. 11B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 8-1

TABLE 8-2

Example 9: fig. 12A is a schematic structural diagram of a lens assembly of the ninth embodiment shown in accordance with an exemplary embodiment of the present disclosure. Fig. 12B is a graph of spherical aberration, astigmatism, and distortion of fig. 12A shown in accordance with an exemplary embodiment of the present disclosure. Table 9-1 shows aspherical lens coefficients of the ninth embodiment according to an exemplary embodiment of the present disclosure. Table 9-2 is an aspheric coefficient of the ninth embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 12A and 12B, the aspherical lens coefficient (see table 9-1) and the aspherical lens coefficient (see table 9-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 12B is a graph showing the spherical aberration, astigmatism and distortion of fig. 12A from left to right in sequence, and it can be seen from fig. 12B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 9-1

TABLE 9-2

Example 10: fig. 13A is a schematic structural diagram of a lens assembly according to a tenth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 13B is a graph of spherical aberration, astigmatism, and distortion of fig. 13A shown in accordance with an exemplary embodiment of the present disclosure. Table 10-1 shows aspheric lens coefficients of a tenth embodiment according to an exemplary embodiment of the present disclosure. Table 10-2 is an aspheric coefficient of the tenth embodiment shown according to an exemplary embodiment of the present disclosure.

Referring to fig. 13A and 13B, the aspherical lens coefficients (see table 10-1) and the aspherical lens coefficients (see table 10-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 13B is a graph showing the spherical aberration, astigmatism and distortion of fig. 13A from left to right, and it can be seen from fig. 13B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 10-1

TABLE 10-2

Example 11: fig. 14A is a schematic structural diagram of a lens assembly according to an eleventh embodiment shown in an exemplary embodiment of the present disclosure. Fig. 14B is a graph of spherical aberration, astigmatism, and distortion of fig. 14A shown in accordance with an exemplary embodiment of the present disclosure. Table 11-1 shows aspherical lens coefficients of the eleventh embodiment according to an exemplary embodiment of the present disclosure. Table 11-2 shows aspheric coefficients of the eleventh embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 14A and 14B, the aspherical lens coefficients (see table 11-1) and the aspherical lens coefficients (see table 11-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above-described embodiments.

Fig. 14B is a graph of spherical aberration, astigmatism and distortion of fig. 14A from left to right in sequence, and it can be seen from fig. 14B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 11-1

TABLE 11-2

Example 12: fig. 15A is a schematic structural diagram of a lens assembly according to a twelfth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 15B is a graph of spherical aberration, astigmatism, and distortion of fig. 15A shown in accordance with an exemplary embodiment of the present disclosure. Table 12-1 shows the aspherical lens coefficients of the twelfth embodiment according to an exemplary embodiment of the present disclosure. Table 12-2 shows aspheric coefficients of a twelfth embodiment according to an exemplary embodiment of the present disclosure.

As shown in fig. 15A and 15B, by the conditional expressions of the above-described embodiment, the aspherical lens coefficient (see table 12-1) and the aspherical lens coefficient (see table 12-2) of the lens module of the present embodiment can be determined.

Fig. 15B is a graph showing the spherical aberration, astigmatism and distortion of fig. 15A from left to right in sequence, and it can be seen from fig. 15B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 12-1

TABLE 12-2

Example 13: fig. 16A is a schematic structural diagram of a lens assembly according to a thirteenth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 16B is a graph of spherical aberration, astigmatism, and distortion of fig. 16A shown in accordance with an exemplary embodiment of the present disclosure. Table 13-1 shows aspherical lens coefficients of the thirteenth embodiment according to an exemplary embodiment of the present disclosure. Table 13-2 shows aspheric coefficients of a thirteenth embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 16A and 16B, the aspherical lens coefficient (see table 13-1) and the aspherical lens coefficient (see table 13-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 16B is a graph showing the spherical aberration, astigmatism and distortion of fig. 16A from left to right in sequence, and it can be seen from fig. 16B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 13-1

TABLE 13-2

Example 14: fig. 17A is a schematic structural diagram of a lens assembly according to a fourteenth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 17B is a graph of spherical aberration, astigmatism, and distortion of fig. 17A shown in accordance with an exemplary embodiment of the present disclosure. Table 14-1 shows aspherical lens coefficients according to a fourteenth embodiment according to an exemplary embodiment of the present disclosure. Table 14-2 is an aspheric coefficient of the fourteenth embodiment shown according to an exemplary embodiment of the present disclosure.

As shown in fig. 17A and 17B, the aspherical lens coefficient (see table 14-1) and the aspherical lens coefficient (see table 14-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 17B is a graph showing the spherical aberration, astigmatism and distortion of fig. 17A from left to right, and it can be seen from fig. 17B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 14-1

TABLE 14-2

Example 15: fig. 18A is a schematic structural diagram of a lens assembly according to a fifteenth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 18B is a graph of spherical aberration, astigmatism, and distortion of fig. 18A shown in accordance with an exemplary embodiment of the present disclosure. Table 15-1 shows aspherical lens coefficients of a fifteenth embodiment according to an exemplary embodiment of the present disclosure. Table 15-2 is an aspheric coefficient of the fifteenth embodiment shown according to an exemplary embodiment of the present disclosure.

As shown in fig. 18A and 18B, by the conditional expressions of the above-described embodiment, the aspherical lens coefficient (see table 15-1) and the aspherical lens coefficient (see table 15-2) of the lens module of the present embodiment can be determined.

Fig. 18B is a graph showing the spherical aberration, astigmatism and distortion of fig. 18A from left to right in sequence, and it can be seen from fig. 18B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 15-1

TABLE 15-2

Example 16: fig. 19A is a schematic structural diagram of a lens assembly according to a sixteenth embodiment shown in an exemplary embodiment of the present disclosure. Fig. 19B is a graph of spherical aberration, astigmatism, and distortion of fig. 19A shown in accordance with an exemplary embodiment of the present disclosure. Table 16-1 shows aspherical lens coefficients of a sixteenth embodiment according to an exemplary embodiment of the present disclosure. Table 16-2 shows aspheric coefficients of a sixteenth embodiment according to an exemplary embodiment of the present disclosure.

Referring to fig. 19A and 19B, the aspherical lens coefficient (see table 16-1) and the aspherical lens coefficient (see table 16-2) of the lens module of the present embodiment can be determined by the conditional expressions of the above embodiments.

Fig. 19B is a graph showing the spherical aberration, astigmatism and distortion of fig. 19A from left to right, and it can be seen from fig. 19B that the longitudinal spherical aberration, the astigmatism aberration, the field curvature aberration and the distortion of the present embodiment all conform to the usage specification.

TABLE 16-1

TABLE 16-2

In some embodiments, table 17 shows specific values of each parameter in embodiments 1 to 16. As shown in Table 17, the photosensitive element 300 of the disclosed embodiment has a photosensitive surface size of 14.29, i.e., 1/1.12 "inch, when the embodiments meet the following corresponding parameters.

TABLE 17

As shown in fig. 1 to 3, in some embodiments, the lens assembly 10 can move along the optical axis; when the lens assembly 1 is in an operating state, a distance between the lens group 10 and the image plane of the photosensitive element 200 is a first distance L1 (shown in fig. 2); when the lens assembly 1 is not in operation, the distance between the lens group 10 and the image plane of the photosensitive element 200 is a second distance L2 (shown in fig. 3), and the first distance L1 is greater than the second distance L2. Specifically, the lens assembly 1 includes a lens body movably disposed on the terminal body, and the lens group 10 is disposed in the lens body; when the lens assembly works, the lens body moves to the outside of the terminal body to drive the lens group to be far away from the photosensitive element; under the non-operating condition of the lens assembly, the lens body is moved to the outside of the terminal body to drive the lens assembly to be close to the photosensitive element.

A through hole for the lens body to pass through is formed in the rear shell of the terminal body, and the lens body can pass through the through hole and move to the inside and the outside of the terminal body in the thickness direction of the terminal body. When using, the lens body removes and passes the outside that the through-hole removed to the terminal body, drives the inside lens group 10 of lens body simultaneously and keeps away from photosensitive element 200 to carry out once to remove and focus as, after focusing the completion, come from the light of waiting to shoot the object and adjust the back via the lens refraction in lens group 10, throw photosensitive element again, 200 surfaces, photosensitive element 200 converts light information into digital information, handles through the inside treater of smart mobile phone again, presents on the screen. When the lens is not needed, the lens body is moved to the inside of the terminal body, and the lens group 10 inside the lens body is driven to be close to the photosensitive element 200, so as to shorten the length of the lens body.

According to the embodiment of the disclosure, the occupied space of the lens body on the terminal body in the thickness direction can be further shortened through the movable lens body, so that the thinning of the mobile terminal is facilitated, the number of the original lens groups 10 does not need to be changed, and the optical performance is ensured.

In an embodiment, the lens assembly 1 further includes a driving member for driving the lens group to move. Specifically, the driving member is disposed in the terminal body and drives the lens body to move.

The driving part can comprise a driving motor arranged on the middle frame of the terminal body, a gear in transmission connection with the driving motor and a rack meshed with the gear, wherein the rotation of the driving motor drives the gear to rotate, and the rotation of the driving motor is converted into linear motion through the rack transmission so as to drive the lens body to move, so that the lens group is far away from or close to the photosensitive element.

In another embodiment, the driving member includes a driving motor disposed in the terminal body and a screw in transmission connection with the driving motor, the screw is in threaded connection with the lens body, and the driving motor drives the screw to rotate, so as to drive the lens body to move into or out of the terminal body.

In another embodiment, the driving member includes a first electromagnetic component fixed in the terminal body and a second electromagnetic component fixed on the outer wall of the lens body, the first electromagnetic component and the second electromagnetic component are connected with the control circuit of the terminal, and the first electromagnetic component and the second electromagnetic component are controlled to change magnetism so as to attract or repel each other, so that the lens body moves.

In some embodiments, a color filter 190 is disposed between the photosensitive element 200 and the lens group 10, and the color filter 190 can move closer to or farther from the photosensitive element in the optical axis direction. Wherein, in the working state of the lens assembly 1, the distance between the color filter 190 and the imaging surface of the photosensitive element 200 is a third distance L3 (shown in fig. 3); when the lens assembly 1 is in the non-operating state, the distance between the color filter 190 and the image plane of the photosensitive element is the fourth distance L4 (shown in fig. 4), and the third distance L3 is greater than the fourth distance L4, so that when the lens body is close to or far away from the photosensitive element, a larger movement can be obtained, and the size of the lens body can be further reduced.

As shown in fig. 20, according to another aspect of the present disclosure, a mobile terminal 2 is provided, wherein the lens assembly 1 according to any embodiment of the first aspect is included.

The mobile terminal 2 comprises a terminal body 201, and the lens assembly 1 is arranged on the terminal body 201.

Through setting up this disclosed lens subassembly 1 for this disclosed mobile terminal 2 can more slim, and can acquire more clear effect of shooing, promotes user experience.

It is to be understood that the term "plurality" as used herein refers to two or more, and other terms are intended to be analogous. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. The singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms "first," "second," and the like are used to describe various information and that such information should not be limited by these terms. These terms are only used to distinguish one type of information from another and do not denote a particular order or importance. Indeed, the terms "first," "second," and the like are fully interchangeable. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present invention.

It will be further understood that the terms "central," "longitudinal," "lateral," "front," "rear," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the present embodiment and to simplify the description, but do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation.

It will be further understood that, unless otherwise specified, "connected" includes direct connections between the two without the presence of other elements, as well as indirect connections between the two with the presence of other elements.

It is further to be understood that while operations are depicted in the drawings in a particular order, this is not to be understood as requiring that such operations be performed in the particular order shown or in serial order, or that all illustrated operations be performed, to achieve desirable results. In certain environments, multitasking and parallel processing may be advantageous.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims

1. A lens assembly, comprising:

a lens group including a plurality of lenses;

the photosensitive element is positioned on the optical axis of the lens group and comprises an imaging surface;

wherein the lens parameters and aspheric coefficients of the plurality of lenses are determined based on at least one of the following three conditional expressions:

1.16<EFL/IMH<1.3；

1.3<TTL/TL<1.7；

1.2<EFL/TL<1.45；

wherein EFL is an effective focal length of the lens assembly; IMH is half the diagonal dimension of the imaging surface of the photosensitive element; TL is the distance from the object side surface to the image side surface of each lens in the lens group, which is closest to the most protruding position of the photosensitive element and is along the optical axis direction; TTL is a distance from an object-side surface of a lens closest to the object side in the lens group to the image plane of the photosensitive element on the optical axis.

2. The lens assembly of claim 1,

the lens group comprises eight lens elements, the lens elements are aspheric lens elements, and a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element are arranged in sequence from an object side to an image side.

3. The lens assembly of claim 2,

lens parameters of the plurality of lenses and the aspheric coefficients are determined based on a gap between the lenses and/or a thickness of each of the lenses.

4. The lens assembly of claim 3,

the gap and the thickness between the lenses satisfy the following conditions:

1.2<ALT/AAG<3.0；

wherein ALT is a sum of lens thicknesses of the first lens to the eighth lens; AAG is a sum of seven air gaps between the first lens to the eighth lens.

5. The lens assembly of claim 3,

the thickness of the lens satisfies the following conditional expression:

2.0<Tmax/Tmin<4.5；

6. The lens assembly of claim 3,

the gap between the lenses satisfies the following conditional expression:

2.6<Gmax/Gmin<25.0；

wherein Gmax is a maximum value of seven air gaps between the first lens to the eighth lens, and Gmin is a minimum value of seven air gaps between the first lens to the eighth lens.

7. The lens assembly of claim 3,

the lens parameters and aspheric coefficients are determined based on the center thickness of the lens.

8. The lens assembly of claim 7,

the center thickness of the lens satisfies the following conditional expression:

0.9<(T1+T6+T7+T8)/(T2+T3+T4+T5)<3；

wherein T1 is a center thickness of the first lens, T2 is a center thickness of the second lens, T3 is a center thickness of the third lens, T4 is a center thickness of the fourth lens, T5 is a center thickness of the fifth lens, T6 is a center thickness of the sixth lens, T7 is a center thickness of the seventh lens, and T8 is a center thickness of the eighth lens.

9. The lens assembly of claim 7,

3<(T1+T2+T3+T4+T5)/T3<8；

10. The lens assembly of claim 2,

the lens parameters and the aspheric coefficients are determined based on a focal length of the lens.

11. The lens assembly of claim 10,

the focal length of the lens satisfies the following conditional expression:

1.0<|f2/f1|<4.5；

wherein f1 is the focal length of the first lens, and f2 is the focal length of the second lens.

12. The lens assembly of claim 10,

the focal length of the lens satisfies the following conditional expression:

0.23<|EFL/f2|+|EFL/f3|<2.5；

wherein f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

13. The lens assembly of claim 2,

determining the lens parameters and the aspheric coefficients based on a center distance between adjacent lenses.

14. The lens assembly of claim 13,

the center distance of the lens satisfies the following conditional expression:

1.5<(G23+G34+G56)/(G12+G45+G67+G78)<3.6；

15. The lens assembly of claim 13,

the center distance of the lens satisfies the following conditional expression:

4<(G23+G34+G56+OBFL)/(G12+G45+G67+G78)<14；

wherein G12 is the distance between the first lens element and the second lens element on the optical axis, G23 is the distance between the second lens element and the third lens element on the optical axis, G34 is the distance between the third lens element and the fourth lens element on the optical axis, G45 is the distance between the fourth lens element and the fifth lens element on the optical axis, G56 is the distance between the fifth lens element and the sixth lens element on the optical axis, G67 is the distance between the sixth lens element and the seventh lens element on the optical axis, G78 is the distance between the seventh lens element and the eighth lens element on the optical axis, and OBFL is the distance between the image side surface of the eighth lens element and the image plane on the optical axis.

16. The lens assembly of claim 2,

the lens parameters and the aspheric coefficients are determined based on an entrance pupil diameter of a lens assembly.

17. The lens assembly of claim 16,

the entrance pupil diameter satisfies the following conditional expression:

1.45<TL/EPD<1.90；

wherein EPD is the entrance pupil diameter of the lens assembly.

18. The lens assembly of claim 16,

the entrance pupil diameter satisfies the following conditional expression:

16.0<HFOV*EPD/EFL<19.3；

wherein EPD is the entrance pupil diameter of the lens assembly; the HFOV is a half field angle of the lens assembly.

19. The lens assembly of claim 16,

the entrance pupil diameter satisfies the following conditional expression:

2.8<TTL*IMH/(EPD*AP8)<3.6；

wherein EPD is the entrance pupil diameter of the lens assembly; AP8 is the maximum effective radial dimension of the eighth lens.

20. The lens assembly of claim 2,

determining the lens parameters and the aspheric coefficients based on the following conditional expressions:

0.95<ALT/BFL<1.9；

and BFL is the distance from the most salient point of the image side surface of the eighth lens to the imaging surface along the optical axis direction.

21. The lens assembly of claim 2,

0.58<CP72/CP82<1.3；

wherein CP72 is a distance from a critical point of the image side surface of the seventh lens element to the optical axis, and CP82 is a distance from a critical point of the image side surface of the eighth lens element to the optical axis.

22. The lens assembly of any one of claims 1 to 21,

the lens group can move along the direction of the optical axis;

when the lens assembly works, the distance between the lens group and the imaging surface of the photosensitive element is a first distance; when the lens assembly is in a non-working state, the distance between the lens group and the imaging surface of the photosensitive element is a second distance, and the first distance is greater than the second distance.

23. The lens assembly of claim 22, wherein the lens assembly comprises:

the driving piece is used for driving the lens group to move.

24. The lens assembly of claim 22,

a color filter is arranged between the photosensitive element and the lens group, and the color filter can move close to or far away from the photosensitive element along the optical axis direction;

when the lens assembly is in a working state, the distance between the color filter and the imaging surface of the photosensitive element is a third distance; when the lens assembly is in a non-working state, the distance between the color filter and the imaging surface of the photosensitive element is a fourth distance, and the third distance is greater than the fourth distance.

25. A mobile terminal, comprising:

the lens assembly of any one of claims 1 to 24.