AU2020101479A4

AU2020101479A4 - A Multi-zone Contact Lens with the Function of Controlling the Progression of Myopia and Its Application Method

Info

Publication number: AU2020101479A4
Application number: AU2020101479A
Authority: AU
Inventors: Yayan BIAN; Yongji LIU
Original assignee: Nankai University
Current assignee: Nankai University
Priority date: 2020-07-24
Filing date: 2020-07-24
Publication date: 2020-08-27
Anticipated expiration: 2028-07-24

Abstract

The invention proposed a multi-zone contact lens with the function of controlling the progression of myopia and an application method thereof, including a lens body, the said lens body comprises a myopia correction zone, a myopia treatment zone and a contact matching zone for wearing and fixing the contact lens, wherein the said myopia correction zone is a zone that can fully correct myopic refractive error, the said myopia treatment zone is a zone that can produce myopic defocus along the peripheral retina; by setting a rotationally symmetric multi-zone aspherical/spherical surface as the anterior surface of the lens body, the present invention can avoid the use of aspherical surfaces to reduce the manufacture difficulty, and the surface parameters of each zone of the anterior surface of the lens body can be flexibly adjusted, i.e. by adjusting the size of each zone and the add refractive power, the central vision correction ability and the peripheral myopic defocus can be effectively adjusted, so as to achieve personalized designs according to different personal needs. Drawings of Descriptions 2 * 3 1 1 2 Fig.1 1.0 , i , 0.9 0.8 0.7 0.6 0. 5 0.4 0.3 0.2 0.1 -+ 0 (degree)-- 5 (degree)-+- 10 (degree) ~ 0.0 1 1 1 1 1 1 0 10 20 30 40 50 60 70 80 90 100 Spatial Frequency / cycles per mm Fig.2 1/3

Description

Drawings of Descriptions

2 * 3

1 1 2 Fig.1

1.0 , i ,

0.9

0.8

0.7

0.6

0. 5

0.4 0.3

0.2

0.1 -+ 0 (degree)-- 5 (degree)-+- 10 (degree) ~ 0.0 1 1 1 1 1 1 0 10 20 30 40 50 60 70 80 90 100 Spatial Frequency / cycles per mm

Fig.2

1/3

Descriptions

A Multi-zone Contact Lens with the Function of Controlling the Progression of Myopia and Its Application Method

Technical Field

[0001]The present invention relates to the technical field of vision correction, and in particular to a multi-zone contact lens with the function of controlling the progression of myopia and its application method thereof.

Background Technology

[0002]Myopia is currently the most common refractive error among children and adolescents in most parts of the world. In addition, the age of myopia onset in many countries is getting younger. An earlier myopia onset may accelerate the progression of myopia, which in turn increases the severity of myopia and the risks of related eye diseases such as cataracts, glaucoma and retinal degeneration. The design of contact lenses that can control the progression of myopia is expected to slow the progression of myopia in children and adolescents, and has potential application value.

[0003]The main methods for controlling the progression of myopia include atropine, orthokeratology, bifocal or progressive multifocal spectacles, and bifocal or multifocal contact lenses. However, there are certain deficiencies and side effects, such as the possibility of causing photophobia, decreased accommodation, discomfort in wearing, infection risk and dizziness.

[0004] The commercial CooperVision Misight is a bifocal contact lens, which is proven to be an effective way to control myopia progression. However, it is reported that the peripheral myopic defocus provided by this contact lens is only 2D. Clinical studies show that greater peripheral myopic defocus can more effectively control the progression of myopia, but the peripheral myopic defocus of the existing contact lens design basically does not exceed 4D, which is to be further increased. In addition, there is no clear relationship between the design parameters of contact lenses and the peripheral defocus for human eyes. Therefore, the present invention proposed a multi-zone contact lens with the function of controlling the progression of myopia and an application method, which provides greater peripheral myopia defocus to solve the deficiencies in the prior art.

Summary of the Invention

[0005] The present invention set the anterior surface of the contact lens to be a rotationally symmetric multi-zone aspherical/spherical surface. In this way, the surface parameters therefrom can be flexibly adjusted, i.e. by adjusting the area size of each zone of the lens body and the add refractive power, the central vision correction ability and the provided peripheral myopia defocus can be effectively adjusted, so that personalized customization based on different personal needs can be achieved.

Descriptions

[0006] The present invention proposes a multi-zone contact lens with the function of controlling the progression of myopia, including a lens body, characterized in that: the said lens body includes a myopia correction zone, a myopia treatment zone and a contact matching zone for wearing and fixing the contact lens, wherein the said myopia correction zone is a zone that can fully correct myopic refractive error, the said myopia treatment zone is a zone that can produce myopic defocus along the peripheral retina; the anterior surface of the said lens body is a rotationally symmetric multi-zone aspherical/spherical surface, and is divided into five concentric radial zones by5 radial coordinates of Al, A 2, A 3 , A4 and A5 , the five concentric radial zones are zone 1, zone 2, zone 3, zone 4, and zone 5 in sequence from the inside to the outside, wherein the said zone 1 belongs to the myopia correction zone (1), the said zones 2, 3 and 4 form an outer zone, in the said outer zone, the zone 2 and the zone 4 belong to the myopia treatment zone (2), the zone 3 belongs to the myopia correction zone (1) and the said zone 5 belongs to the contact matching zone for wearing and fixing the contact lens (3);

[0007]The said zones 1, 2, 3, 4 and 5 have their independent aperture sizes (A), curvatures (c), conic constant (k), and aspheric coefficients (a) of each order;

[0008]The said zone extends from the center vertex of the contact lens to the radial coordinate A 1, the zone 2 extends from the radial coordinate Ai to the radial coordinate A 2, and the zone 3 extends from the radial coordinate A 2 to the radial coordinate A 3, and so on, until the last zone An, where 0 <A<A 2<... <An;

[0009]In the said zones 1, 2, 3, 4 and 5, there is a sag deviation value Zo between each zone and the previous zone, which keeps the sag of the surface continuous at the boundary between the current zone and the previous one. The sag of zone j can be expressed by formulaO:

C .2 NI

[0010] Z (r) = 1 + - 1+ k c© + a +Z

[0011]In formula j, ej presents the curvature at the vertex of the asperical surface in the zone j, r represents the radial distance from any point on the asperical surface to the optical axis, pj represents the normalized radial coordinate of the zone j, and pj = r /Aj, kjrepresents the conic constant of the zone j, Na represents the number of the aspherical coefficients, and aji represents the aspherical coefficients of each order of the zone j;

[0012]Zo is the sag deviation value between each zone and the previous zone, which can be expressed by formula @.

[0013] Zo=Zj 1-(Aj-i)-Zj(Aj)

[0014]A further improvement is that the lens body is a flexible or rigid optical lens made of any

Descriptions

one of hydro-gel, silicon hydro-gel or rigid gas permeable/pervious material.

[0015]Another further improvement is that the radial coordinate Ai corresponding to the myopia correction zone has a range of 1.5 mm to 2.2 mm, the diameter range is 3.2mm to 4.8mm; the radial coordinate A 2 corresponding to the myopia treatment zone used for treating myopia in the outer zone has a range of 2mm to 4mm, the diameter range is 3 mm to 8.2 mm; the radial coordinate corresponding to the contact matching zone (3) is with a range of 6mm to7. 2mm, the diameter range is 20mm to 14.2mm.

[0016]Another further improvement is that the basic diopter of the lens body ranges from -0.5D to -8.22D.

[0017]Another further improvement is that the central thickness of the effective optics of the said lens body ranges from 0.04 mm to 0.2 mm, and the range of the peripheral myopic defocus provided by the myopia treatment zone (2) is -3D to -18D.

[0018Another further improvement is that the said multi-zone contact lens can effectively change the imaging performance and the peripheral defocusing conditions by changing the size of each zone of the lens body and the add therapeutic power; by increasing the area size of the myopia correction zone (1), the central vision correction ability can be improved, providing better imaging quality; by increasing the add diopter of the myopia treatment zone (2), the peripheral myopia defocus can be effectively increased to better control the progression of myopia; the application method specifically includes the steps of:

[0019]Step 1: Use the Zemax software to build an Atchison human eye model, then select the myopic human eye model of SR = -3Din the Atchison human eye model, and select the material of the lens;

[0020]Step 2: Select the radius of curvature of each zone of the anterior surface of the lens body, the radius of curvature of the posterior surface of the lens body, and the conic constant of the surface;

[0021]Step 3: Under the photopic vision with the pupil of 3mmand the object distance of infinity, calculate the MTF of the eye model value at the spatial frequency of 50c / mm within the field of view of 0 °- 10 °

[0022]Step 4: Under the photopic vision with the pupil diameter of 3mm, calculate the peripheral defocus value of the human eye model in the field of view of 0 °- 35 °.

[0023] Another further improvement is that after the myopic human eye model with SR = -3D in step 1 is selected, then rc = 7.704; vl = 17.177; rx= -12.628, Qx = 0.192; ry = -12.732, Qy =0.199.

Descriptions

[0024] Another further improvement is that the radius of curvature of the posterior surface of the lens body in step 2 is 7.704 mm, and the conic constant of the surface is -0.15.

[0025] The beneficial effects of the present invention are in that: the contact lens of the present invention can fully correct myopic refractive error under the photopic vision, which meets the actual visual needs of human eyes, and at the same time it presents a greater peripheral myopic defocus under both the photopic vision and the scotopic vision, and the range of peripheral myopic defocus provided shows the potential of effective control of the progression of myopia. By setting a rotationally symmetric multi-zone aspherical/spherical surface as the anterior surface of the lens body, the invention can reduce the difficulty of manufacturing. Furthermore, the surface parameters of each zone of the anterior surface of the lens body can be flexibly adjusted, i.e. by adjusting the area size of each zone of the lens body and the add refractive power, the central vision correction ability and the peripheral myopia defocus provided can be effectively adjusted, so that personalized customization based on different personal needs can be achieved.

Brief Description of the Drawings

[0026] Fig. 1 is a schematic anterior view of the structure of the present invention.

[0027] Fig. 2 is a schematic diagram of an MTF curve under the photopic vision according to Embodiment 1 of the present invention for field of view of 0 0 - 10 °.

[0028] Fig. 3 is a schematic diagram of the variation curve of peripheral defocus vs field of view under the photopic vision and the scotopic vision according to Embodiment 1 of the present invention.

[0029] Fig.4 is a schematic diagram of an MTF curve under the photopic vision according to Embodiment 2 of the present invention for field of view of 0 ° - 10 °.

[0030] Fig. 5 is a schematic diagram of the curve of peripheral defocus vs field of view under the photopic vision and the scotopic vision according to Embodiment 2 of the present invention.

[0031] Where: 1- myopia correction zone, 2- myopia treatment zone, 3- contact matching zone.

Detailed Description of the Preferred Embodiments

[0032]The present invention will be further described below in conjunction with the preferred embodiment for a broad understanding of the invention. The embodiment is to be used for explaining the present invention only, and not to constitute a limitation to the protection scope of the present invention.

[0033] Embodiment 1

Descriptions

[0034]The Atchison human eye model was established in the Zemax software, whose structural parameters are shown in Table 1. The myopic human eye model with SR = -3D was selected, then rc = 7.704; v = 17.177; rx = -12.628, Qx = 0.192; ry = -12.732, Qy = 0.199. Based on this eye model, the optimization design and performance analysis of the contact lens were carried out. The lens body used the BalaficonA of silicon hydro-gel material, with a refractive index of 1.422.

[0035]T able 1 Structural parameters of the Atchison eye model

Zemaxsur Refractive

[0036] face index(Medium) Radius ThicknessAspheric

(mm) /mm ity type (555nm)

Standa Air 1 rd

Anterio Standa rcornea rd 1.376 re 0.55 -0.15

[0037]

Posteri Standa 1.3374 6.4 3.15 -0.275 orcornea rd

Standa Infini Pupil 1.3374 0 0 rd ty

Anterior Gradie GradA 11.48 1.44 -5 lens nt

Grade -Infin Equator GradP 2.16 0 nt ity

Posterior Standa 1.336 -5.9 vI -2 lens rd

Biconi Retina - rx,ry - Qx,Qy c

[0038] rc=7.77+0.022SR.

[0039] GradA= 1.371+0.0652778Z-0.0226659Z2-0.0020399(X2+Y2).

[0040] GradP= 1.418-0.0100737Z2-0.0020399(X2+Y2).

[0041] vl=16.28-0.299SR.

Descriptions

[0042] rx=-12.91-0.094SR,Qx=0.27+0.026SR.

[0043] ry=-12.72+0.004SR,Qy=0.25+0.017SR.

[0044] Aperturetype:floatbystopsize.

[0045] In accordance with Fig. 1, 2 and 3, this embodiment proposes a multi-zone contact lens with the function of controlling the progression of myopia, including a lens body, the said lens body includes a myopia correction zone 1, a myopia treatment zone 2 and a contact matching zone for wearing and fixing the contact lens 3, wherein the said myopia correction zone 1 is a zone that can fully correct myopic refractive error, the said myopia treatment zone 2 is a zone that can produce myopic defocus along the peripheral retina; the anterior surface of the said lens body is a rotationally symmetric multi-zone aspherical/spherical surface, and is divided into five concentric radial zones by 5 radial coordinates of Ai, A 2, A 3 , A 4 and A5 , the said five concentric radial zones are zone 1, zone 2, zone 3, zone 4, and zone 5 in sequence from the inside to the outside, wherein the said zone 1 belongs to the myopia correction zone (1), the said zones 2, 3 and 4 form an outer zone, in the said outer zone, the zone 2 and the zone 4 belong to the myopia treatment zone (2), the zone 3 belongs to the myopia correction zone (1) and the said zone 5 belongs to the contact matching zone for wearing and fixing the contact lens (3);

[0046JFhe said zones 1, 2, 3, 4 and 5 have their independent aperture sizes (A), curvatures (c), conic constant (k), and aspheric coefficients (a) of each order;

[0047]The said zone extends from the center vertex of the contact lens to the radial coordinate A 1, the zone 2 extends from the radial coordinate Ai to the radial coordinate A 2, and the zone 3 extends from the radial coordinate A 2 to the radial coordinate A 3, and so on, until the last zone An, where 0 <A<A 2<... <An;

[0048]In the said zones 1, 2, 3, 4 and 5, there is a sag deviation value Zo between each zone and the previous zone, which keeps the sag of the surface continuous at the boundary between the current zone and the previous zone. The sag of zone j can be expressed by formulaO: c .r2 *

[0049] (r)= 1 + + ap +

1 - + k(1 c rk r2

[0050]In formula ), cj presents the curvature at the vertex of the asperical surface in the zone j, r represents the radial distance from any point on the asperical surface to the optical axis, pj represents the normalized radial coordinate of the zone j, and pj = r / Aj, kjrepresents the conic constant of the zone j, Na represents the number of the aspherical coefficients, and ajirepresents the aspherical coefficients of each order of the zone j;

[0051]Zo is the sag deviation value between each zone and the previous zone, which can be

Descriptions

expressed by formula ().

[0052] Zo =Zj-1 (Aj-1) -Zj (Aj)()

[0053] In accordance with the axially symmetrical characteristics of the concentric radial zones, the posterior surface is the same as the anterior corneal surface by default. The anterior surface adopts a multi-zone spherical surface, which is divided into 5 concentric radial zones (n= 5) by A1

, A 2 , A 3 , A 4 and A5 , where the radial coordinates A1 = 1.75mm, A 2 = 2.25mm, A 3 = 3mm, A 4 = 4.3mm and A5 = 7.1mm, and the radii of curvature of the five zones on the anterior surface of the contact lens are optimized to form alternating myopia correction zones and treatment zones. Finally, the radius of curvature of each zone is obtained.

[0054]The radius of curvature of each zone of the anterior surface is shown in Table 2:

[0055] Table 2 The radii of curvature of the 5 zones on the anterior surface of the lens body

[0056]

Zones Radiusl Radius2 Radius3 Radius4 Radius5 Radius of Curvature (mm) 8. 172 6.955 8.221 7.348 8.6

[0057]The basic parameters of the posterior surface of the contact lens: the radius of curvature is 7.704mm, and the conic constant is -0.15.

[0058]The basic parameters of the multi-zone contact lens: the basic refractive power of the lens body is -3D, the diameter is 14.2 mm, and the central thickness is 0.0659 mm.

[0059]The imaging performance and the peripheral defocus of the human eye model fitted with the multi-zone contact lens are as follows:

[0060]As shown in Fig. 2, the MTF of the human eye model at the spatial frequency of 50 /

mm for the field of view of 0 0 - 10 0 is greater than 0.56 under a photopic vision with a pupil diameter of 3mm, indicating that this contact lens has excellent imaging quality in the field of view of 0 0 - 10 °,which exhibits excellent ability to correct myopia under the photopic vision.

[0061]As shown in Fig. 3, the defocus of the eye fitted with the contact lensis close to OD for field of view of u nder the photopic vision with a pupil diameter of 3 mm. Whereas the peripheral defocus reaches as high as -5.45D for field of view of 20 °. The peripheral defocus value reaches -6D for field of view of 350 under the scotopic vision with a pupil diameter of 6 mm. That means this contact lens can completely correct myopic refractive error under the photopic vision, and shows a greater peripheral myopic defocus under both the photopic vision and the scotopic vision, exhibiting a potential to control the progression of myopia.

[0062] In accordance with the analysis results of Fig. 2 and 3, it can be concluded that this multi-zone contact lens is able to fully correct myopic refractive error of the eye model and

Descriptions

provides excellent imaging quality for field of view between 0 ° and 10 °. In addition, the multi-zone contact lens can produce greater peripheral defocus under both the photopic vision and the scotopic vision, which exhibits the ability to control the progress of myopia of the human eye.

[0063] Embodiment 2

[0064]Referring to the design method in Embodiment 1, only the size of zones on the surface of the lens body is changed, and the add diopter of the 2 treatment zone is increased,

[0065] As shown in Fig. 1, 4 and 5, this embodiment proposes a multi-zone contact lens with the function of controlling the progression of myopia, including a lens body, the said lens body includes a myopia correction zone 1, a myopia treatment zone 2 and a contact matching zone for wearing and fixing the contact lens 3, wherein the said myopia correction zone 1 is a zone that can fully correct myopic refractive error, the said myopia treatment zone 2 is a zone that can produce myopic defocus along the peripheral retina; the anterior surface of the said lens body is a rotationally symmetric multi-zone aspherical/spherical surface, and is divided into five concentric radial zones by 5 radial coordinates of A1 , A 2 , A 3 , A 4 and A5 , the five concentric radial zones are zone 1, zone 2, zone 3, zone 4, and zone 5 in sequence from the inside to the outside, wherein the said zone 1 belongs to the myopia correction zone (1), the said zones 2, 3 and 4 form an outer zone, in the said outer zone, the zone 2 and the zone 4 belong to the myopia treatment zone (2), the zone 3 belongs to the myopia correction zone (1) and the said zone 5 belongs to the contact matching zone for wearing and fixing the contact lens (3);

[0066]The said zones 1, 2, 3, 4 and 5 have their independent aperture sizes (A), radii of curvature (c), conic constant (k), and aspheric coefficients (a) of each order;

[0067]The said zone 1 extends from the center vertex of the contact lens to the radial coordinate A 1, the zone 2 extends from the radial coordinate A1 to the radial coordinate A 2, and the zone 3 extends from the radial coordinate A 2 to the radial coordinate A 3 , and so on, until the last zone An, where 0 <A<A 2<... <An;

[0068]In the said zones 1, 2, 3, 4 and 5, there is a sag deviation value Zo between each zone and the previous zone, which keeps the sag of the surface continuous at the boundary between the current zone and the previous zone. The sag of zone j can be expressed by formulaO:

[0069] 2r)= 1++1 a+)p +Z (D 1 + F -07 (1+ _cr2 i=

[0070]In formula , cj presents the curvature at the vertex of the asperical surface in the zone j, r represents the radial distance from any point on the asperical surface to the optical axis, pj represents the normalized radial coordinate of the zone j, and pj = r / Aj, kjrepresents the conic

Descriptions

constant of the zone j, Na represents the number of the aspherical coefficients, and ajirepresents the aspherical coefficients of each order of the zone j;

[0071]Zo is the sag deviation value between each zone and the previous zone, which can be expressed by formula ().

[0072] Zo =Zj-1 (Aj-1) -Zj (Aj)()

[0073]The five radial coordinates are A 1 = 2mm, A 2 = 3mm, A 3 = 3.58mm, A 4 = 4.5mm and A 5 = 7.1mm, and the radii of curvature of the five zones on the anterior surface of the contact lens are optimized to form alternating myopia correction zones and treatment zones. Finally, the radius of curvature of each zone is obtained.

[0074]The radius of curvature of each zone of the anterior surface is shown in Table 3:

[0075]Table 3 The radii of curvature of the 5 zones on the anterior surface of the lens body

[0076]

Zones Radius1 Radius2 Radius3 Radius4 Radius5

Radius of Curvature 8.163 6.955 8.221 7.268 8.6 (mm)

[0077]The basic parameters of the multi-zone contact lens: the basic refractive power of the lens body is -3D, the diameter is 14.2 mm, and the central thickness is 0.08 mm

[0078]The imaging performance and the peripheral defocus of the human eye model fitted with the multi-zone contact lens are as follows:

[0079]As shown in Fig. 4, the MTF value at a spatial frequency of 50 c / mm is above 0.6 for field of view between 0 ° and 100 under the photopic vision with a pupil diameter of 3 mm, indicating an excellent imaging quality for the field of view between 0 0 and 10 0, i.e. excellent ability to correct myopic refractive error.

[0080]As shown in Fig. 5, the defocus value is close to OD for field of view of 0 under the photopic vision with a pupil diameter or 3 mm. However, the peripheral defocus is -10.41D for peripheral field of 20 0 and -6.32D for 35 °. These have shown that in addition to fully correct myopic refractive error, the multi-zone contact lens is able to provide quite large peripheral myopic defocus under the photopic vision, exhibiting the ability to control the progression of myopia

[0081]It can be concluded from the comparison between Embodiment 1 and Embodiment 2 that

Descriptions

changing the area size of a zone of the lens body and the add therapeutic refractive power can effectively change the imaging performance and the peripheral defocus of the eye fitted with the contact lens; it can be found from the comparison between Fig. 2 and Fig. 4 that increasing the area size of the myopia correction zone 1 can improve the central vision correction ability and provide better imaging quality; it can be found from the comparison between Fig. 3 and Fig. that increasing the add diopter of the myopia treatment zone 2 can effectively increase the peripheral myopic defocus, so as to better control the progression of myopia.

[0082]The contact lens of the present invention can completely correct myopic refractive error under the photopic vision, which meets the actual visual needs of human eyes. Furthermore, the contact lens shows large peripheral myopia defocus above -5 D under both the photopic vision and the scotopic vision, the range of peripheral defocusing provided herein shows the potential of effective control of the progression of myopia, and the surface parameters of each zone on the anterior surface of the lens body can be flexibly adjusted, i.e.by adjusting the area size of each zone of the lens body and the add refractive power, the central vision correction ability and the peripheral myopia defocus provided can be effectively adjusted, so that personalized design based on different personal needs can be achieved.

[0083]The above description is given to illustrate the basic principles, main features and advantages of the present invention. Those skilled in the art should appreciate that the present invention is in no way to be limited by the foregoing embodiments thereof. The preferred embodiments and the detailed description are merely for clearness of understanding. Without departing from the spirit and scope of the present invention, various changes and improvements can be made to the invention, and all such changes and improvements should fall within the scope as is protected by the claims. The protection scope of the present invention is limited by the appended claims and their equivalents.

Claims

1. A multi-zone contact lens with the function of controlling the progression of myopia, including a lens body, characterized in that: the said lens body includes a myopia correction zone (1), a myopia treatment zone (2) and a contact matching zone for wearing and fixing the contact lens (3), wherein the said myopia correction zone (1) is a zone that can fully correct myopic refractive error, the said myopia treatment zone (2) is a zone that can produce myopic defocus along the peripheral retina; the anterior surface of the said lens body is a rotationally symmetric multi-zone aspherical/spherical surface, and is divided into five concentric radial zones by 5 radial coordinates of Ai, A 2, A 3, A 4 and A5 , the said five concentric radial zones are zone 1, zone 2, zone 3, zone 4, and zone 5 in sequence from the inside to the outside, wherein the said zone 1 belongs to the myopia correction zone (1), the said zones 2, 3 and 4 form an outer zone, in the said outer zone, the zone 2 and the zone 4 belong to the myopia treatment zone (2), the zone 3 belongs to the myopia correction zone (1) and the said zone 5 belongs to the contact matching zone for wearing and fixing the contact lens (3);

The said zones 1, 2, 3, 4 and 5 have their independent aperture sizes (A), curvatures (c), conic constant (k), and aspheric coefficients (a) of each order;

The said zone 1 extends from the center vertex of the contact lens to the radial coordinate A 1, the zone 2 extends from the radial coordinate A1 to the radial coordinate A 2, and the zone 3 extends from the radial coordinate A 2 to the radial coordinate A 3, and so on, until the last zone An, where 0 <Ai<A 2<... <An;

In the said zones 1, 2, 3, 4 and 5, there is a sag deviation value Zo between each zone and the previous zone, which keeps the sag of the surface continuous at the boundary between the current zone and the previous one. The sag of zone j can be expressed by formulaO:

c 2

I + CIT 1+ 1 -(1+kg) c2r2

In formula j, cj presents the curvature at the vertex of the aspherical surface in the zone j, r represents the radial distance from any point on the aspherical surface to the optical axis, pjrepresents the normalized radial coordinate of the zone j, and pj = r / Aj, kjrepresents the conic constant of the zone j, Na represents the number of the aspherical coefficients, and aji represents the aspherical coefficients of each order of the zone j;

Zo is the sag deviation value between each zone and the previous one, which can be expressed by formula@. Zo= Zj-1 (Aj-1) -Zj (Aj) @

2. A multi-zone contact lens with the function of controlling the progression of myopia according to claim 1 wherein the lens body is a flexible or rigid optical lens made of any one of hydro-gel, silicon hydro-gel or rigid gas permeable/pervious material.

Claims 3. A multi-zone contact lens with the function of controlling the progression of myopia according to claim 1 wherein the radial coordinate Ai corresponding to the myopia correction zone (1) has a semi-diameter ranging from 1.5 mm to 2.2 mm; the radial coordinate A 2 corresponding to the myopia treatment zone (2) used for myopia treatment has a semi-diameter of 2mm to 4mm; the radial coordinate corresponding to the contact matching zone (3) is with a range of 6mm to 7. 2mm.

4. A multi-zone contact lens with the function of controlling the progression of myopia according to claim 1 wherein the basic diopter of the lens body ranges from -0.5D to -8.22D.

5. A multi-zone contact lens with the function of controlling the progression of myopia according to claim 1 wherein the central thickness of the effective optics of the said lens body ranges from 0.04 mm to 0.2 mm, and the range of the peripheral myopic defocus provided by the myopia treatment zone (2) is -3D to -18D.

6.An application method of the multi-zone contact lens with the function of controlling the progression of myopia wherein the said multi-zone contact lens can effectively change the imaging performance and the peripheral defocusing conditions by changing the size of each zone of the lens body and the add power in the myopia treatment zone; by increasing the size of the myopia correction zone (1), the central vision correction ability can be improved, providing better imaging quality; by increasing the add diopter of the myopia treatment zone (2), the peripheral myopia defocus can be effectively increased so as to better control the progression of myopia; the application method specifically includes the steps of:

Step 1: Use the Zemax software to build an Atchison human eye model, then select the myopic human eye model with SR = -3Din the Atchison human eye model, and select the material of the contact lens;

Step 2: Select the radius of curvature of each zone of the anterior surface of the lens body, the radius of curvature of the posterior surface of the lens body, and the conic constant of the surface;

Step 3: Under the photopic vision with the pupil of 3mmand the object distance of infinity, calculate the MTF value at the spatial frequency of 5c / mm for field of view of 0 °- 10 0;

Step 4: Under the photopic vision with the pupil diameter of 3mm, calculate the peripheral defocus of the human eye model for field of view of 0 °- 35 °.

7. An application method of the multi-zone contact lens with the function of controlling the progression of myopia according to claim 6 wherein after the myopic human visual system with SR = -3D in step 1 is selected, then rc = 7.704; vl = 17.177; rx= -12.628, Qx = 0.192; ry = -12.732, Qy = 0.199.

8. An application method of the multi-zone contact lens with the function of controlling the progression of myopia according to claim 6 wherein the radius of curvature of the posterior surface

Claims of the lens body in step 2 is 7.704 mm, and the conic constant of the surface is -0.15.