Myopia prevention and control optical path system of Fresnel lens

Abstract

The utility model belongs to the technical field of myopia prevention and control devices, and discloses a Fresnel lens myopia prevention and control light path system which comprises a main lens cone assembly, a secondary lens cone assembly, an LED light source assembly and a collimating lens set. The main lens cone assembly is connected with the secondary lens cone assembly, an inner cavity of the main lens cone assembly and an inner cavity of the secondary lens cone assembly form a light transmission channel, and the LED light source assembly is arranged at the rear end of the main lens cone assembly; the collimating lens group is arranged in the inner cavity of the main lens barrel assembly and comprises at least one first aspheric positive meniscus lens, at least one second aspheric positive meniscus lens and at least one Fresnel lens; the Fresnel lens is fixedly arranged at the front end of the main lens cone assembly, and the centers of the LED light source assembly, the first aspherical positive meniscus lens, the second aspherical positive meniscus lens and the Fresnel lens are coaxially aligned. According to the utility model, the optical path efficiency, the lightweight degree and the economical efficiency are obviously improved, and the flexibility and the anti-interference capability of the structure are enhanced.

Description

Technical Field

[0001] This utility model belongs to the technical field of myopia prevention and control devices, and more specifically, it relates to a Fresnel lens optical path system for myopia prevention and control. Background Technology

[0002] In recent years, the demand for myopia control has been increasing, and phototherapy technology has gradually become a research hotspot due to its non-invasive nature. Traditional myopia control devices mostly use laser light sources combined with conventional lens systems. Although they have high directionality, they have significant drawbacks: laser light sources are prone to power surges, which may cause irreversible damage; while conventional lenses (such as biconvex lenses) are large and heavy, making the devices bulky and difficult to portability. In addition, existing optical systems generally suffer from insufficient light spot uniformity, and uneven light energy distribution can easily lead to localized over-brightness or under-brightness, affecting the treatment effect.

[0003] To improve beam uniformity, some solutions employ multiple aspherical lenses for repeated small-angle collimation. For example, an aspherical positive meniscus lens is used to adjust the angles of the central and peripheral optical paths, combined with a beam-diffusing lens. However, such systems rely on precision-machined aspherical lenses, resulting in high manufacturing costs. Furthermore, the stacking of multiple lenses leads to complex structures and difficult assembly. Simultaneously, stray light reflected from the inner wall of the lens barrel is difficult to suppress, further reducing optical path efficiency and the purity of the output beam.

[0004] On the other hand, the thick design of traditional lenses limits the development of lightweight and modular optical systems. Although the use of lightweight materials can partially alleviate the weight problem, the size of the optical components themselves and the processing technology still restrict cost control and mass production.

[0005] Therefore, this utility model provides a Fresnel lens optical path system for myopia prevention and control. Utility Model Content

[0006] In view of the above-mentioned problems of existing technology, the purpose of this utility model is to provide a Fresnel lens optical path system for myopia prevention and control, which significantly improves optical path efficiency, lightweighting and economy, while enhancing structural flexibility and anti-interference ability, and provides a better solution for the practical application and popularization of myopia prevention and control equipment.

[0007] The objective of this utility model can be achieved through the following technical solutions:

[0008] A Fresnel lens optical path system for myopia control includes a main lens barrel assembly, a secondary lens barrel assembly, an LED light source assembly, and a collimating lens group;

[0009] The main lens assembly is connected to the secondary lens assembly, and the inner cavity of the main lens assembly and the inner cavity of the secondary lens assembly form a light transmission channel. The LED light source assembly is installed at the rear end of the main lens assembly.

[0010] The collimating lens group is disposed in the inner cavity of the main lens barrel assembly, and the collimating lens group includes at least one first aspherical positive meniscus lens, at least one second aspherical positive meniscus lens, and at least one Fresnel lens.

[0011] The Fresnel lens is fixedly mounted at the front end of the main lens barrel assembly, and the centers of the LED light source assembly, the first aspherical positive meniscus lens, the second aspherical positive meniscus lens, and the Fresnel lens are coaxially aligned.

[0012] As a further preferred technical solution of this utility model, a light-diffusing lens is installed at the front end of the secondary lens assembly. The light-diffusing lens is coaxially aligned with the center of each lens of the collimating lens group, and the light-diffusing lens is arranged opposite to the Fresnel lens. The collimated beam emitted by the LED light source assembly is refracted by the Fresnel lens and then forms a uniform light spot through the light-diffusing lens.

[0013] As a further preferred technical solution of this utility model, the Fresnel lens is a double-sided Fresnel structure, the exit surface of the Fresnel lens is a plane, and the incident surface of the Fresnel lens is an annular sawtooth microstructure used to enhance the collimation effect of the beam.

[0014] As a further preferred technical solution of this utility model, the main lens tube assembly includes a first main lens tube body, a second main lens tube body and a third main lens tube body, wherein the front end of the first main lens tube body is connected to the rear end of the second main lens tube body, and the front end of the second main lens tube body is connected to the rear end of the third main lens tube body.

[0015] The first main lens barrel is basin-shaped. The bottom of the rear end of the first main lens barrel is provided with several screw holes. The first main lens barrel is connected to the LED light source assembly through several screw holes. The outer periphery of the front end of the first main lens barrel is provided with a first internally screwed annular edge. An internal thread is provided on the inner diameter of the first internally screwed annular edge.

[0016] The second main lens barrel is tubular in shape. A first externally threaded annular edge is provided on the outer periphery of the rear end of the second main lens barrel. An external thread is provided on the outer diameter of the first externally threaded annular edge. The external thread of the first externally threaded annular edge is threaded with the internal thread of the first internally threaded annular edge. A first mounting groove is provided on the inner diameter of the first externally threaded annular edge. The first aspherical positive meniscus lens is installed in the first mounting groove. A second internally threaded annular edge is provided on the outer periphery of the front end of the second main lens barrel. An internal thread is provided on the inner diameter of the second internally threaded annular edge.

[0017] The third main lens barrel is tubular in shape. A second externally threaded annular edge is provided on the outer periphery of the rear end of the third main lens barrel. An external thread is provided on the outer diameter of the second externally threaded annular edge, and the external thread of the second externally threaded annular edge is threaded into the internal thread of the second internally threaded annular edge. A second mounting groove is provided on the inner diameter of the second externally threaded annular edge, and the second aspherical positive meniscus lens is installed in the second mounting groove. A third mounting groove is provided in the middle of the inner cavity of the third main lens barrel, and the Fresnel lens is installed in the third mounting groove. A third internally threaded annular edge is provided on the front end of the third main lens barrel, and an internal thread is provided on the inner diameter of the third internally threaded annular edge.

[0018] As a further preferred technical solution of this utility model, the secondary lens tube assembly includes a secondary lens tube body and an end cap, wherein the secondary lens tube body is connected to the end cap.

[0019] The secondary lens barrel is an annular body. The front and rear ends of the outer wall of the secondary lens barrel are provided with external threads. The secondary lens barrel assembly is connected to the main lens barrel assembly through the external thread at the rear end of the outer wall of the secondary lens barrel.

[0020] The end cap is an annular body, and an internal thread is provided on the inner wall of the end cap. The internal thread of the inner wall of the end cap is screwed to the external thread at the front end of the outer wall of the secondary lens barrel.

[0021] As a further preferred technical solution of this utility model, the inner walls of the first main lens barrel body, the second main lens barrel body and the third main lens barrel body of the main lens barrel assembly are all provided with a black matte light-absorbing layer, and the diameter of the inner cavity of the main lens barrel assembly formed by connecting the first main lens barrel body, the second main lens barrel body and the third main lens barrel body gradually increases along the light transmission direction.

[0022] The inner walls of the secondary lens barrel body and the end cap of the secondary lens barrel assembly are both provided with a black matte light-absorbing layer.

[0023] As a further preferred technical solution of this utility model, the LED light source assembly includes a circuit aluminum substrate, on which a plurality of light-emitting diodes are disposed, and on which a connection circuit for connecting the plurality of light-emitting diodes by wires is also disposed.

[0024] The circuit aluminum substrate has mounting through holes, and the LED light source assembly is fixed to the main lens barrel assembly through the mounting through holes of the circuit aluminum substrate.

[0025] As a further preferred technical solution of this utility model, the light-diffusing lens is a frosted diffuser used to convert collimated beams into uniformly divergent light, and its surface roughness Ra is 0.8-1.5μm.

[0026] As a further preferred technical solution of this utility model, the ratio of the focal length of the Fresnel lens to the focal length of the first aspherical positive meniscus lens and the second aspherical positive meniscus lens is 1:1.2-1.5.

[0027] As a further preferred technical solution of this utility model, the first main lens barrel body, the second main lens barrel body and the third main lens barrel body of the main lens barrel assembly, as well as the secondary lens barrel body and the end cap of the secondary lens barrel assembly, are all made of lightweight composite materials, and the thickness of the Fresnel lens is 1 / 3 to 1 / 2 of the thickness of a traditional biconvex lens.

[0028] As described above, the Fresnel lens optical path system for myopia control provided by this utility model has the following beneficial effects:

[0029] 1. This utility model utilizes a Fresnel lens-based optical path system for myopia control. Compared with existing technologies, this system, by replacing the continuous curved surface of traditional lenses with the annular sawtooth microstructure of the Fresnel lens, significantly reduces material usage and thickness while maintaining the same optical performance. This improvement makes the overall optical path system lighter, especially suitable for portable myopia control devices, enhancing user convenience. Furthermore, the Fresnel lens has a planar exit surface and an annular sawtooth structure on the incident surface, which effectively enhances the collimation effect of the beam and reduces scattering losses in the optical path. In addition, combined with a homogenizing lens, the collimated beam is further diffused into a uniform light spot, optimizing the uniformity of the light field distribution, thus better meeting the stable illumination conditions required for myopia control.

[0030] 2. This utility model utilizes a Fresnel lens-based optical path system for myopia control. Compared with existing technologies, Fresnel lenses can be mass-produced through injection molding or compression molding processes. Compared with the precision machining of traditional aspherical lenses, its manufacturing process is simpler and less costly. At the same time, the thin design of Fresnel lenses simplifies the internal installation structure of the lens barrel, reduces assembly difficulty, and improves production efficiency. Furthermore, the focal length of Fresnel lenses forms a specific ratio with that of traditional aspherical lenses, which can flexibly adapt to different optical path requirements. In addition, the diameter of the inner cavity of the main lens barrel components gradually increases along the light transmission direction. Combined with the thin characteristics of Fresnel lenses, the optical path system is easier to modularize, facilitating later maintenance or functional expansion.

[0031] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a Fresnel lens optical path system for myopia control according to this utility model application;

[0034] Figure 2 A cross-sectional view of a Fresnel lens optical path system for myopia control according to this utility model application;

[0035] Figure 3 This is a schematic diagram of the Fresnel lens structure of a myopia control optical path system according to this utility model application;

[0036] Figure 4 This is a schematic diagram of the LED light source assembly of a Fresnel lens optical path system for myopia control, which is the subject of this utility model application.

[0037] Summary of figure labels and their descriptions:

[0038] 100. Main lens barrel assembly; 110. First main lens barrel body; 120. Second main lens barrel body; 130. Third main lens barrel body; 200. Secondary lens barrel assembly; 210. Beam leveling lens; 220. Secondary lens barrel body; 230. End cap; 300. LED light source assembly; 310. Circuit aluminum substrate; 320. Light emitting diode; 400. Collimating lens group; 410. First aspherical positive meniscus lens; 420. Second aspherical positive meniscus lens; 430. Fresnel lens; 431. Plane; 432. Annular serrated microstructure. Detailed Implementation

[0039] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0040] It should be noted that the structures, proportions, and sizes depicted in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention. Specific structures can be described with reference to the accompanying drawings of the patent application.

[0041] This utility model provides a structural schematic diagram of a Fresnel lens 430 optical path system for myopia control. Please refer to [the diagram]. Figures 1 to 4 As shown, it includes a main lens barrel assembly 100, a secondary lens barrel assembly 200, an LED light source assembly 300, and a collimating lens group 400;

[0042] The main lens barrel assembly 100 is connected to the secondary lens barrel assembly 200. The inner cavity of the main lens barrel assembly 100 and the inner cavity of the secondary lens barrel assembly 200 form a light transmission channel. The LED light source assembly 300 is installed at the rear end of the main lens barrel assembly 100.

[0043] The collimating lens group 400 is disposed in the inner cavity of the main lens tube assembly 100, and the collimating lens group 400 includes at least one first aspherical positive meniscus lens 410, at least one second aspherical positive meniscus lens 420 and at least one Fresnel lens 430.

[0044] The Fresnel lens 430 is fixedly disposed at the front end of the main lens barrel assembly 100, and the centers of the LED light source assembly 300, the first aspherical positive meniscus lens 410, the second aspherical positive meniscus lens 420, and the Fresnel lens 430 are coaxially aligned.

[0045] The secondary lens assembly 200 is provided with a light-diffusing lens 210 at its front end. The light-diffusing lens 210 is coaxially aligned with the centers of each lens in the collimating lens group 400, and the light-diffusing lens 210 is positioned opposite to the Fresnel lens 430. The collimated beam emitted by the LED light source assembly 300 is refracted by the Fresnel lens 430 and then passes through the light-diffusing lens 210 to form a uniform light spot.

[0046] Combination Figure 3 As shown, the Fresnel lens 430 is a double-sided Fresnel structure. The exit surface of the Fresnel lens 430 is a plane 431, and the incident surface of the Fresnel lens 430 is an annular sawtooth microstructure 432 used to enhance the collimation effect of the beam. By designing the annular sawtooth microstructure 432 on the incident surface of the Fresnel lens 430, this invention can significantly reduce the amount of material used while ensuring optical performance, thereby achieving a lighter weight and smaller size, making products using the Fresnel lens 430 more convenient to carry and install.

[0047] The main lens barrel assembly 100 includes a first main lens barrel body 110, a second main lens barrel body 120, and a third main lens barrel body 130. The front end of the first main lens barrel body 110 is connected to the rear end of the second main lens barrel body 120, and the front end of the second main lens barrel body 120 is connected to the rear end of the third main lens barrel body 130.

[0048] The first main lens barrel 110 is basin-shaped. The bottom of the first main lens barrel 110 is provided with several screw holes. The first main lens barrel 110 is connected to the LED light source assembly 300 through several screw holes. The outer periphery of the front end of the first main lens barrel 110 is provided with a first internally screwed annular edge. The inner diameter of the first internally screwed annular edge is provided with an internal thread.

[0049] The second main lens barrel 120 is tubular in shape. A first externally threaded annular edge is provided on the outer periphery of the rear end of the second main lens barrel 120. An external thread is provided on the outer diameter of the first externally threaded annular edge. The external thread of the first externally threaded annular edge is threaded with the internal thread of the first internally threaded annular edge. A first mounting groove is provided on the inner diameter of the first externally threaded annular edge. The first aspherical positive meniscus lens 410 is installed in the first mounting groove. A second internally threaded annular edge is provided on the outer periphery of the front end of the second main lens barrel 120. An internal thread is provided on the inner diameter of the second internally threaded annular edge.

[0050] The third main lens barrel 130 is tubular in shape. A second externally threaded annular edge is provided on the outer periphery of the rear end of the third main lens barrel 130. An external thread is provided on the outer diameter of the second externally threaded annular edge. The external thread of the second externally threaded annular edge is threaded with the internal thread of the second internally threaded annular edge. A second mounting groove is provided on the inner diameter of the second externally threaded annular edge. The second aspherical positive meniscus lens 420 is installed in the second mounting groove. A third mounting groove is provided in the middle of the inner cavity of the third main lens barrel 130. The Fresnel lens 430 is installed in the third mounting groove. A third internally threaded annular edge is provided on the front end of the third main lens barrel 130. An internal thread is provided on the inner diameter of the third internally threaded annular edge.

[0051] The secondary lens barrel assembly 200 includes a secondary lens barrel body 220 and an end cap 230, wherein the secondary lens barrel body 220 is connected to the end cap 230.

[0052] The secondary lens barrel 220 is an annular body. The front and rear ends of the outer wall of the secondary lens barrel 220 are provided with external threads. The secondary lens barrel assembly 200 is connected to the main lens barrel assembly 100 through the external thread at the rear end of the outer wall of the secondary lens barrel 220.

[0053] The end cap 230 is an annular body, and an internal thread is provided on the inner wall of the end cap 230. The internal thread of the inner wall of the end cap 230 is screwed to the external thread at the front end of the outer wall of the secondary lens barrel 220.

[0054] The inner walls of the first main lens barrel 110, the second main lens barrel 120, and the third main lens barrel 130 of the main lens barrel assembly 100 are all provided with a black matte light-absorbing layer, and the diameter of the inner cavity of the main lens barrel assembly 100 formed by connecting the first main lens barrel 110, the second main lens barrel 120, and the third main lens barrel 130 gradually increases along the light transmission direction.

[0055] The inner walls of the secondary lens barrel 220 and the end cap 230 of the secondary lens barrel assembly 200 are both provided with a black matte light-absorbing layer.

[0056] It should be noted that the inner walls of the first main lens barrel 110, the second main lens barrel 120, and the third main lens barrel 130 of the main lens barrel assembly 100, as well as the inner walls of the secondary lens barrel 220 and the end cap 230 of the secondary lens barrel assembly 200, are all provided with a black matte light-absorbing layer. Combined with the high-efficiency collimation capability of the Fresnel lens 430, this can further suppress stray light reflected from the inner wall of the lens barrel, reduce optical path interference, and ensure the purity and stability of the output light spot.

[0057] Combination Figure 4 As shown, the LED light source assembly 300 includes a circuit aluminum substrate 310, on which a plurality of light-emitting diodes 320 are disposed, and on which a connection circuit for connecting the plurality of light-emitting diodes 320 by wires is also disposed.

[0058] The circuit aluminum substrate 310 has mounting through holes, and the LED light source assembly 300 is fixed to the main lens barrel assembly 100 through the mounting through holes of the circuit aluminum substrate 310.

[0059] The light-diffusing lens 210 is a frosted diffuser used to convert collimated beams into uniformly divergent light, and its surface roughness Ra is 0.8-1.5μm.

[0060] The ratio of the focal length of the Fresnel lens 430 to the focal lengths of the first aspherical positive meniscus lens 410 and the second aspherical positive meniscus lens 420 is 1:1.2-1.5.

[0061] The first main lens barrel 110, the second main lens barrel 120, and the third main lens barrel 130 of the main lens barrel assembly 100, as well as the secondary lens barrel 220 and the end cap 230 of the secondary lens barrel assembly 200, are all made of lightweight composite materials, and the thickness of the Fresnel lens 430 is 1 / 3 to 1 / 2 of the thickness of a traditional biconvex lens.

[0062] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A Fresnel lens optical path system for myopia control, characterized in that, It includes the main lens barrel assembly, the secondary lens barrel assembly, the LED light source assembly, and the collimating lens group; The main lens assembly is connected to the secondary lens assembly, and the inner cavity of the main lens assembly and the inner cavity of the secondary lens assembly form a light transmission channel. The LED light source assembly is installed at the rear end of the main lens assembly. The collimating lens group is disposed in the inner cavity of the main lens barrel assembly, and the collimating lens group includes at least one first aspherical positive meniscus lens, at least one second aspherical positive meniscus lens, and at least one Fresnel lens. The Fresnel lens is fixedly mounted at the front end of the main lens barrel assembly, and the centers of the LED light source assembly, the first aspherical positive meniscus lens, the second aspherical positive meniscus lens, and the Fresnel lens are coaxially aligned.

2. The myopia control optical path system using a Fresnel lens according to claim 1, characterized in that, The secondary lens assembly is equipped with a light-diffusing lens at its front end. The light-diffusing lens is coaxially aligned with the centers of each lens in the collimating lens group, and the light-diffusing lens is positioned opposite to the Fresnel lens. The collimated beam emitted by the LED light source assembly is refracted by the Fresnel lens and then passes through the light-diffusing lens to form a uniform light spot.

3. The myopia control optical path system using a Fresnel lens according to claim 1, characterized in that, The Fresnel lens is a double-sided Fresnel structure. The exit surface of the Fresnel lens is a plane, and the incident surface of the Fresnel lens is a ring-shaped sawtooth microstructure used to enhance the collimation effect of the beam.

4. The myopia control optical path system using a Fresnel lens according to claim 1, characterized in that, The main lens tube assembly includes a first main lens tube body, a second main lens tube body, and a third main lens tube body. The front end of the first main lens tube body is connected to the rear end of the second main lens tube body, and the front end of the second main lens tube body is connected to the rear end of the third main lens tube body. The first main lens barrel is basin-shaped. The bottom of the rear end of the first main lens barrel is provided with several screw holes. The first main lens barrel is connected to the LED light source assembly through several screw holes. The outer periphery of the front end of the first main lens barrel is provided with a first internally screwed annular edge. An internal thread is provided on the inner diameter of the first internally screwed annular edge. The second main lens barrel is tubular in shape. A first externally threaded annular edge is provided on the outer periphery of the rear end of the second main lens barrel. An external thread is provided on the outer diameter of the first externally threaded annular edge. The external thread of the first externally threaded annular edge is threaded with the internal thread of the first internally threaded annular edge. A first mounting groove is provided on the inner diameter of the first externally threaded annular edge. The first aspherical positive meniscus lens is installed in the first mounting groove. A second internally threaded annular edge is provided on the outer periphery of the front end of the second main lens barrel. An internal thread is provided on the inner diameter of the second internally threaded annular edge. The third main lens barrel is tubular in shape. A second externally threaded annular edge is provided on the outer periphery of the rear end of the third main lens barrel. An external thread is provided on the outer diameter of the second externally threaded annular edge, and the external thread of the second externally threaded annular edge is threaded into the internal thread of the second internally threaded annular edge. A second mounting groove is provided on the inner diameter of the second externally threaded annular edge, and the second aspherical positive meniscus lens is installed in the second mounting groove. A third mounting groove is provided in the middle of the inner cavity of the third main lens barrel, and the Fresnel lens is installed in the third mounting groove. A third internally threaded annular edge is provided on the front end of the third main lens barrel, and an internal thread is provided on the inner diameter of the third internally threaded annular edge.

5. The myopia control optical path system using a Fresnel lens according to claim 1, characterized in that, The secondary lens tube assembly includes a secondary lens tube body and an end cap, wherein the secondary lens tube body is connected to the end cap. The secondary lens barrel is an annular body. The front and rear ends of the outer wall of the secondary lens barrel are provided with external threads. The secondary lens barrel assembly is connected to the main lens barrel assembly through the external thread at the rear end of the outer wall of the secondary lens barrel. The end cap is an annular body, and an internal thread is provided on the inner wall of the end cap. The internal thread of the inner wall of the end cap is screwed to the external thread at the front end of the outer wall of the secondary lens barrel.

6. A Fresnel lens optical path system for myopia control according to claim 4 or 5, characterized in that, The inner walls of the first main lens barrel body, the second main lens barrel body, and the third main lens barrel body of the main lens barrel assembly are all provided with a black matte light-absorbing layer, and the diameter of the inner cavity of the main lens barrel assembly formed by connecting the first main lens barrel body, the second main lens barrel body, and the third main lens barrel body gradually increases along the light transmission direction. The inner walls of the secondary lens barrel body and the end cap of the secondary lens barrel assembly are both provided with a black matte light-absorbing layer.

7. The myopia control optical path system using a Fresnel lens according to claim 1, characterized in that, The LED light source assembly includes a circuit aluminum substrate, on which a plurality of light-emitting diodes are disposed, and on which a connection circuit for connecting the plurality of light-emitting diodes by wires is also disposed. The circuit aluminum substrate has mounting through holes, and the LED light source assembly is fixed to the main lens barrel assembly through the mounting through holes of the circuit aluminum substrate.

8. The myopia control optical path system using a Fresnel lens according to claim 2, characterized in that, The light-diffusing lens is a frosted diffuser used to convert collimated beams into uniformly divergent light, with a surface roughness Ra of 0.8-1.5 μm.

9. A Fresnel lens optical path system for myopia control according to claim 1, characterized in that, The ratio of the focal length of the Fresnel lens to the focal lengths of the first aspherical positive meniscus lens and the second aspherical positive meniscus lens is 1:1.2-1.

5.

10. A Fresnel lens optical path system for myopia control according to claim 6, characterized in that, The first main lens barrel body, the second main lens barrel body, and the third main lens barrel body of the main lens barrel assembly, as well as the secondary lens barrel body and end cap of the secondary lens barrel assembly, are all made of lightweight composite materials, and the thickness of the Fresnel lens is 1 / 3 to 1 / 2 of the thickness of a traditional biconvex lens.

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