Myopia prevention and control glasses of photon-like sieve model and design method of myopia prevention and control glasses

Abstract

The invention provides a pair of myopia prevention and control glasses of a photon-like sieve model, which comprises a lens main body, and an optical correction area, a defocus area and an edge arc area are concentrically arranged on the lens main body; the defocus area is arranged between the optical correction area and the edge arc area, the defocus area is provided with a photon sieve, the photon sieve is composed of a series of small holes distributed in concentric rings, and the arrangement of the small holes meets a window function; and the light transmission of the defocus area is lower than that of the optical correction area. The photon sieve meeting the window function is introduced into the defocus area of the myopia prevention and control lens, pupil dependence of a single refraction type optical design is overcome, the imaging quality of a traditional Fresnel diffraction lens is improved, the high-order diffraction and the side lobe effect are restrained, clear and stable myopia defocus is provided, meanwhile, a low-contrast environment is formed in the retina, and therefore the myopia prevention and control lens can be used for preventing and controlling myopia. And a refraction and diffraction mixed system is formed by utilizing the opposite dispersivity of the photon sieve and a traditional refraction material, so that the chromatic aberration problem of the photon sieve serving as a diffraction optical element is solved.

Description

Technical Field

[0001] This application relates to the field of lens technology for correcting refractive errors, and in particular to a myopia control lens based on a photon sieve model and its design method. Background Technology

[0002] The growth and refractive development of the eyeball require visual guidance. The main visual signals affecting eye growth and development are contrast signals and defocus signals. Both of these signals are processed inside the eyeball. Therefore, the visual environment composed of these signals creates a visually sensitive area of ​​10°–20° concavity in the macula of our eye to adapt to exposure to various light intensities and other visual environments. The function of the retina is to encode all light intensities while remaining sensitive to subtle changes in intensity and changes in the level of light. Because the electrical response range of neurons in the retina is relatively narrow, in order to transmit a large amount of information in a timely manner, the signals emitted by the retina vary according to relative intensity (i.e., contrast), rather than absolute light intensity values. That is, myopia prevention not only relies on the formation of myopic defocus around the fovea of ​​the retina, but also on low retinal contrast. However, there is a lack of product designs on the market that simultaneously achieve both low retinal contrast and myopic defocus signals.

[0003] In recent years, defocus lenses have been increasingly widely used in myopia control in my country. Several studies have evaluated their effectiveness in myopia control. Compared to orthokeratology lenses, defocus lenses offer higher safety and fewer usage restrictions, thus they are widely used in myopia control. Most defocus soft lenses on the market are refractive designs, highly dependent on the pupil. Among numerous diffractive elements, Fresnel diffractive lenses are a representative structure. For example, Chinese invention patent CN111766719A discloses a myopia control optical lens and its manufacturing method, which improves imaging effects and controls myopia progression through a multi-fractal Fresnel zone plate lens. With continuous technological development, the resolving power requirements of optical systems are increasing. However, due to its physical nature, the resolving power of a Fresnel lens is determined by the width of its outermost ring, and limited by current microfabrication capabilities, its resolving power is constrained by the width of its outermost ring. Therefore, the highest resolution of defocus lenses with Fresnel waves will be limited by the current manufacturing level. Thus, it is necessary to develop myopia control lenses that can simultaneously achieve low retinal contrast and myopia defocus signal to overcome the limitations of existing defocus lens imaging. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned technical problems and provide a myopia control lens that can simultaneously achieve low retinal contrast and myopia defocus signal using a photon sieve-like model.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a myopia control lens, comprising a lens body, on which an optical correction zone, a defocus zone, and an edge arc zone are concentrically arranged; the defocus zone is located between the optical correction zone and the edge arc zone, and the defocus zone is provided with a photon sieve, which consists of a series of small holes distributed on concentric rings, the arrangement of the small holes satisfying a window function; the light transmittance of the defocus zone is lower than that of the optical correction zone.

[0006] Furthermore, the window function is selected from one or a combination of a triangular window function, a rectangular window function, a Hamming window function, a Gaussian window function, and a Fibonacci sequence distribution function. A window function is a mathematical function used in signal processing to reduce spectral leakage.

[0007] Furthermore, the photon sieve arrangement is either monofocal or bifocal; a monofocal arrangement means the photon sieve arrangement satisfies a single window function; a bifocal arrangement means the photon sieve arrangement simultaneously satisfies two window functions. The bifocal arrangement is formed by overlapping two photon sieves with different focal lengths to create a photon sieve with partially overlapping sieve apertures.

[0008] Furthermore, the single-focal design of the photon sieve can stably provide myopia defocus, and in conjunction with the emmetropic signal provided by the central optical correction zone, a dual-focal design can also be adopted to simultaneously provide emmetropic signal and myopia defocus signal.

[0009] Furthermore, the defocus area and / or the edge arc area are opaque components. The opaque nature of the defocus area and / or the edge arc area reduces projection and facilitates the creation of a low-contrast environment on the retina; the edge arc area is far from the central optical correction zone and does not affect the entrance pupil light.

[0010] Preferably, the defocus area and / or edge arc area can be made of opaque material, which can be achieved by using opaque coating, photolithography, deposition, molding, printing, or machine processing, etc., while the optical correction area is made of transparent material.

[0011] Furthermore, the diameter of the photonic sieve is 1-5 mm. Preferably, the photonic sieve is a micro-nano transparent aperture.

[0012] Furthermore, the diameter of the optical correction area is 1~7 mm; the diameter of the edge arc area is 1~5 mm.

[0013] Furthermore, the minimum size of the pores in the photonic sieve is larger than the wavelength of visible light; preferably, the wavelength is 546 nm.

[0014] Furthermore, the photon-screen myopia control lens is a soft contact lens, a rigid contact lens, a spectacle lens, or an artificial lens.

[0015] Furthermore, the base material of the photon sieve myopia control lens is silicone hydrogel, hydrogel, fluorosilicone acrylate, or acrylate.

[0016] Furthermore, the photon sieve satisfies: Distance from the center of the aperture to the center of the photon sieve plane Satisfying equation (Ⅰ) (I) In formula (Ⅰ) For the incident light wavelength, For focal length, This refers to the number of individual holes in a single ring on a concentric ring. Small hole diameter Satisfying equation (II) (II) In formula (II) This is the proportionality coefficient, with the most commonly used value being 1.5; Total number of rings on concentric rings N Satisfying equation (Ⅲ) (III) In formula (Ⅲ) This indicates the aperture of the photon sieve.

[0017] The present invention also provides a design method for the above-mentioned myopia control glasses, comprising the following steps: S1. Determine the photon sieve parameters: based on the focal length The distances from the center of the aperture to the center of the photon sieve plane are obtained sequentially. Small hole diameter The total number of rings on concentric rings N ; and modulate the aperture distribution of the photon sieve using a window function; S2. Prepare a photon sieve that meets the above parameters in the defocus region.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) In view of the fact that the existing technology cannot achieve both peripheral defocus and low contrast at the same time, the present invention develops a soft lens for myopia control. It introduces a photon sieve model, abandons the pupil dependence of refractive optical design, improves the imaging quality of traditional Fresnel diffraction lenses, suppresses higher-order diffraction and sidelobe effects, and provides clear and stable myopia defocus while forming a low-contrast environment on the retina, thereby further enhancing the myopia control capability of the soft lens.

[0019] (2) By applying photon sieves to myopia control lenses, this invention utilizes the opposite dispersive properties of photon sieves and traditional refractive materials to form a refractive-diffractive hybrid system, which can achieve better correction of the chromatic aberration of photon sieves and overcome the problem of obvious chromatic aberration when photon sieves are used as diffractive optical elements in broadband light. Attached Figure Description

[0020] Figure 1 A schematic diagram of the lens body of the myopia control lens of the present invention; In the diagram, 1 represents the optical correction area, 2 represents the defocus area, and 3 represents the edge arc area.

[0021] Figure 2 A schematic diagram of the photonic sieve structure of the myopia control lens of this invention, where λ is the incident light wavelength. d n The diameter of the small hole.

[0022] Figure 3 To construct the photon sieve diffraction model, a coordinate system XYZ is established with the center of the photon sieve.

[0023] Figure 4 Diagram of a photon sieve structure modulated by a Fibonacci window function.

[0024] Figure 5 The amplitude distribution of the photon sieve spectrum modulated by the Fibonacci window function (logarithmic).

[0025] Figure 6 Radial average spectrum of a photon sieve modulated by a Fibonacci window function.

[0026] Figure 7 The distribution of photon sieve apertures modulated by triangular window function, rectangular window function, Hamming window function and Fibonacci window function.

[0027] Figure 8 Normalized light intensity distribution of a unit light intensity incident on a photon sieve, where a represents the myopia control lens prepared in Example 2; b represents the Fresnel lens. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to specific embodiments. The embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0029] Example 1 This embodiment provides a myopia control lens based on a photon sieve model, such as... Figure 1 As shown, the lens body includes an optical correction area 1, a defocus area 2 and an edge arc area 3 concentrically arranged on the lens body; the defocus area 2 is located between the optical correction area 1 and the edge arc area 3, and the defocus area 2 is provided with a photon sieve, which consists of a series of small holes distributed on concentric rings, and the arrangement of the small holes satisfies a window function.

[0030] As an option, the window function can be selected from one or a combination of triangular window functions, rectangular window functions, Hamming window functions, Hanning window functions, Gaussian window functions, Fibonacci sequence distribution functions, etc. Window functions are mathematical functions used in signal processing to reduce spectral leakage; for a specific window function, the distribution of apertures on the photon sieve can be determined.

[0031] The formula for a partial window function is as follows: Triangular window function:

[0032] Where n represents the index position of the current point, and N represents the total length of the window (that is, the total number of sampling points).

[0033] Rectangular window function:

[0034] Where n represents the index position of the current point, and N represents the total length of the window (that is, the total number of sampling points).

[0035] Hamming window function:

[0036] Where n represents the index position of the current point, and N represents the total length of the window (that is, the total number of sampling points).

[0037] Fibonacci window function:

[0038] Here, k is the item index, equivalent to n in the previous example, and m is the modulus, which is used to control the range of values ​​and map the Fibonacci numbers to a reasonable density range.

[0039] Fibonacci sequence distribution function:

[0040] Where k represents the item number index.

[0041] As an optional solution, the photon sieve arrangement can be monofocal or bifocal; monofocal means the photon sieve arrangement satisfies a single window function; bifocal means the photon sieve arrangement satisfies two window functions simultaneously. Bifocal involves overlapping two photon sieves with different focal lengths to form a partially overlapping sieve aperture. A monofocal photon sieve design can stably provide myopia-correcting defocus, and when combined with the emmetropic signal provided by the central optical correction zone, a bifocal design can be used to simultaneously provide both emmetropic and myopia-correcting defocus signals.

[0042] As an optional solution, the light transmittance of the defocus area and the edge arc area is lower than that of the optical correction area; preferably, the defocus area and / or the edge arc area are opaque components. Using opaque components in the defocus area and / or the edge arc area reduces projection and facilitates the creation of a low-contrast environment on the retina; the edge arc area is farther from the central optical correction area and does not affect the entrance pupil light. Preferably, the defocus area and / or the edge arc area can be made of opaque materials, achieved through opaque coatings, photolithography, deposition, molding, printing, or machine processing, while the optical correction area is made of transparent materials.

[0043] As an optional design, the diameter of the photon sieve is 1~5 mm, specifically 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm. Preferably, the photon sieve is a micro-nano transparent aperture. The diameter of the optical correction area is 1~7 mm, specifically 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, or 7 mm; the diameter of the edge arc area is 1~5 mm, specifically 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

[0044] As an optional solution, the minimum size of the aperture of the photon sieve is larger than the wavelength of visible light, wherein the wavelength of visible light is 380 nm to 750 nm; as a preferred option, the wavelength of visible light may be 380 nm, 420 nm, 450 nm, 475 nm, 492 nm, 546 nm, 570 nm, 585 nm, 590 nm, 610 nm, 625 nm, or 740 nm.

[0045] As an optional solution, the photon-screen myopia control lens can be a soft contact lens, a rigid contact lens, a spectral lens, or an intraocular lens. Preferably, the base material of the photon-screen myopia control lens is a silicone hydrogel, hydrogel, fluorosilicone acrylate, or acrylate.

[0046] As an optional solution, combined with Figure 2 The size of the aperture and the number of rings are determined based on the focal length using the formula mentioned above: Distance from the center of the aperture to the center of the photon sieve plane Satisfying equation (Ⅰ) (I) In formula (Ⅰ) For the incident light wavelength, For focal length, This refers to the number of individual holes in a single ring on a concentric ring. Small hole diameter Satisfying equation (II) (II) In formula (II) This is the proportionality coefficient, and the value used is 1.5; Total number of rings on concentric rings N Satisfying equation (Ⅲ) (III) In formula (Ⅲ) This indicates the aperture of the photon sieve.

[0047] When the minimum diameter of the aperture in the photon sieve is greater than the wavelength of the incident light When the polarization properties of the incident light are neglected, the paraxial far-field focusing of the photon sieve can be analyzed using scalar diffraction theory.

[0048] like Figure 3 The photon sieve diffraction model is constructed as shown. A coordinate system XYZ is established at the center of the photon sieve, with the optical axis in the Z direction and the plane coordinates in the XY direction. The complex amplitude of the incident light field is... According to the Fresnel diffraction integral formula, the photon sieve... The light field at point P(X,Y) in image space of the small aperture is: Satisfying equation (Ⅳ) (IV) The distribution of the complex amplitude of the incident light field at the nth aperture, neglecting the phase factor. , satisfying equation (V) (V) The area of ​​the aperture is very small, and the change in the light field within the aperture is very small, so it can be considered as a local plane wave. The complex amplitude of the incident light field is simplified and satisfies equation (VI). (VI) in , The coordinates of the center of the small hole, The amplitude of the light field at the center of the aperture. , ,

[0049] Among them, g n and h n It is function L n At the center point of the hole (x) n ,y n The partial derivative at ) is the projection of the wave vector k of the light wave onto the x and y directions. k is the angular wave number of the light wave, k = 2π / λ, which represents the change in phase per unit length during the propagation of the wave.

[0050] The actual light field on the image plane is composed of the superposition of numerous diffracted light fields from the pinholes. Therefore, the light field distribution of the entire photon sieve on the image plane is as follows: , satisfying equation (VII) (VII) in It is the number of all the small holes on the photon sieve. When parallel light is incident perpendicularly, ; The formula satisfies equation (VIII). (VIII) Example 2 The present invention also provides a design method for the photon-screen myopia control lens of Embodiment 1 above, comprising the following steps: S1. Determine the photon sieve parameters: based on the focal length The distances from the center of the aperture to the center of the photon sieve plane are obtained sequentially using formulas (I) to (III). Small hole diameter The total number of rings on concentric rings N The aperture distribution of the photon sieve is modulated by the above-mentioned window function. In this embodiment, the Fibonacci sequence distribution function is preferably used as the window function. S2. Prepare a photon sieve that meets the above parameters in the defocus region.

[0051] After determining the distribution of photon sieve apertures, the apertures distributed in the photon sieve region are retained, while those distributed in the central optical correction area and the edge arc area are discarded, so that they are only distributed in the defocus area, which is the final photon sieve. The photon sieve structure is formed in the defocus area of ​​the myopia control lens through opaque coating, photolithography, deposition, molding, printing or machining. The radius of curvature of the central optical correction area and the edge arc are obtained by sequentially using optical power and refractive index, resulting in a dry-state refractive-diffractive hybrid soft lens. Alternatively, the film layer of the photon sieve structure can be directly attached to the dry-state refractive soft lens after lathe machining or molding through molding or photolithography, followed by hydration, plasma, cleaning and other processes to obtain a wet-state refractive-diffractive hybrid soft lens, which is the photon sieve myopia control lens.

[0052] Specifically, based on a 14 mm aperture lens designed for a wavelength of 546 nm, a central optical correction zone diameter of 3 mm, and an optical power of -3 D, the photon sieve diameter is 2 mm. A single-focal optical design is adopted, with an optical power of +2 D. According to formulas (I) to (III), the total number of annular bands is calculated to be 179. When the number of annular bands is 1, the distance from the center of the aperture to the center of the photon sieve plane is 0.739 mm, and the aperture diameter is 0.28 mm. The aperture data for all annular bands are calculated in this manner. The distribution is simulated using MATLAB and modulated using a Fibonacci window function to obtain the final distribution map, as shown below. Figure 4 As shown, the portion distributed within the photon sieve diameter is retained, while the portions distributed in the central optical correction area and the edge arc area are discarded; the edge arc diameter is 2 mm.

[0053] Substituting the above parameters into equation (VIII) in Example 2, the light field distribution function is obtained. Spectral amplitude distribution (logarithmic) and radial average spectrum analysis are performed on the photon sieve region of the obtained photon sieve myopia control lens. The analysis results are shown in Figure 5. Figure 6 As shown in the graph, the photon sieve modulated by the Fibonacci window function in this photon sieve myopia control lens has the characteristics of suppressing side lobes and improving resolution.

[0054] Example 3 1. Testing Method (1) A window function modulated photonic sieve was prepared according to the method of Example 2, and the middle optical correction region was added to the photonic sieve structure. The point distribution of the middle part of the photonic sieve has been removed. The resulting photonic sieve aperture distribution is modulated by the window functions of triangular window, rectangular window, Hamming window and Fibonacci function in sequence. Then, the feasibility of modulating photonic sieves with different window functions is analyzed.

[0055] (2) Test Example 2 and Fresnel diffraction lens light field distribution function, and test the normalized spectral intensity distribution under the same myopia control lens.

[0056] 2. Test Results Window function modulation photon sieve results are as follows Figure 7 As shown, by Figure 7 Triangular windows (a), rectangular windows (b), Hamming windows (c), and Fibonacci functions (d) can all modulate photon sieves. These window functions exhibit varying degrees of sidelobe suppression effectiveness, with the Fibonacci function showing the best results, achieving excellent sidelobe suppression similar to complex random structures or multi-order phase structures while maintaining high-quality main focal points. Hamming windows further suppress the first sidelobe by adjusting coefficients. However, they also face the challenge of optimizing the intensity of sidelobes in the continuous spectrum, rather than the discrete diffraction orders. For discrete aperture structures like photon sieves, Hamming windows can reduce but not eliminate higher-order diffraction focal points, which still exist in a regular pattern.

[0057] like Figure 8 Compared with Fresnel lenses Figure 8 (b) The myopia control lens prepared in Example 2, after being modulated by a window function, suppressed the secondary diffraction maxima on both sides of the main diffraction maxima. Figure 8 (a) The intensity of the diffraction submaximum is significantly weaker than that of the main maximum, which reduces the sidelobe effect, weakens the background noise, and provides better optical quality. At the same time, since the photon sieve design is composed of opaque small holes, it can provide a low contrast environment for the retina, further enhancing the myopia control effect.

[0058] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

Claims

1. A myopia prevention control lens, characterized in that, The myopia prevention and control lens comprises a lens body, wherein an optical correction area, a defocus area and a peripheral curve area are concentrically arranged on the lens body; the defocus area is arranged between the optical correction area and the peripheral curve area, and the defocus area is provided with a photon sieve composed of a series of small holes distributed on a concentric ring, and the small holes are arranged to satisfy a window function; and the light transmittance of the defocus area is lower than that of the optical correction area.

2. The myopia control phoropter of claim 1, wherein, The window function is selected from one of a triangular window function, a rectangular window function, a Hamming window function, a Hanning window function, a Gaussian window function, a Fibonacci sequence distribution function or a combination thereof.

3. The myopia control phoropter of claim 1, wherein, The photon sieve is arranged to be single focus or double focus; the single focus is that the photon sieve arrangement satisfies a single window function; and the double focus is that the photon sieve arrangement satisfies two window functions at the same time.

4. The myopia control phoropter of claim 1, wherein, The defocus area and / or the peripheral curve area are non-light-transmitting components.

5. The myopia control phoropter of claim 1, wherein, The radial width of the photon sieve is 1-5 mm.

6. The myopia control phoropter of claim 1, wherein, The diameter of the optical correction area is 1-7 mm; and the radial width of the peripheral curve area is 1-5 mm.

7. The myopia control phoropter of claim 1, wherein, The minimum size of the small holes of the photon sieve is greater than the wavelength of visible light, preferably; and the wavelength is 546 nm.

8. The myopia control phoropter of claim 1, wherein, The myopia prevention and control lens is a soft contact lens, a hard contact lens, a frame lens or an intraocular lens.

9. The myopia control phoropter of claim 1, wherein, The photon sieve satisfies: Distance of the center of the aperture to the center of the plane of the photon sieve satisfies equation (I) （Ⅰ） In formula (I) is the wavelength of the incident light, is the focal length, is the number of individual pinholes for one annular zone on the concentric circular ring; Orifice diameter satisfies formula (II) （Ⅱ） In formula (II) is a proportionality factor, most commonly used value is 1.2~1.8; Total number of annular bands on concentric circular rings N satisfy equation (III) （Ⅲ） In formula (III) denotes the aperture of the photon sieve.

10. The method of designing myopia control lenses of claim 1, wherein, The method comprises the following steps: S1. Determine the photon sieve parameters: according to the focal length The distance from the center of the pinhole to the center of the photon sieve plane is obtained in turn , the pinhole diameter , and the total number of annular rings on the concentric circle N ; and modulate the pinhole distribution of the photon sieve by the window function; S2. Preparing a photon sieve satisfying the above parameters in the defocus area. S2. Preparing a photon sieve satisfying the above parameters in the defocus area.

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