CN113253481A

CN113253481A - Spectacle lens with invisible microstructure

Info

Publication number: CN113253481A
Application number: CN202110507447.8A
Authority: CN
Inventors: 任建锋; 黄启泰; 倪颖; 颜蒙; 李春琦; 李林峰
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2021-05-10
Filing date: 2021-05-10
Publication date: 2021-08-13
Anticipated expiration: 2041-05-10
Also published as: CN113253481B

Abstract

The invention discloses an ophthalmic lens with a contact microstructure, which has an object-side surface and an eye-side surface, which includes a first refractive region with a first refractive power for correcting refractive errors of the eye; and a second refractive power A region having a different refractive power from the first refractive power and having a function of imaging an object on a position other than the retina of the eye to suppress the development of refractive error of the eye, characterized in that the second refractive region It is composed of a plurality of circular sub-regions distributed on the lateral surface of the eye, the diameter of each sub-region is 2mm-6mm, each sub-region has a plurality of annular etching grooves, and the width of the etching groove is 30-100 mm. microns, the distribution and depth of the etched grooves allow the sub-regions to form a micro-lens structure and provide a second refractive power. The invention can restrain the development of myopia without affecting the beauty of the spectacle lenses.

Description

Spectacle lens with invisible microstructure

Technical Field

The invention relates to an ophthalmic lens, in particular to an ophthalmic lens with a microstructure, in particular to an ophthalmic lens with a contact microstructure.

Background

Human eyes are crucial for human information acquisition, and statistically more than 80% of human information acquisition originates from the eyes. At present, various electronic screens are flooded in social life, which emit light with different intensities, and the daily use time of human eyes is longer and longer, so that the human eyes continuously generate ametropia, and the ametropia is increasing. According to incomplete statistics, over 80% of college students have refractive errors above 200 degrees.

On the basis of the refractive correction, functional spectacle lenses have emerged which have the function of inhibiting the ametropia of the human eye. For example, a lens having a concentric fresnel multifocal shape is provided, and a plurality of dioptric regions are concentrically arranged in the lens, and this lens has a function of focusing an image on the retina of the spectacles, and if a patient views an object using the lens for inhibiting myopia, the image of the object is formed on the retina, and an image is formed at a point in front of the retina, so that an effect of inhibiting the progression of myopia can be obtained by two images during visual observation.

Chinese patent CN 104678572B discloses an ophthalmic lens in which several small area lenses with a circular shape and a diameter of about 0.8mm to 2mm are arranged in different areas to form a second dioptric area. The progression of myopia is suppressed by an image obtained in front of the retina by the second dioptric region while visually distinguishing an image of the object formed by the first refractive power. Meanwhile, the second dioptric region is not formed in a circular region having a radius of 2.5mm to 10.0mm with the optical center of the spectacle lens as the center, in order to maintain sufficient visibility and obtain a good wearing feeling. In the above-described aspect, as seen from the examples, the small area lens of a circular shape for forming the second dioptric region is arranged on the object-side surface of the spectacle lens.

For ophthalmic lenses, as shown in fig. 1, there is an object side surface 1 and an eye side surface 2. In actual production, the eye-side surface 2 is a fixed spherical, aspherical or astigmatic surface, the object-side surface 1 is processed into, for example, a spherical, aspherical or progressive surface, and a small-area mirror in document CN 104678572B is also provided on the object-side surface 1. As a result, there are a plurality of small bumps or depressions on the surface of the ophthalmic lens to form the second dioptric zone, which results in the ophthalmic lens being aesthetically significant and affecting the visual appearance. Meanwhile, when the object side surface 1 is a progressive surface, the difficulty of designing and manufacturing the small-area lens is also increased, so that the structural design is not suitable for the progressive spectacle lens.

Disclosure of Invention

The present invention has an object to provide a spectacle lens having a contact microstructure which can suppress a continuous increase in ametropia of an eye, ensure sufficient visibility and a good wearing feeling, ensure the beauty of the spectacle lens, and can be suitably used for a progressive spectacle lens.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: an ophthalmic lens having a contact microstructure, having an object-side surface and an eye-side surface, comprising a first refractive area having a first refractive power based on a refractive error of the corrected eye; and a second dioptric region having a refractive power different from the first refractive power and having a function of imaging an object at a position other than a retina of the eye to suppress development of ametropia of the eye, the second dioptric region being composed of a plurality of circular sub-regions distributed on an eye-side surface, each sub-region having a diameter of 2mm to 6mm, each sub-region having a plurality of annular etched grooves, a width of the etched grooves being 30 to 100 micrometers, the distribution and depth of the etched grooves causing the sub-regions to form a microlens structure and provide the second refractive power.

In the above technical scheme, by engraving the annular groove, the two sides of the main focal plane are equally provided with the second focal planes simultaneously due to the interference imaging. The front and rear focal planes are equidistant from the main focal plane, and the energies of the front and rear focal planes are the same, thereby suppressing the progression of ametropia. The width of the etched groove is 30-100 micrometers, the etched groove cannot be seen by naked eyes, and the micro-lens etching groove has an attractive function and also has a micro-lens function.

In the above technical solution, the structure of the sub-region is determined by the following steps:

(1) according to the refractive index n of the lens, the radius of curvature r of the front and back surfaces₁、r₂Calculating to obtain an equivalent curvature radius r of a secondary region, wherein the primary focal length F is the focal length of a primary focal surface corresponding to the first refraction region, and the focal surface distance d is the distance between the primary focal surface and the secondary focal surface corresponding to the second refraction region;

(2) dividing the zone of the secondary region according to the diameter of the secondary region and the equivalent curvature radius r, wherein the method comprises the following steps:

a. dividing the curved surface of the secondary region by adopting a Fresnel zone plate-like mode according to the phase change of 2pi or pi to obtain 3-5 annular zones;

b. if the phase dividing unit is 2pi, the binarization is carried out by changing pi, the setting larger than pi is a base surface, and the area smaller than pi is etched to remove the pi phase depth; if the phase dividing unit is pi, the binarization needs to be carried out by changing pi/2, the area which is larger than pi/2 is set as a base surface, and the area which is smaller than pi/2 is etched to remove the pi/2 phase depth;

c. and adjusting the etching width to ensure that the width of the etching groove is 30-100 microns, and completing the division of the girdle band of the secondary area.

In the above technical solution, within the range of the distribution of the sub-regions, the first dioptric region and the second dioptric region form a mixed region, wherein the area of the second dioptric region formed by the sub-regions is 20% to 60% of the total area of the mixed region.

In a preferred embodiment, the area of the second refraction zone formed by the sub-zones is 30 to 40 percent of the total area of the mixed zone.

In a preferred embodiment, the sub-regions are uniformly distributed in the mixing region.

In a preferred embodiment, the eye-side surface is a spherical surface, and the object-side surface is a spherical surface, an aspherical surface, or a progressive surface.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

1. the invention sets the sub-area for forming the second dioptric area on the surface of the eye side, so that the spherical surface can be selected for the surface of the eye side, the design and the processing are convenient to realize, and the shape design of the object side surface is not influenced, so that the invention can be suitable for the application occasions of progressive spectacle lenses;

2. the invention forms an equivalent micro-lens structure through the annular groove, the width of the groove is not more than 100 microns, the groove is difficult to distinguish by naked eyes, and the appearance of the spectacle lens is not influenced while the development of myopia can be inhibited.

Drawings

FIG. 1 is a schematic view of the construction of an ophthalmic lens;

FIG. 2 is a schematic diagram of the optical path of the embodiment;

FIG. 3 is a schematic diagram showing a design process of a sub-area in the embodiment;

FIG. 4 is a schematic diagram of a design process of a sub-region in another embodiment.

Wherein: 1. an object-side surface; 2. the eye-side surface.

Detailed Description

The invention is further described with reference to the following figures and examples:

the first embodiment is as follows: an ophthalmic lens having a contact microstructure, as shown in fig. 1, has an object side surface 1 and an eye side surface 2. For the eye-side surface 2, after the conventional spherical surface processing, a circular groove is engraved on the spherical surface, and after the groove is engraved, the two sides of the focal plane are equivalent to have the second focal planes simultaneously due to interference imaging. The distances between the front focal plane and the rear focal plane are equal to the distance between the main focal plane and the front focal plane, and the energies of the front focal plane and the rear focal plane are equal.

Referring to fig. 2, the main lens is a main lens of the lens, and the focal length thereof, i.e., the main focal length, is set to be F; the micro lens is a secondary lens, the focal length of the micro lens is set to be f, and the distance between a secondary focal plane and a primary focal plane is set to be d. Knowing the main focal length F and the focal plane difference d, the sub-focal length can be calculated.

The focal length of the lens is determined by the radius of curvature r of the two faces of the lens₁、r₂Thickness and refractive index n. The thickness of the glasses is very small, the distance between the glasses can be considered to be close to 0, and the focal length of the glasses can be written as

According to r₁，r₂And d, calculating the curvature radius r of the equivalent micro-lens in the secondary area by the refractive index of the lens. The calculation steps are as follows:

A. first according to r₁，r₂N, calculating the focal length F of the main lens;

B. calculating a secondary lens focal length F according to the primary lens focal lengths F and d;

C. according to r₁And calculating the curvature radius r of the second surface of the secondary lens according to the focal length f and the refractive index n of the secondary lens.

The radius of curvature r of the secondary mirror is thus obtained.

Example 1:

n =1.597 (nominal refractive index 1.6), 300 degrees myopia. The first face radius of curvature was 392.76mm, the second face radius of curvature was 131.2mm, and the center thickness was 1.2. A lens with a primary focal length of 330mm, a focal plane advancement of 10mm if required, and a secondary focal length of 320mm can be obtained, thus calculating a secondary radius of curvature of 128.5 mm. If a focal plane advancement of 20mm is required, the calculated minor radius of curvature is 125.8 mm.

Example 2:

n =1.499 (nominal refractive index 1.49), 400 degrees of myopia. The radius of curvature of the first face is 457.8mm, the radius of curvature of the second face is 98mm, the center thickness is 1.2mm, and the focal length of the lens is calculated to be 249.9mm, and if a focal plane 10mm back is desired, the radius of curvature is 104.07 mm. If a 40mm back-shift of the focal plane is required, a radius of curvature of 109.9mm is calculated. If a 100mm back shift is required, the minor radius of curvature is calculated to be 126.4 mm.

Example 3:

n =1.499 (nominal refractive index 1.49), 400 degrees of myopia. The radius of curvature of the first face was 457.8mm, the radius of curvature of the second face was 98mm, and the center thickness was 1.2. A lens focal length of 249.9mm and if a focal plane advancement of 40mm is required, a secondary focal length of 209.9mm can be obtained, thus calculating a secondary radius of curvature of 85.24 mm.

After obtaining the secondary curvature radius, the zone division and groove width setting of the secondary region are performed to determine the structure of the secondary region.

The method comprises the following steps:

A. the division is done according to the phase change 2pi (2 pi), which is handled as a fresnel zone plate.

B. If the turns of the 2pi phase division are changed too few, the division can be done on a pi basis. Generally, at least 3-5 ring bands are required to form interference images.

C. If the phase dividing unit is 2pi, the binarization needs to be carried out by changing pi, the area which is larger than pi is set as a base surface, and the area which is smaller than pi is etched to remove the pi phase depth. If the phase dividing unit is pi, the binarization needs to be carried out by changing pi/2, the area which is larger than pi/2 is set as a base surface, and the area which is smaller than pi/2 is etched to remove the pi/2 phase depth.

D. According to the above step processing, a duty ratio similar to 50% is obtained. According to the definition of diffraction optics, the duty ratio only changes the diffraction efficiency and does not change the phase, namely, the duty ratio is adjusted, the focal length is not influenced, and only the energy is influenced. The etch width is adjusted to be between 30 and 100 microns (where the entire face needs to be calculated so that the width of all the loops is uniform for ease of fabrication). The line width of the film with the thickness of more than 100 microns can be easily acquired by human eyes, and the invisible effect is avoided.

Referring to fig. 3, the process of zone division and groove width setting for the spectacle lens of example 3 is performed by the above method.

In example 3, the calculated minor radius of curvature was 85.24 mm. The phase is changed by 2pi, and the thickness d =0.55um/(1.499-1) =1.1 um. That is, when the difference in thickness is 1.1 μm, division into one turn is required. Assuming a circular zone diameter of 3mm, the sagittal height difference is 1.7 microns, considering a 1.1 micron change of 2pi, the division needs to be finer, i.e. 0.55 micron divides one turn, i.e. 1.7/0.55=3 turns can be divided within the entire 3mm diameter. In this case, the interference diffraction condition can be satisfied.

Fig. 4 is a schematic diagram of a setup process according to another embodiment. The calculated minor radius of curvature is 65.24 mm. The phase is changed by 2pi, and the thickness d =0.55um/(1.499-1) =1.1 um. That is, when the difference in thickness is 1.1 μm, division into one turn is required. Assuming a circular zone diameter of 3mm, the sagittal height difference is 4.2 microns, taking into account 0.55 micron for one revolution, i.e. 4.2/0.55=7 revolutions for the entire 3mm diameter.

Claims

1. An ophthalmic lens having a contact microstructure, having an object-side surface and an ocular-side surface, comprising a first refractive region having a first refractive power based on correcting refractive errors of the eye; and a second refractive region, Having a refractive power different from the first refractive power, and having a function of imaging an object on a position other than the retina of the eye to suppress the development of refractive error of the eye, characterized in that the second refractive region is distributed by A plurality of circular sub-regions are formed on the lateral surface of the eye, the diameter of each sub-region is 2 mm to 6 mm, each sub-region has a plurality of annular etching grooves, and the width of the etching groove is 30 to 100 microns, The distribution and depth of the etched grooves allow the sub-regions to form a microlens structure and provide a second refractive power.

2. The spectacle lens with invisible microstructure according to claim 1, wherein the structure of the sub-region is determined by the following steps:

(1) According to the refractive index n of the lens, the curvature radii r ₁ , r ₂ of the front and rear surfaces, the main focal length F, and the focal plane distance d, calculate the equivalent curvature radius r of the sub-region, where the main focal length F corresponds to the first refractive region The focal length of the main focal plane, the focal plane distance d is the distance between the main focal plane and the secondary focal plane corresponding to the second refractive region;

(2) According to the diameter of the sub-region and the equivalent radius of curvature r, divide the annular zone of the sub-region as follows:

a. First, use the Fresnel-like zone plate method on the surface where the sub-region is located, and divide it according to the phase change of 2π or π to obtain 3 to 5 annular zones;

b. If the phase division unit is 2π, you need to change π for binarization, set the value greater than π as the base surface, and etch away the π phase depth in the area smaller than π; if the phase division unit is π, you need to change π/2 is binarized, the area greater than π/2 is set as the base surface, and the area smaller than π/2 is etched away by π/2 phase depth;

c. Adjust the etching width so that the width of the etching groove is 30-100 microns, and complete the division of the annular zone of the sub-region.

3. The spectacle lens with contact microstructures according to claim 1, characterized in that: within the distribution range of the sub-regions, the first refractive region and the second refractive region form a mixed region, wherein the sub-regions are The area of the second refraction area constituted by the area is 20% to 60% of the total area of the mixed area.

4 . The spectacle lens with invisible microstructures according to claim 3 , wherein the area of the second refractive region formed by the sub-regions is 30% to 40% of the total area of the mixed region. 5 .

5 . The ophthalmic lens with invisible microstructures according to claim 3 , wherein the sub-regions are uniformly distributed in the mixed region. 6 .

6 . The spectacle lens with invisible microstructure according to claim 1 , wherein the eye-side surface is a spherical surface, and the object-side surface is a spherical surface, an aspherical surface or a progressive surface. 7 .