A method for manufacturing a reinforced multifocal polyurethane lens

Abstract

The present invention relates to a method for manufacturing a reinforced multifocal polyurethane lens. The surface shape of the lens adopts a four-layer circular area design, wherein the diameter of the circular area of ​​the first layer is in the range of 2.5-7.5 mm, the diameter of the circular area of ​​the second layer is in the range of 2.6-15 mm and does not include the first area; the diameter of the circular area of ​​the third layer is in the range of 2.7-30 mm and does not include the first area and the second area; the lens excluding the first area, the second area and the third area is collectively referred to as the fourth area; the present application adopts a four-layer light-adding strategy, so that the light addition increases according to a certain gradient, thereby improving wearing comfort; a discontinuous light-adding strategy is adopted in the first area, so that light entering the eyeball of a myopic patient can be more effectively imaged in front of the retina, forming an effective discontinuous myopic defocus, which makes it more effective to delay the progression of myopia in adolescents.

Description

Technical Field

[0001] The present invention relates to the technical field of lenses, in particular to a method for manufacturing a reinforced multi-focal polyurethane lens. Background Art

[0002] The "China Compulsory Education Quality Monitoring Report" released in 2018 by the Ministry of Education's Basic Education Quality Monitoring Center shows that my country's youth myopia rate is already the highest in the world, exceeding 70% among middle school, high school, and university students. This compares to approximately 25% for American adolescents, just 1.3% in Australia, and consistently below 15% in Germany. This isn't a static indicator; the myopia rate is still rising across China. If left unchecked, the myopia rate among elementary school students might not be 38% by 2030, but could be in the high 40s. Therefore, even a 0.5% annual reduction is still very difficult.

[0003] Research and exploration into the treatment of myopia are ongoing. Advances in understanding the mechanisms of myopia development, such as accommodation theory, defocus theory, and new findings at the molecular level of ocular biology, are providing new insights into its treatment and prevention. Currently, effective myopia correction methods, such as laser surgery, involve laser ablation of the cornea to create a concave lens, replacing the function of glasses. Much like wearing contact lenses, corneal ablation cannot be done casually; strict requirements apply to the degree of myopia and age. Furthermore, common postoperative complications such as dry eyes, glare, and myopia relapse can be devastating. Orthokeratology (OK) lenses for myopia correction utilize the natural pressure of the eyelids to alter corneal curvature, improving vision and offering relatively significant results. However, because they are often made of hard, hydrophobic materials, they can feel a strong foreign body sensation when worn. Furthermore, myopia reverts once removed. Furthermore, long-term wear of OK lenses can cause dry eyes, soreness, and inflammation in some wearers.

[0004] Frame glasses utilize single vision concave lenses, bifocal concave lenses, and progressive multifocal lenses, along with peripheral defocused frame lenses to control the progression of myopia. Chinese Patent: CN208921990U Title: A lens and glasses capable of controlling the progression of myopia. The lens comprises an upper lens and a lower lens, each having a higher refractive power than the lower lens. The upper and lower lenses are connected by respective connecting surfaces, and the adjacent side surfaces of the upper and lower lenses are connected to form smooth curved surfaces. This lens and glasses can control the rapid progression of myopia. Chinese Patent: CN202339453U, title: A pair of special glasses for controlling myopia and reducing myopia, comprising a frame and lenses fixed to the frame. The lenses are designed based on the multifocal principle, have a compact structure, and have multiple functions. They are primarily suitable for adolescents and can eliminate visual fatigue, effectively control the development of true myopia, improve vision, restore early myopia, and treat moderate and low myopia. The different optical focal points of the lens' progressive zone can stimulate the human eye's visual cells, thereby exercising the visual function and having a significant effect on amblyopia in young children. Experimental studies have shown that the control of myopia with single-vision concave lenses, bifocal concave lenses, and progressive multifocal lenses is very limited.

[0005] This patent provides a method for manufacturing a reinforced multifocal polyurethane lens. The lens surface features a four-layer circular zone design. The first zone has a diameter ranging from 2.5 to 7.5 mm. The second zone has a diameter ranging from 2.6 to 15 mm and excludes the first zone. The third zone has a diameter ranging from 2.7 to 30 mm and excludes the first and second zones. The lens, excluding the first, second, and third zones, is collectively referred to as the fourth zone. The first zone has two diopters, the diopters of which are based on the prescription used to correct refractive errors. The lens features multiple independent raised domes distributed across the surface, each adding +0.25 to +1.00 D of light compared to the planar diopters. The second zone has two diopters, the diopters of which are based on the prescription used to correct refractive errors. The lens features multiple independent raised domes distributed across the surface, each adding +0.50 to +2.00 D of light compared to the planar diopters. The third area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct refractive errors of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.75-+4.00D compared to the flat diopters. The fourth area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct refractive errors of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +1.00-+5.00D compared to the flat diopters. The four-layer light-adding strategy is adopted, so that the light addition increases according to a certain gradient, which improves the wearing comfort. The discontinuous light-adding strategy is adopted in the first area, so that the light entering the eyeball of the myopic patient can be more effectively imaged in front of the retina, forming an effective discontinuous myopic defocus, which makes it more effective to delay the deepening of myopia in adolescents. Summary of the Invention

[0006] The object of the present invention is to overcome the deficiencies of the prior art and provide a method for manufacturing a reinforced multifocal polyurethane lens, where PRO is the abbreviation for reinforced.

[0007] The object of the present invention is achieved through the following technical solutions:

[0008] A method for manufacturing a reinforced multifocal polyurethane lens, characterized in that the surface of the lens adopts a four-layer circular area design.

[0009] The diameter of the first layer area is in the range of 2.5-7.5 mm, preferably 5 mm;

[0010] The diameter of the second layer area is in the range of 2.6-15 mm and does not include the first area; preferably 10 mm;

[0011] The diameter of the third layer area is in the range of 2.7-30 mm and does not include the first area and the second area; preferably 20 mm;

[0012] The lens, in addition to the first, second and third areas, is collectively referred to as the fourth area;

[0013] The polyurethane lenses are round with a diameter of 50 mm to 100 mm.

[0014] Each area has two diopters. The diopters on the surface are based on the prescription diopters used to correct refractive errors of vision. There are independent raised domes distributed on the surface. The diopters of the raised domes are +0.25-+5.00D of light addition. The design of the raised domes is a high-order aspherical design:

[0015]

[0016] d is the correction coefficient; c is the curvature; r is the radius value; k is the quadratic surface coefficient; a2, a3, a4, a5, and a6 are high-order aspheric coefficients.

[0017] The first area has two diopters. The diopter on the surface is based on the diopter of the prescription used to correct the refractive error of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.25-+1.00D than the flat diopters.

[0018] The second area has two diopters. The diopter on the surface is based on the diopter of the prescription used to correct the refractive error of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.50-+2.00D than the flat diopters.

[0019] The third area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct the refractive error of the vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.75-+4.00D than the plane diopters.

[0020] The fourth area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct the refractive error of the vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +1.00-+5.00D than the plane diopters.

[0021] The lens material is polyurethane, and its refractive index and Abbe number meet the following requirements: refractive index 1.67 + Abbe number ≥ 30, or refractive index 1.60 + Abbe number ≥ 40, or refractive index 1.53 + Abbe number ≥ 58. The diameter of each raised top circle ranges from 0.05mm to 1.5mm, the height ranges from 0.10μm to 3.0μm, and the distance between two adjacent raised top circles ranges from 0.05mm to 1.5mm.

[0022] Compared with the prior art, the present invention has the following positive effects:

[0023] The four-layer light-adding strategy creates a gradient of light addition, improving wearing comfort. A discontinuous light-adding strategy is used in the first zone, allowing light entering the myopic eye to more effectively form an image on the retina, creating an effective discontinuous myopic defocus pattern, which is more effective in delaying the progression of myopia in adolescents. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a reinforced multifocal polyurethane lens. DETAILED DESCRIPTION

[0025] The following provides a specific embodiment of a method for manufacturing a reinforced multifocal polyurethane lens according to the present invention.

[0026] Example 1

[0027] Please see the attached Figure 1 The lens has a refractive index of 1.60, an Abbe number of 41, and a power of -4.00D. The 1.60 refractive index raw material is injected into a mold and cured. After curing, it undergoes demolding, edging, cleaning, hardening, laminating, and inspection to produce the desired semi-finished blank lens. A reinforced multifocal polyurethane lens is processed in a laboratory facility and tested for an actual power of -4.01D. The lens surface features a four-layer circular area design. The first layer has a diameter of 0.6mm. The second layer has a diameter of 1.2mm and excludes the first area. The third layer has a diameter of 2.4mm and excludes the first and second areas. The lens, excluding the first, second, and third areas, is collectively referred to as the fourth area. The first area has two diopters, the diopters based on the prescription for correcting refractive errors. Multiple independent raised domes are distributed across the surface, each with a +0.50D of added power compared to the flat diopters. The second zone has two diopters, with a total diopter of -4.00D. The surface is covered with multiple independent raised domes, which add +2.00D of light compared to the flat surface. The third zone has two diopters, with a total diopter of -4.00D. The surface is covered with multiple independent raised domes, which add +3.50D of light compared to the flat surface. The fourth zone has two diopters, with a total diopter of -4.00D. The surface is covered with multiple independent raised domes, which add 5.00D of light compared to the flat surface. This meets the requirements.

[0028] Example 2

[0029] Please see the attached Figure 1The lens has a refractive index of 1.67, an Abbe number of 30, and a power of -8.00D. The 1.67 refractive index raw material is injected into a mold and cured. After curing, it undergoes demolding, edging, cleaning, hardening, laminating, and inspection to produce the desired semi-finished blank lens. A reinforced multifocal polyurethane lens is processed in a laboratory facility and tested for an actual power of -8.07D. The lens surface features a four-layer circular area design. The first layer has a diameter of 0.6mm. The second layer has a diameter of 1.5mm and excludes the first area. The third layer has a diameter of 3.0mm and excludes the first and second areas. The lens, excluding the first, second, and third areas, is collectively referred to as the fourth area. The first area has two diopters, the diopters based on the prescription for correcting refractive errors. Multiple independent raised domes are distributed across the surface, each with a +1.00D addition compared to the flat diopters. The second zone has two diopters, with a total diopter of -8.01D. It features multiple independent raised domes, adding +2.00D of light compared to the flat diopters. The third zone has two diopters, with a total diopter of -7.99D. It features multiple independent raised domes, adding +4.00D of light compared to the flat diopters. The fourth zone has two diopters, with a total diopter of -7.91D. It features multiple independent raised domes, adding 5.00D of light compared to the flat diopters. This meets the requirements.

[0030] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the concept of the present invention. These improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for manufacturing a reinforced multifocal polyurethane lens, characterized in that: The surface of the lens adopts a four-layer circular area design. The diameter of the circular shape in the first layer ranges from 2.5 to 7.5 mm; The diameter of the second layer of regions ranges from 2.6 to 15 mm and does not include the first region; The diameter of the third layer area is in the range of 2.7-30 mm and does not include the first and second areas; The lens, in addition to the first, second and third areas, is collectively referred to as the fourth area; Each area has two diopters. The diopters on the surface are based on the prescription diopters used to correct refractive errors of vision. There are independent raised domes distributed on the surface. The diopters of the raised domes are +0.25-+5.00D of light addition. The design of the raised domes is a high-order aspherical design: d is the correction coefficient; c is the curvature; r is the radius value; K is the quadratic surface coefficient; a2, a3, a4, a5, a6 are high-order aspheric coefficients; The diameter of each raised top circle is 0.05 mm to 1.5 mm; A four-layer light adding strategy is adopted to increase the light adding in a gradient.

2. The method for manufacturing a reinforced multifocal polyurethane lens according to claim 1, wherein: The raw material of the lens is polyurethane, and its refractive index and Abbe number meet the conditions: refractive index 1.67 + Abbe number ≥ 30 or refractive index 1.60 + Abbe number ≥ 40 or refractive index 1.53 + Abbe number ≥ 58.

3. The method for manufacturing a reinforced multifocal polyurethane lens according to claim 1, wherein: The first area has two diopters. The diopter on the surface is based on the diopter of the prescription used to correct the refractive error of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.25-+1.00D than the flat diopters.

4. The method for manufacturing a reinforced multifocal polyurethane lens according to claim 1, wherein: The second area has two diopters. The diopter on the surface is based on the diopter of the prescription used to correct the refractive error of vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.50-+2.00D than the flat diopters.

5. The method for manufacturing a reinforced multifocal polyurethane lens according to claim 1, wherein: The third area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct the refractive error of the vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +0.75-+4.00D than the plane diopters.

6. The method for manufacturing a reinforced multifocal polyurethane lens according to claim 1, wherein: The fourth area has two diopters. The diopters on the surface are based on the diopters of the prescription used to correct the refractive error of the vision. There are multiple independent raised domes distributed on the surface. The diopters of the raised domes have a light addition of +1.00-+5.00D than the plane diopters.

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