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CN-122018175-A - Acrylic lens and production process thereof

CN122018175ACN 122018175 ACN122018175 ACN 122018175ACN-122018175-A

Abstract

The invention discloses an acrylic lens which comprises a lens substrate, an aspheric optical structure formed on at least one optical surface of the lens substrate, a hard coating, a multilayer antireflection film and an antifouling layer which are sequentially laminated and compounded on the surface of the aspheric optical structure, wherein the lens substrate is formed by a copolymer of methyl methacrylate and a high-refractive-index aromatic monomer, inorganic nano particles with the surfaces modified by a silane coupling agent are uniformly dispersed in the copolymer, the particle size of the inorganic nano particles is 5-20nm, the content of the inorganic nano particles accounts for 1% -5% of the total mass of the lens substrate, and the hard coating is a diamond-like carbon-based film formed by a plasma enhanced chemical vapor deposition method. By introducing aromatic rings and other structures into the lens matrix, the intrinsic refractive index of the material is improved, so that the thickness of the center and the edge of the lens is reduced under the same diopter, and the thinning and the light weight of the lens are realized.

Inventors

  • ZHAO SHENGXIANG
  • XIE YIXIN
  • ZHANG LINMING

Assignees

  • 惠州大唐伟业电子有限公司

Dates

Publication Date
20260512
Application Date
20260115

Claims (10)

  1. 1. An acrylic lens is characterized by comprising a lens substrate, an aspheric optical structure formed on at least one optical surface of the lens substrate, and a hard coating, a multilayer antireflection film and an antifouling layer which are laminated and compounded on the surface of the aspheric optical structure in sequence; The lens matrix is formed by a copolymer of methyl methacrylate and a high-refractive-index aromatic monomer, inorganic nano particles with the surfaces modified by a silane coupling agent are uniformly dispersed in the copolymer, the particle size of the inorganic nano particles is 5-20nm, and the content of the inorganic nano particles accounts for 1% -5% of the total mass of the lens matrix; the hard coating is a diamond-like carbon-based film formed by a plasma enhanced chemical vapor deposition method.
  2. 2. The acrylic lens according to claim 1, wherein the high refractive index aromatic monomer is at least one of styrene, methyl styrene or naphthalene acrylate, and the mass percentage thereof in the copolymer is 10% -30%.
  3. 3. The acrylic lens according to claim 1, wherein the inorganic nanoparticle is at least one of nano silica, nano zirconia or nano titania.
  4. 4. The acrylic lens according to claim 1, wherein the multi-layered antireflection film has a seven-layered film structure composed of alternating silica layers and titania layers, and the outermost layer is a silica layer.
  5. 5. The acrylic lens according to claim 1, wherein the antifouling layer is a film of perfluoropolyether or fluorosilane compound having a thickness of 5-15nm, such that the water contact angle of the lens surface is greater than 110 ° and the oil contact angle is greater than 70 °.
  6. 6. A process for the production of an acrylic lens according to any one of claims 1 to 5, comprising the following sequential steps: S1, material pretreatment and blending, namely uniformly mixing a dried methyl methacrylate monomer, a high-refractive-index aromatic monomer, surface-modified inorganic nano particles and an initiator, and performing prepolymerization to obtain a modified prepolymer; S2, precisely injection molding, namely injecting the modified prepolymer into a precisely temperature-controlled injection mold, wherein the mold cavity is provided with a preset aspheric surface, injection molding is carried out under the process conditions of 230-250 ℃ of a charging barrel, 80-90 ℃ of the mold and 80-120MPa of injection pressure, and then pressure maintaining, cooling and demolding are carried out to obtain a lens matrix blank with an aspheric optical structure; S3, annealing treatment, namely placing the lens matrix blank into a program temperature control oven, and performing step annealing to eliminate internal stress; S4, surface coating, namely sequentially depositing a hard coating on the surface of the aspherical optical structure of the lens matrix after plasma cleaning by a plasma enhanced chemical vapor deposition method, depositing a multi-layer antireflection film by a magnetron sputtering method and depositing an antifouling layer by a vacuum evaporation method.
  7. 7. The acrylic lens according to claim 6, wherein the mold core of the injection mold in step S2 is formed by single-point diamond turning, the surface precision PV value is less than 0.2 μm, and the surface roughness Ra is less than 10 nm.
  8. 8. The acrylic lens according to claim 6, wherein the step annealing in step S3 is performed by first maintaining the temperature at 80 ℃ for 2 hours, then cooling to 60 ℃ at a rate of 10 ℃ per hour, further maintaining the temperature for 2 hours, and finally cooling to room temperature with the furnace.
  9. 9. The acrylic lens according to claim 6, wherein in the step S4, when the hard coating is deposited, the plasma enhanced chemical vapor deposition is performed under the conditions that the substrate bias is-200V to-400V and the chamber pressure is 10-50Pa using methane and hydrogen as the reaction gas sources.
  10. 10. The acrylic lens according to claim 6, wherein in the pre-polymerization process of step S1, a supercritical carbon dioxide fluid is introduced into the mixed system, the supercritical carbon dioxide fluid has a pressure of 8-15MPa and a temperature of 40-60 ℃.

Description

Acrylic lens and production process thereof Technical Field The invention relates to the technical field of acrylic lenses, in particular to an acrylic lens. Background Acrylic lenses, namely optical lenses made from polymethyl methacrylate (PMMA) as a main raw material, are widely applied to the fields of spectacles, optical instruments, lighting equipment, display panels and various window protection due to the advantages of small density, high light transmittance (up to 92 percent or more), excellent processing performance, relatively low cost and the like. However, with the continuous development of optical products to high performance, light weight, durability and visual comfort, the inherent limitations of the traditional acrylic lens in terms of material performance, optical design, surface function and the like are increasingly highlighted, and the severe requirements of high-end application scenes are difficult to meet. The prior art mainly has the inherent defects of the comprehensive performance of the materials, such as low self hardness (pencil hardness is usually only about 2H), insufficient impact toughness, extremely easy scratch and even crack when being rubbed, scratched or accidentally bumped, durability far inferior to that of glass lenses, optical aberration and visual field limitation, most of traditional acrylic lenses adopting single spherical design, obvious spherical aberration and astigmatism generated by spherical lenses when correcting vision, especially at medium-high diopter, insufficient surface functional protection, limited (usually not more than 3H) hardness improvement of the coating by spraying or dip-coating ultraviolet curing type organic silicon hard coating, still not ideal abrasion resistance, possibly reduced adhesion with a matrix after long-term use or cold and hot circulation, almost simple single-layer or double-layer film plating in the aspect of antireflection treatment, limited reduction of reflectivity (more than 1.5% of residual reflectivity), incapacity of effectively eliminating glare, and poor spectral effect in a wide range. Disclosure of Invention Accordingly, it is necessary to provide an acrylic lens which solves the technical problems of the conventional acrylic lens, such as insufficient mechanical strength, optical performance, surface durability, and weight reduction. The acrylic lens comprises a lens matrix, an aspheric optical structure formed on at least one optical surface of the lens matrix, and a hard coating, a multilayer antireflection film and an antifouling layer which are sequentially laminated and compounded on the surface of the aspheric optical structure, wherein the lens matrix is formed by a copolymer of methyl methacrylate and a high-refractive-index aromatic monomer, inorganic nano particles with the surfaces modified by a silane coupling agent are uniformly dispersed in the copolymer, the particle size of the inorganic nano particles is 5-20nm, the content of the inorganic nano particles accounts for 1% -5% of the total mass of the lens matrix, and the hard coating is a diamond-like carbon-based film formed by a plasma enhanced chemical vapor deposition method. In one embodiment, the high refractive index aromatic monomer is at least one of styrene, methyl styrene or naphthalene acrylate, and the mass percentage of the high refractive index aromatic monomer in the copolymer is 10% -30%. In one embodiment, the inorganic nanoparticle is at least one of nanosilica, or nanosilica. In one embodiment, the multi-layer antireflection film is a seven-layer film structure formed by alternately forming a silicon dioxide layer and a titanium dioxide layer, and the outermost layer is the silicon dioxide layer. In one embodiment, the antifouling layer is a film formed by perfluoropolyether or fluorosilane compounds, the thickness of the antifouling layer is 5-15nm, so that the water contact angle of the surface of the lens is more than 110 degrees, and the oil contact angle is more than 70 degrees. The production process for preparing the acrylic lens comprises the following sequential steps: S1, material pretreatment and blending, namely uniformly mixing a dried methyl methacrylate monomer, a high-refractive-index aromatic monomer, surface-modified inorganic nano particles and an initiator, and performing prepolymerization to obtain a modified prepolymer; S2, precisely injection molding, namely injecting the modified prepolymer into a precisely temperature-controlled injection mold, wherein the mold cavity is provided with a preset aspheric surface, injection molding is carried out under the process conditions of 230-250 ℃ of a charging barrel, 80-90 ℃ of the mold and 80-120MPa of injection pressure, and then pressure maintaining, cooling and demolding are carried out to obtain a lens matrix blank with an aspheric optical structure; S3, annealing treatment, namely placing the lens matrix blank into a program temperature control oven, and p