CN-121978786-A - Multilayer fusion type planar optical lens structure and integrated forming method

CN121978786ACN 121978786 ACN121978786 ACN 121978786ACN-121978786-A

Abstract

The invention discloses a multilayer fusion type plane optical lens structure and an integrated forming method, belonging to the technical field of sampling devices; the optical fiber comprises a gradient refractive index transition layer, a microstructure functional layer, a stress self-compensating intermediate layer and a transparent hard protective layer, wherein interface fusion is realized among the gradient refractive index transition layer, the microstructure functional layer, the stress self-compensating intermediate layer and the transparent hard protective layer through chemical bonding or interpenetrating polymer network structure. The gradient refractive index transition layer realizes optical matching and mechanical buffering, realizes active stress balance through the stress self-compensating intermediate layer, realizes multi-layer fusion through a chemical bonding interface, realizes high-precision and high-efficiency manufacturing through an integrated forming process, eliminates interface reflection loss, remarkably improves light energy utilization efficiency, eliminates wavefront distortion caused by stress, remarkably improves imaging definition, improves interface bonding strength, and eliminates peeling risk.

Inventors

Mogadasi Motuba
LI JIAYI
SUN YUE
CAI XIAOGU
Di Make
WANG WEN
GONG SHIJIE
ZHAO ERSHUAI
LONG TAN
ZHANG CHI
ZHU ZHILIN

Assignees

南通诺瞳奕目医疗科技有限公司
北京诺瞳奕目医疗科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260326

Claims (14)

1. Multilayer fusion type plane optical lens structure, its characterized in that includes the range upon range of setting in proper order: a substrate bearing layer; The gradient refractive index transition layer forms a chemical bonding interface with the substrate bearing layer; a microstructure functional layer on which a diffraction or fresnel microstructure realizing prescribed optical power is provided; The stress self-compensating intermediate layer has a thermal expansion coefficient between the microstructure functional layer and the transparent hard protective layer, an elastic modulus between the microstructure functional layer and the transparent hard protective layer, and residual stress formed after curing and residual stress of the microstructure functional layer and the substrate bearing layer are balanced to ensure that the integral warping amount of the lens is less than or equal to 0.05 mm; a transparent hard protective layer; The gradient refractive index transition layer, the microstructure functional layer, the stress self-compensating intermediate layer and the transparent hard protective layer are subjected to interface fusion through chemical bonding or interpenetrating polymer network structure.
2. The multilayer fusion type planar optical lens structure according to claim 1, wherein the gradient refractive index transition layer is formed by at least two photocurable resin materials with different refractive indexes through a gradient coating or micro-layer coextrusion mode, and the refractive index distribution curve along the thickness direction is selected from one of linear distribution, index type distribution, S-type distribution or multi-stage distribution.
3. The multilayer fusion type planar optical lens structure according to claim 1, wherein the low refractive index component in the gradient refractive index transition layer is one or more of perfluoroalkyl acrylate, perfluoropolyether acrylate, trifluoroethyl methacrylate and organosilicon acrylate, and the high refractive index component is selected from sulfur-containing acrylate, fluorene-containing acrylate, bromine-containing acrylate or nanoparticle-doped acrylate.
4. The multilayer fusion type planar optical lens structure according to claim 1, wherein the thermal expansion coefficient of the stress self-compensating interlayer is 50-120 ppm/°c, the elastic modulus is 0.5-2.5 GPa, the thickness is 10 μm-30 μm, the curing shrinkage is 1.5% -4.0%, and the shrinkage stress generated after curing is 0.5-5 mpa.
5. The multilayer fusion type planar optical lens structure according to claim 1, wherein the stress self-compensating interlayer material is one or a mixture of polyurethane acrylic ester, polyether acrylic ester and epoxy acrylic ester, and a soft chain segment with the mass percent of 5% -25% is added, and the soft chain segment is one of polyethylene glycol, polycaprolactone or polytetrahydrofuran.
6. The multilayer fusion type planar optical lens structure according to claim 1, wherein the transparent hard protection layer is one of an organic-inorganic hybrid resin, a siloxane hard coating, a diamond-like film, a silicon nitride film or an aluminum oxide film, and the transparent hard protection layer and the stress self-compensating intermediate layer form interface fusion through covalent bonding or chemical bonding of an undercoat layer.
7. The multilayer fusion planar optical lens structure of claim 1, further comprising one or more of a first stress buffering sublayer disposed between the substrate carrier layer and the graded index transition layer, a second stress buffering sublayer disposed between the graded index transition layer and the microstructured functional layer, and a third stress buffering sublayer disposed between the stress self-compensating intermediate layer and the transparent hard protective layer.
8. The method for integrally forming a multilayer fusion planar optical lens structure according to any one of claims 1-7, comprising the steps of: Step one, carrying out surface activation treatment on a substrate bearing layer to enable the surface energy to be increased to 45-75 mN/m, and introducing active functional groups capable of participating in photo-curing reaction; Forming a gradient refractive index transition layer with refractive index continuously changing on the substrate bearing layer by means of gradient coating or micro-layer coextrusion, and performing ultraviolet curing to enable the transition layer and the substrate bearing layer to form chemical bonding; step three, forming a microstructure functional layer on the transition layer through ultraviolet nanoimprint; Forming a stress self-compensating intermediate layer on the microstructure functional layer, and controlling and regulating the curing stress of the intermediate layer through sectional illumination and temperature gradient control so as to balance the shrinkage stress generated by the intermediate layer and the residual stress of the lower layer; And fifthly, integrally forming a transparent hard protective layer on the stress self-compensating interlayer, wherein the protective layer and the interlayer interface undergo a crosslinking reaction to form chemical bonding.
9. The method of integrally forming a multi-layer fusion planar optical lens structure of claim 8, wherein said segmented illumination and temperature gradient control in step four comprises: The method comprises the steps of carrying out a first stage, namely, the illumination intensity is 5-15 mW/cm & lt 2 & gt, the temperature is 40-50 ℃ and the curing time is 30-90 s, a second stage, namely, the illumination intensity is 30-60 mW/cm & lt 2 & gt, the temperature is 60-90 ℃ and the curing time is 60-180 s, and adjusting the curing parameters through real-time feedback through online stress detection.
10. The method of claim 9, wherein the on-line stress detection includes one or more of laser triangulation of radius of curvature, birefringence measurement of stress distribution, shack-hartmann wavefront sensor of transmitted wavefront distortion, and the detected data is fed back to a curing control system to dynamically adjust illumination intensity and temperature to form closed loop control.
11. The method for integrally forming a multi-layer fusion type planar optical lens structure according to claim 8, wherein in the fourth step, for progressive addition lenses or free-form surface lenses with uneven microstructure density distribution, a digital micromirror device or a liquid crystal light valve is used to control the spatial distribution of illumination intensity, so that the area with higher microstructure density obtains higher illumination intensity.
12. The method for integrally forming a multilayer fusion type planar optical lens structure according to claim 8, wherein the materials of the gradient refractive index transition layer, the microstructure functional layer, the stress self-compensating intermediate layer and the transparent hard protective layer all contain active functional groups capable of participating in photocuring crosslinking reaction, and the active functional groups are one or more selected from acrylate double bonds, methacrylate double bonds, epoxy groups, hydroxyl groups and silicon hydroxyl groups.
13. The method for integrally forming a multilayer fusion type planar optical lens structure according to claim 8, wherein in the second step, the gradient coating is performed by using a two-channel or multi-channel slit coating head, the mixing ratio of the low refractive index component to the high refractive index component is controlled by a precise metering pump to change with time, and the thickness and refractive index distribution are monitored in real time during the coating process.
14. The method for integrally forming a multilayer fusion type planar optical lens structure according to claim 8, wherein in the third step, the ultraviolet nanoimprint is performed by using a nickel template or a quartz template, and a fluorosilane release layer is coated on the surface of the template.

Description

Multilayer fusion type planar optical lens structure and integrated forming method Technical Field The invention relates to the technical field of optical lenses, in particular to a multilayer fusion type plane optical lens structure and an integrated forming method. Background Optical lenses based on diffractive optical elements or fresnel microstructures utilize surface microstructures to achieve optical power, thereby compressing the lens body into a thin sheet structure, theoretically achieving a fully planarized appearance. However, such schemes still present the following systematic technical challenges in practical industrial applications: 1. The microstructure layer is exposed and easy to abrade and pollute, the feature size of the Fresnel microstructure is in the micron or even submicron level, the structure depth is usually 0.5-30 mu m, and the feature period is 2-200 mu m. When the microstructure is located on the surface or near surface of the lens, wiping, scraping, dust accumulation, sweat corrosion and the like in daily use all cause edge breakage, groove blockage, rapid reduction of diffraction efficiency and serious stray light problems. In the prior art, although there is a scheme of coating a protective layer on the surface of a microstructure, there is a refractive index difference between the protective layer and the microstructure layer, which can introduce additional phase error and damage the optical design accuracy of the microstructure. 2. In order to realize the protection of the microstructure, the prior art adopts a multi-layer bonding mode to bond and compound the microstructure functional layer and the protection layer through optical adhesive. However, differences in refractive index, coefficient of Thermal Expansion (CTE) mismatch, differences in elastic modulus, and cure shrinkage between the different layer materials can introduce complex residual stress distributions at the interface between layers and within the layers. Such stress mismatch causes problems of warp deformation, optical center shift, aberration introduction, and interfacial delamination. 3. The interface bonding reliability is insufficient and the manufacturing yield is low, the prior art adopts a step-by-step bonding mode, and each layer is assembled through optical cement after being independently formed. The process path has the inherent defects of poor alignment precision, accumulated multilayer stacking errors, difficult control of optical center and geometric center deviation, difficult complete elimination of interface bubbles and pollutants, and formation of scattering centers. 4. Optical loss due to abrupt refractive index changes in the multilayer structure, fresnel reflection losses occur from abrupt refractive index changes between every two adjacent layers. In the visible light band, the single interface reflectivity is about 4%, and for a 3-4-layer structure, the total transmittance loss can reach 10% -15%, so that the light energy utilization rate is seriously affected. Meanwhile, the multiple reflection can also form stray light on the image surface, and the image contrast is reduced. In view of the foregoing, there is a need for a lens structure and a method for manufacturing the same, which can realize an ultra-thin planar morphology, and which has high optical efficiency, high mechanical stability, no peeling risk at the interface, controllable stress, and suitable for mass production. Disclosure of Invention Aiming at the technical defects, the invention aims to provide a multilayer fusion type plane optical lens structure and an integrated forming method, wherein optical matching and mechanical buffering are realized by a gradient refractive index transition layer, active stress balance is realized by a stress self-compensating intermediate layer, multilayer fusion is realized by a chemical bonding interface, high-precision and high-efficiency manufacturing is realized by an integrated forming process, interface reflection loss is eliminated by setting the gradient refractive index transition layer, light energy utilization efficiency is obviously improved, wavefront distortion caused by stress is eliminated by setting the stress self-compensating intermediate layer, imaging definition is obviously improved, interface bonding strength is improved by setting a transparent hard protective layer, peeling risks are eliminated, and technical problems in the background art are solved. In order to solve the technical problems, the invention adopts the following technical scheme that the invention provides a multilayer fusion type plane optical lens structure, which comprises the following components in sequence in a laminated way: a substrate bearing layer; the gradient refractive index transition layer is characterized in that the refractive index of the gradient refractive index transition layer continuously changes along the thickness direction, and the change range is 0.05-0.35, and a che