Composite film layer structure

Abstract

The present invention provides a composite film layer structure. The composite film layer structure comprises a substrate, and an intermediate layer, a first low reflection film layer, and a second low reflection film layer which are sequentially coated on the substrate. The equivalent refractive index of the second low reflection film layer is less than that of the first low reflection film layer. When the angle of incidence is 0°, the average reflectivity of the composite film layer structure in a waveband of 380-980 nm is less than 0.1%, so that the composite film layer structure has the characteristics of ultralow reflectivity and low scattering, and the problem of fogging in real photography is effectively solved, significantly improving the image quality.

Description

Composite membrane structure

Technical field

[0001] The present invention relates to the technical field of optical lens coating, and in particular to a composite film layer structure. [Background Technology]

[0002] In recent years, with the rapid advancement of technology, users have increasingly demanded higher image quality from cameras in portable electronic devices, leading to continuous breakthroughs and innovations in lens coating technology. Some portable electronic devices have adopted a new coating technology, namely the aluminum oxide hydrolysis process. This process achieves an ultra-low reflectivity of 0.1% in the visible light band for the coated lenses, significantly reducing stray light and ghosting, and improving overall image quality. However, this process can cause fogging in real-world shots due to its scattering properties, which is particularly pronounced when multiple lenses in a single camera are coated with this process.

[0003] Therefore, it is necessary to propose a new composite film layer structure that can reduce scattering while meeting ultra-low reflectivity and solve the technical problem of fogging in actual shooting.

[0004] [Summary of the invention]

[0005] The object of the present invention is to overcome the above technical problems and provide a composite film layer structure with low reflectivity and low scattering.

[0006] In order to achieve the above-mentioned purpose, the present invention proposes a composite film layer structure, which includes a substrate, an intermediate layer coated on the substrate, a first low-reflection film layer coated on the surface of the intermediate layer away from the substrate, and a second low-reflection film layer coated on the surface of the first low-reflection film layer away from the intermediate layer, wherein the equivalent refractive index of the second low-reflection film layer is less than the equivalent refractive index of the first low-reflection film layer.

[0007] Preferably, the equivalent refractive index of the first low-reflection film layer is n1, and the equivalent refractive index of the second low-reflection film layer is n2, wherein 1.15≤n1≤1.38, and 1.05≤n2≤1.15.

[0008] Preferably, the thickness of the first low-reflection film layer and the thickness of the second low-reflection film layer are both 50-200 nm.

[0009] Preferably, the first low-reflection film layer and the second reflective film layer both include spherical silica particles with a diameter of 50-150 nm, wherein the diameter of the spherical silica particles in the first low-reflection film layer is larger than the diameter of the spherical silica particles in the second low-reflection film layer, and the porosity of the first low-reflection film layer is smaller than the porosity of the second low-reflection film layer.

[0010] Preferably, the substrate is a resin lens.

[0011] Preferably, the intermediate layer includes at least one of Ti3O5, H4, Nb2O5, HfO2, L5 silicon-aluminum mixture, SiO2, MgF2, and Al2O3.

[0012] Compared with the related art, the composite film layer structure provided by the present invention includes a substrate and an intermediate layer, a first low-reflection film layer and a second low-reflection film layer sequentially coated on the substrate, and the equivalent refractive index of the second low-reflection film layer is less than the equivalent refractive index of the first low-reflection film layer; when the incident angle is 0°, the average reflectivity of the composite film layer structure in the 380-980nm band is less than 0.1%, so that it has ultra-low reflectivity and low scattering characteristics, effectively solving the problem of fogging in actual shooting and significantly improving image quality.

Brief Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work, among which:

[0014] FIG1 is a schematic diagram of the composite membrane structure of the present invention;

[0015] FIG2 is an SEM surface morphology of the first low-reflection layer in the composite film structure of the present invention;

[0016] FIG3 is a SEM surface morphology of a membrane structure in the prior art;

[0017] FIG4 is a graph showing reflectivity data at different incident angles of a film structure in the prior art;

[0018] FIG5 is a schematic diagram of the reflectivity of the composite film structure at different incident angles in the present invention. [Specific implementation method]

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0020] As shown in Figure 1, the present invention provides a composite film layer structure 100, which includes a substrate 10, an intermediate layer 20 coated on the substrate 10, a first low-reflection film layer 30 coated on the surface of the intermediate layer 20 away from the substrate 10, and a second low-reflection film layer 40 coated on the surface of the first low-reflection film layer 30 away from the intermediate layer 20.

[0021] The thickness of the first low-reflection film layer 30 is 50-200 nm; the thickness of the second low-reflection film layer 40 is also 50-200 nm; the thicknesses of the first low-reflection film layer 30 and the second low-reflection film layer 40 can be the same or different, and can be adjusted according to actual needs.

[0022] Figure 2 shows the SEM surface morphology of the first low-reflection film layer 30. Specifically, the first low-reflection film layer 30 is made of spherical silica particles with a diameter of 50-150 nm. The second reflective film layer 40 is also made of spherical silica particles with a diameter of 50-150 nm. However, in the composite film layer structure 100 provided by the present invention, the diameter of the spherical silica particles in the first low-reflection film layer 30 is larger than the diameter of the spherical silica particles in the second low-reflection film layer 40. The spherical silica particles in the first low-reflection film layer 30 are large, and therefore have a low porosity. The spherical silica particles in the second low-reflection film layer 40 are small and have a high porosity, resulting in the porosity of the first low-reflection film layer 30 being lower than that of the second low-reflection film layer 40. The equivalent refractive index of the second low-reflection film layer 40 is lower than that of the first low-reflection film layer 30. Specifically, the equivalent refractive index of the first low-reflection film layer 30 is n1, and the equivalent refractive index of the second low-reflection film layer 40 is n2, which satisfy 1.15≤n1≤1.38 and 1.05≤n2≤1.15.

[0023] As can be seen in Figure 3, the film structure produced on the surface of conventional lenses using an aluminum oxide hydrolysis process exhibits a grass-like surface morphology, with sharp particle ends. This significantly scatters light when it reaches the film structure, causing fogging in real-life shots and affecting image quality. However, Figure 2 shows an SEM surface topography image of the first low-reflection film layer 30 of the present invention, demonstrating the relatively flat appearance of the spherical silica particles therein. This effectively addresses the light scattering issue and improves image quality.

[0024] It is understood that the substrate 10 is a resin lens, and its raw material can be selected from one of APEL, EP, OKP, SP, and K26R. The intermediate layer 20 includes at least one of Ti3O5, H4, Nb2O5, HfO2, L5 silicon-aluminum mixture, SiO2, MgF2, and Al2O3.

[0025] Furthermore, the present invention also provides reflectivity data of the composite film layer structure 100 and a conventional AR film structure when the incident angles AOI are 0°, 45°, and 60°. The specific data are shown in Table 1 below.

[0026] Table 1 Reflectivity of the composite film structure 100 of the present invention and conventional AR film structure

[0027] From Table 1, Figures 4 and 5 above, it can be seen that the reflectivity of the composite film layer structure 100 of the present invention is significantly superior to that of conventional AR film structures. When the angle of incidence AOI of light is 0°, the average reflectivity Rave of the composite film layer structure 100 in the 380-980nm band is 0.05%, and the maximum reflectivity Rmax is only 0.07%, which is lower than 0.1%. Compared with conventional AR film structures, there is a significant improvement. When the angle of incidence AOI of light is 60°, the average reflectivity Rave of the composite film layer structure 100 in the 380-980nm band is 0.97%, which is less than one-fifth of the reflectivity of conventional AR films, and has significant advantages in optical properties.

[0028] The present invention further tests the reliability of the composite membrane structure 100 , and the test conditions are shown in Table 2 below.

[0029] Table 2 Reliability test conditions

[0030] The composite film layer structure 100 provided by the present invention has no film shedding, cracking or fogging in high temperature environment, high temperature and high humidity environment, low temperature environment and hot and cold shock environment, and has good reliability, so that users can still obtain good image quality when using an optical lens with the composite film layer structure in various extreme environments.

[0031] Compared with the related art, the composite film layer structure provided by the present invention includes a substrate and an intermediate layer, a first low-reflection film layer and a second low-reflection film layer sequentially coated on the substrate, and the equivalent refractive index of the second low-reflection film layer is less than the equivalent refractive index of the first low-reflection film layer; when the incident angle is 0°, the average reflectivity of the composite film layer structure in the 380-980nm band is less than 0.1%, so that it has ultra-low reflectivity and low scattering characteristics, effectively solving the problem of fogging in actual shooting and significantly improving image quality.

[0032] The above description is only an embodiment of the present invention. It should be pointed out that those skilled in the art can make improvements without departing from the creative concept of the present invention, but these improvements all fall within the scope of protection of the present invention.

Claims

1. A composite membrane structure, characterized in that: The invention comprises a substrate, an intermediate layer coated on the substrate, a first low-reflection film layer coated on the surface of the intermediate layer away from the substrate, and a second low-reflection film layer coated on the surface of the first low-reflection film layer away from the intermediate layer, wherein the equivalent refractive index of the second low-reflection film layer is less than the equivalent refractive index of the first low-reflection film layer.

2. The composite membrane structure according to claim 1, characterized in that: The equivalent refractive index of the first low-reflection film layer is n1, and the equivalent refractive index of the second low-reflection film layer is n2, wherein 1.15≤n1≤1.38, and 1.05≤n2≤1.

15.

3. The composite membrane structure according to claim 1, characterized in that: The thickness of the first low-reflection film layer and the thickness of the second low-reflection film layer are both 50-200 nm.

4. The composite membrane structure according to claim 1, characterized in that: The first low-reflection film layer and the second reflective film layer both include spherical silica particles with a diameter of 50-150 nm, wherein the diameter of the spherical silica particles in the first low-reflection film layer is larger than the diameter of the spherical silica particles in the second low-reflection film layer, and the porosity of the first low-reflection film layer is smaller than the porosity of the second low-reflection film layer.

5. The composite membrane structure according to claim 1, characterized in that: The substrate is a resin lens.

6. The composite membrane structure according to claim 1, characterized in that: The intermediate layer includes at least one of Ti3O5, H4, Nb2O5, HfO2, L5 silicon-aluminum mixture, SiO2, MgF2, and Al2O3.

Images