阅读说明：本技术 一种全硅类材料的入射光角度低敏感性结构色薄膜 (Incident light angle low-sensitivity structural color film of all-silicon material ) 是由 陈楠 冯坤 卜轶坤 李青原 王雨思 刘晋彤 于 2021-09-22 设计创作，主要内容包括：本发明公开一种全硅类材料的入射光角度低敏感性结构色薄膜,其包括：依序层叠设置的反射增强层和吸收型减反射层,所述反射增强层与吸收型减反射层均由硅基介质材料构成。本发明提供了一种新的结构设计,创新性的使用非金属材料制备角度不敏感的光子晶体薄膜结构色器件。采用自然界广泛存在的安全环保的全硅类材料作为原材料,不仅能够降低生产成本,还可以简化生产工艺流程。相比于金属材料的高吸收,硅类介质材料在提高反射效率方面具有天然的优势。(The invention discloses an incident light angle low-sensitivity structural color film of an all-silicon material, which comprises: the reflection enhancement layer and the absorption type antireflection layer are sequentially stacked, and both the reflection enhancement layer and the absorption type antireflection layer are made of silicon-based dielectric materials. The invention provides a new structural design and innovatively uses non-metallic materials to prepare photonic crystal thin film structural color devices insensitive to angles. The all-silicon material which is widely available in the nature and is safe and environment-friendly is used as the raw material, so that the production cost can be reduced, and the production process flow can be simplified. Compared with the high absorption of metal materials, the silicon dielectric material has natural advantages in the aspect of improving the reflection efficiency.)

1. An incident light angle low sensitivity structural color thin film of an all-silicon material, comprising: the reflection enhancement layer and the absorption type antireflection layer are sequentially stacked, and both the reflection enhancement layer and the absorption type antireflection layer are made of silicon-based dielectric materials.

2. The incident light angle low sensitivity structured color film of all-silicon based material of claim 1, wherein: the reflection enhancement layer is made of silicon-based medium materials which have different refractive indexes and are alternately stacked.

3. The incident light angle low sensitivity structured color film of all-silicon based material of claim 1, wherein: the absorption type antireflection layer is formed by sequentially laminating a silicon-based dielectric material and a transparent silicon-based dielectric material which have absorption characteristics on visible light.

4. The incident light angle low sensitivity structural color thin film of the all-silicon based material according to any one of claims 1 to 3, wherein: the silicon-based dielectric material is selected from crystal Si, amorphous silicon a-Si, SiO and SiO₂、Si₃N₄、SiC、SiO_x(0<x<2) Or SiO_xN_y(x+y＝1)。

5. The incident light angle low sensitivity structured color film of all-silicon based material as claimed in claim 2, wherein: the silicon-based dielectric material is amorphous silicon a-Si and SiO₂。

6. The incident light angle low sensitivity structured color film of all-silicon based material of claim 3, wherein: the silicon substrate having absorption characteristic to visible lightThe material is SiO_x(0<x<2) The transparent silicon-like matrix dielectric material is SiO₂。

7. The incident light angle low sensitivity structured color film of all-silicon based material of claim 1, further comprising: and the substrate is arranged on the end face, far away from the absorption type antireflection layer, of the reflection enhancement layer, and at least one of highly polished glass, polished stainless steel, polished mirror aluminum or an optical plastic substrate is adopted as the substrate.

8. An incident light angle low sensitivity structural color film of all-silicon materials is characterized in that: it includes: the reflection enhancement layer and the absorption type antireflection layer are both made of silicon-based dielectric materials.

9. The application of the structural color film with low sensitivity to the incident light angle in photoelectric elements.

10. The application of the structural color film with low sensitivity to the incident light angle in coating.

Technical Field

The invention relates to a photonic crystal film made of all-dielectric materials, in particular to a photonic crystal structure color film which is insensitive to incident light angles and based on all-silicon materials.

Background

The structural color is a color generated by using an optical phenomenon such as interference, diffraction, absorption, etc. of light by using a photonic nanostructure which is fine in a material itself. Compared with the traditional pigment color, the structural color is more stable and has longer service life, so that the structural color has important application in the fields of display panels, optical detectors, decorative materials, vehicle paints, anti-counterfeiting coatings, color printing and the like in recent years.

Early conventional color filters tended to perform the filtering function using organic or chemical dyes that selectively absorbed some visible light, but this absorption-based approach tended to result in a reduction in the device reflection peak. Meanwhile, the traditional optical filter has short service life and unstable performance. To solve these problems, researchers have proposed photonic crystal-based structural color devices to replace conventional color filters. The structural color devices based on the photonic crystals are usually arranged periodically by using materials with different refractive indexes, so that the final photonic crystal film presents a specific color based on the principle of multi-beam interference. When the structure, period and thickness of the film are changed, the color of the color filter is changed. However, the change of the incident light angle causes the change of the equivalent optical length of the thin film, and the reflection spectral characteristics of the filter shift with the angle. This phenomenon of flop has caused the application of structural color devices to be very limited.

To address the problem of angular sensitivity, researchers have proposed many improvements. Such as MIM nano-disc, AAO hole, AI rectangular array structure, MIM multilayer film structure of asymmetric Fabry-Perot cavity, which can realize the structural color with low angle sensitivity, these methods usually require one or more layers of metal, such as chromium metal, silver metal, aluminum metal, gold metal, nickel metal or metal oxide such as dichloro-trioxide, magnesium fluoride, etc. or polystyrene, and at the same time, often use complicated processes such as photolithography, etching, etc.

In order to realize low sensitivity of incident light, great efforts have been made in the prior art, for example, patents such as CN105439462B use photonic crystals assembled by hollow spheres, and the incident light forms interference diffraction on the surface of the photonic crystals arranged periodically, so as to generate specific structural color with gorgeous color; however, this method requires the steps of stirring and centrifuging, chemical reaction, drying, calcining, etc., and is complicated in process steps compared with the electron beam evaporation method. For example, patents CN 105137518A, CN108919405A and other patents all use a metal + dielectric layer + metal to realize an angle-insensitive reflective color filter and introduce a preparation method thereof, which often uses glass as a substrate material to sequentially deposit a metal thin film, a dielectric thin film and a metal thin film, and the three thin films form a resonant structure to realize high reflection at a specific wavelength; however, the intrinsic absorption of metal in the visible light band inevitably causes a decrease in reflection efficiency, and it is difficult to realize high-brightness and high-saturation colors, and the use of noble metal increases the cost of mass production and manufacturing. For example, patent nos. CN108919404A and CN109752782A propose a transmissive color filter insensitive to angle, which is implemented by using a metal material + a dielectric material + a metal material, and the principle is that a specific structure is used to implement specific absorption of visible light band, so as to enable a specific band to implement high transmittance, and the transmission peak is about 40%. For example, in patents CN103744138A, CN109491002A, CN110412672B, visible light is coupled and resonated at the surface of the material by a nano circular hole array or a nano cylinder array to achieve high reflection and high absorption, so as to display a specific color; however, such methods often require reactive ion etching, wet etching, atomic layer deposition, photolithography, and the like, and the manufacturing process of such an implementation is complicated compared with the preparation of photonic crystals only by electron beam evaporation.

The photonic crystal structure color thin film which is insensitive to the angle and is realized by using the all-silicon dielectric material is not developed and researched, and the method has the advantages of low preparation cost, small process difficulty, high reflection efficiency, good tolerance to the incident angle and the like, and has important application prospects in the fields of coatings, printing ink, vehicle paint, photoelectric detection, optical display and the like.

Disclosure of Invention

The invention aims to invent a structural color film insensitive to angle based on all-silicon materials, simplify the preparation process by adopting a photonic crystal method, reduce the production cost and overcome the problem of reduced reflection efficiency caused by the absorption of metal in the common solution.

In order to solve the above technical problem, the present invention provides a structural color thin film of all-silicon material with low sensitivity to incident light angle, comprising: the reflection enhancement layer and the absorption type antireflection layer are sequentially stacked, and both the reflection enhancement layer and the absorption type antireflection layer are made of silicon-based dielectric materials.

As a possible embodiment, the reflection enhancing layer is further composed of silicon-based dielectric materials with different refractive indexes and arranged alternately on top of each other.

As a possible embodiment, further, the absorption-type antireflection layer is formed by sequentially laminating a silicon-based dielectric material having an absorption characteristic for visible light and a transparent silicon-based dielectric material.

As a possible implementation mode, further, the silicon-based dielectric material is selected from crystalline Si, amorphous silicon a-Si, SiO₂、Si₃N₄、SiC、SiO_x(0<x<2) Or SiO_xN_y(x+y＝1)。

As a possible implementation manner, further, the silicon-based dielectric material is amorphous silicon a-Si and SiO₂。

As a possible implementation manner, further, the silicon-based dielectric material having absorption characteristic to visible light is SiO_x(0<x<2) The transparent silicon-like matrix dielectric material is SiO₂。

As a possible implementation, further, it further includes: and the substrate is arranged on the end face, far away from the absorption type antireflection layer, of the reflection enhancement layer, and at least one of highly polished glass, polished stainless steel, polished mirror aluminum or an optical plastic substrate is adopted as the substrate.

An incident light angle low sensitivity structured color thin film of an all-silicon based material, comprising: the reflection enhancement layer and the absorption type antireflection layer are both made of silicon-based dielectric materials.

The application of the structural color film with low sensitivity to the incident light angle in photoelectric elements.

The application of the structural color film with low sensitivity to the incident light angle in coating.

By adopting the technical scheme, the invention has the following beneficial effects: the invention provides a new structural design and innovatively uses non-metallic materials to prepare photonic crystal thin film structural color devices insensitive to angles. The all-silicon material which is widely available in the nature and is safe and environment-friendly is used as the raw material, so that the production cost can be reduced, and the production process flow can be simplified. Compared with the high absorption of metal materials, the silicon dielectric material has natural advantages in the aspect of improving the reflection efficiency. Structurally, the mode of combining the reflection enhancement layer and the absorption type antireflection layer is selected to realize high reflection of a target waveband and low reflection of a non-target waveband, so that high purity and high saturation of final reflection color are ensured. The whole thickness of the high-refractive-index material is reasonably controlled, so that the optical path difference caused by the change of the incident light angle is reduced, the angle insensitivity of the device is greatly enhanced, the color appearance difference of the obtained structural color device in the incident light range of 0-50 degrees is small, and the device shows strong angle insensitivity. Compared with the previous research, the method provided by the invention has the advantages of environmental protection, low cost, easiness in large-scale production and the like. These advantages make the color filter with high angular insensitivity and high saturation have wide application potential in the fields of color display panels, photoelectric detectors, vehicle paints, color printing and the like.

Drawings

The invention is described in further detail below with reference to the following figures and embodiments:

FIG. 1 is a schematic structural view of the present invention in an asymmetric state;

FIG. 2 is a schematic structural view of the present invention in a symmetrical state;

FIG. 3 is a schematic diagram showing the optical constants of a common silicon-based material in the visible light band;

FIG. 4 is a graph of admittance at 420, 500, 580nm without and with an antireflection unit according to example 3 of the present invention;

FIG. 5 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 1 of the present invention;

FIG. 6 is a chromaticity coordinate diagram at an incident angle of 0 to 50 ° in example 1 of the present invention;

FIG. 7 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 2 of the present invention;

FIG. 8 is a chromaticity coordinate diagram at an incident angle of 0 to 50 ° in example 2 of the present invention;

FIG. 9 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 3 of the present invention;

FIG. 10 is a chromaticity coordinate diagram at an incident angle of 0 to 50 ° in example 3 of the present invention;

FIG. 11 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 4 of the present invention;

FIG. 12 is a chromaticity diagram at an incident angle of 0 to 50 ° in example 4 of the present invention;

FIG. 13 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 5 of the present invention;

FIG. 14 is a chromaticity coordinate diagram at an incident angle of 0 to 50 ° in example 5 of the present invention;

FIG. 15 is a graph of the reflectance spectrum at an incident angle of 0 to 50 degrees for example 6 of the present invention;

FIG. 16 is a chromaticity coordinate diagram at an incident angle of 0 to 50 ° in example 6 of the present invention;

FIG. 17 is a graph of the reflectance spectrum at an angle of incidence of 0 to 50 degrees for example 7 of the present invention;

FIG. 18 is a chromaticity diagram at an incident angle of 0 to 50 degrees in example 7 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described in detail and completely with reference to the accompanying drawings.

The invention adopts an asymmetric structure of the reflection enhancement layer and the absorption type antireflection layer and a symmetric structure of the absorption type antireflection layer, the reflection enhancement layer and the absorption type antireflection layer. The reflection enhancement unit and the absorption type antireflection unit are both made of silicon-based medium materials.

As shown in fig. 1, the present invention provides an incident light angle low-sensitivity structural color thin film of all-silicon material, which comprises: the reflection enhancement layer 1 and the absorption type antireflection layer 2 are sequentially stacked, and the reflection enhancement layer 1 and the absorption type antireflection layer 2 are both made of silicon-based dielectric materials.

Further comprising: and the substrate SUB is arranged on the end face, far away from the absorption type antireflection layer, of the reflection enhancement layer, and at least one of highly polished glass, polished stainless steel, polished mirror aluminum or an optical plastic substrate is adopted as the substrate. The substrate material of the invention adopts highly polished glass, polished stainless steel and polished mirror aluminum. As the substrate, one of optical plastic substrates such as polyethylene terephthalate (PET), cellulose Triacetate (TAC), polymethyl methacrylate (PMMA), polycarbonate/polymethyl methacrylate composite (PC/PMMA), Polyimide (PI), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl butyral (PVB), ethylene vinyl acetate copolymer (EVA), or polyurethane elastomer (TPU), Polytetrafluoroethylene (PTFE), Fluoroethylpropylene (FEP), and polyvinylidene fluoride (PVDF) may be used as the substrate, as necessary.

Further, the reflection enhancement layer 1 is made of silicon-based dielectric materials with different refractive indexes and alternately stacked with each other, and specifically includes a high refractive index silicon-based dielectric material H and a high refractive index silicon-based dielectric material L.

Furthermore, the absorption type antireflection layer is composed of a silicon-based dielectric material A and a transparent silicon-based dielectric material D which are sequentially stacked and have absorption characteristics for visible light.

Wherein the silicon-based dielectric material is selected from crystalline Si, amorphous silicon a-Si, SiO₂、Si₃N₄、SiC、SiO_x(0<x<2)、SiO_xN_y(x + y ═ 1), e.g. SiO_0.8N_0.2、SiO_0.6N_0.4、SiO_0.4N_0.6、SiO_0.2N_0.8And the silicon element is extremely rich on the earth and harmless to the human body, and compared with noble metals such as gold, silver, copper, chromium and the like used in other designs, the materials are lower in cost and simpler in preparation process. In addition, the absorption of the silicon-based material in the visible light band is relatively small, and the silicon-based material is a common choice for preparing an optical device with high reflectivity in the visible light band.

The application of the structural color film with low sensitivity to the incident light angle in photoelectric elements. For the application of the photonic crystal structure color thin film in the fields of photoelectric display, thin film optical filter, photoelectric detection, optical anti-counterfeiting thin film and the like, the asymmetric photonic crystal structure color thin film can be directly prepared by the thin film deposition processes such as Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), Sol-gel (Sol-gel) and the like, and a photoelectric thin film device is formed by the thin film and a substrate, as shown in fig. 1, the basic structure is as follows: substrate/reflection enhancing layer/absorbing anti-reflective layer/air. The reflection enhancement layer needs to use two dielectric materials with larger refractive index difference, for example, two dielectric materials with larger refractive index difference, such as amorphous silicon (a-Si) and SiO2, are selected to form a basic reflection unit.

As shown in fig. 2, a structural color thin film with low sensitivity to incident light angle of all-silicon material can also adopt a symmetric structure, which is substantially the same as an asymmetric structure, except that it includes: the solar cell comprises a release layer 1, an absorption type antireflection layer 2, a reflection enhancement layer 3 and the absorption type antireflection layer 2 which are sequentially stacked, wherein the reflection enhancement layer and the absorption type antireflection layer are both made of silicon-based dielectric materials.

The application of the structural color film with low sensitivity to the incident light angle in coating. For the fields of applying the photonic crystal structure color film to vehicle paint, anti-counterfeiting ink, industrial coating and the like, the photonic crystal structure color film can be directly prepared by film deposition processes such as Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), Sol-gel (Sol-gel) and the like, the structure is designed into a symmetrical structure in consideration of application requirements, and the positive optical crystal film is ensuredThe counter incident surface has the same color spreading effect. The film structure is deposited on the release layer, the photonic crystal structure color film is peeled from the substrate by dissolving the release layer to form color fragments which are independently composed of the photonic crystal film, and the film fragments are processed into micron-sized pigments which can be added into paint, printing ink and coating through the processes of drying, crushing and the like. As shown in fig. 2, such basic structure is: substrate/release layer/absorption type antireflection layer/reflection enhancement layer/absorption type antireflection layer/air, or structural substrate/(release layer/absorption type antireflection layer/reflection enhancement layer/absorption type antireflection layer) repeatedly prepared according to multiple color cycles considering actual process preparation conditions^PAir.

The photonic crystal film specifically uses crystal Si, amorphous silicon a-Si, SiO₂、Si₃N₄、SiC、SiO_x(0<x<2)、SiO_xN_y(x + y ═ 1) (e.g. SiO)_0.8N_0.2、SiO_0.6N_0.4、SiO_0.4N_0.6、SiO_0.2N_0.8, etc.). We show in fig. 3 the optical constants of several silicon based materials in the visible band. In order to realize high reflection of the target wave band, the reflection enhancement unit needs to adopt two dielectric materials with larger refractive index difference, such as amorphous silicon (a-Si) and SiO₂The two dielectric materials with larger refractive indexes form a basic reflecting unit. The regular 1/4 wavelength film stack structure is Sub | (HL)^PH | A, when P is relatively large, its reflectivity can be approximated as:

wherein nS is the refractive index of the substrate material, nH and nL are the refractive indexes of the high-refractive-index material and the low-refractive-index material respectively, and the film stack has 2P +1 layers in total. From equation 1, it can be seen that when the number of film stacks is fixed, the reflectivity is increased when the difference between the refractive indexes of the two materials is increased.

The reflection enhancement unit of the invention is based on the regular 1/4 wavelength film stack structure and further passes through a meterAnd (4) obtaining the result through computer optimization. The membrane system structure can adopt a symmetrical regular structure and can also be an asymmetrical non-regular structure, such as: (aHbLaH) ^ S, (bLaHbL) ^ S, (aHbL) ^ S aH, (bLaH) ^ S bL, (aHbL) ^ S cH dL, (bLaHbL) ^ S cH dL and any one or combination of a plurality of materials in the (aHbLaH) ^ S aH, (bLaHbL) ^ S cH dL and the (bLaHbL) ^ S cH dL, wherein the outermost layer of the integral film layer structure can be a high-refractive-index H layer or a low-refractive-index L layer. According to the previous single-layer preparation experiment, a-Si and SiO₂The values of the refractive indices at 650nm are 4.177, 1.463 respectively, which makes it possible to achieve a high reflectivity with a smaller number of layers. The film system structure is Sub (HL) xH, wherein Sub is K9 glass substrate, H is high refractive index material a-Si, L is low refractive index material SiO₂. When x is 2, 3 and 4, the reflection efficiency of the device is high, and the optical path accumulated by the reflection enhancement unit is small, so that the angular insensitivity of the device is ensured.

The antireflection unit performs antireflection regulation on wave bands except the target wave band, so that the final structural color device presents high color saturation. For the absorption type antireflection film, the silicon-based material A with certain absorption characteristic to visible light is mainly used as ultra-thin monocrystalline silicon Si, amorphous silicon a-Si, SiO_xAnd the transparent silicon-like base material D represents SiO₂，Si₃N₄，SiO_xN_y(x + y ═ 1) composition, and SiO was selected in the present invention_xAnd SiO₂To form an absorption type anti-reflection layer (AR unit), wherein SiO is obtained by introducing a certain amount of oxygen during the evaporation process using an amorphous silicon target_x. We can verify the effect of the absorbing anti-reflective layer using admittance plots. The admittance y is defined as the ratio of the magnetic field strength H to the electric field strength E of the material at the point, and the concept of the equivalent admittance is that whenever we superimpose a thin film on the substrate, a new admittance value can be used as the integral equivalent admittance, that is, the equivalent concept can make the substrate and the multi-layer film superimposed on the substrate equivalent to a single-layer film, and the refractive index of the equivalent single-layer film is equal to the equivalent admittance in value, so the reflectivity of the multi-layer film system is:

wherein y is₀Is the admittance (refractive index) of the incident medium and y is the equivalent admittance of the entire film structure. This equation shows that the intensity of reflection can be quantified by the distance between the admittance termination point of the device and the point of the air admittance value (1.0). Theoretically, zero reflection can be achieved when the system admittance is perfectly matched to the air admittance (i.e., the admittance ends at the air (1,0) point). When the end point of the admittance trajectory is far from the (1,0) point, the reflection corresponding to the incident wavelength is also large. Taking a red structure color device as an example, in fig. 4, light admittance diagrams of red structure colors without and with an absorbing anti-reflection layer at 420, 500 and 580nm are given, respectively. The K9 glass is used as the substrate, the initial point of the admittance track is (1.5,0), and the distance from the termination point to the air (1,0) is indicated by a black solid line. The final admittance trajectory plot coordinates for the non-absorbing antireflective layer at 500nm wavelength are (5.486, -1.311). This admittance point is quite far (1,0) from air, indicating a strong reflection. After the anti-reflection unit is added, the coordinates of the end point are (0.949, -0.087), the distance from the air is greatly reduced (1.0), and the reflection at the position is remarkably inhibited. The average reflectivity in the wavelength range of 380-600nm is calculated to be reduced from 43.58% to 1.21% after the absorption type antireflection layer is added. The absorption type anti-reflection layer can effectively suppress reflection in a short wavelength range, thereby improving purity and saturation of reflected color.

Example 1

As shown in FIG. 1, an asymmetric, diagonally insensitive silicon-based structural color device is composed of a substrate Sub, a dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO)_x) Dielectric material D (SiO)₂) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) 5-layer reflection-enhancing unit of superimposed composition (HLHLHLH), absorbing dielectric material A (SiO)_x) And dielectric material D (SiO)₂) Each layer constitutes an absorbing antireflective unit. The specific thickness of each layer thereof is given in table 1. A red structure color film insensitive to angle was prepared according to the thickness values given in Table 1. FIGS. 5 and 6 areExample 1 reflectance spectra at 0-50 ° incidence and chromaticity coordinates. The reflection peak is between 87.0% and 90.9%. The spectral drift is small, the chromaticity coordinate points are densely distributed, and good angular insensitivity is shown.

TABLE 1

Example 2

As shown in FIG. 1, an asymmetric, diagonally insensitive silicon-based structural color device is composed of a substrate Sub, a dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO)_x) Dielectric material D (SiO)_0.8N_0.2) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) 7-layer reflection-enhancing unit of superimposed composition (HLHLHLHLH), absorbing dielectric material A (SiO)_x) And dielectric material D (SiO)_0.8N_0.2) Each layer constitutes an absorbing antireflective unit. The specific thickness of each layer thereof is given by table 2. A red structure color film insensitive to angle was prepared according to the thickness values given in Table 2. FIGS. 7 and 8 are the reflectance spectrum and chromaticity coordinates at an incident angle of 0 to 50 ℃ in example 2. The reflection peak value is between 90.3% and 93.9%, the reflection efficiency is enhanced to a certain degree compared with that of the embodiment 1, meanwhile, the spectrum drift is small, the chromaticity coordinate points are densely distributed, and good angle insensitivity is shown.

TABLE 2

Example 3

As shown in FIG. 1, an asymmetric, diagonally insensitive silicon-based structural color device is composed of a substrate Sub, a dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO), dielectric material D (SiO)₂) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) 5-layer reflection-enhancing unit consisting of a stack of (HLHLHLHLH), an absorbing dielectric material A (SiO) and a dielectric material D (SiO)₂) Each layer constitutes an absorbing antireflective unit. The specific thickness of each layer thereof is given by table 3. An orange structural color film which is not sensitive to angle can be prepared according to the thickness values given in table 3. Example 3 was tested for reflectance spectra at 0-50 ° incidence. The resulting reflectance spectrum is shown in FIG. 9, and when the incident angle is changed in the range of 0-50 degrees, the reflectance spectrum has a small drift amount and a reflectance peak between 90.2% and 94.5%. Fig. 10 is a chromaticity coordinate diagram of the angle insensitive device shown in this example 4 at an incident angle of 0-50 °, and it can be seen that the device is densely distributed on the chromaticity coordinate diagram, which indicates that the device has small color appearance difference and good angle insensitivity.

TABLE 3

Example 4

As shown in FIG. 1, an asymmetric, diagonally insensitive silicon-based structural color device is composed of a substrate Sub, a dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO)_x) Dielectric material D (Si)₃N₄) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) 5-layer reflection-enhancing unit of superimposed composition (HLHLHLH), absorbing dielectric material A (SiO)_x) And a dielectric material D (Si)₃N₄) Each layer constitutes an absorbing antireflective unit. The specific thickness of each layer is given in table 4. A yellow structural film which is not sensitive to angle can be prepared according to the thickness values given in Table 4. FIGS. 11 and 12 are graphs of the reflectance spectrum and chromaticity coordinates at 0-50 incident angle of example 4. The reflection peak value is between 80.2% and 90.6%. The spectral drift is small, the chromaticity coordinate points are densely distributed, and good angular insensitivity is shown.

TABLE 4

Example 5

As shown in fig. 2, a symmetrical, angle insensitive structural color device based on silicon type material has the following basic structure: substrate/release layer/absorbing anti-reflection layer/reflection enhancement layer/absorbing anti-reflection layer/air, composed of substrate Sub, release layer (R) dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO)_x) Dielectric material D (SiO)₂) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) A symmetrical irregular reflection enhancement unit of (aHbL)2aH and an absorption medium material A (SiO)_x) And dielectric material D (SiO)₂) And an upper absorption type antireflection unit and a lower absorption type antireflection unit which are symmetrically distributed are formed. The specific thickness of each layer thereof is given in table 5. A red structure color film insensitive to angle was prepared according to the thickness values given in Table 5. FIGS. 13 and 14 are graphs of the reflectance spectrum and chromaticity coordinates at 0-50 incident angle of example 5. The reflection peak is between 83.3% and 90.8%. The spectral drift is small, the chromaticity coordinate points are densely distributed, and good angular insensitivity is shown.

TABLE 5

Example 6

As shown in fig. 2, a symmetrical, angle insensitive structural color device based on silicon type material has the following basic structure: substrate/release layer/absorbing anti-reflection layer/reflection enhancement layer/absorbing anti-reflection layer/air, composed of substrate Sub, release layer (R) dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (Si), dielectric material D (SiO)₂) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) A symmetrical irregular reflection enhancement unit which is superposed to form (aHbL) aH, an absorption medium material A single crystal (Si) and a medium material D (SiO)₂) And an upper absorption type antireflection unit and a lower absorption type antireflection unit which are symmetrically distributed are formed. Specific thickness of each layer thereofAs given by table 6. A pink structural film, which is insensitive to angle, can be prepared according to the thickness values given in Table 6. FIGS. 15 and 16 are graphs of the reflectance spectrum and chromaticity coordinates at 0-50 incident angle of example 6. The reflection peak is between 80.8% and 81.7%. The spectral drift is small, the chromaticity coordinate points are densely distributed, and good angular insensitivity is shown.

TABLE 6

Example 7

As shown in fig. 2, a symmetrical, angle insensitive structural color device based on silicon type material has the following basic structure: substrate/release layer/absorbing anti-reflection layer/reflection enhancement layer/absorbing anti-reflection layer/air, composed of substrate Sub, release layer (R) dielectric material L (SiO) on the substrate₂) Dielectric material H (a-Si), absorbing dielectric material A (SiO)_x) Dielectric material D (SiO)_0.4N_0.6) And (4) forming. Wherein the dielectric material H (a-Si) and the dielectric material L (SiO)₂) A symmetrical irregular reflection enhancing unit of (aHbL) aH, an absorption medium material A (SiO)_x) And dielectric material D (SiO)_0.4N_0.6) And an upper absorption type antireflection unit and a lower absorption type antireflection unit which are symmetrically distributed are formed. The specific thickness of each layer thereof is given in table 7. An orange structural color film which is not sensitive to angle can be prepared according to the thickness values given in table 7. FIGS. 17 and 18 are graphs of the reflectance spectrum and chromaticity coordinates at an incident angle of 0 to 50 ℃ in example 7. The reflection peak is between 77.2% and 82.5%. The spectral drift is small, the chromaticity coordinate points are densely distributed, and good angular insensitivity is shown.

TABLE 7

The foregoing is directed to embodiments of the present invention, and equivalents, modifications, substitutions and variations such as will occur to those skilled in the art, which fall within the scope and spirit of the appended claims.