CN216561064U - an anti-reflection film - Google Patents

Abstract

The utility model relates to an anti-reflection film, which comprises 2-6 layers of a first refractive index film, 2-6 layers of a second refractive index film and 1-2 layers of a third refractive index film; The refractive indices between adjacent film layers are different; in the order of the refractive index from high to low, the first refractive index film layer is greater than the second refractive index film layer and the refractive index of the third refractive index film layer is greater than that of the third refractive index film layer. The anti-reflection film of the utility model not only has the characteristics of low residual reflection, but also has excellent high and low temperature resistance, high temperature and high humidity resistance and ultraviolet resistance under the premise that the total number of film layers is small, which can meet the requirements of outdoor environment and The impact of ultraviolet rays on the film layer can be applied to improve the ghosting phenomenon in security lenses and car lenses.

Description

an anti-reflection film

technical field

The utility model relates to the technical field of optical films, in particular to an antireflection film.

Background technique

With the development of security monitoring and automotive field, the requirements for the imaging quality of optical lenses are getting higher and higher, and the ghost phenomenon caused by stray light has become the focus of optical lens manufacturers. The anti-reflection of a single aspherical lens is realized in the visible light and near-infrared bands, so as to reduce the intensity of ghost images and improve the image quality.

The traditional anti-reflection film is mainly made of double-layer anti-reflection film, that is, a low-refractive index film material and a high-refractive index film material are stacked, such as SiO ₂ /TiO ₂ double-layer anti-reflection film. Anti-reflection coatings often only have an anti-reflection effect on light in a narrow wavelength band, and the residual reflection is high.

CN110989053A discloses a chalcogenide glass substrate low residual reflectivity anti-reflection film and a preparation method thereof, belonging to the technical field of vacuum coating. The anti-reflection film disclosed by the anti-reflection film realizes low residual reflectivity anti-reflection with an average transmittance of 7.5 μm-10.5 μm band greater than 98% and an average residual reflectivity of less than 0.3% on a chalcogenide glass substrate by means of film system design and process optimization. Preparation of thin films. The disclosed two-sided film system is a symmetrical structure, and the basic form of the film system on both sides is: Sub/ _x1 H _x2 M _x3 H _x4 M _x5 H _x6 L _x7 M _x8 L _x9 M/Air, where H, M, L Representing the high-refractive index film, the medium-refractive-index film and the low-refractive-index film respectively, the stress of the film layers on both sides is the same, which helps to improve the surface quality and mechanical properties of the coated substrate.

CN207233746U discloses an anti-reflection film for solar cells, which includes a first film layer formed on the surface of a silicon wafer, a second film layer formed on the first film layer, and a second film layer formed on the On the third film layer, the refractive index of the first film layer is 2.15-2.4, the refractive index of the third film layer is 1.9-2.15, and the refractive index of the third film layer is smaller than the The refractive index of the first film layer and the refractive index of the second film layer gradually decrease from the side where the first film layer is located to the side where the third film layer is located. The antireflection film disclosed by the invention reduces the emission phenomenon of light at the interface layer by setting the second film layer to a graded refractive index, improves the utilization rate of incident light, and can improve the photoelectric conversion efficiency of the solar cell by more than 0.05%.

To sum up, it is very important to develop an anti-reflection film with low residual reflection, a small number of film layers, and can meet the outdoor environment and the impact of ultraviolet rays on the film layers.

Utility model content

In view of the deficiencies of the prior art, the purpose of the present invention is to provide an anti-reflection film, which has low residual reflection, a small number of film layers, and can meet the impact of outdoor environments and ultraviolet rays on the film layers, which can be applied to Improves ghosting in security footage and in-vehicle footage.

For this purpose, the utility model adopts the following technical solutions:

The utility model provides an anti-reflection film, the anti-reflection film comprises 2-6 layers (such as 3 layers, 4 layers, 5 layers, etc.) of a first refractive index film layer, 2-6 layers (such as 3 layers, 4 layers, etc.) , 5 layers, etc.) the second refractive index film layer and 1-2 layers (for example, 1 layer, 2 layers) the third refractive index film layer;

The refractive index between adjacent layers is different;

In descending order of the refractive index, the first refractive index layer is greater than the second refractive index layer and the refractive index of the third refractive index layer is greater than that of the third refractive index layer.

The anti-reflection film of the utility model sets the film layers according to the refractive index, the total number of film layers is small, and the residual reflection is low, which can meet the impact of the outdoor environment and ultraviolet rays on the film layers, and can be applied to improve security lenses and vehicle-mounted lenses. ghosting phenomenon that exists.

Preferably, the third refractive index film layer is disposed between the first refractive index film layer and the second refractive index film layer.

Preferably, the thicknesses of the first refractive index film layers are each independently 5-80 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, and the like.

Preferably, the thicknesses of the second refractive index film layers are each independently 10-45 nm, such as 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, and the like.

Preferably, the thicknesses of the third refractive index film layers are each independently 80-100 nm, such as 82 nm, 84 nm, 86 nm, 88 nm, 90 nm, 92 nm, 94 nm, 96 nm, 98 nm, and the like.

Preferably, the anti-reflection film further includes a substrate, and the first refractive index layer, the second refractive index layer and the third refractive index layer are disposed on one side of the substrate.

Preferably, the refractive index of the first refractive index film layer is 2.3-2.5, such as 2.3, 2.65, 2.4, 2.45, etc., and the refractive index of the second refractive index film layer is 1.4-1.7, such as 1.45, 1.5, 1.55, 1.6, 1.65, etc., the refractive index of the third refractive index film layer is 1.3-1.4, such as 1.32, 1.35, 1.38, etc.

Preferably, the first refractive index film layer is any one of a titanium pentoxide layer (Ti ₃ O ₅ ), a titanium oxide layer, a tantalum pentoxide layer or a niobium oxide layer.

Preferably, the second refractive index film layer is any one of a silicon dioxide layer (SiO ₂ ), a silicon monoxide layer or an aluminum oxide layer.

Preferably, the third refractive index film layer is any one of a magnesium fluoride layer (MgF ₂ ), an aluminum fluoride layer or a barium fluoride layer.

Exemplarily, the material of the first refractive index film layer is Ti ₃ O ₅ with the highest refractive index, the material of the second refractive index film layer is SiO ₂ , followed by the refractive index, and the material of the third refractive index film layer is MgF ₂ , lowest refractive index

Exemplarily, the material of the substrate is an optical plastic substrate with a grade of K26R.

Exemplarily, the preparation method of the anti-reflection film includes the following steps:

(1) Confirm the thickness, number of layers and materials of each layer of the ultra-low residual reflection anti-reflection film;

(2) Confirm the process chamber conditions that need to be controlled: the vacuum degree of the process chamber, the rotation speed of the workpiece disk, the temperature of the workpiece disk and the temperature of the side wall;

(3) Confirm the electron beam thermal evaporation conditions that need to be controlled: deposition rate, electron gun current size, oxygen flow and argon flow;

(4) Put the optical plastic substrate into the oven for baking, and use plastic film to pack it for later use after baking;

(5) loading the optical plastic substrate spared in the step (4) into the umbrella-shaped fixture, fixing it with screws and then loading it onto the workpiece tray of the vacuum coating machine;

(6) using electron beam thermal evaporation to alternately evaporate film layers under the conditions of steps (2) and (3), and the thickness of each film layer is consistent with the design parameters obtained in step (1);

Exemplarily, the electron beam thermal evaporation conditions in step (2) are: deposition rate of 0.2-0.8 nm/s, electron gun current of 50-500 mA, ion source voltage of 350-900 V, ion source current of 450-950 mA, and oxygen flow rate The size is 0-70sccm, and the argon flow size is 5-30sccm.

Exemplarily, in step (4), the baking time is 4-12 hours, and the baking temperature is 75°C-105°C.

Compared with the prior art, the utility model has the following beneficial effects:

On the premise that the total number of film layers is small, the anti-reflection film of the utility model can realize the maximum reflectivity in the 420-680nm band within 0.29%, and the maximum reflectivity in the 681-850nm band within 1.29, and has low residual reflection. It also has excellent high and low temperature resistance, high temperature and high humidity resistance and ultraviolet resistance, which can meet the impact of outdoor environment and ultraviolet rays on the film layer, and can be used to improve the ghost phenomenon in security lenses and car lenses. .

Description of drawings

1 is a schematic structural diagram of the antireflection film described in Example 1;

2 is a schematic structural diagram of the antireflection film described in Example 2;

Fig. 3 is the residual reflection spectrogram of the antireflection film described in Example 1;

4 is a residual reflection spectrogram of the antireflection film described in Example 2;

Wherein, 1-substrate; 2-second refractive index film layer; 3-first refractive index film layer; 4-third refractive index film layer.

Detailed ways

In order to facilitate the understanding of the present utility model, the present utility model enumerates the following examples. It should be understood by those skilled in the art that the embodiments are only for helping the understanding of the present invention, and should not be regarded as a specific limitation of the present invention.

Example 1

The utility model provides an anti-reflection film, the anti-reflection film comprises a substrate 1 and 3 layers of first refractive index film layers 3, 4 layers of second refractive index film layers 2 and 1 layer of third refractive index film layers arranged on one side of the substrate rate film layer 4.

The schematic diagram of its structure is shown in Figure 1. The order from bottom to top is the second refractive index film layer with a thickness of 13.9 nm, the first refractive index film layer with a thickness of 13.1 nm, the second refractive index film layer with a thickness of 26.1 nm, 44nm first refractive index film layer, 14.1nm second refractive index film layer, 28.8nm first refractive index film layer, 81.4nm third refractive index film layer and 11.5nm second refractive index film layer.

The material of the first refractive index film layer is Ti ₃ O ₅ , the highest refractive index is 2.35; the material of the second refractive index film layer is SiO ₂ , the second refractive index film layer is 1.46; the third refractive index film layer material is MgF ₂ , the refractive index is the lowest at 1.38.

The material of the substrate is an optical plastic substrate, which was purchased from Ruion under the brand name of K26R.

The preparation method of the above-mentioned anti-reflection film comprises the following steps:

(1) Confirm the thickness, number of layers and materials of each layer of the ultra-low residual reflection anti-reflection film;

(2) Confirm the conditions of the process chamber to be controlled: the vacuum degree of the process chamber is 3.5×10 ^-3 Pa, the rotation speed of the workpiece disk is 30r/min, the temperature of the workpiece disk is 90°C and the temperature of the side wall is 105°C;

(3) Confirm the electron beam thermal evaporation conditions that need to be controlled: deposition rate, electron gun current size, oxygen flow and argon flow, as follows:

The first refractive index film layer: deposition rate 0.3nm/s, electron gun current 435-450mA, ion source voltage 700V, ion source current 900mA, ion source oxygen flow 60sccm, ion source argon flow 8sccm;

Second refractive index film: deposition rate 0.6nm/s, electron gun current 165-145mA, ion source voltage 550V, ion source current 650mA, ion source oxygen flow 50sccm, ion source argon flow 8sccm;

The third refractive index film layer: deposition rate 0.6nm/s, electron gun current 45-65mA, ion source voltage 350V, ion source current 450mA, ion source oxygen flow 20sccm, ion source argon flow 20sccm;

(4) Put the optical plastic substrate into the oven for baking, and use plastic film to pack it for later use after baking;

(5) loading the optical plastic substrate spared in the step (4) into the umbrella-shaped fixture, fixing it with screws and then loading it onto the workpiece tray of the vacuum coating machine;

(6) Using electron beam thermal evaporation to alternately evaporate film layers under the conditions of steps (2) and (3), and the thickness of each film layer is consistent with the design parameters obtained in step (1).

Example 2

The utility model provides an anti-reflection film, the anti-reflection film comprises a substrate 1 and 4 first refractive index film layers 3, 5 second refractive index film layers 2 and 1 third refractive index film layer arranged on one side of the substrate rate film layer 4.

The schematic diagram of its structure is shown in Figure 2. The order from bottom to top of the substrate is a second refractive index film with a thickness of 15.3 nm, a first refractive index film with a thickness of 9.8 nm, a second refractive index film with a thickness of 32.8 nm, 25.2nm first refractive index layer, 14.6nm second refractive index layer, 78.7nm first refractive index layer, 13.1nm second refractive index layer, 24.5nm first refractive index layer, The third refractive index film layer of 89.8 nm and the second refractive index film layer of 11.1 nm.

The material of the first refractive index film layer is Ti ₃ O ₅ , the highest refractive index is 2.35; the material of the second refractive index film layer is SiO ₂ , the second refractive index film layer is 1.46; the third refractive index film layer material is MgF ₂ , the refractive index is the lowest at 1.38.

The material of the substrate is an optical plastic substrate, which was purchased from Reion under the trade name OKP4HT-L.

The preparation method of the above-mentioned antireflection film is the same as that of Example 1.

Comparative Example 1

The difference between this comparative example and Example 1 is that the third refractive index film layer is not included, and the rest are the same as Example 1.

Performance Testing

The antireflection films described in Examples 1-2 and Comparative Example 1 were tested as follows:

(1) Maximum reflectance: Obtain the reflectance spectrum in the 400nm-880nm band through the MSP-100 spectrometer, and observe the maximum reflectance of the anti-reflection film;

(2) High and low temperature resistance performance: After placing in a high and low temperature test box with a temperature of 100°C for 24 hours, place it outdoors for 4 hours to observe the shape of the anti-reflection film;

(3) High temperature and high humidity resistance: After placing in a constant temperature and humidity test box with a temperature of 70°C and a humidity of 95% for 72 hours, place it outdoors for 4 hours to observe the shape of the anti-reflection film;

(4) Ultraviolet resistance: placed in a xenon lamp weather resistance test box with a temperature of 60° C., a humidity of 85%, an illumination of 0.6W/m ² and an illumination band of 290-800 nm for 48 hours to observe the shape of the anti-reflection film.

The test results are summarized in Table 1 and Figures 3-4.

Table 1

Analysis of the data in Table 1 shows that the anti-reflection film of the present invention has a maximum reflectivity within 0.29% in the 420-680nm band, and a maximum reflectivity in the 681-850nm band of 1.29% under the premise that the total number of layers is small. It has the characteristics of low residual reflection, excellent high and low temperature resistance, high temperature and high humidity resistance and UV resistance, which can meet the impact of outdoor environment and ultraviolet rays on the film layer, and can be used to improve security lenses and car lenses. ghosting phenomenon that exists.

Analysis of FIG. 3 shows that the maximum reflectivity of Example 1 in the 420-680 nm band is 0.25%, and the maximum reflectivity in the 681-850 nm band is 1.29%.

Analysis of FIG. 4 shows that the maximum reflectivity of Example 2 in the 420-680 nm band is 0.29%, and the maximum reflectivity in the 681-850 nm band is 1.10%.

Summarizing Figures 3-4: It can be seen from the above embodiments that the anti-reflection film designed by the present invention is coated on an optical plastic substrate, and the residual reflectivity is low, and the imaging quality of the optical lens is improved.

In addition, compared with Comparative Example 1, the anti-reflection film of the present invention has a slight ghost phenomenon and high imaging quality.

The applicant declares that the present utility model illustrates the detailed method of the present utility model through the above-mentioned embodiments, but the present utility model is not limited to the above-mentioned detailed method, that is, it does not mean that the present utility model must rely on the above-mentioned detailed method to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention. within.

Claims (10)

1. An antireflection film is characterized by comprising 2-6 layers of first refractive index film layers, 2-6 layers of second refractive index film layers and 1-2 layers of third refractive index film layers;

the refractive index between adjacent film layers is different;

the refractive indexes of the first refractive index film layer and the second refractive index film layer are larger than that of the third refractive index film layer in sequence from high to low.

2. The antireflection film of claim 1 wherein the third layer of refractive index is disposed between the first and second layers of refractive index.

3. The antireflection film of claim 1 or 2 wherein the thickness of the first refractive index film layers are each independently 5 to 30 nm.

4. The antireflection film of claim 1 or 2 wherein the thickness of the second refractive index film layers are each independently 10-45 nm.

5. The antireflection film of claim 1 or 2 wherein the third refractive index film layers each independently have a thickness of 80-100 nm.

6. The antireflection film of claim 1 further comprising a substrate, wherein the first, second, and third layers of refractive index are disposed on one side of the substrate.

7. The antireflection film of claim 1 wherein the first refractive index film layer has a refractive index of from 2.3 to 2.5, the second refractive index film layer has a refractive index of from 1.4 to 1.7, and the third refractive index film layer has a refractive index of from 1.3 to 1.4.

8. The antireflection film of claim 1 wherein the first refractive index film layer is any one of a titanium pentoxide layer, a titanium sesquioxide layer, a tantalum pentoxide layer, or a niobium oxide layer.

9. The antireflection film of claim 1 wherein the second refractive index film layer is any one of a silicon dioxide layer, a silicon monoxide layer, or an aluminum oxide layer.

10. The antireflection film of claim 1 wherein the third refractive index film layer is any one of a magnesium fluoride layer, an aluminum fluoride layer, or a barium fluoride layer.

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