CN114442213A - Optical device, naked-eye 3D display device, and method for improving optical device resistance - Google Patents

Abstract

The invention provides an optical device, which comprises a grating layer, wherein the surface of the grating layer is provided with an inorganic oxide film formed by an atomic layer deposition method. According to the invention, the atomic layer deposition technology is used for plating the single-layer inorganic oxide protective layer on the lower surface of the grating layer of the traditional grating type naked eye 3D display module, or the atomic layer deposition technology is used for plating one or more groups of high-refractive index and low-refractive index alternate inorganic oxide films on the surface of the silver plating layer of the naked eye 3D display module, so that the silver plating layer on the surface of the grating layer is protected from being corroded and discolored, the resistance is increased, and the service life of the grating layer is prolonged. Inorganic oxide films deposited using atomic layer deposition techniques have superior uniformity, step coverage, conformality, and low extinction coefficient. The invention also provides a naked eye 3D display device and a method for improving the optical device performance tolerance.

Description

Optical device, naked-eye 3D display device, and method for improving optical device resistance

technical field

The invention belongs to the field of optical technology, and in particular relates to an optical device, a naked-eye 3D display device and a method for improving the resistance of the optical device.

Background technique

Most of the 3D display devices on the market now require users to wear additional 3D eyes or helmets, which has a great impact on the user's experience and comfort. Glasses-free 3D technology has gradually attracted people's attention and favor by relying on the display device itself to present 3D pictures. The current mainstream 3D display device on the market is to add a grating structure between the display module and the protective cover. The grating structure is composed of a uniquely designed grating carrier and silver or silver plated on the surface of the grating carrier by evaporation or sputtering. alloy composition. Through the uniquely designed grating structure, the incident light is reflected and adjusted, and the principle of binocular parallax is used to present a 3D effect. However, the silver coating on the surface of the grating is easily corroded and discolored in the air. The naked-eye 3D display module has poor resistance and short service life.

At present, the process route of other industries is to protect the silver coating by adding a coating layer or a sol-gel layer on the surface of the silver coating, while the surface of the naked-eye 3D grating structure is a precise micro-nano structure. The existing process route will affect the silver coating. Optical efficiency, such as reflectivity, refraction, etc., cannot be applied in the field of 3D display.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an optical device, a naked-eye 3D display device and a method for improving the resistance of the optical device. The optical device in the present invention can solve the corrosion and discoloration phenomenon of the silver coating on the surface of the traditional grating layer, and improve the performance of the optical device. Durability, thereby increasing its service life, and at the same time ensuring the luminous effect of the naked-eye 3D display module.

The invention provides an optical device comprising a grating layer, the surface of the grating layer has an inorganic oxide thin film formed by an atomic layer deposition method.

Preferably, the inorganic oxide thin film is an aluminum oxide layer, a titanium oxide layer, a hafnium oxide layer, a zirconium oxide layer or a silicon oxide layer.

Preferably, the thickness of the inorganic oxide thin film is 10-100 nm.

Preferably, the inorganic oxide thin film includes one or more groups of sub-films with a reflection enhancing film structure.

Preferably, the sub-film with the anti-reflection film structure is alternately stacked low-refractive-index film layers and high-refractive-index film layers;

The low refractive index film layer is in contact with the silver plating layer.

Preferably, the low refractive index film layer includes SiO ₂ and/or Al ₂ O ₃ ; the high refractive index film layer includes one or more of TiO ₂ , ZrO ₂ and Ti ₂ O ₅ .

Preferably, the thickness of the low refractive index film layer is the central wavelength of visible light/4; the thickness of the high refractive index film layer is the central wavelength of visible light/4.

Preferably, the naked-eye 3D display module comprises a cover layer, a grating layer, an inorganic oxide film, a liquid crystal layer and a backlight module layer that are in contact with each other in sequence;

The grating layer includes a grating carrier layer and a silver coating layer; the grating carrier layer is in contact with the cover plate layer, and the silver coating layer is in contact with the inorganic oxide thin film.

The present invention provides a naked-eye 3D display device including the optical device described above.

The present invention provides a method for improving the resistance of optical devices, comprising the following steps:

The above-mentioned inorganic oxide thin film is deposited on the surface of the grating layer by atomic layer deposition technology.

The invention provides the application of atomic layer deposition technology in naked-eye 3D display module, which adopts atomic layer deposition technology to deposit a protective layer film on the surface of a grating layer of an optical device.

Preferably, the optical device is a naked eye 3D display module.

Preferably, the protective layer film is an inorganic oxide film.

Preferably, the inorganic oxide thin film includes one or more groups of sub-films having a reflection enhancing film structure.

Preferably, the water and oxygen permeability of the inorganic oxide film is less than 5%.

The invention provides an optical device comprising a grating layer, the surface of the grating layer has an inorganic oxide thin film formed by an atomic layer deposition method. On the one hand, the invention utilizes the inorganic oxide film with good water vapor barrier properties, which can effectively block the water vapor in the air from contacting the silver coating on the surface of the grating layer, and protect the silver coating from being corroded and discolored, thereby increasing the resistance of optical devices and increasing the use of life. On the other hand, the inorganic oxide film deposited by atomic layer deposition technology has superior uniformity, step coverage and conformality, and can be uniformly deposited on the specially designed grating surface and maintain the morphology before coating. The film has a very small extinction coefficient, which ensures the luminous effect of the naked-eye 3D display module. The process of the invention is simple, only one atomic layer deposition coating process needs to be performed on the surface of the traditional grating layer, the process is simple, the process cost is low, and it has mass production.

Further, the present invention utilizes the high-folding coating layer/low-folding coating layer/silver coating layer deposited by atomic layer deposition technology to form a laminated structure, which improves the optical device's resistance to resistance, increases the service life of the optical device, and at the same time improves the luminous performance. The inorganic oxide stack deposited by atomic layer deposition technology also has excellent uniformity, step coverage and conformality, and atomic layer deposition technology can precisely control the thickness of the coating, the deposited high-fold coating / low-fold coating / silver The coating can accurately meet the design requirements of the laminated structure, which can maximize the luminous performance of the naked-eye 3D display module, and the inorganic oxide laminated film can provide better protection than a single-layer inorganic oxide. Keeping the coating thickness of each group of inorganic oxide films unchanged, the protective effect of inorganic oxides can be further increased by increasing the number of groups of high and low refractive index inorganic oxide layers. The protection effect of the inorganic oxide coating on the silver coating is better, and the loss of light is not significantly reduced.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.

1 is a schematic structural diagram of a naked-eye 3D display module in the present invention;

2 is a schematic structural diagram of a grating layer in a naked-eye 3D display module coated with a single-layer inorganic oxide film according to an embodiment of the present invention;

3 is a schematic structural diagram of a grating layer in a naked-eye 3D display module coated with a laminated inorganic oxide film according to an embodiment of the present invention;

In Figures 1-3, 1 is a cover layer, 2 is a grating layer, 201 is a grating carrier layer, 202 is a silver coating layer, 203 is a single-layer inorganic oxide film, 204 is a low refractive index inorganic oxide film, and 205 is a high Refractive index inorganic oxide film; 3 is a liquid crystal layer, 4 is a backlight module layer.

Detailed ways

The invention provides a naked-eye 3D display module, which comprises a grating layer, and the surface of the grating layer is compounded with an inorganic oxide film deposited by atomic layer.

In the present invention, the naked-eye 3D display module preferably includes a cover layer, a grating layer, a liquid crystal layer and a backlight module layer that are in contact with each other in sequence; the cover layer, the liquid crystal layer and the backlight module layer can all be adopted in the art The conventional cover layer, liquid crystal layer and backlight module layer are not particularly limited in the present invention.

In the present invention, the grating layer preferably includes a grating carrier layer, a silver plating layer and an atomic layer deposited inorganic oxide thin film layer in contact with each other in sequence.

The grating carrier layer is in contact with the liquid crystal layer, and the inorganic oxide thin film layer is in contact with the backlight module layer.

In the present invention, the silver plating layer may be a pure silver plating layer or an alloy layer containing silver.

In the present invention, the inorganic oxide thin film can be 1) a single-layer inorganic oxide thin film; or 2) an anti-reflection film structure composed of high-refractive-index film layers and low-refractive-index film layers alternately stacked in sequence .

1) The inorganic oxide film is a single-layer film

The inorganic oxide film is preferably an aluminum oxide layer, a titanium oxide layer, a hafnium oxide layer, a zirconium oxide layer or a silicon oxide layer; the thickness of the inorganic oxide film is preferably 10-100 nm, more preferably 20-50 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, preferably a range value with any of the above-mentioned numerical values as the upper or lower limit.

Scheme 1) Only a layer of 10-100nm inorganic oxide film is deposited on the surface of the silver coating to improve the resistance of the naked-eye 3D display module and increase the service life of the naked-eye 3D display module. The process is simple and the process cost is low. Etc. In order to further improve the sexual resistance and luminous performance of the naked-eye 3D display module, the present invention proposes the following scheme 2):

2) The inorganic oxide thin film layer is composed of high-refractive-index film layers and low-refractive-index film layers alternately stacked in sequence

In the aspect 2) of the present invention, the inorganic oxide thin film layer is one or more groups of sub-films of the anti-reflection film structure. In the present invention, the "multiple groups" refers to two or more groups.

In the present invention, the antireflection film structure sub-film includes alternately stacked low-refractive-index film layers and high-refractive-index film layers; the low-refractive-index film layer includes SiO ₂ and/or Al ₂ O ₃ ; The refractive index film layer includes one or more of TiO ₂ , ZrO ₂ and Ti ₂ O ₅ ; the low refractive index film layer is in contact with the silver plating layer.

In the present invention, the thickness of the low refractive index film layer is the central wavelength of visible light/4n ₁ ; the thickness of the high refractive index film layer is the central wavelength of visible light/4n ₁ ;

In the present invention, the visible light central wavelength is 550 nm; n ₁ is the refractive index of the low refractive index film layer at the visible light central wavelength; n ₂ is the high refractive index film layer's refractive index at the visible light central wavelength.

The present invention also provides a naked-eye 3D device, including the above-mentioned naked-eye 3D display module.

The present invention also provides a method for improving the resistance of optical devices, comprising the following steps:

The above-mentioned inorganic oxide thin film is deposited on the surface of the silver coating layer of the grating layer by atomic layer deposition technology.

The invention also provides the application of the atomic layer deposition technology in the optical device, which adopts the atomic layer deposition technology to deposit a protective layer film on the surface of the grating layer of the optical device.

Preferably, the optical device is a naked eye 3D display module.

Preferably, the protective layer film is an inorganic oxide film.

Preferably, the inorganic oxide thin film includes one or more groups of sub-films having a reflection enhancing film structure.

Preferably, the water and oxygen permeability of the inorganic oxide film is less than 5%.

The invention proposes a process preparation method for improving the resistance of optical devices. Atomic layer deposition technology is used to coat the surface of the grating layer with a single-layer inorganic oxide protective layer of 10-100 nm, preferably 20-50 nm, or the atomic layer deposition technology is used. One or more groups of inorganic oxide films with alternating high and low refractive indices are coated on the surface of the silver coating of the naked-eye 3D display module to protect the silver coating on the surface of the grating layer from being corroded and discolored, increasing the resistance and prolonging its service life.

Inorganic oxide films deposited using atomic layer deposition have superior uniformity, step coverage, conformality, and low extinction coefficients. In addition, atomic layer deposition technology can precisely control the thickness of the coating, and the deposited high-fold coating/low-folding coating/silver coating can accurately conform to the stacked structure. When applied to naked eye 3D, it can maximize the performance of naked eye 3D display modules. Luminous properties.

In order to further illustrate the present invention, an optical device, a naked-eye 3D display device and a method for improving the resistance of an optical device provided by the present invention will be described in detail below with reference to the embodiments, which should not be construed as limiting the protection scope of the present invention.

Comparative ratio

Gratings not treated with inorganic oxide films;

Example 1

Use atomic layer deposition technology to coat 10nm aluminum oxide film on the lower surface of the grating layer, and apply it to the naked eye 3D display module;

Example 2

Using atomic layer deposition technology to coat 20nm aluminum oxide film on the lower surface of the grating layer, and apply it to the naked eye 3D display module;

Example 3

Atomic layer deposition technology was used to coat a 50nm aluminum oxide film on the lower surface of the grating layer, and it was applied to a naked-eye 3D display module.

The naked-eye 3D display modules in Examples 1 to 3 and the comparative example were tested for performance using BM-7, and the results are shown in Table 1.

Table 1 Performance data of naked-eye 3D display modules in Examples 1 to 3 and Comparative Example

sample Comparative ratio Example 1 Example 2 Example 3 loss of brightness - 3% 3.5% 10% Color Coordinate Offset Wx - 0.73% 1.62% 4.06% Color Coordinate Offset Wy - 1.15% 2.06% 5.08% 60℃/90%RH aging for 1000h NG OK OK OK

The above three examples use the atomic layer deposition technology to coat the lower surface of the grating layer with 10nm, 20nm and 50nm thick aluminum oxide films. loss, the two color coordinates are also shifted, and the influence of the aluminum oxide film on the luminous effect increases with the increase of the coating thickness. But it can be seen that when the coating thickness is 50nm, the brightness loss and color coordinate shift values are still within the acceptable range. The aging test results show that the untreated comparative sample is unqualified after aging treatment, and the aging resistance of the lower surface of the grating layer is greatly improved after coating 10nm, 20nm and 50nm alumina films. According to the actual test results and common knowledge, it can be known that the corrosion resistance of the silver coating on the lower surface of the grating layer increases with the increase of the thickness of the aluminum oxide coating. The thickness of the aluminum oxide coating plated on the lower surface of the grating layer can be selected based on the luminous performance requirements and service life requirements of the naked-eye 3D display module.

Comparative ratio

The naked-eye 3D display module that has not been coated with inorganic oxide film is used. The refractive index n of the silver coating on the surface at the central wavelength of visible light at 550 nm is 0.125, the extinction coefficient k=3.34, and the reflectivity of the silver coating at the central wavelength of visible light R is meridional I calculated 95.975%.

Example 4

A set of aluminum oxide and titanium oxide stacks are coated on the lower surface of the grating layer using atomic layer deposition technology, and the aluminum oxide coating is in contact with the silver coating;

The refractive index _n2 of the alumina coating at the visible light center wavelength of 550nm is 1.775, and the coating thickness _d2 is 77.5nm. The surface of the alumina coating is coated with a layer of titanium oxide coating. The refractive index n1 _of the titanium oxide coating at the visible light center wavelength of 550nm is 1.913, the coating thickness d ₁ is 72nm. The high-refractive coating/low-refractive coating/silver coating forms a laminated structure, and the reflectance R' at the central wavelength of visible light is calculated by formula II to be 96.451%.

It can be seen that, after using the atomic layer deposition technology to coat a group of aluminum oxide and titanium oxide stacks on the lower surface of the grating layer, compared with the comparative example, the reflectivity of the silver coating on the surface of the grating structure at the central wavelength of visible light is increased by 0.476 %.

Example 5

A set of stacks of silicon oxide and titanium oxide are coated on the lower surface of the grating layer using atomic layer deposition technology, and the silicon oxide coating is in contact with the silver coating.

The refractive index n3 of the silicon oxide coating at the center wavelength of visible light 550nm is 1.460, and the thickness _{d3 of} the coating is 94.2nm. The surface of the silicon oxide coating is coated with a layer of titanium oxide coating. The refractive index n1 _of the titanium oxide coating at the center wavelength of visible light 550nm is 1.913, the coating thickness d ₁ is 72nm. The high-folding coating/low-folding coating/silver coating forms a laminated structure, and its reflectance R″ at the central wavelength of visible light is calculated by formula III to be 97.502%.

After using atomic layer deposition technology to coat a group of aluminum oxide and titanium oxide stacks on the lower surface of the grating layer, compared with the comparative example, the reflectivity of the silver coating on the surface of the grating structure at the central wavelength of visible light is increased by 1.527%.

The naked-eye 3D display modules in Examples 4 to 5 and the comparative example were tested for performance using BM-7, and the results are shown in Table 2.

Table 2 Performance data of naked-eye 3D display modules in Examples 3-5 and Comparative Examples

In both embodiments 4 and 5, a group of inorganic oxide thin films with alternating high and low refractive indices are plated on the surface of the grating layer, the structure of which is shown in FIG. 3 . The above examples show that only by coating a group of inorganic oxide films with alternating high and low refractive indices on the lower surface of the grating layer of the naked-eye 3D display module can increase the reflectivity of the silver coating of the naked-eye 3D display module, and improve the reflectivity of the naked-eye 3D display module. At the same time, the inorganic oxide laminated film plated on the surface of the silver coating layer of the grating layer of the naked-eye 3D display module can provide better protection effect than single-layer inorganic oxide, and can better block water vapor in the air. The silver coating on the surface of the contact grating layer protects the silver coating from being corroded, thereby increasing the resistance of the naked-eye 3D display module and prolonging the service life of the naked-eye 3D display module. Keeping the coating thickness of each group of inorganic oxide films unchanged, by increasing the number of layers of high and low refractive index inorganic oxide layers, the protection effect of inorganic oxides and the display effect of naked-eye 3D display modules can be further increased. The greater the number of groups of the compound stack, the better the protection effect of the inorganic oxide coating on the silver coating, while not significantly affecting the brightness, causing offset, etc.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (15)

1. An optical device comprising a grating layer, characterized in that the surface of the grating layer has an inorganic oxide thin film formed by an atomic layer deposition method.

2. The optical device according to claim 1, wherein the inorganic oxide thin film is an aluminum oxide layer, a titanium oxide layer, a hafnium oxide layer, a zirconium oxide layer, or a silicon oxide layer.

3. The optical device according to claim 2, wherein the inorganic oxide thin film has a thickness of 10 to 100 nm.

4. The optical device according to claim 1, wherein the inorganic oxide thin film comprises one or more sets of sub-films having an enhanced film structure.

5. The optical device according to claim 4, wherein the sub-film having the reflection-increasing film structure is a low refractive index film layer and a high refractive index film layer which are alternately laminated;

the low refractive index film layer is in contact with the silver coating.

6. The optical device of claim 5, wherein the low refractive index film layer comprises SiO₂And/or Al₂O₃(ii) a The high refractive index film layer comprises TiO₂、ZrO₂And Ti₂O₅One or more of them.

7. The optical device of claim 6, wherein the low refractive index film layer has a thickness of visible center wavelength/4 n₁(ii) a The thickness of the high-refractive-index film layer is visible light center wavelength/4 n₁；

The central wavelength of the visible light is 550 nm; n is₁The refractive index of the low-refractive-index film layer at the center wavelength of visible light; n is₂The refractive index of the high refractive index film layer at the central wavelength of visible light.

8. The optical device according to any one of claims 1 to 7, wherein the naked eye 3D display module comprises a cover plate layer, a grating layer, an inorganic oxide film, a liquid crystal layer and a backlight module layer which are sequentially contacted;

the grating layer comprises a grating carrier layer and a silver plating layer; the grating carrier layer is in contact with the cover plate layer, and the silver coating is in contact with the inorganic oxide film.

9. A naked eye 3D display device comprising the optical device according to any one of claims 1 to 8.

10. A method for improving the tolerance of an optical device, comprising the steps of:

depositing the inorganic oxide film of any one of claims 1 to 8 on the surface of the grating layer by using an atomic layer deposition technique.

11. Use of an atomic layer deposition technique in an optical device, wherein:

and depositing a protective layer film on the surface of the grating layer of the optical device by adopting an atomic layer deposition technology.

12. Use of the atomic layer deposition technique according to claim 11 in an optical device, wherein:

the optical device is a naked eye 3D display module.

13. Use of the atomic layer deposition technique according to claim 12 in an optical device, wherein the protective layer film is an inorganic oxide film.

14. Use of the atomic layer deposition technique according to claim 13 in an optical device, wherein the inorganic oxide thin film comprises one or more sets of sub-films having an enhanced film structure.

15. Use of an atomic layer deposition technique according to any of claims 13-14 in an optical device, wherein the inorganic oxide film has a water and oxygen transmission rate of less than 5%.

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