KR101884893B1 - Optical multilayer structure and display device comprising the same - Google Patents

Abstract

An optical multilayer film structure is provided. The optical multilayer film structure comprises a transparent substrate disposed on the front surface of a display device; and a multilayer film laminated on the surface of the transparent substrate in a plurality of layers to increase the visible light transmittance rate and increase the infrared ray shielding rate, wherein the multi-layered film comprises a 1-1 high refractive index layer made of a Nb2O5 material and laminated with a thickness of 105 nm to 115 nm on the surface of the transparent substrate, a 2-1 low refractive index layer made of a SiO2 material and laminated with a thickness of 165 nm to 175 nm on the 1-1 high refractive index layer, a 1-2 high refractive index layer made of a Nb2O5 material and laminated with a thickness of 95 nm to 105 nm on the 1-1 low refractive layer, and a 2-2 low refractive index layer made of a SiO2 material and laminated with a thickness of 75 nm to 85 nm on the 1-1 low refractive layer.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical multilayer film structure and a display device having the optical multilayer film structure.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical multilayer structure and a display device having the same, and more particularly, The present invention relates to an optical multilayer film structure and a display device having the same.

Recently, a display device has been fabricated with an LCD (Liquid Crystal Display), an LED (Light Emitting Diodes), an OLED (Organic Light Emitting Diodes) or the like which can keep its thickness thin compared with the area of an image portion.

There is an increasing tendency to use an outdoor display device, especially an outdoor DID (Digital Information Display) device, which is installed outdoors for an advertisement or the like and displays an image.

Since the outdoor display device is disposed in a state exposed to the outside, the external light (sunlight, outdoor billboard light) is reflected on the display screen, so that the glare phenomenon occurs and the shape of the object is reflected on the display screen have. In addition, the outdoor display device is overheated by the sunlight to cause damage such as phase transition of the liquid crystal.

Accordingly, it is an object of the present invention to provide an optical multilayer structure on a transparent substrate disposed on a front surface of an outdoor display device, thereby increasing visible light transmittance, minimizing reflection of light incident on a display screen, A display device having the optical multilayer film structure, and a method of manufacturing the optical multilayer film structure.

According to an aspect of the present invention, there is provided an optical multi-

A transparent substrate disposed on a front surface of the display device; And a multilayer film laminated on the surface of the transparent substrate to increase the visible light transmittance and the infrared ray shielding ratio, wherein the multilayer film is made of Nb ₂ O ₅ and has a thickness of 105 nm to 115 nm A 1-1 high-refraction layer deposited on the surface of the substrate, a SiO ₂ And is composed of a 2-1 low refractive index layer and a Nb ₂ O ₅ material which are laminated on the 1-1 high refractive index layer with a thickness of 165 nm to 175 nm and has a thickness of 95 nm to 105 nm, A first-second high refraction layer laminated on the low refraction layer, and a second -2 low refraction layer made of a SiO ₂ material and being laminated on the first low refraction layer with a thickness of 75 nm to 85 nm .

A display device according to another aspect of the present invention is configured to include an optical multilayer film structure.

According to another aspect of the present invention, there is provided a method of manufacturing an optical multilayer structure, comprising: preparing a transparent substrate disposed on a front surface of a display device; And the method comprising: and wherein the depositing step of depositing a multi-layer film to increase the infrared shielding rate are stacked in multiple layers at the same time to increase the visible light transmission on the surface of the transparent substrate on the transparent base material, Nb ₂ O ₅ material Depositing a 1-1 high-refraction layer on the surface of the transparent substrate to a thickness of 105 nm to 115 nm; SiO ₂ Depositing a 2-1 low refraction layer made of material on the 1-1 high refraction layer to a thickness of 165-175 nm; Depositing a first 1-2 high refractive layer of Nb ₂ O ₅ material on the 2-1 low refractive layer to a thickness of 95 nm to 105 nm; And SiO ₂ And depositing a 2-2 low refractive layer of the material on the 1-2 high refractive layer to a thickness of 75 nm to 85 nm.

According to the present invention, an optical multilayer structure is disposed on a front surface of a display device to increase the visible light transmittance, thereby minimizing the reflection of visible light incident on the display screen and improving the infrared shielding rate to prevent the outdoor display device from being overheated .

1 is a cross-sectional view of an optical multilayer film structure provided in a display device according to an embodiment of the present invention.
2 is a graph showing the reflectance and the light transmittance together in the visible light region of the optical multilayer structure manufactured under the thickness condition of Table 1. [
3 is a graph showing the reflectance and the light transmittance in the infrared region of the optical multi-layered structure manufactured under the thickness condition of Table 1 together.
4 is a graph showing the reflectance and the light transmittance together in the visible light region of the optical multi-layered structure fabricated under the thickness condition of Table 2;
5 is a graph showing the reflectance and the light transmittance in the infrared region of the optical multi-layered structure manufactured under the thickness condition of Table 2 together.

Best Mode for Carrying Out the Invention Various embodiments of the present invention will be described below with reference to the accompanying drawings. The various embodiments of the present invention are capable of various changes and may have various embodiments, and specific embodiments are illustrated in the drawings and the detailed description is described with reference to the drawings. It should be understood, however, that it is not intended to limit the various embodiments of the invention to the specific embodiments, but includes all changes and / or equivalents and alternatives falling within the spirit and scope of the various embodiments of the invention. In connection with the description of the drawings, like reference numerals have been used for like elements.

1 is a cross-sectional view of an optical multilayer film structure provided in a display device according to an embodiment of the present invention.

Referring to FIG. 1, a display device according to an exemplary embodiment of the present invention may be a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), or a digital information display (DID) device.

It is preferable that such a display device is applied to an outdoor display device installed in the outdoors for advertisement or the like, in particular, an outdoor DID.

In the case of an outdoor display device, since the display device is installed on the outside exposed to the sunlight, the sunlight is reflected on the display screen to generate glare and the display panel is overheated due to the heat of the sun. The optical multilayer structure included in the display device increases the visible light transmittance to reduce the reflection of light incident on the display panel and shield the infrared rays to prevent damage to the display panel due to the sun.

To this end, the display device according to the embodiment of the present invention may be configured to include a display panel and an optical multilayer structure 100 disposed on the front surface of the display panel. Since the technical core of the present invention is not a display panel, a description thereof will be replaced with a known technology, and a display panel is not shown in Fig.

The optical multilayer structure 100 according to an embodiment of the present invention may be disposed on a front surface of a display panel (not shown), and may be spaced apart from a display panel (not shown) at a certain distance. Furthermore, it may be arranged to be integrally attached to the front surface of a display panel (not shown).

Such an optical multi-film structure 100 is configured to include a transparent substrate 10 and a multilayer film 15 stacked on the transparent substrate 10.

The material of the transparent substrate 10 may be semi-tempered glass or transparent polymer resin. The transparent polymer resin may be selected from, for example, polyethylene terephthalate (PET), acrylic, polycarbonate (PC), urethane acrylate, polyester, epoxy acrylate (Epoxy Acrylate), Brominate Acrylate, PolyVinyl Chloride (PVC), and the like.

The multi-layered film 15 has a structure in which a high refractive index layer 11 having a first refractive index and a low refractive index layer 12 having a second refractive index lower than the first refractive index are repeatedly laminated. In this embodiment, the visible light transmittance Layer film 15 laminated in a four-layer structure so as to increase the infrared shielding ratio.

Accordingly, the multilayered film 15 includes a 1-1 high refraction layer 11 stacked on the transparent substrate 10, a 2-1 low refraction layer 11 stacked on the 1-1 high refraction layer 11, 12), a 1-2 first high refractive index layer 13 stacked on the 2-1 low refractive index layer 12 and a 2-2 low refractive index layer 14 stacked on the 1-2 high refractive index layer 13, . ≪ / RTI >

In this multi-layered film structure 15, the first-first high refractive index layer 11 is directly laminated on the transparent substrate 10, and the second-second low refractive index layer 14 is formed on the outside Forming the outermost layer exposed.

In this multi-layered film 15 structure, the high refractive index layers 11 and 13 have a first refractive index of 2.0 to 2.3, and the material thereof is Ti ₃ O ₅ , ZrO ₂ , Nb ₂ O ₅ , Si ₃ N _4, Water, and the low refractive layers 12 and 14 have a second refractive index of 1.3 to 1.5, and the material thereof may be any one of SiO ₂ , MgF _2, or a combination thereof.

The thickness of each layer constituting the multilayered film 15 according to the present embodiment may be variously formed so as to increase the visible light transmittance and increase the infrared ray shielding ratio.

In the first embodiment, in the multi-layered film 15 of a four-layer structure in which the materials of the high refractive index layers 11 and 13 are Nb ₂ O ₅ and the materials of the low refractive layers 12 and 14 are SiO ₂ , Are shown in Table 1 below.

matter Thickness (nm) Optimum Thickness (nm) SiO _{2
(The outermost layer)} 75 ~ 85 80 Nb ₂ O ₅ 95 ~ 105 100 S _i O ₂ 165-175 170 Nb ₂ O _{5
(The first inner layer )} 105 ~ 115 110 Glass substrate

The thicknesses of the respective layers shown in the above Table 1 were obtained by examining samples having excellent visible light transmittance and high infrared ray shielding ratio in a plurality of multilayer film samples prepared in advance and obtaining results obtained from a plurality of multilayer film samples selected And the optimum thickness of each layer is a value obtained from a sample having the best visible light transmittance among the multiple multilayer film samples selected and having the best infrared ray shielding ratio at the same time.

The applicant of the present application found that the transmittance and the reflectance in the visible light region are not greatly changed in the sample in which the thickness of the low refraction layer of SiO ₂ is made thicker than the upper limit shown in Table 1 but the infrared ray blocking rate in the infrared region is decreased And the reflectance is decreased). As a result, it was confirmed that the thermal damage of the display to the solar heat increases.

In addition, the present applicant has found that, in a sample in which the thickness of the low refraction layer of SiO ₂ is made thinner than the lower limit shown in Table 1, the infrared ray blocking rate in the infrared region increases (transmittance decreases and reflectance increases) Although the thermal damage is reduced, the light transmittance in the visible light range decreases and the reflectance increases, which can be confirmed through a number of experiments that the user has difficulty in recognizing the display (the screen becomes darker and the recognition rate drops).

In addition, the applicant of the present invention found that, in a sample in which the thickness of the high-refraction layer of Nb ₂ O ₅ is made thicker than the upper limit shown in Table 1, the infrared ray blocking rate in the infrared region increases (transmittance decreases and reflectivity increases) The received thermal damage is reduced, but the light transmittance in the visible light region is reduced and the reflectance is increased, so that it is confirmed that the user has trouble in recognizing the display (the screen becomes darker and the recognition rate is lowered).

In addition, the applicant of the present invention found that the transmittance and the reflectance in the visible light region are not greatly changed in the sample in which the thickness of the high refractive index layer of Nb ₂ O ₅ is made thinner than the lower limit shown in Table 1, but the infrared ray blocking rate in the infrared region is reduced The transmittance is increased and the reflectance is decreased), and the thermal damage to the display is increased by the solar heat.

Table 3 below shows the characteristics of the multi-layer structure fabricated under the thickness condition shown in Table 1.

Visible light 550 nm Permeation Transmittance 92.13 L * 95.72 a * -1.34 b * 2.73 reflect reflectivity 4.93 L * 29.62 a * 0.7 b * -12.3 380 to 780 nm Transmittance 84.77 reflectivity 8.97 infrared ray 1050 nm Transmittance 35.53 reflectivity 52.59 780 to 2500 nm Transmittance 64.36 reflectivity 21.08 Heat block rate 23.9

Table 3 below shows the thickness of each layer according to the second embodiment which does not fall within the thickness range of Table 1. [

matter Thickness (nm) SiO ₂ 70 Nb ₂ O ₅ 125 SiO ₂ 185 Nb ₂ O ₅ 110 Glass substrate

In Table 3, except for the thickness (110 nm) of the first-high-refractive-index layer 11 of Nb ₂ O ₅ directly stacked on the transparent substrate 10, Of the thickness of each layer.

Nevertheless, a multilayer structure capable of achieving excellent visible ray transmittance and excellent infrared ray shielding ratio could be obtained even in the case of Table 3.

It can be seen from Tables 1 and 3 that in the multilayer film 15 having the four-layer structure in which the high refractive index layer and the low refractive index layer are repeated, the thickness of the 2-1 low refractive index layer 12 in the four- The thickness of the second-second low refractive layer 14 should be designed to be the thinnest, and the thickness of the first high refractive layer should be designed to be smaller than that of the first and second high refractive layers.

Table 4 below shows the characteristics of the optical multilayer film structure fabricated under the thickness condition of Table 3.

Visible light 550 nm Permeation Transmittance 90.5 L * 94.59 a * -2.97 b * 1.09 reflect reflectivity 5.7 L * 35.87 a * 6.91 b * -3.79 380 to 780 nm Transmittance 80.9 reflectivity 11.6 infrared ray 1050 nm Transmittance 35.27 reflectivity 52.82 780 to 2500 nm Transmittance 63.11 reflectivity 23.31 Heat block rate 30.6

optics Multilayer film  Method of Manufacturing Structure 100

In the embodiment of the present invention, an optical multilayer film 15 having a multilayer film 15 of a four-layer structure in which the materials of the high refractive layers 11 and 13 are Nb ₂ O ₅ and the materials of the low refractive layers 12 and 14 are SiO ₂ , A manufacturing method of the structure will be described.

In the method of manufacturing the optical multilayer film structure 100 according to the embodiment of the present invention, a deposition process may be used.

The low refraction layers 12 and 14 of SiO ₂ can be formed by using a single crystal Si target and a ratio of argon to oxygen of 7% (for example, 100 sccm of argon (standard cubic centimeter per minute) sccm may be deposited using plasma generated by energy such as mid-range frequency sputtering power (MF) or direct current sputtering power (DC).

The high refractive index layers 11 and 13 of Nb ₂ O _5, for example, using a Nb ₂ O ₅ targets of polycrystalline argon for in the rate of oxygen 5% (e.g., oxygen 5.3 sccm argon 100 sccm) Can be deposited using MF or DC.

The multi-layer deposition process is performed at room temperature, and the multi-layer deposition process can be performed at a temperature of 600 to 650 ° C. Through the heat treatment process, the interfacial characteristics between the multi-layered films can be improved to improve the optical characteristics in the visible region and the infrared region. Here, when the temperature is less than 600 ° C., sufficient heat energy is not supplied to the SiO ₂ and Nb ₂ O ₅ thin films, so there is no change in the optical properties due to the change of the interfacial properties. When the temperature is more than 650 ° C., Therefore, it is preferable that the annealing process proceeding after deposition of the multilayer film proceeds at a temperature of 600 to 650 degrees.

FIG. 2 is a graph showing the reflectance and the light transmittance in the visible light region of the optical multilayer structure manufactured under the thickness condition of Table 1. FIG. 3 is a graph showing the reflectance in the infrared region of the optical multi- And FIG. 4 is a graph showing the reflectance and the light transmittance of the optical multilayer structure manufactured under the thickness condition of Table 2 together in the visible light region together. 5 is a graph showing the reflectance and the light transmittance in the infrared region of the optical multi-layered film structure manufactured under the thickness condition of Table 2 together.

As can be seen from FIGS. 2 to 5, it can be seen that the visible light transmittance and the infrared shielding ratio can be improved in the optical multi-layer structure fabricated according to the thickness conditions of Tables 1 and 2.

Thus, when the optical multilayer film structure of the present invention is disposed on the front surface of the outdoor display device, the visible light transmittance is increased to minimize the reflection of the light incident on the display screen and improve the infrared ray shielding rate, It is possible to prevent overheating.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications not illustrated in the drawings are possible. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (7)

delete delete delete The display device is disposed on the front surface of the transparent substrate disposed on the front surface of the outdoor display device to increase the visible light transmittance and minimize the reflection of light incident on the display screen and improve the infrared shielding ratio in the 780 to 2500 nm band, In a method of manufacturing an optical multilayer film structure that prevents components from being overheated,
Preparing a transparent substrate disposed on a front surface of the outdoor display device; And
And depositing a multilayer film on the transparent substrate, the multilayer film being laminated on the surface of the transparent substrate in a plurality of layers to increase the visible light transmittance and increase the infrared shielding ratio,
The deposition may include depositing a multilayer film having a four-layer structure according to a deposition process proceeding at room temperature,
Depositing a first-high-refractive-index layer of Nb ₂ O ₅ material on the surface of the transparent substrate with a thickness of 105 nm to 115 nm;
Depositing a 2-1 low refractive index layer of SiO ₂ material on the 1-1 high refractive index layer to a thickness of 165 nm to 175 nm;
Depositing a first-second high-refraction layer of Nb ₂ O ₅ material on the second-1 low refractive layer to a thickness of 95 nm to 105 nm; And
And depositing a _{second-second} low refractive index layer of SiO ₂ material on the first- _second high refractive index layer to a thickness of 75 nm to 85 nm,
Further comprising the step of performing a heat treatment process at a temperature of 600-650 degrees after the step of depositing the second -2 low refractive index layer.
delete The method of claim 4, wherein each of depositing the first high-refractive-index layer and the first high-
Wherein the deposition is performed using a plasma generated by MF (Mid-range Frequency Sputtering power) at 100 sccm of argon and 5.3 sccm of oxygen using a polycrystalline Nb ₂ O ₅ target.
The method of claim 4, wherein each of the steps of depositing the 2-1 low refractive layer and the 2-2 low refractive layer comprises:
Wherein the deposition is performed using a plasma generated with MF (Mid-range Frequency Sputtering power) at 100 sccm of argon and 5.3 sccm of oxygen using a single crystal Si target.

Images