KR100649220B1 - Organic light emitting display - Google Patents

Abstract

An organic light emitting display device is provided to reduce a thickness and weight of the OLED(Organic Light Emitting Diode) by sealing a substrate with pixels thereon using a thin antireflection film. An organic light emitting display device includes a substrate and an antireflection film(420). Pixels having light emitting elements, where a first electrode, an organic light emitting layer, and a second electrode are sequentially laminated, are formed on the substrate. The antireflection film is formed on the substrate to cover the pixels, such that the substrate is sealed by the antireflection film. The antireflection film includes first and second layers(421,422). The first layer is made of a metal or a metal oxide material. The second layer is formed on the first layer and made of an inorganic insulation material.

Description

Organic light emitting display device {ORGANIC LIGHT EMITTING DISPLAY}

1 is a cross-sectional view illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

2 is a partial cross-sectional view illustrating a pixel of an organic light emitting diode display according to an exemplary embodiment of the present invention.

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device having a thin film encapsulation structure.

In the organic light emitting diode display, electrons and holes injected into the organic material through an anode and a cathode recombine to form an exciton, and light of a specific wavelength is generated by energy from the exciton formed. It is a self-luminous display device using the phenomenon which occurs. Accordingly, the organic light emitting diode display is attracting attention as a next-generation display device because it does not require a separate light source such as a backlight, and thus has low power consumption and easy securing of a wide viewing angle and a fast response speed compared to the liquid crystal display.

The light emitting device of the organic light emitting diode display includes a first electrode of an anode, which is a hole injection electrode, a light emitting layer, and a second electrode of a cathode, which is an electron injection electrode, and the light emitting layer is red (R), green (G; Green). ), Blue (B) is made of each organic material to achieve full color (full color). In addition, the light emitting layer has a multilayer structure including an electron transport layer (ETL) and a hole transport layer (HTL) in the emitting layer (EML) to improve the light emission efficiency by improving the balance between electrons and holes. In some cases, it may further include a separate electron injection layer (EIL) and a hole injection layer (HIL).

The OLED display is classified into a passive matrix type and an active matrix type according to a driving method.

Here, the passive driving type organic light emitting display device is simple in manufacturing process and low in manufacturing cost, but is large in power consumption and unsuitable for large area. On the other hand, since the active driving type organic light emitting display device has a thin film transistor (TFT) as a driving element, the process is more complicated and the manufacturing cost is higher than that of the passive driving type organic light emitting display device. Since the G, B independent driving method enables low power consumption, high definition, fast response speed, wide viewing angle, and thinning, the active driving organic light emitting display device is mainly applied.

On the other hand, the organic light emitting diode display has a structure in which a substrate on which the light emitting element is formed is bonded to an encapsulation substrate such as glass and sealed by a sealing member so that the light emitting element is protected from external moisture. However, in this case, the weight and thickness of the display device are increased by the encapsulation substrate, and thus, when the organic light emitting display device is applied to the portable display device, there is a problem in that it is inconvenient to carry.

The present invention is to solve the problems of the prior art as described above, an object of the present invention is to provide an organic light emitting display device that can reduce the weight and thickness by applying a sealing structure of a thin film.

In order to achieve the above object, the present invention provides a substrate on which a pixel including a light emitting element in which a first electrode, an organic light emitting layer, and a second electrode are sequentially stacked is formed, and is formed on an entire surface of the substrate to cover the pixel to encapsulate the substrate. An organic light emitting display device including an antireflection film is provided.

Here, the anti-reflection film may include an inorganic insulator having a refractive index n of about 1.4, and preferably, the anti-reflection film is formed on a first layer made of metal or metal nitride, and the refractive index n of about 1.4 is formed on the first layer. It may include a second layer made of an inorganic insulator having a).

In this case, the first layer may be made of NiCr or TiN, and the second layer may be made of silicon oxide (SiO _x ), silicon nitride (SiN _x ), or silicon oxynitride (SiO _x N _y ).

The display device may further include a planarization film formed between the pixel and the anti-reflection film and made of an organic insulating material.

In addition, the first electrode may comprise ITO / Ag / ITO, ITO / Ag alloy / ITO or AlNd / ITO, and the second electrode may comprise a transparent material such as MgAg.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a cross-sectional view of an organic light emitting diode display according to an exemplary embodiment of the present invention, and FIG. 2 is a partial cross-sectional view of a pixel of FIG. 1.

Referring to FIG. 1, in the organic light emitting diode display 100, a plurality of pixels P including the light emitting elements L are formed on the substrate 110, and the front surface of the substrate 110 is covered to cover the pixels P. Referring to FIG. The planarization film 410 and the anti-reflection film 420 are formed on the substrate 110 to encapsulate the substrate 110.

Here, the substrate 110 may be made of an insulating material such as glass or plastic or a metal material such as stainless steel (SUS).

The pixels P may be arranged in a matrix form and may further include a TFT T as a driving element. In this case, as shown in FIG. 2, the light emitting element L is formed by the planarization film 240. Insulated from and electrically connected to a portion of the TFT (T), for example, the drain electrode, through the via hole 241 provided in the planarization film 240.

The light emitting device L has a structure in which the first electrode 310, the organic light emitting layer 320, and the second electrode 340 are sequentially stacked, and the first electrode 310 is formed by the pixel defining layer 320. The OLED is electrically separated from the first electrode (not shown) of the adjacent pixel and is in contact with the organic emission layer 330 through the opening 321 provided in the pixel defining layer 320.

The first electrode 310 may be made of a material containing a high reflectance metal, for example, ITO / Ag / ITO, ITO / Ag alloy / ITO, or AlNd / ITO, and the second electrode may include a transparent material such as MgAg. have.

On the other hand, the first electrode 310 may be made of a single layer of ITO, IZO or a composite layer thereof, and the second electrode 340 may be made of MgAg or Al.

The organic light emitting layer 330 is copper phthalocyanine (CuPc), N, N'-di (naphthalen-1-yl) -N, N'-dipetyl-benzidine (N, N'-Di (naphthalene-1-). It may be made of low molecular organic materials such as yl) -N, N'-diphenyl-benzidine (NPB), tris-8-hydroxyquinoline aluminum (Alq3), or polymer organic materials.

For example, when the organic light emitting layer 330 is made of a low molecular organic material, a hole injection layer (HIL), a hole transport layer (HTL), an emitting layer (EML), and an electron transport layer (Electron Transport Layer); It may be made of a multi-layer structure including ETL).

In addition, when the organic light emitting layer 330 is formed of a polymer organic material, it may be formed of a hole transport layer (HTL) and an emitting layer (EML), wherein the HTL is made of PEDOT material and the EML is poly-phenylene. Poly-Phenylenevinylene (PPV) -based or polyfluorene (Polyfluorene) may be made of a material.

Meanwhile, the planarization layer 410 may be made of an organic insulating material such as acryl or benzocyclobutene (BCB). When the antireflection layer 420 is directly formed on the pixel P, the antireflection layer 420 may be formed. ) Can be selectively applied in consideration of disconnection.

The anti-reflection film 420 is a first layer 421 of a thin film made of metal or metal nitride, for example NiCr or TiN, and an inorganic insulator formed on the first layer 421 and having a refractive index n of about 1.4. And a second layer 422 of a thin film made of silicon oxide (SiO _x ), silicon nitride (SiN _x ), or silicon oxynitride (SiO _x N _y ). At this time, the first layer 421 may have a thickness of 50 to 250 kPa, preferably 150 kPa, and the second layer 422 may have a thickness of 500 to 1500 kPa, preferably 1000 kPa.

The anti-reflection film 420 protects the pixel P from external moisture, and when the organic light emitting diode display 100 is driven in the top emission type due to a low refractive index difference between the outside air and the second layer 422. Minimize the reflection of external light. As a result, the anti-reflection film 420 may reduce glare of the organic light emitting diode display 100 and may improve visibility and luminance characteristics.

In addition, since the first layer 421 of the anti-reflection film 420 is conductive, including a metal, the auxiliary electrode with respect to the second electrode 340 of the light emitting device L when the planarization film 410 is not applied. It can also be applied.

In the present embodiment, a case in which an antireflection film encapsulation structure consisting of two layers of thin films is applied to an active driving type organic light emitting display device is described as an example. However, the encapsulation structure may be similarly applied to a passive driving type organic light emitting display device. have.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to

As described above, the organic light emitting diode display according to the present invention has a structure in which the substrate on which the pixel is formed is encapsulated by the anti-reflection film of the thin film, thereby reducing the thickness and weight of the device.

In addition, the organic light emitting diode display according to the present invention can minimize the reflection of external light by the anti-reflection film, thereby reducing glare, improving visibility and luminance characteristics, and also preventing deterioration of the light emitting layer due to external light. have.

As a result, the organic light emitting diode display according to the present invention may improve display quality.

Claims (10)

A substrate including a pixel including a light emitting device in which a first electrode, an organic light emitting layer, and a second electrode are sequentially stacked; And An anti-reflection film formed on the entire surface of the substrate to cover the pixel to encapsulate the substrate Including, The anti-reflection film, A first layer of the anti-reflection film made of metal or metal nitride, and A second layer formed on the first layer and made of an inorganic insulator An organic light emitting display device comprising a. According to claim 1, And an inorganic insulator having an index of refraction n of 1.4. delete According to claim 1, An organic light emitting display device in which the first layer is made of NiCr or TiN. According to claim 1, The organic light emitting diode display of which the first layer has a thickness of 50 to 250 kV. According to claim 1, The organic light emitting display device of which the second layer is made of silicon oxide (SiO _x ), silicon nitride (SiN _x ), or silicon oxynitride (SiO _x N _y ). According to claim 1, An organic light emitting display device having a thickness of 500 to 1500 kW. According to claim 1, And a planarization film formed between the pixel and the anti-reflection film and made of an organic insulating material. According to claim 1, And the first electrode includes ITO / Ag / ITO, ITO / Ag alloy / ITO, or AlNd / ITO, and the second electrode includes a transparent material such as MgAg. According to claim 1, And a thin film transistor in which the pixel is electrically connected to the light emitting element.

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