KR20070105086A - Organic el display device and method for fabricating the same - Google Patents

Abstract

An organic EL display apparatus and a method for manufacturing the same are provided to prevent the reflection of the incident light by preventing the scattered reflection in the getter. An organic EL display apparatus includes an organic EL device, a transparent cap(315), a polarizing plate(316), a getter(314), and an blocking layer(310). The organic EL(Electro Luminescence) device has a first electrode, an organic light emitting layer, and a second electrode on the substrate. The transparent cap covers the organic EL device. The polarizing plate is formed on the upper part of the transparent cap. The polarizing plate polarizes the light which goes to the organic EL. The getter is formed between the organic EL device and the transparent cap. The blocking layer is formed on the surface of the transparent cap of the getter area, and prevents the light which passed through the polarizing plate from being irradiated to the getter by absorbing and reflecting it.

Description

Organic EL display device and its manufacturing method {ORGANIC EL DISPLAY DEVICE AND METHOD FOR FABRICATING THE SAME}

1 is a view showing a sealing method of an organic EL display device according to the prior art

2 is a diagram illustrating problems of the conventional top-emitting organic EL display device.

3 is a schematic diagram of an embodiment of an organic EL display device according to the present invention;

4 is a schematic view showing another embodiment of an organic EL display device according to the present invention;

<Description of Symbols for Major Parts of Drawings>

310: blocking film

311: substrate

312: protective shield

313: organic light emitting array

314: getter

315: transparent cap

316: polarizer

317: sealing agent

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the fabrication of organic electroluminescent (EL) display devices, and more particularly to encapsulation.

In general, organic EL devices are very weak in moisture and outside air. Therefore, in manufacturing an organic EL display device, an encapsulation process is performed to block the organic EL element from the outside.

1 is a diagram showing a method for sealing an organic EL according to the prior art. FIG. 1A illustrates an organic EL device having a bottom emission type, in which a pixel array is formed on a transparent substrate, and encapsulated with an opaque getter and a metal cap thereon. Such light emission is limited by the light emitting unit such as a driving device or the like. Therefore, recently, many top emission devices such as (b) of FIG. 1 are used. That is, a pixel array is formed on a substrate and encapsulated using a transparent getter and a glass cap thereon. In this case, almost the entire area of one pixel can be used as the light emitting pixel. However, in order to implement this, a transparent getter is required, but the manufacturing cost of the transparent getter is higher than that of the opaque getter, and technically, it is difficult to apply the transparent getter uniformly to one surface of the glass cap. Therefore, in order to simplify the manufacturing process and economy, a method of encapsulating an organic EL device by forming a general opaque getter near the edge of the transparent cap so as not to cover the pixel array as shown in FIG. do. In the organic EL display device as described above, the polarizing plates 112, 126, and 136 on the outer side of the light emitting part polarize light incident from the outside and prevent the polarized light from reflecting inside the device and then going out again. Therefore, even if light is emitted from the outside to the organic EL display device by the polarizing plates 112, 126, and 136, visibility can be secured by not reflecting the light from the inside.

However, the organic EL display device encapsulating the organic EL device in the same manner as in FIG. 1C has the same problem as that of FIG. 2 due to an opaque getter located at the edge of the organic cap. 2, when light is incident from the outside, the light passes through the polarizer 136 and is polarized. The polarized light prevents the light from being reflected outside by again blocking the polarization plate even when the polarized light is reflected at a part of the specular reflection such as the organic light emitting array 133. However, in the opaque getter as shown in part “A” of FIG. 2, the incident light is diffusely reflected to prevent the light from being blocked by the polarizer. That is, in the case of the organic EL element 133, the transparent protective film and the electrode material in the structure itself serve as a mirror-like reflector to reflect the polarized light, and the polarized light is again reflected to the outside by the platen plate. Block reflection However, when the opaque getter 134 is formed on the edge of the transparent cap, the surface of the getter material cannot act as a reflector such as a mirror, so that the incident light causes diffuse reflection and the polarizer does not function and input from the outside. Light is reflected back to the outside.

As a result, in the related art, the organic EL display device in which the opaque getter is formed at the edge as shown in FIG. 1C can be directly recognized by the user's eyes as the getter is formed in the module state, thereby reducing the visibility of the display device. There was this.

An object of the present invention is to increase the visibility of the organic EL display device by allowing the polarizer to have the original function even when the getter is located at the edge of the transparent cap.

In order to achieve the above object, the display device of the organic EL according to the present invention is an organic EL element formed with a first electrode, an organic light emitting layer and a second electrode on a substrate, a transparent cap covering the organic EL element, the upper side of the transparent cap Formed on the surface of the transparent cap of the polarizer plate, the getter formed between the organic EL element and the transparent cap, and the transparent cap of the getter region, and absorb or specularly reflect the light passing through the polarizer to irradiate the getter. An organic EL display device, comprising: a blocking film for blocking what is to become.

Preferably, the getter may be formed on a portion of an inner edge surrounded by the substrate and the transparent cap.

Preferably, the blocking film may be made of a metal material that specularly reflects light passing through the polarizing plate. In this case, the metal material may be composed of at least one of Al and Ni.

Preferably, the blocking film may be made of a black material that absorbs light passing through the polarizing plate. In this case, the black material may be made of Cr or Cr oxide.

Preferably, the blocking film may be formed between the getter and the transparent cap, and the blocking film may be formed between the transparent cap and the polarizing plate.

In addition, the manufacturing method of the organic EL display device according to the present invention for achieving the above object comprises the steps of preparing an organic EL device and a transparent cap having a first electrode, an organic light emitting layer and a second electrode on a substrate, the image of the transparent cap Forming a blocking film that absorbs or specularly reflects light on at least one side of the lower side, forming a getter on the transparent cap in the region where the blocking film is formed, forming a polarizing plate on an upper side of the transparent cap, and a getter and a polarizing plate And sealing the formed transparent cap and the organic EL device.

Preferably, the blocking film is formed on the upper side of the transparent cap, the getter may be formed on the transparent cap on the opposite side of the blocking film.

Preferably, the blocking film may be formed on the inner and adjacent surfaces of the groove formed on the lower side of the transparent cap, the getter may be formed on the blocking film formed inside the groove.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

EMBODIMENT OF THE INVENTION Hereinafter, the structure and operation | movement of this invention are demonstrated in detail through the Example of the organic electroluminescent display apparatus and its manufacturing method which concern on this invention.

3 shows a schematic view of an embodiment of an organic EL display device according to the present invention. Referring to FIG. 3, the organic EL display device according to the present invention includes a substrate 311, an organic emission layer 313 formed on the substrate, a protective layer 312 protecting the organic emission layer 313, and a substrate 311. A transparent cap 315 that is fixed to the top of the encapsulation 317 to cover the organic light emitting layer 313, a blocking film 310 formed on an edge of the transparent cap 315, and the blocking film 310. And a getter 314 formed below.

The organic light emitting layer 313 is composed of a first electrode, an organic material layer, and a second electrode. Since the organic material layer is very weak to moisture or air, the transparent cap 315 is formed of a substrate 311 or a protective layer 312 formed on the substrate. A sealant is fixed to a part of the phase to prevent penetration of moisture or oxidized air into the glass light emitting layer 313. When the transparent cap 315 is formed as described above, the inside of the substrate 311 and the transparent cap 315 is preferably sealed in a vacuum state. However, due to the difficulty in manufacturing, an inert gas such as nitrogen (N ₂ ) gas is The organic light emitting layer layer is sealed in the injected state. However, even in this enclosed space, water and various oxidizing air are present. Therefore, a getter 314 is formed to remove such moisture or impurities. Conventionally, as shown in (c) of FIG. 1, a groove is formed in the transparent cap to form a getter therein, but as pointed out in the conventional problem, there is a problem in that visibility is lowered due to incident and reflection of external light. In the organic EL display device according to the embodiment, as shown in FIG. 3, a groove is formed in the transparent cap to form blocking films 310 and 320 inside the groove, and a getter 314 is formed under the blocking film. It is a feature of the present invention that the polarized light passing through the polarizing plate 316 does not diffusely reflect in the getter 314 so that the polarizing plate 316 has original polarization and blocking functions. The blocking films 310 and 320 formed therein may extend out of the grooves in some cases. With the above configuration, since light incident from the outside passes through the polarizing plate 316 and is polarized and the polarized light does not diffusely diffuse in the getter, the polarizing plate does not exit the specularly reflected light to the outside, so that the outside of the inside of the getter etc. It is possible to increase the visibility and aesthetics by making the components of the invisible.

The materials constituting the blocking layers 310 and 320 may be classified into two types.

First, the blocking films 310 and 320 may be formed of a black material 310 that absorbs light passing through the polarizer 316 as shown in FIG. 3A. That is, referring to FIG. 3 (a), since the incident light is specularly reflected in portions other than the getter, the specularly reflected light is again blocked by the polarizing plate 316, and a predetermined black material is placed on the upper part of the getter. Is formed to absorb light so as not to cause diffuse reflection in the getter 314. When the barrier layer is formed of the black material 310 as described above, the getter may not be recognized by the human eye from the outside, and thus the visibility of the display device is greatly increased. The black material has a property of absorbing light, and may be made of Cr or Cr oxide.

 In addition, the blocking layers 310 and 320 may be formed of a metal material 320 that specularly reflects light passing through the polarizer 316 as shown in FIG. 3B. That is, referring to FIG. 3 (b), since the incident light is specularly reflected in portions other than the getter, the specularly reflected light is again blocked by the polarizing plate 316, and a predetermined metallic material is placed on the upper part of the getter. A 320 may be formed to block the input light with the polarizer 316 by specularly reflecting light in the same manner as parts other than the getter. If the barrier film is formed of the above materials, the getter may not be recognized by the human eye from the outside, and the visibility of the display device is greatly increased. As described above, the metal material 320 reflecting light may be made of at least one of Al and Ni.

4 is a schematic view showing still another embodiment of the organic EL display device according to the present invention. Referring to FIG. 4, the organic EL display device according to the present invention includes a substrate 331, an organic emission layer 333 formed on the substrate, a protective layer 332 protecting the organic emission layer, and a sealing agent 337 on the substrate. A glass cap 335 fixed to the organic light emitting layer 333 to cover the organic light emitting layer 333, and a getter 334 formed at the edge of the transparent cap to remove moisture and impurity air surrounded by the substrate and the transparent cap. , A polarizing plate 336 positioned on the transparent cap and blocking films 330 and 340 positioned between the transparent cap and the polarizing plate to block light incident to the getter.

When light is incident from the outside, the light is polarized in circularly polarized light while passing through the polarizer 336. Of the polarized light, the light incident on the organic light emitting layer 333 is specularly reflected like the reflective film due to the electrode layer of the light emitting layer 333, and thus the specularly reflected light does not pass through the polarizer 336, thereby blocking the incident light. do. In addition, the light incident toward the getter 334 is absorbed or reflected by the blocking films 330 and 340 formed on the transparent cap 335 on the getter 334. The reflected light is not leaked out by the polarizer. Therefore, no diffuse reflection occurs in the getter 334. As a result, since the light input from the outside does not leak out as a whole, internal components such as getters are not visible from the outside, thereby increasing visibility and aesthetics.

The materials constituting the blocking films 330 and 340 may be classified into two types.

First, the blocking films 330 and 340 may be formed of a black material 330 that absorbs light passing through the polarizer 336 as shown in FIG. 4A. That is, referring to FIG. 4 (a), since the incident light is specularly reflected in portions other than the getter, the specularly reflected light is again blocked by the polarizing plate 336 to be prevented from leaking to the outside, and is disposed on the transparent cap of the upper part of the getter. Black material is formed to absorb light so as not to cause diffuse reflection in the getter 334. When the barrier layer is formed of the black material 330 as described above, the getter may not be recognized by the human eye from the outside, and thus the visibility of the display device is greatly increased. The black material 330 has a property of absorbing light and may be made of Cr or Cr oxide.

 In addition, the blocking layers 330 and 340 may be formed of a metal material 340 that specularly reflects light passing through the polarizing plate 336 as shown in FIG. 4B. That is, referring to FIG. 4 (b), since the incident light is specularly reflected at portions other than the getter, the specularly reflected light is again blocked by the polarizing plate 336, and the predetermined light is blocked on the transparent cap of the upper part of the getter. The metal material 340 may be formed to block the input light with the polarizer 336 by specularly reflecting light in the same manner as the parts other than the getter. If the barrier film is formed of the above materials, the getter may not be recognized by the human eye from the outside, and the visibility of the display device is greatly increased. As described above, the metal material 340 reflecting light may be made of at least one of Al and Ni.

3 and 4 may be manufactured through the following manufacturing process.

First, an organic EL device having a first electrode, an organic light emitting layer, and a second electrode and a transparent cap are prepared on a substrate. A blocking film for absorbing or specularly reflecting light is formed on at least one side of upper and lower sides of the transparent cap. Here, the surface which does not couple | bond with an organic electroluminescent element among the both surfaces of a transparent cap is defined as the upper side, and the surface with a part which couple | bonds is defined as lower side. In the organic EL display device as shown in FIG. 3, the blocking films 310 and 320 are formed under the transparent cap. In particular, in the case of forming the lower side, a groove is formed in the transparent cap as much as the space in which the getter is to be formed, and a barrier film is formed in and around the periphery. In the organic EL display device as shown in FIG. 4, the blocking films 330 and 340 are formed on the transparent cap.

Then, a getter is formed on the transparent cap in the region where the blocking film is formed. The region in which the barrier film is formed is a place where light incident from the outside is blocked by the barrier film. 3, the getter is formed in contact with the blocking film formed under the transparent cap. The getter is intended to absorb moisture, so it must be exposed to the inside of the substrate and the transparent cap at a suitable depth. In addition, as shown in Figure 4 is formed on the transparent cap on the opposite side of the barrier film.

Then, a polarizing plate is formed on the transparent cap.

Then, as described above, the transparent cap on which the blocking film, the getter and the polarizing plate are formed, and the prepared organic EL device are sealed. At this time, in order to remove moisture, oxidizing air, etc. between the organic EL element and the transparent cap, encapsulate in a space filled with a stable gas such as nitrogen (N ₂ ). The sealing can be performed by applying a sealing agent to the edge and pressing. The sealing agent may be a transparent sealing agent, but otherwise, if there is a fear that diffuse reflection may occur, the above-described blocking film may be extended to the adhesive part.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

As described above, the present invention prevents diffuse reflection in the getter so that incident light is not reflected to the outside, thereby ensuring visibility of the organic EL display element and providing a high quality organic EL display device. .

Claims (11)

An organic EL device having a first electrode, an organic light emitting layer, and a second electrode formed on a substrate; A transparent cap covering the organic EL element; A polarizing plate formed on the transparent cap and polarizing light incident on the organic EL; A getter formed between the organic EL element and the transparent cap; And a blocking film formed on the transparent cap surface of the getter region and blocking the light passing through the polarizing plate from being reflected or reflected by the getter. And the getter is formed on a portion of an inner edge surrounded by the substrate and a transparent cap. The method of claim 1, wherein the barrier film An organic EL display device comprising a metal material for specularly reflecting light passing through the polarizing plate. The method of claim 3 wherein the metal material An organic EL display device comprising a material composed of at least one of Al and Ni. The method of claim 1, wherein the barrier film And an black material absorbing light passing through the polarizing plate. The method of claim 4 wherein the black material is An organic EL display device comprising Cr or Cr oxide. The method of claim 1, wherein the barrier film And an organic EL display device formed between the getter and the transparent cap. The method of claim 1, wherein the barrier film An organic EL display device, characterized in that formed between the transparent cap and the polarizing plate. Preparing an organic EL device and a transparent cap having a first electrode, an organic light emitting layer, and a second electrode on a substrate; Forming a blocking film on at least one of the upper and lower sides of the transparent cap to absorb or specularly reflect light; Forming a getter on an upper portion of the transparent cap in the region where the blocking film is formed; Forming a polarizer on an upper side of the transparent cap; And encapsulating the transparent cap and the organic EL element on which the getter and the polarizer are formed. The method of claim 9 The blocking film is formed above the transparent cap, and the getter is formed on the transparent cap opposite to the blocking film. The method of claim 9 And the barrier film is formed on the inner and adjacent surfaces of the barrier film, and the getter is formed on the barrier film formed inside the groove.

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