KR100779943B1 - Organic Light Emitting Diode - Google Patents

Abstract

The present invention relates to an organic light emitting device that can more clearly display a picture or a character of a round outline including a curve. The organic light emitting device according to the present invention has a plurality of first electrodes arranged in one direction on a transparent substrate, and a plurality of first electrodes formed in a honeycomb form in which a plurality of hexagons are collected on the transparent substrate and the plurality of first electrodes. An insulating film defining a hexagonal pixel on the organic layer, an organic thin film layer and a second electrode sequentially formed on the first electrode of the hexagonal pixel, and a second electrode between the adjacent hexagonal pixels to prevent a short circuit It includes a partition wall formed in a portion of the insulating film along the shape.

Organic light-emitting device, hexagon, honeycomb form, pixel

Description

Organic Light Emitting Diode

1 is a plan view schematically showing the structure of an organic light emitting diode according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1 and schematically illustrates a structure of an organic light emitting diode according to an exemplary embodiment.

   -Explanation of symbols for the main parts of the drawings-

100: transparent substrate 110: first electrode

120: insulating film 130: organic thin film layer

140: second electrode 150: partition wall

The present invention relates to an organic light emitting device that can more clearly display a picture or a character of a round outline including a curve.

In general, the organic light emitting device is one of the flat panel display devices, and is formed between the positive electrode layer and the negative electrode layer on the transparent substrate via an organic thin film layer including an organic light emitting layer, and forms a very thin matrix.

Such an organic light emitting device can be driven at a low voltage of 15V or less, and exhibits excellent characteristics in brightness, viewing angle, power consumption, and the like, compared to other display devices, for example, TFT-LCD. In addition, the organic light emitting device has a fast response speed of 1 kHz compared to other display devices, and thus is suitable for a next-generation multimedia display, in which video is essential.

Typically, in such an organic light emitting device, a plurality of positive electrode layers arranged in a stripe shape is formed on a transparent substrate, and a plurality of negative electrode layers arranged in a stripe shape orthogonal to the positive electrode layer are formed on the positive electrode layer. As described above, each pixel of the organic light emitting diode having a rectangular shape is defined at a portion where a plurality of orthogonal positive electrode layers and negative electrode layers meet each other. An organic thin film layer including an organic light emitting layer and the like is formed between the positive electrode layer and the negative electrode layer of each pixel.

In a conventional organic light emitting device having such a structure, when a predetermined electric field is applied to each of the plurality of positive electrode layers and the negative electrode layers, holes and electrons are transferred from the positive electrode layer and the negative electrode layer to the organic light emitting layer of the organic thin film layer, respectively. . These holes and electrons meet with each other in the organic light emitting layer to form an electron-hole pair and generate high energy excitons. By each pixel of the rectangular shape generates light.

However, in the conventional organic light emitting device, since each pixel is formed in a rectangular shape, it is advantageous to display a letter or picture of a rectangular outline including a straight line and a right angle by combining each pixel, but a round type including a curve It is disadvantageous for displaying the letters or pictures of the outline.

In particular, the organic light-emitting device including the pixel of the prior art according to the prior art, when displaying a round contour letter or picture, including a curve, the curved portion can only be displayed as a combination of each rectangular pixel Since there is no, a problem occurs that the letters or pictures of the round outline are not clearly displayed.

Due to the problems of the prior art, there has been a continuous demand for the development of a novel organic light emitting device capable of clearly displaying pictures or letters of round contours including curves.

Accordingly, the present invention is to provide an organic light emitting device capable of clearly displaying a picture or letters of a round outline including a curve to solve the problems of the prior art as described above.

In order to achieve the above object, the present invention is a plurality of first electrodes arranged in one direction on the transparent substrate, a plurality of hexagons are formed on the transparent substrate and the plurality of first electrodes are formed in a honeycomb form of the plurality of An insulating film defining a hexagonal pixel on the first electrode, an organic thin film layer and a second electrode sequentially formed on the first electrode of the hexagonal pixel, and the second electrode between the hexagonal pixel adjacent to each other; An organic light emitting device includes a partition wall formed in a portion of the insulating layer along the hexagonal shape to prevent a short circuit.

In the organic light emitting device according to the present invention, since each pixel is formed in a hexagonal shape, the combination of the hexagonal pixels makes it possible to smoothly display a curve in a contour shape closer to the actual curve, and thus includes a round including a curve. Characters or pictures of the contour can be displayed more clearly.

In the organic light emitting diode according to the present invention, each of the hexagonal pixels on the plurality of first electrodes may include three subpixels for displaying red (R), green (G), and blue (B), respectively. Here, the three subpixels may be formed in the same area or may be formed in different areas.

However, in order to form each subpixel for displaying red (R), green (G), and blue (B), an organic light emitting layer in the organic thin film layer is formed using a fluorescent or phosphorescent material capable of generating light of each color. The blue fluorescent or phosphor developed until now has a shorter lifespan than the fluorescent or phosphor that emits light of different colors, thus forming a blue subpixel with a smaller area than the red and green subpixels. The overall lifespan of the light emitting device can be extended, which is more preferable.

Hereinafter, a structure of an organic light emitting diode according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings so that a person skilled in the art may easily implement the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. In addition, the same reference numerals are attached to similar parts throughout the present specification.

1 is a plan view schematically illustrating a structure of an organic light emitting diode according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1, and according to an embodiment of the present invention. It is sectional drawing which shows the structure of an organic light emitting element schematically.

1 and 2, in an organic light emitting diode according to an embodiment of the present invention, an indium tin oxide (ITO) or indium-doped zinc oxide or IZO is formed on a transparent substrate 100 made of transparent glass, plastic, or the like. A plurality of first electrodes 110 made of a transparent conductive material such as IXO) is arranged in either direction of the transparent substrate as the positive electrode layer.

More specifically, in the organic light emitting diode according to the present exemplary embodiment, each pixel having a hexagon shape includes three subpixels for displaying red (R), green (G), and blue (B), respectively (these pixels The configuration of the first electrode 110 will be described in more detail below.) In the plurality of first electrodes 110, three first electrodes 110 are formed in one set, and the first first electrode 110 is For example, the second sub-electrode 110 is arranged in one direction of the transparent substrate 100 in a zigzag form along the upper side of each hexagonal pixel so as to correspond to a region where a red subpixel is to be formed. For example, it is arranged in one direction of the transparent substrate 100 across the center of each hexagonal pixel so as to correspond to the region where the green subpixel is to be formed, and the third first electrode 110 is, for example, To correspond to the area where the blue subpixel is to be formed. Along the lower side of the square-shaped pixels are arranged in one direction of the transparent substrate 100 in a zigzag form.

However, as another embodiment of the present invention, unlike the configuration of the present embodiment in which the three first electrodes 110 corresponding to the three sub-pixels in each hexagonal pixel region are arranged in a set, each hexagon One first electrode 110 corresponding to the pixel area of the shape may be arranged in the form of stripes arranged in one direction of the transparent substrate.

On the other hand, the insulating film 120 is formed on the transparent substrate 100 and the first electrode 110 in a honeycomb form of a plurality of hexagons. An opening having a hexagon shape is defined on the plurality of first electrodes 110 by the insulating layer 120, and each pixel of the organic light emitting diode is formed in the opening.

The insulating film 120 has a positive profile in cross section so that the organic thin film layer 130 and the second electrode 140 formed on the first electrode 110 can cross the insulating film 120. It is formed so as to (see FIG. 2). The insulating film 120 is made of an insulating material such as a photosensitive film according to the structure of a conventional organic light emitting device.

In the present exemplary embodiment, each pixel on the first electrode 110 is defined by the insulating layer 120 in a hexagonal shape instead of a quadrangle. Thus, a combination of the hexagonal pixels includes a curve included in a letter or a picture of a round outline. It can be expressed smoothly in the form of a contour closer to the actual curve. Therefore, the organic light emitting diode according to the present embodiment can more clearly display a letter or a picture of a round outline including a curve.

On the other hand, on the first electrode 110 of the hexagonal pixel defined by the insulating film 120, an organic thin film layer 130 including an organic light emitting layer and the like and a second electrode 140 as a negative electrode layer are sequentially formed. .

As shown in FIG. 1, the organic thin film layer 130 and the second electrode 140 ride on the insulating film 120 having a positive slope in a direction perpendicular to one direction in which the first electrode 110 is arranged. It is formed to be connected in a zigzag (see the arrow in Fig. 1-the formation direction of the organic thin film layer and the second electrode).

In addition to the organic light emitting layer, the organic thin film layer 130 may further include a hole injection layer and a hole transport layer that assist hole transfer from the first electrode 110 to the organic light emitting layer, and electrons that assist electron transfer from the second electrode to the organic light emitting layer. It may further include an organic thin film such as an injection layer and an electron transport layer. Such a hole injection layer, a hole transport layer, an electron injection layer and an electron transport layer can be formed using all materials conventionally used according to the conventional configuration of the organic light emitting device that will be apparent to those skilled in the art.

In addition, the organic light emitting layer of the organic thin film layer 130 may be a low molecular fluorescent or phosphorescent material such as Alq ₃ or Anthrancene Ir (ppy) ₃ , or a polymer light emitting material such as p-phenylenevinylene (PPV), polythiophene (PT), or derivatives thereof. It can be formed using, and can be formed using all of the organic fluorescent or phosphorescent materials that have been conventionally used in the organic light emitting layer.

In the present embodiment, the organic light emitting layer is formed in three parts by using fluorescent or phosphorescent materials emitting red (R), green (G), and blue (B), in which case the light of each color is Three subpixels in the hexagonal pixel are defined by three organic light emitting layers.

That is, on the first first electrode 110 zigzag arranged along the upper side of each hexagonal pixel among the three first electrodes 110 constituting a set in each hexagonal pixel area, for example, By forming an organic light emitting layer that emits red light, a red subpixel may be defined, and for example, an organic light emitting layer that emits green light may be formed on the second first electrode 110 arranged across the center of each hexagonal pixel. By being formed, a green subpixel can be defined, and blue is formed by forming an organic light emitting layer emitting blue light, for example, on the third first electrode 110 arranged in a zigzag form along the bottom side of each hexagonal pixel. Subpixels can be defined.

However, as another embodiment of the present invention, when one first electrode 110 having a stripe shape corresponding to each hexagonal pixel region is formed, one first electrode 110 of each hexagonal pixel region is formed. Each sub-pixel is formed on the organic light emitting layer to emit light of red, green, and blue, and three sub-pixels emitting light of each color of red, green, and blue may be defined.

Each of these subpixels may be formed in the same area or may be formed in different areas. The blue fluorescent or phosphors developed to date may be applied to different fluorescent or phosphors emitting different colors, that is, red or green light. Since it has a short lifespan, by forming the blue subpixels with areas smaller than the red and green subpixels, the overall lifespan of the organic light emitting device according to the present embodiment can be extended, which is more preferable.

In addition, the second electrode 140 is a negative electrode layer of the organic light emitting device according to the configuration of a conventional organic light emitting device that is apparent to those skilled in the art, a low resistance metal material having good electrical conductivity, for example, Al, Li / Al, Mg / Ag or Ca can be used to form.

On the other hand, on the insulating film 120 of a predetermined region defining a hexagonal pixel on the first electrode 110, a partition wall 150 for preventing a short circuit between the second electrodes 140 formed in the pixels adjacent to each other is formed. It is. As shown in FIG. 1, the partition wall 150 is formed on a portion of the insulating layer 120 along the hexagonal shape of the pixel such that the first electrode 110 is connected in a direction perpendicular to the direction in which the first electrode 110 is arranged. .

In addition, as shown in FIG. 2, the partition wall 150 is formed in an overhang structure having a negative profile in cross section. According to the shadow effect caused by the barrier rib of the overlying structure, the second electrodes 140 formed on the pixels adjacent to each other along the direction in which the first electrodes 110 are arranged cannot be connected or shorted to each other.

The partition wall 150 may be formed of an insulating material, such as a photosensitive film, similarly to the insulating film 120 according to the structure of a conventional organic light emitting device that is apparent to those skilled in the art.

According to the structure of the organic light emitting device according to the present embodiment, the holes move from the first electrode 110 to the organic light emitting layer with the aid of the hole injection layer and the hole transport layer in the organic thin film layer 130, and the electron injection layer and the electron transport layer The electrons move to the organic emission layer from the second electrode 140 with the assistance. These electrons meet with each other in the organic light emitting layer to form an electron-hole pair and generate excitons having high energy. The excitons fall to a low energy ground state and the energy of the organic light emitting device Each pixel generates light.

However, in the present exemplary embodiment, since each pixel has a hexagonal shape instead of a rectangular shape, the combination of the hexagonal pixels makes it possible to smoothly display a curve closer to the actual curve. Therefore, according to the present embodiment, it is possible to more clearly display round letters or pictures including curves.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the present invention, since the rounded letters or pictures including curves can be displayed more clearly, the organic light emitting diode and various display devices using the same can be greatly improved.

Claims (5)

A plurality of first electrodes arranged in one direction on the transparent substrate, An insulating film formed on the transparent substrate and the plurality of first electrodes in a honeycomb form in which a plurality of hexagons are collected to define a hexagonal pixel on the plurality of first electrodes; An organic thin film layer and a second electrode sequentially formed on the first electrode of the hexagonal pixel; And a barrier rib formed in a portion of the insulating film along the hexagonal shape to prevent a short circuit of the second electrode between the hexagonal pixels adjacent to each other. The method of claim 1, wherein the plurality of first electrodes is a set of three first electrodes, Among these, the first first electrode is arranged in one direction of the transparent substrate in a zigzag form along the upper side of each hexagonal pixel, A second first electrode is arranged in one direction of the transparent substrate across the center of each hexagonal pixel, An organic light emitting device in which the third first electrode is arranged in one direction of the transparent substrate in a zigzag form along the lower side of each hexagonal pixel. The organic light emitting device of claim 1, wherein each of the plurality of first electrodes includes one first electrode corresponding to each hexagonal pixel area arranged in a stripe line in one direction of the transparent substrate. The organic light emitting diode of claim 1, wherein each of the hexagonal pixels includes three subpixels for displaying red (R), green (G), and blue (B), respectively. The organic light emitting device of claim 4, wherein the subpixel for displaying blue is formed with a smaller area than the subpixel for displaying the red and green.

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