KR100685394B1 - Complementary color organic electro-luminescent device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a complementary organic electroluminescent device, comprising a cyan pixel in which one green (G) light emitting layer and a blue (B) light emitting layer are simultaneously provided in one pixel, and a blue (B) light emitting layer and red (R) in one pixel. Magenta pixel with simultaneous emission layer and yellow pixel with both red (B) emission layer and green (G) emission layer in one pixel as red (R) and green (G) pixels A color that cannot be represented by a pixel and a blue (B) pixel can be expressed.

Complementary organic electroluminescent element, pixel.

Description

Complementary color organic electroluminescent device

1 is a plan view schematically showing a pixel arrangement of an organic EL device according to the prior art.

2 is a color coordinate diagram showing a color gamut of an organic EL device according to the prior art.

3 is a plan view showing an organic EL device according to the present invention.

4 is a plan view schematically showing a pixel of an organic EL device according to the present invention;

5 is a plan view schematically illustrating a pixel arrangement of an organic EL device according to the present invention;

6 is a color coordinate diagram showing a color gamut of an organic electroluminescent device according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100: cyan pixel 200: magenta pixel

300: yellow pixel

The present invention relates to an organic electroluminescent device, and more particularly, to an organic electroluminescent device capable of reproducing complementary colors by forming two different light emitting layers on one unit pixel.

In general, the organic light emitting display device is a self-luminous display device, which has a wide viewing angle, excellent contrast, and fast response speed.

The organic light emitting diode includes a substrate, an anode disposed on the substrate, an emission layer (EML) positioned on the anode, and a cathode disposed on the emission layer. The driving principle of the organic light emitting device is as follows. When a voltage is applied between the anode and the cathode, holes are injected from the anode into the light emitting layer and electrons are injected from the cathode into the light emitting layer. The holes and electrons injected into the light emitting layer recombine in the light emitting layer to generate excitons, and the excitons emit light while transitioning from the excited state to the ground state.

In such an organic light emitting device, there is a method of forming the light emitting layers corresponding to each of the colors to realize full colors of red (R), green (G), and blue (B).

US Pat. No. 6,281,634 discloses a full color organic light emitting device in which light emitting layers corresponding to R, G, and B are formed. More specifically, the U.S. Patent discloses a full color organic electroluminescent device in which the light emitting layers are formed independently for each of the R, G, and B colors, and the other organic films except for the light emitting layers are formed in common.

The organic EL device may include a red pixel, a green pixel, and a blue pixel arranged as illustrated in FIG. 1, and may implement full color using the organic pixel.

However, when the color is reproduced using the R, G, and B pixels as described above, as shown in FIG. 2, the color within the triangular area formed by connecting the points of R, G, and B may be reproduced. Can not reproduce the color.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and by forming two different light emitting layers in one unit pixel, a complementary organic EL device capable of reproducing complementary colors of cyan light, magenta light, and yellow light The purpose is to provide.

In order to achieve the above object, the complementary organic EL device according to the present invention,

An organic light emitting device having a first electrode and a second electrode and including a light emitting layer therebetween;

2 or a plurality of thin film transistors for controlling the organic light emitting device,

A plurality of scan signal lines for supplying scan signals to the thin film transistors;

A plurality of data signal lines for supplying data to the thin film transistor, and a pixel region defined by each of the scan signal lines and the data signal lines, the pixel region including the organic light emitting element,

The pixel area includes a cyan pixel, a magenta pixel, and a yellow pixel.

The cyan pixel is provided with a green light emitting layer and a blue light emitting layer at the same time,

The magenta pixel is provided with a blue light emitting layer and a red light emitting layer at the same time,

The yellow pixel is provided with a red light emitting layer and a green light emitting layer at the same time,

The pixels are arranged in the order of cyan pixel, magenta pixel and yellow pixel;

The light emitting layer constituting the pixels is arranged in the order of green light emitting layer, blue light emitting layer, blue light emitting layer, red light emitting layer, red light emitting layer and green light emitting layer,

The light emitting layer constituting the pixels may be arranged in the order of the green light emitting layer, the blue light emitting layer, the red light emitting layer, the blue light emitting layer, the green light emitting layer, and the red light emitting layer.

Hereinafter, although not shown, a general method of manufacturing an organic light emitting display device will be described.

A transparent insulating substrate having red (R), green (G), and blue (B) unit pixel regions is provided. It is preferable to form a buffer film on the transparent insulating substrate. An active layer, a gate insulating film, a gate electrode, an interlayer insulating film, and a source / drain electrode are formed on the buffer film according to a conventional method. As a result, a pixel driving thin film transistor including an active layer, a gate electrode, and a source / drain electrode may be formed on each unit pixel region. In forming the gate electrode, data lines are formed together.

Subsequently, a passivation insulating film is formed on the substrate on which the pixel driving thin film transistor is formed, and a via hole exposing any one of source / drain electrodes of the pixel driving thin film transistor is formed in the passivation insulating film. The passivation insulating film is preferably formed of a silicon nitride film.

Subsequently, a first electrode material is stacked on the substrate on which the via hole is formed, and patterned to form a first electrode in each unit pixel region. The first electrode may be an anode or a cathode. When the first electrode is an anode, the first electrode may be formed using indium tin oxide (ITO) or indium zinc oxide (IZO), or aluminum-neodymium (AlNd) and ITO. It can be laminated | stacked and formed in order. Meanwhile, when the first electrode is a cathode, the first electrode may be formed using Mg, Ca, Al, Ag, Ba, or an alloy thereof.

Subsequently, it is preferable to form a pixel defining layer having an opening that exposes a part of the surface of the first electrode on the first electrode. The pixel defining layer having the opening serves to define a light emitting area. The pixel defining layer is preferably formed of one material selected from the group consisting of acrylic resin, BCB (benzocyclobutene) and PI (polyimide).

Next, an organic layer including at least a light emitting layer is formed on a surface of the first electrode exposed to the pixel defining layer. The organic layer may further include a hole injection layer, a hole transport layer, an electron transport layer and an electron injection layer, if necessary, the light emitting layer may be formed of a red, green and blue light emitting layer, and the following materials.

The red light emitting layer includes CBP (carbazole biphenyl) or mCP as a host material, PIQIr (acac) (bis (1-phenylisoquinoline) acetylacetonate iridium), PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium as a dopant material ), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) is formed using a phosphor containing one or more selected from the group consisting of. In addition, the red light emitting layer may be formed using a fluorescent material such as PBD: Eu (DBM) 3 (Phen) or perylene.

The green light emitting layer includes CBP or mCP as a host material and is formed using a phosphor including Ir (ppy) 3 (fac tris (2-phenylpyridine) iridium) as a dopant material. In addition, the green light emitting layer may be formed using a fluorescent material such as Alq3 (tris (8-hydroxyquinolino) aluminum).

The blue light emitting layer is a fluorescent material including one material selected from the group consisting of DPVBi, Spiro-DPVBi, Spiro-6P, distilbene (DSB), distyrylarylene (DSA), PFO-based polymer and PPV-based polymer Is formed using. When the blue light emitting layer is formed of a phosphor, optical properties are unstable and are formed using the above-described fluorescent materials.

Forming the light emitting layers for each unit pixel region may be performed by vacuum deposition using a fine metal mask or laser induced thermal imaging.

Next, a second electrode is formed. The second electrode may be an anode or a cathode. When the second electrode is an anode, the second electrode may be formed using indium tin oxide (ITO) or indium zinc oxide (IZO), or aluminum-neodymium (AlNd) and ITO. It can be laminated | stacked and formed in order. On the other hand, when the second electrode is a cathode, it can be formed using Mg, Ca, Al, Ag, Ba or alloys thereof.

3 is a plan view illustrating an organic light emitting display device according to the present invention, in which a cyan pixel in which a green light emitting layer (G) and a blue light emitting layer (B) are simultaneously provided, and a blue light emitting layer (B) and a red light emitting layer (R) are simultaneously provided. Magenta pixels are arranged in the order of yellow pixels in which the red light emitting layer R and the green light emitting layer G are simultaneously provided.

Referring to FIG. 3, a scan line 125 arranged in one direction, a data line 135 intersecting with the scan line 125 while being insulated from each other, and a cross between the scan line 125 and the data line with the scan line 125 The parallel common power line 131 is located at 135. The unit pixel is defined by the intersection of the scan line 125 and the data line 135. The scan line 125 selects a unit pixel to be driven, and the data line 135 serves to apply a data signal to the selected unit pixel.

Each unit pixel includes a switching thin film transistor 140 for switching a data signal applied to the data line 135 according to a signal applied to the scan line 125, and data input through the switching thin film transistor 140. For example, the organic light emitting diode is configured by receiving a signal based on a capacitor 145 that accumulates a charge according to a data voltage and a voltage difference applied to the common power line 131, and a charge that is accumulated in the capacitor 145. The pixel driving thin film transistor 150 which flows current to the display element 240 is positioned. The organic light emitting diode 240 includes a pixel electrode 170 and a light emitting layer electrically connected to each other through the pixel electrode 170 and the opening 175a.

4 is a plan view schematically illustrating a pixel array of an organic EL device according to the present invention, and schematically illustrates only a portion of a light emitting layer in the organic EL device of FIG. 3.

The organic electroluminescent device may include a cyan pixel 100 having a green light emitting layer G and a blue light emitting layer B at the same time, a magenta pixel 200 having a blue light emitting layer B and a red light emitting layer R at the same time; The red light emitting layer R and the green light emitting layer G are arranged in the order of the yellow pixels 300 provided at the same time. As illustrated in FIG. 5, the pixels are repeatedly arranged in the order of the cyan pixel 100, the magenta pixel 200, and the yellow pixel 300.

In addition, the light emitting layers constituting the pixels may be arranged such that light emitting layers having the same color as adjacent light emitting layers forming adjacent pixels are adjacent to each other, or light emitting layers having different colors are adjacent to each other.

For example: The cyan pixel 100 includes a green light emitting layer and a blue light emitting layer, and the magenta pixel 200 adjacent to one side of the cyan pixel 100 includes a blue light emitting layer and a red light emitting layer. Therefore, the cyan pixel 100 and the magenta pixel 200 are arranged such that the blue light emitting layers, which are the light emitting layers of the same color, are adjacent to each other. In the same manner, the yellow pixels 300 adjacent to the other side of the magenta pixel 200 are arranged such that the red light emitting layers are adjacent to each other, and the cyan pixels 100 adjacent to the other side of the yellow pixel 300 are arranged such that the green light emitting layers are adjacent to each other. .

The light emitting layer is formed using a method of depositing only necessary pixels using a fine metal mask (FMM). For example, the green light emitting layer of the yellow pixel 300 and the green light emitting layer of the cyan pixel 100 are simultaneously formed using a FMM. Can be deposited.

On the other hand, the method of driving the organic electroluminescent device is a switching thin film transistor for switching the signal applied to the data line according to the signal applied to the scan line as described above, the pixel driving in accordance with the data signal input through the switching thin film transistor It is driven by flowing current through the thin film transistor.

The pixels may be driven to implement cyan light, magenta light, or yellow light, that is, complementary colors.

Therefore, as shown in FIG. 6, all the colors in the color gamut formed by connecting the points of cyan (C), magenta (M), and yellow (Y) can be reproduced.

According to the present invention as described above, there is an advantage that can reproduce colors outside the range that can not be reproduced with red, green and blue pixels using the cyan pixel, magenta pixel and yellow pixel.

Claims (7)

An organic light emitting device having a first electrode and a second electrode and including a light emitting layer therebetween; 2 or a plurality of thin film transistors for controlling the organic light emitting device, A plurality of scan signal lines for supplying scan signals to the thin film transistors; A plurality of data signal lines for supplying data to the thin film transistor, and a plurality of unit pixel areas defined by the respective scan signal lines and the data signal lines and including the organic light emitting element, And each of the plurality of unit pixel areas includes a cyan pixel, a magenta pixel, and a yellow pixel in which two light emitting layers are arranged adjacent to each other. The method of claim 1, The cyan pixel is an organic electroluminescent device, characterized in that the green light emitting layer and the blue light emitting layer is provided at the same time. The method of claim 1, The magenta pixel is an organic electroluminescent device, characterized in that the blue light emitting layer and the red light emitting layer is provided at the same time. The method of claim 1, The yellow pixel is an organic electroluminescent device, characterized in that the red light emitting layer and the green light emitting layer is provided at the same time. The method of claim 1, The pixels are arranged in the order of cyan pixel, magenta pixel and yellow pixel. The method of claim 5, The light emitting layer of the pixels is arranged in the order of the green light emitting layer, blue light emitting layer, blue light emitting layer, red light emitting layer, red light emitting layer and green light emitting layer. The method of claim 5, The light emitting layer of the pixels is arranged in the order of green light emitting layer, blue light emitting layer, red light emitting layer, blue light emitting layer, green light emitting layer and red light emitting layer.

Images