KR100579177B1 - Organic electro device and driving method of the same - Google Patents

Abstract

The present invention relates to an organic electroluminescent device and a method of driving the same. In the arrangement of red pixels, green pixels, and blue pixels, the same pixels as the adjacent pixels are arranged, and the pixels are driven individually or simultaneously, so that cyan, in addition to red light, green light, and blue light, By implementing (Cyan) color light, magenta color light, and yellow color light, the range of color reproduction can be increased by only changing the arrangement of pixels used in the related art.

Complementary color, cyan light, magenta light, yellow light.

Description

Organic electroluminescent device and its driving method {Organic electro device and driving method of the same}

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 showing 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 light area 200: magenta light area

300: yellow light range

The present invention relates to an organic electroluminescent device and a driving method thereof, and more particularly, to an organic electroluminescent device and a driving method thereof capable of reproducing complementary colors other than the primary colors by changing the arrangement of red, green and blue pixels. will be.

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 red, green, and blue pixels as described above, as shown in FIG. 2, the color within the triangular region formed by connecting the red, green, and blue dots may be reproduced. There is a disadvantage that the color reproduction range is narrow because the color cannot be reproduced.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and the color gamut of cyan light, magenta light and yellow light in addition to the color gamut that can be reproduced as red light, green light and blue light by changing the arrangement of red, green and blue pixels. It is an object of the present invention to provide an organic electroluminescent device and a driving method thereof capable of increasing the color reproduction range by reproducing.

In order to achieve the above object, the organic light emitting display device according to the present invention,

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

At least two thin film transistors for controlling the organic light emitting element;

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 transistors;

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 region is repeatedly arranged in the order of the first pixel, the second pixel, the second pixel, the third pixel, the third pixel, and the first pixel;

The first pixel, the second pixel, and the third pixel are each of a green pixel, a blue pixel, and a red pixel;

The first pixel, the second pixel, and the third pixel are blue pixels, red pixels, and green pixels, respectively;

The first pixel, the second pixel, and the third pixel are red, green, and blue pixels, respectively,

The green pixel and the blue pixel implement the cyan light,

The red pixel and the blue pixel implement the magenta light,

The green pixel and the red pixel may implement yellow light.

In addition, the driving method of the organic light emitting display device according to the present invention in order to achieve the above object,

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

At least two thin film transistors for controlling the organic light emitting diode,

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

In the method of driving an organic electroluminescent device comprising a plurality of data lines for supplying data to the thin film transistor, and a pixel region defined by each of the scan line and the data line, including the organic light emitting device,

In the pixel area, a first pixel, a second pixel, a second pixel, a third pixel, a third pixel, and a first pixel are repeatedly arranged, and two adjacent pixels among the pixels are selectively driven to red, green, Implementing blue light, cyan light, magenta light and yellow light,

The first pixel, the second pixel, and the third pixel are each of a green pixel, a blue pixel, and a red pixel;

The first pixel, the second pixel, and the third pixel are blue pixels, red pixels, and green pixels, respectively;

The first pixel, the second pixel, and the third pixel are red, green, and blue pixels, respectively,

The red light is implemented by driving adjacent red pixels simultaneously or sequentially,

The green light may be implemented by driving adjacent green pixels simultaneously or sequentially.

The blue light is implemented by driving adjacent blue pixels simultaneously or sequentially,

The cyan light is implemented by driving green pixels and blue pixels simultaneously or sequentially;

The magenta light is implemented by driving red or blue pixels simultaneously or sequentially,

The yellow light may be implemented by driving green pixels and red pixels simultaneously or sequentially.

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) 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 pixel area. 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 pixel area. 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.

The light emitting layers may be formed in each pixel area by using a vacuum deposition method or a laser induced thermal imaging method using a fine metal mask.

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 of an organic light emitting display device according to the present invention, and is arranged in the order of a first pixel, a second pixel, a second pixel, a third pixel, a third pixel, and a first pixel. In FIG. 3, the first pixel is shown as a green pixel G, the second pixel is a blue pixel B, and the third pixel is a red pixel R. However, each pixel is formed of all colors of red, green, and blue pixels. Can be a pixel.

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 pixel is defined by the intersection of the scan line 125 and the data line 135. The scan line 125 selects a pixel to be driven, and the data line 135 serves to apply a data signal to the selected pixel.

Each 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 a data signal input through the switching thin film transistor 140. For example, the organic light emitting display may be 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 accumulated in the capacitor 145. The pixel driving thin film transistor 150 that flows current to the device 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 elements are arranged in the order of the first pixel, the second pixel, the second pixel, the third pixel, the third pixel, and the first pixel. The first pixel, the second pixel, and the third pixel may be green (G), blue (B), and red pixel (R), respectively, and blue (B), red (R), and green pixel (G). It may also be red (R), green (G) and blue pixels (B). Here, when the green pixel G and the blue pixel B are driven at the same time, the cyan color light region 100 is driven. When the blue pixel B and the red pixel R are driven at the same time, the magenta ( Magenta color region 200, and when the red pixel (R) and the green pixel (G) is driven at the same time, it becomes a yellow color region (300). As illustrated in FIG. 5, the pixels are repeatedly arranged in the order of the first pixel, the second pixel, the second pixel, the third pixel, the third pixel, and the first pixel.

In addition, the pixels constituting the pixels are arranged such that pixels of the same color as pixels forming adjacent pixels are adjacent to each other.

For example: The cyan light region 100 includes a green pixel and a blue pixel, and the magenta light region 200 adjacent to one side of the cyan light region 100 includes a blue pixel and a red pixel. Therefore, the cyan light region 100 and the magenta light region 200 are arranged so that the blue pixels are adjacent to each other. In the same manner, the yellow light region 300 adjacent to the other side of the magenta light region 200 is arranged so that the red pixels are adjacent to each other, and the cyan light region 100 adjacent to the other side of the yellow light region 300 represents the green pixel. Arrange adjacent to each other.

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.

When driving the red pixel, the green pixel, or the blue pixel, respectively, red light, green light, or blue light may be implemented. In this case, the red pixel, the green pixel, and the blue pixel each become one unit pixel.

In addition, when the green and blue pixels, the red and blue pixels, or the red and green pixels are simultaneously driven or sequentially driven within a short time, the cyan color light, the magenta color light, or the yellow color light may be driven in the above manner. Complementary colors can be implemented. In this case, in the green and blue pixels, the red and blue pixels, and the red and green pixels, two pixels become respective unit pixels.

Therefore, as shown in FIG. 6, the color gamut formed by connecting the points of red (R), green (G), blue (B), cyan (C), magenta (M), and yellow (Y) may be formed. All colors can be reproduced.

According to the present invention as described above, it is arranged in the order of the first pixel, the second pixel, the second pixel, the third pixel, the third pixel and the first pixel, driving pixels of the same color adjacent to each other or different adjacent colors. By simultaneously driving the pixels of, the primary color and the complementary color are implemented to increase the color reproduction range, and there is an advantage in that the large area of the flat panel display device is advantageous.

Claims (17)

An organic light emitting device having a first electrode and a second electrode and including an organic light emitting layer therebetween; At least two thin film transistors for controlling the organic light emitting element; 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 transistors; 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; And the pixel region is repeatedly arranged in the order of the first pixel, the second pixel, the second pixel, the third pixel, the third pixel, and the first pixel. The method of claim 1, And the first pixel, the second pixel, and the third pixel are green pixels, blue pixels, and red pixels, respectively. The method of claim 1, And the first pixel, the second pixel, and the third pixel are blue pixels, red pixels, and green pixels, respectively. The method of claim 1, The first pixel, the second pixel, and the third pixel are red pixels, green pixels, and blue pixels, respectively. The method according to any one of claims 2 to 4, And the green pixel and the blue pixel implement cyan light. The method according to any one of claims 2 to 4, And the red pixel and the blue pixel implement magenta light. The method according to any one of claims 2 to 4, And the green pixel and the red pixel implement yellow color light. An organic light emitting device having a first electrode and a second electrode and including a light emitting layer therebetween; At least two thin film transistors for controlling the organic light emitting diode, A plurality of scan lines for supplying scan signals to the thin film transistors; In the method of driving an organic electroluminescent device comprising a plurality of data lines for supplying data to the thin film transistor, and a pixel region defined by each of the scan line and the data line, including the organic light emitting device, In the pixel area, a first pixel, a second pixel, a second pixel, a third pixel, a third pixel, and a first pixel are repeatedly arranged, and two adjacent pixels among the pixels are selectively driven to red, green, A method of driving an organic electroluminescent device, comprising blue light, cyan light, magenta light, and yellow light. The method of claim 8, And the first pixel, the second pixel, and the third pixel are green pixels, blue pixels, and red pixels, respectively. The method of claim 8, And the first pixel, the second pixel, and the third pixel are blue pixels, red pixels, and green pixels, respectively. The method of claim 8, And the first pixel, the second pixel, and the third pixel are red pixels, green pixels, and blue pixels, respectively. The method according to any one of claims 8 to 11, The red light is a method of driving an organic electroluminescent device, characterized in that the adjacent red pixels are driven simultaneously or sequentially. The method according to any one of claims 8 to 11, And the green light is implemented by driving adjacent green pixels simultaneously or sequentially. The method according to any one of claims 8 to 11, And the blue light is implemented by driving adjacent blue pixels simultaneously or sequentially. The method according to any one of claims 8 to 11, The cyan light is a driving method of the organic electroluminescent device, characterized in that the green and blue pixels are driven simultaneously or sequentially. The method according to any one of claims 8 to 11, The magenta light is a method of driving an organic electroluminescent device, characterized in that the red and blue pixels are driven simultaneously or sequentially. The method according to any one of claims 8 to 11, The yellow light is a method of driving an organic electroluminescent device, characterized in that the green and red pixels are driven simultaneously or sequentially.

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