KR101547216B1 - Organic electroluminescent display device and method of driving the same - Google Patents

Abstract

The present invention relates to an organic electroluminescence panel comprising pixels composed of R (red), G (green), Bs (sky blue), and Bd (deep blue) G, and B image data corresponding to the pixel belongs to the first color area, and outputs R, G, and B image data when the R, G, and B input image data corresponding to the pixel belong to the first color area, Wherein the first R, G, and B image data correspond to the R, G, and Bs sub-pixels, respectively, and the second R, G, G, and B image data corresponding to the R, G, and B sub-pixels, respectively, and the signal processing unit performs deep color-based color coordinate transformation on the R, G, and B input image data, And generating the first R, G, and B image data by performing a sky blue-based color coordinate inverse transformation on the X, Y, and Z image data, wherein the first color area corresponds to a sky blue color area, Wherein the second color region is a region corresponding to a region excluding the sky blue region in the deep blue region It provides a light emitting display device.

Description

[0001] The present invention relates to an organic electroluminescence display device and a driving method thereof,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display, and more particularly, to an organic light emitting display and a driving method thereof.

2. Description of the Related Art [0002] With the development of an information society, demands for a display device for displaying images have been increasing in various forms. Recently, a liquid crystal display (LCD), a plasma display panel (PDP) Various flat display devices such as an organic electroluminescent display device (OELD) have been utilized.

Among these flat panel display devices, the organic light emitting display device is capable of low voltage driving, is thin, has excellent viewing angle, and has a high response speed.

In the organic light emitting display, when a data voltage is applied to a sub-pixel, a current corresponding to a data voltage value is generated and applied to the organic light emitting diode of the corresponding sub-pixel. Accordingly, the organic light emitting diode emits light having a luminance corresponding to the applied current amount.

On the other hand, the organic light emitting display device has R (red) sub-pixel, G (green) sub-pixel and B (blue) sub-pixel in order to display a color image. Organic light emitting materials emitting red, green, and blue light corresponding to the organic light emitting diodes located in each of the R sub-pixel, the G sub-pixel, and the B sub-pixel are formed. Through the combination of colors emitted from the organic luminescent material, a color image can be realized.

On the other hand, of the red, green and blue organic light emitting materials, the life time of the blue organic light emitting material is the shortest. Therefore, the lifetime of the organic electroluminescent display device is determined by the blue organic light emitting material.

Various materials can be selected and used as the blue organic light emitting material. Among them, a deep blue organic light emitting material and a sky blue organic light emitting material are widely used in conventional organic light emitting display devices.

The deep-bubble organic light emitting material has a disadvantage in that it has excellent color reproducibility but short life span. On the other hand, the sky blue organic light emitting material has the advantage that the color reproducibility is somewhat lowered, but the lifetime is long.

Therefore, in the case of a conventional organic light emitting display device using a deep-blue organic light emitting material, there is a short life span instead of excellent color reproducibility. In the case of a conventional organic electroluminescent display device using a sky blue organic light emitting material, the color reproducibility is somewhat deteriorated instead of a long lifetime.

As described above, conventional organic light emitting display devices have not satisfied both the life span and the color reproducibility.

An object of the present invention is to provide an organic electroluminescent display device having a long lifetime and excellent color reproducibility and a method of driving the same.

According to an aspect of the present invention, there is provided an organic light emitting display comprising: an organic electroluminescent panel including pixels composed of R (red), G (green), Bs (sky blue), and Bd (deep blue) G, and B image data corresponding to the pixel belongs to the first color area, and outputs R, G, and B image data when the R, G, and B input image data corresponding to the pixel belong to the first color area, Wherein the first R, G, and B image data correspond to the R, G, and Bs sub-pixels, respectively, and the second R, G, G, and B image data corresponding to the R, G, and B sub-pixels, respectively, and the signal processing unit performs deep color-based color coordinate transformation on the R, G, and B input image data, And generating the first R, G, and B image data by performing a sky blue-based color coordinate inverse transformation on the X, Y, and Z image data, wherein the first color area corresponds to a sky blue color area, Wherein the second color region is a region corresponding to a region excluding the scable color region in the deep blue region, An electroluminescence display device is provided.

Here, the signal processing unit may include a conversion unit for performing Deep Blue-based color coordinate conversion on the R, G, and B input image data to generate X, Y, and Z image data; An inverse transformation unit for performing inverse transformation of the sky blue based on the X, Y, and Z image data to generate first R, G, and B image data; A color gamut determination unit that determines whether the R, G, and B input image data belong to one of the first and second color gamuts; And a selector for selecting one of the first R, G, and B image data and the second R, G, and B image data according to the determination result of the gamut determining unit.

Wherein the signal processing unit outputs the first R, G, and B image data and the image data for causing the Bd sub-pixel to emit no light when outputting the first R, G, and B image data, When the second R, G, and B image data are output, the second R, G, and B image data and the image data for causing the non-light emission of the Bs sub-pixel to be output together.

The R, G, Bs, and Bd sub-pixels constituting the pixel may be arranged in a stripe type or quad type structure.

In another aspect, the present invention provides a method of driving an organic light emitting display device including a pixel composed of R (red), G (green), Bs (sky blue), and Bd (deep blue) Outputting first R, G, and B image data in a signal processing unit when corresponding R, G, and B input image data belong to a first color area; And outputting second R, G, and B image data, which are R, G, and B input image data, in the signal processing unit when the R, G, and B input image data belong to a second color area G and B image data correspond to the R, G and B sub-pixels, respectively, and the second R, G and B image data correspond to the R, G and B sub-pixels, respectively, The first R, G, and B image data are generated by performing a sky blue-based color coordinate inverse transformation on the X, Y, and Z image data generated by performing Deep Blue-based color coordinate conversion on the R, G, and B input image data The first color region corresponds to a sky blue color region, and the second color region corresponds to a region other than the sky blue region in the deep blue region.

The method may further include inputting the first R, G, and B image data and the second R, G, and B image data to the selection unit of the signal processing unit; Wherein the color gamut determination unit of the signal processing unit determines whether the R, G, and B input image data belong to one of the first and second color gamut regions; The selecting unit may further include selecting one of the first R, G, and B image data and the second R, G, and B image data according to the determination result of the gamut determining unit.

Outputting the first R, G, and B image data and image data for causing the Bd sub-pixel to emit no light when the first R, G, and B image data are output from the signal processing unit; ; And outputting the second R, G, and B image data and the image data for causing the non-light emission of the Bs sub-pixel to be output together when the signal processing unit outputs the second R, G, and B image data, .

The R, G, Bs, and Bd sub-pixels constituting the pixel may be arranged in a stripe type or quad type structure.

According to the present invention, it is possible to improve both color reproducibility and lifetime by selectively emitting sky blue and deep blue depending on the color gamut of input RGB image data.

When sky blue is used, the input RGB image data is converted into RGB image data so that color reproduction can be performed to the same degree as when deep blues are used, without using the input RGB image data as it is. Therefore, even if sky blue and deep blue are selected and used in two neighboring regions, it is possible to improve the occurrence of a boundary phenomenon between these two regions.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram of an organic light emitting display according to an embodiment of the present invention. FIG. 2 is an equivalent circuit diagram of a subpixel according to an embodiment of the present invention, and FIGS. Are examples of arrangement structures of sub-pixels constituting a pixel according to an example.

As shown in the figure, the organic light emitting display 100 according to the embodiment of the present invention includes an organic electroluminescence panel 200 and a driver.

In the organic electroluminescence panel 200, a plurality of gate lines GL extend in the first direction, e.g., in the row direction. A plurality of data lines DL extend in a second direction that crosses the first direction, for example, in the column direction. The plurality of gate lines GL and the plurality of data lines DL intersecting each other define a plurality of sub-pixels SP arranged in a matrix form.

2, a switching transistor TS, a driving transistor TD, an organic light emitting diode OD, and a capacitor C are formed in each subpixel SP of the organic electroluminescence panel 200 .

The switching transistor TS is connected to the corresponding gate wiring and data lines GL and DL. The driving transistor TD is connected to the switching transistor TS. For example, the gate electrode of the driving transistor TD is connected to the drain electrode of the switching transistor TS.

The organic light emitting diode OD is connected to the driving transistor TD. For example, a second electrode of the organic light emitting diode (OD), for example, a cathode, is connected to the drain electrode of the driving transistor TD. The first electrode of the organic light emitting diode OD, for example, the anode receives the first driving voltage VDD. On the other hand, an organic light-emitting layer including an organic light-emitting material for emitting light is formed between the first and second electrodes.

The capacitor C is connected between the gate electrode and the source electrode of the driving transistor TD. On the other hand, the source electrode of the driving transistor TD receives the second driving voltage VSS. For example, the source electrode of the driving transistor TD may be grounded.

For the sub-pixel SP having the above configuration, when the gate line GL is scanned and a gate signal having a turn-on voltage, for example, a gate high voltage, is applied, the switching transistor TS is turned on. Thus, the input data voltage passes through the switching transistor TS and is applied to the gate electrode of the driving transistor TD. Thus, a current is supplied to the organic light emitting diode (OD) through the driving transistor (TD) to emit light having the corresponding color.

3 to 5, the organic electroluminescent panel 200 according to the embodiment of the present invention includes R, G, Bs, and Bd sub-pixels. Here, the Bs and Bd sub-pixels are all sub-pixels that display blue, and each of them corresponds to a sub-pixel that displays blue having different color reproduction characteristics. For example, the Bs sub-pixel has a sky blue organic light emitting layer that emits sky blue light, and the Bd sub-pixel has a deep blue organic light emitting layer that emits deep blue light.

The neighboring R, G, Bs, and Bd sub-pixels constitute one pixel (P). In the exemplary embodiment of the present invention, the four R, G, Bs, and Bd sub-pixels constituting the pixel P may have various arrangement structures.

In this regard, for example, as shown in Fig. 3, it may have a stripe type arrangement structure. In the stripe type arrangement structure, R, G, Bs, and Bd sub-pixels constituting the pixel P are arranged in the row direction or the column direction. For example, the R, G, Bs, and Bd sub-pixels are arranged alternately and repeatedly in the row direction. Subpixels displaying the same color can be arranged in the same column.

Meanwhile, as shown in FIG. 4, it may have a quad type arrangement structure. In the quad type arrangement structure, R, G, Bs, and Bd sub-pixels constituting the pixel P are arranged in a matrix of 2 rows and 2 columns. The pixels P composed of such quad-type sub-pixels can be repeatedly arranged along the row direction and the column direction.

Meanwhile, the R, G, Bs, and Bd subpixels of FIG. 5 may also have a quad type arrangement structure. However, the quad type arrangement structure of Fig. 5 differs from the quad type arrangement structure of Fig. For example, two pixels neighboring each other along the column direction, that is, the first and second pixels P1 and P2, are symmetrical with respect to the row direction. That is, Bs and Bd sub-pixels are arranged in the first row of the first pixel P1, and these sub-pixels are arranged in the second row of the second pixel P2. The R and G sub-pixels are arranged in the second row of the first pixel P1, and these sub-pixels are arranged in the first row of the second pixel P2.

3 to 5 are examples, and it is apparent to those skilled in the art that sub-pixels may be arranged in various other forms.

The driving unit for driving the organic electroluminescence panel 200 may include a timing control unit 310, a gate driving unit 320, a data driving unit 330, and a signal processing unit 400.

The timing controller 310 responds to a control signal input from an external system such as a video card and supplies a gate control signal GCS for controlling the gate driver 320 and a data control signal DCS Can be generated. Meanwhile, the timing controller 310 receives the RGBsBd image data output from the signal processor 400, arranges the RGBsBd image data, and performs data processing, if necessary.

Here, R image data, G image data, Bs image data, and Bd image data correspond to signals corresponding to R subpixel, G subpixel, Bs subpixel, and Bd subpixel, respectively.

The data driver 330 generates a data voltage corresponding to the input image data RGBsBd in response to the data control signal DCS supplied from the timing controller 310 and outputs it to the corresponding data line DL . Such a data voltage is generated using gamma voltages. As described above, the data driver 330 converts the image data of the digital format into a data voltage of an analog format and outputs the data.

The gate driver 320 can sequentially select the gate line GL in response to the gate control signal GCS supplied from the timing controller 310. [ For the selected gate wiring GL, a gate signal having a turn-on voltage is outputted. Thus, the switching transistor TS of the sub-pixel SP connected to the selected gate line GL is turned on. In synchronization with this, the data voltage is outputted to the data line DL and inputted to the corresponding sub-pixel SP.

The data voltage input to the sub-pixel SP passes through the switching transistor TS and is applied to the gate electrode of the driving transistor TD. Accordingly, a current corresponding to the applied data voltage value flows through the driving transistor TD, which is applied to the organic light emitting diode OD. As a result, the organic light emitting diode OD emits light having a brightness corresponding to the applied current value.

The signal processing unit 400 receives, for example, RGB image data as source image data from an external system and outputs RGBsBd image data corresponding thereto.

Here, in the embodiment of the present invention, one of the Bs subpixel and the Bd subpixel constituting each pixel P and displaying blue is selected and driven. That is, when the Bs sub-pixel is selected to emit light, the light emission of the Bd sub-pixel is turned off. When the Bd sub-pixel is selected to emit light, the light emission of the Bs sub-pixel is turned off.

Accordingly, when the Bs sub-pixel is selected and lighted, the signal processing unit 400 outputs the Bd image data so as to have a default value so that the Bd sub-pixel does not emit light. When the Bd sub-pixel is selected and emits light, the signal processing unit 400 outputs the Bs video data so as to have a default value so that the Bs sub-pixel is not emitted. Such a default value is a value for causing the corresponding sub-pixel to express black gradation, and corresponds to a value for preventing the corresponding sub-pixel from being turned on.

As described above, the operation of selecting one of the Bs sub-pixel for displaying sky blue and the Bd sub-pixel for displaying the deep blue is related to the color to be reproduced in the pixel P concerned. In this regard, FIG. 6 will be further described with reference to FIG.

6 is a diagram showing a CIE 1931 color coordinate system.

Referring to FIG. 6, when sky blue is used, a color reproduction area that can be represented, that is, a sky blue color area corresponds to the first color area C1. That is, when the R sub-pixel, the G sub-pixel, and the Bs sub-pixel are used, the colors included in the first color region C1 can be reproduced.

On the other hand, when the deep well is used, the color region that can be represented, that is, the deep blue region corresponds to the third color region C3. That is, when the R sub-pixel, the G sub-pixel, and the Bd sub-pixel are used, the colors included in the third color region C3 can be reproduced. On the other hand, in general, regarding yellowness, when y value is 0.15 or more, it corresponds to sky blue, and when it is less than 0.15, it corresponds to deep blue.

It can be seen that the color of the third color region C3 can be reproduced in a wider range than that of the first color region C1. For example, the first color region C1 has a region defined by "a-b-c", and the third color region C3 has a region defined by "a-d-c".

Accordingly, it can be seen that the range of colors that can be expressed through the pixel P when deep blues are used becomes wider than the range of colors that can be expressed through the pixels P when the sky blue is used . That is, in the case of using Sky Blue, the area defined by the second color area C2, i.e., "b-d-c ", which can be expressed in the case of using the deep blue, can not be expressed.

Accordingly, when the color to be represented by the input RGB image data belongs to the first color gamut C1, such a color can be expressed using sky blue, and also expressed using deep blue.

However, if the color to be represented by the input RGB image data does not belong to the first color gamut C1 but belongs to the third color gamut C3, that is, belongs to the second color gamut C2, Such a color can not be expressed using sky blue, but it is expressed by using deep blue.

As described above, in consideration of the degree of color reproduction of sky blue and the degree of color reproduction of deep deep, in the embodiment of the present invention, when the color to be represented by the pixel P belongs to the second color area by the inputted RGB image data , Deep blues are used. When the color to be represented by the input RGB image data belongs to the first color gamut C1, sky blue is used.

In other words, when the color to be represented by the input RGB image data belongs to the second color region C2, the Bd sub-pixel expressing the deep blue is caused to emit light. When the color to be represented by the input RGB image data belongs to the first color gamut C1, the Bs sub-pixel that expresses the sky blue emits light.

As described above, the Bs sub-pixel and the Bd sub-pixel of the pixel P are selectively emitted according to the color of the RGB image data. That is, with respect to a color that can be represented by both sky blue and deep blue, a Bs sub-pixel having a long lifetime is emitted without using a Bd sub-pixel having a short lifetime, and sky blue is used. For the colors not represented by Sky Blue but represented only by the deep blue, the Bd sub-pixel is caused to emit light without causing the Bs sub-pixel to emit light. On the other hand, deep blues are required mainly for displaying moving images, which are required only in a part of a moving picture screen which is generally displayed. Therefore, the frequency of using the Bd sub-pixel is not high.

As described above, in the embodiment of the present invention, the Bs sub-pixel and the B d sub-pixel are selectively made to emit light for each pixel P in accordance with the color gamut to which the corresponding RGB video data belongs, .

As described above, in the embodiment of the present invention, the Bs subpixel and the Bd subpixel are selectively made to emit light. Accordingly, in displaying an image, a region in which Sky Blue is used and a region in which a deep- can do. In this regard, FIG. 7 will be further described with reference to FIG.

7 is a photograph showing an image expressed by the input RGB image data and an image expressed by RGBsBd image data. Here, the image on the left corresponds to the image to be displayed by the input RGB image data. The right image corresponds to the image expressed when the input RGB image data is directly used as RGBs image data or RGBd image data according to the color region.

In this case, if we look at the image on the right side, we can see that the boundary phenomenon occurs in the sky background on the upper side. This boundary phenomenon is caused by sky blue being used for the lower region of the boundary, and deep lake used for the upper region of the boundary. That is, the above-described boundary phenomenon can occur between the area where sky blue is used and the area where deep blue is used.

This boundary phenomenon is unusual in that the color reproduction characteristics of the pixel P when Sky Blue is used and the color reproduction characteristics of the pixel P when the deep blue is used are different.

In this regard, in expressing colors, the luminance ratio of red (R), green (G), and blue (B) in the pixel P in which Sky Blue is used and in the pixel P in which the deep blue is used are different from each other. For example, the blue luminance ratio in the pixel P in which sky blue is used is higher than the blue luminance ratio in the pixel P in which the deep blue is used.

As described above, there is a difference in luminance ratio between the case of using sky blue and the case of using deep blue, that is, a difference in color reproduction characteristics. Therefore, when using the same RGB image data directly, there is a difference in color and luminance between the image displayed when using sky blue and the image displayed when using deep blue.

Due to such a difference in color reproduction characteristics, luminance unevenness and relative color shift are caused between a region where sky blue is used and a region where deep blue is used in a displayed image. As a result, a boundary phenomenon occurs in which the two regions are displayed separately from each other.

In order to solve such a boundary phenomenon, in the embodiment of the present invention, RGBs image data is converted into RGBs so that the pixel P in which Sky Blue is used can achieve the same color reproduction as that of the pixel P in which the deep- . For example, RGBs image data is generated for the pixel P in which sky blue is used, so that the input RGB image data is not directly used as RGBs image data but the color and brightness when deep blues are used can be realized .

Hereinafter, as described above, the operation of the signal processing unit 400 that allows the sky blue and deep blues to be selectively used according to the color gamut, and pixels using Sky Blue can reproduce colors of pixels using deep blues Will be described with reference to Fig.

8 is a diagram schematically showing an example of a configuration of a signal processing unit according to an embodiment of the present invention.

8, a signal processing unit 400 according to an embodiment of the present invention includes a converting unit 410, an inverse transforming unit 420, a color gamut determining unit 430, a selecting unit 440, And an output unit 450.

The RGB image data R_in, G_in, and B_in (hereinafter, referred to as RGB input image data) input to the signal processing unit 400 are converted into RGB image data by the conversion unit 410 .

The RGB input image data R_in, G_in, and B_in may be input to the selection unit 440 and the color gamut determination unit 430. Here, the RGB input image data R_in, G_in, and B_in input to the selection unit 440 may be referred to as second RGB image data R_d, G_d, and B_d for convenience of explanation. The first RGB image data R_d, G_d, and B_d correspond to the image data for driving the R, G, and Bd subpixels of the corresponding pixel P in the case where the deep blur is selected in the corresponding pixel P do.

The conversion unit 410 performs color coordinate conversion on the RGB input image data R_in, G_in, and B_in, and outputs the converted image data (X, Y, Z). For example, the converting unit 410 converts the RGB signals of the RGB color coordinate system into the XYZ signals of the XYZ color coordinate system.

In converting the color coordinate system by the conversion unit 410, the data conversion, i.e., data mapping, of the conversion unit 410 may be performed by applying a color coordinate transformation in the case of using deep blues. That is, when the RGB input image data R_in, G_in, and B_in are implemented as pixels P using the deep well, -to-XYZ color coordinate conversion. Such color coordinate conversion is performed, for example,

... 변환식 (1)

... conversion formula (1)

(1), < / RTI > Here, Md corresponds to a conversion matrix for converting an RGB signal to an XYZ signal when a deep well is used. Here, for convenience of explanation, the RGB-to-XYZ color coordinate conversion when the deep color is used can be referred to as deep color-based color coordinate conversion. A lookup table (LUT) for such deep-based color coordinate transformation is provided in the conversion unit 410, and XYZ image data mapping for the RGB input image data R_in, G_in, and B_in can be automatically performed.

The XYZ image data generated as described above is input to the inverse transform unit 420. [

The inverse transform unit 420 performs inverse transform of the color coordinate with respect to the input XYZ image data to output the converted RGB image data R_s, G_s, and B_s. For example, the inverse transform unit 420 converts the XYZ signal of the XYZ color coordinate system into the RGB signal of the RGB color coordinate system.

In this way, the inverse transform unit 420 transforms the color coordinate system, and the data transformation process of the inverse transform unit 420 applies the inverse color coordinate transformation in the case where sky blue is used. That is, when the input XYZ image data is implemented as a pixel P using sky blue, the image data corresponding to the color reproduction characteristics of the pixel P driving the sky blue is converted into XYZ-to-RGB Thereby performing color coordinate inverse transform. Such a color coordinate inverse transformation is performed, for example,

... 변환식 (2)

... conversion formula (2)

(2), < / RTI > Here, Ms corresponds to a conversion matrix for converting an RGB signal into an XYZ signal when sky blue is used. Accordingly, Ms ^-1 corresponds to an inverse transformation matrix for inversely transforming the XYZ signal into the RGB signal when sky blue is used. Here, for convenience of explanation, the inverse transformation of the XYZ-to-RGB color coordinate when sky blue is used can be referred to as sky blue-based color coordinate inverse transformation. On the other hand, a lookup table (LUT) for inverse transformation of the sky blue-based color coordinate is provided in the inverse transform unit 420, and mapping of the RGB image data R_s, G_s, B_s to the inputted XYZ image data can be performed automatically .

Here, the RGB image data R_s, G_s, and B_s output from the inverse transform unit 420 may be referred to as first RGB image data for convenience of explanation. When the sky blue is selected for the corresponding pixel P, the first RGB image data R_s, G_s, and B_s are used to drive the R, G, and Bs sub-pixels of the corresponding pixel P Corresponds to image data.

As described above, the deep-blue-based color coordinate transformation is performed on the RGB input image data R_in, G_in, and B_in, and then the inverse transformation of the sky blue based color coordinate is performed to obtain the first RGB image data (R_s, G_s, B_s).

Accordingly, the first RGB image data R_s, G_s, and B_s for sky blue use can have the same XYZ color coordinate values as the second RGB image data R_d, G_d, and B_d for deep use. This means that the same color and brightness can be realized in the case of using sky blue and the case of using deep blue for the same RGB input image data R_s, G_s and B_s. That is, the pixel P using sky blue means that color reproduction can be performed as if it is a pixel P using a deep well. Therefore, even if sky blue and deep blue are selected and used in two neighboring regions, the boundary phenomenon occurring in the right image of FIG. 7 can be improved.

The selection unit 440 selects one of the RGB input image data R_in, G_in and B_in, that is, the second RGB image data R_d, G_d and B_d, and the first RGB image data R_s , G_s, and B_s). The selection unit 440 selects the first RGB image data R_s, G_s and B_s and the second RGB image data R_d, G_d and B_d in response to the determination result of the color region determination unit 430 And selects one of the input two pieces of RGB image data.

In this regard, the color gamut determination unit 430 determines whether the RGB input image data R_in, G_in, B_in belongs to the sky blue region C1 or the first color region C1 shown in FIG. 6, Or whether it belongs to the color region C2, i.e., the second color region C2, which is expressed only by the deep blur of the deep blue region.

If it is determined that the RGB input image data R_in, G_in, and B_in belong to the first color region C1 as a result of the determination by the color region determination unit 430, the selection signal corresponding to the RGB input image data R_in, G_in, and B_in is output. In response to such a selection signal, the selection unit 440 selects and outputs the first RGB video data R_s, G_s, and B_s.

On the other hand, if it is determined to belong to the second color gamut C2 as a result of the determination of the color gamut determination unit 430, the corresponding selection signal is output. In response to such a selection signal, the selection unit 440 selects and outputs the second RGB video data R_d, G_d, and B_d.

As described above, the selection unit 440 selects and outputs the corresponding video data in response to the selection signal of the color gamut determination unit 430. The RGB image data (R_out, G_out, B_out) output from the selection unit 440 is input to the output unit 450.

Meanwhile, in the above description, the color gamut determination unit 430 receives the RGB input image data R_in, G_in, and B_in and performs color gamut determination. On the other hand, the color gamut determination unit 430 may receive the XYZ image data output from the conversion unit 410 and perform color gamut determination.

The color gamut determination unit 430 extracts x and y color coordinate values from the inputted RGB input image data R_in, G_in, B_in or XYZ image data, it can be determined whether the x, y color coordinate values belong to the first color gamut C1 or the second color gamut C2.

The output unit 450 can output other B video data to the input RGB video data R_out, G_out and B_out. In this regard, when the input RGB image data R_out, G_out, and B_out are the first RGB image data R_s, G_s, and B_s, the Bs sub-pixel among the Bs and Bc sub-pixels of the corresponding pixel P Is selected and driven. Accordingly, a value for non-emission of the Bd sub-pixel which is not selected, for example, a video data having a default value, should be allocated for the Bd sub-pixel. In this case, the output unit 450 outputs the input RGB image data R_out, G_out, and B_out as RGBs image data R_out, G_out, and Bs_out, and outputs Bd image data having a default value Bd_out) can be added and output.

On the other hand, when the input RGB image data R_out, G_out, and B_out are the second RGB image data R_d, G_d, and B_d, the Bs and Bd subpixels of the corresponding pixel P, Pixels are selected and driven. Accordingly, a value for non-emission of the unselected Bs sub-pixel, for example, image data having a default value, should be allocated for the Bs sub-pixel. In this case, the output unit 450 outputs the input RGB image data R_out, G_out, and B_out as the RGBd image data R_out, G_out, and Bd_out, and adds the Bs image data having the default value Bs_out) can be added and output.

The function of outputting the function of the output unit 450 as described above, that is, adding the Bs image data Bs_out or Bd image data Bd_out having the default value to the input image data R_out, G_out, B_out, And may be configured in the selection unit 440. For example, when the first RGB image data R_s, G_s, and B_s are selected, the selector 440 may add and output Bd image data having a default value. When the second RGB video data R_d, G_d, and B_d are selected, the selection unit 440 may add and output Bs video data having a default value.

9 is a photograph showing an image displayed when RGB input image data is directly used as RGBs image data or RGBd image data according to a color gamut, and an image displayed when signal processing according to FIG. 8 is performed.

In such a case, as shown in FIG. 7, it can be seen that a boundary phenomenon occurs in the sky background on the upper side. In other words, it can be confirmed that a boundary is generated between the area where Sky Blue is used and the area where the deep portion is used.

On the other hand, if we look at the image on the right side, it can be confirmed that the boundary phenomenon in the left image is eliminated. This is an effect of adjusting the RGB input image data so that the pixels of the region where sky blue is used can perform color reproduction as much as the pixels of the region where the deep blue is used, as described above.

The embodiment of the present invention described above is an example of the present invention, and variations are possible within the spirit of the present invention. Accordingly, the invention includes modifications of the invention within the scope of the appended claims and equivalents thereof.

1 is a schematic view illustrating an organic light emitting display according to an embodiment of the present invention.

2 is an equivalent circuit diagram of a sub-pixel according to an embodiment of the present invention;

FIGS. 3 to 5 are views showing examples of a layout structure of sub-pixels constituting a pixel according to an embodiment of the present invention; FIG.

6 shows a CIE 1931 color coordinate system.

FIG. 7 is a photograph showing an image expressed by input RGB image data and RGBsBd image data; FIG.

8 is a view schematically showing an example of a configuration of a signal processing unit according to an embodiment of the present invention;

9 is a photograph showing an image displayed when RGB input image data is directly used as RGBs image data or RGBd image data according to a color gamut, and a picture displayed when signal processing according to FIG. 8 is performed.

Description of the Related Art

400: signal processing unit 410:

420: Inverse transform unit 430: Color gamut determination unit

440: selection unit 450: output unit

Claims (8)

An organic electroluminescent panel including pixels composed of R (red), G (green), Bs (sky blue), and Bd (deep blue) G, and B image data corresponding to the pixel belongs to the first color area, and outputs R, G, and B image data when the R, G, and B input image data corresponding to the pixel belong to the first color area, And a signal processing unit for outputting second R, G, and B image data that are input image data, Wherein the first R, G, and B image data correspond to the R, G, and Bs sub-pixels, respectively, the second R, G, and B image data correspond to the R, G, and B sub- The signal processing unit performs Deep Blue-based color coordinate transformation on the R, G, and B input image data to generate X, Y, and Z image data, and performs inverse conversion of the sky blue based on the X, Y, and Z image data To generate the first R, G, and B image data, The first color area corresponds to a color area expressed using sky blue, red and green, Wherein the second color region is a region corresponding to a region except for the first color region in a color region expressed by using a deep well, Organic electroluminescence display device. The method according to claim 1, The signal processing unit, A conversion unit for performing X-axis, Y-axis, and Z-axis image data on the R, G, and B input image data by performing Deep Blue-based color coordinate conversion; An inverse transformation unit for performing inverse transformation of the sky blue based on the X, Y, and Z image data to generate first R, G, and B image data; A color gamut determination unit that determines whether the R, G, and B input image data belong to one of the first and second color gamuts; And a selector for selecting one of the first R, G, and B image data and the second R, G, and B image data according to a determination result of the color gamut determination unit Organic electroluminescence display device. The method according to claim 1, The signal processing unit, And outputs the first R, G, and B image data and the image data for causing the Bd sub-pixel to emit no light when outputting the first R, G, and B image data, When the second R, G, and B image data are output, the second R, G, and B image data and the image data for causing the non-light emission of the Bs sub-pixel to be output together Organic electroluminescence display device. The method according to claim 1, And R, G, Bs, and Bd sub-pixels constituting the pixel are arranged in a stripe type or quad type structure. A method of driving an organic light emitting display device including pixels composed of R (red), G (green), Bs (sky blue), and Bd (deep blue) Outputting first R, G, and B image data in a signal processing unit when R, G, and B input image data corresponding to the pixel belong to a first color area; And outputting second R, G and B image data, which are R, G and B input image data, in the signal processing unit when the R, G and B input image data belong to a second color area , Wherein the first R, G, and B image data correspond to the R, G, and Bs sub-pixels, respectively, the second R, G, and B image data correspond to the R, G, and B sub- The first R, G, and B image data are generated by performing deep blue transformation based on the sky blue on the X, Y, and Z image data generated by performing Deep Blue-based color coordinate conversion on the R, G, And, The first color area corresponds to a color area expressed using sky blue, red and green, Wherein the second color region is a region corresponding to a region except for the first color region in a color region expressed by using a deep well, A method of driving an organic electroluminescent display device. 6. The method of claim 5, Inputting the first R, G, and B image data and the second R, G, and B image data to a selection unit of the signal processing unit; Wherein the color gamut determination unit of the signal processing unit determines whether the R, G, and B input image data belong to one of the first and second color gamut regions; And selecting one of the first R, G, and B image data and the second R, G, and B image data according to a determination result of the gamut determining unit Wherein the organic light emitting display device further comprises: 6. The method of claim 5, Outputting the first R, G, and B image data and image data for causing the Bd sub-pixel to emit no light when the first R, G, and B image data are output from the signal processing unit; ; And outputting the second R, G, and B image data and the image data for causing the non-light emission of the Bs sub-pixel together when the signal processing unit outputs the second R, G, and B image data, Wherein the organic light emitting display device further comprises: 6. The method of claim 5, Wherein the R, G, Bs, and Bd sub-pixels constituting the pixel are arranged in a stripe type or quad type structure.

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