KR20110070176A - Organic electroluminescent display device and method of driving the same - Google Patents

Abstract

PURPOSE: An organic electroluminescent display device and a method of driving the same are provided to improve the color reproducibility and lifespan by selectively radiating sky blue and deep blue. CONSTITUTION: In an organic electroluminescent display device and a method of driving the same, A transform unit(410) performs deep blue based color coordinate transformation of an R,G,B input image data The transform unit generates X,Y,Z image data. A reverse transform unit(420) performs sky blue based color coordinate transformation of the X,Y,Z image data The reverse transforms unit generates first R,G,B image data. A color region determination unit(430) determines which region of a first and second color region R,G,B input image data is included in. A selection unit(440) selects one of the first R,G,B image data and the second R,G,B image data.

Description

Organic electroluminescent display device and method of driving the same

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device and a driving method thereof.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. Recently, liquid crystal displays (LCDs), plasma display panels (PDPs), organic fields Various flat display devices such as organic electroluminescent display devices (OELD) are being utilized.

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

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

On the other hand, the organic light emitting display device includes an R (red) subpixel, a G (green) subpixel, and a B (blue) subpixel to display a color image. The organic light emitting diodes positioned in each of the R subpixels, the G subpixels, and the B subpixels are configured with organic light emitting materials for emitting corresponding red, green, and blue colors. Through the combination of colors emitted from the organic light emitting material, it is possible to implement a color image.

Meanwhile, among the red, green, and blue organic light emitting materials, the life of the blue organic light emitting material is the shortest. Therefore, the lifetime of the organic light emitting display device is determined by the blue organic light emitting material.

Various materials may be selected and used as such a blue organic light emitting material. Among these, deep blue organic light emitting materials and sky blue organic light emitting materials are used in a conventional organic light emitting display device.

Here, the deep blue organic light emitting material has excellent disadvantages of color reproducibility but short lifespan. On the other hand, the sky blue organic light emitting material has a merit that the color reproducibility is slightly reduced, but the life is long.

Therefore, the conventional organic light emitting display device using the deep blue organic light emitting material has a short lifespan instead of having excellent color reproducibility. In the case of the conventional organic light emitting display device using the sky blue organic light emitting material, there is a problem in that the color reproducibility is slightly decreased while the life is long.

As such, the conventional organic light emitting display device does not satisfy both lifetime and color reproducibility.

The present invention has a problem to provide an organic light emitting display device having a long lifetime and excellent color reproducibility and a driving method thereof.

In order to achieve the above object, the present invention, the organic light emitting panel including a pixel consisting of R (red), G (green), Bs (sky blue), Bd (deep blue) sub-pixel; When the R, G, and B input image data corresponding to the pixel belong to the first color gamut, the first R, G, and B image data are output, and when the R, G, and B input image data belong to the second color gamut, And a signal processor for outputting second R, G, and B image data, which are input image data, wherein the first R, G, and B image data correspond to the R, G, and Bs subpixels, respectively. , G and B image data respectively correspond to the R, G, and Bd subpixels, and the signal processor performs deep blue based color coordinate transformation on the R, G, and B input image data to perform X, Y, and Z image data. And generate 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 gamut corresponds to a sky blue color gamut, The second color gamut corresponds to a region of the deep blue gamut excluding the sky blue gamut. An electroluminescent display device is provided.

The signal processor may include: a converter configured to perform deep blue based color coordinate transformation on the R, G, and B input image data to generate X, Y, and Z image data; An inverse transform unit generating first R, G, and B image data by performing sky blue-based color coordinate inverse transform on the X, Y, and Z image data; A color gamut determination unit configured to determine which of the first and second color gamuts belong to the R, G, and B input image data; The color gamut determination unit may include a selection unit to select one of the first R, G, and B image data and the second R, G, and B image data.

The signal processor, when outputting the first R, G, B image data, outputs the first R, G, B image data and the image data to non-emitting the Bd subpixel, When outputting the second R, G, and B image data, the second R, G, and B image data and the image data for non-emitting the Bs subpixel may be output together.

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

In another aspect, the present invention is a driving method of an organic light emitting display device comprising a pixel composed of R (red), G (green), Bs (sky blue), Bd (deep blue) sub-pixels, Outputting first R, G, and B image data by the signal processor when corresponding R, G, and B input image data belong to the first color gamut; If the R, G, B input image data belongs to a second color gamut, outputting, by the signal processor, second R, G, B image data which is the R, G, B input image data; The first R, G, and B image data correspond to the R, G, and Bs subpixels, and the second R, G, and B image data respectively correspond to the R, G, and Bd subpixels. The first R, G, and B image data are generated by performing a sky blue based color coordinate inverse transform on the X, Y, and Z image data generated by performing deep blue based color coordinate transformation on the R, G, and B input image data. The first color gamut corresponds to a sky blue color gamut, and the second color gamut provides a method of driving an organic light emitting display device corresponding to an area excluding the sky blue gamut from a deep blue gamut.

Inputting the first R, G and B image data and the second R, G and B image data to a selector of the signal processor; Determining, by the color gamut determination unit of the signal processing unit, which of the first and second color gamuts belong to the R, G, and B input image data; 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 color gamut determination unit.

Outputting the first R, G, and B image data together with the image data to non-emit the Bd subpixel when the signal processing unit outputs the first R, G, and B image data; ; When the signal processor outputs the second R, G, and B image data, outputting the second R, G, and B image data together with the image data which causes the Bs subpixel to be non-emitted. It may further include.

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

In the present invention, by selectively emitting the sky blue and deep blue in accordance with the color gamut of the input RGB image data, both color reproducibility and life can be improved.

When the sky blue is used, the input RGB image data is converted so that the same color reproduction as in the case of deep blue is performed without using the input RGB image data as it is. As a result, even if sky blue and deep blue are selected and used in two neighboring areas, it is possible to improve the occurrence of a boundary phenomenon between these two areas.

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

1 is a view schematically illustrating an organic light emitting display device 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. 3 to 5 are embodiments of the present invention. FIG. 7 is a diagram illustrating examples of an arrangement structure of subpixels constituting a pixel.

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

In the organic light emitting panel 200, a plurality of gate lines GL extend in a first direction, for example, in a row direction. A plurality of data lines DL extend in a second direction, for example, a column direction, which intersects the first direction. As described above, the plurality of gate lines GL and the plurality of data lines DL that cross each other define a plurality of subpixels SP arranged in a matrix form.

Referring to FIG. 2, each subpixel SP of the organic light emitting panel 200 includes a switching transistor TS, a driving transistor TD, an organic light emitting diode OD, and a capacitor C. Can be.

The switching transistor TS is connected to the corresponding gate line and data line 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, for example, a cathode, of the organic light emitting diode OD is connected to the drain electrode of the driving transistor TD. The first electrode, for example, an anode of the organic light emitting diode OD receives the first driving voltage VDD. On the other hand, between the first and second electrodes, an organic light emitting layer including an organic light emitting material for emitting light is configured.

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.

When the gate wiring GL is scanned and a gate signal having a turn-on voltage, for example, a gate high voltage, is applied to the subpixel SP having the above configuration, the switching transistor TS is turned on. Accordingly, the input data voltage passes through the switching transistor TS and is applied to the gate electrode of the driving transistor TD. As a result, the current passes through the driving transistor TD and is supplied to the organic light emitting diode OD to emit light having a corresponding color.

3 to 5, the organic light emitting panel 200 according to the embodiment of the present invention includes R, G, Bs, and Bd subpixels. Here, the Bs and Bd subpixels are all subpixels displaying blue, and each of the Bs and Bd subpixels corresponds to a subpixel displaying blue having different color reproduction characteristics. For example, the Bs subpixel has a skyblue organic light emitting layer emitting sky blue light, and the Bd subpixel has a deep blue organic light emitting layer emitting deep blue light.

The neighboring R, G, Bs, and Bd subpixels constitute one pixel P. In the embodiment of the present invention, four R, G, Bs, and Bd subpixels constituting the pixel P may have various arrangement structures.

In this regard, for example, as shown in FIG. 3, a stripe type arrangement may be provided. In the stripe type arrangement structure, the R, G, Bs, and Bd subpixels constituting the pixel P are arranged along the row direction or the column direction. For example, subpixels R, G, Bs, and Bd are alternately arranged alternately along the row direction. Subpixels displaying the same color may be arranged in the same column.

On the other hand, as shown in Figure 4, it may have a quad type (quad type) arrangement structure. In the quad type arrangement structure, the R, G, Bs, and Bd subpixels constituting the pixel P are arranged in a two-row, two-column matrix. The pixel P including the quad type subpixels may 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. However, the quad type arrangement structure of FIG. 5 is different from the quad type arrangement structure of FIG. 4. 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 subpixels are disposed in a first row of the first pixel P1, and such subpixels are disposed in a second row of the second pixel P2. In addition, R and G subpixels are disposed in a second row of the first pixel P1, and such subpixels are disposed in a first row of the second pixel P2.

Meanwhile, the arrangement of the subpixels illustrated in FIGS. 3 to 5 is one example, and it is apparent to those skilled in the art that the subpixels may be arranged in various forms.

The driving unit for driving the organic light emitting panel 200 may include a timing controller 310, a gate driver 320, a data driver 330, and a signal processor 400.

In response to a control signal input from an external system such as a video card, the timing controller 310 controls the gate control signal GCS for controlling the gate driver 320 and the data control signal DCS for controlling the data driver 330. ) Can be created. On the other hand, the timing controller 310 receives the RGBsBd image data output from the signal processor 400 and arranges them, and may perform data processing as necessary.

Here, the R image data, the G image data, the Bs image data, and the Bd image data correspond to signals corresponding to the R subpixel, the G subpixel, the Bs subpixel, and the 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 the data voltage to the corresponding data wiring DL. Done. This data voltage is generated using gamma voltages. In this way, the data driver 330 converts the video data of the digital format into the data voltage of the analog format and outputs the data voltage.

The gate driver 320 may sequentially select the gate wiring GL in response to the gate control signal GCS supplied from the timing controller 310. The gate signal having the turn-on voltage is output to the selected gate wiring GL. Accordingly, the switching transistor TS of the subpixel SP connected to the selected gate line GL is turned on. In synchronization with this, a data voltage is output to the data wiring DL and input to the corresponding subpixel SP.

The data voltage input to the subpixel 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 luminance corresponding to the applied current value.

The signal processor 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 configured in each pixel P and displaying blue is selected and driven. In other words, when the Bs subpixel is selected to emit light, the light emission of the Bd subpixel is turned off. When the Bd subpixel is selected to emit light, the light emission of the Bs subpixel is turned off.

Accordingly, when the Bs subpixel is selected to emit light, the signal processor 400 outputs the Bd image data to have a default value so that the Bd subpixel does not emit light. When the Bd subpixel is selected to emit light, the signal processor 400 outputs the Bs video data to have a default value so that the Bs subpixel does not emit light. Such a default value is a value that causes the subpixel to express black gradation, and corresponds to a value such that the subpixel does not turn on.

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

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

Referring to FIG. 6, when sky blue is used, the color reproducible area, that is, the sky blue color area, corresponds to the first color area C1. That is, when using the R subpixel, the G subpixel, and the Bs subpixel, colors included in the first color gamut C1 can be reproduced.

Meanwhile, when deep blue is used, the color gamut that can be expressed, that is, the deep blue gamut corresponds to the third color gamut C3. That is, when the R subpixel, the G subpixel, and the Bd subpixel are used, colors included in the third color gamut C3 may be reproduced. On the other hand, conventionally, in relation to blue, when the y value is 0.15 or more, it corresponds to sky blue, and when it is less than, it corresponds to deep blue.

However, it can be seen that the third color gamut C3 can reproduce colors in a wider range than the first color gamut C1. For example, the first color gamut C1 has an area defined as "a-b-c", and the third color gamut C3 has an area defined as "a-d-c".

Accordingly, it can be seen that the range of colors that can be expressed through the pixel P when using deep blue is wider than the range of colors that can be expressed through the pixel P when using sky blue. . That is, when using sky blue, the second color gamut C2 that can be expressed when deep blue is used, that is, the area defined by “b-d-c” cannot be expressed.

Accordingly, when the color to be expressed by the input RGB image data belongs to the first color gamut C1, such a color may be expressed using sky blue and also 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 cannot be expressed using sky blue, but only deep blue.

As described above, in consideration of the degree of color reproduction of the sky blue and the degree of color reproduction of the deep blue, in the embodiment of the present invention, when the color to be expressed by the pixel P belongs to the second color gamut by the input RGB image data. Deep Blue is used. When the color to be expressed 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 gamut C2, the Bd subpixel representing deep blue is made to emit light. When the color to be expressed by the input RGB image data belongs to the first color gamut C1, the Bs subpixel representing sky blue is made to emit light.

As such, the Bs subpixel and the Bd subpixel of the pixel P are selectively emitted according to the color to be expressed by the RGB image data. In other words, for the color that can be expressed by both sky blue and deep blue, sky blue is used by emitting a long lifetime Bs subpixel without emitting light having a short lifetime Bd subpixel. And for the color expressed only in deep blue, not in the sky blue, the Bd subpixel is made to emit light without emitting the Bs subpixel. On the other hand, deep blue is mainly required when displaying a video, but is required only in a part of a video screen which is generally displayed. Therefore, the frequency of using the Bd subpixel is not high.

As described above, in the embodiment of the present invention, for each pixel P, the Bs subpixel and the Bd subpixel are selectively emitted according to the color gamut to which the corresponding RGB image data belongs, thereby simultaneously achieving color reproducibility and lifetime. It can be improved.

Meanwhile, as described above, in the embodiment of the present invention, the Bs subpixel and the Bd subpixel are selectively emitted. Accordingly, in displaying an image, an area in which sky blue is used and an area in which deep blue are used coexist. can do. In this regard, it will be described with reference to FIG. 7 further.

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

In this case, looking at the image on the right, it can be seen that the boundary phenomenon occurs in the sky background of the upper side. This boundary phenomenon is caused by using sky blue in the lower region of the boundary and deep blue in the upper region of the boundary. That is, the above boundary phenomenon may occur between the area where the sky blue is used and the area where the 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 deep blue are used are different.

In this regard, in expressing colors, the luminance ratios of red, green, and blue in the pixel P in which sky blue is used and the pixel P in which deep blue are 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 deep blue is used.

As such, there is a difference in luminance ratio, that is, a difference in color reproduction characteristics, when Sky Blue is used and when Deep Blue is used. Therefore, when the same RGB image data is directly used, 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, a luminance imbalance and a relative color shift are caused between a region where sky blue is used and a region where deep blue is used in the displayed image. As a result, a boundary phenomenon occurs in which the two areas are divided and displayed.

In order to improve such a boundary phenomenon, in the embodiment of the present invention, RGBs image data is generated so that the pixel P using sky blue can achieve the same color reproduction as the pixel P using deep blue. Create For example, for the pixel P using sky blue, RGBs image data is generated so that color and luminance when deep blue is used can be generated without directly using the input RGB image data as RGB image data. Done.

Hereinafter, as described above, the operation of the signal processor 400 to selectively use the sky blue and deep blue according to the color gamut, and to enable the pixel using the sky blue to reproduce the color of the pixel using the deep blue. This will be described with reference to FIG. 8 further.

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

Referring to FIG. 8, the signal processor 400 according to the embodiment of the present invention includes a converter 410, an inverse converter 420, a color gamut determination unit 430, a selector 440, It may include an output unit 450.

The RGB image data R_in, G_in, and B_in (hereinafter, referred to as RGB input image data for convenience of description) input to the signal processor 400 may be converted to the conversion unit 410 for data conversion. Is entered.

The RGB input image data R_in, G_in, and B_in may also be input to the selector 440 and the color gamut determination unit 430. The RGB input image data R_in, G_in, and B_in input to the selector 440 may be referred to as second RGB image data R_d, G_d, and B_d for convenience of description. The first RGB image data R_d, G_d, and B_d correspond to image data for driving the R, G, and Bd subpixels of the pixel P when deep blue is selected from the corresponding pixel P. FIG. do.

The converter 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, and Z. For example, the conversion unit 410 converts the RGB signal of the RGB color coordinate system into an XYZ signal of the XYZ color coordinate system.

As described above, in the conversion of the color coordinate system by the conversion unit 410, the data conversion, that is, the data mapping process, of the change unit 410 applies color coordinate conversion when deep blue is used. That is, when the RGB input image data R_in, G_in, and B_in are implemented as pixels P using deep blue, the RGB input image data R_in, G_in, and B_in are implemented using data mapping corresponding to the color reproduction characteristics of the pixels P driving the deep blue. -to-XYZ color coordinate conversion is performed. Such color coordinate conversion is, for example,

... 변환식 (1)

... Conversion Formula (1)

It can be carried out through the equation (1), such as. Here, Md corresponds to a conversion matrix for converting an RGB signal to an XYZ signal when using deep blue. In this case, for convenience of description, the RGB-to-XYZ color coordinate transformation when deep blue is used may be referred to as a deep blue based color coordinate transformation. Meanwhile, a look-up table (LUT) for deep blue-based color coordinate conversion is provided in the conversion unit 410, and XYZ image data mapping to RGB input image data R_in, G_in, and B_in may be automatically performed.

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

The inverse transform unit 420 outputs the converted RGB image data R_s, G_s, and B_s by performing color coordinate inverse transform on the input XYZ image data. For example, the inverse transform unit 420 converts the XYZ signal of the XYZ color coordinate system into an RGB signal of the RGB color coordinate system.

As described above, in converting the color coordinate system in the inverse transform unit 420, the data transformation process of the inverse transform unit 420 applies the color coordinate inverse transform when Sky Blue is used. That is, when the input XYZ image data is implemented as the pixel P using sky blue, XYZ-to-RGB through data mapping corresponding to the color reproduction characteristics of the pixel P driving the corresponding sky blue. Inverse color coordinate conversion is performed. Such color coordinate inverse transformation is, for example,

... 변환식 (2)

... Conversion Formula (2)

Such as, can be performed via the conversion formula (2). Here, Ms corresponds to a conversion matrix for converting an RGB signal to an XYZ signal when Sky Blue is used. Therefore, Ms ^-1 corresponds to an inverse transformation matrix for inversely converting an XYZ signal to an RGB signal when using sky blue. Here, for convenience of description, the XYZ-to-RGB color coordinate inverse transform when using sky blue may be referred to as a sky blue based color coordinate inverse transform. On the other hand, a look-up table (LUT) for the sky blue-based color coordinate inverse transform is provided in the inverse transform unit 420, and the mapping of the RGB image data (R_s, G_s, B_s) to the input XYZ image data may be automatically performed. .

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. The first RGB image data R_s, G_s, and B_s may be configured to drive the R, G, and Bs subpixels of the pixel P when the sky blue is selected for the corresponding pixel P. Corresponds to video data.

As described above, the deep RGB based color coordinate transformation is performed on the RGB input image data R_in, G_in, and B_in, and thereafter, the sky blue based color coordinate inverse transformation is performed to perform the first RGB image data when sky blue is selected. (R_s, G_s, B_s) can be generated.

Accordingly, the first RGB image data R_s, G_s, and B_s for sky blue use may have the same XYZ color coordinate value as the second RGB image data R_d, G_d, and B_d for deep blue use. This means that for the same RGB input image data R_s, G_s, and B_s, the same color and luminance can be realized when using SkyBlue and Deep Blue. That is, the pixel P using sky blue may perform color reproduction like the pixel P using deep blue. As a result, although sky blue and deep blue are selected and used in two neighboring areas, the boundary phenomenon occurring in the right image of FIG. 7 may be improved.

On the other hand, the selection unit 440, the RGB input image data (R_in, G_in, B_in), that is, the second RGB image data (R_d, G_d, B_d), and the first RGB image data (R_s) output from the inverse converter 420 , G_s, B_s) will be input. For 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 input as described above, the selector 440 responds to the determination result of the color gamut determination unit 430. Then, one of the two input RGB image data is selected.

In this regard, the color gamut determination unit 430 determines whether the RGB input image data R_in, G_in, and B_in belong to the sky blue color gamut C1, that is, the first color gamut C1 shown in FIG. Otherwise, it is determined whether the color belongs to the color gamut C2, that is, the second color gamut C2, in which only the deep blow is expressed.

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

On the other hand, if it is determined that the color gamut determination unit 430 belongs to the second color gamut C2, the corresponding selection signal is output. In response to the selection signal, the selection unit 440 selects and outputs the second RGB image data R_d, G_d, and B_d.

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

Meanwhile, as described above, the color gamut determination unit 430 receives the RGB input image data R_in, G_in, and B_in to perform color gamut determination. On the other hand, the color gamut determination unit 430 may receive the XYZ image data output from the converter 410 and perform color gamut determination.

In performing the color gamut determination by the color gamut determination unit 430, for example, x and y color coordinate values are extracted from the input RGB input image data (R_in, G_in, B_in) or XYZ image data, and extracted. It is possible to determine whether x, y color coordinate values belong to the first color gamut C1 or the second color gamut C2.

The output unit 450 may add 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 subpixel among the Bs and Bc subpixels of the corresponding pixel P It is selected and driven. Accordingly, a value for non-emitting the Bd subpixel that has not been selected, for example, image data having a default value, should be allocated for the Bd subpixel. Therefore, in such a case, the output unit 450 outputs the input RGB image data R_out, G_out, and B_out as RGB image data R_out, G_out, and Bs_out, and the Bd image data having the default value (R_out, G_out, B_out). Bd_out) can be added.

On the other hand, unlike the above, 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 Bd part of the Bs and Bd subpixels of the corresponding pixel P is included. The pixel is selected and driven. Accordingly, a value for non-emitting the Bs subpixel that has not been selected, for example, image data having a default value, should be allocated for the Bs subpixel. Therefore, in such a case, the output unit 450 outputs the input RGB image data R_out, G_out, B_out as RGBd image data R_out, G_out, Bd_out, and the Bs image data having a default value ( Bs_out) can be added.

Meanwhile, the function of the output unit 450 as described above, that is, the function of outputting the Bs image data Bs_out or Bd image data Bd_out having a default value in addition to the input image data R_out, G_out, B_out, is output. It may be configured in the selector 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 image data R_d, G_d, and B_d are selected, the selection unit 440 may output Bs image data having a default value.

FIG. 9 is a picture 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 this case, looking at the image on the left side, it can be seen that the boundary phenomenon occurs in the sky background of the upper side, similar to FIG. That is, it can be seen that a boundary occurs between the area where the sky blue is used and the area where the deep part is used.

On the other hand, looking at the image on the right, it can be seen that the boundary phenomenon in the image on the left is resolved. As described above, this is an effect of adjusting RGB input image data so that pixels in an area where sky blue is used can perform color reproduction similar to pixels in an area where deep blue is used.

Embodiment of the present invention described above is an example of the present invention, it is possible to change freely within the scope included in the spirit of the present invention. Accordingly, the invention includes modifications of the invention within the scope of the appended claims and their equivalents.

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

2 is an equivalent circuit diagram of a subpixel according to an embodiment of the present invention.

3 to 5 illustrate examples of an arrangement structure of subpixels constituting a pixel according to an exemplary embodiment of the present invention.

6 shows a CIE 1931 color coordinate system.

7 is a photograph showing an image to be represented by the input RGB image data and the image represented by the RGBsBd image data.

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

9 is a picture 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.

Description of the Related Art

400: signal processor 410: converter

420: inverse transform unit 430: color gamut determination unit

440: selection unit 450: output unit

Claims (8)

An organic light emitting panel including a pixel including R (red), G (green), Bs (sky blue), and Bd (deep blue) subpixels; When the R, G, and B input image data corresponding to the pixel belong to the first color gamut, the first R, G, and B image data are output, and when the R, G, and B input image data belong to the second color gamut, A signal processor for outputting second R, G, and B image data which are input image data, The first R, G, and B image data respectively correspond to the R, G, and Bs subpixels, and the second R, G, and B image data respectively correspond to the R, G, and Bd subpixels, The signal processor may perform deep blue based color coordinate transformation on the R, G, and B input image data to generate X, Y, and Z image data, and perform sky blue based color coordinate inverse transformation on the X, Y, and Z image data. To generate the first R, G, and B image data, The first color gamut corresponds to a sky blue color gamut, The second color gamut corresponds to an area other than the sky blue color gamut in the deep blue gamut. Organic light emitting display device. The method of claim 1, The signal processing unit, A conversion unit for generating X, Y, and Z image data by performing deep blue-based color coordinate transformation on the R, G, and B input image data; An inverse transform unit generating first R, G, and B image data by performing sky blue-based color coordinate inverse transform on the X, Y, and Z image data; A color gamut determination unit configured to determine which of the first and second color gamuts belong to the R, G, and B input image data; And a selection unit 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 light emitting display device. The method of claim 1, The signal processing unit, In the case of outputting the first R, G and B image data, the first R, G and B image data and the image data for non-emitting the Bd subpixel are output together. In the case of outputting the second R, G, and B image data, the second R, G, and B image data and the image data for non-emitting the Bs subpixel are output together. Organic light emitting display device. The method of claim 1, The R, G, Bs, and Bd subpixels constituting the pixel are arranged in a stripe type or quad type structure. In the driving method of an organic light emitting display device comprising a pixel composed of R (red), G (green), Bs (sky blue), Bd (deep blue) subpixels, Outputting first R, G, and B image data by the signal processor when the R, G, and B input image data corresponding to the pixel belong to the first color gamut; If the R, G, B input image data belongs to a second color gamut, outputting, by the signal processor, second R, G, B image data, which is the R, G, B input image data; , The first R, G, and B image data respectively correspond to the R, G, and Bs subpixels, and the second R, G, and B image data respectively correspond to the R, G, and Bd subpixels, 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 transformation on the R, G, and B input image data. Become, The first color gamut corresponds to a sky blue color gamut, The second color gamut corresponds to an area other than the sky blue color gamut in the deep blue gamut. A method of driving an organic light emitting display device. 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 selector of the signal processor; Determining, by the color gamut determination unit of the signal processing unit, which of the first and second color gamuts belong to the R, G, and B input image data; Selecting, by the selector, 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; The organic light emitting display device driving method further comprising. The method of claim 5, Outputting the first R, G, and B image data together with the image data to non-emit the Bd subpixel when the signal processing unit outputs the first R, G, and B image data; ; When the signal processor outputs the second R, G, and B image data, outputting the second R, G, and B image data together with the image data to non-emit the Bs subpixel. The organic light emitting display device driving method further comprising. The method of claim 5, And the R, G, Bs, and Bd subpixels constituting the pixel are arranged in a stripe type or quad type structure.

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