Patent Publication Number: US-2022215786-A1

Title: Display device and driving method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a continuation application of U.S. patent application Ser. No. 16/732,744 filed on Jan. 2, 2020, which claims priority under 35 U.S.C. § 119(a) to Korean patent application no. 10-2019-0024131, filed on Feb. 28, 2019 in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     Exemplary embodiments of the inventive concept relate to a display device and a driving method thereof. 
     DISCUSSION OF RELATED ART 
     With the development of information technologies, the importance of a display device as a connection medium between a user and information increases. Accordingly, display devices such as liquid crystal display devices, organic light emitting display devices, and plasma display devices are increasingly used. 
     An organic light emitting display device includes a plurality of pixels, and allows organic light emitting diodes of the plurality of pixels to emit lights to correspond to a plurality of grayscale values constituting an image frame, thus displaying the image frame. 
     In general, in the organic light emitting display device, grayscale voltages are set to exhibit a luminance according to a gamma curve preferred by white color light emitted when pixels of different colors emit lights with the same luminance. 
     Therefore, when mixed color light or single color light instead of the white color light is emitted using the set grayscale voltages, the luminance of the mixed color light or single color light does not accurately correspond to the above-described gamma curve. In addition, lateral leakage may occur where, when the single color light is emitted, holes of driving current flowing through a corresponding pixel are leaked to adjacent pixels having small resistance through a P-doped Hole Injection Layer (PHIL) that is a layer shared by the organic light emitting diodes. Therefore, light may not be emitted with a desired luminance. 
     SUMMARY 
     According to an exemplary embodiment of the inventive concept, a display device may include a processor, and a display panel configured to receive observation grayscale values from the processor. The display panel includes a data driver configured to apply data voltages to data lines, a target pixel coupled to at least one of the data lines, and observation pixels each coupled to at least one of the data lines, and located adjacent to the target pixel. The display panel applies a first data voltage to the target pixel, when the observation grayscale values for the observation pixels exceed a reference value, the display panel applies a second data voltage to the target pixel, when at least one of the observation grayscale values does not exceed the reference value, and the first data voltage and the second data voltage are different from each other. 
     No other pixels may exist between the target pixel and the observation pixels. 
     The target pixel may emit light of a first color. Some of the observation pixels may emit light of a second color different from the first color, and the others of the observation pixels may emit light of a third color different from the first color and the second color. 
     When a driving transistor of the target pixel is a P-type transistor, the first data voltage may be larger than the second data voltage. 
     When a driving transistor of the target pixel is an N-type transistor, the first data voltage may be smaller than the second data voltage. 
     According to an exemplary embodiment of the inventive concept, a display device may include a target pixel emitting light of a first color, second color observation pixels located adjacent to the target pixel, and emitting light of a second color different from the first color, third color observation pixels located adjacent to the target pixel, and emitting light of a third color different from the first color and the second color, and a grayscale corrector configured to convert an input grayscale value corresponding to the target pixel, with reference to second color observation grayscale values corresponding to the second color observation pixels and third color observation grayscale values corresponding to the third color observation pixels. The grayscale corrector includes a light emitting pixel counter configured to provide a second color light emitting pixel number by counting a number of the second color observation grayscale values that exceed a reference value, and provide a third color light emitting pixel number by counting a number of the third color observation grayscale values that exceed the reference value, and a grayscale converter configured to provide a converted grayscale value obtained by converting the input grayscale value, based on the second color light emitting pixel number and the third color light emitting pixel number. 
     The grayscale corrector may further include a single color offset provider configured to provide single color offset values. When the second color light emitting pixel number is 0 and the third color light emitting pixel number is 0, the grayscale converter may generate the converted grayscale value by adding a corresponding offset value among the single color offset values to the input grayscale value. 
     The grayscale corrector may further include a double mixed color offset provider configured to provide double mixed color offset values. When the second color light emitting pixel number is greater than 0 and the third color light emitting pixel number is 0, the grayscale converter may generate the converted grayscale value by adding a corresponding offset value among the double mixed color offset values to the input grayscale value. 
     The grayscale corrector may further include a triple mixed color offset provider configured to provide triple mixed color offset values. When the second color light emitting pixel number is greater than 0, the third color light emitting pixel number is greater than 0, and the second color light emitting pixel number and the third color light emitting pixel number are not respectively equal to a number of the second color observation pixels and a number of the third color observation pixels, the grayscale converter may generate the converted grayscale value by adding a corresponding offset value among the triple mixed color offset values to the input grayscale value. 
     The grayscale converter may determine the input grayscale value as the converted grayscale value, when the second color light emitting pixel number is equal to the number of the second color observation pixels and the third color light emitting pixel number is equal to the number of the third color observation pixels. 
     The single color offset provider may include a single color reference offset provider configured to receive an input maximum luminance value, and provide reference offset values corresponding to the input maximum luminance value, and a single color total offset generator configured to generate the single color offset values by interpolating the reference offset values. 
     The single color reference offset provider may include a single color preset determiner configured to pre-store preset offset values corresponding to preset maximum luminance values, and determine whether the input maximum luminance value corresponds to any one of the preset maximum luminance values. When the input maximum luminance value corresponds to any one of the preset maximum luminance values, the single color preset determiner may provide the corresponding preset offset values as the reference offset values. 
     When the input maximum luminance value does not correspond to any one of the preset maximum luminance values, the single color preset determiner may provide the preset offset values corresponding to at least two preset maximum luminance values, and the single color reference offset provider may further include a single reference offset generator configured to generate the reference offset values by interpolating the preset offset values corresponding to the at least two preset maximum luminance values. 
     The preset maximum luminance values may include a maximum value and a minimum value of the receivable input maximum luminance value. 
     The preset maximum luminance values may further include a first intermediate maximum luminance value, and when the input maximum luminance value is a value between the maximum value and the first intermediate maximum luminance value, a grayscale voltage corresponding to the converted grayscale value may be adjusted corresponding to the input maximum luminance value. 
     When the input maximum luminance value is a value between the minimum value and the first intermediate maximum luminance value, an emission period of the target pixel may be adjusted corresponding to the input maximum luminance value. 
     The preset maximum luminance values may further include a second intermediate maximum luminance value that is a value between the first intermediate maximum luminance value and the minimum value. 
     According to an exemplary embodiment of the inventive concept, for a method for driving a display device, the display device may include a target pixel configured to emit light of a first color, second color observation pixels located adjacent to the target pixel, and configured to emit light of a second color different from the first color, and third color observation pixels located adjacent to the target pixel, and configured to emit light of a third color different from the first color and the second color. The driving method may include receiving an input grayscale value corresponding to the target pixel, second color observation grayscale values corresponding to the second color observation pixels, and third color observation grayscale values corresponding to the third color observation pixels, determining a second color light emitting pixel number by counting a number of the second color observation grayscale values that exceed a reference value, determining a third color light emitting pixel number by counting a number of the third color observation grayscale values that exceed the reference value, and generating a converted grayscale value by converting the input grayscale value, based on the second color light emitting pixel number and the third color light emitting pixel number. 
     In the generating of the converted grayscale value, the converted grayscale value may be generated by adding a single color offset value to the input grayscale value, when the second color light emitting pixel number is 0 and the third color light emitting pixel number is 0. 
     In the generating of the converted grayscale value, the converted grayscale value may be generated by adding a double mixed color offset value to the input grayscale value, when the second color light emitting pixel number is greater than 0 and the third color light emitting pixel number is 0. 
     In the generating of the converted grayscale value, the converted grayscale value may be generated by adding a triple mixed color offset value to the input grayscale value, when the second color light emitting pixel number is greater than 0, the third color light emitting pixel number is greater than 0, and the second color light emitting pixel number and the third color light emitting pixel number are not respectively equal to a number of the second color observation pixels and a number of the third color observation pixels. 
     In the generating of the converted grayscale value, the input grayscale value may be determined as the converted grayscale value, when the second color light emitting pixel number is equal to the number of the second color observation pixels, and the third color light emitting pixel number is equal to the number of the third color observation pixels. 
     The display panel may be further configured to receive an input grayscale value from the processor, and the display panel may apply the first data voltage and the second data voltage when the input grayscale value for the target pixel exceeds the reference value. 
     According to an exemplary embodiment of the inventive concept, a display panel may include a target pixel connected to a first scan line and a first data line, and configured to emit light of a first color, second color observation pixels located adjacent to the target pixel, connected to scan lines adjacent to the first scan line, and configured to emit light of a second color different from the first color, third color observation pixels located adjacent to the target pixel, connected to the first scan line or the first data line, and configured to emit light of a third color different from the first color and the second color, and a grayscale corrector configured to convert an input grayscale value corresponding to the target pixel to a converted grayscale value, based on whether the second color observation pixels and the third color observation pixels are in an emission state. A pixel is in the emission state when a corresponding grayscale value exceeds a reference value. 
     No other pixels may exist between the target pixel and the second color observation pixels and between the target pixel and the third color observation pixels. 
     A second color light emitting pixel number may be a number of the second color observation pixels in the emission state, a third color light emitting pixel number may be a number of the third color observation pixels in the emission state, and the converted grayscale value may be generated based on the second color light emitting pixel number and the third color light emitting pixel number. 
     The input grayscale value may be determined as the converted grayscale value, when the second color light emitting pixel number is equal to the total number of the second color observation pixels, and the third color light emitting pixel number is equal to the total number of the third color observation pixels. 
     The input grayscale value added with an offset value may be determined as the converted grayscale value, when the second color light emitting pixel number is not equal to the total number of the second color observation pixels, or the third color light emitting pixel number is not equal to the total number of the third color observation pixels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the inventive concept will be more clearly understood by describing in detail exemplary embodiments thereof with reference to the accompanying drawings. 
         FIG. 1  is a diagram illustrating a display device in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 2  is a diagram illustrating a pixel of the display device shown in  FIG. 1  in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 3  is a diagram illustrating a driving method of the pixel shown in  FIG. 2  in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 4  is a diagram illustrating a display device in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 5  is a diagram illustrating a pixel of the display device shown in  FIG. 4  in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 6  is a diagram illustrating a driving method of the pixel shown in  FIG. 5  in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 7  is a diagram illustrating a grayscale voltage generator in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 8  is a diagram illustrating a portion of the grayscale voltage generator shown in  FIG. 7  in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 9 and 10  are diagrams illustrating a case where pixels emit white color light according to a maximum luminance value in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 11  is a diagram illustrating a white color light curve and single color light curves at an arbitrary maximum luminance value in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 12 to 26  are diagrams illustrating observation pixels according to a color of a target pixel, a unit area, a single color, a double mixed color, a triple mixed color, and a white color in accordance with exemplary embodiments of the inventive concept. 
         FIG. 27  is a diagram illustrating a grayscale corrector in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 28 to 30  are diagrams illustrating a single color offset provider in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 31  is a diagram illustrating a configuration of an offset value in accordance with an exemplary embodiment of the inventive concept. 
         FIG. 32  is a diagram illustrating an effect obtained by applying a single color offset value in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 33 and 34  are diagrams illustrating a single color reference offset provider in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 35 to 38  are diagrams illustrating a first double mixed color offset provider and a first triple mixed color offset provider in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 39 to 42  are diagrams illustrating a second double mixed color offset provider and a second triple mixed color offset provider in accordance with an exemplary embodiment of the inventive concept. 
         FIGS. 43 to 46  are diagrams illustrating a third double mixed color offset provider and a third triple mixed color offset provider in accordance with an exemplary embodiment of the inventive concept. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Exemplary embodiments of the inventive concept provide a display device capable of exhibiting a desired luminance even when single color light and mixed color light are emitted in addition to white color light, and a driving method of the display device. 
     Exemplary embodiments of the inventive concept will be described more fully hereinafter with reference to the accompanying drawings. Like reference numerals may refer to like elements throughout this application. 
       FIG. 1  is a diagram illustrating a display device in accordance with an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 1 , the display device in accordance with an exemplary embodiment of the inventive concept may include a processor  9  and a display panel  10 . For example, the display panel  10  may include a timing controller  11 , a data driver  12 , a scan driver  13 , a pixel unit  14 , a grayscale voltage generator  15 , and a grayscale corrector  16 . 
     The processor  9  may provide grayscale values and control signals with respect to an image frame. The processor  9  may be an application processor, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), etc. The processor  9  may provide grayscale values to be matched to a structure (e.g., a pentile structure or an RGB stripe structure) of the pixel unit  14 . For example, the processor  9  may provide grayscales to correspond one-to-one to pixels RPij included in the pixel unit  14 . The processor  9  may also provide grayscale values regardless of the structure of the pixel unit  14 . The processor  9  may provide a red grayscale value, a green grayscale value, and a blue grayscale value with respect to one dot. A number of the grayscale values may be different from that of the pixels included in the pixel unit  14 . 
     The timing controller  11  may receive grayscale values and control signals with respect to an image frame from the processor  9 . When the processor  9  provides grayscale values to be matched to the structure of the pixel unit  14 , the timing controller  11  may provide the received grayscale values to the grayscale corrector  16 . When the processor  9  provides grayscale values regardless of the structure of the pixel unit  14 , the timing controller  11  may generate grayscale values rendered to correspond one-to-one to the pixels included in the pixel unit  14  by rendering the received grayscale values, and provide the rendered grayscale values to the grayscale corrector  16 . 
     The grayscale corrector  16  may provide converted grayscale values by correcting grayscale values. 
     The timing controller  11  may provide such converted grayscale values and control signals to the data driver  12 . Additionally, the timing controller  11  may provide a clock signal, a scan start signal, etc. to the scan driver  13 . 
     The data driver  12  may generate data voltages to be provided to data lines DL 1 , DL 2 , DL 3 , . . . , and DLn by using the converted grayscale values and the control signals, which are received from the timing controller  11 . For example, the data driver  12  may sample the converted grayscale values by using a clock signal, and apply data voltages corresponding to the converted grayscale values to the data lines DL 1  to DLn in units of pixel rows. Here, n may be an integer greater than 0. The data voltages may correspond to grayscale voltages RV 0  to RV 255 , GV 0  to GV 255 , and BV 0  to BV 255  provided from the grayscale voltage generator  15 . 
     In other words, different data voltages may be generated based on the converted grayscale values. The grayscale values for pixels may be compared to a reference value to determine an emission state of the pixels. Different grayscale values result in different converted grayscale values. As such, for example, a first data voltage may be generated and applied to a target pixel, when an input grayscale value for the target pixel exceeds the reference value and the grayscale values for observation pixels adjacent to the target pixel exceed the reference value. A second data voltage different from the first data voltage may be generated and applied to the target pixel, when the input grayscale value exceeds the reference value and at least one of the grayscale values for the observation pixels does not exceed the reference value. This will be described in further detail below with reference to  FIGS. 12 to 46 . 
     The scan driver  13  may generate scan signals to be provided to scan lines SL 1 , SL 2 , SL 3 , . . . , and SLm by receiving the clock signal, the scan start signal, etc. from the timing controller  11 . For example, the scan driver  13  may sequentially provide scan signals having a pulse of a turn-on level to the scan lines SL 1  to SLm. For example, the scan driver  13  may be configured in a shift register form, and generate scan signals in a manner that sequentially transfers the scan start signal in the form of a pulse of a turn-on level to a next scan stage circuit in response to the clock signal. Here, p may be an integer that is not 0. Here, m may be an integer greater than 0. 
     The pixel unit  14  includes pixels. Each pixel RPij may be coupled to a corresponding data line and a corresponding scan line. Here, i and j may be integers greater than 0. The pixel RPij may refer to a pixel coupled to an ith scan line and a jth data line. 
     The pixel unit  14  may include pixels emitting light of a first color, pixels emitting light of a second color, and pixels emitting light of a third color. The first color, the second color, and the third color may be colors different from one another. For example, the first color may be one color among red, green, and blue colors, the second color may be another color different from the first color among the red, green, and blue colors, and the third color may be another color different from the first color and the second color among the red, green, and blue colors. In addition, magenta, cyan, and yellow colors may be used instead of the red, green, and blue colors as the first to third colors. However, for convenience of description, a case is described where the red, green, and blue colors are used as the first to third colors, the magenta color is expressed as a combination of the red and blue colors, the cyan color is expressed as a combination of the green and blue colors, and the yellow color is expressed as a combination of the red and green colors. 
     Hereinafter, a case where the pixel unit  14  is disposed in a diamond pentile structure is assumed and described. However, even if the pixel unit  14  is disposed in another structure, e.g., an RGB-stripe structure, an S-stripe structure, a real RGB structure, a normal pentile structure, etc., those skilled in the art may implement the inventive concept by appropriately setting a target pixel and observation pixels, which will be described later. 
     Hereinafter, the position of the pixel RPij is described with respect to the position of each light emitting diode (particularly, an emitting layer). The position of a pixel circuit coupled to each light emitting diode may not correspond to that of the light emitting diode, and the pixel circuit and the light emitting diode may be appropriately disposed so as to achieve space efficiency. 
     The grayscale voltage generator  15  may receive an input maximum luminance value DBVI, and provide the grayscale voltages RV 0  to RV 255  with respect to the pixels of the first color, the grayscale voltages GV 0  to GV 255  with respect to the pixels of the second color, and the grayscale voltages BV 0  to BV 255  with respect to the pixels of the third color, which correspond to the input maximum luminance value DBVI. Hereinafter, for convenience of description, a case is described where a total of 256 grayscales from grayscale 0 (minimum grayscale) to grayscale 255 (maximum grayscale) exist. However, when a grayscale value is expressed with eight bits or more, a larger number of grayscales may exist. 
     A maximum luminance value may be a luminance value of light emitted from pixels, corresponding to the maximum grayscale. For example, the maximum luminance value may be a luminance value of white color light generated when a pixel of the first color emits light corresponding to the grayscale 255, a pixel of the second color emits light corresponding to the grayscale 255, and a pixel of the third color emits light corresponding to the grayscale 255. The pixel of the first color, the pixel of the second color, and the pixel of the third color constitute one dot. The unit of the luminance value may be nit. 
     Therefore, the pixel unit  14  may display a partially (spatially) dark or bright image frame, but the maximum brightness of the image frame is limited to the maximum luminance value. Such a maximum luminance value may be manually set by manipulation of a user with respect to the display panel  10 , or be automatically set by an algorithm associated with an illumination sensor, etc. The set maximum luminance value is expressed as an input maximum luminance value. 
     The maximum luminance value may vary depending on products. However, for example, the maximum value of the maximum luminance value may be 1200 nits, and the minimum value of the maximum luminance value may be 4 nits. When the input maximum luminance value DBVI varies with respect to the same grayscale value, the grayscale voltage generator  15  provides other grayscale values RV 0  to RV 255 , GV 0  to GV 255 , and BV 0  to BV 255 , and therefore, the light emitting luminance of the pixel varies. 
     The grayscale corrector  16  may correct an input grayscale value to a converted grayscale value as described above. The grayscale corrector  16  will be described in detail with reference to  FIG. 15 . 
     In the above-described exemplary embodiment, a case where the grayscale corrector  16  is a component separate from the timing controller  11  is illustrated. However, in exemplary embodiments of the inventive concept, a portion or the whole of the grayscale corrector  16  may be integrally configured with the timing controller  11 . For example, a portion or the whole of the grayscale corrector  16  may be configured together with the timing controller  11  in an integrated circuit form. In exemplary embodiments of the inventive concept, a portion or the whole of the grayscale corrector  16  may be implemented in a software manner in the timing controller  11 . 
     In an exemplary embodiment of the inventive concept, a portion or the whole of the grayscale corrector  16  may be configured together with the data driver  12  in an integrated circuit form. In exemplary embodiments of the inventive concept, a portion or the whole of the grayscale corrector  16  may be implemented in a software manner in the data driver  12 . Therefore, the timing controller  11  may provide input grayscale values to the data driver  12 , and the grayscale corrector  16  or the data driver  12  may autonomously correct the input grayscale values to converted grayscale values. 
     In an exemplary embodiment of the inventive concept, a portion or the whole of the grayscale corrector  16  may be configured together with the processor  9  in an integrated circuit form. In an exemplary embodiment of the inventive concept, a portion or the whole of the grayscale corrector  16  may be implemented in a software manner in the processor  9 . Therefore, the timing controller  11  may directly receive converted grayscale values from the processor  9 . 
       FIG. 2  is a diagram illustrating a pixel of the display device shown in  FIG. 1  according to an exemplary embodiment of the inventive concept.  FIG. 3  is a diagram illustrating a driving method of the pixel shown in  FIG. 2  according to an exemplary embodiment of the inventive concept. 
     The pixel RPij may be a pixel emitting light of the first color. Pixels emitting light of the second color or the third color include components substantially identical to those of the pixel RPij except a light emitting diode R_LD 1 , and therefore, overlapping descriptions will be omitted. 
     The pixel RPij may include a plurality of transistors T 1 , and T 2 , a storage capacitor Cst 1 , and the light emitting diode R_LD 1 . 
     Although a case where the transistors are implemented with a P-type transistor, e.g., a PMOS transistor, is illustrated in the present exemplary embodiment, those skilled in the art may implement a pixel circuit that performs substantially the same function, using an NMOS transistor. 
     A gate electrode of the transistor T 2  is coupled to a scan line SLi, one electrode of the transistor T 2  is coupled to a data line DLj, and the other electrode of the transistor T 2  is coupled to a gate electrode of the transistor T 1 . The transistor T 2  may be referred to as a scan transistor, a switching transistor, etc. 
     The gate electrode of the transistor T 1  is coupled to the other electrode of the transistor T 2 , one electrode of the transistor T 1  is coupled to a first power line ELVDD, and the other electrode of the transistor T 1  is coupled to an anode of the light emitting diode R_LD 1 . The transistor T 1  may be referred to as a driving transistor. 
     The storage capacitor Cst 1  couples the one electrode and the gate electrode of the transistor T 1  to each other. 
     The anode of the light emitting diode R_LD 1  is coupled to the other electrode of the transistor T 1 , and a cathode of the light emitting diode R_LD 1  is coupled to a second power line ELVSS. The light emitting diode R_LD 1  may be a device emitting light having a wavelength corresponding to the first color. The light emitting diode R_LD 1  may be implemented with an organic light emitting diode, an inorganic light emitting diode, a quantum dot light emitting diode, etc. The pixel RPij shown in  FIG. 2  includes a single light emitting diode R_LD 1 . However, in an exemplary embodiment of the inventive concept, the pixel RPij may include a plurality of light emitting diodes. The plurality of light emitting diodes may be coupled in parallel with the same polarity, or be coupled in parallel with different polarities. 
     When a scan signal of a turn-on level (low level) is supplied to the gate electrode of the transistor T 2  through the scan line SLi, the transistor T 2  couples the data line DLj and one electrode of the storage capacitor Cst 1  to each other. Therefore, a voltage value according to the difference between a data voltage DATAij applied through the data line DLj and a first power voltage is stored in the storage capacitor Cst 1 . The data voltage DATAij may correspond to one of the grayscale voltages RV 0  to RV 255 . 
     The transistor T 1  allows a driving current determined according to the voltage stored in the storage capacitor Cst 1  to flow from the first power line ELVDD to the second power line ELVSS. The light emitting diode R_LD 1  emits light with a luminance corresponding to an amount of the driving current. 
       FIG. 4  is a diagram illustrating a display device in accordance with an exemplary embodiment of the inventive concept. 
     A display panel  10 ′ shown in  FIG. 4  may include a configuration substantially identical to the display panel  10  shown in  FIG. 1 , except for an emission driver  17  and a pixel unit  14 ′. Therefore, overlapping descriptions will be omitted. 
     The emission driver  17  may generate emission signals to be provided to emission lines EL 1 , EL 2 , EL 3 , . . . , and ELo by receiving a clock signal, an emission stop signal, etc. from the timing controller  11 . For example, the emission driver  17  may sequentially provide emission signals having a pulse of a turn-off level to the emission lines EL 1  to ELo. For example, the emission driver  17  may be configured in a shift register form, and generate emission signals in a manner that sequentially transfers the emission stop signal in the form of a pulse of a turn-off level to a next scan stage circuit in response to the clock signal. Here, o may be a natural number. 
     The pixel unit  14 ′ may include pixels. Each pixel RPij′ may be coupled to a corresponding data line, a corresponding scan line, and a corresponding emission line. 
       FIG. 5  is a diagram illustrating a pixel of the display device shown in  FIG. 4  according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 4 , the pixel RPij′ may include transistors M 1 , M 2 , M 3 , M 4 , M 5 , M 6 , and M 7 , a storage capacitor Cst 2 , and a light emitting diode R_LD 2 . 
     One electrode of the storage capacitor Cst 2  is coupled to the first power line ELVDD, and the other electrode of the storage capacitor Cst 2  is coupled to a gate electrode of the transistor M 1 . 
     One electrode of the transistor M 1  is coupled to the other electrode of the transistor M 5 , the other electrode of the transistor M 1  is coupled to one electrode of the transistor M 6 , and the gate electrode of the transistor M 1  is coupled to the other electrode of the storage capacitor Cst 2 . The transistor M 1  may be referred to as a driving transistor. The transistor M 1  determines an amount of driving current flowing between the first power line ELVDD and the second power line ELVSS according to a potential difference between the gate electrode and a source electrode thereof. 
     One electrode of the transistor M 2  is coupled to the data line DLj, the other electrode of the transistor M 2  is coupled to the one electrode of the transistor M 1 , and a gate electrode of the transistor M 2  is coupled to a current scan line SLi. The transistor M 2  may be referred to as a switching transistor, a scan transistor, etc. When a scan signal of a turn-on level is applied to the current scan line SLi, the transistor M 2  allows a data voltage of the data line DLj to be input to the pixel RPij′. 
     One electrode of the transistor M 3  is coupled to the other electrode of the transistor M 1 , the other electrode of the transistor M 3  is coupled to the gate electrode of the transistor M 1 , and a gate electrode of the transistor M 3  is coupled to the current scan line SLi. When a scan signal of a turn-on level is applied to the current scan line SLi, the transistor M 3  allows the transistor M 1  to be diode-coupled. 
     One electrode of the transistor M 4  is coupled to the gate electrode of the transistor M 1 , the other electrode of the transistor M 4  is coupled to an initialization voltage line VINT, and a gate electrode of the transistor M 4  is coupled to a previous scan line SL(i−1). In an exemplary embodiment of the inventive concept, the gate electrode of the transistor M 4  may be coupled to another scan line. When a scan signal of a turn-on level is applied to the previous scan line SL(i−1), the transistor M 4  initializes a quantity of electric charges of the gate electrode of the transistor M 1  by transferring an initialization voltage to the gate electrode of the transistor M 1 . 
     One electrode of the transistor M 5  is coupled to the first power line ELVDD, the other electrode of the transistor M 5  is coupled to the one electrode of the transistor M 1 , and a gate electrode of the transistor M 5  is coupled to an emission line ELi. The one electrode of the transistor M 6  is coupled to the other electrode of the transistor M 1 , the other electrode of the transistor M 6  is coupled to an anode of the light emitting diode R_LD 2 , and a gate electrode of the transistor M 6  is coupled to the emission line ELi. The transistors M 5  and M 6  may be referred to as emission transistors. When an emission signal of a turn-on level is applied to the emission line ELi, the transistors M 5  and M 6  allow the light emitting diode R_LD 2  to emit light by forming a driving current path between the first power line ELVDD and the second power line ELVSS. 
     One electrode of the transistor M 7  is coupled to the anode of the light emitting diode R_LD 2 , the other electrode of the transistor M 7  is coupled to the initialization voltage line VINT, and a gate electrode of the transistor M 7  is coupled to the current scan line SLi. In an exemplary embodiment of the inventive concept, the gate electrode of the transistor M 7  may be coupled to another scan line. For example, the gate electrode of the transistor M 7  may be coupled to the previous scan line SL(i−1) or a previous scan line prior to the previous scan line SL(i−1), or a next scan line SL(i+1) or a next scan line posterior to the next scan line SL(i+1). When a scan signal of a turn-on level is applied to the current scan line SLi, the transistor M 7  initializes a quantity of electric charges accumulated in the light emitting diode R_LD 2  by transferring an initialization voltage to the anode of the light emitting diode R_LD 2 . 
     The anode of the light emitting diode R_LD 2  is coupled to the other electrode of the transistor M 6 , and a cathode of the light emitting diode R_LD 2  is coupled to the second power line ELVSS. The light emitting diode R_LD 2  may be implemented with an organic light emitting diode, an inorganic light emitting diode, a quantum dot light emitting diode, etc. The pixel RPij′ shown in  FIG. 5  includes a single light emitting diode R_LD 2 . However, in an exemplary embodiment of the inventive concept, the pixel RPij′ may include a plurality of light emitting diodes. The plurality of light emitting diodes may be coupled in parallel with the same polarity, or be coupled in parallel with different polarities. 
       FIG. 6  is a diagram illustrating a driving method of the pixel shown in  FIG. 5  according to an exemplary embodiment of the inventive concept. 
     First, a scan signal of a turn-on level (low level) is applied to the previous scan line SL(i−1). Since the transistor M 4  is in a turn-on state, an initialization voltage is applied to the gate electrode of the transistor M 1  such that the quantity of electric charges is initialized. Since an emission signal of a turn-off level is applied to the emission line ELi, the transistors M 5  and M 6  are in a turn-off state, and unnecessary emission of the light emitting diode R_LD 2  in the process of applying the initialization voltage is prevented. 
     Next, a data voltage DATAij with respect to a current pixel row is applied to the data line DLj, and a scan signal of a turn-on level is applied to the current scan line SLi. Accordingly, the transistors M 2 , M 1 , and M 3  are in a conducting state, and the data line DLj and the gate electrode of the transistor M 1  are electrically coupled to each other. Thus, the data voltage DATAij is applied to the other electrode of the storage capacitor Cst 2 , and the storage capacitor Cst 2  accumulates a quantity of electric charges corresponding to the difference between a voltage of the first power line ELVDD and the data voltage DATAij. 
     Since the transistor M 7  is in the turn-on state, the anode of the light emitting diode R_LD 2  and the initialization voltage line VINT are coupled to each other, and a quantity of electric charges corresponding to the difference between the initialization voltage of the light emitting diode R_LD 2  and a voltage of the second power line ELVSS is precharged or initialized. 
     Subsequently, when an emission signal of a turn-on level is applied to the emission line ELi, the transistors M 5  and M 6  are in the conducting state, and an amount of driving current flowing through the transistor M 1  is controlled according to the quantity of electric charges accumulated in the storage capacitor Cst 2 , so that the driving current flows through the light emitting diode R_LD 2 . The light emitting diode R_LD 2  emits light until before an emission signal of a turn-off level is applied to the emission line ELi. 
       FIG. 7  is a diagram illustrating a grayscale voltage generator in accordance with an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 7 , the grayscale voltage generator  15  may include a first grayscale voltage generator  151 , a second grayscale voltage generator  152 , and a third grayscale voltage generator  153 . 
     The first grayscale voltage generator  151  may receive the input maximum luminance value DBVI, and provide the grayscale voltages RV 0  to RV 255  with respect to the pixels of the first color, which correspond to the input maximum luminance value DBVI. 
     The second grayscale voltage generator  152  may receive the input maximum luminance value DBVI, and provide the grayscale voltages GV 0  to GV 255  with respect to the pixels of the second color, which correspond to the input maximum luminance value DBVI. 
     The third grayscale voltage generator  153  may receive the input maximum luminance value DBVI, and provide the grayscale voltages BV 0  to BV 255  with respect to the pixels of the third color, which correspond to the input maximum luminance value DBVI. 
       FIG. 8  is a diagram illustrating a portion of the grayscale voltage generator shown in  FIG. 7  according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 8 , the first grayscale voltage generator  151  may include a selection value provider  1511 , a grayscale voltage output unit  1512 , resistor strings RS 1  to RS 11 , multiplexers MX 1  to MX 12 , and resistors R 1  to R 10 . 
     Each of the second grayscale voltage generator  152  and the third grayscale voltage generator  153  may include a configuration substantially identical to that of the first grayscale voltage generator  151 , and therefore, overlapping descriptions will be omitted. 
     The selection value provider  1511  may provide selection values with respect to the multiplexers MX 1  to MX 12  according to the input maximum luminance value DBVI. The selection values according to the input maximum luminance value DBVI may be pre-stored in a memory device, e.g., a device such as a register. 
     The resistor string RS 1  may generate intermediate voltages between a first reference voltage VH and a second reference voltage VL. The multiplexer M 1  may output a third reference voltage VT by selecting one of the intermediate voltages provided from the resistor string RS 1  according to a selection value. The multiplexer MX 2  may output a 255-grayscale voltage RV 255  by selecting one of the intermediate voltages provided from the resistor string RS 1  according to a selection value. 
     The resistor string RS 11  may generate intermediate voltages between the third reference voltage VT and the 255-grayscale voltage RV 255 . The multiplexer MX 12  may output a 203-grayscale voltage RV 203  by selecting one of the intermediate voltages provided from the resistor string RS 11  according to a selection value. 
     The resistor string RS 10  may generate intermediate voltages between the third reference voltage VT and the 203-grayscale voltage RV 203 . The multiplexer MX 11  may output a 151-grayscale voltage RV 151  by selecting one of the intermediate voltages provided from the resistor string RS 10  according to a selection value. 
     The resistor string RS 9  may generate intermediate voltages between the third reference voltage VT and the 151-grayscale voltage RV 151 . The multiplexer MX 10  may output an 87-grayscale voltage RV 87  by selecting one of the intermediate voltages provided from the resistor string RS 9  according to a selection value. 
     The resistor string RS 8  may generate intermediate voltages between the third reference voltage VT and the 87-grayscale voltage RV 87 . The multiplexer MX 9  may output a 51-grayscale voltage RV 51  by selecting one of the intermediate voltages provided from the resistor string RS 8  according to a selection value. 
     The resistor string RS 7  may generate intermediate voltages between the third reference voltage VT and the 51-grayscale voltage RV 51 . The multiplexer MX 8  may output a 35-grayscale voltage RV 35  by selecting one of the intermediate voltages provided from the resistor string RS 7  according to a selection value. 
     The resistor string RS 6  may generate intermediate voltages between the third reference voltage VT and the 35-grayscale voltage RV 35 . The multiplexer MX 7  may output a 23-grayscale voltage RV 23  by selecting one of the intermediate voltages provided from the resistor string RS 6  according to a selection value. 
     The resistor string RS 5  may generate intermediate voltages between the third reference voltage VT and the 23-grayscale voltage RV 23 . The multiplexer MX 6  may output an 11-grayscale voltage RV 11  by selecting one of the intermediate voltages provided from the resistor string RS 5  according to a selection value. 
     The resistor string RS 4  may generate intermediate voltages between the first reference voltage VH and the 11-grayscale voltage RV 11 . The multiplexer MX 5  may output a 7-grayscale voltage RV 7  by selecting one of the intermediate voltages provided from the resistor string RS 4  according to a selection value. 
     The resistor string RS 3  may generate intermediate voltages between the first reference voltage VH and the 7-grayscale voltage RV 7 . The multiplexer MX 4  may output a 1-grayscale voltage RV 1  by selecting one of the intermediate voltages provided from the resistor string RS 3  according to a selection value. 
     The resistor string RS 2  may generate intermediate voltages between the first reference voltage VH and the 1-grayscale voltage RV 1 . The multiplexer MX 3  may output a 0-grayscale voltage RV 0  by selecting one of the intermediate voltages provided from the resistor string RS 2  according to a selection value. 
     The above-described grayscales 0, 1, 7, 11, 23, 35, 51, 87, 151, 203, and 255 may be referred to as reference grayscales. In addition, the grayscale voltages RV 0 , RV 1 , RV 7 , RV 11 , RV 23 , RV 35 , RV 51 , RV 87 , RV 151 , RV 203 , and RV 255  generated from the multiplexers MX 2  to MX 12  may be referred to as reference grayscale voltages. A number of reference grayscales and grayscale numbers corresponding to the reference grayscales may be differently set depending on products. Hereinafter, for convenience of description, the grayscales 0, 1, 7, 11, 23, 35, 51, 87, 151, 203, and 255 are described as reference grayscales. 
     The grayscale voltage output unit  1512  may generate all grayscale voltages RV 0  to RV 255  by dividing the reference grayscale voltages RV 0 , RV 1 , RV 7 , RV 11 , RV 23 , RV 35 , RV 51 , RV 87 , RV 151 , RV 203 , and RV 255 . For example, the grayscale voltage output unit  1512  may generate RV 2  to RV 6  by dividing the reference grayscale voltages RV 1  and RV 7 . 
       FIGS. 9 and 10  are diagrams illustrating a case where pixels emit white color light according to a maximum luminance value according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 9 , a disposition example of the pixel unit  14  is partially illustrated. As described above, in  FIG. 9 , pixels are illustrated based on the positions of light emitting diodes of the pixel unit  14 , and scan lines SL 1  to SL 7  and data lines DL 1  to DL 7  are illustrated so as to describe an electrical coupling relationship of the pixel unit  14 . 
     Pixels RP 22 , RP 26 , RP 44 , RP 62 , and RP 66  may be pixels emitting light of the first color. Pixels GP 11 , GP 13 , GP 15 , GP 17 , GP 31 , GP 33 , GP 35 , GP 37 , GP 51 , GP 53 , GP 55 , GP 57 , GP 71 , GP 73 , GP 75 , and GP 77  may be pixels emitting light of the second color. Pixels BP 24 , BP 42 , BP 46 , and BP 64  may be pixels emitting light of the third color. 
     In exemplary embodiments of the inventive concept, data voltages corresponding to grayscale voltages may be alternately applied to data lines DL 1 , DL 3 , DL 5 , and DL 7  of a first group and data lines DL 2 , DL 4 , and DL 6  of a second group. 
     For example, data voltages corresponding to the first color may be applied to the data lines DL 1 , DL 3 , DL 5 , and DL 7  of the first group. When a scan signal of a turn-on level is applied to the scan line SL 1 , corresponding data voltages are written in the pixels GP 11 , GP 13 , GP 15 , and GP 17 . When a scan signal of a turn-on level is applied to the scan line SL 3 , corresponding data voltages are written in the pixels GP 31 , GP 33 , GP 35 , and GP 37 . When a scan signal of a turn-on level is applied to the scan line SL 5 , corresponding data voltages are written in the pixels GP 51 , GP 53 , GP 55 , and GP 57 . When a scan signal of a turn-on level is applied to the scan line SL 7 , corresponding data voltages are written in the pixels GP 71 , GP 73 , GP 75 , and GP 77 . 
     In addition, data voltages corresponding to the second color or the third color may be applied to the data lines DL 2 , DL 4 , and DL 6  of the second group. When a scan signal of a turn-on level is applied to the scan line SL 2 , corresponding data voltages are written in the pixels RP 22 , BP 24 , and RP 26 . When a scan signal of a turn-on level is applied to the scan line SL 4 , corresponding data voltages are written in the pixels BP 42 , RP 44 , and BP 46 . When a scan signal of a turn-on level is applied to the scan line SL 6 , corresponding data voltages are written in the pixels RP 62 , BP 64 , and RP 66 . 
       FIG. 10  illustrates white color light curves WC 1 , WC 2 , . . . , WC(k−1), and WCk of output luminances with respect to input grayscale values. Here, k may be an integer greater than 0. 
     Maximum luminance values of the white color light curves WC 1  to WCk may be different from one another. For example, the maximum luminance (e.g., 4 nits) of the white color light curve WC 1  may be lowest, and the maximum luminance value (e.g., 1200 nits) of the white color light curve WCk may be highest. 
     To generate white light, it is assumed that the pixels of the pixel unit  14  receive data voltages with respect to the same grayscale. 
     Imaginary dots illustrated on the white color light curves WC 1  to WCk shown in  FIG. 10  may correspond to the selection values pre-stored in the above-described selection value provider  1511 . More accurate white color light curves may be directly expressed as the number of selection values is increased. However, physical devices such as multiplexers, registers, etc., which correspond to the increased number of selection values, may be further required, and therefore, a limitation exists. Accordingly, the selection values with respect to the above-described reference grayscale voltage may be pre-stored and used, and the other grayscale voltages may be generated by dividing the reference grayscale voltages. In addition, for the same reason, selection values with respect to some maximum luminance values (e.g., reference maximum luminance values) between 4 nits and 1200 nits may be pre-stored and used, and the other maximum luminance values may be generated by interpolating the selection values. 
     The pre-stored selection values may be set for each individual product through Multi-Time Programming (MTP). In other words, selection values may be set through repetitive measurements to be stored in a product, so that white color light with a desired luminance can be emitted with respect to grayscale values. 
     In other words, the pre-stored selection values may be values set with respect to the white color light. As described above, when mixed color light or single color light instead of the white color light is emitted using set grayscale voltages, the luminance of the mixed color light or the single color light does not accurately correspond to a desired gamma curve. The gamma curve may correspond to a white color light curve. 
       FIG. 11  is a diagram illustrating a white color light curve and single color light curves at an arbitrary maximum luminance value according to an exemplary embodiment of the inventive concept. 
     As described above, when single color light instead of the white color light is emitted using the set grayscale voltages, the luminance of the single color light does not accurately correspond to a desired gamma curve. The gamma curve may correspond to a white color light curve WC. In addition, low grayscale expression is uncertain since luminance differences between low grayscales are insufficient. 
     The gamma curve may generally follow the following Equation 1. 
         y=ax   GM   +b   Equation 1
 
     Here, x may be a grayscale value, y may be a luminance value, a and b may be arbitrary constants, and GM may be a gamma value. 
     Hereinafter, for convenience of description, the constants a and b are neglected, shapes of curves are described using the gamma value GM. When the gamma value corresponds to 1, a straight line instead of a curve is drawn, and a curve becomes convex adjacent to the x axis as the gamma value is greater than 1. 
     Therefore, a gamma value of a first single color light curve RWC may be greater than that of the white color light curve WC. In addition, a gamma value of a second single color light curve GWC may be greater than that of the white color light curve WC and be smaller than that of the first single color light curve RWC. In addition, a gamma value of a third single color light curve BWC may be smaller than that of the white color light curve WC. For example, a first color may be the red color, a second color may be the green color, and a third color may be the blue color. 
     Therefore, although the same input grayscale value is expressed when single color light is emitted and when the white color light is emitted, the selection values of the selection value provider  1511  are preferably different from one another. However, as described above, physical devices such as multiplexers are further required when the selection values of the selection value provider  1511  are directly increased, which is not preferable. 
     Accordingly, in the present exemplary embodiment, a method is provided for checking whether unit areas emit single color light, double mixed color light, triple mixed color light, or white color light, and correcting an input grayscale value to a converted grayscale value, if necessary. When such a method is used, it is unnecessary to modify the existing grayscale voltage generator  15 , and thus the product configuration of the display device can be easily achieved. 
     The case shown in  FIG. 11  will be described as an example. The gamma value of the first single color light curve RWC is decreased by correcting the input grayscale value, so that the first single color light curve RWC can be adjusted to become similar to the white color light curve WC. 
     Similarly, the gamma value of the second single color light curve GWC is decreased by correcting the input grayscale value, so that the second single color light curve GWC can be adjusted to become similar to the white color light curve WC. A decrement in the gamma value of the second single color curve GWC may be smaller than that in the gamma value of the first single color light curve RWC. 
     Similarly, the gamma value of the third single color light curve BWC is decreased by correcting the input grayscale value, so that the third single color light curve BWC can be adjusted to become similar to the white color light curve WC. 
     In accordance with the above-described exemplary embodiments, luminances of single color lights can be accurately expressed according a desired gamma curve. In addition, low grayscale expression can be further clarified. 
     The above-described contents may be equally applied to the cases of double mixed color light and triple mixed color light. Thus, the input grayscale value is corrected, so that the double mixed color light curve can be adjusted to become similar to the white color light curve WC. In addition, the input grayscale value is corrected, so that the triple mixed color light curve can be adjusted to become similar to the white color light curve WC. 
     However, in the case of the white color light, the selection values have already been set to be suitable for the white color light, and thus it is unnecessary to separately perform grayscale correction. 
       FIGS. 12 to 26  are diagrams illustrating observation pixels according to a color of a target pixel, a unit area, a single color, a double mixed color, a triple mixed color, and a white color according to exemplary embodiments of the inventive concept. 
     Referring to  FIGS. 12 to 16 , a case where a target pixel GP 33  is a pixel of the second color is illustrated. 
     The target pixel GP 33  may emit light of the second color. First color observation pixels RP 22  and RP 44  are located adjacent to the target pixel GP 33 , and may emit light of the first color. Third color observation pixels BP 24  and BP 42  are located adjacent to the target pixel GP 33 , and may emit light of the third color. 
     A unit area OGA may be an area including the target pixel GP 33  and the observation pixels RP 22 , BP 24 , BP 44 , and RP 44 . The observation pixels RP 22 , BP 24 , BP 44 , and RP 44  may be set as pixels located at a most adjacent distance from the target pixel GP 33 . Therefore, no other pixels exist between the target pixel GP 33  and the observation pixels RP 22 , BP 24 , BP 44 , and RP 44 . The most adjacent distance may refer to a distance between the centers of pixels. 
     Grayscale values constituting an image frame may be differently referred to as input grayscale values and observation grayscale values according to their usage. For example, a grayscale value of an image frame corresponding to the target pixel GP 33  may be referred to as an input grayscale value. Grayscale values of an image frame corresponding to the first color observation pixels RP 22  and RP 44  may be referred to as first color observation grayscale values. In addition, grayscale values of an image frame corresponding to the third color observation pixels BP 24  and BP 42  may be referred to as third color observation grayscale values. 
     Referring to  FIG. 12 , in the unit area OGA, the target pixel GP 33  is in an emission state, and the observation pixels RP 22 , BP 24 , BP 42 , and RP 44  are in a non-emission state. The unit area OGA may emit single color light of the second color. 
     Emission and non-emission may be sorted according to grayscale values. In other words, a pixel receiving a grayscale value that exceeds a reference value may be sorted as an emission pixel (the emission state), and a pixel receiving a grayscale value that is the reference value or less may be sorted as a non-emission pixel (the non-emission state). For example, the reference value may be grayscale 0 or a specific low grayscale. The reference value may be appropriately set depending on products. 
     Referring to  FIG. 13 , in the unit area OGA, the target pixel GP 33  is in the emission state, the first color observation pixel RP 22  is in the emission state, and the other observation pixels BP 24 , BP 42 , and RP 44  are in the non-emission state. The unit area OGA may emit double mixed color light. When the first color is the red color and the second color is the green color, the double mixed color light in  FIG. 13  may be the yellow color. 
     Although not shown in the drawing, in the unit area OGA, the target pixel GP 33  may be in the emission state, the first color observation pixels RP 22  and RP 44  may be in the emission state, and the other observation pixels BP 24  and BP 42  may be in the non-emission state. The unit area OGA may emit double mixed color light of the yellow color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 13 . 
     Referring to  FIG. 14 , in the unit area OGA, the target pixel GP 33  is in the emission state, the third color observation pixel BP 24  is in the emission state, and the other observation pixels RP 22 , BP 42 , and RP 44  are in the non-emission state. The unit area OGA may emit double mixed color light. When the second color is the green color and the third color is the blue color, the double mixed color light in  FIG. 14  may be light of the cyan color. 
     Although not shown in the drawing, in the unit area OGA, the target pixel GP 33  may be in the emission state, the third color observation pixels BP 24  and BP 42  may be in the emission state, and the other observation pixels RP 22  and RP 44  may be in the non-emission state. The unit area OGA may emit double mixed color light of the cyan color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 14 . 
     Referring to  FIG. 15 , in the unit area OGA, the target pixel GP 33  is in the emission state, the first color observation pixel RP 22  is in the emission state, the third color observation pixel BP 24  is in the emission state, and the other observation pixels BP 42  and RP 44  are in the non-emission state. The unit area OGA may emit triple mixed color light. However, in the present exemplary embodiment, when all the pixels RP 22 , BP 24 , GP 33 , BP 42 , and RP 44  of the unit area OGA are in the emission state, light emitted from the unit area OGA is not determined as triple mixed color light. Triple mixed color light curves may be different from each other depending on emission combinations of the observation pixels. 
     Referring to  FIG. 16 , a case where all the pixels RP 22 , BP 24 , GP 33 , BP 42 , and RP 44  of the unit area OGA are in the emission state is illustrated. The unit area OGA may emit white color light. The white color light means light emitted when all the pixels RP 22 , BP 24 , GP 33 , BP 42 , and RP 44  of the unit area OGA are in the emission state, and input grayscale values and observation grayscale values are not considered. In other words, when all input grayscale values and observation grayscale values of the unit area OGA exceed the reference value, it is determined that the unit area OGA emits the white color light. As described above, it is unnecessary to separately perform correction on a white color light curve. 
     Referring to  FIGS. 17 to 21 , a case where a target pixel RP 44  is a pixel of the first color is illustrated. 
     The target pixel RP 44  may emit light of the first color. Second color observation pixels GP 33 , GP 35 , GP 53 , and GP 55  are located adjacent to the target pixel RP 44 , and may emit light of the second color. Third color observation pixels BP 24 , BP 42 , BP 46 , and BP 64  are located adjacent to the target pixel RP 44 , and may emit light of the third color. 
     In this example, the target pixel RP 44  is connected to a scan line SL 4  and a data line DL 4 . The second color observation pixels GP 33 , GP 35 , GP 53 , and GP 55  are connected to scan lines SL 3  and SL 5  adjacent to the scan line SL 4 . The third color observation pixels BP 24 , BP 42 , BP 46 , and BP 64  are connected to the same scan line or the same data line as the target pixel RP 44 . For example, the third color observation pixels BP 24  and BP 64  are connected to the data line DL 4 . The third color observation pixels BP 42  and BP 46  are connected to the scan line SL 4 . 
     A unit area ORA may be an area including the target pixel RP 44  and the observation pixels BP 24 , GP 33 , GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64 . The second color observation pixels GP 33 , GP 35 , GP 53 , and GP 55  may be set as second color pixels located at a most adjacent distance from the target pixel RP 44 . The third color observation pixels BP 24 , BP 42 , BP 46 , and BP 64  may be set as third color pixels located at a most adjacent distance from the target pixel RP 44 . Therefore, no other pixels exist between the target pixel RP 44  and the observation pixels BP 24 , GP 33 , GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64 . 
     Referring to  FIG. 17 , in the unit area ORA, the target pixel RP 44  is in the emission state, and the observation pixels BP 24 , GP 33 , GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64  are in the non-emission state. The unit area ORA may emit single color light of the first color. 
     Referring to  FIG. 18 , in the unit area ORA, the target pixel RP 44  is in the emission state, the second color observation pixel GP 33  is in the emission state, and the other observation pixels BP 24 , GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64  are in the non-emission state. The unit area ORA may emit double mixed color light. When the first color is the red color and the second color is the green color, the double mixed color light in  FIG. 18  may be light of the yellow color. 
     Although not shown in the drawing, in the unit area ORA, the target pixel RP 44  may be in the emission state, two or more second color observation pixels may be in the emission state, and the other observation pixels may be in the non-emission state. The unit area ORA may emit double mixed color light of the yellow color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 18 . 
     Referring to  FIG. 19 , in the unit area ORA, the target pixel RP 44  is in the emission state, the third color observation pixel BP 24  is in the emission state, and the other observation pixels GP 33 , GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64  are in the non-emission state. The unit area ORA may emit double mixed color light. When the first color is the red color and the third color is the blue color, the double mixed color light in  FIG. 19  may be light of the magenta color. 
     Although not shown in the drawing, in the unit area ORA, the target pixel RP 44  may be in the emission state, two or more third color observation pixels may be in the emission state, and the other observation pixels may be in the non-emission state. The unit area ORA may emit double mixed color light of the magenta color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 19 . 
     Referring to  FIG. 20 , in the unit area ORA, the target pixel RP 44  is in the emission state, the second color observation pixel GP 33  is in the emission state, the third color observation pixel BP 24  is in the emission state, and the other observation pixels GP 35 , BP 42 , BP 46 , GP 53 , GP 55 , and BP 64  are in the non-emission state. The unit area ORA may emit triple mixed color light. However, in the present exemplary embodiment, when all the pixels BP 24 , GP 33 , GP 35 , BP 42 , RP 44 , BP 46 , GP 53 , GP 55 , and BP 64  of the unit area ORA are in the emission state, light emitted from the unit area ORA is not determined as triple mixed color light. Triple mixed color light curves may be different from one another depending on emission combinations of the observation pixels. 
     Referring to  FIG. 21 , in the unit area ORA, a case where all the pixels BP 24 , GP 33 , GP 35 , BP 42 , RP 44 , BP 46 , GP 53 , GP 55 , and BP 64  are in the emission state is illustrated. The unit area ORA may emit white color light. The white color light means light emitted when all the pixels BP 24 , GP 33 , GP 35 , BP 42 , RP 44 , BP 46 , GP 53 , GP 55 , and BP 64  are in the emission state, and input grayscale values and observation grayscale values are not considered. In other words, when all input grayscale values and observation grayscale values of the unit area ORA exceed the reference value, it is determined that the unit area ORA emits the white color light. As described above, it is unnecessary to separately perform correction on a white color light curve. 
     Referring to  FIGS. 22 to 26 , a target pixel BP 64  is a pixel of the third color is illustrated. 
     The target pixel BP 64  may emit light of the third color. First color observation pixels RP 44 , RP 62 , RP 66 , and RP 84  are located adjacent to the target pixel BP 64 , and may emit light of the first color. Second color observation pixels GP 53 , GP 55 , GP 73 , and GP 75  are located adjacent to the target pixel BP 64 , and may emit light of the second color. 
     A unit area OBA may be an area including the target pixel BP 64  and the observation pixels RP 44 , GP 53 , GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84 . The first color observation pixels RP 44 , RP 62 , RP 66 , and RP 84  may be set as first color pixels located at a most adjacent distance from the target pixel BP 64 . The second color observation pixels GP 53 , GP 55 , GP 73 , and GP 75  may be set as second color pixels located at a most adjacent distance from the target pixel BP 64 . Therefore, no other pixels exist between the target pixel BP 64  and the observation pixels RP 44 , GP 53 , GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84 . 
     Referring to  FIG. 22 , in the unit area OBA, the target pixel BP 64  is in the emission state, and the observation pixels RP 44 , GP 53 , GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84  are in the non-emission state. The unit area OBA may emit single color light of the third color. 
     Referring to  FIG. 23 , in the unit area OBA, the target pixel BP 64  is in the emission state, the first color observation pixel RP 44  is in the emission state, and the other observation pixels GP 53 , GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84  are in the non-emission state. The unit area OBA may emit double mixed color light. When the first color is the red color and the third color is the blue color, the double mixed color light in  FIG. 23  may be light of the magenta color. 
     Although not shown in the drawing, in the unit area OBA, the target pixel BP 64  may be in the emission state, two or more first color observation pixels may be in the emission state, and the other observation pixels may be in the non-emission state. The unit area OBA may emit double mixed color light of the magenta color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 23 . 
     Referring to  FIG. 24 , in the unit area OBA, the target pixel BP 64  is in the emission state, the second color observation pixel GP 53  is in the emission state, and the other observation pixels RP 44 , GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84  are in the non-emission state. The unit area OBA may emit double mixed color light. When the second color is the green color and the third color is the blue color, the double mixed color light in  FIG. 24  may be light of the cyan color. 
     Although not shown in the drawing, in the unit area OBA, the target pixel BP 64  may be in the emission state, two or more second color observation pixels may be in the emission state, and the other observation pixels may be in the non-emission state. The unit area OBA may emit double mixed color light of the cyan color. However, a double mixed color light curve in this case may be different from that in the case shown in  FIG. 24 . 
     Referring to  FIG. 25 , in the unit area OBA, the target pixel BP 64  is in the emission state, the first color observation pixel RP 44  is in the emission state, the second color observation pixel GP 53  is in the emission state, and the other observation pixels GP 55 , RP 62 , RP 66 , GP 73 , GP 75 , and RP 84  are in the non-emission state. The unit area OBA may emit triple mixed color light. However, in the present exemplary embodiment, when all the pixels RP 44 , GP 53 , GP 55 , RP 62 , BP 64 , RP 66 , GP 73 , GP 75 , and RP 84  of the unit area OBA are in the emission state, light emitted from the unit area OBA is not determined as triple mixed color light. Triple mixed color light curves may be different from one another depending on emission combinations of the observation pixels. 
     Referring to  FIG. 26 , a case where all the pixels RP 44 , GP 53 , GP 55 , RP 62 , BP 64 , RP 66 , GP 73 , GP 75 , and RP 84  of the unit area OBA are in the emission state is illustrated. The unit area OBA may emit white color light. The white color light means light emitted when all the pixels RP 44 , GP 53 , GP 55 , RP 62 , BP 64 , RP 66 , GP 73 , GP 75 , and RP 84  of the unit area OBA are in the emission state, and input grayscale values and observation grayscale values are not considered. In other words, when all input grayscale values and observation grayscale values of the unit area OBA exceed the reference value, it is determined that the unit area OBA emits the white color light. As described above, it is unnecessary to separately perform correction on a white color light curve. 
       FIG. 27  is a diagram illustrating a grayscale corrector in accordance with an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 27 , the grayscale corrector  16  may include a light emitting pixel counter  164 , a grayscale converter  165 , single color offset providers  1611 ,  1621 , and  1631 , double mixed color offset providers  1612 ,  1622 , and  1632 , and triple mixed color offset providers  1613 ,  1623 , and  1632 . 
     Hereinafter, a case where a target pixel emits light of the first color is assumed for convenience of description. The grayscale corrector  16  may convert an input grayscale value TIG corresponding to the target pixel with reference to second color observation grayscale values C 2 OG corresponding to second color observation pixels and third color observation grayscale values C 3 OG corresponding to third color observation pixels. 
     In a driving method of the display device, the grayscale converter  165  may receive the input grayscale value TIG corresponding to the target pixel, and the light emitting pixel counter  164  may receive the second color observation grayscale values C 2 OG and the third color observation grayscale values C 3 OG. 
     The light emitting pixel counter  164  may determine and provide a second color light emitting pixel number C 2 EN by counting a number of the second color observation grayscale values C 2 OG that exceed a reference value, and determine and provide a third color light emitting pixel number C 3 EN by counting a number of third color observation grayscale values C 3 OG that exceed the reference value. As described above, a pixel receiving a grayscale value that exceeds the reference value may be sorted as an emission pixel (the pixel is in an emission state). Thus, in other words, the second color light emitting pixel number is a number of the second color observation pixels in the emission state, and the third color light emitting pixel number is a number of the third color observation pixels in the emission state. The grayscale corrector  16  converts the input grayscale value TIG based on whether the second color observation pixels and the third color observation pixels are in an emission state. 
     For example, in the case shown in  FIG. 17 , the light emitting pixel counter  164  may determine the second color light emitting pixel number C 2 EN as 0, and determine the third color light emitting pixel number C 3 EN as 0. In the case shown in  FIG. 18 , the light emitting pixel counter  164  may determine the second color light emitting pixel number C 2 EN as 1, and determine the third color light emitting pixel number C 3 EN as 0. In the case shown in  FIG. 19 , the light emitting pixel counter  164  may determine the second color light emitting pixel number C 2 EN as 0, and determine the third color light emitting pixel number C 3 EN as 1. In the case shown in  FIG. 20 , the light emitting pixel counter  164  may determine the second color light emitting pixel number C 2 EN as 1, and determine the third color light emitting pixel number C 3 EN as 1. In the case shown in  FIG. 21 , the light emitting pixel counter  164  may determine the second color light emitting pixel number C 2 EN as 4, and determine the third color light emitting pixel number C 3 EN as 4. 
     The grayscale converter  165  may generate and provide a converted grayscale value TCG obtained by converting the input grayscale value TIG, based on the second color light emitting pixel number C 2 EN and the third color light emitting pixel number C 3 EN. For example, the grayscale converter  165  may generate the converted grayscale value TCG by adding an offset value to the input grayscale value TIG. 
     For example, when the second color light emitting pixel number C 2 EN is 0 and the third color light emitting pixel number C 3 EN is 0, the grayscale converter  165  may generate the converted grayscale value TCG by adding a corresponding offset value among single color offset values to the input grayscale value TIG (see  FIG. 17 ). 
     In addition, when the second color light emitting pixel number C 2 EN is greater than 0 and the third color light emitting pixel number C 3 EN is 0, the grayscale converter  165  may generate the converted grayscale value TCG by adding a corresponding offset value among double mixed color offset values to the input grayscale value TIG (see  FIG. 18 ). 
     In addition, when the second color light emitting pixel number C 2 EN is greater than 0, the third color light emitting pixel number C 3 EN is greater than 0, and the second color light emitting pixel number C 2 EN and the third color light emitting pixel number C 3 EN are not respectively equal to the number of second color observation pixels and the number of third color observation pixels, the grayscale converter  165  may generate the converted grayscale value TCG by adding a corresponding offset value among triple mixed color offset values to the input grayscale value TIG (see  FIG. 20 ). 
     In addition, when the second color light emitting pixel number C 2 EN is equal to the number of second color observation pixels and the third color light emitting pixel number C 3 EN is equal to the number of third color observation pixels, the grayscale converter  165  may determine the input grayscale value TIG as the converted grayscale value TCG. In other words, the offset value in this case may be 0 (see  FIG. 21 ). Thus, in all other cases, e.g., when the second color light emitting pixel number C 2 EN is not equal to a total number of the second color observation pixels, or the third color light emitting pixel number C 3 EN is not equal to a total number of the third color observation pixels, the converted grayscale value TCG is not equal to the input grayscale value TIG. As described above, the input grayscale value TIG added with an offset value is determined as the converted grayscale value TCG. 
     A first single color offset provider  1611  may provide first single color offset values. The first single color offset values may be single color offset values for the first color, and vary depending on the input maximum luminance value DBVI. 
     A second single color offset provider  1621  may provide second single color offset values. The second single color offset values may be single color offset values for the second color, and vary depending on the input maximum luminance value DBVI. 
     A third single color offset provider  1631  may provide third single color offset values. The third single color offset values may be single color offset values for the third color, and vary depending on the input maximum luminance value DBVI. 
     A first double mixed color offset provider  1612  may provide first double mixed color offset values. The first double mixed color offset values may be double mixed color offset values for a mixed color (e.g., the yellow color) of the first color and the second color or a mixed color (e.g., the magenta color) of the first color and the third color, with respect to a target pixel of the first color. 
     A second double mixed color offset provider  1622  may provide second double mixed color offset values. The second double mixed color offset values may be double mixed color offset values for a mixed color (e.g., the yellow color) of the second color and the first color or a mixed color (e.g., the cyan color) of the second color and the third color, with respect to a target pixel of the second color. 
     A third double mixed color offset provider  1622  may provide third double mixed color offset values. The third double mixed color offset values may be double mixed color offset values for a mixed color (e.g., the magenta color) of the third color and the first color or a mixed color (e.g., the cyan color) of the third color and the second color, with respect to a target pixel of the third color. 
     A first triple mixed color offset provider  1613  may provide first triple mixed color offset values. The first triple mixed color offset values may be triple mixed color offset values for a mixed color of the first color, the second color, and the third color, with respect to a target pixel of the first color. 
     A second triple mixed color offset provider  1623  may provide second triple mixed color offset values. The second triple mixed color offset values may be triple mixed color offset values for a mixed color of the first color, the second color, and the third color, with respect to a target pixel of the second color. 
     A third triple mixed color offset provider  1633  may provide third triple mixed color offset values. The third triple mixed color offset values may be triple mixed color offset values for a mixed color of the first color, the second color, and the third color, with respect to a target pixel of the third color. 
       FIGS. 28 to 30  are diagrams illustrating a single color offset provider according to an exemplary embodiment of the inventive concept. 
     In exemplary embodiments of the inventive concept, the first single color offset provider  1611  may include a first single color reference offset provider  16111  and a first single color total offset generator  16112 . The same description may be substantially applied to the second and third single color offset providers  1621  and  1631 , and therefore, overlapping descriptions will be omitted. 
     The first single color reference offset provider  16111  may receive the input maximum luminance value DBVI, and provide first single color reference offset values RRO 1 , RRO 2 , RRO 3 , RRO 4 , RRO 5 , RRO 6 , RRO 7 , RRO 8 , and RRO 9  corresponding to the input maximum luminance value DB VI. 
     When the second color light emitting pixel number is equal to the number of second color observation pixels and the third color light emitting pixel number is equal to the number of third color observation pixels, a converted grayscale value equal to the input grayscale value may be output by the grayscale converter  165  as described above. The relationship of converted grayscale values with respect to input grayscale values may follow a white color grayscale line RWL. 
     When the second color light emitting pixel number is 0 and the third color light emitting pixel number is 0, a converted grayscale value different from the input grayscale value may be output by the grayscale converter  165  as described above. In other words, the converted grayscale value may be generated by adding a corresponding offset value among first single color offset values RSO 0  to RSO 255  to the input grayscale value. The relationship of converted grayscale values with respect to input grayscale values may follow a first single color grayscale line RSL. 
     For example, when the input grayscale value is 1, the converted grayscale value may become 1 by adding a first single offset value RSO 1  that is 0 to the input grayscale value. When the input grayscale value 7, the converted grayscale value may become 24 by adding a first single color offset value RSO 7  that is 17 to the input grayscale value. When the input grayscale value is 11, the converted grayscale value may become 64 by adding a first single offset value RSO 11  that is 53 to the input grayscale value. When the input grayscale value is 23, the converted grayscale value may become 70 by adding a first single color offset value RSO 23  that is 47 to the input grayscale value. When the input grayscale value is 35, the converted grayscale value may become 75 by adding a first single color offset value RSO 35  that is 40 to the input grayscale value. When the input grayscale value is 51, the converted grayscale value may become 83 by adding a first single color offset value RSO 51  that is 32 to the input grayscale value. When the input grayscale value is 87, the converted grayscale value may become 107 by adding a first single color offset value RSO 87  that is 20 to the input grayscale value. When the input grayscale value is 151, the converted grayscale value may become 156 by adding a first single color offset value RSO 151  that is 5 to the input grayscale value. When the input grayscale value is 203, the converted grayscale value may become 206 by adding a first single color offset value RSO 203  that is 3 to the input grayscale value. When the input grayscale value is 255, the converted grayscale value may be 255. When the input grayscale value is 0, the converted grayscale value may be 0. 
     The first single offset values RSO 1 , RSO 7 , RSO 11 , RSO 23 , RSO 35 , RSO 51 , RSO 87 , RSO 151 , and RSO 203  may correspond to the first single color reference offset values RRO 1 , RRO 2 , RRO 3 , RRO 4 , RRO 5 , RRO 6 , RRO 7 , RRO 8 , and RRO 9 . 
     The first single color total offset generator  16112  may generate the first single color offset values RSO 1  to RSO 255  by interpolating the first single color reference offset values RRO 1  to RRO 9 . The interpolation method may use a conventional method such as linear interpolation, polynomial interpolation, or exponential interpolation. 
     For example, referring to  FIGS. 29 and 30 , the first single color total offset generator  16112  may generate a first single color offset value RSO 8  corresponding to the grayscale 8, a first single color offset value RSO 9  corresponding to the grayscale 9, and a first single color offset value RSO 10  corresponding to the grayscale 10 by interpolating a first reference offset value RRO 2  corresponding to the grayscale 7 and a first reference offset value RRO 3  corresponding to the grayscale 11. 
     Thus, in accordance with the present exemplary embodiment, it is unnecessary to store all first total offset values RSO 0  to RSO 255 , and accordingly, the configuration cost of a memory device, etc. can be reduced. 
       FIG. 31  is a diagram illustrating a configuration of an offset value according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 31 , an offset value RSO may include a sign bit SBT, an offset integer bit OIBT, and an offset decimal bit ODBT. 
     The sign bit SBT may express whether the offset value RSO is a positive number or negative number. For example, referring to  FIG. 11 , it may be necessary to decrease the gamma values of the first single color light curve RWC and the second single color light curve GWC, and therefore, the offset value RSO may be the positive number. On the other hand, it may be necessary to increase the gamma value of the third single color light curve BWC, and therefore, the offset value RSO may be the negative number. For example, the offset value RSO may represent the positive number when the sign bit SBT is 0, and represent the negative number when the sign bit SBT is 1. On the contrary, the offset value RSO may represent the positive number when the sign bit SBT is 1, and represent the negative number when the sign bit SBT is 0. 
     Like the case shown in  FIG. 30 , interpolated converted grayscale values 24, 44, 54, and 64 may be expressed with only integers, but it is necessary to express interpolated converted grayscale values with integers and decimals in some cases. For example, referring to  FIG. 29 , when 63 input grayscale values corresponding to between 87 and 151 are corrected as converted grayscale values between 107 and 156, the corrected converted grayscale values may be expressed with integers and decimals. Since the number of integers between 107 and 156 is 48, it is necessary to express a minimum of 15 converted grayscale values with integers and decimals. Therefore, the offset value RSO includes the offset integer bit OIBT and the offset decimal bit ODBT. 
     When the offset value RSO has a decimal value, the corrected converted grayscale value cannot express a corresponding luminance, using only one of the grayscale voltages RV 0  to RV 255  (see  FIG. 8 ). The display panel  10  spatially dithers a target pixel and adjacent pixels, to express a luminance corresponding to a converted grayscale value having a decimal value. 
       FIG. 32  is a diagram illustrating an effect obtained by applying a single color offset value according to an exemplary embodiment of the inventive concept. 
     A first single color light curve RWC represents a luminance when pixels emit light of a first single color according to input grayscale values. 
     A first single color light correction curve RSC represents a luminance when the pixels emit light of the first single color according to converted grayscale values obtained by correcting the input grayscale values. 
     For example, in accordance with an exemplary embodiment of the inventive concept, the display panel  10  may include a first pixel emitting light of a first color, a second pixel emitting light of a second color different from the first color, and a third pixel emitting light of a third color different from the first color and the second color. 
     A first luminance of the first pixel in a first case where the first pixel, the second pixel, and the third pixel emit lights and a second luminance of the first pixel in a second case where only the first pixel emits light and the second pixel and the third pixel do not emit light may be different from each other. 
     Input grayscale values provided corresponding to the first pixel in the first case and the second case may be equal to each other. 
     In other words, the first luminance with respect to the input grayscale value in the first case may follow the first single color light curve RWC, and the second luminance with respect to the input grayscale value in the second case may follow the first single color light correction curve RSC. 
     A gamma value of the first single color light correction curve RSC may be smaller than that of the first single color light curve RWC. Accordingly, the luminance of the first single color can be accurately expressed according to a desired gamma curve. In addition, low grayscale expression can be further clarified. 
     The above described exemplary embodiment may be substantially applied to second single color light and third single color light, and therefore, overlapping descriptions will be omitted. 
       FIGS. 33 and 34  are diagrams illustrating a single color reference offset provider according to an exemplary embodiment of the inventive concept. 
     In exemplary embodiments of the inventive concept, the first single color reference offset provider  16111  may include a first single color preset determiner  161111  and a first single color reference offset generator  161112 . 
     The first single color preset determiner  161111  may pre-store first preset offset values corresponding to preset maximum luminance values, and determine whether the input maximum luminance value DBVI corresponds to any one of the preset maximum luminance values. 
     For example, the preset maximum luminance values may include a maximum value (e.g., 1200 nits) and a minimum value (e.g., 4 nits) of the receivable input maximum luminance value DBVI. 
     Additionally, the preset maximum luminance values may further include a first intermediate maximum luminance value (e.g., 100 nits). When the input maximum luminance value is a value between the maximum value and the first intermediate maximum luminance value, a grayscale voltage corresponding to a converted grayscale value is adjusted corresponding to the input maximum luminance value DBVI, so that the luminance of a target pixel can be controlled. For example, the luminance of the target pixel in a section between 1200 nits and 100 nits may rely on a grayscale voltage control method. In addition, when the input maximum luminance value DBVI is a value between the minimum value and the first intermediate maximum luminance value, the emission period of the target pixel is adjusted corresponding to the input maximum luminance value DBVI, so that the luminance of the target pixel can be controlled. For example, the luminance of the target pixel in a section between 100 nits and 4 nits may rely on a duty ratio control method. 
     In addition, the preset maximum luminance values may further include a second intermediate maximum luminance value (e.g., 30 nits) that is a value between the first intermediate maximum luminance value and the minimum value. 
     The above-described four preset maximum luminance values (e.g., 1200 nits, 100 nits, 30 nits, and 4 nits) are merely an example, and other preset maximum luminance values may be set depending on products. 
     When the input maximum luminance value DBVI corresponds to any one of the preset maximum luminance values, the first single color preset determiner  161111  may provide corresponding first preset offset values DBVP 1  as the first single color reference offset values RRO 1  to RRO 9 . For example, first preset offset values DBVP 1  for 1200 nits, 100 nits, 30 nits, and 4 nits may be pre-stored. Therefore, when the input maximum luminance value DBVI corresponds to one of 1200 nits, 100 nits, 30 nits, and 4 nits, the first single color reference offset values RRO 1  to RRO 9  may be provided without passing through the first single color reference offset generator  161112 . 
     When the input maximum luminance value DBVI does not correspond to any one of the preset maximum luminance values, the first single color preset determiner  161111  may provide first preset offset values corresponding to at least two preset maximum luminance values. 
     For example, when the input maximum luminance value DBVI is 17 nits, the first single color preset determiner  161111  may provide first preset offset values DBVP 1  corresponding to 4 nits and second preset offset values DBVP 2  corresponding to 30 nits. 
     The first single color reference offset generator  161112  may generate the first single color reference offset values RRO 1  to RRO 9  by interpolating the first and second preset offset values DBVP 1  and DBVP 2  corresponding to the at least two preset maximum luminance values. 
     Referring to  FIG. 34 , a process of determining magnitudes of first reference offset values DBVG corresponding to 17 nits by interpolating the first preset offset values DBVP 1  corresponding to 4 nits and the second preset offset values DBVP 2  corresponding to 30 nits is expressed by a graph. 
     Thus, in accordance with the present exemplary embodiment, it is unnecessary to store all offset values with respect to the receivable input maximum luminance value DBVI, and accordingly, the configuration cost of a memory device, etc. can be reduced. 
       FIGS. 35 to 38  are diagrams illustrating a first double mixed color offset provider and a first triple mixed color offset provider according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 35 , the first double mixed color offset provider  1612  may include first double mixed color offset sub-units  1612 X 1 ,  1612 X 2 ,  1612 X 3 ,  1612 X 4 ,  1612 Y 1 ,  1612 Y 2 ,  1612 Y 3 , and  1612 Y 4 . 
     A first X 2  double mixed color offset sub-unit  1612 X 2  may provide first X 2  double mixed color offset values RX 20  to RX 2255  corresponding to when the second color light emitting pixel number is 2 and the third color light emitting pixel number is 0, with respect to a target pixel of the first color. 
     A first X 4  double mixed color offset sub-unit  1612 X 4  may provide first X 4  double mixed color offset values RX 40  to RX 4255  corresponding to when the second color light emitting pixel number is 4 and the third color light emitting pixel number is 0, with respect to a target pixel of the first color. 
     A first Y 2  double mixed color offset sub-unit  1612 Y 2  may provide first Y 2  double mixed color offset values RY 20  to RY 2255  corresponding to when the second color light emitting pixel number is 0 and the third color light emitting pixel number is 2, with respect to a target pixel of the first color. 
     A first Y 4  double mixed color offset sub-unit  1612 Y 4  may provide first Y 4  double mixed color offset values RY 40  to RY 4255  corresponding to when the second color light emitting pixel number is 0 and the third color light emitting pixel number is 4, with respect to a target pixel of the first color. 
     Referring to  FIG. 36 , the first X 4  double mixed color offset sub-unit  1612 X 4  may include a first X 4  double mixed color reference offset provider  16121 X 4  and a first X 4  double mixed color total offset generator  16122 X 4 . 
     The first X 4  double mixed color reference offset provider  16121 X 4  may provide first X 4  double mixed color reference offset values RX 4 R 0  to RX 4 R 255  corresponding to the input maximum luminance value DBVI. 
     The first X 4  double mixed color total offset generator  16122 X 4  may generate the first X 4  double mixed color offset values RX 40  to RX 4255  by interpolating first X 4  double mixed color reference offset values RX 4 R 1  to RX 4 R 9 . 
     A configuration and an operation of the first X 4  double mixed color offset sub-unit  1612 X 4  are substantially identical to those of the first single color offset provider  1611  shown in  FIG. 28 , and therefore, overlapping descriptions will be omitted. Likewise, the first X 2  double mixed color offset sub-unit  1612 X 2 , the first Y 2  double mixed color offset sub-unit  1612 Y 2 , and the first Y 4  double mixed color offset sub-unit  1612 Y 4  may be similarly configured, and therefore, overlapping descriptions will be omitted. 
     A first X 1  double mixed color offset sub-unit  1612 X 1  may provide first X 1  double mixed color offset values RX 10  to RX 1255  corresponding to when the second color light emitting pixel number is 1 and the third color light emitting pixel number is 0, with respect to a target pixel of the first color. 
     For example, the first X 1  double mixed color offset sub-unit  1612 X 1  may generate the first X 1  double mixed color offset values RX 10  to RX 1255  by interpolating the first single color offset values RSO 0  to RSO 255  and the first X 2  double mixed color offset values RX 20  to RX 2255 . 
     Additionally, for example, the first X 1  double mixed color offset sub-unit  1612 X 1  may output the first X 2  double mixed color offset values RX 20  to RX 2255  as the first X 1  double mixed color offset values RX 10  to RX 1255 . 
     A first X 3  double mixed color offset sub-unit  1612 X 3  may provide double mixed color offset values RX 30  to RX 3255  corresponding to when the second color light emitting pixel number is 3 and the third color light emitting pixel number is 0, with respect to a target pixel of the first color. 
     For example, the first X 3  double mixed color offset sub-unit  1612 X 3  may generate first X 3  double mixed color offset values RX 30  to RX 3255  by interpolating the first X 2  double mixed color offset values RX 20  to RX 2255  and the first X 4  double mixed color offset values RX 40  to RX 4255 . 
     A first Y 1  double mixed color offset sub-unit  1612 Y 1  may provide double mixed color offset values RY 10  to RY 1255  corresponding to when the second color light emitting pixel number is 0 and the third color light emitting pixel number is 1, with respect to a target pixel of the first color. 
     For example, the first Y 1  double mixed color offset sub-unit  1612 Y 1  may generate first Y 1  double mixed color offset values RY 10  to RY 1255  by interpolating the first single color offset values RSO 0  to RSO 255  and the first Y 2  double mixed color offset values RY 20  to RY 2255 . 
     Additionally, for example, the first Y 1  double mixed color offset sub-unit  1612 Y 1  may output the first Y 2  double mixed color offset values RY 20  to RY 2255  as the first Y 1  double mixed color offset values RY 10  to RY 1255 . 
     A first Y 3  double mixed color offset sub-unit  1612 Y 3  may provide double mixed color offset values RY 30  to RY 3255  corresponding to when the second color light emitting pixel number is 0 and the third color light emitting pixel number  3 , with respect to a target pixel of the first color. 
     For example, the first Y 3  double mixed color offset sub-unit  1612 Y 3  may provide first Y 3  double mixed color offset values RY 30  to RY 3255  by interpolating the first Y 2  double mixed color offset values RY 20  to RY 2255  and the first Y 4  double mixed color offset values RY 40  to RY 4255 . 
     In accordance with the present exemplary embodiment, when a unit area ORA displays a double mixed color (e.g., the magenta color and the yellow color), double mixed color light curves can be adjusted to become similar to a white color light curve. 
     Referring to  FIG. 37 , the first triple mixed color offset provider  1613  may include first triple mixed color offset sub-units  1613 X 1 Y 1 ,  1613 X 1 Y 2 ,  1613 X 1 Y 3 ,  1613 X 1 Y 4 ,  1613 X 2 Y 1 ,  1613 X 2 Y 2 ,  1613 X 2 Y 3 ,  1613 X 2 Y 4 ,  1613 X 3 Y 1 ,  1613 X 3 Y 2 ,  1613 X 3 Y 3 ,  1613 X 3 Y 4 ,  1613 X 4 Y 1 ,  1613 X 4 Y 2 , and  1613 X 4 Y 3 . 
     A first X 1 Y 1  triple mixed color offset sub-unit  1613 X 1 Y 1  may provide first X 1 Y 1  triple mixed color offset values RX 1 Y 10  to RX 1 Y 1255  corresponding to when the second color light emitting pixel number is 1 and the third color light emitting pixel number is 1, with respect to a target pixel of the first color. 
     For example, the first X 1 Y 1  triple mixed color offset sub-unit  1613 X 1 Y 1  may generate the first X 1 Y 1  triple mixed color offset values RX 1 Y 10  to RX 1 Y 1255  by using double mixed color offset values corresponding to a total sum (here, 2) of light emitting pixel numbers. 
     For example, the first X 1 Y 1  triple mixed color offset sub-unit  1613 X 1 Y 1  may generate the first X 1 Y 1  triple mixed color offset values RX 1 Y 10  to RX 1 Y 1255  by using the first X 2  double mixed color offset values RX 20  to RX 2255  and the first Y 2  double mixed color offset values RY 20  to RY 2255 . 
     For example, the first X 1 Y 1  triple mixed color offset values RX 1 Y 10  to RX 1 Y 1255  may be determined using the following Equation 2. 
     
       
         
           
             
               
                 
                   
                     RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                   
                   = 
                   
                     W_RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     * 
                     
                       
                         
                           X_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           * 
                           RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                         + 
                         
                           Y_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           * 
                           RY 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                       
                         
                           X_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                         
                         + 
                         
                           Y_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                         
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   2 
                 
               
             
           
         
       
     
     Here, RX 1 Y 1  may be a first X 1 Y 1  triple mixed color offset value corresponding to an input grayscale value, W_RX 1 Y 1  may be a weighted value, X_RX 1 Y 1  may be 1 as the second color light emitting pixel number, Y_RX 1 Y 1  may be 1 as the third color light emitting pixel number, RX 2  may be a first X 2  double mixed color offset value corresponding to the input grayscale value, and RY 2  may be a first Y 2  double mixed color offset value corresponding to the input grayscale value. The weighted value W_RX 1 Y 1  may be increased as the input grayscale value is increased. The weighted value W_RX 1 Y 1  may be a real number that is 0 or more and is 1 or less. The weighted value W_RX 1 Y 1  may vary depending on the input maximum luminance value DBVI. 
     A first X 1 Y 2  triple mixed color offset sub-unit  1613 X 1 Y 2  may provide first X 1 Y 2  triple mixed color offset values RX 1 Y 20  to RX 1 Y 2255  corresponding to when the second color light emitting pixel number is 1 and the third color light emitting pixel number is 2, with respect to a target pixel of the first color. 
     For example, the first X 1 Y 2  triple mixed color offset sub-unit  1613 X 1 Y 2  may generate the first X 1 Y 2  triple mixed color offset values RX 1 Y 20  to RX 1 Y 2255  by using double mixed color offset values corresponding to a total sum (here, 3) of light emitting pixel numbers. 
     For example, the first X 1 Y 2  triple mixed color offset sub-unit  1613 X 1 Y 2  may generate the first X 1 Y 2  triple mixed color offset values RX 1 Y 20  to RX 1 Y 2255  by using the first X 3  double mixed color offset values RX 30  to RX 3255  and the first Y 3  double mixed color offset values RY 30  to RY 3255 . 
     For example, the first X 1 Y 2  triple mixed color offset values RX 1 Y 20  to RX 1 Y 2255  may be determined using the following Equation 3. 
     
       
         
           
             
               
                 
                   
                     RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                   
                   = 
                   
                     W_RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                     * 
                     
                       
                         
                           X_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           * 
                           RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           3 
                         
                         + 
                         
                           Y_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           * 
                           RY 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           3 
                         
                       
                       
                         
                           X_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                         + 
                         
                           Y_RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           1 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   3 
                 
               
             
           
         
       
     
     Here, RX 1 Y 2  may be a first X 1 Y 2  triple mixed color offset value corresponding to an input grayscale value, W_RX 1 Y 2  may be a weighted value, X_RX 1 Y 2  may be 1 as the second color light emitting pixel number, Y_RX 1 Y 2  may be 2 as the third color light emitting pixel number, RX 3  may be a first X 3  double mixed color offset value corresponding to the input grayscale value, and RY 3  may be a first Y 3  double mixed color offset value corresponding to the input grayscale value. The weighted value W_RX 1 Y 2  may be increased as the input grayscale value is increased. The weighted value W_RX 1 Y 2  may be a real number that is 0 or more and is 1 or less. The weighted value W_RX 1 Y 2  may vary depending on the input maximum luminance value DBVI. 
     A first X 2 Y 1  triple mixed color offset sub-unit  1613 X 2 Y 1  may provide first X 2 Y 1  triple mixed color offset values RX 2 Y 10  to RX 2 Y 1255  corresponding to when the second color light emitting pixel number is 2 and the third color light emitting pixel number is 1, with respect to a target pixel of the first color. For example, the first X 2 Y 1  triple mixed color offset sub-unit  1613 X 2 Y 1  may generate the first X 2 Y 1  triple mixed color offset values RX 2 Y 10  to RX 2 Y 1255  by using the first X 3  double mixed color offset values RX 30  to RX 3255  and the first Y 1  double mixed color offset values RY 30  to RY 3255 . Therefore, its overlapping description will be omitted. 
     A first X 3 Y 1  triple mixed color offset sub-unit  1613 X 3 Y 1  may provide first X 3 Y 1  triple mixed color offset values RX 3 Y 10  to RX 3 Y 1255  corresponding to when the second color light emitting pixel number is 3 and the third color light emitting pixel is 1, with respect to a target pixel of the first color. For example, the first X 3 Y 1  triple mixed color offset sub-unit  1613 X 3 Y 1  may generate the first X 3 Y 1  triple mixed color offset values RX 3 Y 10  to RX 3 Y 1255  by using the first X 4  double mixed color offset values RX 40  to RX 4255  and the first Y 4  double mixed color offset values RY 40  to RY 4255 . Therefore, its overlapping description will be omitted. 
     A first X 2 Y 2  triple mixed color offset sub-unit  1613 X 2 Y 2  may provide first X 2 Y 2  triple mixed color offset values RX 2 Y 20  to RX 2 Y 2255  corresponding to when the second color light emitting pixel number is 2 and the third color light emitting pixel number is 2, with respect to a target pixel of the first color. For example, the first X 2 Y 2  triple mixed color offset sub-unit  1613 X 2 Y 2  may generate the first X 2 Y 2  triple mixed color offset values RX 2 Y 20  to RX 2 Y 2255  by using the first X 4  double mixed color offset values RX 40  to RX 4225  and the first Y 4  double mixed color offset values RY 40  to RY 4255 . Therefore, its overlapping description will be omitted. 
     A first X 1 Y 3  triple mixed color offset sub-unit  1613 X 1 Y 3  may provide first X 1 Y 3  triple mixed color offset values RX 1 Y 30  to RX 1 Y 3255  corresponding to when the second color light emitting pixel number is 1 and the third color light emitting pixel number is 3, with respect to a target pixel of the first color. For example, the first X 1 Y 3  triple mixed color offset sub-unit  1613 X 1 Y 3  may generate the first X 1 Y 3  triple mixed color offset values RX 1 Y 30  to RX 1 Y 3255  by using the first X 4  double mixed color offset values RX 40  to RX 4255  and the first Y 4  double mixed color offset values RY 40  to RY 4255 . Therefore, its overlapping description will be omitted. 
     A first X 3 Y 3  triple mixed color offset sub-unit  1613 X 3 Y 3  may provide first X 3 Y 3  triple mixed color offset values RX 3 Y 30  to RX 3 Y 3255  corresponding to when the second color light emitting pixel number is 3 and the third color light emitting pixel number is 3, with respect to a target pixel of the first color. For example, the first X 3 Y 3  triple mixed color offset values RX 3 Y 30  to RX 3 Y 3255  may be determined using the following Equation 4. 
     
       
         
           
             
               
                 
                   
                     RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                   
                   = 
                   
                     W_RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                     * 
                     
                       
                         
                           RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           4 
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           4 
                         
                         + 
                         
                           RX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                       
                         
                             
                         
                         ⁢ 
                         2 
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   4 
                 
               
             
           
         
       
     
     Here, RX 3 Y 3  may be a first X 3 Y 3  triple mixed color offset value corresponding to an input grayscale value, W_RX 3 Y 3  may be a weighted value, RX 4 Y 4  may be a white color offset value corresponding to the input grayscale value, and RX 2 Y 2  may be a first X 2 Y 2  triple mixed color offset value corresponding to the input grayscale value. The weighted value W_RX 3 Y 3  may be increased as the input grayscale value is increased. The weighted value W_RX 3 Y 3  may be a real number that is 0 or more and is 1 or less. The weighted value W_RX 3 Y 3  may vary depending on the input maximum luminance value DBVI. RX 4 Y 4  may be 0. 
     A first X 3 Y 2  triple mixed color offset sub-unit  1613 X 3 Y 2  may provide first X 3 Y 2  triple mixed color offset values RX 3 Y 20  to RX 3 Y 2255  corresponding to when the second color light emitting pixel number is 3 and the third color light emitting pixel number is 2, with respect to a target pixel of the first color. For example, the first X 3 Y 2  triple mixed color offset values RX 3 Y 20  to RX 3 Y 2255  may be determined using the following Equation 5. 
     
       
         
           
             
               
                 
                   
                     RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                   
                   = 
                   
                     
                       
                         RX 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                         ⁢ 
                         Y 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                       
                       + 
                       
                         RX 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         Y 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         1 
                       
                     
                     
                       
                           
                       
                       ⁢ 
                       2 
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   5 
                 
               
             
           
         
       
     
     Here, RX 3 Y 2  may be a first X 3 Y 2  triple mixed color offset value corresponding to an input grayscale value, RX 3 Y 3  may be a first X 3 Y 3  triple mixed color offset value corresponding to the input grayscale value, and RX 3 Y 1  may be a first X 3 Y 1  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 2 Y 3  triple mixed color offset sub-unit  1613 X 2 Y 3  may provide first X 2 Y 3  triple mixed color offset values RX 2 Y 30  to RX 2 Y 3255  corresponding to when the second color light emitting pixel number is 2 and the third color light emitting pixel number is 3, with respect to a target pixel of the first color. For example, the first X 2 Y 3  triple mixed color offset values RX 2 Y 30  to RX 2 Y 3255  may be determined using the following Equation 6. 
     
       
         
           
             
               
                 
                   
                     RX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     3 
                   
                   = 
                   
                     
                       
                         RX 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                         ⁢ 
                         Y 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                       
                       + 
                       
                         RX 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         1 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         Y 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         3 
                       
                     
                     
                       
                           
                       
                       ⁢ 
                       2 
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   6 
                 
               
             
           
         
       
     
     Here, RX 2 Y 3  may be a first X 2 Y 3  triple mixed color offset value corresponding to an input grayscale value, RX 3 Y 3  may be a first X 3 Y 3  triple mixed color offset value corresponding to the input grayscale value, and RX 1 Y 3  may be a first X 1 Y 3  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 4 Y 3  triple mixed color offset sub-unit  1613 X 4 Y 3  may provide first X 4 Y 3  triple mixed color offset values RX 4 Y 30  to RX 4 Y 3255  corresponding to when the second color light emitting pixel number is 4 and the third color light emitting pixel number is 3, with respect to a target pixel of the first color. For example, the first X 4 Y 3  triple mixed color offset values RX 4 Y 30  to RX 4 Y 3255  may be determined using the following Equation 7. 
         RX 4 Y 3= RX 3 Y 3−( RX 3 Y 3− RX 2 Y 2)  Equation 7
 
     Here, RX 4 Y 3  may be a first X 4 Y 3  triple mixed color offset value corresponding to an input grayscale value, RX 3 Y 3  may be a first X 3 Y 3  triple mixed color offset value corresponding to the input grayscale value, and RX 2 Y 3  may be a first X 2 Y 3  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 3 Y 4  triple mixed color offset sub-unit  1613 X 3 Y 4  may provide first X 3 Y 4  triple mixed color offset values RX 3 Y 40  to RX 3 Y 4255  corresponding to when the second color light emitting pixel number is 3 and the third color light emitting pixel number is 4, with respect to a target pixel of the first color. For example, the first X 3 Y 4  triple mixed color offset values RX 3 Y 40  to RX 3 Y 4255  may be determined using the following Equation 8. 
         RX 3 Y 4= RX 3 Y 3+( RK 3 Y 3− RX 3 Y 2)  Equation 8
 
     Here, RX 3 Y 4  may be a first X 3 Y 4  triple mixed color offset value corresponding to an input grayscale value, RX 3 Y 3  may be a first X 3 Y 3  triple mixed color offset value corresponding to the input grayscale value, and RX 3 Y 2  may be a first X 3 Y 2  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 2 Y 4  triple mixed color offset sub-unit  1613 X 2 Y 4  may provide first X 2 Y 4  triple mixed color offset values RX 2 Y 40  to RX 2 Y 4255  corresponding to when the second color light emitting pixel number is 2 and the third color light emitting pixel number is 4, with respect to a target pixel of the first color. For example, the first X 2 Y 4  triple mixed color offset values RX 2 Y 40  to RX 2 Y 4255  may be determined using the following Equation 9. 
         RX 2 Y 4= RX 3 Y 4+( RX 3 Y 4− RX 4 Y 4)  Equation 9
 
     Here, RX 2 Y 4  may be a first X 2 Y 4  triple mixed color offset value corresponding to an input grayscale value, RX 3 Y 4  may be a first X 3 Y 4  triple mixed color offset value corresponding to the input grayscale value, and RX 4 Y 4  may be a white color offset value corresponding to the input grayscale value. RX 4 Y 4  may be 0. 
     A first X 4 Y 2  triple mixed color offset sub-unit  1613 X 4 Y 2  may provide first X 4 Y 2  triple mixed color offset values RX 4 Y 20  to RX 4 Y 2255  corresponding to when the second color light emitting pixel number is 4 and the third color light emitting pixel number is 2, with respect to a target pixel of the first color. For example, the first X 4 Y 2  triple mixed color offset values RX 4 Y 20  to RX 4 Y 2255  may be determined using the following Equation 10. 
         RX 4 Y 2= RX 4 Y 3+( RX 4 Y 3− RX 4 Y 4)  Equation 10
 
     Here, RX 4 Y 2  may be a first X 4 Y 2  triple mixed color offset value corresponding to an input grayscale value, RX 4 Y 3  may be a first X 4 Y 3  triple mixed color offset value corresponding to the input grayscale value, and RX 4 Y 4  may be a first X 4 Y 4  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 1 Y 4  triple mixed color offset sub-unit  1613 X 1 Y 4  may provide first X 1 Y 4  triple mixed color offset values RX 1 Y 40  to RX 1 Y 4255  corresponding to when the second color light emitting pixel number is 1 and the third color light emitting pixel number is 4, with respect to a target pixel of the first color. For example, the first X 1 Y 4  triple mixed color offset values RX 1 Y 40  to RX 1 Y 4255  may be determined using the following Equation 11. 
         RX 1 Y 4= RX 2 Y 4+( RX 2 Y 4− RX 3 Y 4)  Equation 11
 
     Here, RX 1 Y 4  may be a first X 1 Y 4  triple mixed color offset value corresponding to an input grayscale value, RX 2 Y 4  may be a first X 2 Y 4  triple mixed color offset value corresponding to the input grayscale value, and RX 3 Y 4  may be a first X 3 Y 4  triple mixed color offset value corresponding to the input grayscale value. 
     A first X 4 Y 1  triple mixed color offset sub-unit  1613 X 4 Y 1  may provide first X 4 Y 1  triple mixed color offset values RX 4 Y 10  to RX 4 Y 1255  corresponding to when the second color light emitting pixel number is 4 and the third color light emitting pixel number is 1, with respect to a target pixel of the first color. For example, the first X 4 Y 1  triple mixed color offset values RX 4 Y 10  to RX 4 Y 1255  may be determined using the following Equation 12. 
         RX 4 Y 1= RX 4 Y 2+( RX 4 Y 2− RX 4 Y 3)  Equation 12
 
     Here, RX 4 Y 1  may be a first X 4 Y 1  triple mixed color offset value corresponding to an input grayscale value, RX 4 Y 2  may be a first X 4 Y 2  triple mixed color offset value corresponding to the input grayscale value, and RX 4 Y 3  may be a first X 4 Y 3  triple mixed color offset value corresponding to the input grayscale value. 
       FIG. 38  illustrates a table obtained by organizing a relationship of double mixed color offset values and triple mixed color offset values, with respect to a target pixel of the first color. In accordance with the exemplary embodiment shown in  FIGS. 35 to 37 , a memory device is used only when the first single color offset values RSO 0  to RSO 255  and some double mixed color offset values RX 20  to RX 2255 , RX 40  to RX 4255 , RY 20  to RY 2255 , and RY 40  to RY 4255  are generated, and the other double mixed color offset values and the other triple mixed color offset values are produced through calculation, so that the configuration cost of the memory device can be reduced. 
       FIGS. 39 to 42  are diagrams illustrating a second double mixed color offset provider and a second triple mixed color offset provider according to an exemplary embodiment of the inventive concept. 
     Referring to  FIG. 39 , the second double mixed color offset provider  1622  may include second double mixed color offset sub-units  1622 X 1 ,  1622 X 2 ,  1622 Y 1 , and  1622 Y 2 . 
     A second X 1  double mixed color offset sub-unit  1622 X 1  may provide second X 1  double mixed color offset values GX 10  to GX 1255  corresponding to when the first color light emitting pixel number is 1 and third color light emitting pixel number is 0, with respect to a target pixel of the second color. 
     A second X 2  double mixed color offset sub-unit  1622 X 2  may provide second X 2  double mixed color offset values GX 20  to GX 2255  corresponding to when the first color light emitting pixel number is 2 and third color light emitting pixel number is 0, with respect to a target pixel of the second color. 
     A second Y 1  double mixed color offset sub-unit  1622 Y 1  may provide second Y 1  double mixed color offset values GY 10  to GY 1255  corresponding to when the first color light emitting pixel number is 0 and third color light emitting pixel number is 1, with respect to a target pixel of the second color. 
     A second Y 2  double mixed color offset sub-unit  1622 Y 2  may provide second Y 2  double mixed color offset values GY 20  to GY 2255  corresponding to when the first color light emitting pixel number is 0 and third color light emitting pixel number is 2, with respect to a target pixel of the second color. 
     Referring to  FIG. 40 , the second X 2  double mixed color offset sub-unit  1622 X 2  may include a second X 2  double mixed color reference offset provider  16221 X 2  and a second X 2  double mixed color total offset generator  16222 X 2 . 
     The second X 2  double mixed color reference offset provider  16221 X 2  may provide second X 2  double mixed color reference offset values GX 2 R 1  to GX 2 R 9  corresponding to the input maximum luminance value DBVI. 
     The second X 2  double mixed color total offset generator  16222 X 2  may generate the second X 2  double mixed color offset values GX 20  to GX 2255  by interpolating the second X 2  double mixed color reference offset values GX 2 R 1  to GX 2 R 9 . 
     A configuration and an operation of the second X 2  double mixed color offset sub-unit  1622 X 2  are substantially identical to those of the first single color offset provider  1611  shown in  FIG. 28 , and therefore, overlapping descriptions will be omitted. Likewise, the second X 1  double mixed color offset sub-unit  1622 X 1 , the second Y 1  double mixed color offset sub-unit  1622 Y 1 , and the second Y 2  double mixed color offset sub-unit  1622 Y 2  may be similarly configured, and therefore, overlapping descriptions will be omitted. 
     Referring to  FIG. 41 , the second triple mixed color offset provider  1623  may include second triple mixed color offset sub-units  1623 X 1 Y 1 ,  1623 X 1 Y 2 , and  1623 X 2 Y 1 . 
     A second X 1 Y 1  triple mixed color offset sub-unit  1623 X 1 Y 1  may provide second X 1 Y 1  triple mixed color offset values GX 1 Y 10  to GX 1 Y 1255  corresponding to when the first color light emitting pixel number is 1 and the third color light emitting pixel number is 1, with respect to a target pixel of the second color. For example, the second X 1 Y 1  triple mixed color offset values GX 1 Y 10  to GX 1 Y 1255  may be determined using the following Equation 13. 
     
       
         
           
             
               
                 
                   
                     GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                   
                   = 
                   
                     W_GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     * 
                     
                       
                         GSO 
                         + 
                         
                           GX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                       
                         
                             
                         
                         ⁢ 
                         2 
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   13 
                 
               
             
           
         
       
     
     Here, GX 1 Y 1  may be a second X 1 Y 1  triple mixed color offset value corresponding to an input grayscale value, W_GX 1 Y 1  may be a weighted value, GSO may be a second single color offset value corresponding to the input grayscale value, and GX 2 Y 2  may be a white color offset value corresponding to the input grayscale value. The weighted value W_GX 1 Y 1  may be increased as the input grayscale value is increased. The weighted value W_GX 1 Y 1  may be a real number that is 0 or more and is 1 or less. The weighted value W_GX 1 Y 1  may vary depending on the input maximum luminance value DBVI. GX 2 Y 2  may be 0. 
     A second X 1 Y 2  triple mixed color offset sub-unit  1623 X 1 Y 2  may provide second X 1 Y 2  triple mixed color offset values GX 1 Y 20  to GX 1 Y 2255  corresponding to when the first color light emitting pixel number is 1 and the third color light emitting pixel number is 2, with respect to a target pixel of the second color. For example, the second X 1 Y 2  triple mixed color offset values GX 1 Y 20  to GX 1 Y 2255  may be determined using the following Equation 14. 
     
       
         
           
             
               
                 
                   
                     GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                   
                   = 
                   
                     W_GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                     * 
                     
                       
                         
                           GY 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                         + 
                         
                           GX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                       
                         
                             
                         
                         ⁢ 
                         2 
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   14 
                 
               
             
           
         
       
     
     Here, GX 1 Y 2  may be a second X 1 Y 2  triple mixed color offset value corresponding to an input grayscale value, W_GX 1 Y 2  may be a weighted value, GY 2  may be a second Y 2  double mixed color offset value corresponding to the input grayscale value, and GX 2 Y 2  may be a white color offset value corresponding to the input grayscale value. The weighted value W_GX 1 Y 2  may be increased as the input grayscale value is increased. The weighted value W_GX 1 Y 2  may be a real number that is 0 or more and is 1 or less. The weighted value W_GX 1 Y 2  may vary depending on the input maximum luminance value DBVI. GX 2 Y 2  may be 0. 
     A second X 2 Y 1  triple mixed color offset sub-unit  1623 X 2 Y may provide second X 2 Y 1  triple mixed color offset values GX 2 Y 10  to GX 2 Y 1255  corresponding to when the first color light emitting pixel number is 2 and the third color light emitting pixel number is 1, with respect to a target pixel of the second color. For example, the second X 2 Y 1  triple mixed color offset values GX 2 Y 10  to GX 2 Y 1255  may be determined using the following Equation 15. 
     
       
         
           
             
               
                 
                   
                     GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                   
                   = 
                   
                     W_GX 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     2 
                     ⁢ 
                     Y 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                     * 
                     
                       
                         
                           GX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                         + 
                         
                           GX 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           Y 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           2 
                         
                       
                       
                         
                             
                         
                         ⁢ 
                         2 
                       
                     
                   
                 
               
               
                 
                   Equation 
                   ⁢ 
                   
                       
                   
                   ⁢ 
                   15 
                 
               
             
           
         
       
     
     Here, GX 2 Y 1  may be a second X 2 Y 1  triple mixed color offset value corresponding to an input grayscale value, W_GX 2 Y 1  may be a weighted value, GX 2  may be a second X 2  double mixed color offset value corresponding to the input grayscale value, and GX 2 Y 2  may be a white color offset value corresponding to the input grayscale value. The weighted value W_GX 2 Y 1  may be increased as the input grayscale value is increased. The weighted value W_GX 2 Y 1  may be a real number that is 0 or more and is 1 or less. The weighted value W_GX 2 Y 1  may vary depending on the input maximum luminance value DBVI. GX 2 Y 2  may be 0. 
       FIG. 42  illustrates a table obtained by organizing a relationship of double mixed color offset values and triple mixed color offset values, with respect to a target pixel of the second color. In accordance with the exemplary embodiment shown in  FIGS. 39 to 41 , a memory device is used only when the second single color offset values GSO 0  to GSO 255  and the second double mixed color offset values GX 10  to GX 1255 , GX 20  to GX 2255 , GY 10  to GY 1255 , and GY 20  to GY 2255  are generated, and the second triple mixed color offset values GX 1 Y 10  to GX 1 Y 1255 , GX 2 Y 10  to GX 2 Y 1255 , GX 1 Y 20  to GX 1 Y 2255 , and GX 2 Y 20  to GX 2 Y 2255  are produced through calculation, so that the configuration cost of the memory device can be reduced. 
       FIGS. 43 to 46  are diagrams illustrating a third double mixed color offset provider and a third triple mixed color offset provider according to an exemplary embodiment of the inventive concept. 
     Except that a target pixel is a pixel emitting light of the third color, the third double mixed color offset provider  1632  corresponds to the first double mixed color offset provider  1612  shown in  FIG. 35 , and the third triple mixed color offset provider  1633  corresponds to the third triple mixed color offset provider  1613  shown in  FIG. 37 . Therefore, overlapping descriptions will be omitted. 
     In the display device and the driving method thereof in accordance with exemplary embodiments of the inventive concept, the display device can exhibit a desired luminance even when single color light and mixed color light are emitted in addition to white color light. 
     While the inventive concept has been shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made thereto without departing from the spirit and scope of the inventive concept as set forth in the following claims.