Display device

Abstract

A display device is provided. The display device includes a display panel including a plurality of pixels, a gate driver applying a gate signal to a gate line, a data driver applying a data voltage to a data line, and a driving controller determining a display mode of the display panel as a moving image mode or a still image mode according to whether input image data is a moving image or a still image, driving the display panel at a moving image driving frequency in the moving image mode and at a still image driving frequency in the still image mode, operating the gate driver in an alternate driving mode such that the gate driver scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration, and when an image transition occurs in the still image mode, inserting a compensation frame to scan all of the gate lines.

Description

TECHNICAL FIELD

[0001] Example embodiments of the present inventive concept relate to a display apparatus and a method of driving a display apparatus. More particularly, example embodiments of the present inventive concept relate to a display apparatus alternately driving a first set of gate lines and a second set of gate lines for a static image and a method of driving a display apparatus. BACKGROUND

[0002] Generally, a display apparatus includes a display panel and a display panel driver. The display panel includes a plurality of gate lines, a plurality of data lines, a plurality of emission lines, and a plurality of pixels. The display panel driver includes a gate driver, a data driver, an emission driver, and a driving controller. The gate driver outputs a gate signal to the gate lines. The data driver outputs a data voltage to the data lines. The emission driver outputs an emission signal to the emission lines. The driving controller controls the gate driver, the data driver, and the emission driver. In addition, the display panel driver can further include a power voltage generator that applies a power voltage and an initialization voltage to the display panel.

[0003] The driving controller can determine a driving frequency of the display panel based on input image data. When the input image data represents a static image, the driving controller can drive the display panel at a relatively low driving frequency such that power consumption of the display apparatus can be reduced. When the display panel is driven at a low driving frequency, display quality of the display panel can be deteriorated due to flicker. SUMMARY

[0004] Example embodiments of the present inventive concept provide a display apparatus that prevents flicker of a display panel to enhance display quality.

[0005] Example embodiments of the present inventive concept also provide a method of driving a display apparatus.

[0006] In an exemplary embodiment of a display apparatus according to the inventive concept, the display apparatus includes a display panel, a gate driver, a data driver, and a driving controller. The display panel includes a plurality of pixels. The display panel is configured to display an image based on input image data. The gate driver is configured to apply a gate signal to gate lines of the display panel. The data driver is configured to apply a data voltage to data lines of the display panel. The driving controller is configured to determine a display mode of the display panel as a motion image mode or a still image mode according to whether the input image data is a motion image or a still image. The driving controller is configured to drive the display panel at a motion image driving frequency in the motion image mode, and is configured to drive the display panel at a still image driving frequency in the still image mode. In the still image mode, the driving controller is configured to operate the gate driver in an alternate driving mode such that the gate driver scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration. When an image transition occurs in the still image mode, the driving controller is configured to insert a compensation frame to scan all of the gate lines.

[0007] In an exemplary embodiment, a length of the first duration of the alternate driving mode can be substantially the same as a length of the second duration of the alternate driving mode.

[0008] In an exemplary embodiment, a length of the compensation frame can be substantially the same as a length of the first duration of the alternate driving mode and a length of the second duration of the alternate driving mode.

[0009] In an exemplary embodiment, the first set of gate lines can be odd-numbered gate lines. The second set of gate lines can be even-numbered gate lines.

[0010] In an exemplary embodiment, a width of a gate pulse in the first duration of the alternate driving mode can be substantially the same as a width of a gate pulse in the compensation frame.

[0011] In an exemplary embodiment, a width of a gate pulse in the first duration of the alternate driving mode can be equal to or greater than twice a width of a gate pulse in the compensation frame.

[0012] In an exemplary embodiment, in the motion image mode, the driving controller can be configured to operate the gate driver in a normal driving mode such that the gate driver scans all of the gate lines.

[0013] In an exemplary embodiment, the driving controller can include a still image determiner configured to determine whether the input image data is a moving image or a still image, a driving frequency determiner configured to determine a moving image driving frequency and a still image driving frequency, a driving mode determiner configured to determine whether a driving mode of the display panel is an alternate driving mode or a normal driving mode, and a compensation frame inserter configured to insert a compensation frame.

[0014] In an exemplary embodiment, when an image transition occurs in the still image mode, the compensation frame inserter can be configured to compare a difference between a gray value of a previous image and a gray value of a current image with a gray threshold value. When the difference between the gray value of the previous image and the gray value of the current image is greater than the gray threshold value, the compensation frame inserter can be configured to insert a compensation frame.

[0015] In an exemplary embodiment, when the still image driving frequency is equal to or greater than a frequency threshold value, the driving mode determiner can be configured to operate the gate driver in a first alternate driving mode. When the still image driving frequency is less than the frequency threshold value, the driving mode determiner can be configured to operate the gate driver in a second alternate driving mode.

[0016] In an exemplary embodiment, in the first alternate driving mode, the first group of gate lines can be odd-numbered gate lines, and the second group of gate lines can be even-numbered gate lines.

[0017] In an exemplary embodiment, in the second alternate driving mode, the gate driver scans a quarter of the gate lines in each of a first duration, a second duration, a third duration, and a fourth duration.

[0018] In an exemplary embodiment, at least one of the pixels can include a first pixel switching element including a control electrode connected to a first node, an input electrode connected to a second node, and an output electrode connected to a third node, a second pixel switching element including a control electrode to which a data write gate signal is applied, an input electrode to which a data voltage is applied, and an output electrode connected to the second node, a third pixel switching element including a control electrode to which the data write gate signal is applied, an input electrode connected to the first node, and an output electrode connected to the third node, a fourth pixel switching element including a control electrode to which a data initialization gate signal is applied, an input electrode to which an initialization voltage is applied, and an output electrode connected to the first node, a fifth pixel switching element including a control electrode to which an emission signal is applied, an input electrode to which a high power voltage is applied, and an output electrode connected to the second node, a sixth pixel switching element including a control electrode to which the emission signal is applied, an input electrode connected to the third node, and an output electrode connected to an anode of an organic light emitting element, a seventh pixel switching element including a control electrode to which the data initialization gate signal is applied, an input electrode to which the initialization voltage is applied, and an output electrode connected to the anode of the organic light emitting element, a storage capacitor including a first electrode to which the high power voltage is applied and a second electrode connected to the first node, and the organic light emitting element including the anode connected to the output electrode of the sixth pixel switching element and a cathode to which a low power voltage is applied.

[0019] In an exemplary embodiment of a method of driving a display apparatus, the method includes determining whether input image data is a moving image or a still image, determining a moving image driving frequency for a moving image mode and a still image driving frequency for a still image mode, operating a gate driver in an alternate driving mode such that the gate driver uniquely scans a first set of gate lines in a first duration and uniquely scans a second set of gate lines in a second duration, and inserting a compensation frame to scan all of the gate lines when an image transition occurs in the still image mode.

[0020] In an exemplary embodiment, a length of the first duration of the alternate driving mode can be substantially the same as a length of the second duration of the alternate driving mode.

[0021] In an exemplary embodiment, a length of the compensation frame can be substantially the same as the length of the first duration of the alternate driving mode and the length of the second duration of the alternate driving mode.

[0022] In an exemplary embodiment, in the moving image mode, the gate driver can be operated in a normal driving mode such that the gate driver scans all of the gate lines.

[0023] In an exemplary embodiment, the inserting the compensation frame can include comparing a difference between a gray value of a previous image and a gray value of a current image with a gray threshold when an image transition occurs in the still image mode, and inserting the compensation frame when the difference between the gray value of the previous image and the gray value of the current image is greater than the gray threshold.

[0024] In an exemplary embodiment, when the still image driving frequency is equal to or greater than a frequency threshold, the gate driver can operate in a first alternate driving mode. When the still image driving frequency is less than the frequency threshold, the gate driver can operate in a second alternate driving mode.

[0025] In an exemplary embodiment, in the first alternate driving mode, the gate driver can uniquely scan odd-numbered gate lines in a first duration and uniquely scan even-numbered gate lines in a second duration, and wherein, in the second alternate driving mode, the gate driver uniquely scans one fourth of the gate lines in each of a first duration, a second duration, a third duration, and a fourth duration.

[0026] According to the display apparatus and the method of driving the display apparatus, the driving controller drives the display panel at a motion image driving frequency in a motion image mode, and drives the display panel at a still image driving frequency in a still image mode. Accordingly, power consumption of the display apparatus can be reduced.

[0027] In addition, in the still image mode, the driving controller can operate the gate driver in an alternate driving mode such that the gate driver scans a first group of gate lines in a first duration and scans a second group of gate lines in a second duration. Accordingly, flicker due to current leakage of the pixels can be prevented. In addition, when an image transition occurs in the still image mode, the driving controller can insert a compensation frame to scan all of the gate lines such that flicker due to a luminance difference between a first frame and a second frame after the image transition in the still image mode can be prevented. Accordingly, display quality of the display panel can be enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0028] The above and other features and advantages of the inventive concept will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

[0029] Figure 1 is a block diagram illustrating a display apparatus according to an exemplary embodiment of the inventive concept;

[0030] Figure 2 is a circuit diagram illustrating a pixel of the display panel of Figure 1

[0031] Figure 3 ​is a timing chart showing input signals applied to Figure 2 pixels of

[0032] Figure 4 is a graph showing a decrease in luminance due to current leakage of the pixels of Figure 2 at a first driving frequency;

[0033] Figure 5 is a graph showing a decrease in luminance due to current leakage of the pixels of Figure 2 at a second driving frequency;

[0034] Figure 6 is a block diagram showing a driving controller of Figure 1 ;

[0035] Figure 7 is a flowchart showing an operation of the driving controller of Figure 1 ;

[0036] Figure 8 is a timing chart showing an operation of a gate driver of Figure 1 in a compensation frame;

[0037] Figure 9 is a timing chart showing an operation of a gate driver of Figure 1 in a first duration of an alternate driving mode;

[0038] Figure 10 is a timing chart showing an operation of a gate driver of Figure 1 in a second duration of an alternate driving mode;

[0039] Figure 11 is a graph showing luminance of a display panel of Figure 1 in an alternate driving mode;

[0040] Figure 12 is a graph showing luminance of a display panel of Figure 1 when an image transition occurs in a static image mode and no compensation frame is inserted;

[0041] Figure 13 is a graph showing luminance of a display panel of Figure 1 when an image transition occurs in a static image mode and a compensation frame is inserted;

[0042] Figure 14 is a timing chart showing an operation of a gate driver of a display device according to an exemplary embodiment of the inventive concept in a compensation frame;

[0043] Figure 15 is a timing chart showing an operation of a gate driver in a first duration of an alternate driving mode;

[0044] Figure 16 is a timing chart illustrating an operation of the gate driver in the second duration of the alternate driving mode;

[0045] Figure 17 is a timing chart illustrating an operation of the gate driver of the display apparatus according to an exemplary embodiment of the inventive concept in a compensation frame;

[0046] Figure 18 is a timing chart illustrating an operation of the gate driver in the first duration of the alternate driving mode;

[0047] Figure 19 is a timing chart illustrating an operation of the gate driver in the second duration of the alternate driving mode;

[0048] Figure 20 is a flowchart illustrating an operation of the drive controller of the display apparatus according to an exemplary embodiment of the inventive concept;

[0049] Figure 21 is a flowchart illustrating an operation of the drive controller of the display apparatus according to an exemplary embodiment of the inventive concept;

[0050] Figure 22 is a graph illustrating a luminance of the display panel of the display apparatus in the first alternate driving mode; and

[0051] Figure 23 is a graph illustrating a luminance of the display panel of the display apparatus in the second alternate driving mode. DETAILED DESCRIPTION

[0052] Hereinafter, the inventive concept will be explained in detail with reference to the accompanying drawings.

[0053] Figure 1 is a block diagram of a display apparatus according to an exemplary embodiment of the inventive concept.

[0054] Referring to FIG. 1, Figure 1 The display apparatus includes a display panel 100 and a display panel driver. The display panel driver includes a drive controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power supply voltage generator 700.

[0055] The driving controller 200 and the data driver 500 can be integrally formed in one integrated circuit chip (IC chip). The driving controller 200, the data driver 500, and the power voltage generator 700 can be integrally formed in one IC chip. The driving controller 200, the gamma reference voltage generator 400, and the data driver 500 can be integrally formed in one IC chip. The driving controller 200, the gate driver 300, the gamma reference voltage generator 400, and the data driver 500 can be integrally formed in one IC chip. The driving controller 200, the gate driver 300, the gamma reference voltage generator 400, the data driver 500, and the emission driver 600 can be integrally formed in one IC chip. The driving controller 200, the gate driver 300, the gamma reference voltage generator 400, the data driver 500, the emission driver 600, and the power voltage generator 700 can be integrally formed in one IC chip.

[0056] The display panel 100 includes a plurality of gate lines GWL, GIL, and GBL, a plurality of data lines DL, a plurality of emission lines EL, and a plurality of pixels electrically connected to the gate lines GWL, GIL, and GBL, the data lines DL, and the emission lines EL. The gate lines GWL, GIL, and GBL extend in a first direction D1, the data lines DL extend in a second direction D2 crossing the first direction D1, and the emission lines EL extend in the first direction D1.

[0057] The driving controller 200 receives input image data IMG and input control signals CONT from an external device. The input image data IMG can include red image data, green image data, and blue image data. The input image data IMG can include white image data. The input image data IMG can include magenta image data, cyan image data, and yellow image data. The input control signals CONT can include a main clock signal and a data enable signal. The input control signals CONT can further include a vertical synchronization signal and a horizontal synchronization signal.

[0058] The driving controller 200 generates a first control signal CONT1, a second control signal CONT2, a third control signal CONT3, a fourth control signal CONT4, and a data signal DATA based on the input image data IMG and the input control signals CONT.

[0059] The driving controller 200 generates the first control signal CONT1 for controlling the operation of the gate driver 300 based on the input control signals CONT, and outputs the first control signal CONT1 to the gate driver 300. The first control signal CONT1 can include a vertical start signal and a gate clock signal.

[0060] The drive controller 200 generates a second control signal CONT2 for controlling the operation of the data driver 500 based on the input control signal CONT, and outputs the second control signal CONT2 to the data driver 500. The second control signal CONT2 can include a horizontal start signal and a load signal.

[0061] The drive controller 200 generates a data signal DATA based on the input image data IMG. The drive controller 200 outputs the data signal DATA to the data driver 500.

[0062] The drive controller 200 generates a third control signal CONT3 for controlling the operation of the gamma reference voltage generator 400 based on the input control signal CONT, and outputs the third control signal CONT3 to the gamma reference voltage generator 400.

[0063] The drive controller 200 generates a fourth control signal CONT4 for controlling the operation of the emission driver 600 based on the input control signal CONT, and outputs the fourth control signal CONT4 to the emission driver 600.

[0064] The gate driver 300 generates gate signals for driving the gate lines GWL, GIL, and GBL in response to the first control signal CONT1 received from the drive controller 200. The gate driver 300 can sequentially output the gate signals to the gate lines GWL, GIL, and GBL. For example, the gate driver 300 can be directly formed on the display panel 100. For example, the gate driver 300 can be integrated on the display panel 100.

[0065] The gamma reference voltage generator 400 generates a gamma reference voltage VGREF in response to the third control signal CONT3 received from the drive controller 200. The gamma reference voltage generator 400 provides the gamma reference voltage VGREF to the data driver 500. The gamma reference voltage VGREF has a value corresponding to a level of the data signal DATA.

[0066] In an exemplary embodiment, the gamma reference voltage generator 400 can be embedded in the drive controller 200 or in the data driver 500.

[0067] The data driver 500 receives the second control signal CONT2 and the data signal DATA from the drive controller 200, and receives the gamma reference voltage VGREF from the gamma reference voltage generator 400. The data driver 500 converts the data signal DATA into a data voltage having an analog type using the gamma reference voltage VGREF. The data driver 500 outputs the data voltage to the data line DL.

[0068] The transmitter driver 600 generates a transmit signal to drive the transmitter line EL in response to a fourth control signal CONT4 received from the drive controller 200. The transmitter driver 600 can output the transmit signal to the transmitter line EL.

[0069] The power supply voltage generator 700 generates power supply voltages for operating the display panel 100 and the display panel driver. For example, the power supply voltage generator 700 can output a high power supply voltage ELVDD to the pixel circuitry of the display panel 100. The power supply voltage generator 700 can output a low power supply voltage ELVSS to the pixel circuitry of the display panel 100. The power supply voltage generator 700 can output an initialization voltage VI to the pixel circuitry of the display panel 100.

[0070] Figure 2 It is shown Figure 1 Circuit diagram of a display panel with 100 pixels. Figure 3 It shows that it is applied to Figure 2 The timing diagram of the input signal of the pixel.

[0071] Reference Figures 1 to 3 The display panel 100 includes multiple pixels. Each pixel includes an organic light-emitting element (OLED).

[0072] The pixel receives a data write gate signal GW, a data initialization gate signal GI, an organic light-emitting element (OLED) initialization gate signal, a data voltage VDATA, and an emission signal EM. The OLED of the pixel emits light corresponding to the level of the data voltage VDATA to display an image. In this exemplary embodiment, the OLED initialization gate signal may be the same as the data initialization gate signal GI.

[0073] At least one of the pixels may include a first pixel switching element T1 to a seventh pixel switching element T7, a storage capacitor CST, and an organic light-emitting element OLED.

[0074] The first pixel switching element T1 includes a control electrode connected to a first node N1, an input electrode connected to a second node N2, and an output electrode connected to a third node N3. The first pixel switching element T1 may be a P-type thin-film transistor. The control electrode of the first pixel switching element T1 may be a gate electrode, the input electrode of the first pixel switching element T1 may be a source electrode, and the output electrode of the first pixel switching element T1 may be a drain electrode.

[0075] The second pixel switching element T2 includes a control electrode to which a data write gate signal GW is applied, an input electrode to which a data voltage VDATA is applied, and an output electrode connected to the second node N2. The second pixel switching element T2 may be a P-type thin-film transistor. The control electrode of the second pixel switching element T2 may be a gate electrode, the input electrode of the second pixel switching element T2 may be a source electrode, and the output electrode of the second pixel switching element T2 may be a drain electrode.

[0076] The third pixel switching elements T3-1 and T3-2 include a control electrode to which a data write gate signal GW is applied, an input electrode connected to the first node N1, and an output electrode connected to the third node N3. The third pixel switching elements T3-1 and T3-2 can be P-type thin-film transistors. The control electrode of the third pixel switching elements T3-1 and T3-2 can be a gate electrode, the input electrode of the third pixel switching elements T3-1 and T3-2 can be a source electrode, and the output electrode of the third pixel switching elements T3-1 and T3-2 can be a drain electrode.

[0077] like Figure 2 As shown, for example, the third pixel switching element may include two pixel switching elements T3-1 and T3-2 connected in series with each other. Figure 2 Unlike other switches, the third pixel switching element can be configured as a single switching element.

[0078] The fourth pixel switching elements T4-1 and T4-2 include a control electrode to which a data initialization gate signal GI is applied, an input electrode to which an initialization voltage VI is applied, and an output electrode connected to the first node N1. The fourth pixel switching elements T4-1 and T4-2 can be P-type thin-film transistors. The control electrode of the fourth pixel switching elements T4-1 and T4-2 can be a gate electrode, the input electrode of the fourth pixel switching elements T4-1 and T4-2 can be a source electrode, and the output electrode of the fourth pixel switching elements T4-1 and T4-2 can be a drain electrode.

[0079] like Figure 2 As shown, for example, the fourth pixel switching element may include two pixel switching elements T4-1 and T4-2 connected in series with each other. Figure 2 Unlike other switches, the fourth pixel switching element can be configured as a single switching element.

[0080] The fifth pixel switching element T5 includes a control electrode to which a transmission signal EM is applied, an input electrode to which a high power supply voltage ELVDD is applied, and an output electrode connected to the second node N2.

[0081] The fifth pixel switching element T5 can be a P-type thin-film transistor. The control electrode of the fifth pixel switching element T5 can be the gate electrode, the input electrode of the fifth pixel switching element T5 can be the source electrode, and the output electrode of the fifth pixel switching element T5 can be the drain electrode.

[0082] The sixth pixel switching element T6 includes a control electrode to which the emission signal EM is applied, an input electrode connected to the third node N3, and an output electrode connected to the anode of the organic light emitting element OLED.

[0083] The sixth pixel switching element T6 can be a P-type thin film transistor. The control electrode of the sixth pixel switching element T6 can be a gate electrode, the input electrode of the sixth pixel switching element T6 can be a source electrode, and the output electrode of the sixth pixel switching element T6 can be a drain electrode.

[0084] The seventh pixel switching element T7 includes a control electrode to which the organic light emitting element initialization gate signal GI is applied, an input electrode to which the initialization voltage VI is applied, and an output electrode connected to the anode of the organic light emitting element OLED.

[0085] The seventh pixel switching element T7 can be a P-type thin film transistor. The control electrode of the seventh pixel switching element T7 can be a gate electrode, the input electrode of the seventh pixel switching element T7 can be a source electrode, and the output electrode of the seventh pixel switching element T7 can be a drain electrode.

[0086] The storage capacitor CST includes a first electrode to which the high power supply voltage ELVDD is applied and a second electrode connected to the first node N1.

[0087] The organic light emitting element OLED includes an anode connected to the output electrode of the sixth pixel switching element T6 and a cathode to which the low power supply voltage ELVSS is applied.

[0088] In the period of the first duration DU1, the first node N1 and the storage capacitor CST are initialized in response to the data initialization gate signal GI[N] in the pixel arranged in the Nth row. Figure 3 In the period of the first duration DU1, the anode of the organic light emitting element OLED is initialized in response to the organic light emitting element initialization gate signal GI[N] in the pixel arranged in the Nth row. In the period of the second duration DU2, the threshold voltage |VTH| of the first pixel switching element T1 is compensated and the data voltage VDATA whose threshold voltage |VTH| is compensated is written to the storage capacitor CST in response to the data write gate signal GW[N]. The organic light emitting element OLED emits light in response to the emission signal EM[N] in the period after the fourth duration DU4, the fifth duration DU5, and the fifth duration DU5, so that the pixel in the Nth row displays an image.

[0089] In the pixel arranged in the (N+1)th row, during the second duration DU2, the first node N1 and the storage capacitor CST are initialized in response to the data initialization gate signal GI[N+1]. During the second duration DU2, the anode of the organic light emitting element OLED is initialized in response to the organic light emitting element initialization gate signal GI[N+1]. During the third duration DU3, the threshold voltage |VTH| of the first pixel switching element T1 is compensated and the data voltage VDATA with the threshold voltage |VTH| compensated is written to the storage capacitor CST in response to the data write gate signal GW[N+1]. During the fifth duration DU5 and the period after the fifth duration DU5, the organic light emitting element OLED emits light in response to the emission signal EM[N+1] so that the pixel in the (N+1)th row displays an image.

[0090] In the pixel arranged in the Nth row, during the first duration DU1, the data initialization gate signal GI[N] can have an active level. For example, the active level of the data initialization gate signal GI[N] can be a low level. When the data initialization gate signal GI[N] has the active level, the fourth pixel switching elements T4-1 and T4-2 of the pixel of the Nth row are turned on so that the initialization voltage VI can be applied to the first node N1.

[0091] During the first duration DU1, the organic light emitting element initialization gate signal GI[N] can have an active level. In the present exemplary embodiment, the organic light emitting element initialization gate signal GI[N] can be the same as the data initialization gate signal GI[N]. When the organic light emitting element initialization gate signal GI[N] has the active level, the seventh pixel switching element T7 of the pixel of the Nth row is turned on so that the initialization voltage VI can be applied to the anode of the organic light emitting element OLED to initialize the organic light emitting element OLED.

[0092] In the pixel arranged in the Nth row, during the second duration DU2, the data write gate signal GW[N] can have an active level. For example, the active level of the data write gate signal GW[N] can be a low level. When the data write gate signal GW[N] has the active level, the second pixel switching element T2 and the third pixel switching elements T3-1 and T3-2 of the pixel of the Nth row are turned on. In addition, the first pixel switching element T1 of the pixel of the Nth row is turned on in response to the initialization voltage VI stored in the storage capacitor CST.

[0093] A voltage of the absolute value |VTH| of the threshold voltage of the first pixel switching element T1 subtracted from the data voltage VDATA can be charged at the storage capacitor CST of the pixel of the Nth row along a path generated through the first pixel switching element T1, the second pixel switching element T2, and the third pixel switching elements T3-1 and T3-2.

[0094] During the fourth duration DU4 and the fifth duration DU5, the emission signal EM[N] corresponding to the Nth row can have an active level. The active level of the emission signal EM[N] can be a low level. When the emission signal EM[N] has the active level, the fifth pixel switching element T5 and the sixth pixel switching element T6 of the pixel of the Nth row are turned on. In addition, the first pixel switching element T1 of the pixel of the Nth row is turned on by the threshold voltage-compensated data voltage stored in the storage capacitor CST.

[0095] Figure 4 is a graph showing a reduction in luminance of the pixel of Figure 2 due to current leakage at the first driving frequency. Figure 5 is a graph showing a reduction in luminance of the pixel of Figure 2 due to current leakage at the second driving frequency.

[0096] Referring to Figures 1 to 5 , the driving controller 200 can determine whether a display mode of the display panel 100 is a moving image mode or a still image mode according to the input image data IMG. In the moving image mode, the driving controller 200 can drive the display panel 100 at a moving image driving frequency. In the still image mode, the driving controller 200 can drive the display panel 100 at a still image driving frequency.

[0097] For example, the moving image driving frequency can be 60 Hz. Alternatively, the moving image driving frequency can be 120 Hz or 240 Hz. The still image driving frequency can be equal to or less than the moving image driving frequency. The driving controller 200 can appropriately determine the still image driving frequency according to the input image data IMG.

[0098] For example, Figure 4 the driving frequency in Figure 5 may be 30 Hz. Current of the pixel can leak through the third pixel switching elements T3-1 and T3-2 and the fourth pixel switching elements T4-1 and T4-2. Due to the current leakage of the pixel, luminance of the display panel 100 can be reduced. In Figure 4 , the driving frequency is relatively high, and thus the data voltage VDATA is refreshed at a high frequency, so that the reduction in luminance due to the current leakage can be relatively small. For example, due to Figure 4Due to the current leakage, the luminance of the display panel 100 can decrease from the first luminance LI to a second luminance L2. In contrast, in Figure 5 In the case of the motion image mode, the driving frequency is relatively high, and thus the data voltage VDATA is refreshed at a high frequency, so that the decrease in luminance due to the current leakage can be relatively small. For example, in Figure 5 In the case of the motion image mode, the driving frequency is relatively high, and thus the data voltage VDATA is refreshed at a high frequency, so that the decrease in luminance due to the current leakage can be relatively small. For example, in Figure 5 The decrease in luminance in the case of the motion image mode can generate flicker.

[0099] In the period when the pixel emits light, the voltages of the fourth node N4 and the fifth node N5 float, so that the voltages of the fourth node N4 and the fifth node N5 can almost reach the high level of the gate signal, and thus the leakage current can flow in the direction from the third pixel switching elements T3-1 and T3-2 and the fourth pixel switching elements T4-1 and T4-2 to the storage capacitor CST.

[0100] Figure 6 is a block diagram illustrating the driving controller 200 of Figure 1 is a block diagram illustrating the driving controller 200 of Figure 7 is a flowchart illustrating the operation of the driving controller 200 of Figure 1 is a flowchart illustrating the operation of the driving controller 200 of Figure 8 is a timing chart illustrating the operation of the gate driver 300 in the compensation frame of Figure 1 is a timing chart illustrating the operation of the gate driver 300 in the first duration of the alternate driving mode of Figure 9 is a timing chart illustrating the operation of the gate driver 300 in the second duration of the alternate driving mode of Figure 1 is a timing chart illustrating the operation of the gate driver 300 in the second duration of the alternate driving mode of Figure 10 is a timing chart illustrating the operation of the gate driver 300 in the second duration of the alternate driving mode of Figure 1 is a timing chart illustrating the operation of the gate driver 300 in the second duration of the alternate driving mode of

[0101] Referring to Figures 1 to 10 The driving controller 200 can determine whether the display mode of the display panel 100 is the motion image mode or the static image mode according to the input image data IMG. In the motion image mode, the driving controller 200 can drive the display panel 100 at a motion image driving frequency. In the static image mode, the driving controller 200 can drive the display panel 100 at a static image driving frequency.

[0102] For example, in the static image mode, the driving controller 200 can operate the gate driver 300 in the alternate driving mode such that the gate driver 300 scans the first set of gate lines in the first duration and scans the second set of gate lines in the second duration. In addition, when an image transition occurs in the static image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines.

[0103] In contrast, in the moving image mode, the driving controller 200 can operate the gate driver 300 in the normal driving mode such that the gate driver 300 scans all the gate lines.

[0104] For example, the driving controller 200 can include a still image determiner 220 that determines whether the input image data IMG is a still image or a moving image, a driving frequency determiner 240 that determines a moving image driving frequency and a still image driving frequency, a driving mode determiner 260 that determines an alternate driving mode and a normal driving mode, and a compensation frame inserter 280 that inserts a compensation frame.

[0105] As shown in FIG. 1, Figure 7 The still image determiner 220 can determine whether the input image data IMG is a still image or a moving image (operation S100). For example, the still image determiner 220 compares images of adjacent frames of the input image data IMG for each frame to determine whether the input image data IMG is a still image or a moving image. For example, the still image determiner 220 can compare images of a plurality of frames to determine whether the input image data IMG is a still image or a moving image.

[0106] In the still image mode, the driving frequency determiner 240 can determine a still image driving frequency (operation S200). The driving frequency determiner 240 can determine the still image driving frequency based on a gray value of the input image data IMG. The driving frequency determiner 240 can determine the still image driving frequency as 30 Hz, 15 Hz, 10 Hz, 5 Hz, 1 Hz, etc.

[0107] The driving mode determiner 260 can determine whether the driving mode of the display panel 100 is the alternate driving mode or the normal driving mode. For example, when the input image data IMG is a still image, the gate driver 300 can operate in the alternate driving mode such that the gate driver 300 scans a first group of gate lines in a first duration and scans a second group of gate lines in a second duration. For example, in the alternate driving mode, a length of the first duration can be substantially the same as a length of the second duration.

[0108] When an image transition occurs in the still image mode, the compensation frame inserter 280 can insert a compensation frame to scan all the gate lines (operation S300). After the compensation frame is inserted, the gate driver 300 can operate in the alternate driving mode (operation S400). A length of the compensation frame can be substantially the same as a length of the first duration of the alternate driving mode and a length of the second duration of the alternate driving mode.

[0109] In the present exemplary embodiment, the first group of gate lines can be odd-numbered gate lines, and the second group of gate lines can be even-numbered gate lines.

[0110] For example, when an image transition occurs in the still image mode, all of the gate lines can be scanned in a first frame. In a second frame, odd-numbered gate lines can be scanned. In a third frame, even-numbered gate lines can be scanned. In a fourth frame, odd-numbered gate lines can be scanned. In a fifth frame, even-numbered gate lines can be scanned.

[0111] When an image transition occurs again in the still image mode, all of the gate lines can be scanned in a first frame of the image transition. In a second frame from the image transition, odd-numbered gate lines can be scanned. In a third frame from the image transition, even-numbered gate lines can be scanned.

[0112] In the moving image mode, the driving frequency determiner 240 can determine a moving image driving frequency (operation S500). The moving image driving frequency can be a predetermined fixed frequency. For example, the moving image driving frequency can be substantially the same as an input frequency of the input image data IMG.

[0113] In the moving image mode, the driving controller 200 can operate the gate driver 300 in a normal driving mode to scan all of the gate lines (operation S600).

[0114] Although only the data write gate signal GW among the gate signals is shown for convenience of explanation in Figures 8 to 10 , the data initialization gate signal GI, the organic light emitting element initialization gate signal, and the emission signal EM can have a timing corresponding to the data write gate signal GW.

[0115] As shown in Figure 8 , in the compensation frame, all of the gate lines can be scanned by the data write gate signals GW[1], GW[2], GW[3], GW[4], …, GW[M-1], and GW[M].

[0116] As shown in Figure 9 , in the first duration of the alternate driving mode, odd-numbered gate lines can be scanned by odd-numbered data write gate signals GW[1], GW[3], …, GW[M-1]. Herein, M can be an even number.

[0117] As shown in Figure 10 , in the second duration of the alternate driving mode, even-numbered gate lines can be scanned by even-numbered data write gate signals GW[2], GW[4], …, GW[M].

[0118] In the present exemplary embodiment, the width of the gate pulse in the first duration of the alternate driving mode can be substantially the same as the width of the gate pulse in the compensation frame. In the same manner, the width of the gate pulse in the second duration of the alternate driving mode can be substantially the same as the width of the gate pulse in the compensation frame.

[0119] In the normal driving mode, all of the gate lines can be scanned by the data write gate signals GW[1], GW[2], GW[3], GW[4], …, GW[M-1], and GW[M]. Thus, the scanning method in the normal driving mode is substantially the same as the scanning method shown in Figure 8

[0120] Figure 11 is a graph showing the luminance of the display panel 100 of Figure 1 in the alternate driving mode.

[0121] Referring to Figures 1 to 11 , in the alternate driving mode, the odd-numbered (ODD) gate lines are scanned during the first duration (e.g., F1 and F3) so that the threshold voltage-compensated data voltage is written into the pixels connected to the odd-numbered (ODD) gate lines. In addition, in the alternate driving mode, the even-numbered (EVEN) gate lines are scanned during the second duration (e.g., F2 and F4) so that the threshold voltage-compensated data voltage is written into the pixels connected to the even-numbered (EVEN) gate lines.

[0122] The user can recognize the average luminance L(AVG) of the luminance L(ODD) of the pixels connected to the odd-numbered gate lines and the luminance L(EVEN) of the pixels connected to the even-numbered gate lines so that the luminance L(AVG) displayed to the user can increase in the alternate driving mode compared to the normal driving mode. Thus, by driving the display panel 100 in the alternate driving mode, flicker can be prevented in the static image mode (low frequency driving mode).

[0123] Figure 12 is a graph showing the luminance of the display panel 100 of Figure 1 when the image transition occurs in the static image mode and the compensation frame is not inserted. Figure 13 is a graph showing the luminance of the display panel 100 of Figure 1 when the image transition occurs in the static image mode and the compensation frame is inserted.

[0124] ​For convenience of explanation, for example, the display panel 100 can operate in a static image mode during F1 duration to F6 duration. The display panel 100 can display a first image during F1 duration to F3 duration, and the display panel 100 can display a second image during F4 duration to F6 duration.

[0125] As Figure 12 As shown in FIG. 4B, when an image transition occurs in the static image mode and a compensation frame is not inserted, a changed image can be applied to pixels connected to gate lines numbered with odd numbers in F4 duration. Accordingly, the display panel 100 can represent a brightness higher than a desired brightness. When a changed image is applied to pixels connected to gate lines numbered with even numbers in F5 duration, the display panel 100 can represent a desired brightness. As explained above, when an image transition occurs in the static image mode and a compensation frame is not inserted, flicker can occur due to a difference in brightness of F4 duration and brightness of F5 duration.

[0126] As Figure 13 As shown in FIG. 4C, when an image transition occurs in the static image mode and a compensation frame is inserted, the display panel 100 can represent a desired brightness in F4 duration. In F5 duration, an image is applied only to pixels connected to gate lines numbered with odd numbers. In F6 duration, an image is applied only to pixels connected to gate lines numbered with even numbers. Accordingly, power consumption can be appropriately reduced. As explained above, when an image transition occurs in the static image mode and a compensation frame (COMP) is inserted, flicker can be prevented. From a second frame after the image transition, the display panel 100 operates in an alternate driving mode, so that flicker can be prevented and power consumption can be reduced.

[0127] According to the present exemplary embodiment, the driving controller 200 drives the display panel 100 at a moving image driving frequency in a moving image mode, and the driving controller 200 drives the display panel 100 at a static image driving frequency in a static image mode. Accordingly, power consumption of the display apparatus can be reduced.

[0128] In addition, in the static image mode, the driving controller 200 can operate the gate driver 300 in an alternate driving mode, so that the gate driver 300 scans a first group of gate lines in a first duration, and scans a second group of gate lines in a second duration. Accordingly, flicker due to current leakage of pixels can be prevented. In addition, when an image transition occurs in the static image mode, the driving controller 200 can insert a compensation frame to scan all gate lines, so that flicker due to a difference in brightness between a first frame and a second frame after the image transition in the static image mode can be prevented. Accordingly, display quality of the display panel 100 can be enhanced.

[0129] Figure 14is a timing chart illustrating an operation of a gate driver of a display apparatus according to an exemplary embodiment of the present inventive concept in a compensation frame. Figure 15 is a timing chart illustrating an operation of the gate driver in a first duration of the alternate driving mode. Figure 16 is a timing chart illustrating an operation of the gate driver in a second duration of the alternate driving mode.

[0130] The display apparatus and the method of driving the display apparatus according to the present exemplary embodiment are substantially the same as the display apparatus and the method of driving the display apparatus explained with reference to the Figures 1 to 13 The display apparatus and the method of driving the display apparatus explained in the previous exemplary embodiment are substantially the same as the display apparatus and the method of driving the display apparatus explained with reference to Figures 1 to 13 Therefore, the same reference numerals will be used to refer to the parts that are the same or similar to those described in the previous exemplary embodiment, and any repeated explanation about the above elements will be omitted.

[0131] Referring to Figures 1 to 7 and Figures 11 to 16 , the display apparatus includes a display panel 100 and a display panel driver. The display panel driver includes a driving controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power voltage generator 700.

[0132] The driving controller 200 can determine whether a display mode of the display panel 100 is a moving image mode or a still image mode according to input image data IMG. In the moving image mode, the driving controller 200 can drive the display panel 100 at a moving image driving frequency. In the still image mode, the driving controller 200 can drive the display panel 100 at a still image driving frequency.

[0133] For example, in the still image mode, the driving controller 200 can operate the gate driver 300 in an alternate driving mode such that the gate driver 300 scans a first group of gate lines in a first duration and scans a second group of gate lines in a second duration. In addition, when an image transition occurs in the still image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines.

[0134] Although only a data write gate signal GW among gate signals is illustrated for convenience of explanation in Figures 14 to 16 , a data initialization gate signal GI, an organic light emitting element initialization gate signal, and an emission signal EM can have a timing corresponding to the data write gate signal GW.

[0135] As Figure 14As shown in FIG. 6, all of the gate lines can be scanned in the compensation frame by the data write gate signals GW[1], GW[2], GW[3], GW[4], …, GW[M-1], and GW[M].

[0136] As shown in FIG. 7, in the first duration of the alternate driving mode, the odd-numbered gate lines can be scanned by the odd-numbered data write gate signals GW[1], GW[3], …, GW[M-1]. In this context, M can be an even number. Figure 15 As shown in FIG. 8, in the second duration of the alternate driving mode, the even-numbered gate lines can be scanned by the even-numbered data write gate signals GW[2], GW[4], …, GW[M].

[0137] Figure 16 As shown in FIG. 9, in the first duration of the alternate driving mode, the odd-numbered gate lines can be scanned by the odd-numbered data write gate signals GW[1], GW[3], …, GW[M-1]. In this context, M can be an even number.

[0138] In the present exemplary embodiment, the width of the gate pulse in the first duration of the alternate driving mode can be greater than the width of the gate pulse in the compensation frame. For example, the width of the gate pulse in the first duration of the alternate driving mode can be equal to or greater than twice the width of the gate pulse in the compensation frame. In the same manner, the width of the gate pulse in the second duration of the alternate driving mode can be greater than the width of the gate pulse in the compensation frame. For example, the width of the gate pulse in the second duration of the alternate driving mode can be equal to or greater than twice the width of the gate pulse in the compensation frame.

[0139] All of the gate lines are scanned in the compensation frame. However, only half of the gate lines are scanned in each of the first and second durations of the alternate driving mode, so that the width of the gate pulse can be increased in the alternate driving mode to increase the charging time of the pixels.

[0140] According to the present exemplary embodiment, the driving controller 200 drives the display panel 100 at a moving image driving frequency in the moving image mode, and the driving controller 200 drives the display panel 100 at a still image driving frequency in the still image mode. Accordingly, the power consumption of the display apparatus can be reduced.

[0141] In addition, in the still image mode, the driving controller 200 can operate the gate driver 300 in the alternate driving mode so that the gate driver 300 scans the first group of gate lines in the first duration and scans the second group of gate lines in the second duration. Accordingly, flicker due to current leakage of the pixels can be prevented. In addition, when an image transition occurs in the still image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines, so that flicker due to a difference in brightness between a first frame and a second frame after the image transition in the still image mode can be prevented. Accordingly, the display quality of the display panel 100 can be enhanced. ​

[0142] Figure 17 is a timing chart illustrating an operation of a gate driver of a display apparatus according to an exemplary embodiment of the present inventive concept in a compensation frame. Figure 18 is a timing chart illustrating an operation of the gate driver in a first duration of an alternate driving mode. Figure 19 is a timing chart illustrating an operation of the gate driver in a second duration of the alternate driving mode.

[0143] The display apparatus and the method of driving the display apparatus according to the present exemplary embodiment are substantially the same as the display apparatus and the method of driving the display apparatus explained with reference to the previous exemplary embodiments except for the waveform of the gate signal in the alternate driving mode. Figures 1 to 13 The display apparatus and the method of driving the display apparatus according to the present exemplary embodiment are substantially the same as the display apparatus and the method of driving the display apparatus explained with reference to the previous exemplary embodiments except for the waveform of the gate signal in the alternate driving mode. Figures 1 to 13 Therefore, the same reference numerals will be used to refer to the parts that are the same or similar to those described in the previous exemplary embodiments of the present inventive concept, and any repeated explanation about the above elements will be omitted.

[0144] Referring to Figures 1 to 7 , Figures 11 to 13 and Figures 17 to 19 , the display apparatus includes a display panel 100 and a display panel driver. The display panel driver includes a driving controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power supply voltage generator 700.

[0145] The driving controller 200 can determine whether a display mode of the display panel 100 is a moving image mode or a still image mode according to input image data IMG. In the moving image mode, the driving controller 200 can drive the display panel 100 at a moving image driving frequency. In the still image mode, the driving controller 200 can drive the display panel 100 at a still image driving frequency.

[0146] For example, in the still image mode, the driving controller 200 can operate the gate driver 300 in an alternate driving mode such that the gate driver 300 scans a first group of gate lines in a first duration and scans a second group of gate lines in a second duration. In addition, when an image transition occurs in the still image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines.

[0147] Although only the data write gate signal GW among the gate signals is illustrated for convenience of explanation in Figures 17 to 19 , the data initialization gate signal GI, the organic light emitting element initialization gate signal, and the emission signal EM can have a timing corresponding to the data write gate signal GW.

[0148] As Figure 17As shown in FIG. 1, all of the gate lines can be scanned by the data write gate signals GW[1], GW[2], GW[3], GW[4], …, GW[M-1], and GW[M] in the compensation frame.

[0149] As shown in FIG. 1, all of the gate lines can be scanned by the data write gate signals GW[1], GW[2], GW[3], GW[4], …, GW[M-1], and GW[M] in the compensation frame. Figure 18 As shown in FIG. 2, in the first duration of the alternate driving mode, the odd-numbered gate lines can be scanned by the odd-numbered data write gate signals GW[1], GW[3], …, GW[M-1]. In this exemplary embodiment, M can be an even number. In this exemplary embodiment, the pulse of the first data write gate signal GW[1] can be positioned in the first horizontal period of the frame. In this exemplary embodiment, the pulse of the third data write gate signal GW[3] can be positioned in the third horizontal period of the frame. Figure 9 Unlike the first data write gate signal GW[1], the pulse of the third data write gate signal GW[3] can be positioned in the immediately next horizontal period of the pulse of the first data write gate signal GW[1].

[0150] As shown in FIG. 2, in the first duration of the alternate driving mode, the odd-numbered gate lines can be scanned by the odd-numbered data write gate signals GW[1], GW[3], …, GW[M-1]. In this exemplary embodiment, M can be an even number. In this exemplary embodiment, the pulse of the first data write gate signal GW[1] can be positioned in the first horizontal period of the frame. In this exemplary embodiment, the pulse of the third data write gate signal GW[3] can be positioned in the third horizontal period of the frame. Figure 19 Unlike the second data write gate signal GW[2], the pulse of the fourth data write gate signal GW[4] can be positioned in the immediately next horizontal period of the pulse of the second data write gate signal GW[2]. Figure 10

[0151] In this exemplary embodiment, the width of the gate pulse in the first duration of the alternate driving mode can be substantially the same as the width of the gate pulse in the compensation frame. In the same manner, the width of the gate pulse in the second duration of the alternate driving mode can be substantially the same as the width of the gate pulse in the compensation frame.

[0152] According to this exemplary embodiment, the driving controller 200 drives the display panel 100 at a moving image driving frequency in the moving image mode, and the driving controller 200 drives the display panel 100 at a static image driving frequency in the static image mode. Thus, the power consumption of the display apparatus can be reduced.

[0153] In addition, in the static image mode, the driving controller 200 can operate the gate driver 300 in the alternate driving mode such that the gate driver 300 scans the first group of gate lines in the first duration and scans the second group of gate lines in the second duration. Thus, flicker due to current leakage of the pixels can be prevented. In addition, when an image transition occurs in the static image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines such that flicker due to a luminance difference between a first frame and a second frame after the image transition in the static image mode can be prevented. Thus, the display quality of the display panel 100 can be enhanced.

[0154] Figure 20 ​is a flowchart showing an operation of a driving controller of a display apparatus according to an exemplary embodiment of the present inventive concept.

[0155] In addition to the operation of the driving controller, the display apparatus and the method of driving the display apparatus according to the present exemplary embodiment are substantially the same as those described with reference to Figures 1 to 13 The display apparatus and the method of driving the display apparatus of the previous exemplary embodiment explained above are substantially the same. Therefore, the same reference numerals will be used to indicate the parts which are the same or similar to those described in the previous exemplary embodiment, and any repeated explanation regarding the above elements will be omitted. Figures 1 to 13

[0156] With reference to Figures 1 to 6 , Figures 8 to 13 and Figure 20 , the display apparatus includes a display panel 100 and a display panel driver. The display panel driver includes a driving controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power supply voltage generator 700.

[0157] The driving controller 200 can determine whether a display mode of the display panel 100 is a moving image mode or a still image mode according to input image data IMG. In the moving image mode, the driving controller 200 can drive the display panel 100 at a moving image driving frequency. In the still image mode, the driving controller 200 can drive the display panel 100 at a still image driving frequency.

[0158] For example, in the still image mode, the driving controller 200 can operate the gate driver 300 in an alternate driving mode such that the gate driver 300 scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration. In addition, when an image transition occurs in the still image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines.

[0159] On the contrary, in the moving image mode, the driving controller 200 can operate the gate driver 300 in a normal driving mode such that the gate driver 300 scans all of the gate lines.

[0160] For example, the driving controller 200 can include a still image determiner 220 that determines whether the input image data IMG is a moving image or a still image, a driving frequency determiner 240 that determines a moving image driving frequency and a still image driving frequency, a driving mode determiner 260 that determines whether a driving mode of the display panel 100 is an alternate driving mode or a normal driving mode, and a compensation frame inserter 280 that inserts a compensation frame.

[0161] ​In the present exemplary embodiment, when an image transition occurs in the static image mode, the compensation frame inserter 280 can compare a difference between the gray value of the previous image and the gray value of the current image with the gray threshold value GTH (operation S250). When the difference between the gray value of the previous image and the gray value of the current image is greater than the gray threshold value GTH, the compensation frame inserter 280 can insert a compensation frame (operation S300).

[0162] When the difference between the gray value of the previous image and the gray value of the current image is equal to or less than the gray threshold value GTH, a compensation frame can not be inserted and the display panel 100 can operate in the alternate driving mode (operation S400). When the difference between the gray value of the previous image and the gray value of the current image is small, a problem of not displaying a desired brightness in the first frame after an image transition is not serious, so that flicker due to a difference between the brightness of the first frame and the brightness of the second frame after an image transition can not be generated.

[0163] Therefore, when the difference between the gray value of the previous image and the gray value of the current image is small, a compensation frame is not inserted, but operates in the alternate driving mode immediately after an image transition, so that power consumption can be further reduced.

[0164] According to the present exemplary embodiment, the driving controller 200 drives the display panel 100 at a moving image driving frequency in the moving image mode, and the driving controller 200 drives the display panel 100 at a static image driving frequency in the static image mode. Therefore, power consumption of the display apparatus can be reduced.

[0165] In addition, in the static image mode, the driving controller 200 can operate the gate driver 300 in the alternate driving mode, so that the gate driver 300 scans the first group of gate lines in the first duration and scans the second group of gate lines in the second duration. Therefore, flicker due to current leakage of a pixel can be prevented. In addition, when an image transition occurs in the static image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines, so that flicker due to a difference in brightness between the first frame and the second frame after an image transition in the static image mode can be prevented. Therefore, display quality of the display panel 100 can be enhanced.

[0166] Figure 21 FIG. 4 is a flowchart illustrating an operation of the driving controller 200 of the display apparatus according to an exemplary embodiment of the present inventive concept. Figure 22 FIG. 5 is a graph illustrating brightness of the display panel 100 of the display apparatus in a first alternate driving mode. Figure 23 FIG. 6 is a graph illustrating brightness of the display panel 100 of the display apparatus in a second alternate driving mode.

[0167] The display apparatus and the method of driving the display apparatus according to the present exemplary embodiment are substantially the same as those of the previously explained exemplary embodiment except for the operation of the driving controller. Thus, the same reference numerals will be used to indicate the portions which are the same or similar to those described in the previously explained exemplary embodiment, and any repeated explanation regarding the above elements will be omitted. Figures 1 to 13 The display apparatus and the method of driving the display apparatus of the previously explained exemplary embodiment are substantially the same. Thus, the same reference numerals will be used to indicate the portions which are the same or similar to those described in the previously explained exemplary embodiment, and any repeated explanation regarding the above elements will be omitted. Figures 1 to 13 The display apparatus according to the present exemplary embodiment includes a display panel 100 and a display panel driver. The display panel driver includes a driving controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power voltage generator 700.

[0168] Referring to Figures 1 to 6 , Figures 8 to 13 and Figures 21 to 23 , the display apparatus includes a display panel 100 and a display panel driver. The display panel driver includes a driving controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, and an emission driver 600. The display panel driver can further include a power voltage generator 700.

[0169] The driving controller 200 can determine whether a display mode of the display panel 100 is a moving image mode or a still image mode according to input image data IMG. In the moving image mode, the driving controller 200 can drive the display panel 100 at a moving image driving frequency. In the still image mode, the driving controller 200 can drive the display panel 100 at a still image driving frequency.

[0170] For example, in the still image mode, the driving controller 200 can operate the gate driver 300 in an alternate driving mode such that the gate driver 300 scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration. In addition, when an image transition occurs in the still image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines.

[0171] On the contrary, in the moving image mode, the driving controller 200 can operate the gate driver 300 in a normal driving mode such that the gate driver 300 scans all of the gate lines.

[0172] For example, the driving controller 200 can include a still image determiner 220 which determines whether the input image data IMG is a moving image or a still image, a driving frequency determiner 240 which determines a moving image driving frequency and a still image driving frequency, a driving mode determiner 260 which determines whether a driving mode of the display panel 100 is an alternate driving mode or a normal driving mode, and a compensation frame inserter 280 which inserts a compensation frame.

[0173] In this exemplary embodiment, the drive mode determiner 260 may determine the alternating drive mode as one of a first alternating drive mode and a second alternating drive mode based on the still image drive frequency. Although not shown in the figure, the drive mode determiner 260 may determine the alternating drive mode as one of three or more different alternating drive modes.

[0174] When the still image driving frequency is equal to or greater than the frequency threshold FTH (operation S270), the gate driver 300 can operate in the first alternating driving mode (operation S400). When the still image driving frequency is less than the frequency threshold FTH (operation S270), the gate driver 300 can operate in the second alternating driving mode (operation S450). The frequency threshold FTH can be determined as half of the input frequency of the input image data IMG. For example, when the input frequency of the input image data IMG is 60Hz, the frequency threshold FTH can be 30Hz. For example, when the input frequency of the input image data IMG is 120Hz, the frequency threshold FTH can be 60Hz.

[0175] When the alternating drive mode is determined to be the first alternating drive mode and an image transition occurs in the static image mode, the compensation frame inserter 280 may insert a compensation frame to scan all gate lines (operation S300). Similarly, when the alternating drive mode is determined to be the second alternating drive mode and an image transition occurs in the static image mode, the compensation frame inserter 280 may also insert a compensation frame to scan all gate lines (operation S350).

[0176] In the first alternating drive mode, the first group of gate lines can be odd-numbered gate lines, and the second group of gate lines can be even-numbered gate lines.

[0177] like Figure 22 As shown, in the first alternating drive mode, odd-numbered gate lines are scanned during a first duration (e.g., F1 and F3), such that a threshold voltage-compensated data voltage is written to the pixels connected to the odd-numbered (ODD) gate lines. Additionally, in the first alternating drive mode, even-numbered (EVEN) gate lines are scanned during a second duration (e.g., F2 and F4), such that a threshold voltage-compensated data voltage is written to the pixels connected to the even-numbered gate lines.

[0178] The user can distinguish the brightness L(ODD) of pixels connected to odd-numbered gate lines and the average brightness L(AVG) of pixels connected to even-numbered gate lines, such that the brightness L(AVG) displayed to the user in the first alternating drive mode can be increased compared to the normal drive mode. Therefore, flicker can be prevented in the static image mode (low-frequency drive mode) by means of the first alternating drive mode method.

[0179] In the second alternate driving mode, the display panel 100 can include a first group of gate lines, a second group of gate lines, a third group of gate lines, and a fourth group of gate lines. In the second alternate driving mode, the first group of gate lines can be the (4P+1)th gate line, the second group of gate lines can be the (4P+2)th gate line, the third group of gate lines can be the (4P+3)th gate line, and the fourth group of gate lines can be the (4P+4)th gate line. Herein, P can be an integer equal to or greater than zero.

[0180] As shown in FIG. 4B, in the second alternate driving mode, the (4P+1)th gate line is scanned during a first duration (e.g., F1 and F5) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+1)th gate line. Also, in the second alternate driving mode, the (4P+2)th gate line is scanned during a second duration (e.g., F2 and F6) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+2)th gate line. Also, in the second alternate driving mode, the (4P+3)th gate line is scanned during a third duration (e.g., F3 and F7) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+3)th gate line. Also, in the second alternate driving mode, the (4P+4)th gate line is scanned during a fourth duration (e.g., F4 and F8) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+4)th gate line. Figure 23 As shown in FIG. 4B, in the second alternate driving mode, the (4P+1)th gate line is scanned during a first duration (e.g., F1 and F5) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+1)th gate line. Also, in the second alternate driving mode, the (4P+2)th gate line is scanned during a second duration (e.g., F2 and F6) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+2)th gate line. Also, in the second alternate driving mode, the (4P+3)th gate line is scanned during a third duration (e.g., F3 and F7) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+3)th gate line. Also, in the second alternate driving mode, the (4P+4)th gate line is scanned during a fourth duration (e.g., F4 and F8) such that the threshold voltage-compensated data voltage is written into the pixels connected to the (4P+4)th gate line.

[0181] According to the present exemplary embodiment, the driving controller 200 drives the display panel 100 at a motion image driving frequency in the motion image mode, and the driving controller 200 drives the display panel 100 at a static image driving frequency in the static image mode. Accordingly, the power consumption of the display apparatus can be reduced.

[0182]

[0183] ​Also, in the static image mode, the driving controller 200 can operate the gate driver 300 in the first alternate driving mode such that the gate driver 300 scans the first set of gate lines in the first time duration and scans the second set of gate lines in the second time duration, and can operate the gate driver 300 in the second alternate driving mode such that the gate driver 300 scans the first set of gate lines in the first time duration, scans the second set of gate lines in the second time duration, scans the third set of gate lines in the third time duration, and scans the fourth set of gate lines in the fourth time duration. Accordingly, flicker due to current leakage of the pixels can be prevented. Also, when an image transition occurs in the static image mode, the driving controller 200 can insert a compensation frame to scan all of the gate lines such that flicker due to a difference in brightness between the first frame and the second frame after the image transition in the static image mode can be prevented. Accordingly, the display quality of the display panel 100 can be enhanced.

[0184] According to the inventive concept as explained above, power consumption can be reduced by a low frequency driving method, and the display quality of a display panel can be enhanced by preventing flicker.

[0185] The foregoing is a summary of the inventive concept and should not be construed as limiting. While some example embodiments of the inventive concept have been described, those skilled in the art will readily understand that there are many modification of the example embodiments that can be made without substantially departing from the novel teachings and advantages of the inventive concept. Accordingly, all such modifications are intended to be included within the scope of the inventive concept as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited functions and not only structural equivalents, but also equivalent structures. Accordingly, although the inventive concept has been described in detail with reference to particular embodiments, it will be apparent to those skilled in the art that a variety of modifications can be made without departing from the inventive concept. Accordingly, the inventive concept is not limited to the disclosed embodiments, but is intended to include all modifications and equivalents within the scope of the following claims. The inventive concept is defined by the claims appended hereto, with equivalents of the claims to be included within the scope of the claims.

Claims

1. A display apparatus comprising: a display panel including a plurality of pixels and configured to display an image based on input image data; a gate driver configured to apply a gate signal to gate lines of the display panel; a data driver configured to apply a data voltage to data lines of the display panel; and a drive controller configured to determine a mode of the display panel as a moving image mode or a still image mode according to whether the input image data is a moving image or a still image, wherein the drive controller is configured to drive the display panel at a moving image drive frequency in the moving image mode, and configured to drive the display panel at a still image drive frequency in the still image mode, wherein in the still image mode, the drive controller is configured to operate the gate driver in an alternate driving mode such that the gate driver scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration, and wherein when an image transition occurs in the still image mode, the drive controller is configured to insert a compensation frame to scan all of the gate lines, wherein when the image transition occurs in the still image mode, the drive controller is configured to compare a difference in a gray value of a previous image and a gray value of a current image with a gray threshold, and wherein when the difference in the gray value of the previous image and the gray value of the current image is greater than the gray threshold, the drive controller is configured to insert the compensation frame. a length of the first duration of the alternate driving mode is the same as a length of the second duration of the alternate driving mode.

2. The display device according to claim 1, wherein a length of the compensation frame is the same as the length of the first duration of the alternate driving mode and the length of the second duration of the alternate driving mode.

3. The display device of claim 2, wherein, the first set of gate lines are odd-numbered gate lines, and 4. The display device according to claim 1, wherein wherein the second set of gate lines are even-numbered gate lines. a width of a gate pulse in the first duration of the alternate driving mode is the same as a width of a gate pulse in the compensation frame.

5. The display device of claim 4, wherein, the width of the gate pulse in the first duration of the alternate driving mode is equal to or greater than twice the width of the gate pulse in the compensation frame.

6. The display device according to claim 4, wherein in the moving image mode, the drive controller is configured to operate the gate driver in a normal driving mode such that the gate driver scans all of the gate lines.

7. The display device according to claim 1, wherein the drive controller comprises:

8. The display device of claim 7, wherein, a still image determiner configured to determine whether the input image data is the moving image or the still image; a drive frequency determiner configured to determine the moving image drive frequency and the still image drive frequency; a drive mode determiner configured to determine whether a drive mode of the display panel is the alternate driving mode or the normal driving mode; and a compensation frame inserter configured to insert the compensation frame. 2.A display apparatus comprising: a display panel including a plurality of pixels and configured to display an image based on input image data; a gate driver configured to apply a gate signal to gate lines of the display panel; a data driver configured to apply a data voltage to data lines of the display panel; and a drive controller configured to determine a mode of the display panel as a moving image mode or a still image mode according to whether the input image data is a moving image or a still image, wherein the drive controller is configured to drive the display panel at a moving image drive frequency in the moving image mode, and configured to drive the display panel at a still image drive frequency in the still image mode, wherein in the still image mode, the drive controller is configured to operate the gate driver in an alternate driving mode such that the gate driver scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration, and wherein when an image transition occurs in the still image mode, the drive controller is configured to insert a compensation frame to scan all of the gate lines, wherein when the image transition occurs in the still image mode, the drive controller is configured to compare a difference in a gray value of a previous image and a gray value of a current image with a gray threshold, and wherein when the difference in the gray value of the previous image and the gray value of the current image is greater than the gray threshold, the drive controller is configured to insert the compensation frame. a length of the first duration of the alternate driving mode is the same as a length of the second duration of the alternate driving mode. a length of the compensation frame is the same as the length of the first duration of the alternate driving mode and the length of the second duration of the alternate driving mode. the first set of gate lines are odd-numbered gate lines, and wherein the second set of gate lines are even-numbered gate lines. a width of a gate pulse in the first duration of the alternate driving mode is the same as a width of a gate pulse in the compensation frame. the width of the gate pulse in the first duration of the alternate driving mode is equal to or greater than twice the width of the gate pulse in the compensation frame. in the moving image mode, the drive controller is configured to operate the gate driver in a normal driving mode such that the gate driver scans all of the gate lines. the drive controller comprises: a still image determiner configured to determine whether the input image data is the moving image or the still image; a drive frequency determiner configured to determine the moving image drive frequency and the still image drive frequency; a drive mode determiner configured to determine whether a drive mode of the display panel is the alternate driving mode or the normal driving mode; and a compensation frame inserter configured to insert the compensation frame. 9.A display apparatus comprising: a display panel including a plurality of pixels and configured to display an image based on input image data; a gate driver configured to apply a gate signal to gate lines of the display panel; a data driver configured to apply a data voltage to data lines of the display panel; and a drive controller configured to determine a mode of the display panel as a moving image mode or a still image mode according to whether the input image data is a moving image or a still image, wherein the drive controller is configured to drive the display panel at a moving image drive frequency in the moving image mode, and configured to drive the display panel at a still image drive frequency in the still image mode, wherein in the still image mode, the drive controller is configured to operate the gate driver in an alternate driving mode such that the gate driver scans a first set of gate lines in a first duration and scans a second set of gate lines in a second duration, and wherein when an image transition occurs in the still image mode, the drive controller is configured to insert a compensation frame to scan all of the gate lines, wherein when the still image drive frequency is equal to or greater than a frequency threshold, the drive controller is configured to operate the gate driver in a first alternate driving mode, and wherein when the still image drive frequency is less than the frequency threshold, the drive controller is configured to operate the gate driver in a second alternate driving mode. ​

Images