Display device and driving method of display device

Abstract

The invention discloses a display device and a driving method of the display device. The display device includes: a display module including a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; and a power supply configured to supply power for driving the display module. The display module operates in a sequence of driving preparation including a basic configuration required for operation of the operating device, driving waiting compensation including sensing at least one gate line for compensation of a driving waiting state of the display panel, and normal driving including displaying an image on the display panel.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10 - 2023 - 0197064, filed on December 29, 2023, which is hereby incorporated by reference in its entirety as if fully set forth herein. Technical field

[0003] The present disclosure relates to a display device and a method of driving the display device. Background art

[0004] With the advancement of information technology, the market for display devices as a connection medium between users and information is expanding. Accordingly, the use of display devices such as light - emitting display devices (LEDs), quantum dot display devices (QDDs), liquid crystal display devices (LCDs), etc. is increasing.

[0005] The above - mentioned display devices include a display panel having sub - pixels, a driver configured to output driving signals for driving the display panel, and a power supply configured to generate power to be supplied to the display panel, the driver, etc.

[0006] In such a display device, when driving signals such as scan signals and data signals are supplied to the sub - pixels formed in the display panel, the selected sub - pixels among the sub - pixels transmit light or directly emit light, and thus an image can be displayed. Summary of the invention

[0007] Accordingly, the present disclosure relates to a display device and a method of driving the display device that substantially eliminate one or more problems caused by limitations and disadvantages of the related art.

[0008] An object of the present disclosure is not only to eliminate problems of brightness variations (screen stains or line - shaped or block - shaped stains) caused by distortion of threshold voltage information that may occur when a display device is kept (or placed) without being driven for a long time, but also to appropriately compensate for brightness variations according to various environments and conditions, thereby improving compensation accuracy and compensation reliability.

[0009] The object of the present disclosure is not limited to the above - described object, and other objects not yet described of the present disclosure will be more clearly understood by those skilled in the art from the following detailed description.

[0010] To achieve these objects and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, a display device includes: a display module including a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; and a power supply configured to supply power for driving the display module, wherein the display module operates in the order of driving preparation, driving wait compensation, and normal driving, driving preparation includes basic configurations required for the operation of devices included in the display module, driving wait compensation includes sensing at least one gate line for compensation of a driving wait state of the display panel, and normal driving includes displaying an image on the display panel.

[0011] The display module may perform driving wait compensation when a sensing flag defined in the timing controller is active.

[0012] The display module may also perform driving preparation compensation between driving wait compensation and normal driving to sense all gate lines of the display panel.

[0013] The sensing flag may transition to an inactive state after the execution of driving wait compensation.

[0014] The sensing flag may remain inactive during the execution of normal driving.

[0015] The sensing flag may transition to an inactive state after the execution of driving wait compensation and driving preparation compensation.

[0016] The sensing flag may be regenerated to an active state when the display device deviates from the usage wait condition of the display panel.

[0017] The sensing flag may be regenerated to an active state when the display device deviates from the end compensation execution condition of the display panel.

[0018] In another aspect of the present disclosure, a driving method of a display device is disclosed, the display device including: a display module including a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; and a power supply configured to supply power for driving the display module, the driving method including driving preparation, driving wait compensation, and normal driving, driving preparation includes basic configurations required for the operation of devices included in the display module, driving wait compensation includes sensing at least one gate line for compensation of a driving wait state of the display panel, and normal driving includes displaying an image on the display panel.

[0019] The driving method may also perform driving preparation compensation between driving wait compensation and normal driving to sense all gate lines of the display panel.

[0020] The driving wait compensation may be performed when a sense flag defined in the timing controller is in an active state. The sense flag may be changed to an inactive state after the execution of the driving wait compensation.

[0021] The sensing flag may be generated again to have an active state when the display device deviates from the use waiting condition of the display panel or the end compensation execution condition of the display panel.

[0022] The present disclosure has the effect of being able to eliminate the problem of brightness variation (screen stains or linear or block stains) caused by distortion of threshold voltage information that may occur when the display device is held (or placed) for a long time without being driven. In addition, the present disclosure has the effect of being able to improve compensation accuracy by performing compensation per pixel based on a threshold voltage compensation value newly updated as the light-emitting display device is driven even when the light-emitting display device is held (or placed) for a long time without being driven. In addition, the present disclosure has the effect of being able to improve the compensation reliability of the light-emitting display device by forcibly performing end compensation when the light-emitting display device is repeatedly held (or placed) for a long time without being driven or when end compensation is not properly performed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this application. The accompanying drawings illustrate embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. In the drawings:

[0024] Figure 1 is a block diagram schematically illustrating a light emitting display device;

[0025] Figure 2 It is schematically shown Figure 1 The configuration diagram of the sub-pixels shown;

[0026] Figure 3 is a diagram showing a pixel composed of sub-pixels;

[0027] Figure 4 and Figure 5 is a diagram illustrating the configuration of a gate type scanning driver within a panel;

[0028] Figure 6 is a diagram showing an example of the arrangement of an in-panel gate type scanning driver;

[0029] Figure 7 is a diagram showing a sub-pixel, a data driver, and a timing controller according to an embodiment;

[0030] Figure 8It is a diagram for briefly explaining a method for the threshold voltage of a sensing driving transistor according to an embodiment;

[0031] Figure 9 It is a conceptual diagram for explaining a driving waiting compensation method according to a first embodiment;

[0032] Figure 10 It is a flowchart for explaining a driving waiting compensation method according to a first embodiment;

[0033] Figure 11 It is a block diagram for explaining the generation of a sensing flag for driving waiting compensation according to a first embodiment;

[0034] Figure 12 It is a schematic diagram of a sensing line for driving waiting compensation according to a first embodiment;

[0035] Figure 13 It is a conceptual diagram for explaining whether the driving waiting compensation according to a first embodiment has been executed and the change of the sensing flag;

[0036] Figure 14 It is a conceptual diagram for explaining a modification of a first embodiment;

[0037] Figure 15 It is a conceptual diagram for explaining a driving waiting compensation method according to a second embodiment;

[0038] Figure 16 It is a flowchart for explaining a driving waiting compensation method according to a second embodiment;

[0039] Figure 17 It is a conceptual diagram for explaining a driving waiting compensation method according to a third embodiment;

[0040] Figure 18 It is a conceptual diagram for explaining whether the driving waiting compensation according to a third embodiment has been executed and the change of the sensing flag;

[0041] Figure 19 It is a conceptual diagram for explaining whether the driving waiting compensation according to a third embodiment has been executed, the change of the sensing flag, and the state according to different driving modes;

[0042] Figure 20 It is a conceptual diagram for explaining the change of a sensing flag according to a fourth embodiment;

[0043] Figure 21 It is a conceptual diagram for explaining whether the driving waiting compensation according to a fourth embodiment has been executed, the change of the sensing flag, and the state according to different driving modes;

[0044] Figure 22 It is a conceptual diagram for explaining a modification of a fourth embodiment; and

[0045] Figures 23 to 26 This is a diagram for explaining reference matters in drive wait compensation according to the present disclosure. Detailed implementation manners

[0046] The display device according to the present disclosure can be implemented as a television, an image player, a personal computer (PC), a home theater, an automotive electronic device, a smart phone, etc., but is not limited thereto. The display device according to the present disclosure can be implemented as a light-emitting display device (LED), a quantum dot display device (QDD), a liquid crystal display device (LCD), etc. However, for ease of description, the following description will be given in conjunction with the following example: In this example, the display device according to the present disclosure is a light-emitting display device configured to directly emit light based on an inorganic light-emitting diode or an organic light-emitting diode.

[0047] Figure 1 This is a block diagram schematically showing a light-emitting display device. Figure 2 This is schematically showing Figure 1 a configuration diagram of the sub-pixels shown. Figure 3 This is a diagram showing a pixel composed of sub-pixels.

[0048] As Figures 1 to 3 shown, the light-emitting display device may include an image provider 110, a timing controller 120, a scan driver 130, a data driver 140, a display panel 150, a power supply 180, etc.

[0049] The image provider 110 (a kit or a host system) can output various driving signals and an image data signal supplied from the outside thereof or an image data signal stored in an internal memory. The image provider 110 can supply a data signal and various driving signals to the timing controller 120.

[0050] The timing controller 120 can output a gate timing control signal GDC for controlling the operation timing of the scan driver 130, a data timing control signal DDC for controlling the operation timing of the data driver 140, various synchronization signals, etc. The timing controller 120 can supply the data signal DATA supplied from the image provider 110 to the data driver 140 together with the data timing control signal DDC. The timing controller 120 can be in the form of an integrated circuit (IC) and can thus be mounted on a printed circuit board, but is not limited thereto.

[0051] The scan driver 130 may output a scan signal (or a scan voltage) in response to a gate timing control signal GDC or the like supplied from the timing controller 120. The scan driver 130 may supply the scan signal to sub-pixels included in the display panel 150 via gate lines GL1 to GLm. The scan driver 130 may be in the form of an IC, or may be directly formed on the display panel 150 in the form of an in-panel gate structure, but is not limited thereto.

[0052] The data driver 140 may sample and latch a data signal DATA in response to a data timing control signal DDC or the like supplied from the timing controller 120, may convert the data signal in digital form into a data voltage in analog form, and may then output the obtained data voltage. The data driver 140 may supply the data voltage to sub-pixels included in the display panel 150 via data lines DL1 to DLn. The data driver 140 may be in the form of an IC, and thus may be mounted on the display panel 150 or a printed circuit board, but is not limited thereto.

[0053] The power supply 180 may generate a first power at a high level and a second power at a low level based on an external input voltage supplied from the outside, may output the first power through a first power line EVDD, and may output the second power through a second power line EVSS. The power supply 180 may not only generate and output the first power and the second power, but may also generate and output a voltage required to drive the scan driver 130 (e.g., a scan high voltage and a scan low voltage) or a voltage required to drive the data driver 140 (a drain voltage and a semi-drain voltage).

[0054] The display panel 150 may display an image corresponding to a driving signal including a scan signal and a data voltage, a first power, a second power, etc. Sub-pixels of the display panel 150 may directly emit light. The display panel 150 may be manufactured based on a substrate having stiffness or ductility (such as glass, silicon, polyimide, etc.). For example, one sub-pixel SP may include a pixel circuit connected to a first data line DL1, a first gate line GL1, a first power line EVDD, and a second power line EVSS, and may be composed of a switching transistor, a driving transistor, a capacitor, an organic light emitting diode, etc.

[0055] In the sub-pixel SP used in the light-emitting display device, light is directly emitted, and thus its circuit configuration is complex. In addition, compensation circuits configured to compensate not only for the deterioration of the organic light emitting diode configured to emit light but also for the deterioration of driving transistors or the like configured to supply a driving current required to drive the organic light emitting diode are also diverse. Therefore, note that in Figure 2 the sub-pixel SP is simply shown in the form of a block.

[0056] The sub-pixels can emit red, green, or blue light, or can emit red, green, blue, or white light. Accordingly, one pixel P can include red, green, and blue sub-pixels, or can include red, green, blue, and white sub-pixels. For example, one pixel P can include a red sub-pixel SPR connected to a first data line DL1, a white sub-pixel SPW connected to a second data line DL2, a green sub-pixel SPG connected to a third data line DL3, and a blue sub-pixel SPB connected to a fourth data line DL4. Additionally, the red sub-pixel SPR, the white sub-pixel SPW, the green sub-pixel SPG, and the blue sub-pixel SPB can be commonly connected to a first reference line VREF1. The first reference line VREF1 can be used to sense the degradation, etc., of the element(s) included in one of the red sub-pixel SPR, the white sub-pixel SPW, the green sub-pixel SPG, and the blue sub-pixel SPB. This will be described later.

[0057] Meanwhile, heretofore, the timing controller 120, the scan driver 130, the data driver 140, etc. have been described as separate configurations. However, depending on the implementation method of the light-emitting display device, one or more of the timing controller 120, the scan driver 130, and the data driver 140 can be integrated in one IC. The timing controller 120, the scan driver 130, the data driver 140, and the display panel 150 can be defined as a display module.

[0058] In addition, an example of the pixel P in which the red sub-pixel SPR, the white sub-pixel SPW, the green sub-pixel SPG, and the blue sub-pixel SPB are arranged in this order has been shown. However, the setting order and direction of the sub-pixels can be changed according to the implementation method of the light-emitting display device.

[0059] Figure 4 and Figure 5 is a diagram illustrating the configuration of the in-panel gate-type scan driver. Figure 6 is a diagram showing an example of the setting of the in-panel gate-type scan driver.

[0060] As Figure 4 shown, the in-panel gate-type scan driver can include a shift register 131 and a level shifter 135. The level shifter 135 can generate driving clock signals Clks and a start signal Vst based on signals and voltages output from the timing controller 120 and the power supply 180.

[0061] The shift register 131 can operate based on signals Clks and Vst, etc., output from the level shifter 135, and can output scan signals Scan[1] to Scan[m] for turning on or off the transistors formed at the display panel. The shift register 131 can be formed in the form of a thin film on the display panel according to the in-panel gate method.

[0062] As Figure 4 and Figure 5 shown, the level shifter 135 may be independently formed in the form of an IC differently from the shift register 131, or may be included in the power supply 180. Of course, these configurations are merely illustrative, and the present disclosure is not limited thereto.

[0063] As Figure 6 shown, in an in-panel gate type scan driver, the shift registers 131a and 131b that output scan signals may be disposed in the non-active area NA of the display panel 150. Although Figure 6 an example in which the shift registers 131a and 131b are respectively disposed in the left and right non-active areas NA of the display panel 150 is shown, the shift registers 131a and 131b may also be respectively disposed in the upper and lower non-active areas NA of the display panel 150, or may be disposed in the active area AA of the display panel 150.

[0064] Figure 7 is a diagram showing a sub-pixel, a data driver, and a timing controller according to an embodiment. Figure 8 is a diagram briefly illustrating a method for the threshold voltage of a sensing driving transistor according to an embodiment.

[0065] As Figure 7 shown, one sub-pixel SP may include a switching transistor SW, a driving transistor DT, a sensing transistor ST, a capacitor CST, and an organic light emitting diode OLED.

[0066] The driving transistor DT may be connected to the first electrode of the capacitor CST at its gate electrode, while being connected to the first power line EVDD at its first electrode and to the anode of the organic light emitting diode OLED at its second electrode. The capacitor CST may be connected to the gate electrode of the driving transistor DT at its first electrode, while being connected to the anode of the organic light emitting diode OLED at its second electrode. The organic light emitting diode OLED may be connected to the second electrode of the driving transistor DT at its anode, while being connected to the second power line EVSS at its cathode.

[0067] The switching transistor SW may be connected to the first scan line Gate1 included in the first gate line GL1 at its gate electrode, while being connected to the first data line DL1 at its first electrode and to the gate electrode of the driving transistor DT at its second electrode. The sensing transistor ST may be connected to the second scan line Gate2 included in the first gate line GL1 at its gate electrode, while being connected to the first reference line VREF1 at its first electrode and to the anode of the organic light emitting diode OLED at its second electrode.

[0068] The switching transistor SW can be used to transfer the data voltage Vdata transmitted through the first data line DL1 to the capacitor CST. The sensing transistor ST can be used to sense a sensing node defined between the driving transistor DT and the organic light emitting diode OLED. The sensing transistor ST is a compensation circuit added to compensate for the deterioration (threshold voltage, mobility, etc.) of the driving transistor DT or the organic light emitting diode OLED. At the same time, the first gate line GL1 can have an integrated structure without being divided into a first scan line Gate1 and a second scan line Gate2. That is, the switching transistor SW and the sensing transistor ST can be commonly connected to the first gate line GL1, and thus can be turned on or off simultaneously.

[0069] The data driver denoted by the reference numeral "140" may include a driving circuit unit 141 configured to drive the sub-pixel SP and a sensing circuit unit 145 configured to sense elements included in the sub-pixel SP. The driving circuit unit 141 can output a data voltage Vdata for driving the sub-pixel SP through the first data line DL1 and the like. The sensing circuit unit 145 can obtain a sensed voltage Vsen sensed from the sub-pixel SP through the first reference line VREF1.

[0070] The timing controller denoted by the reference numeral "120" may include a compensator 123 and the like, which are configured to compensate the data signal DATA to be supplied to the sub-pixel SP based on the sensed voltage Vsen transmitted from the sensing circuit unit 145, so as to supply a compensated data signal CDATA. For example, the compensator 123 can obtain threshold voltage information (change value) of the driving transistor DT included in the sub-pixel SP (in the entire display panel) respectively, and can compensate the data signal DATA to eliminate problems caused by threshold voltage change (shift). The compensator 123 can update the threshold voltage information stored in the memory 125 of the driving transistor DT on a sub-pixel basis based on the sensed voltage Vsen respectively, and can provide a compensation value COMP for compensating the corresponding data signal DATA based on the updated threshold voltage information.

[0071] As Figure 7 and Figure 8 shown, when the scan signals applied to the first scan line Gate1 and the second scan line Gate2 respectively transition from a low voltage (L) to a high voltage (H), basic operating conditions required for sensing can be established.

[0072] The sensing transistor ST can physically sense the threshold voltage Vth based on the source follower operation of the driving transistor DT. The source node voltage (source node [V]) of the driving transistor DT can rise along a predetermined curve over time.

[0073] However, the source node voltage (source node [V]) of the driving transistor DT may rise to the threshold voltage Vth of the driving transistor DT before reaching the target voltage. The sensing transistor ST can sense the time when the source node voltage (source node [V]) of the driving transistor DT rises to the threshold voltage Vth of the driving transistor DT. Therefore, the sensing transistor ST senses the threshold voltage Vth of the driving transistor DT by sensing the voltage Vsen.

[0074] Figure 8 is a schematic diagram to support the understanding of a voltage sensing method configured to obtain a voltage in a method of sensing the threshold voltage Vth of the driving transistor DT using the sensing transistor ST. A method of sensing elements included in the sub-pixel SP using the sensing transistor ST and the like can be performed based on various methods such as a current sensing method configured to obtain a current and various circuits. Therefore, the sensing methods applicable to the present disclosure are not limited to Figure 7 the circuits of Figure 8 and

[0075] Meanwhile, according to the experimental results, it can be seen that the display panel included in the light-emitting display device may exhibit characteristic changes caused by deterioration not only when the light-emitting display device is driven for a long time, but also when the light-emitting display device is held (or placed) for a long time without being driven. Here, the conditions under which the display panel is held for a long time without being driven may vary depending on the storage period (or transportation period) or storage environment (temperature, humidity, etc.).

[0076] To this end, the present disclosure proposes a solution for eliminating / reducing problems that may occur for various reasons when the light-emitting display device is held (or placed) for a long time without being driven.

[0077] Figure 9 is a conceptual diagram illustrating a driving wait compensation method according to a first embodiment. Figure 10 is a flowchart illustrating a driving wait compensation method according to a first embodiment. Figure 11 is a block diagram illustrating the generation of a sensing flag for driving wait compensation according to a first embodiment. Figure 12 is a schematic diagram illustrating a sensing line for driving wait compensation according to a first embodiment.

[0078] As Figure 9 shown, the light-emitting display device according to the first embodiment may operate in the order of driving preparation CONFIG, driving wait compensation LT-VSC, and normal driving NOR-DRV.

[0079] The driving preparation CONFIG is the following steps: the basic configuration required for operating the light-emitting display device after applying power (AC power and DC power) ( Figure 1 such as the timing controller, etc.). The driving wait compensation LT-VSC is the following steps: sensing the sub-pixels set at the display panel, so as to compensate for the driving wait state according to the conditions internally set in the light-emitting display device, such as whether the light-emitting display device has been kept (or placed) without being driven for a long time. The normal driving NOR-DRV is the following steps: displaying an image on the display panel while driving the light-emitting display device under normal conditions (or general conditions).

[0080] Meanwhile, the driving wait compensation LT-VSC can be executed when the display panel is in a state where it displays black on its screen, but is not limited thereto. For example, the driving wait compensation LT-VSC can be executed while the display panel displays text such as "Driving wait compensation in progress" or "Driving preparation in progress" on its screen. Of course, the area where the text is displayed can be excluded from the rows of the display panel to be sensed.

[0081] As Figures 9 to 12 shown, the light-emitting display device can determine whether the state of the sensing flag SFLAG is high (1) (active state) (SFLAG == 1) (S10). For example, the sensing flag SFLAG can be generated in the image supplier (kit or host system) 110, or can be generated in the timing controller 120. The image supplier 110 and the timing controller 120 can share the state of the sensing flag SFLAG for efficient device control and compensation. Additionally, if necessary, the sensing flag SFLAG can be generated in the image supplier 110 according to the request of the timing controller 120, or can be generated in the timing controller 120 according to the request of the image supplier 110.

[0082] When the state of the sensing flag SFLAG is not high (1) (low (0) state or inactive state) (N), the normal driving NOR-DRV can be executed without performing the driving wait compensation LT-VSC (S60). On the other hand, when the state of the sensing flag SFLAG is high (1) (Y), the driving wait compensation LT-VSC can be executed. This will be described below.

[0083] When the driving wait compensation LT-VSC starts, the light-emitting display device can sense N gate lines (N is an integer greater than or equal to 1) from the display panel (S20). In the first example, the light-emitting display device can define one gate line set at a specific position of the display panel 150 as the sensing line, as Figure 12as shown in the upper part of, and then the gate lines can be sensed. In the second example, the light-emitting display device may define three gate lines provided at specific positions of the display panel 150 as sensing lines (a first sensing line, a second sensing line, and a third sensing line), as Figure 12 shown in the lower part of, and then these gate lines can be sequentially sensed.

[0084] Sensing one gate line may mean sensing sub-pixels included in the display panel 150 according to different colors. For example, as Figure 3 shown, when the display panel 150 is implemented based on pixels P each including a red sub-pixel SPR, a white sub-pixel SPW, a green sub-pixel SPG, and a blue sub-pixel SPB, color-based sensing voltages can be obtained from the sub-pixels, respectively.

[0085] The number of sensing lines that can be set in the driving wait compensation LT-VSC can be defined as a minimum of 1 to a maximum of 8 (that is, N = 1 to 8). This is because, when the number of sensing lines increases, although there are advantages in terms of improved accuracy, the time consumption in this case should be considered. Of course, this is only illustrative, and the present disclosure is not limited to the conditions described above.

[0086] Thereafter, a threshold voltage change value ΔVth can be calculated based on the sensing voltages obtained by sensing the sub-pixels connected to the N gate lines, and a relationship f(Vth) between the threshold voltage change value ΔVth and the initial threshold voltage can be obtained (ΔVth = f(Vth)) (S30). Here, the relationship f(Vth) between the threshold voltage change value ΔVth and the initial threshold voltage can be obtained based on a linear function including a slope and an intercept. This will be described later.

[0087] Next, it can be determined whether an average threshold voltage change value ΔVth_avg deviates from an internally set reference threshold voltage value Threshold (ΔVth_avg > Threshold) (S40). At the same time, when using the average threshold voltage change value ΔVth_avg instead of the threshold voltage change value ΔVth, sensing noise that may be generated during sensing can be minimized or removed. However, this is only an illustrative method for minimizing or removing sensing noise, and it can be determined whether the threshold voltage change value ΔVth deviates from the internally set reference threshold voltage value Threshold.

[0088] Thereafter, when the average threshold voltage change value ΔVth_avg does not deviate from the reference threshold voltage value Threshold (N), normal driving NOR-DRV (S60) can be performed without performing the subsequent step S50. On the other hand, when the average threshold voltage change value ΔVth_avg deviates from the reference threshold voltage value Threshold (Y), the step of applying the threshold voltage change value ΔVth to the threshold voltage compensation value for each pixel can be performed (S50).

[0089] Thereafter, normal driving NOR-DRV can be performed because driving wait compensation LT-VSC (S60) is completed by performing the step of applying the threshold voltage change value ΔVth to the threshold voltage compensation value for each pixel. Although the sense flag SFLAG can be maintained in the low state (state of 0 or inactive state) during normal driving NOR-DRV, the sense flag SFLAG can become active again when the sense flag SFLAG does not satisfy the internally set conditions. This will be described below.

[0090] Figure 13 It is a conceptual diagram illustrating whether the driving wait compensation according to the first embodiment has been performed and the change of the sense flag. Figure 14 It is a conceptual diagram illustrating a modification of the first embodiment.

[0091] As can be seen from Figure 13 the operation flow D-FLOW shown, when the manufacturer sets the basic state of the sense flag SFLAG to high (1) after performing the final inspection F-INSF on the light-emitting display device, the sense flag SFLAG can be maintained for the first period TP1 and the second period TP2.

[0092] The first period TP1 can be defined as the delivery waiting period or transportation period of the light-emitting display device for which the final inspection F-INSF has been completed. Typically, the first period TP1 can be a relatively long period that can be defined in days, for example, it can be about 10 days to 100 days.

[0093] The second period TP2 can be defined as the receiving inspection period taken by the company that receives the delivered light-emitting display device. The receiving inspection can vary depending on the different companies that receive the light-emitting display device, and thus its description will not be given.

[0094] Figure 13This is a schematic diagram showing the following: turning on / off a light-emitting display device at the first time 1T, the second time 2T, and the third time 3T in the second period TP2, and performing drive wait compensation LT-VSC at the third time 3T. Performing drive wait compensation LT-VSC at the third time 3T means that drive wait compensation LT-VSC is not normally performed at the first time 1T and the second time 2T because the light-emitting display device is forcibly turned off at the first time 1T and the second time 2T. Here, "forcibly turned off" may not correspond to the case of turning off the light-emitting display device using a remote control, but may correspond to the case of unplugging the power plug of the light-emitting display device from the power outlet.

[0095] Meanwhile, as described above, drive wait compensation LT-VSC may have a condition that enables it to be performed when the state of the sense flag SFLAG remains high (1). Therefore, even if the display panel is turned on / off multiple times in the second period TP2, the sense flag SFLAG may only change to low (0) when performing end compensation, which will be described later with reference to Figure 14 the description. The description related to end compensation may refer to the following description.

[0096] As Figure 14 shown, according to a modification of the first embodiment, the light-emitting display device may operate in the order of drive preparation CONFIG, drive wait compensation LT-VSC, normal drive NOR-DRV, and end compensation PE-CMP.

[0097] In the case where the execution time of normal drive NOR-DRV is long (that is, in the case of displaying an image for a long time), the sub-pixels included in the display panel may deteriorate over time. As described above, the display panel included in the light-emitting display device may not only exhibit changes in characteristics caused by deterioration when the light-emitting display device is driven for a long time, but may also exhibit changes in characteristics even when the light-emitting display device is kept (or placed) without being driven for a long time.

[0098] Although drive wait compensation LT-VSC has been performed in consideration of the above characteristics, the modification of the first embodiment may perform end compensation PE-CMP to compensate for changes in characteristics caused by deterioration during long-term execution of normal drive NOR-DRV.

[0099] End compensation PE-CMP may employ the same sensing method as drive-wait compensation LT-VSC. However, end compensation PE-CMP may differ from drive-wait compensation LT-VSC in that end compensation PE-CMP includes substantial degradation compensation. For example, a light-emitting display device may sense all gate lines of a display panel to obtain color-based sensed voltages, and may change and update corresponding pixel-based threshold voltage compensation values and the like according to the color-based sensed voltages.

[0100] When end compensation PE-CMP is performed after normal drive NOR-DRV is executed for a long time, as described above, the additional change value may be specifically reflected in the threshold change value ΔVth reflected in each pixel-based threshold voltage compensation value in drive-wait compensation LT-VST, and thus, each pixel-based threshold voltage compensation value may be updated again. That is, a threshold voltage compensation value (on which the degradation state up to the final degradation state before the end of driving of the display panel has been reflected) may be provided, and thus, the compensation accuracy when the display panel is driven again may be improved.

[0101] As is apparent from the above description, the first embodiment can eliminate the following problem: luminance variations (screen stains or line or block stains) caused by distortion of threshold voltage information that may occur when a light-emitting display device is held (or placed) for a long time without being driven.

[0102] Figure 15 is a conceptual diagram illustrating a drive-wait compensation method according to a second embodiment. Figure 16 is a flowchart illustrating a drive-wait compensation method according to a second embodiment.

[0103] As Figure 15 and Figure 16 shown, a light-emitting display device according to the second embodiment may operate in the order of drive preparation CONFIG, drive-wait compensation LT-VSC, start compensation PS-CMP, and normal drive NOR-DRV.

[0104] According to the second embodiment, when the state of the sensing flag SFLAG is not high (1) (low or 0) (N), the start compensation PS-CMP can be performed without performing the driving wait compensation LT-VSC, and then the normal driving NOR-DRV can be performed (S70). In addition, when the average threshold voltage change value ΔVth_avg does not deviate from the reference threshold voltage value Threshold (N), even if the driving wait compensation LT-VSC is being performed, the start compensation PS-CMP can be performed (S60), and then the normal driving NOR-DRV can be performed (S70). The remaining steps are similar to those of the first embodiment, and thus the description given in connection with the first embodiment can be referred to.

[0105] The start compensation PS-CMP can employ the same sensing method as the end compensation PE-CMP. When the start compensation PS-CMP is performed after the driving wait compensation LT-VSC is performed, even when the light-emitting display device is held (or placed) for a long time without being driven, the compensation for each pixel can be performed based on the threshold voltage compensation value newly updated as the display panel is driven.

[0106] The start compensation PS-CMP and the end compensation PE-CMP correspond to the following steps: sensing all the gate lines of the display panel before the display panel displays an image through its driving (immediately after the display panel is turned on) or after the display panel displays an image (immediately before the display panel is turned off), and performing pixel-based compensation based on the threshold voltage compensation value when the display module is turned on / off, and thus can be included in the driving preparation compensation.

[0107] As is apparent from the above description, the second embodiment can improve the compensation accuracy by performing pixel-based compensation based on the threshold voltage compensation value newly updated as the light-emitting display device is driven even when the light-emitting display device is held (or placed) for a long time without being driven.

[0108] Figure 17 is a conceptual diagram illustrating a driving wait compensation method according to the third embodiment. Figure 18 is a conceptual diagram illustrating whether the driving wait compensation according to the third embodiment has been performed and the change of the sensing flag. Figure 19 is a conceptual diagram illustrating whether the driving wait compensation according to the third embodiment has been performed, the change of the sensing flag, and the states according to different driving modes.

[0109] As Figure 17As shown, according to the third embodiment, the light-emitting display device can operate in the order of drive preparation CONFIG, drive wait compensation LT-VSC, start compensation PS-CMP, end compensation PE-CMP, and normal drive NOR-DRV. The third embodiment can be selected when reception inspection is performed during an extended period.

[0110] As can be seen from Figure 18 the operation flow D-FLOW shown, when the manufacturer sets the basic state of the sense flag SFLAG to high (1) after performing the final inspection F-INSF on the light-emitting display device, the sense flag SFLAG can be maintained for the first time period TP1 and the second time period TP2. The third time period TP3 corresponds to the normal drive NOR-DRV performed after the sense flag SFLAG transitions to low (0).

[0111] According to the third embodiment, even if the drive wait compensation LT-VSC is performed alone or together with the start compensation PS-CMP during the second time period TP2, the light-emitting display device can be set such that the state of the sense flag SFLAG transitions to low (0) only when the end compensation PE-CMP is finally executed. In other words, Figure 17 the start compensation PS-CMP in can be omitted, that is, the light-emitting display device can operate in the order of drive preparation CONFIG, drive wait compensation LT-VSC, end compensation PE-CMP, and normal drive NOR-DRV.

[0112] Figure 18 is a schematic diagram showing the following: The light-emitting display device is turned on / off at the first time 1T, the second time 2T, and the third time 3T during the second time period TP2, the drive wait compensation LT-VSC is performed at the first time 1T, and the end compensation PE-CMP is performed at the third time 3T. Performing the end compensation PE-CMP at the third time 3T can mean that the end compensation PE-CMP is not normally executed at the first time 1T and the second time 2T because the light-emitting display device is forcibly turned off at the first time 1T and the second time 2T.

[0113] As Figure 19 shown, the light-emitting display device can perform the drive wait compensation LT-VSC multiple times during the second time period TP2. This is because the sense flag SFLAG remains high (1) unless the end compensation PE-CMP is executed.

[0114] Figure 19 Similar to Figure 18, but it is a schematic diagram showing the following: Unless the end compensation PE-CMP is normally executed, the sense flag SFLAG can remain high (1) continuously, and the sensing for performing the drive wait compensation LT-VSC (LT-VSC sensing) can also be executed each time the light-emitting display device is turned on / off.

[0115] Referring to Figure 19 the drive mode DRVM shown, the compensation method of the light-emitting display device can be classified into a drive wait compensation method LT-CMP and a normal drive compensation method NOR-CMP according to the state of the sense flag SFLAG. The compensation method executed during the period when the sense flag SFLAG remains high (1) can be included in the drive wait compensation method LT-CMP.

[0116] Therefore, Figure 17 the start compensation PS-CMP of Figure 18 and Figure 19 the end compensation PE-CMP of

[0117] As is obvious from the above description, the third embodiment can eliminate the problem of brightness change (screen stain or linear or block stain) caused by the distortion of the threshold voltage information in a relatively short time by: Even when the light-emitting display device is kept (or placed) for a long time without being driven, pixel-based compensation is necessarily performed based on the threshold voltage compensation value newly updated as the light-emitting display device is driven.

[0118] Figure 20 is a conceptual diagram illustrating the change of the sense flag according to the fourth embodiment. Figure 21 is a conceptual diagram illustrating whether the drive wait compensation according to the fourth embodiment has been executed, the change of the sense flag, and the state according to different drive modes. Figure 22 is a conceptual diagram illustrating the modification of the fourth embodiment.

[0119] As Figure 20 shown, according to the fourth embodiment, when the sense flag SFLAG deviates from the internally set condition after changing from the high (1) state to the low (0) state (I > I_th), the sense flag SFLAG can change back to the high (1) state again. In this case, the sense flag SFLAG can change to the low (0) state after at least the execution of the drive wait compensation. This will be described below in combination with examples.

[0120] As can be seen from the operation flow D-FLOW shown in Figure 21 , except for the delivery waiting period, the transportation period, and the receiving inspection period, the light-emitting display device may have a period during which the light-emitting display device is basically not used, such as a use waiting period. The light-emitting display device may regenerate the sensing flag SFLAG according to whether the light-emitting display device deviates from the use waiting condition (in hours, days, or a combination of days and hours). This will be described below.

[0121] When the light-emitting display device operates before deviating from the use waiting condition (e.g., in terms of time) (T < T_th), the light-emitting display device may not regenerate the sensing flag SFLAG again. In this case, as can be seen from the first time 1T and the second time 2T, the light-emitting display device may be in a state where the end compensation PE-CMP has been completed after the normal execution of the end compensation PE-CMP. For reference, the sensing flag SFLAG may be regenerated again by the image supplier 110 or the timing controller 120, as can be seen from Figure 11 can be seen.

[0122] On the other hand, when the light-emitting display device does not operate after deviating from the use waiting condition (e.g., in terms of time) (T > T_th), the light-emitting display device may regenerate the sensing flag SFLAG again. In this case, the light-emitting display device may change the sensing flag SFLAG to low (0) after performing at least one of the compensation methods included in the drive waiting compensation method LT-CMP, as can be seen from the third time 3T.

[0123] Figure 21 An example is shown in which the light-emitting display device changes the sensing flag SFLAG to low (0) after performing the drive waiting compensation LT-VSC and the end compensation PE-CMP included in the drive waiting compensation method LT-CMP. For reference, the condition for changing the sensing flag SFLAG to low (0) may be selected differently, as described in the previous embodiment.

[0124] As can be seen from Figure 22 , except for the delivery waiting period, the transportation period, the receiving inspection period, and the use waiting period, the light-emitting display device may have a period during which the end compensation PE-CMP is not continuously executed. The light-emitting display device may regenerate the sensing flag SFLAG according to whether the light-emitting display device deviates from the internally set end compensation execution condition. This will be described below.

[0125] When compensating for PE-CMP at the end of normal execution, for example, at the first time T1 and the second time 2T, the light-emitting display device may not generate the sense flag SFLAG again. In this case, the light-emitting display device may execute the normal drive compensation method NOR-CMP that does not include the drive wait compensation LT-VSC.

[0126] On the other hand, when the end compensation PE-CMP is not executed (Fail) at the internally set time (e.g., the third time 3T to the nth time nT (C > C_th)) ("Fail" means non-execution of the end compensation), the light-emitting display device may generate the sense flag SFLAG with a high level (1) again. In this case, the light-emitting display device may change the sense flag SFLAG to a low level (0) after executing at least one of the compensation methods included in the drive wait compensation method LT-CMP, as can be seen from the (n + 1)th time (n + 1)T.

[0127] Figure 22 An example is shown in which the light-emitting display device changes the sense flag SFLAG to a low level (0) after executing the drive wait compensation LT-VSC and the end compensation PE-CMP included in the drive wait compensation method LT-CMP at the (n + 1)th time (n + 1)T. As a reference, the condition for changing the sense flag SFLAG to a low level (0) may be selected differently, as described in the previous embodiment.

[0128] As is apparent from the above description, the fourth embodiment can improve the compensation reliability of the light-emitting display device by forcibly performing the drive wait compensation when the repeated light-emitting display device is kept (or placed) for a long time without being driven or when the end compensation is not properly executed.

[0129] Figures 23 to 26 It is a diagram for explaining matters of reference in the drive wait compensation according to the present disclosure. However, in the following description, only matters that may be considered in order to seek a solution for improving the compensation accuracy while minimizing or eliminating sense noise, errors, etc. in the compensation of the threshold voltage of the drive transistor will be described.

[0130] As Figure 23 shown, it is possible to consider threshold voltage (Vth) variation modeling S100, parameter modeling S110, compensation S120 based on the derived parameters, etc., in order to more easily perform the drive wait compensation according to the present disclosure.

[0131] Threshold voltage (Vth) variation modeling S100 is as follows: Model the threshold voltage variation of the color-based driving transistors of the sub-pixels in the non-driven state (such as storage / transportation, etc.) where the light-emitting display device is not driven. The threshold voltage (Vth) variation of each driving transistor can be modeled based on a linear function with the threshold voltage value of the driving transistor as a variable.

[0132] As Figure 24 and Figure 25 shown, the threshold voltage variation of the color-based driving transistors of the sub-pixels in the non-driven state where the light-emitting display device is not driven can change according to time conditions, environmental conditions, etc., such as an increase in the storage (transportation) period, a change in the storage (transportation) environment, etc. Therefore, when modeling the threshold voltage (Vth) variation, it is preferable to refer to the above characteristics. In addition, the threshold voltage (Vth) variation modeling S100 can also include a modeling check for determining the appropriateness, effectiveness, consistency, etc. of the modeled values.

[0133] Parameter modeling S110 is as follows: Model the relationship between the values of the threshold voltage compensation of the driving transistors before and after based on at least two parameters. The relationship between the pre-storage threshold voltage compensation value COMP and the post-storage threshold voltage compensation value ΔCOMP can be modeled for each of the color-based driving transistors of the sub-pixels R / W / G / B, as long as there are two parameters, namely the x-intercept COMP_max and the slope COMP_slope, in the graph modeled based on the linear function, as Figure 26 shown. The pre-storage threshold voltage compensation value COMP can be the threshold voltage compensation value of each driving transistor given in the final inspection (or delivery) of the light-emitting display device, and the post-storage threshold voltage compensation value ΔCOMP can be the threshold voltage compensation value that changes according to the driving wait of the light-emitting display device.

[0134] Since the threshold voltage variation of each of the color-based driving transistors of the sub-pixels in the non-driven state (such as storage / transportation, etc.) can be obtained based on a linear function, the above modeling can be achieved as long as there are two pieces of pixel data that can provide two parameters. Therefore, the relationship between the values of the threshold voltage of each driving transistor before and after can be modeled by sensing only one gate line and obtaining two pieces of pixel data.

[0135] In addition, on one gate line, there are not only sub-pixels configured to emit one color but also sub-pixels configured to emit multiple colors. Therefore, even when only one gate line is sensed, the relationship between the values of the threshold voltage compensation of the driving transistors before and after can be provided separately for the different colors of the sub-pixels R / W / G / B.

[0136] In addition,Figure 26 It is a modeling diagram depicted based on average vertical data (3840 pieces of data obtained by averaging 2160 pieces of data each for sub-pixels R / W / G / B). When only a part of the data is used to configure the modeling diagram for compensating the non-driven state (storage / transportation, etc.), its accuracy may be reduced due to sensing noise or errors, etc. Therefore, when the modeling diagram is configured based on the average data obtained by averaging multiple pieces of data obtained from different colors based on sub-pixels R / W / G / B, noise or errors can be minimized or eliminated.

[0137] The compensation S120 based on the obtained parameters is as follows: perform the above-described drive waiting compensation, and compensate the threshold voltage of the color-based drive transistors of the sub-pixels in the non-driven state (storage / transportation, etc.) based on the parameters obtained from the modeling diagram.

[0138] As is apparent from the above description, the present disclosure has the effect of being able to eliminate the problem of brightness variations (screen stains or linear or blocky stains) caused by distortion of threshold voltage information that may occur when the display device is held (or placed) for a long time without being driven. Additionally, the present disclosure has the effect of being able to improve the compensation accuracy by performing per-pixel compensation based on the threshold voltage compensation value newly updated as the light-emitting display device is driven even when the light-emitting display device is held (or placed) for a long time without being driven. Furthermore, the present disclosure has the effect of being able to improve the compensation reliability of the light-emitting display device by forcibly executing the end compensation when the situation where the light-emitting display device is held (or placed) for a long time without being driven is repeated or when the end compensation is not properly executed.

[0139] The effects of the exemplary embodiments according to the present disclosure are not limited to the above, and more different effects may be included in the description.

[0140] Although the preferred embodiments of the present disclosure have been disclosed for illustrative purposes, those skilled in the art will recognize that various modifications, additions, and substitutions are possible without departing from the scope and spirit of the present disclosure as disclosed in the appended claims.

Claims

1. A display device, comprising: A display module, the display module comprising a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; as well as a power supply configured to supply power for driving the display module, The display module operates in the order of drive preparation, drive wait compensation and normal drive, wherein the drive preparation includes the basic configuration required for the operation of the operating device, the drive wait compensation includes sensing at least one gate line for compensation of the drive wait state of the display panel, and the normal drive includes displaying an image on the display panel.

2. The display device according to claim 1, wherein: The display module performs the driving wait compensation when a sensing flag defined in the timing controller is in an active state.

3. The display device according to claim 2, wherein: The display module also performs driving preparation compensation between the driving standby compensation and the normal driving to sense all gate lines of the display panel.

4. The display device according to claim 2, wherein: The sensing flag is turned into an inactive state after the execution of the driving wait compensation.

5. The display device according to claim 4, wherein: The sensing flag maintains the inactive state during execution of the normal driving.

6. The display device according to claim 3, wherein: The sensing flag is turned into an inactive state after execution of the drive standby compensation and the drive preparation compensation.

7. The display device according to claim 2, wherein: When the display device deviates from the use waiting condition of the display panel, the sensing flag is generated again to have the active state.

8. The display device according to claim 2, wherein: When the display device deviates from the end compensation execution condition of the display panel, the sensing flag is generated again to have the active state.

9. The display device according to claim 1, wherein: The display module also performs end compensation after the normal driving to compensate for a change in characteristics caused by degradation when the normal driving is performed.

10. The display device according to claim 3, wherein: The driving preparation compensation includes at least one of start compensation and end compensation.

11. A method for driving a display device, the display device comprising: A display module, the display module comprising a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; and a power supply configured to supply power for driving the display module, the driving method comprising: driving preparation, the driving preparation including basic configuration required for operating the devices included in the display module; driving standby compensation, the driving standby compensation comprising sensing at least one gate line for compensation of a driving standby state of the display panel; and Normal driving, the normal driving includes displaying an image on the display panel.

12. The driving method according to claim 11, further comprising: A driving preparation compensation between the driving standby compensation and the normal driving is performed to sense all gate lines of the display panel.

13. The driving method according to claim 11, wherein: When a sensing flag defined in the timing controller is in an active state, performing the driving wait compensation; and The sensing flag is turned into an inactive state after the execution of the driving wait compensation.

14. The driving method according to claim 13, wherein: When the display device deviates from the use waiting condition of the display panel or the end compensation execution condition of the display panel, the sensing flag is generated again to have the active state. 15 . The driving method according to claim 11 , further comprising an end compensation after the normal driving, the end compensation being performed to compensate for a change in characteristics caused by degradation when the normal driving is performed.

16. The driving method according to claim 12, wherein: The driving preparation compensation includes at least one of start compensation and end compensation.

17. A display device comprising: A display module, the display module comprising a display panel configured to display an image, a driver configured to drive the display panel, and a timing controller configured to control the driver; as well as a power supply configured to supply power for driving the display module, wherein the display module is configured to operate in one of a drive waiting compensation method and a normal driving compensation method according to a state of a sensing flag to compensate for a change in characteristics of the display panel, Wherein, when the sensing flag is in an active state, the display module is configured to operate with the drive waiting compensation method, and Among them, in the driving waiting compensation method, at least one of driving waiting compensation, start compensation and end compensation is performed; in the normal driving compensation method, the display module is operated in a normal driving manner, and the normal driving includes displaying an image on the display panel.

18. The display device according to claim 17, wherein: The sensing flag is generated to have the active state when the display device deviates from a use waiting condition of the display panel or an end compensation execution condition of the display panel.

Images