Display device and method of driving the same

Abstract

A display device and a method for driving the display device are provided. The display device includes: a display panel including a plurality of pixels; a controller for dividing the display panel into a plurality of regions, compensating image data provided from the outside based on a data compensation value set for each of the plurality of regions, and providing the compensated image data to the display panel; and an initialization power supply for supplying an initialization power supply voltage to the display panel, wherein the data compensation value is set for each of the plurality of regions of the display panel based on a difference between a target initialization power supply voltage and the initialization power supply voltage, wherein the target initialization power supply voltage is a voltage configured to allow any region to emit light at a target brightness for sensing image data.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0030734 filed on March 18, 2019, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Embodiments of the present disclosure relate to a display device and a method for driving the display device. Background Art

[0003] Each pixel of the display device includes a plurality of transistors, a storage capacitor and an organic light emitting element. Due to the threshold voltage deviation of the transistor, even if the same data voltage is applied, the output level of the brightness of the pixel is different, and the user of the display device sees stains.

[0004] In order to prevent staining, efforts may be made to compensate for the threshold voltage. However, in a large display device of a high-speed driving type, it may be difficult to sufficiently compensate for the threshold voltage of all pixels of the display panel.

[0005] A technique for compensating an image by compensating for a threshold voltage deviation of a driving transistor may be used. However, in a display device which is large and in which a high-speed driving method is used, it may be difficult to sufficiently compensate for the threshold voltages of all pixels of a display panel.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background technology and therefore it may contain information that does not constitute the prior art. Summary of the invention

[0007] Some example embodiments of the present disclosure may include a display device capable of accurately displaying a gray scale according to a data signal by compensating for a threshold voltage of a driving transistor and a method of driving the display device.

[0008] Some example embodiments of the present disclosure may include a display device and a method of driving the display device, in which a display panel is divided into a plurality of regions according to a threshold voltage of a driving transistor, and the threshold voltage of the driving transistor is compensated for each region.

[0009] However, it should be understood that aspects of the present disclosure may not be limited to the aforementioned characteristics, but may be variously extended without departing from the spirit and scope of the present disclosure.

[0010] According to some example embodiments, a display device includes: a display panel including a plurality of pixels; a controller for dividing the display panel into a plurality of regions, compensating image data provided from the outside based on a data compensation value set for each of the plurality of regions, and providing the compensated image data to the display panel; and an initialization power supply for supplying an initialization power supply voltage to the display panel, wherein a data compensation value is set for each of the plurality of regions of the display panel based on a difference between a target initialization power supply voltage and the initialization power supply voltage, wherein the target initialization power supply voltage is a voltage configured to allow any region to emit light at a target brightness for sensing image data.

[0011] According to some example embodiments, the controller may supply sensing image data and a sensing initialization power supply voltage to the display panel, and may measure a target initialization power supply voltage by analyzing brightness of an image displayed on the display panel in response to the sensing image data and the sensing initialization power supply voltage.

[0012] According to some example embodiments, the controller may adjust a sensing initialization power supply voltage for each of a plurality of pixels so that the pixel emits light at a target brightness under the adjusted sensing initialization power supply voltage, and determine the adjusted sensing initialization power supply voltage as a target initialization power supply voltage for the pixel.

[0013] According to some example embodiments, the controller may set a voltage satisfying a condition at which all of the plurality of pixels emit light at a target brightness, among target initialization power supply voltages of the plurality of pixels, as the initialization power supply voltage.

[0014] According to some example embodiments, the controller may divide the plurality of pixels into the plurality of regions based on a level of a difference between the initialization power supply voltage and the target initialization power supply voltage.

[0015] According to some example embodiments, the plurality of regions may be classified into any one of a pixel unit including a plurality of pixels, a pixel column unit, a pixel row unit, and a matrix block unit.

[0016] According to some example embodiments, the controller may set one of a minimum value, an average value, and a maximum value of target initialization power supply voltages of a plurality of pixels in one of the plurality of regions as the target initialization power supply voltage of the region.

[0017] According to some example embodiments, the sensing image data is black image data, and the target luminance is black luminance.

[0018] A method for driving a display device according to some example embodiments of the present disclosure includes: measuring a target initialization power supply voltage for each of a plurality of pixels constituting a display panel, wherein the target initialization power supply voltage is a voltage that allows the pixel to emit light at a target brightness of arbitrary sensed image data; dividing the display panel into a plurality of regions based on the target initialization power supply voltage; setting a data compensation value for each of the plurality of regions; compensating image data provided from the outside based on the data compensation value; and supplying the compensated image data and the initialization power supply voltage to the display panel, wherein the data compensation value is set for each of the plurality of regions based on a difference between the target initialization power supply voltage and the initialization power supply voltage.

[0019] According to some example embodiments, the step of measuring a target initialization power supply voltage may include: supplying sensing image data and a sensing initialization power supply voltage to a display panel; analyzing a brightness of an image displayed on the display panel in response to the sensing image data and the sensing initialization power supply voltage; and adjusting the sensing initialization power supply voltage for each of the plurality of pixels so that the pixel emits light with a target brightness under the adjusted sensing initialization power supply voltage, and determining the adjusted sensing initialization power supply voltage as the target initialization power supply voltage for the pixel.

[0020] According to some example embodiments, the method may further include, after measuring the target initialization power supply voltage, setting a voltage among the target initialization power supply voltages of the plurality of pixels that satisfies the following condition as the initialization power supply voltage at which all of the plurality of pixels emit light at the target brightness.

[0021] According to some example embodiments, dividing the display panel into the plurality of regions may include dividing the plurality of pixels into the plurality of regions based on a level of a difference between the initialization power supply voltage and the target initialization power supply voltage.

[0022] According to some example embodiments, the plurality of regions may be classified into any one of a pixel unit including a plurality of pixels, a pixel column unit, a pixel row unit, and a matrix block unit.

[0023] According to some example embodiments, measuring the target initialization power supply voltage may include setting one of a minimum value, an average value, and a maximum value of target initialization power supply voltages of pixels included in one of the plurality of regions as the target initialization power supply voltage of the region.

[0024] According to some example embodiments, the sensing image data may be black image data, and the target luminance may be black luminance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1is a block diagram illustrating a display device according to some example embodiments of the present disclosure.

[0026] Figure 2 It is shown Figure 1 A circuit diagram of an example of a pixel is shown in FIG.

[0027] Figure 3 It shows the input to Figure 2 : is a timing diagram of the pixel driving signal shown in .

[0028] Figure 4 is shown in more detail Figure 1 Block diagram of the controller.

[0029] Figure 5 is a flowchart of a method of driving a display device according to some example embodiments of the present disclosure. DETAILED DESCRIPTION

[0030] Hereinafter, aspects of some exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Like reference numerals represent like elements throughout.

[0031] Figure 1 is a block diagram illustrating a display device according to some example embodiments of the present disclosure.

[0032] Reference Figure 1 The display device 100 according to some example embodiments of the present disclosure includes a display panel 110 including a plurality of pixels PX, a scan driver 120, a data driver 130, a controller 140, and an initialization power supply 150. The display device 100 may be a device configured to output an image based on image data (e.g., first image data DATA1) provided from the outside. For example, the display device 100 may be an organic light emitting display device (OLED).

[0033] The display panel 110 may include a plurality of pixels PX (or sub-pixels) in a region where a plurality of scan lines S1 to Sn and a plurality of data lines D1 to Dm intersect each other. Here, n and m may be integers greater than or equal to 2. Each of the pixels PX may emit light based on a scan signal supplied to the plurality of scan lines S1 to Sn and a data signal supplied to the plurality of data lines D1 to Dm. In addition, the pixel PX may receive a high potential power voltage ELVDD, a low potential power voltage ELVSS, and an initialization power voltage Vint.

[0034] Will refer to Figure 2 The configuration of the pixel PX is described in more detail.

[0035] The scan driver 120 may generate a scan signal based on the scan driving control signal SCS. That is, the scan driver 120 may supply the scan signal to the pixel PX through the scan lines S1 to Sn during the display period.

[0036] The scan driving control signal SCS may be supplied from the controller 140 to the scan driver 120. The scan driving control signal SCS may include a start pulse and a clock signal. The scan driver 120 may include a shift register configured to sequentially generate scan signals corresponding to the start pulse and the clock signal.

[0037] The data driver 130 may generate a data signal based on the data drive control signal DCS and image data (e.g., second image data DATA2). The data driver 130 may supply the data signal generated based on the data drive control signal DCS to the display panel 110 during a display period in one frame. That is, the data driver 130 may supply the data signal to the pixel PX through the data lines D1 to Dm. The data drive control signal DCS may be supplied from the controller 140 to the data driver 130.

[0038] According to some example embodiments of the present disclosure, before image data (e.g., second image data DATA2) is applied to the data driver 130, black image data BDATA may be applied to the data driver 130 to determine a data compensation value for the pixel PX of the display panel 110. The data driver 130 may transmit a data signal corresponding to the black image data BDATA to the pixel PX of the display panel 110. For example, the black image data BDATA may be image data that causes the pixel PX of the display panel 110 to display black brightness.

[0039] The controller 140 may control operations of the scan driver 120, the data driver 130, and the initialization power supply 150. The controller 140 may generate a scan drive control signal SCS, a data drive control signal DCS, and an initialization control signal ICS, and may control the scan driver 120, the data driver 130, and the initialization power supply 150, respectively, based on the generated signals.

[0040] According to some example embodiments of the present disclosure, the controller 140 may perform brightness sensing for each pixel PX in order to adaptively determine the data compensation value for the region of the display panel 110. Specifically, the controller 140 may supply a data signal corresponding to the black image data BDATA to the pixel PX through the data driver 130, and may supply a sensing initialization power supply voltage SVint to the pixel PX through the initialization power supply 150.

[0041] While supplying the data signal corresponding to the black image data BDATA, the controller 140 may determine the actual brightness of each pixel PX for the black image data BDATA from the sensing information SI fed back from each pixel PX. While supplying the data signal corresponding to the black image data BDATA, the controller 140 may determine the black initialization power supply voltage by changing the sensing initialization power supply voltage SVint, at which the actual brightness of all pixels PX becomes the target brightness corresponding to the black image data BDATA. The controller 140 may determine the initialization power supply voltage Vint as the final initialization power supply voltage Vint for the display panel 110. The initialization power supply voltage Vint determined by the controller 140 may be later supplied to the pixel PX through the initialization power supply 150.

[0042] According to some example embodiments, since the characteristics (e.g., threshold voltage) of the pixels PX may be different, the initialization power supply voltage (e.g., black initialization power supply voltage) at which the actual brightness becomes the target brightness based on the black image data BDATA may be different according to the pixels PX. Therefore, when the display device 100 operates at the determined initialization power supply voltage Vint, brightness degradation may occur at the pixels PX in which the black initialization power supply voltage is lower than the determined initialization power supply voltage Vint.

[0043] In the present disclosure, in order to prevent or reduce the above-mentioned brightness degradation, a data compensation value for image data (e.g., first image data DATA1) may be determined based on the difference between the determined initialization power supply voltage Vint and the black initialization power supply voltage. For example, the controller 140 may divide the display panel 110 into a plurality of regions, and may determine a data compensation value corresponding to each region. Here, the data compensation value may represent an offset value to be applied to the image data so that the pixel PX emits light at a target brightness for any image data.

[0044] Here, in each of the plurality of regions, the initialization power supply voltage for the region has a specific range of difference from the initialization power supply voltage Vint determined as above. The controller 140 may divide the display panel 110 into a plurality of regions based on the black initialization power supply voltage of the pixel PX determined in the process of determining the above-mentioned initialization power supply voltage Vint. According to some example embodiments, the controller 140 may determine the data compensation value based on the difference between the average black initialization power supply voltage, the minimum black initialization power supply voltage, or the maximum black initialization power supply voltage of the pixel PX included in each region and the determined initialization power supply voltage Vint.

[0045] According to some example embodiments, the plurality of regions may be defined as a pixel row unit, a block unit including a plurality of pixel rows, a pixel column unit, a block unit including a plurality of pixel columns, or a matrix block unit including a plurality of pixel rows and a plurality of pixel columns. However, the technical spirit of the present disclosure is not limited thereto, and according to some example embodiments, the plurality of regions may be defined as a unit of a pixel PX, for example, a unit of a single pixel PX.

[0046] The controller 140 may store the data compensation values ​​determined for the plurality of regions in the form of a lookup table (LUT), etc. Thereafter, when image data (e.g., first image data DATA1) is provided from the outside, the controller 140 may correct the image data based on the pre-stored data compensation value, and may transmit the corrected image data (e.g., second image data DATA2) to the data driver 130. According to some example embodiments, the controller 140 may store the difference between the determined initialization power supply voltage Vint and the black initialization power supply voltage of each region in a lookup table, and may determine the data compensation value in real time by referring to the lookup table.

[0047] As described above, in the present disclosure, a data compensation value for each of a plurality of regions on the display panel 110 can be adaptively determined based on a difference between an initialization power supply voltage Vint of the display panel 110 and a black initialization power supply voltage of each pixel PX, thereby allowing grayscale to be correctly displayed in all pixels PX of the display panel 110 and simultaneously preventing brightness degradation.

[0048] Figure 2 It is shown Figure 1 For the convenience of description, Figure 2 The pixel PX connected to the i-th scan line Si, the i-1-th scan line Si-1, the i-2-th scan line Si-2, and the j-th data line Dj is shown.

[0049] Reference Figure 2 , the pixel PX may include first to fourth transistors T1 to T4, a storage capacitor Cst, and an organic light emitting diode OLED. The pixel PX may be connected to the scan driver 120 through the scan line Si (and the scan lines Si-1 and Si-2), and may be connected to the data driver 130 through the data line Dj.

[0050] An anode of the organic light emitting diode OLED may be connected to the second electrode of the first transistor T1, and a cathode of the organic light emitting diode OLED may be connected to the low potential power voltage ELVSS. The organic light emitting diode OLED generates light with a specific brightness in response to the amount of current supplied from the first transistor T1.

[0051] The first transistor (e.g., driving transistor) T1 includes a gate electrode connected to the first node N1, a first electrode connected to a high potential power voltage ELVDD supplied from the outside, and a second electrode connected to the anode of the organic light emitting diode OLED. When the first transistor T1 is turned on, the first transistor T1 transmits a driving current to the organic light emitting diode OLED according to a data signal (or data voltage) applied to the first node N1, and enables the organic light emitting diode OLED to emit light at a specific brightness.

[0052] The second transistor (e.g., a switching transistor) T2 includes a gate electrode connected to the i-th scan line Si, a first electrode connected to the data line Dj, and a second electrode connected to the first node N1. When the second transistor T2 is turned on, the second transistor T2 can transmit a data voltage according to a data signal from the data line Dj to the first node N1 connected to the gate electrode of the first transistor T1.

[0053] The third transistor (e.g., threshold voltage compensation transistor) T3 includes a gate electrode connected to the i-1th scan line Si-1, a first electrode connected to the first node N1, and a second electrode connected to the second electrode of the first transistor T1. The i-1th scan line Si-1 may transmit a scan signal of a previous pixel row so as to control compensation of the threshold voltage of the first transistor T1.

[0054] According to some example embodiments, when a compensation control signal for threshold voltage compensation is supplied to the gate electrode of the third transistor T3, the switch operation may be controlled in response to the compensation control signal. For example, before the i-th scan signal is transmitted through the i-th scan line Si, the third transistor T3 is turned on in response to the i-1-th scan signal applied through the i-1-th scan line Si-1, and the gate electrode and the second electrode of the first transistor T1 are connected to each other to diode-connect the first transistor T1. In some embodiments, a voltage corresponding to the threshold voltage of the first transistor T1 is stored in the storage capacitor Cst. Thereafter, when a data signal is supplied, the threshold voltage pre-stored in the storage capacitor Cst and the voltage corresponding to the data signal may be supplied to the gate electrode of the first transistor T1, thereby compensating for the threshold voltage deviation.

[0055] The fourth transistor (e.g., initialization transistor) T4 may include a gate electrode connected to the i-2 th scan line Si-2, a first electrode connected to the initialization power supply voltage Vint, and a second electrode connected to the first node N1. The fourth transistor T4 may be turned on in response to the i-2 th scan signal supplied to the i-2 th scan line Si-2, and may apply the initialization power supply voltage Vint to the gate electrode of the first transistor T1 to initialize a previous data voltage applied to the gate electrode of the first transistor T1.

[0056] The storage capacitor Cst includes one electrode connected to the high potential power supply voltage ELVDD connected to the first electrode of the first transistor T1 and another electrode connected to the first node N1. The storage capacitor Cst charges a voltage according to a difference between voltages applied to the two electrodes of the storage capacitor Cst. For example, the storage capacitor Cst may maintain a voltage corresponding to a difference between a voltage changed according to a change in a voltage applied to the first node N1 and the high potential power supply voltage ELVDD during a certain period of time.

[0057] The anode of the organic light emitting diode OLED is connected to the second electrode of the first transistor T1, and the cathode of the organic light emitting diode OLED is connected to the low potential power voltage ELVSS. The organic light emitting diode OLED can emit light in response to the amount of current flowing from the high potential power voltage ELVDD to the low potential power voltage ELVSS through the first transistor T1.

[0058] Figure 2 , an example in which the first to fourth transistors T1 to T4 are p-type transistors is shown, but the technical spirit of the present disclosure is not limited thereto. That is, according to some example embodiments, at least some or all of the first to fourth transistors T1 to T4 may be replaced with n-type transistors, and Figure 2 The circuit of the pixel PX shown in FIG. 1 may be variously modified to correspond to an n-type transistor.

[0059] Figure 3 It shows the input to Figure 2 : is a timing diagram of the pixel driving signal shown in .

[0060] Refer to Figure 2 and Figure 3 , the i-2 th scan signal S(i-2) having a gate-on level may be applied to the gate electrode of the fourth transistor T4 at time t1. Then, the fourth transistor T4 is turned on, and the initialization power supply voltage Vint is applied to the first node N1.

[0061] The storage capacitor Cst is charged to a voltage value corresponding to the previous data voltage and then gradually discharged by the initialization power supply voltage Vint applied to the other electrode of the storage capacitor Cst connected to the first node N1. That is, the charging voltage of the storage capacitor Cst is changed from the voltage corresponding to the previous data voltage to a voltage corresponding to the difference between the voltages applied to both ends of the storage capacitor Cst, for example, a voltage corresponding to the difference between the high potential power supply voltage ELVDD and the initialization power supply voltage Vint.

[0062] The i-1th scan signal S(i-1) having a gate-on level is applied to the gate electrode of the third transistor T3 at time t2. When the third transistor T3 is turned on in response to the i-1th scan signal S(i-1), the first transistor T1 is diode-connected. Then, the threshold voltage of the first transistor T1 is applied to the first node N1.

[0063] The storage capacitor Cst storing the voltage corresponding to the initialization power supply voltage Vint is discharged to a voltage value corresponding to the threshold voltage of the first transistor T1. In the present disclosure, the compensation time for compensating the threshold voltage represents the time when the storage capacitor Cst is charged to the voltage corresponding to the initialization power supply voltage Vint at time t1 and discharged to the voltage corresponding to the threshold voltage of the first transistor T1 at time t2.

[0064] At time t3, the i-th scan signal S(i) having a gate-on level is applied to the gate electrode of the second transistor T2. Then, the second transistor T2 is turned on, and a data voltage corresponding to the data signal applied to the data line Dj is transmitted to the first node N1. The storage capacitor Cst stores a voltage value corresponding to the data voltage. Here, the data voltage may be, for example, a voltage corresponding to the second image data DATA2 supplied from the controller 140.

[0065] Thereafter, when the i-th scan signal S(i) is switched to the gate-off level, the second transistor T2 is turned off. Then, the first transistor T1 may transmit a driving current to the organic light emitting diode OLED, wherein the driving current corresponds to a voltage corresponding to a difference between a voltage of a gate electrode and a voltage of a source electrode of the first transistor T1, for example, a voltage held in the storage capacitor Cst.

[0066] According to some example embodiments of the present disclosure, the data signal supplied to the pixel PX may be a signal generated based on the second image data DATA2. The second image data DATA2 may be generated by applying a data compensation value determined by the controller 140 to the original image data (e.g., the first image data DATA1) supplied from the outside. The data compensation value may be set for each of a plurality of regions on the display panel 110 based on the difference between the initialization power supply voltage Vint of the display panel 110 and the black initialization power supply voltage. That is, the data signal supplied to the pixel PX may be generated based on the second image data DATA2, which is generated by applying a set or predetermined data compensation value to the first image data DATA1 corresponding to a region including the corresponding pixel PX among the plurality of regions of the display panel 110.

[0067] Figure 4 is shown in more detail Figure 1 Block diagram of the controller.

[0068] Reference Figure 4 , the controller 140 according to some example embodiments of the present disclosure includes an initialization power supply voltage determination unit 141 , a data compensation value determination unit 142 , a storage unit 143 , and an image data compensation unit 144 .

[0069] The initialization power supply voltage determination unit 141 may be connected to the display panel 110 and may measure a black initialization power supply voltage for a plurality of pixels PX included in the display panel 110 and may determine an initialization power supply voltage Vint of the display panel 110 based on the measurement result.

[0070] For example, the initialization power supply voltage determination unit 141 may supply a specific data signal and a sensing initialization power supply voltage SVint, which allows the display panel 110 to display a sensing image.

[0071] The sensed image is an image having the same grayscale information, which allows all pixels PX of the display panel 110 to emit light at the same specific target brightness. For example, the sensed image may be a black image, but is not limited thereto. The initialization power supply voltage determination unit 141 transmits the black image data BDATA to the data driver 130, and the data driver 130 transmits a data signal corresponding to the black image data BDATA to the data lines D1 to Dm connected to the pixels PX.

[0072] The sensing initialization power supply voltage SVint may be equally transmitted to all pixels PX through the initialization power supply 150 to initialize the driving current of the plurality of pixels PX of the display panel 110. There may be various methods of initializing the driving current of the pixels PX included in the display panel 110 according to the characteristics and type of the display panel 110, and thus the method of applying the sensing initialization power supply voltage SVint is not particularly limited.

[0073] According to some example embodiments of the present disclosure, when the pixel PX is a self-emissive element such as an organic light-emitting element, a sensing initialization power supply voltage SVint may be applied to a control element (eg, a driving transistor) to initialize a driving current having a specific value transmitted to the organic light-emitting element.

[0074] When the data signal corresponding to the black image data BDATA and the sensing initialization power voltage SVint are applied to the display panel 110, the display panel 110 may be initialized by the sensing initialization power voltage SVint, and then a black image may be displayed. The display panel 110 is driven by a separately supplied driving power voltage, initializes each pixel PX using the sensing initialization power voltage SVint supplied by the initialization power voltage determination unit 141, and then displays a black image based on the black image data BDATA.

[0075] The initialization power supply voltage determination unit 141 receives sensing information SI about a black image displayed on the display panel 110. That is, the initialization power supply voltage determination unit 141 analyzes the brightness of the black image displayed by the display panel 110. When each pixel PX of the display panel 110 emits light, the initialization power supply voltage determination unit 141 determines a value of an actual brightness for a target brightness (e.g., black brightness) corresponding to the black image data BDATA. The target brightness refers to the brightness when the pixel PX ideally emits light according to the black grayscale.

[0076] The initialization power supply voltage determination unit 141 repeatedly analyzes the brightness of the display panel 110 while adjusting the sensing initialization power supply voltage SVint. During the repeated analysis, all driving conditions of the display panel 110 except the sensing initialization power supply voltage SVint may remain unchanged. The initialization power supply voltage determination unit 141 may measure a black initialization power supply voltage (e.g., a target initialization power supply voltage) by brightness analysis, wherein the black initialization power supply voltage is a voltage at which the actual brightness of each pixel PX becomes a target brightness related to the black image data BDATA. That is, the sensing initialization power supply voltage is adjusted for each of the plurality of pixels, and when the pixel emits light at the target brightness under the adjusted sensing initialization power supply voltage SVint, the initialization power supply voltage determination unit 141 determines the adjusted sensing initialization power supply voltage SVint as the black initialization power supply voltage of the pixel.

[0077] When the display panel 110 actually displays an image according to external image data, the initialization power supply voltage determination unit 141 sets an initialization power supply voltage Vint for compensating for the threshold voltage distribution of the plurality of driving transistors. The initialization power supply voltage Vint may be set to a black initialization power supply voltage corresponding to when the actual brightness for all pixels PX of the display panel 110 becomes the target brightness for the black image data BDATA. The initialization power supply voltage Vint may have the lowest value among the black initialization power supply voltages of the pixels PX, but the present disclosure is not limited thereto.

[0078] The initialization power voltage Vint determined by the initialization power voltage determination unit 141 may be supplied to the display panel 110 through the initialization power supply 150 .

[0079] The data compensation value determining unit 142 may divide the display panel 110 into a plurality of regions based on the initialization power supply voltage Vint determined by the initialization power supply voltage determining unit 141 and an actual initialization power supply voltage (e.g., a black initialization power supply voltage) of each pixel PX measured by the initialization power supply voltage determining unit 141. The data compensation value determining unit 142 may determine a data compensation value corresponding to each divided region.

[0080] According to some example embodiments, grayscale defects may occur in a black image according to the black image data BDATA because the threshold voltage characteristics of the driving transistors of the pixels PX in the display panel 110 are different from each other. Therefore, a deviation may occur between the black initialization power supply voltage of each pixel PX and the set initialization power supply voltage Vint.

[0081] The data compensation value determination unit 142 may determine a specific critical range relative to the initialization power supply voltage Vint. When the black initialization power supply voltage deviates from the critical range, the data compensation value determination unit 142 may group the corresponding pixels PX into pixel units, pixel row units, pixel column units, or matrix block units. That is, the data compensation value determination unit 142 classifies the level of the difference between the actual black initialization power supply voltage and the set initialization power supply voltage Vint, and groups the pixels PX into specific groups. The data compensation value determination unit 142 regards the level of the difference between the black initialization power supply voltage and the set initialization power supply voltage Vint of the pixels PX belonging to each group in the specific group as being similar to each other.

[0082] The data compensation value determination unit 142 may determine the data compensation value of the corresponding region for each group (e.g., each region). That is, when the display panel 110 is driven with the set initialization power supply voltage Vint, the data compensation value determination unit 142 may determine the offset value (voltage value) to be applied to the image data so that the pixel PX emits light at the target brightness for any image data.

[0083] The storage unit 143 may store the data compensation value for each region determined by the data compensation value determination unit 142 in the form of a lookup table. According to some example embodiments, the storage unit 143 may store the difference between the black initialization power voltage of each region and the determined initialization power voltage Vint in a lookup table or the like.

[0084] When first image data DATA1 is received from the outside, the image data compensation unit 144 may generate second image data DATA2 by correcting the first image data DATA1 based on the data compensation value stored in the storage unit 143. The image data compensation unit 144 may obtain a data compensation value from the lookup table to correspond to a region of the display panel 110 in which the first image data DATA1 is to be displayed. The image data compensation unit 144 may generate second image data DATA2 by applying the obtained data compensation value to the first image data DATA1.

[0085] According to some example embodiments, when the storage unit 143 stores the difference between the black initialization power voltage and the initialization power voltage Vint of each area in the storage table, the image data compensation unit 144 can determine the data compensation value in real time based on the difference value obtained from the lookup table, and can also generate the second image data DATA2 using the determined data compensation value.

[0086] Storage unit 143 is Figure 4 The storage unit 143 is shown as a component provided in the controller 140, but the technical spirit of the present disclosure is not limited thereto. That is, according to some example embodiments, the storage unit 143 may be provided separately from the controller 140 in the display device 100, or may be provided separately outside the display device 100.

[0087] Figure 5 is a flowchart of a method of driving a display device according to some example embodiments of the present disclosure.

[0088] Reference Figure 5 , the display device 100 may provide sensing image data and a sensing initialization power supply voltage SVint to the display panel 110 (501). According to some example embodiments, the sensing image data may be black image data BDATA.

[0089] When the black image data BDATA and the sensing initialization power supply voltage SVint are supplied, the display panel 110 may display a black image. At this time, the display device 100 may perform a brightness analysis on the display panel 110 to determine a black initialization power supply voltage for the pixel PX (502). For example, the display device 100 may measure a black initialization power supply voltage at which the actual brightness of the display panel 110 becomes black brightness while adjusting the sensing initialization power supply voltage SVint supplied to the display panel 110.

[0090] The display device 100 may set the initialization power supply voltage Vint of the display panel 110 based on the black initialization power supply voltage measured for the pixel PX (503). For example, the display panel 110 may set the initialization power supply voltage when the actual brightness of all pixels PX of the display panel 110 becomes black brightness as the final initialization power supply voltage Vint. According to some example embodiments, the initialization power supply voltage Vint may have the lowest value among the black initialization power supply voltages of the pixel PX, but the present disclosure is not limited thereto.

[0091] The display device 100 may set a data compensation value for each of a plurality of regions on the display panel 110 based on a difference between a black initialization power supply voltage measured for the pixel PX and a set initialization power supply voltage Vint (504). The display device 100 may divide the display panel 110 into a plurality of regions according to a difference between a black initialization power supply voltage measured for the pixel PX and a set initialization power supply voltage Vint. The display device 100 may set a data compensation value for each region according to a difference between the black initialization power supply voltage and the initialization power supply voltage Vint for each region. According to some example embodiments, the display device 100 may store the set data compensation value for each region in a lookup table or the like.

[0092] The display device 100 may compensate the image data input from the outside using the set data compensation value (505). For example, the display device 100 may determine whether the pixel PX on which the corresponding image data is to be displayed is included in any area among the plurality of areas of the display panel 110, and may compensate the image data by applying the preset data compensation value corresponding to the corresponding area to the image data.

[0093] The display device 100 may supply the compensated image data and the initialization power supply voltage Vint to the display panel 110 (506). As described above, in the present disclosure, the image data is compensated to correspond to the difference between the initialization power supply voltage Vint applied to the display panel 110 and the actual black initialization power supply voltage of each area of ​​the display panel 110, thereby preventing or reducing the brightness degradation caused by the threshold voltage deviation of the pixel PX to display a high-quality image.

[0094] According to the display device and the method of driving the display device according to the present disclosure, a threshold voltage deviation of a driving transistor of a pixel included in a display panel of the display device may be effectively compensated.

[0095] Furthermore, according to the display device and the method of driving the display device according to the present disclosure, it is possible to improve the image of a display device that is large-scale and driven at a high speed without adding new components.

[0096] It will be appreciated by those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the spirit or essential characteristics of the present disclosure. Therefore, it should be understood that the above exemplary embodiments are exemplary in all respects and not restrictive. The scope of the present disclosure is defined by the claims set forth rather than by the detailed description above. All changes or modifications falling within the meaning and scope of the claims and their equivalents should be interpreted as being included within the scope of the present disclosure.

[0097] It will be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the spirit and scope of the inventive concept, the first element, first component, first region, first layer or first part discussed herein may be named as the second element, second component, second region, second layer or second part.

[0098] For ease of description, spatially relative terms such as "under", "below", "below", "below", "above", "on", etc. may be used here to describe the relationship of one element or feature to another or more elements or features as shown in the drawings. It will be understood that, in addition to the orientation depicted in the drawings, the spatially relative terms are intended to include different orientations of the device in use or operation. For example, if the device in the drawings is turned over, the elements described as "under", "under" or "below" other elements or features will then be positioned as "above" the other elements or features. Therefore, the example terms "under" and "below" may include both above and below orientations. The device may be positioned otherwise (e.g., rotated 90 degrees or at other orientations), and the spatially relative descriptors used here should be interpreted accordingly. In addition, it will be understood that when a layer is referred to as "between" two layers, the layer may be the only layer between the two layers, or one or more intermediate layers may also be present.

[0099] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the inventive concept. As used herein, the terms "substantially," "approximately," and similar terms are used as approximate terms rather than terms of degree, and are intended to illustrate the inherent deviations in measured or calculated values ​​that would be recognized by those of ordinary skill in the art.

[0100] As used herein, unless the context clearly indicates otherwise, the singular forms "one" and "one (kind / person)" are also intended to include plural forms. It will also be understood that when the terms "including" and / or "comprising" are used in this specification, the characteristics, wholes, steps, operations, elements and / or components are described, but the existence or addition of one or more other characteristics, wholes, steps, operations, elements, components and / or their groups are not excluded. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. Such as "at least one (person / person) in ... ", when being located after a column of elements (elements), modify the entire column of elements (elements), rather than modifying the individual elements (elements) in the column. In addition, when describing the embodiment of the inventive concept, the use of "can" refers to "one or more embodiments of the present disclosure". In addition, the term "exemplary" is intended to represent an example or description. As used herein, the terms "use", "being used" and "used" can be considered to be synonymous with the terms "utilize", "being utilized" and "utilized", respectively.

[0101] It will be understood that when an element or layer is referred to as being “on,” “connected to,” “bound to,” or “adjacent to” another element or layer, the element or layer may be directly on, directly connected to, directly bound to, or directly adjacent to the other element or layer, or one or more intervening elements or layers may be present. In contrast, when an element or layer is referred to as being “directly on,” “directly connected to,” “directly bound to,” or “directly adjacent to” another element or layer, there are no intervening elements or layers.

[0102] Any numerical range stated here is intended to include all sub-ranges of the same numerical precision within the stated range. For example, the range of "1.0 to 10.0" is intended to include all sub-ranges between the stated minimum value 1.0 and the stated maximum value 10.0 (including the stated minimum value 1.0 and the stated maximum value 10.0), that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit stated here is intended to include all smaller numerical limits contained therein, and any minimum numerical limit stated in this specification is intended to include all larger numerical limits contained therein.

Claims

1. A display device, comprising: A display panel including a plurality of pixels; a controller configured to divide the display panel into a plurality of regions, compensate image data provided from the outside based on a data compensation value set for each of the plurality of regions, and provide the compensated image data to the display panel; as well as an initialization power supply configured to supply the same initialization power supply voltage to each of the plurality of regions of the display panel, wherein the data compensation value is set for each of the plurality of regions of the display panel based on a difference between a target initialization power supply voltage and the initialization power supply voltage, wherein the target initialization power supply voltage of any region of the plurality of regions is a voltage configured to allow the region to emit light at a target brightness for sensing image data, The controller is further configured to set a voltage among the target initialization power supply voltages of the plurality of pixels that satisfies the following condition as the initialization power supply voltage: at the voltage, all the pixels among the plurality of pixels emit light at the target brightness.

2. The display device according to claim 1, wherein: The controller is configured to supply the sensing image data and a sensing initialization power supply voltage to the display panel, and measure the target initialization power supply voltage by analyzing brightness of an image displayed on the display panel in response to the sensing image data and the sensing initialization power supply voltage.

3. The display device according to claim 2, wherein: The controller is also configured to adjust the sensing initialization power supply voltage for each of the plurality of pixels so that the pixel emits light at the target brightness under the adjusted sensing initialization power supply voltage, and determine the adjusted sensing initialization power supply voltage as the target initialization power supply voltage of the pixel.

4. The display device according to claim 1, wherein: The controller is further configured to divide the plurality of pixels into the plurality of regions based on a level of the difference between the initialization power supply voltage and the target initialization power supply voltage.

5. The display device according to claim 4, wherein: The plurality of regions are classified into any one of a pixel unit including at least one pixel of the plurality of pixels, a pixel column unit, a pixel row unit, and a matrix block unit.

6. The display device according to claim 4, wherein: The controller is further configured to set one of a minimum value, an average value, and a maximum value of target initialization power supply voltages of pixels in one of the plurality of regions as the target initialization power supply voltage of the region.

7. The display device according to claim 1, wherein: The sensed image data is black image data, and the target luminance is black luminance.

8. A method for driving a display device, the method comprising: measuring a target initialization power supply voltage for each of a plurality of pixels constituting a display panel, wherein the target initialization power supply voltage is a voltage that allows the pixel to emit light at a target brightness of arbitrary sensed image data; dividing the display panel into a plurality of regions based on the target initialization power supply voltage; setting a data compensation value for each of the plurality of regions; compensating image data provided from the outside based on the data compensation value; and supplying compensated image data and an initialization power supply voltage to the display panel, wherein the data compensation value is set for each of the plurality of regions based on a difference between the target initialization power supply voltage and the initialization power supply voltage, wherein the initialization power supply voltage is the same initialization power supply voltage for each of the plurality of regions of the display panel, and The initialization power supply voltage is set to a voltage among target initialization power supply voltages of the plurality of pixels that satisfies the following condition: at the voltage, all of the plurality of pixels emit light at the target brightness.

9. The method according to claim 8, wherein: The step of measuring the target initialization power supply voltage comprises: supplying the sensing image data and a sensing initialization power supply voltage to the display panel; analyzing a brightness of an image displayed on the display panel in response to the sensing image data and the sensing initialization power supply voltage; and The sensing initialization power supply voltage is adjusted for each of the plurality of pixels so that the pixel emits light at the target brightness under the adjusted sensing initialization power supply voltage, and the adjusted sensing initialization power supply voltage is determined as the target initialization power supply voltage of the pixel.

Images