Display device and driving method thereof

Abstract

The invention relates to a display device and a driving method thereof. A display device according to an embodiment of the present disclosure includes: a display panel including a plurality of sub-pixels; a driver circuit, which is configured to drive the display panel; and a sensing circuit that senses an electrical characteristic of a sensing area of the display panel to output sensing data, in which the driver circuit performs a sequence of changing a sensing current applied to the first power supply line until the sensing data falls within a target range in a sensing mode, and repeating the sequence for the sensing region.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10 - 2023 - 0187095, filed on December 20, 2023, which is incorporated herein by reference in its entirety as if fully set forth herein. Technical field

[0003] The present disclosure relates to a display device for afterimage compensation. Background art

[0004] Electroluminescent display devices have the advantages of high brightness, low driving voltage, ultra - thinness, and free form by using self - emitting elements.

[0005] To ensure long - term performance and reliability, an electroluminescent display device can compensate for afterimages by sensing and measuring the electrical characteristics of light - emitting elements when the light - emitting elements deteriorate.

[0006] An electroluminescent display device can sense the electrical characteristics of a sensing sub - pixel through a power line shared by the sensing sub - pixel and a non - sensing sub - pixel.

[0007] In an electroluminescent display device, a leakage current flowing through a non - sensing sub - pixel may cause a sensing error in the electrical characteristics of the sensing sub - pixel, which may distort afterimage compensation. Summary of the invention

[0008] One aspect of the present disclosure relates to providing a display device and a driving method thereof, which can improve afterimage compensation performance by minimizing the influence of leakage current, thereby improving the sensing accuracy of the electrical characteristics of light - emitting elements.

[0009] The problems to be solved by the embodiments of the present disclosure are not limited to those mentioned above. According to the following description, other problems not mentioned above will be apparent to those skilled in the art to which the technical concept of the present disclosure pertains.

[0010] A display device according to an embodiment of the present disclosure includes: a display panel including a plurality of sub - pixels; a driver circuit configured to drive the display panel; and a sensing circuit that senses the electrical characteristics of a sensing area of the display panel to output sensing data, wherein the driver circuit performs a sequence of changing a sensing current applied to a first power line until the sensing data falls within a target range in a sensing mode, and repeats the sequence for the sensing area.

[0011] A driving method of a display device according to an embodiment of the present disclosure includes: a step of sensing a sensing area of a display area using a first sensing current according to a first sensing sequence, a step of determining whether the first sensing data is distorted by comparing the first sensing data sensed according to the first sensing sequence of the current sensing mode with the previous sensing data of the previous sensing mode, a step of changing the first sensing current to a second sensing current when it is determined that the first sensing data is distorted, a step of sensing the sensing area of the display area using the second sensing current according to the second sensing sequence, and repeating a step of determining whether the second sensing data is distorted by comparing the second sensing data sensed according to the second sensing sequence with the previous sensing data of the previous sensing mode, and a step of calculating a compensation gain for a change in an electrical characteristic of a sensing sub-pixel in the sensing area based on the sensing data determined to be normal and storing the compensation gain in a memory when the first sensing data or the second sensing data is determined to be normal.

[0012] In addition to the above challenges, specific details according to various embodiments are included in the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings included to provide a further understanding of the present disclosure and incorporated into this application and constituting a part of this application illustrate embodiments of the present disclosure and, together with the description, are used to explain the principles of the present disclosure. In the drawings:

[0014] Figure 1 is a block diagram schematically showing the configuration of a display device according to an embodiment of the present disclosure.

[0015] Figure 2 is a schematic diagram of the configuration of a sub-pixel according to an embodiment of the present disclosure.

[0016] Figure 3 is an equivalent circuit showing the sub-pixel configuration according to an embodiment of the present disclosure.

[0017] Figure 4 is a diagram showing the driving waveform of a sub-pixel according to an embodiment of the present disclosure.

[0018] Figure 5 is a diagram showing the sensing path of a sensing sub-pixel in a display device according to an embodiment of the present disclosure.

[0019] Figure 6 is a diagram of a sensing area of a display device according to an embodiment of the present disclosure.

[0020] Figures 7 to 9It is a diagram showing a color-specific sensing path in a display device according to an embodiment of the present disclosure.

[0021] Figure 10 It is a diagram showing the flow of leakage current in a display device according to an embodiment of the present disclosure.

[0022] Figure 11 It is a graph showing the current-voltage change characteristics of a light-emitting element due to the influence of leakage current according to an embodiment of the present disclosure.

[0023] Figure 12 It is a flowchart showing a method of sensing mode for driving a display device according to an embodiment of the present disclosure.

[0024] Figure 13 It is a graph showing the change in the current-voltage characteristics of a light-emitting element in response to a change in the sensing current according to an embodiment of the present disclosure.

[0025] Figure 14 It is a waveform diagram showing an exemplary sensing sequence of a display device according to an embodiment of the present disclosure.

[0026] Figure 15 and Figure 16 It is a diagram showing the brightness change process of an image pattern that can confirm the sensing behavior in response to a change in the sensing current of a display device according to an embodiment of the present disclosure. Detailed Description

[0027] The advantages, features, and methods of implementing the present disclosure will be clarified by the following aspects described with reference to the accompanying drawings. However, the present disclosure may be implemented in different forms and should not be construed as limited to the aspects set forth herein. On the contrary, these aspects are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0028] The shapes, sizes, ratios, angles, and quantities disclosed in the accompanying drawings for describing the aspects of the present disclosure are merely examples, and thus, the present disclosure is not limited to the details shown. Throughout the specification, like reference numerals denote like elements. In the following description, when the detailed description of related known functions or configurations is determined to unnecessarily obscure the focus of the present disclosure, the detailed description will be omitted. In the case of using "comprising", "having", and "including" described in this specification, another part may be added unless "only" is used. Unless otherwise stated, terms in the singular form may include the plural form.

[0029] When explaining an element, the element is interpreted as including an error range even though there is no explicit description.

[0030] When describing positional relationships, for example, when the positional relationship between two parts is described as "on", "above", "below", and "next", one or more other parts may be provided between the two parts unless more restrictive terms such as "just" or "directly" are used.

[0031] When describing temporal relationships, for example, when the chronological order is described as "after", "subsequently", "next", and "before", discontinuous cases may be included unless more restrictive terms such as "just", "immediately", or "directly" are used.

[0032] It should be understood that although terms such as "first" and "second" may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present disclosure, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element.

[0033] When describing the elements of the present disclosure, terms such as "first", "second", "A", "B", "(a)", "(b)", etc. may be used. These terms are intended to identify the corresponding elements from other elements, and the basis, order, sequence, or quantity of the corresponding elements should not be defined or limited by these terms. With respect to the statement that an element or layer is "connected", "coupled", or "adhered" to another element or layer, the element or layer may not only be directly connected or adhered to another element or layer, but also be indirectly connected or adhered to another element or layer, where one or more intermediate elements or layers are "provided" between the element or layer, unless otherwise specified.

[0034] The term "at least one" should be understood to include any and all combinations of one or more of the associated listed elements. For example, the meaning of "at least one or more of the first element, the second element, and the third element" represents the combinations of two or more of the first element, the second element, and the third element and all the elements presented by the first element, the second element, or the third element.

[0035] The features of the various aspects of the present disclosure may be partially or wholly coupled or combined with each other, and may operate differently from each other and be technically driven, as can be fully understood by those skilled in the art. The aspects of the present disclosure may be carried out independently of each other, or may be carried out together in a mutually dependent relationship.

[0036] In the following, aspects of the present disclosure will be described with reference to the accompanying drawings. Since, for ease of description, the scale of each element shown in the drawings is different from the actual scale, the present disclosure is not limited to the shown scale. In addition, all components of each display device, display device, and display panel according to all aspects of the present disclosure may be operably coupled and configured.

[0037] Figure 1 is a block diagram schematically showing the configuration of a display device according to an embodiment of the present disclosure, Figure 2 is a diagram schematically showing the configuration of sub-pixels according to an embodiment of the present disclosure.

[0038] According to one embodiment, the display device 1000 may be an electroluminescent display, including an organic light emitting diode (OLED) display device, a quantum dot light emitting diode display device, or an inorganic light emitting diode display device. The display device 1000 according to one embodiment may be a micro light emitting diode display device.

[0039] Referring to Figure 1 , the display device 1000 may include a display panel 100 and a display driver circuit 900. The display driver circuit 900 may be connected to the host system 2000.

[0040] The display driver circuit 900 may include a gate driver 200, a data driver 300, a timing controller 400, a memory 500, a sensing circuit 600, and a power management circuit 700. In the display driver circuit 900, structures other than the sensing circuit 600 may be represented as a driver circuit.

[0041] The display panel 100 may be a rigid display panel or a deformable flexible display panel, such as a foldable, bendable, rollable, or stretchable display panel.

[0042] The display panel 100 may include a display area DA for displaying an image and a border area BZ: BZ1 to BZ4 surrounding the display area DA and provided on the periphery.

[0043] According to one embodiment, the display panel 100 may further include a touch sensor array provided in the display area DA to sense a touch of a user.

[0044] The display panel 100 may display an image using the display area DA in which a plurality of sub-pixels SP are arranged in a matrix form. The pixel matrix of the display area DA may include a plurality of pixel row lines and a plurality of pixel column lines. The plurality of pixel row lines include a plurality of sub-pixels SP arranged in a first direction X, and the plurality of pixel column lines include a plurality of sub-pixels SP arranged in a second direction Y.

[0045] The sub-pixel SP can be any one of a red sub-pixel that emits red light, a green sub-pixel that emits green light, and a blue sub-pixel that emits blue light. The sub-pixel SP can be a white sub-pixel that emits white light. The unit pixel can include at least two sub-pixels SP.

[0046] Reference Figure 2 , the sub-pixel SP can include a light-emitting element EL and a pixel circuit 10 that drives the light-emitting element EL.

[0047] A data voltage Vdata can be provided to the sub-pixel SP according to an embodiment from a data driver 300 through at least one data line 22. A scan signal SCAN can be provided to the sub-pixel SP from a gate driver 200 through at least one gate line 12, and a light emission control signal EM can be provided to the sub-pixel SP through at least one gate line 16. A high-potential power supply voltage ELVDD can be provided to the sub-pixel SP according to an embodiment from a power management circuit 700 through a first power supply line 32, a low-potential power supply voltage ELVSS can be provided to the sub-pixel SP according to an embodiment through a common electrode (cathode electrode) CE and a second power supply line 34, and a reference voltage Vref can be provided to the sub-pixel SP according to an embodiment through a reference line 24.

[0048] The gate driver 200 can be disposed in a border area BZ of the display panel 100, or can be disposed to be distributed in a display area DA. The gate driver 200 according to an embodiment can be embedded in a gate-in-panel (GIP) type, which is composed of transistors formed by the same process as the transistors in the display area (DA). The gate driver 200 according to an embodiment can be disposed in any one of a first border area BZ1 and a second border area BZ2 that face each other, with the display area DA therebetween, or can be disposed on both the first border area BZ1 and the second border area BZ2.

[0049] The gate driver 200 can include at least one scan driver 210 that drives at least one gate line 12 and at least one light emission control driver 220 that drives at least one gate line 16. The number of gate lines connected to the sub-pixel SP, the number of scan drivers 210, and the number of light emission control drivers 220 can vary according to the detailed configuration of the pixel circuit 10 included in the sub-pixel SP.

[0050] A plurality of gate control signals can be provided from a timing controller 400 to the gate driver 200 for operation. In one embodiment, a plurality of gate control signals can be provided from the timing controller 400 to the gate driver 200 through a level shifter.

[0051] The scan driver 210 may supply at least one scan signal SCAN to at least one gate line 12 disposed on each of a plurality of pixel row lines by using a plurality of first gate control signals.

[0052] The light emission control driver 220 may supply at least one light emission control signal EM to at least one gate line 16 disposed on each of a plurality of pixel row lines by using a plurality of second gate control signals.

[0053] A plurality of transistors disposed in the display area DA of the display panel 100 and the border area BZ including the gate driver 200 may include at least one of an LTPS transistor using a low temperature polycrystalline silicon (LTPS) semiconductor and an oxide transistor using a metal oxide semiconductor. The display panel 100 according to an embodiment may be configured to coexist with the LTPS transistor and the oxide transistor to reduce power consumption.

[0054] The data driver 300 may convert digital data provided from the timing controller 400 with a data control signal into an analog data signal to supply a data voltage Vdata to the data lines 22 of the display panel 100. The data driver 300 may include a gamma voltage generation unit, and may convert the digital data into an analog data voltage by using a gamma voltage provided from the gamma voltage generation unit.

[0055] The data driver 300 may include at least one data driving IC (integrated circuit) that drives a plurality of data lines 22 disposed on the display panel 100. Each data driving IC may be mounted on each circuit film and connected to the display panel 100. The circuit film on which the data driving IC is mounted may be electrically connected to the display panel 100 via an anisotropic conductive film (ACF) bonded to a pad area disposed in the border area BZ3 of the display panel 100. The circuit film may be any one of a chip on film (COF), a flexible printed circuit (FPC), and a flexible flat cable (FFC).

[0056] A timing control signal and image data may be provided from the host system 2000 to the timing controller 400.

[0057] The host system 2000 may be any one of a computer, a television system, a set-top box, a system on a mobile terminal such as a tablet or a cellular phone, or an automotive system.

[0058] The timing controller 400 may control operations of the gate driver 200 and the data driver 300 by using the timing control signal provided from the host system 2000 and timing setting information stored internally. The timing controller 400 may generate a gate control signal to control the operation of the gate driver 200, and may generate a data control signal to control the operation of the data driver 300.

[0059] The timing controller 400 can perform various image processing operations using the image data provided from the host system 2000, including image quality correction, afterimage compensation, brightness correction to reduce power consumption, etc., and can output the image data corrected through the image processing to the data driver 300.

[0060] The timing controller 400 according to an embodiment can be provided with sensing data as a result of sensing the electrical characteristics of the display panel 100 from the sensing circuit 600 in the sensing mode, and can predict (calculate) the change in the electrical characteristics caused by the deterioration of the light-emitting element EL based on the sensing data. When the light-emitting element EL deteriorates due to long-term driving, the current density may decrease, which may increase the impedance and the threshold voltage. The timing controller 400 can measure (predict) the impedance change corresponding to the deterioration amount of the light-emitting element EL by calculating the threshold voltage and / or the threshold voltage shift (shift value) of the light-emitting element EL based on the sensing data of the display panel 100 provided from the sensing circuit 600.

[0061] The timing controller 400 according to an embodiment can accumulate the image data, and determine the sensing area by predicting the deterioration area having a relatively large amount of deterioration in the display panel 100 based on the accumulated data, and can sense the electrical characteristics of the determined sensing area through the sensing circuit 600 to calculate the change in the electrical characteristics of the light-emitting element EL.

[0062] According to an embodiment, the timing controller 400 can calculate the sensing data for each sub-pixel by scaling the sensing data of the sensing area including a plurality of sub-pixels for each sub-pixel.

[0063] The timing controller 400 according to an embodiment can calculate the amount of change in the electrical characteristics of the light-emitting element EL, i.e., the threshold voltage shift, in the first sensing area (maximum deterioration area) based on the difference between the sensing data in the first sensing area (maximum deterioration area) and the sensing data in the second sensing area (minimum deterioration area).

[0064] The timing controller 400 according to an embodiment can determine whether there is an error in the sensing data, and can adjust the sensing current applied to the display panel 100 via the power management circuit 700 when determining an error in the sensing data. The timing controller 400 according to an embodiment can compare the current sensing data with the previous sensing data to determine whether there is an error in the current sensing data. The timing controller 400 according to an embodiment can control to repeat the sensing operation on the same sensing path of the display panel 100 using the adjusted sensing current, and can repeat the adjustment of the sensing current and the same sensing operation until the sensing data provided through the sensing circuit 600 falls within a preset target range. A specific description thereof will be described later.

[0065] According to one embodiment, the timing controller 400 may calculate a change (threshold voltage shift value) in the electrical characteristics of the sensed light-emitting element EL based on the sensed data included in the target range. According to one embodiment, the timing controller 400 may calculate a compensation gain (brightness gain) to compensate for the degradation of the light-emitting element EL based on the amount of change (threshold voltage shift value) in the electrical characteristics of the light-emitting element EL, and store it in the memory 500.

[0066] The timing controller 400 may compensate for and output the image data by using the compensation gain stored in the memory 500 to compensate for the afterimage caused by the degradation of each light-emitting element EL.

[0067] The sensing circuit 600 may sense the electrical characteristics of the sensing area of the display panel 100 as the voltage through the second power line 34 in the sensing mode according to the control of the timing controller 400, and may convert the sensed voltage into sensed data and transmit it to the timing controller 400.

[0068] According to one embodiment, the sensing circuit 600 may sense the electrical characteristics of the sensing area multiple times, determine the median (average value) of the generated multiple sensed data as the final sensed data, and transmit it to the timing controller 400.

[0069] According to one embodiment, the sensing circuit 600 may sense the electrical characteristics of each color of the sensing area of the display panel 100 as the voltage through the second power line 34 in the sensing mode.

[0070] According to one embodiment, the display device 1000 may apply the maximum (white) gray-scale data voltage to the sensing sub-pixels to cause the light-emitting element EL to emit light, and may apply the minimum (black) gray-scale data voltage to the non-sensing sub-pixels to cause the light-emitting element EL not to emit light.

[0071] Since the sensing circuit 600 according to one embodiment senses the electrical characteristics of the sensing sub-pixels by using the common cathode electrode CE and the second power line 34 shared by the sensing sub-pixels and the non-sensing sub-pixels in the display panel 100, the sensing accuracy of the sensing sub-pixels may be deteriorated or a sensing error may be caused due to the influence of the leakage current flowing through the non-sensing sub-pixels.

[0072] To solve this problem, the display device 1000 according to an embodiment can minimize the influence of leakage current by adjusting (changing) the sensing current applied to the display panel 100 in the sensing mode. Therefore, the display device 1000 according to an embodiment can improve the sensing accuracy of changes in the electrical characteristics of the sensing sub-pixels SP and the light-emitting elements EL by performing a sensing operation using a sensing current that minimizes the influence of leakage current, which can result in minimizing afterimage compensation distortion or improving afterimage compensation performance.

[0073] The sensing mode of the display device 1000 according to an embodiment can be executed under the instruction of the host system 2000, can be executed by a user request via the host system 2000, or can be executed according to an order determined by the timing controller 400.

[0074] The power management circuit (PMIC) 700 can generate and provide a plurality of power supply voltages required for the operation of the display driver circuit 900 using an input voltage. The power management circuit 700 can generate a high-potential power supply voltage ELVDD, a low-potential power supply voltage ELVSS, and a reference voltage Vref and supply them to the display panel 100.

[0075] Setting values of the high-potential power supply voltage ELVDD and the low-potential power supply voltage ELVSS that vary for each of the display mode and the sensing mode can be provided from the timing controller 400 to the power management circuit 700 according to an embodiment. The power management circuit 700 according to an embodiment can generate the high-potential power supply voltage ELVDD and / or the low-potential power supply voltage ELVSS that are set differently in the sensing mode than in the display mode and apply them to the display panel 100.

[0076] The power management circuit 700 according to an embodiment can receive a setting value of the sensing current from the timing controller 400 to generate and apply the sensing current to the display panel 100 in the sensing mode. Setting values of a varying sensing current can be provided from the timing controller 400 to the power management circuit 700 according to an embodiment to generate and apply the varying sensing current to the display panel 100 in the sensing mode.

[0077] Figure 3 is an equivalent circuit showing the sub-pixel configuration in a display panel according to an embodiment of the present disclosure, Figure 4 is a diagram showing the driving waveform of a sub-pixel according to an embodiment of the present disclosure.

[0078] Reference Figure 3, the sub-pixel SP may include a light-emitting element EL and a pixel circuit 10 for driving the light-emitting element EL. In one embodiment, the pixel circuit 10 may include a driving transistor DT, a plurality of switching transistors T1 to T5, and a storage capacitor Cst, but is not limited to this configuration.

[0079] The first scan signal SCAN1 may be provided to the pixel circuit 10 from the first scan driver 210 through the first gate line 12, and the second scan signal SCAN2 may be provided to the pixel circuit 10 from the second scan driver 212 through the second gate line 14.

[0080] The emission control signal EM may be provided to the pixel circuit 10 from the first emission control driver 220 through the third gate line 16.

[0081] The data voltage Vdata may be provided to the pixel circuit 10 through the data line 22 from the data driver 300 ( Figure 1 ). The high-potential power supply voltage ELVDD may be provided to the pixel circuit 10 from the power management circuit 700 ( Figure 1 ) through the first power supply line 32, the low-potential power supply voltage ELVSS may be provided to the pixel circuit 10 through the second power supply line 34 and the common electrode CE, and the reference voltage Vref may be provided to the pixel circuit 10 through the reference line 24.

[0082] Reference Figure 3 , the sub-pixel SP may be driven to include an initial period (t1), a sampling and writing period (t2), and an emission period (t3) per frame period (N).

[0083] Each of the driving transistor DT and the plurality of switching transistors T1 to T5 of the pixel circuit 10 includes a gate electrode, a source electrode, and a drain electrode. Since the source electrode and the drain electrode are not fixed and may change according to the direction of the voltage and current applied to the gate electrode, one of the source electrode and the drain electrode may be represented as the first electrode, and the other may be represented as the second electrode. The driving transistor DT and the plurality of switching transistors T1 to T5 of the pixel circuit 10 may be made of at least one of polysilicon semiconductors, amorphous silicon semiconductors, and oxide semiconductors, and may be P-type or N-type, or may be a mixture of P-type and N-type.

[0084] The light-emitting element EL may include an anode electrode AE connected to a fourth switching transistor T4, a cathode electrode CE connected to a second power supply line 34 that provides a low-potential power supply voltage ELVSS, and a light-emitting element layer between the anode electrode AE and the cathode electrode CE. When a driving current is supplied from a driving transistor DT to the light-emitting element EL through the fourth switching transistor T4, electrons from the cathode electrode CE are injected into the light-emitting element layer, and holes from the anode electrode AE are injected into the light-emitting element layer, and a fluorescent or phosphorescent material emits light through recombination of electrons and holes in the light-emitting element layer. Thus, the light-emitting element EL can emit light with a brightness proportional to the current value of the driving current.

[0085] The gate electrode of the driving transistor DT may be connected to a storage capacitor Cst, the first electrode may be connected to a first power supply line 32 that provides a high-potential power supply voltage ELVDD, and the second electrode may be connected to the first electrode of the fourth switching transistor T4. The driving transistor DT may be connected to the light-emitting element EL through the fourth switching transistor T4 and may drive the light-emitting element EL through the fourth switching transistor T4. The driving transistor DT may control the emission intensity of the light-emitting element EL through the fourth switching transistor T4 by controlling the driving current according to the driving voltage charged on the storage capacitor Cst.

[0086] The storage capacitor Cst may be connected between the second electrode of the first switching transistor T1 and the gate electrode of the driving transistor DT to charge a driving voltage corresponding to the data voltage Vdata. The storage capacitor Cst may hold the charged driving voltage during a light-emitting period t3 when the first switching transistor T1 is turned off and supply it to the driving transistor DT.

[0087] The first switching transistor T1 may be turned on or off in response to a first scan signal SCAN1 provided on a first gate line 12 provided on the i-th (i is a natural number) pixel row line. During a sampling and writing period t2 in which the first scan signal SCAN1 has a gate-on voltage VON, the first switching transistor T1 may supply the data voltage Vdata provided through a data line 22 to the first electrode of the storage capacitor CST. The switching transistor T1 may be turned off during an initial period t1 and a light-emitting period t3 in which the first scan signal SCAN1 has a gate-off voltage VOFF.

[0088] The second switching transistor T2 and the fifth switching transistor T5 can be turned on or off in response to a second scan signal SCAN2 of a second gate line 14 supplied to the i-th pixel row line. The second switching transistor T2 and the fifth switching transistor T5 can be turned on during an initial period t1 and a sampling and writing period t2 in which the second scan signal SCAN2 has a gate-on voltage VON, and can be turned off during a light-emitting period t3 in which the second scan signal SCAN2 has a gate-off voltage VOFF.

[0089] During the initial period t1 and the sampling and writing period t2, in response to the second scan signal SCAN2, the second switching transistor T2 can connect the driving transistor DT into a diode structure by connecting the gate electrode and the second electrode of the driving transistor DT. The second switching transistor T2 can compensate for the threshold voltage Vth of the driving transistor DT by charging the threshold voltage Vth of the driving transistor DT to the storage capacitor Cst. Therefore, the storage capacitor Cst can charge a data voltage that compensates for the threshold voltage Vth of the driving transistor DT.

[0090] The fifth switching transistor T5 can supply a reference voltage Vref supplied through a reference line 24 to an anode electrode AE of the light-emitting element EL during the initial period t1 and the sampling and writing period t2 in response to the second scan signal SCAN2.

[0091] The third switching transistor T3 and the fourth switching transistor T4 can be turned on or off in response to a light-emitting control signal EM of a third gate line 16 supplied to the i-th pixel row line. The third switching transistor T3 and the fourth switching transistor T4 can be turned on during an initial period t1 and a light-emitting period t3 in which the light-emitting control signal EM has a gate-on voltage VON, and can be turned off during a sampling and writing period t2 in which the light-emitting control signal EM has a gate-off voltage VOFF and a period between the sampling and writing period t2 and the light-emitting period t3.

[0092] The third switching transistor T3 can supply a reference voltage Vref supplied through a reference line 24 to a first electrode of the storage capacitor Cst during the initial period t1 and the light-emitting period t3 in response to the light-emitting control signal EM.

[0093] The fourth switching transistor T4 can connect the driving transistor DT to the light-emitting element EL during the initial period t1 and the light-emitting period t3 in response to the light-emitting control signal EM.

[0094] During the light-emitting period t3 of each frame N, the driving transistor DT can drive the light-emitting element EL through the fourth switching transistor T4.

[0095] Figure 5It is a diagram showing a sensing path of a sensing sub-pixel in a display device according to an embodiment of the present disclosure.

[0096] Reference Figure 5 , the power management circuit 700 may generate a high-potential power supply voltage EVDD, a low-potential power supply voltage ELVSS, and a reference voltage Vref for the sensing mode and apply them to the display panel 100, and may apply a sensing current Iforce as a constant current through the first power line 32.

[0097] The second power line 34 of the display panel 100 may be connected to the sensing circuit 600 through a second power supply line 36 passing through the circuit film COF. The second power supply line 36 may be connected to the power management circuit 700 to supply the low-potential power supply voltage ELVSS to the display panel 100.

[0098] The sensing circuit 600 according to an embodiment may sense a voltage Vsensing reflecting the electrical characteristics of the sensing sub-pixel SP by detecting the voltage at the end of the second power line 32 using the sensing current Iforce flowing through the sensing path of the sensing sub-pixel SP of the display panel 100, and may convert the sensed voltage Vsensing into sensing data SD and transmit it to the timing controller 400.

[0099] According to an embodiment, the sensing circuit 600 may include a voltage sensing circuit 610, a low-pass filter (LPF) 620, and an analog-to-digital converter (ADC) 630.

[0100] The voltage sensing circuit 610 may detect the voltage between the second power line 34 and the ground GND of the display panel 100 using the sensing current Iforce and output it as the sensing voltage Vsensing. In one embodiment, the voltage sensing circuit 610 may include a current regulator, a level rise / fall circuit, a switching element, etc.

[0101] The low-pass filter 620 may include a resistor R and a capacitor C to block high-frequency noise.

[0102] The ADC 630 may digitally convert the sensed voltage Vsensing into sensing data SD and output it to the timing controller 400.

[0103] Reference Figure 5 , the same driving waveform as the N frames shown in Figure 4 may be used to drive the sub-pixel SP whose electrical characteristics are sensed in the display panel 100.

[0104] Reference Figure 4 and Figure 5, during the sampling and writing period t2, a data voltage Vdata of white gray scale is provided to the sensing sub-pixel SP to charge the driving voltage to the storage capacitor Cst, and during the light emitting period t3, the driving transistor DT can cause the light emitting element EL to emit light through the fourth switching transistor T4.

[0105] During the light emitting period t3, a sensing current Iforce can flow through the sensing path (the sensing path is connected from the first power supply line 32, through the driving transistor DT, the fourth switching transistor T4, and the light emitting element EL of the sensing sub-pixel SP, to the second power supply line 34 in the display panel 100), and reaches the sensing circuit 600 through the second power supply line 36 including a circuit film COF, etc.

[0106] By sensing the voltage between the second power supply line 32 and the ground GND using the sensing current Iforce, the sensing circuit 600 can sense the electrical characteristics of the sensing sub-pixel SP reflecting the threshold voltage of the light emitting element EL as a sensing voltage Vsensing, and convert the sensing voltage into sensing data SD.

[0107] The sensing voltage Vsensing in the sensing circuit 600 can be a voltage reflecting components of the electrical characteristics included in the sensing path, such as the threshold voltage of the driving transistor DT, the threshold voltage of the fourth switching transistor T4, the threshold voltage of the light emitting element EL, and the voltage reduced by the wiring resistance RCOF of the circuit film (COF), etc. For example, the sensing voltage Vsensing can be a voltage reflected by adding or subtracting the voltage component of the sensing path from the first power supply voltage ELVDD.

[0108] According to an embodiment, the timing controller 400 ( Figure 1 ) can calculate the threshold voltage offset value based on the degradation of the light emitting element EL of the first sub-pixel SP by calculating the difference between the first sensing data of the first sub-pixel SP sensed in the maximum degradation region and the second sensing data of the second sub-pixel SP sensed in the minimum degradation region. Based on the threshold voltage offset value, the timing controller 400 according to an embodiment can calculate a compensation gain to compensate for the degradation of the light emitting element EL1 and store it in the memory 500.

[0109] According to an embodiment, the display device 1000 can improve the sensing accuracy of the electrical characteristic changes of the sensing sub-pixel SP and the light emitting element EL by adjusting (changing) the sensing current Iforce applied to the display panel 100 in the sensing mode, so as to perform the sensing operation using the sensing current Iforce that minimizes the leakage current effect, thereby minimizing the afterimage compensation distortion or improving the afterimage compensation performance.

[0110] Figure 6 It is a view of a sensing area of a display device according to an embodiment of the present disclosure.

[0111] Reference Figure 1 and Figure 6 Referring to FIGS. 6 and 7, a timing controller 400 of a display device 1000 according to an embodiment may use a cumulative result of image data to determine at least one sensing area SA predicted to be a maximum degradation area in a display panel 100. The at least one sensing area SA may include a plurality of sub-pixels having similar degradation amounts.

[0112] After the sensing area SA of the display panel 100 emits light using a data voltage having a white gray scale (maximum gray scale, maximum brightness) and the non-sensing area NSA may not emit light using a data voltage having a black gray scale (minimum gray scale, minimum brightness), a display device 1000 according to an embodiment may sense electrical characteristics of the sensing area SA in a sensing mode.

[0113] A display device 1000 according to an embodiment may divide the sensing area SA by colors of sub-pixels and sequentially sense the color-divided sensing area SA of the display panel 100.

[0114] Figures 7 to 9 It is a view showing a color-specific sensing path in a display device according to an embodiment of the present disclosure.

[0115] Reference Figures 7 to 9 Referring to FIG. 10, a display device according to an embodiment may sense a first color sub-pixel SP1 in a first sensing period, sense a second color sub-pixel SP2 in a second sensing period, and sense a third color sub-pixel SP3 in a third sensing period among the sensing areas SA of the display panel 100.

[0116] Reference Figure 7 Referring to FIG. 11, a display device according to an embodiment may cause a light-emitting element EL of a first sensing sub-pixel SP1 to emit light with a white gray scale (brightness) in the sensing area SA of the display panel 100, and cause non-sensing sub-pixels SP2 and SP3 in the sensing area SA and sub-pixels SP1, SP2, and SP3 in the non-sensing area not to emit light with a black gray scale (brightness). A sensing circuit 600 may sense electrical characteristics of the first sensing sub-pixel SP1 reflecting a threshold voltage of the light-emitting element EL of the first sensing sub-pixel SP1 by sensing a voltage at an end of a second power line 34 using a sensing current Iforce flowing from a first power line 32 through a first sensing path passing through the light-emitting element EL of the first sensing sub-pixel SP1 to the second power line 34.

[0117] Reference Figure 8, a display device according to an embodiment can cause the light-emitting element EL of the second sensing sub-pixel SP2 to emit light in white grayscale in the sensing region SA of the display panel 100, and cause the non-sensing sub-pixels SP1 and SP3 in the sensing region SA and the sub-pixels SP1, SP2, and SP3 in the non-sensing region not to emit light in black grayscale. The sensing circuit 600 can sense the voltage at the end of the second power line 34 by using the sensing current Iforce that flows from the first power line 32 through the second sensing path passing through the light-emitting element EL of the second sensing sub-pixel SP2 to the second power line 34, so as to sense the electrical characteristics of the second sensing sub-pixel SP2 that reflect the threshold voltage of the light-emitting element EL of the second sensing sub-pixel SP2.

[0118] Reference Figure 9 , a display device according to an embodiment can cause the light-emitting element ELS of the third sensing sub-pixel SP3 to emit light in white grayscale in the sensing region SA of the display panel 100, and cause the non-sensing sub-pixels SP1 and SP2 in the sensing region SA and the sub-pixels SP1, SP2, and SP3 in the non-sensing region not to emit light in black grayscale. The sensing circuit 600 can sense the voltage at the end of the second power line 34 by using the sensing current Iforce that flows from the first power line 32 through the third sensing path passing through the light-emitting element EL of the third sensing sub-pixel SP3 to the second power line 34, so as to sense the electrical characteristics of the third sensing sub-pixel SP3 that reflect the threshold voltage of the light-emitting element EL of the third sensing sub-pixel SP3.

[0119] Figure 10 is a diagram showing the flow of leakage current in the sensing operation of a display device according to an embodiment of the present disclosure, Figure 11 is a graph showing the current-voltage change characteristics of a light-emitting element due to the influence of leakage current in a display device according to an embodiment of the present disclosure.

[0120] Reference Figure 10, in one embodiment, when causing the sensing sub-pixel SP1 in the sensing area of the display panel 100 to emit light and sensing the electrical characteristics of the sensing sub-pixel SP1 in the sensing area of the display panel 100, leakage current may occur in the non-sensing sub-pixels SP2, SP3 in the sensing area SA displaying black and the non-sensing sub-pixels SP1, SP2, SP3 in the non-sensing area. In this case, the sensing current Iforce that should only flow through the sensing path of the sensing sub-pixel SP1 can be distributed to the non-sensing sub-pixels SP2, SP3 in the sensing area SA and the non-sensing sub-pixels SP1, SP2, SP3 in the non-sensing area, causing the low-potential power supply voltage ELVSS of the second power supply line 34 to increase. Therefore, sensing distortion may occur where the sensing data sensed by the sensing circuit 600 decreases from the sensing data sensed in the previous sensing mode. As the threshold voltage Vth increases when the light-emitting element EL deteriorates, it is normal for the current sensing data to increase compared to the previous sensing data, and the current sensing data that is smaller than the previous sensing data can be determined as distortion caused by the leakage current effect.

[0121] Reference Figure 11 , when the light-emitting element EL deteriorates, it moves (increases) from the threshold voltage Vth1 in the current (I-EL)-voltage (V-EL) characteristic 602 before the deterioration of the light-emitting element EL to the threshold voltage Vth2 in the current (I-EL)-voltage (V-EL) characteristic 605 after the deterioration of the light-emitting element EL. Therefore, the display device according to one embodiment can calculate (predict) the threshold voltage offset value Vth shift from the sensing data of the sensing circuit 600 through the sensing operation of the light-emitting element EL using the sensing current Iforce to compensate for afterimages. During the sensing operation, when leakage current occurs, errors may occur in the sensing data, and the threshold voltage Vth3 and the threshold voltage offset value Vth shift of the light-emitting element EL calculated therefrom may be distorted, resulting in afterimage compensation distortion.

[0122] To solve this problem, the display device according to one embodiment can perform the sensing operation using the sensing current Iforce, which minimizes the influence of leakage current by adjusting (changing) the sensing current Iforce applied to the display panel 100, thereby improving the sensing accuracy of the threshold voltage Vth and / or the threshold voltage offset value Vth shift of the light-emitting element EL, which can lead to minimizing afterimage compensation distortion or improving afterimage compensation performance.

[0123] Figure 12 is a flowchart showing a method of driving a sensing mode of a display device according to an embodiment of the present disclosure, Figure 13It is a graph showing the change in the current-voltage characteristics of a light-emitting element in response to a change in the sensed current according to an embodiment of the present disclosure.

[0124] Reference Figure 12 , a display device according to an embodiment may start a sensing mode and set an initial sensing current Iforce S132.

[0125] A display device according to an embodiment may perform sensing of the electrical characteristics of at least one sensing region displaying a specific image pattern on a display panel using the sensing current Iforce and generate a first sensing sequence S133 of sensing data. The sensing data may include the threshold voltage Vth of the light-emitting element EL of the sensed sub-pixel.

[0126] A display device according to an embodiment may compare the current sensing data (“current sensing data”) of the sensing region with the last sensing data (“last sensing data”) measured in the previous sensing mode to determine whether the current sensing data (“current sensing data”) is distorted due to the influence of leakage current S134. The “current sensing data” may be the median or average of the current sensing data of multiple sensing regions for the current (nth) sensing mode. The “last sensing data” may be the median or average of the previous sensing data of multiple sensing regions for the previous (last, n-1) sensing mode.

[0127] A display device according to an embodiment may determine that the current sensing data (“current sensing data”) is distorted due to the influence of leakage current S134, “Yes”, when the current sensing data (“current sensing data”) is less than the last sensing data (“last sensing data”), and may change (adjust) the sensing current Iforce S137. A display device according to an embodiment may increase the sensing current Iforce according to a preset set value. A display device according to an embodiment may search for the sensing current Iforce using a binary search method to determine the current value, and may increase the sensing current Iforce to the determined current value.

[0128] A display device according to an embodiment may apply the adjusted sensing current Iforce to the display panel and repeat the second sensing sequence of displaying a specific image pattern in the sensing region and sensing the sensing region, which is the same as the first sensing sequence, so that the current sensing data (“current sensing data”) can be compared with the last sensing data (“last sensing data”) S133, S134. In a display device according to an embodiment, as the current value of the sensing current Iforce increases, the brightness of the specific image pattern displayed in the sensing region may increase.

[0129] In a display device according to an embodiment, when the current sensed data (“present sensed data”) is less than the last sensed data (“last sensed data”) (S134, “Yes”), the variable (adjusted) sensing current Iforce of step S137 and the same sensing sequence steps S133, S134 may be repeated.

[0130] The display device according to an embodiment may repeat the variable (adjusted) sensing current Iforce step S137 and the same sensing sequence steps S133, S134 until the “present sensed data” enters a target range where the “present sensed data” is greater than the “last sensed data”.

[0131] When the current sensed data (“present sensed data”) enters a target range greater than the last sensed data (“last sensed data”) (S134, “No”), the display device according to an embodiment may determine the current sensed data as normal data, calculate a threshold voltage offset value of the light-emitting element EL based on the current sensed data, and calculate a compensation gain S135. The display device according to an embodiment may store the calculated compensation gain in a memory to update the compensation gain S136, and may terminate the sensing mode.

[0132] Reference Figure 13 , as the light-emitting element EL deteriorates, it moves from the threshold voltage Vth1 in the current (I-EL)-voltage (V-EL) characteristic 112 before the deterioration of the light-emitting element EL to the threshold voltage Vth2 in the current (I-EL)-voltage (V-EL) characteristic 114 after the deterioration of the light-emitting element EL, and moves to the threshold voltage Vth4 in the current (I-EL)-voltage (V-EL) characteristic 116 after the deterioration of the light-emitting element EL.

[0133] The display device according to an embodiment may sense the threshold voltage Vth2 of the light-emitting element EL through the last sensing mode operation (last sensing) using the sensing current Iforce, and calculate (predict) a threshold voltage offset value Vthshift-1 to compensate for an afterimage.

[0134] The display device according to an embodiment may sense the threshold voltage Vth3 or the threshold voltage offset value Vthshift-2 of the light-emitting element EL through the first sensing operation (“present first sensing”) of the current sensing mode using the sensing current Iforce. The display device according to an embodiment may adjust the sensing current Iforce when a sensing error occurs such that the current sensed data is less than the previous sensed data due to the influence of a leakage current, and sense the threshold voltage Vth4 of the light-emitting element EL through the second sensing operation (“present last sensing”) of the current sensing mode.

[0135] A display device according to an embodiment may determine that sensed data of a second sensing operation of a current sensing mode is greater than previous sensed data and is normal data included in a target range, and may calculate (predict) a threshold voltage shift value Vth shift-3 of a light emitting element (EL) from the current sensed data to compensate for an afterimage.

[0136] A display device according to an embodiment may use a binary search method to determine a current value of a sensing current Iforce.

[0137] The binary search method of the sensing current Iforce of a display device according to an embodiment may repeatedly perform the following operations: comparing a median value of current sensed data with a target value to reduce a range of a search current value by 1 / 2, repeating the operation until the number of current values in a search range is 1, and reducing the number of search current values by 1 / 2 in a single search.

[0138] In an embodiment, the display device may set a current value most similar to an average value of last sensed data of a previous sensing mode as a target value. A display device according to an embodiment may perform a sensing operation in each constant degradation period, and thus the meaning of constant degradation may mean that an average value of previous sensed data is the same as an average value of current sensed data. A display device according to an embodiment may find a condition (target value) where average values of sensed data are similar or equal, and then calculate a degradation characteristic of each sensing area of a display panel based on data sensed under the condition to compensate for an afterimage.

[0139] Figure 14 is a waveform diagram showing an exemplary sensing sequence of a display device according to an embodiment of the present disclosure.

[0140] Refer to Figure 1 and Figure 14 According to an embodiment, the display device 1000 may operate in a sensing mode in response to a sensing enable signal SEN_EN and a sensing start signal SEN_START transmitted from a host system 2000 at a first time T1, and a timing controller 400 may transmit a sensing status signal SEN_BUSY indicating an operation period SEP of the sensing mode to the host system 2000.

[0141] The display device 1000 according to an embodiment may divide the operation period SEP of the sensing mode into first to third sensing periods (R sensing, G sensing, B sensing) T3, T4, T5 divided by each of the R, G, and B colors. In each of the first to third sensing periods T3, T4, T5, the display device 1000 according to an embodiment may display a maximum gray-scale image pattern of each color in the sensing area of the display panel 100 to sense the sensing area SA, and may display black gray-scale in the non-sensing area.

[0142] In each of the first to third sensing periods (R sensing, G sensing, B sensing) T3, T4, T5 for each color, the display device 1000 according to an embodiment may repeat the sensing operation for at least one sensing area by changing the sensing current Iforce until the sensing data enters the target range, and the sensing circuit 600 may transmit a plurality of sensing data to the timing controller 400.

[0143] The display device 1000 according to an embodiment may display black gray-scale data on the display panel 100 in each of the second period T2 before the first sensing period T3 and the sixth period T6 after the third sensing period T5 of the operation period SEP of the sensing mode.

[0144] In the display device 1000 according to an embodiment, the timing controller 400 may provide the set values of the high-potential power supply voltages Sensing VDD, VSS for the sensing mode to the power management circuit 700 during the second period T2 when the display panel 100 displays black gray-scale. The power management circuit 700 may generate the high-potential power supply voltages ELVDD, ELVSS for the sensing mode during the sensing periods T3, T4, T5 and apply them to the display panel 100. The timing controller 400 may provide the set values of the high-potential power supply voltages NormalVDD, VSS for the display mode to the power management circuit 700 during the sixth period T6 when the display panel 100 displays black gray-scale. The power management circuit 700 may generate the high-potential power supply voltages ELVDD, ELVSS for the display mode during the display mode operation period T7 after the sensing period SEP and apply them to the display panel 100.

[0145] Figure 15 and Figure 16 are diagrams showing the brightness change process of an image pattern that can confirm a sensing behavior in response to a change in the sensing current of a display device according to an embodiment of the present disclosure.

[0146] Reference Figure 15, a display device according to an embodiment may perform an operation of sensing first sensing regions SA1 to SA5 for each region and each color using a first sensing current according to a first sensing sequence of a sensing mode.

[0147] A display device according to an embodiment may, in a first sensing period of a first sensing region SA1 of a display panel 100, display a maximum gradient image pattern on a red sub-pixel that is a sensing sub-pixel of the first sensing region SA1, display a minimum gradient image on sub-pixels of the first sensing region SA1 and a non-sensing region NSA, and sense electrical characteristics of the sensing (red) sub-pixels of the first sensing region SA1 using a first sensing current. Here, the first sensing region SA1 may display a red image pattern with a brightness of L11 of 1-1.

[0148] A display device according to an embodiment may, in a second sensing period of a first sensing region SA1 of a display panel 100, display a maximum gradient image pattern on a green sub-pixel that is a sensing sub-pixel of the first sensing region SA1, display a minimum gradient image on sub-pixels of the first sensing region SA1 and a non-sensing region NSA, and sense electrical characteristics of the sensing (green) sub-pixels of the first sensing region SA1 using a first sensing current. Here, the first sensing region SA1 may display a green image pattern with a brightness of L12 of 1-2.

[0149] A display device according to an embodiment may, in a second sensing period of a first sensing region SA1 of a display panel 100, display a maximum gradient image pattern on a blue sub-pixel that is a sensing sub-pixel of the first sensing region SA1, display a minimum gradient image on sub-pixels of the first sensing region SA1 and a non-sensing region NSA, and sense electrical characteristics of the sensing (blue) sub-pixels of the first sensing region SA1 using a first sensing current. Here, the first sensing region SA1 may display a blue image pattern with a brightness of L13 of 1-3.

[0150] A display device according to an embodiment may sequentially sense each of second sensing regions SA2 to SA5 of a display panel 100 for each color using the same first sensing current as that of the first sensing region SA1.

[0151] A display device according to an embodiment may sequentially display a red image pattern with a brightness of L11 of 1-1, a green image pattern with a brightness of L12 of 1-2, and a blue image pattern with a brightness of L13 of 1-3 in each of first sensing regions SA1 to SA5 sequentially sensed according to the first sensing sequence.

[0152] When the sensed data obtained through the first sensing sequence is determined to be a sensing error compared to the sensed data of the previous sensing pattern, a display device according to an embodiment may change the sensing current and repeat the sensing operation according to a second sensing sequence identical to the first sensing sequence, as Figure 16 shown.

[0153] Refer to Figure 16 , a display device according to an embodiment may sense the first sensing region SA1 to the fifth sensing region SA5 for each region and each color using a second sensing current that increases from the first sensing current according to the second sensing sequence of the sensing pattern.

[0154] A display device according to an embodiment may sequentially display a red image pattern with a brightness of L21 of 2-1, a green image pattern with a brightness of L22 of 2-2, and a blue image pattern with a brightness of L23 of 2-3 in each of the first sensing region SA1 to the fifth sensing region SA5 sensed sequentially according to the second sensing sequence.

[0155] A display device according to an embodiment may utilize a second sensing current in the second sensing sequence, the second sensing current increasing from the first sensing current utilized in the first sensing sequence. Accordingly, in the second sensing sequence, the brightness of each of the red image pattern with a brightness of L21 of 2-1, the green image pattern with a brightness of L22 of 2-2, and the blue image pattern with a brightness of L23 of 2-3 displayed for each color in the sensing regions SA1 to SA5 may increase more than the brightness of each of the red image pattern with a brightness of L11 of 1-1, the green image pattern with a brightness of L12 of 1-2, and the blue image pattern with a brightness of L13 of 1-3 displayed for each color in the sensing regions SA1 to SA5 in the first sensing sequence.

[0156] In this way, it is possible to verify whether the sensing operation is applied based on changing the sensing current of a display device according to an embodiment by confirming that the brightness of the image pattern displayed in at least one sensing region of the display panel gradually increases as the sensing current increases when repeating the same sensing sequence.

[0157] A display device according to some aspects may include: a display panel including a plurality of sub-pixels; a driver circuit configured to drive the display panel; and a sensing circuit that senses the electrical characteristics of a sensing region of the display panel to output sensed data, wherein the driver circuit may perform a sequence of changing the sensing current applied to a first power line until the sensed data falls within a target range in a sensing mode, and may repeat the sequence for the sensing region.

[0158] In a display device according to some aspects, the driver circuit may apply a first sensing current to the display panel in a first sensing sequence of a sensing mode, and may apply a second sensing current that increases more than the first sensing current to the display panel in a second sensing sequence of the sensing mode.

[0159] In a display device according to some aspects, the driver circuit may provide an image pattern of the same gray level to the sensing region in the first sensing sequence and the second sensing sequence, wherein the sensing region may display the image pattern at a first luminance in the first sensing sequence and may display the image pattern at a second luminance in the second sensing sequence.

[0160] In a display device according to some aspects, the driver circuit may sequentially display image patterns of each color in the sensing region in each of the first sensing sequence and the second sensing sequence, wherein the second luminance of the image pattern of each color displayed in the sensing region in the second sensing sequence may be brighter than the first luminance of the image pattern of each color displayed in the sensing region in the first sensing sequence.

[0161] In a display device according to some aspects, each of the first sensing sequence and the second sensing sequence may include a first color sensing period for sensing the electrical characteristics of the first color sub-pixels in the sensing region, a second color sensing period for sensing the electrical characteristics of the second color sub-pixels in the sensing region, and a third color sensing period for sensing the electrical characteristics of the third color sub-pixels in the sensing region.

[0162] In a display device according to some aspects, the sensing circuit may sense the electrical characteristics of the sensing region using a first sensing current flowing from a first power supply line through a sensing path in the sensing region and a second power supply line to output first sensing data in the first sensing sequence, and may sense the electrical characteristics of the sensing region using a second sensing current flowing from the first power supply line through the sensing path in the sensing region and the second power supply line to output second sensing data in the second sensing sequence.

[0163] In a display device according to some aspects, the driver circuit may perform a sequence of changing the sensing current by comparing the current sensing data in the current sensing mode with the previous sensing data in the previous sensing mode until the difference between the current sensing data and the previous sensing data falls within a target range, and may repeat the sequence.

[0164] In a display device according to some aspects, when comparing current sensing data in a current sensing mode with previous sensing data in a previous sensing mode and the difference between the current sensing data and the previous sensing data falls within the target range, the driver circuit may calculate a compensation gain for a change in an electrical characteristic of a sensing sub-pixel in the sensing region based on the current sensing data and store the compensation gain in a memory.

[0165] In a display device according to some aspects, the driver circuit may include a power management circuit that applies a first power voltage and a sensing current to a first power line shared with a plurality of sub-pixels of the display panel, and applies a second power voltage to a second power line shared with light emitting elements of the plurality of sub-pixels, wherein the power management circuit may apply a first power voltage for the sensing mode that is different from the first power voltage for the display mode, and may apply a second power voltage for the sensing mode that is different from the second power voltage for the display mode.

[0166] In a display device according to some aspects, the display panel may include a plurality of sensing regions, wherein the driver circuit may sense electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using a first sensing current in the first sensing sequence, and sense electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using the second sensing current in the second sensing sequence.

[0167] A driving method of a display device according to some aspects may include: sensing a sensing region of a display area using a first sensing current according to a first sensing sequence, determining whether the first sensing data is distorted by comparing the first sensing data sensed according to the first sensing sequence in the current sensing mode with the previous sensing data in the previous sensing mode, changing the first sensing current to a second sensing current when it is determined that the first sensing data is distorted, sensing the sensing region of the display area using the second sensing current according to the second sensing sequence, and repeating the step of determining whether the second sensing data is distorted by comparing the second sensing data sensed according to the second sensing sequence with the previous sensing data, and when the first sensing data or the second sensing data is determined to be normal, calculating a compensation gain for a change in an electrical characteristic of a sensing sub-pixel in the sensing region based on the sensed data determined to be normal and storing the compensation gain in a memory.

[0168] According to the driving method of a display device according to some aspects, the same grayscale image pattern may be displayed in the sensing region in the first sensing sequence and the second sensing sequence, the image pattern may be displayed in the sensing region with a first luminance according to the first sensing current in the first sensing sequence, and the image pattern may be displayed in the sensing region with a second luminance brighter than the first luminance according to the second sensing current higher than the first sensing current in the second sensing sequence.

[0169] According to the driving method of a display device according to some aspects, image patterns of each color may be sequentially displayed in the sensing region in each of the first sensing sequence and the second sensing sequence, wherein the second luminance of the image pattern of each color displayed in the sensing region in the second sensing sequence is brighter than the first luminance of the image pattern of each color displayed in the sensing region in the first sensing sequence.

[0170] According to the driving method of a display device according to some aspects, each of the first sensing sequence and the second sensing sequence may include a first color sensing period for sensing the electrical characteristics of the first color sub-pixels in the sensing region, a second color sensing period for sensing the electrical characteristics of the second color sub-pixels in the sensing region, and a third color sensing period for sensing the electrical characteristics of the third color sub-pixels in the sensing region.

[0171] According to the driving method of a display device according to some aspects, the electrical characteristics of the sensing region may be sensed using a first sensing current flowing from a first power line in the display panel through a sensing path in the sensing region and a second power line in the first sensing sequence, and the electrical characteristics of the sensing region may be sensed using a second sensing current flowing from the first power line through the sensing path in the sensing region and the second power line in the second sensing sequence.

[0172] According to the driving method of a display device according to some aspects, the second sensing current may be changed until the second sensing data of the current sensing mode is greater than the previous sensing data and falls within a target range, and the sensing sequence identical to the second sensing sequence may be repeated.

[0173] In the driving method of a display device according to some aspects, the display panel may include a plurality of sensing regions, the driving method may sense the electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using a first sensing current in the first sensing sequence, and may sense the electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using the second sensing current in the second sensing sequence.

[0174] As described above, a display device and a driving method thereof according to an embodiment can repeat a sensing operation by using a sensing current applied to a display panel that changes until the sensed data enters a target range, thereby improving the sensing accuracy of the electrical characteristics of a light-emitting element by using a sensing current that minimizes the influence of leakage current, thereby minimizing afterimage compensation distortion or improving afterimage compensation performance.

[0175] A display device and a driving method thereof according to an embodiment can improve the sensing accuracy of the electrical characteristics of a light-emitting element by using a sensing current that minimizes the influence of leakage current, thereby improving afterimage compensation performance. Therefore, the afterimage life of the light-emitting element can be increased and a low-power consumption effect can be achieved.

[0176] The above-described features, structures, and effects of the present disclosure are included in at least one embodiment of the present disclosure, but are not limited to only one embodiment. In addition, the features, structures, and effects described in at least one embodiment of the present disclosure can be implemented by those skilled in the art through combinations or modifications of other embodiments. Therefore, the content associated with the combinations and modifications should be construed as being within the scope of the present disclosure.

[0177] It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to cover modifications and variations of the present disclosure as long as they fall within the scope of the appended claims and their equivalents.

Claims

1. A display device, comprising: A display panel, the display panel comprising a plurality of sub-pixels, a driver circuit configured to drive the display panel, and a sensing circuit, wherein the sensing circuit senses electrical characteristics of a sensing area of ​​the display panel to output sensing data, The driver circuit performs a sequence in a sensing mode and repeats the sequence for the sensing region, the sequence varying a sensing current applied to the first power line until the sensing data falls within a target range.

2. The display device according to claim 1, in, The driver circuit applies a first sensing current to the display panel in a first sensing sequence of the sensing mode, and applies a second sensing current increased more than the first sensing current to the display panel in a second sensing sequence of the sensing mode.

3. The display device according to claim 2, in, the driver circuit provides the same grayscale image pattern to the sensing area in the first sensing sequence and the second sensing sequence, The sensing area displays the image pattern at a first brightness in the first sensing sequence, and displays the image pattern at a second brightness in the second sensing sequence.

4. The display device according to claim 3, in, the driver circuit sequentially displays the image pattern of each color in the sensing area in each of the first sensing sequence and the second sensing sequence, The second brightness of the image pattern of each color displayed in the sensing area in the second sensing sequence is brighter than the first brightness of the image pattern of each color displayed in the sensing area in the first sensing sequence.

5. The display device according to claim 4, in, Each of the first sensing sequence and the second sensing sequence comprises: a first color sensing period, in which an electrical characteristic of a first color sub-pixel in the sensing area is sensed; a second color sensing period in which an electrical characteristic of a second color sub-pixel in the sensing area is sensed, and A third color sensing period is used to sense the electrical characteristics of a third color sub-pixel in the sensing area.

6. The display device according to claim 1, wherein: The sensing circuit senses electrical characteristics of the sensing region using a first sensing current flowing from the first power line through a sensing path in the sensing region and a second power line in the first sensing sequence to output first sensing data, and senses electrical characteristics of the sensing region using a second sensing current flowing from the first power line through the sensing path in the sensing region and the second power line in the second sensing sequence to output second sensing data.

7. The display device according to claim 1, wherein: The driver circuit performs the sequence by comparing current sensing data in a current sensing mode with previous sensing data in a previous sensing mode, and repeats the sequence, wherein the sequence changes the sensing current until a difference between the current sensing data and the previous sensing data falls within the target range.

8. The display device according to claim 7, wherein: When current sensing data in a current sensing mode is compared with previous sensing data in a previous sensing mode and the difference between the current sensing data and the previous sensing data falls within the target range, the driver circuit calculates a compensation gain for changes in electrical characteristics of the sensing sub-pixels in the sensing area based on the current sensing data, and stores the compensation gain in a memory.

9. The display device according to claim 1, in, The driver circuit includes a power management circuit that applies a first power supply voltage and the sensing current to a first power supply line shared by a plurality of sub-pixels of the display panel, and applies a second power supply voltage to a second power supply line shared by light-emitting elements of the plurality of sub-pixels, The power management circuit applies a first power supply voltage for the sensing mode that is different from a first power supply voltage for the display mode, and applies a second power supply voltage for the sensing mode that is different from a second power supply voltage for the display mode.

10. The display device according to claim 2, in, The display panel includes a plurality of sensing areas. wherein the driver circuit senses electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using the first sensing current in the first sensing sequence, and senses electrical characteristics of the plurality of sensing regions for each of the sensing regions and for each color using the second sensing current in the second sensing sequence.

11. The display device according to claim 1, in, The target range is a range in which current sensing data of the sensing area of ​​the current sensing mode is greater than last sensing data measured in the previous sensing mode.

12. A method for driving a display device, comprising: sensing a sensing region of the display region using a first sensing current according to a first sensing sequence, determining whether the first sensing data is distorted by comparing first sensing data sensed according to the first sensing sequence of a current sensing mode with previous sensing data of a previous sensing mode, When it is determined that the first sensing data is distorted, the first sensing current is changed to a second sensing current, sensing the sensing area of ​​the display area using the second sensing current according to a second sensing sequence, and repeating the step of determining whether the second sensing data sensed according to the second sensing sequence is distorted by comparing the second sensing data with the previous sensing data, and When the first sensing data or the second sensing data is determined to be normal, a compensation gain for a change in electrical characteristics of the sensing subpixels in the sensing area is calculated based on the sensing data determined to be normal and the compensation gain is stored in a memory.

13. The method for driving a display device according to claim 12, in, displaying an image pattern of the same grayscale in the sensing area in the first sensing sequence and the second sensing sequence, wherein, in the first sensing sequence, the image pattern is displayed in the sensing area at a first brightness according to the first sensing current, and In the second sensing sequence, the image pattern is displayed in the sensing area at a second brightness brighter than the first brightness according to the second sensing current that is higher than the first sensing current.

14. The method for driving a display device according to claim 13, in, sequentially displaying the image pattern of each color in the sensing area in each of the first sensing sequence and the second sensing sequence, The second brightness of the image pattern of each color displayed in the sensing area in the second sensing sequence is brighter than the first brightness of the image pattern of each color displayed in the sensing area in the first sensing sequence.

15. The method for driving a display device according to claim 14, in, Each of the first sensing sequence and the second sensing sequence comprises: a first color sensing period, in which an electrical characteristic of a first color sub-pixel in the sensing area is sensed; a second color sensing period in which an electrical characteristic of a second color sub-pixel in the sensing area is sensed, and A third color sensing period is used to sense the electrical characteristics of a third color sub-pixel in the sensing area.

16. The method for driving a display device according to claim 12, in, sensing an electrical characteristic of the sensing region using the first sensing current flowing from the first power line in the display region through a sensing path and a second power line in the sensing region in the first sensing sequence, and In the second sensing sequence, the electrical characteristics of the sensing region are sensed using the second sensing current flowing from the first power line through the sensing path in the sensing region and the second power line.

17. The method for driving a display device according to claim 12, in, The second sensing current is changed until the second sensing data of the current sensing mode is greater than the previous sensing data and falls within a target range, and a sensing sequence identical to the second sensing sequence is repeated.

18. The method for driving a display device according to claim 17, in, The target range is a range in which current sensing data of the sensing area of ​​the current sensing mode is greater than last sensing data measured in the previous sensing mode.

19. The method for driving a display device according to claim 12, in, The display area includes a plurality of sensing areas. wherein the electrical characteristics of the plurality of sensing regions are sensed for each of the sensing regions and for each color using the first sensing current in the first sensing sequence, and The electrical characteristics of the plurality of sensing regions are sensed for each of the sensing regions and for each color using the second sensing current in the second sensing sequence.

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