KR102492972B1 - Controller, organic light emitting display device and the method for driving the organic light emitting display device - Google Patents

Abstract

According to the present embodiments, the black data voltage to be supplied to a specific subpixel is changed and supplied based on the temperature of the organic light emitting display device, thereby improving black expressiveness. A controller, an organic light emitting display device, and a driving method thereof capable of preventing a high-temperature black anomaly in which sub-pixels emit light unnecessarily by shifting to , thereby improving image quality.

Description

Controller, organic light emitting display device and its driving method

The present embodiments relate to a controller, an organic light emitting display device, and a driving method thereof.

Recently, an organic light emitting display device that has been in the limelight as a display device uses an organic light emitting diode (OLED) that emits light by itself, and has advantages such as fast response speed, luminous efficiency, luminance, and viewing angle.

In such an organic light emitting display device, subpixels including organic light emitting diodes are arranged in a matrix form, and brightness of subpixels selected by a scan signal is controlled according to gray levels of data.

Each sub-pixel of the organic light emitting display device includes an organic light emitting diode, a driving transistor for driving the diode, a scan transistor for transmitting a data voltage to the gate node of the driving transistor, and a storage capacitor for maintaining the voltage for a certain period of time. It is composed of, etc.

On the other hand, the conventional organic light emitting display device has a problem in that the expressiveness is lowered in the low gradation area due to various factors, and as a result, an image abnormality phenomenon occurs in which an image difference with other areas occurs.

In particular, the conventional organic light emitting display device has a problem in that the black expressive power is very low because the characteristic values of the transistors on the organic light emitting display panel change according to the temperature change.

An object of the present embodiments is to provide a controller, an organic light emitting display device, and a driving method capable of improving low grayscale expression in a low grayscale region.

Another object of the present embodiments is a controller, an organic light emitting display device, and a method for driving the same, which can prevent low gradation expressive power (in particular, black expressive power) from deteriorating due to a change in transistor characteristic values of an organic light emitting display panel according to temperature change. is to provide

Another object of the present embodiments is to provide a controller, an organic light emitting display device, and a driving method capable of improving black expressive power by changing a black data voltage according to a temperature change.

Another object of the present embodiments is to provide a controller and organic light emitting display that can improve image quality by preventing a high-temperature black anomaly, in which the threshold voltage of a driving transistor shifts in a negative direction as the temperature rises and unnecessarily emits light from subpixels. It is to provide a device and its driving method.

In one aspect, the present embodiments include an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, a data driver outputting data voltages to the plurality of data lines, and data An organic light emitting display device including a controller for controlling a driver may be provided.

In such an organic light emitting display device, a black data voltage supplied to a plurality of specific subpixels among a plurality of subpixels may be changed according to temperature.

In another aspect, the present embodiments include a temperature sensing step of sensing the temperature of the organic light emitting display device, and a black data voltage changing step of changing and supplying a black data voltage to be supplied to a specific subpixel based on the sensed temperature. A driving method of an organic light emitting display device may be provided.

The driving method may further include a black data voltage correction step of changing the black data voltage to be supplied to the specific subpixel when the specific subpixel emits light after the black data voltage changing step.

In another aspect, the present embodiments include an organic light emitting unit including a temperature checking unit that receives information about a detected temperature and a black data controller that changes and outputs black data to be supplied to a specific subpixel based on the detected temperature. A controller of the display device may be provided.

The aforementioned black data controller may receive a detection signal and correct black data to be supplied to a specific subpixel.

In another aspect, the present embodiments include an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, a data driver outputting data voltages to the plurality of data lines, An organic light emitting display device including a controller controlling a data driver may be provided.

In such an organic light emitting display device, a data voltage of a specific gray level supplied to all or part of a plurality of subpixels may be changed according to a temperature change.

A data voltage of a specific gray level may be changed in inverse proportion to temperature.

Also, the data voltage of a specific grayscale may be a black data voltage corresponding to a black grayscale.

In another aspect, the present embodiments include supplying an initial black data voltage to a specific subpixel, detecting whether the specific subpixel to which the initial black data voltage is supplied emits light, and detecting that the specific subpixel emits light. Then, a method of driving an organic light emitting display device including changing an initial black data voltage and supplying it to a specific subpixel can be provided.

According to the present embodiments as described above, it is possible to provide a controller, an organic light emitting display device, and a driving method capable of improving low grayscale expression in a low grayscale region.

In addition, according to the present embodiments, a controller, an organic light emitting display device, and driving thereof capable of preventing low gradation expressiveness (in particular, black expressive power) from deteriorating due to a change in transistor characteristic values of an organic light emitting display panel according to a temperature change. method can be provided.

In addition, according to the present embodiments, a controller capable of improving black expressiveness by changing a black data voltage according to a change in temperature, an organic light emitting display device, and a driving method thereof can be provided.

In addition, according to the present embodiments, the threshold voltage of the driving transistor shifts in a negative direction as the temperature rises, thereby preventing a high-temperature black anomaly in which sub-pixels unnecessarily emit light, thereby improving image quality, and an organic light emitting display. A device and its driving method can be provided.

1 is a system configuration diagram of an organic light emitting display device according to the present embodiments.
2 is an exemplary diagram of a sub-pixel structure of an organic light emitting display device according to the present embodiments.
3 is another exemplary diagram of a sub-pixel structure of an organic light emitting display device according to the present embodiments.
4 is a graph for explaining a dithering black data voltage used during dithering for low grayscale expression in an organic light emitting display device according to the present embodiments.
5 is a graph illustrating an upward process of a dithering black data voltage used in dithering for low grayscale expression in an organic light emitting display device according to the present exemplary embodiments.
6 is a diagram illustrating unit regions of an organic light emitting display panel when dithering black processing is varied for each unit region in the organic light emitting display device according to the present embodiments.
7A is a diagram illustrating a unit area not subjected to dithering black processing and a pure black data voltage used in the unit area in the organic light emitting display device according to the present exemplary embodiments.
7B is a diagram illustrating a dithering black processing area and a dithering black data voltage used in the dithering black processing area in the organic light emitting display device according to the present embodiments.
8 illustrates an unnecessary turn-on phenomenon of a driving transistor that occurs at a high temperature when a dithering black data voltage higher than a pure black data voltage is used during dithering black processing in an organic light emitting display device according to the present embodiments. it is a drawing
FIG. 9 is an organic light emitting display device according to the present embodiments, when a high dithering black data voltage is used during dithering black processing, a corresponding subpixel is unnecessary due to an unnecessary turn-on phenomenon of a driving transistor that occurs at a high temperature. It is a Vgs-Ids graph to explain the light emission phenomenon.
10 is an organic light emitting display device according to the present embodiments, when a high dithering black data voltage is used during dithering black processing, an unnecessary turn-on phenomenon of a driving transistor and an unnecessary light emission phenomenon of a subpixel under a high temperature situation It is a diagram schematically showing the resulting abnormal image.
11 is a diagram illustrating a system for changing a dithering black data voltage according to temperature in an organic light emitting display device according to example embodiments.
12 is a graph illustrating a black data voltage versus temperature when the dithering black data voltage is changed according to temperature in the organic light emitting display device according to the present embodiments.
FIG. 13 is a Vgs-Ids graph showing that an unnecessary light emission phenomenon is prevented according to a process of changing a dithering black data voltage according to temperature in an organic light emitting display device according to example embodiments.
14 is a diagram for explaining a method of utilizing memory information when changing a dithering black data voltage according to a detected temperature in an organic light emitting display device according to the present embodiments.
15 illustrates a method of correcting a dithering black data voltage that is changed by using memory information according to a detected temperature in an organic light emitting display device according to the present embodiments when it is not accurate, and a sensing circuit for the method. is a drawing showing
16 is a diagram illustrating a current sensor used when a dithering black data voltage is corrected in an organic light emitting display device according to example embodiments.
17A and 17B are diagrams illustrating installation of a current sensor used when a dithering black data voltage is corrected in an organic light emitting display device according to the present embodiments.
18 is a flowchart of a method of driving an organic light emitting display device according to example embodiments.
19 is a block diagram of a controller of an organic light emitting display device according to the present embodiments.
20 is another flowchart of a method of driving an organic light emitting display device according to the present embodiments.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention are described in detail below with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present invention. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element is or may be directly connected to that other element, but intervenes between each element. It will be understood that may be "interposed", or each component may be "connected", "coupled" or "connected" through other components.

1 is a system configuration diagram of an organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 1 , an organic light emitting display device 100 according to the present embodiments includes a plurality of data lines DL and a plurality of gate lines GL, and a plurality of data lines DL and a plurality of gate lines GL. An organic light emitting display panel 110 in which a plurality of sub pixels (SP) defined by the gate line GL are arranged, a data driver 120 driving a plurality of data lines DL, and a plurality of A gate driver 130 driving the gate line GL, a data driver 120 and a controller 140 controlling the gate driver 130, and the like are included.

The controller 140 controls the data driver 120 and the gate driver 130 by supplying various control signals to the data driver 120 and the gate driver 130 .

The controller 140 starts scanning according to the timing implemented in each frame, converts input image data input from the outside to suit the data signal format used by the data driver 120, and outputs the converted image data. , data drive is controlled at an appropriate time according to the scan.

The controller 140 may be a timing controller used in a typical display technology or a control device that further performs other control functions including a timing controller.

The controller 140 may be implemented as a separate component from the data driver 120 or may be implemented as an integrated circuit together with the data driver 120 .

The data driver 120 drives the plurality of data lines DL by supplying data voltages to the plurality of data lines DL. Here, the data driver 120 is also referred to as a 'source driver'.

The data driver 120 may include at least one source driver integrated circuit (SDIC) to drive a plurality of data lines.

Each source driver integrated circuit (SDIC) may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, and the like.

In some cases, each source driver integrated circuit (SDIC) may further include an analog to digital converter (ADC).

The gate driver 130 sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL. Here, the gate driver 130 is also referred to as a 'scan driver'.

The gate driver 130 may include at least one gate driver integrated circuit (GDIC).

Each gate driver integrated circuit (GDIC) may include a shift register, a level shifter, and the like.

The gate driver 130 sequentially supplies scan signals of an on voltage or an off voltage to the plurality of gate lines GL under the control of the controller 140 .

When a specific gate line is opened by the gate driver 130, the data driver 120 converts the image data received from the controller 140 into analog data voltages and supplies them to a plurality of data lines DL.

As shown in FIG. 1 , the data driver 120 may be located only on one side (eg, upper or lower side) of the organic light emitting display panel 110, and in some cases, the organic light emitting display panel 110 may be positioned according to a driving method or a panel design method. Both sides (eg, upper and lower sides) of the display panel 110 may be located.

As shown in FIG. 1 , the gate driver 130 may be located on only one side (eg, the left or right side) of the organic light emitting display panel 110, and in some cases, the organic light emitting display panel 110 may be positioned on the organic light emitting display panel 110 depending on the driving method or panel design method. Both sides (eg, left and right) of the light emitting display panel 110 may be located.

The above-described controller 140 includes various types of input image data, including a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable (DE) signal, a clock signal (CLK), and the like. Receive timing signals from outside (e.g. host system).

The controller 140 receives timing signals such as a vertical sync signal (Vsync), a horizontal sync signal (Hsync), an input DE signal, and a clock signal in order to control the data driver 120 and the gate driver 130, Various control signals are generated and output to the data driver 120 and the gate driver 130.

For example, in order to control the gate driver 130, the controller 140 includes a gate start pulse (GSP), a gate shift clock (GSC), and a gate output enable signal (GOE: It outputs various gate control signals (GCS: Gate Control Signal) including Gate Output Enable) and the like.

Here, the gate start pulse GSP controls the operation start timing of one or more gate driver integrated circuits constituting the gate driver 130 . The gate shift clock (GSC) is a clock signal commonly input to one or more gate driver integrated circuits and controls shift timing of scan signals (gate pulses). The gate output enable signal GOE specifies timing information of one or more gate driver integrated circuits.

In addition, the controller 140, in order to control the data driver 120, a source start pulse (SSP: Source Start Pulse), a source sampling clock (SSC: Source Sampling Clock), a source output enable signal (SOE: Source Output It outputs various data control signals (DCS) including Enable) and the like.

Here, the source start pulse SSP controls data sampling start timing of one or more source driver integrated circuits constituting the data driver 120 . The source sampling clock (SSC) is a clock signal that controls sampling timing of data in each source driver integrated circuit. The source output enable signal SOE controls output timing of the data driver 120 .

Meanwhile, each source driver integrated circuit (SDIC) included in the data driver 120 is connected to an organic light emitting display panel (TAB: Tape Automated Bonding) method or COG (Chip On Glass) method. 110), may be directly disposed on the organic light emitting display panel 110, or may be integrated and disposed on the organic light emitting display panel 110 according to circumstances.

In addition, each source driver integrated circuit SDIC may be implemented in a chip on film (COF) method mounted on a film SF connected to the organic light emitting display panel 110 .

Each gate driver integrated circuit (GDIC) included in the gate driver 130 is bonded to a bonding pad of the organic light emitting display panel 110 using a tape automated bonding (TAB) method or a chip on glass (COG) method. It may be connected or implemented in a GIP (Gate In Panel) type and directly disposed on the organic light emitting display panel 110, or may be integrated and disposed on the organic light emitting display panel 110 in some cases.

In addition, each gate driver integrated circuit (GDIC) may be implemented in a chip on film (COF) method mounted on a film GF connected to the organic light emitting display panel 110 .

The organic light emitting display device 100 according to the present embodiments includes at least one source printed circuit board (SPCB) and control components required for circuit connection to at least one source driver integrated circuit (SDIC). and a control printed circuit board (CPCB) for mounting various electrical devices.

At least one source driver integrated circuit (SDIC) may be directly mounted on the at least one source printed circuit board (SPCB), or a film SF having at least one source driver integrated circuit (SDIC) mounted may be connected.

In the control printed circuit board (CPCB), the controller 140 for controlling operations of the data driver 120 and the gate driver 130, the organic light emitting display panel 110, the data driver 120, and the gate driver 130 ), etc., a power controller that supplies various voltages or currents or controls various voltages or currents to be supplied may be mounted.

The at least one source printed circuit board (SPCB) and the control printed circuit board (CPCB) may be circuitically connected through at least one connecting member.

Here, the connecting member may be a flexible printed circuit (FPC) or a flexible flat cable (FFC).

At least one source printed circuit board (SPCB) and one control printed circuit board (CPCB) may be integrated into one printed circuit board.

Also, the controller 140 may be implemented by being integrated with a source driver integrated circuit (SDIC).

Each sub-pixel (SP) arranged on the organic light emitting display panel 110 includes an organic light emitting diode (OLED), which is a self-emitting element, and a driving transistor for driving the organic light emitting diode (OLED). It is composed of circuit elements such as

The type and number of circuit elements constituting each sub-pixel SP may be variously determined according to a provided function and a design method.

2 is an exemplary diagram of a sub-pixel structure of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 2 , in the organic light emitting display device 100 according to the present exemplary embodiments, each subpixel SP basically has an organic light emitting diode (OLED) and a drive that drives the organic light emitting diode (OLED). A driving transistor (DRT), a first transistor T1 for transferring a data voltage to a first node N1 corresponding to the gate node of the driving transistor DRT, and a data voltage corresponding to the image signal voltage or It may be configured to include a storage capacitor (Cst: Storage Capacitor) that maintains a voltage corresponding to this for one frame time.

An organic light emitting diode (OLED) may include a first electrode (eg, an anode electrode or a cathode electrode), an organic layer, and a second electrode (eg, a cathode electrode or an anode electrode).

The ground voltage EVSS may be applied to the second electrode of the organic light emitting diode OLED.

The driving transistor DRT drives the organic light emitting diode (OLED) by supplying a driving current to the organic light emitting diode (OLED).

The driving transistor DRT has a first node N1 , a second node N2 , and a third node N3 .

The first node N1 of the driving transistor DRT is a node corresponding to a gate node and may be electrically connected to a source node or a drain node of the first transistor T1.

The second node N2 of the driving transistor DRT may be electrically connected to the first electrode (eg, an anode electrode or a cathode electrode) of the organic light emitting diode OLED, and may be a source node or a drain node.

The third node N3 of the driving transistor DRT is a node to which the driving voltage EVDD is applied, and may be electrically connected to a driving voltage line (DVL) that supplies the driving voltage EVDD, and may be electrically connected to a drain. It can be a node or a source node.

The first transistor T1 is electrically connected between the data line DL and the first node N1 of the driving transistor DRT, and can be controlled by receiving the scan signal SCAN to the gate node through the gate line. there is.

The first transistor T1 may be turned on by the scan signal SCAN and transfer the data voltage Vdata supplied from the data line DL to the first node N1 of the driving transistor DRT. .

The storage capacitor Cst may be electrically connected between the first node N1 and the second node N2 of the driving transistor DRT.

The storage capacitor Cst is not a parasitic capacitor (eg, Cgs or Cgd) that is an internal capacitor existing between the first node N1 and the second node N2 of the driving transistor DRT, but It is an external capacitor intentionally designed outside the driving transistor (DRT).

Circuit elements such as organic light emitting diodes (OLEDs) and driving transistors (DRTs) may have unique characteristic values.

Here, a unique characteristic value of the organic light emitting diode (OLED) may be a threshold voltage, and a characteristic value of the driving transistor DRT may include a threshold voltage, mobility, and the like.

These circuit elements may change characteristic values depending on temperature, voltage application, and the like.

3 is another exemplary view of a sub-pixel structure of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 3 , each subpixel disposed on the organic light emitting display panel 110 according to the present embodiments includes, for example, an organic light emitting diode (OLED), a driving transistor (DRT), a first transistor (T1), and In addition to the storage capacitor Cst, a second transistor T2 may be further included.

Referring to FIG. 3 , the second transistor T2 is electrically connected between the second node N2 of the driving transistor DRT and a reference voltage line (RVL) supplying a reference voltage (Vref). , and can be controlled by receiving a sensing signal SENSE, which is a kind of scan signal, through a gate node.

By further including the aforementioned second transistor T2, the voltage state of the second node N2 of the driving transistor DRT in the subpixel SP can be effectively controlled.

The second transistor T2 is turned on by the sensing signal SENSE and applies the reference voltage Vref supplied through the reference voltage line RVL to the second node N2 of the driving transistor DRT. .

Meanwhile, the scan signal SCAN and the sensing signal SENSE may be separate gate signals. In this case, the scan signal SCAN and the sensing signal SENSE may be respectively applied to the gate node of the first transistor T1 and the gate node of the second transistor T2 through different gate lines.

In some cases, the scan signal SCAN and the sensing signal SENSE may be the same gate signal. In this case, the scan signal SCAN and the sensing signal SENSE may be commonly applied to the gate node of the first transistor T1 and the gate node of the second transistor T2 through the same gate line.

The driving transistor DRT, the first transistor T1 and the second transistor T2 may be implemented as n-type or p-type.

Hereinafter, a driving method for improving low grayscale expressive power of the organic light emitting display device 100 which may have the above-described subpixel structure will be described.

FIG. 4 is a graph for explaining a dithering black data voltage used during dithering for low grayscale expression in the organic light emitting display device 100 according to the present exemplary embodiments.

Referring to FIG. 4 , the organic light emitting display device 100 according to the present exemplary embodiments dithers a data voltage of 0 gray level and a data voltage of 1 gray level to express a low gray level, thereby dithering black data. voltage can be used.

In the organic light emitting display device 100 according to the present embodiments, the difference between the data voltage of gray level 0 and the data voltage of gray level 1 is relatively high in the process of switching between gray level 0 and gray level 1 to create a dithering black data voltage. can be big

Such a voltage difference may be caused by, for example, a conversion error between a digital voltage value and an analog voltage value.

Alternatively, the voltage difference may occur due to a limitation in the number of bits capable of processing data by the controller 140 or the source driver integrated circuit (SDIC).

As such, when a difference between a data voltage of 0 grayscale and a data voltage of 1 grayscale is large, an abnormal line may appear in a certain direction (eg, a vertical direction).

This phenomenon is referred to as "vertical line noise phenomenon" when abnormal lines occur in the vertical direction.

FIG. 5 is a graph for explaining an upward process of a dithering black data voltage Vdb used during dithering for low grayscale expression in the organic light emitting display device 100 according to the present exemplary embodiments.

As shown in FIG. 5 , the organic light emitting display device 100 according to the present exemplary embodiments can prevent vertical line noise by reducing a difference between a data voltage of 0 gray level and a data voltage of 1 gray level.

As shown in FIG. 5 , the organic light emitting display device 100 according to the present embodiments increases the pure black data voltage Vob to the dithering black data voltage Vdb, thereby increasing the 0 grayscale data voltage. It is possible to reduce the difference between the data voltage of 1 and the data voltage of 1 grayscale.

The pure black data voltage Vob and the dithering black data voltage Vdb are data voltages applied to the gate node N1 of the driving transistor DRT.

The pure black data voltage Vob may be a black data voltage used when dithering is not performed, and may be 0 [V] or a voltage almost similar to 0 [V].

Also, the dithering black data voltage Vdb is a black data voltage used in the case of dithering, and is higher than the pure black data voltage Vob.

By increasing the dithering black data voltage Vdb, a difference between a data voltage of 0 gray level and a data voltage of 1 gray level can be reduced.

The upper limit to which the dithering black data voltage Vdb can be increased may be the data voltage applied to the gate node N1 of the driving transistor DRT immediately before the driving transistor DRT changes from an off state to an on state. there is.

FIG. 6 is a diagram showing unit areas of the organic light emitting display panel 110 when dithering black processing is varied for each unit area in the organic light emitting display device 100 according to the present embodiments. FIG. In the organic light emitting display device 100 according to the present embodiments, it is a diagram showing a unit area not subjected to dithering black processing and a pure black data voltage Vob used in the unit area. FIG. In the organic light emitting display device 100 according to , this is a diagram showing a dithering black processing area (dithering black processing area) and a dithering black data voltage Vdb used in the unit area.

Referring to FIG. 6 , the entire area in which a plurality of subpixels are arranged in the organic light emitting display panel 110 may be divided into two or more unit areas treated with dithering black and managed.

In this specification, the dithering black processing refers to a process of expressing black in a subpixel using a dithering black data voltage Vdb corresponding to a higher voltage than the pure black data voltage Vob.

Each unit area may be composed of subpixels of M rows and N columns.

Here, one of M and N is a natural number greater than or equal to 1 and the other is a natural number greater than or equal to 2.

Dithering black processing may be performed for each unit area.

When the first unit area is determined to be a unit area not subjected to dithering black processing, subpixels included in the first unit area may receive the pure black data voltage Vob.

When the second unit area is determined to be a unit area to be subjected to dithering black processing, subpixels included in the second unit area may receive the dithering black data voltage Vdb.

Referring to FIGS. 6, 7A, and 7B , the controller 140 performs dithering black processing among a plurality of subpixels based on input image data for each of a plurality of subpixels input from a host system (not shown). It is possible to determine a plurality of specific sub-pixels to be.

As described above, the controller 140 determines specific subpixels to be subjected to dithering black processing based on the input image data for each subpixel, and does not perform dithering black processing on all subpixels. By performing the dithering black processing only, the processing load required for the dithering black processing can be reduced, and through this, an image display can be efficiently provided.

As shown in FIG. 6 , the entire area of the organic light emitting display panel 110 may be divided into two or more unit areas.

Each unit area may be composed of subpixels of M rows and N columns. Here, one of M and N is a natural number greater than or equal to 1 and the other is a natural number greater than or equal to 2.

The controller 140 may analyze the input image data for each subpixel and determine whether to perform dithering black processing for each unit area composed of subpixels in M row and N column.

The controller 1400 selects, for each unit area, subpixels to be expressed as 0 (Zero) grayscale among the subpixels in rows M and columns N based on the input image data of each of the subpixels in rows M and columns N included in the corresponding unit area. If the number is greater than or equal to a predetermined value, the corresponding unit area may be determined as a dithering black processing area to be subjected to dithering black processing.

Accordingly, the controller 1400 may determine the subpixels of row M and column N included in the dithering black processing area as the plurality of specific subpixels mentioned above.

As described above, the dithering black processing can be efficiently performed by performing the dithering black processing for each unit area larger than the area of one subpixel.

FIG. 7A exemplarily illustrates a unit area not subjected to dithering black processing, and FIG. 7B exemplarily illustrates a unit area subjected to dithering black processing.

In the examples of FIGS. 7A and 7B , one unit area is composed of subpixels of 8 rows and 4 columns. That is, as M = 8 and N = 4, this is a case where one unit area is composed of 32 subpixels.

For example, as a method of determining whether or not dithering black processing is performed for each unit area, 0 (Zero) is selected from among subpixels in 8 rows and 4 columns based on input image data of each of the subpixels in 8 rows and 4 columns included in the corresponding unit area. If the number of subpixels to be expressed as grayscale is greater than or equal to a predetermined value (eg, three), the corresponding unit area may be determined as a dithering black processing area.

In the case of the example of FIG. 7A , as a result of checking the input image data of each of the 32 subpixels, the controller 140 has 0 subpixels to be expressed in 0 (Zero) grayscale, so the corresponding unit area is dithering black. It is determined as a unit area that is not processed.

Accordingly, a pure black data voltage (Vob) may be supplied to 32 subpixels included in the unit area that are not subjected to dithering black processing in order to express 0 grayscale.

In the case of the example of FIG. 7B , as a result of checking the input image data of each of the 32 subpixels, the controller 140 has three subpixels to be expressed in 0 (Zero) grayscale, so the corresponding unit area is dithering black. It is determined as a unit area (dithering black processing area) to be processed.

Accordingly, the dithering black data voltage Vdb may be supplied to the 32 subpixels included in the unit area to which the dithering black processing is performed, in order to express 0 grayscale.

The dithering black data voltage Vdb may be higher than the pure black data voltage Vob.

The dithering black data voltage Vbd may be a fixed voltage value.

As such, when a dithering black data voltage Vbd higher than the pure black data voltage Vob is used to improve the vertical line noise phenomenon, a new problem may be caused.

This new problem may occur when the dithering black data voltage Vdb is a fixed voltage.

In the following, a new problem occurring when a dithering black data voltage Vdb corresponding to a fixed voltage higher than the pure black data voltage Vob is used will be described.

FIG. 8 illustrates driving that occurs in a high-temperature situation when a dithering black data voltage Vdb higher than the pure black data voltage Vob is used in the dithering black processing in the organic light emitting display device 100 according to the present embodiments. This diagram shows an unnecessary turn-on phenomenon of the transistor DRT.

9 is an unnecessary turn of the driving transistor DRT that occurs in a high temperature situation when a high dither black data voltage Vdb is used during dither black processing in the organic light emitting display device 100 according to the present embodiments. This is a Vgs-Ids graph for explaining a light emission phenomenon in which a corresponding subpixel is unnecessary due to an ON phenomenon.

FIG. 10 illustrates an unnecessary turn-on phenomenon of a driving transistor and sub-pixels at a high temperature when a high dither black data voltage Vdb is used during dither black processing in the organic light emitting display device 100 according to the present embodiments. It is a diagram schematically showing an abnormal image caused by an unnecessary light emission phenomenon.

However, below, it is assumed that the second node N2 of the driving transistor DRT is a source node and the third node N3 is a drain node.

Referring to FIGS. 8 and 9 , when driving for image display, a fixed black data voltage (Vob) higher than the pure black data voltage (Vob) is applied to the corresponding subpixel so that a black grayscale can be expressed in any subpixel included in the dithering black processing area. A dithering black data voltage (Vdb) corresponding to the voltage is supplied.

That is, the dithering black data voltage Vdb corresponding to a fixed voltage higher than the pure black data voltage Vob is applied to the first node N1 corresponding to the gate node of the driving transistor DRT in the corresponding subpixel.

Also, when driving for image display, the reference voltage Vref may be applied to the second node N2 of the driving transistor DRT.

The dithering black data voltage Vdb is set such that a difference between the dithering black data voltage Vdb and the reference voltage Vref is smaller than the threshold voltage of the driving transistor DRT.

Therefore, since the potential difference Vgs between the first node N1 and the second node N2 of the driving transistor DRT is smaller than the threshold voltage of the driving transistor DRT, the driving transistor DRT is turned off and corresponding Subpixels do not emit light.

However, when the temperature rises and is out of the room temperature range, a phenomenon in which the threshold voltage of the driving transistor DRT shifts in a negative direction may occur.

That is, when the temperature rises and goes out of the room temperature range, the threshold voltage of the driving transistor DRT may decrease.

Therefore, when the temperature rises, the potential difference Vgs between the first node N1 and the second node N2 of the driving transistor DRT increases due to a negative shift phenomenon of the threshold voltage of the driving transistor DRT. ) may result in a situation in which the threshold voltage or more is exceeded.

As a result, as shown in FIGS. 8 and 9 , even though the dithering black data voltage Vdb for turning off the driving transistor DRT is applied to the gate node of the driving transistor DRT, the driving transistor ( DRT) can be unnecessarily turned on.

Therefore, in a high-temperature situation outside the normal temperature range as the temperature rises, the driving transistor DRT is turned on instead of being turned off by the dithering black data voltage Vdb, and current is supplied to the organic light emitting diode OLED. , the corresponding subpixel may unnecessarily emit light.

Therefore, as shown in FIG. 10, when dithering black processing is performed in a high-temperature situation, the subpixels in which the driving transistor DRT that is unnecessarily turned on emits light unnecessarily, and the corresponding dithering black processing area, Black gradation may not be expressed and may be displayed in a color slightly brighter than black.

In a high-temperature situation, a high-temperature black anomaly phenomenon in which an abnormal image cannot accurately express a low grayscale may significantly degrade image quality.

Therefore, when the dithering black data voltage Vdb is supplied to the subpixels in the unit area to be subjected to the dithering black process, it is necessary to supply the dithering black data voltage Vdb to accurately turn each subpixel into a non-emission state.

Accordingly, in the present embodiments, in supplying the dithering black data voltage Vdb to the subpixels in the unit area to be subjected to the dithering black process, in order to prevent the high-temperature black abnormality, each subpixel accurately enters a non-emission state. It provides a method of supplying a dithering black voltage (Vdb) that

As such, a temperature-based voltage change method in which the temperature of the organic light emitting display device 100 is sensed and the dithering black voltage (Vdb) is changed to a low level when the sensed temperature rises beyond the room temperature range, and a sub-system without temperature detection is provided. After supplying the dithering black voltage Vdb to a pixel, sensing whether a subpixel emits light and changing the dithering black voltage Vdb according to the sensing result may be a sensing-based voltage changing method or the like.

In addition, a high-temperature black anomaly may be prevented by using a combination of a temperature-based voltage change method and a sensing-based voltage change method.

Below, referring to FIGS. 11 to 19 , a high-temperature black anomaly phenomenon method based on a temperature-based voltage change method will be described.

11 is a diagram illustrating a system for changing the dithering black data voltage Vdb according to temperature in the organic light emitting display device 100 according to the present embodiments. However, below, the dithering black data voltage Vdb is referred to as the black data voltage Vdb.

Referring to FIG. 11 , the black data voltage Vdb supplied to a plurality of specific subpixels among a plurality of subpixels may change according to temperature.

As such, by changing the black data voltage Vdb according to the temperature, an unnecessary turn-on phenomenon of the driving transistor DRT that occurs at a high temperature may be prevented, thereby preventing a high-temperature black abnormal phenomenon.

The black data voltage Vdb supplied to a plurality of specific subpixels may be changed lower as the temperature increases.

In this way, as the temperature increases, the black data voltage Vdb supplied to a plurality of specific subpixels is changed to be low, so that the threshold voltage Vgs of the driving transistor DRT in the characteristic subpixel is shifted in the negative direction as the temperature rises. It is possible to lower the voltage, and thus, the driving transistor DRT can be prevented from being turned on undesirably.

On the other hand, the plurality of specific subpixels mentioned above are located in a unit area (dithering black processing area) in which the number of subpixels to be expressed in black gradation is greater than a certain number among the plurality of unit areas of the organic light emitting display panel 110. It may be subpixels (subpixels arranged in M rows and N columns).

As described above, in order to prevent the high-temperature black phenomenon, the dithering black process is performed by changing the black data voltage (Vdb) for each unit area including subpixels arranged in M rows and N columns, thereby significantly increasing driving efficiency. can give

Meanwhile, the black data voltage Vdb supplied to the plurality of specific subpixels may be higher than the black data voltage supplied to subpixels other than the plurality of specific subpixels.

Here, the black data voltage supplied to a subpixel that is not a plurality of specific subpixels subject to dithering black processing may be a pure black data voltage (Vob).

Accordingly, during dithering, a vertical line noise phenomenon caused by a large difference between a data voltage of 0 gray level and a data voltage of 1 gray level can be prevented.

As described above, the black data voltage (Vdb) exceeds the pure black data voltage (Vob) corresponding to the black data voltage supplied to a subpixel other than a plurality of specific subpixels, and a plurality of specific subpixels at room temperature. The dithering black data voltage (Vdb) supplied to may be changed within the range specified below.

Referring to FIG. 11 , the temperature mentioned above may be an internal temperature of the organic light emitting display device 100 .

The controller 140 may also receive information about temperature.

As a method for inputting temperature information to the controller 140, the temperature information may be input to the controller 140 according to a user input, or a temperature sensing configuration inside the organic light emitting display device 100 may be utilized. Information on the temperature may be input to the controller 140 .

When using the temperature sensing configuration, the organic light emitting display device 100 may further include a temperature sensor 1100 as a temperature sensing configuration for sensing internal temperature of the organic light emitting display device 100 .

The controller 140 changes the black data (digital voltage value) to be supplied to each specific sub-pixel based on the temperature T sensed by the temperature sensor 1100 and provides it to the data driver 120,

The data driver 120 may convert the black data provided from the controller 140 into a black data voltage (Vdb, an analog voltage value) and output the converted black data voltage (Vdb, an analog voltage value) to a data line DL connected to each specific subpixel.

As described above, by changing the black data voltage Vdb based on the temperature sensed through the temperature sensor 1100, the high-temperature black anomaly can be effectively and accurately prevented.

12 is a graph showing the black data voltage Vdb versus temperature when the dithering black data voltage Vdb is changed according to the temperature in the organic light emitting display device 100 according to the present embodiments.

FIG. 13 is a Vgs-Ids graph showing that an unnecessary light emission phenomenon is prevented according to a process of changing the dithering black data voltage Vdb according to temperature in the organic light emitting display device 100 according to the present exemplary embodiments.

Referring to FIGS. 12 and 13 , the black data voltage Vdb supplied to a plurality of specific subpixels included in the dithering black processing region may change lower as the temperature increases.

When the dithering black process is performed with the black data voltage Vdb corresponding to Vdb1 at the temperature T1 (temperature within the room temperature range), the corresponding specific subpixels do not emit light and can accurately express the black gradation.

However, when a temperature rise occurs from the temperature T1 (temperature within the room temperature range) to the temperature T2 (temperature higher than the room temperature range), the threshold voltage of the driving transistor DRT in the specific subpixel shifts in the negative direction.

Accordingly, in FIG. 13, the characteristic curve is shifted to the left in the Vgs-Ids graph.

Therefore, when dithering black processing is performed using the black data voltage Vdb corresponding to Vdb1 as it is, the driving transistor DRT in the specific subpixel is turned on unnecessarily instead of being turned off, resulting in an organic light emitting diode ( OLED) emits light, and the corresponding specific sub-pixel is expressed in a color brighter than black.

Referring to FIGS. 12 and 13 , according to the present embodiments, when the temperature of T2 is sensed and the black data voltage Vdb is changed to Vdb2 corresponding to the temperature of T2 to be lower than Vdb1, the driving transistor DRT in the specific subpixel ) is turned on as desired, and the corresponding specific subpixel expresses the desired black. Thus, the high-temperature black anomaly can be prevented.

The aforementioned temperature sensor 1100 may be positioned anywhere inside the organic light emitting display device 100 .

For example, the temperature sensor 1100 may be located on a printed circuit board included in the organic light emitting display device 100 .

14 is for explaining a method of utilizing information 1410 of a memory 1400 when changing the dithering black data voltage Vdb according to the detected temperature in the organic light emitting display device 100 according to the present embodiments. it is a drawing

Referring to FIG. 14 , the organic light emitting display device 100 according to the present embodiments includes a memory 1400 that stores memory information 1410 including information on black data for each temperature or black data voltage for each temperature. can include more.

The memory information 1410 includes information on a correspondence relationship between black data (digital voltage value) or black data voltage (analog voltage value) according to temperature change, as shown in FIG. 14, or defines a correspondence relationship. It can contain information about equations or graphs.

Black data (digital voltage value) or black data voltage (analog voltage value) according to temperature change included in the memory information 1410 may be different for each organic light emitting display panel 110, and the corresponding organic light emitting display panel 110 It may be predetermined information in consideration of a change in the threshold voltage of the driving transistor DRT according to a change in temperature in .

The controller 140 may change black data to be supplied to each specific subpixel by determining black data corresponding to the sensed temperature by referring to the black data for each temperature or the black data voltage for each temperature stored in the memory 1400. .

When determining the black data corresponding to the sensed temperature, the black data corresponding to the sensed temperature is extracted and determined from the memory information 1410, or the black data corresponding to the sensed temperature is determined by any relationship (a relational expression between temperature and black data). ) can also be calculated through a calculation process using

As described above, the controller 140 determines black data corresponding to the detected temperature by referring to information on black data (black data voltage) for each temperature stored in the memory 1400, thereby providing black data more rapidly. can decide

Meanwhile, even if the black data voltage is changed using the temperature sensor 1100 and the memory 1400, the corresponding driving transistor DRT may not be accurately turned off by the changed black data voltage.

Accordingly, the high-temperature black anomaly may be more accurately prevented by more accurately correcting the black data voltage changed according to the temperature detection by additionally using the sensing-based voltage changing method.

This will be described with reference to FIGS. 15, 16, 17A and 17B.

15 illustrates a method of correcting, when the dithering black data voltage Vdb changed by using information of the memory 1400 according to the detected temperature is not correct in the organic light emitting display device 100 according to the present embodiments. It explains and shows a sensing circuit for this method.

Referring to FIG. 15 , the organic light emitting display device 100 according to the present embodiments detects whether or not each specific subpixel included in a unit area to be subjected to dithering black processing emits light, and sends the detection result to the controller 140. It may further include a sensing circuit 1500 provided.

Here, the detection result may include, for example, identification information of each specific subpixel and information on whether each specific subpixel emits light or identification information of a specific subpixel that emits light.

The detection result may further include information on the light emission level (eg, amount of current) of a specific subpixel that emits light.

Based on the detection result of the sensing circuit 1500, the controller 140 may correct black data so that a specific subpixel does not emit light, and output the corrected black data to the source driver integrated circuit (SDIC) in the data driver 120.

As described above, even if the black data voltage Vdb is changed by using the temperature sensor 1100 and the memory 1400, the corresponding driving transistor DRT is not accurately turned off by the changed black data voltage Vdb. When a specific subpixel emits light, a high-temperature black anomaly may be more accurately prevented by more accurately correcting the black data voltage Vdb changed according to temperature sensing by additionally using a sensing-based voltage changing method.

The aforementioned sensing circuit 1500 may be included inside the data driver 120 or may be disposed on a source printed circuit board or a control printed circuit board.

FIG. 16 is a diagram illustrating a current sensor 1600 used when a dithering black data voltage (Vdb) is corrected in the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 16 , the sensing circuit 1500 may include a current sensor 1600 electrically connected to a driving voltage line DVL that transmits a driving voltage EVDD to a specific subpixel.

The current sensor 1600 may measure the current value I flowing through the driving voltage line DVL and output the measured current value I as a sensing result.

The controller 140 may determine that a corresponding specific subpixel emits light when the measured current value I exceeds a predetermined threshold value.

The controller 140 may correct the black data so that the current value I flowing through the driving voltage line DVL is equal to or less than the threshold value, and output the corrected black data to the data driver 120 .

When black data is corrected, existing black data can be corrected to be high or small.

Accordingly, the corrected black data voltage Vdb may be higher or lower than the black data voltage Vdb before correction.

As described above, the corresponding driving transistor DRT is not accurately turned off by the black data voltage Vdb through the current sensor 1600 and more accurately corrects the specific black data voltage Vdb, so that the black data voltage Vdb is higher than the high temperature. phenomenon can be prevented more precisely.

17A and 17B are diagrams illustrating installation of the current sensor 1600 used in the process of correcting the dithering black data voltage Vdb in the organic light emitting display device 100 according to the present embodiments.

As shown in FIG. 17A , the current sensor 1600 may be commonly connected to two or more driving voltage lines DVL.

If one current sensor 1600 is commonly connected to all driving voltage lines DVL included in the organic light emitting display panel 110, the organic light emitting display device 100 has one current sensor 1600 exist.

When one current sensor 1600 is commonly connected to two or more driving voltage lines DVL instead of all driving voltage lines DVL included in the organic light emitting display panel 110, the organic light emitting display device 100 Two or more current sensors 1600 may exist.

As shown in FIG. 17B , the current sensor 1600 may be connected to one driving voltage line DVL.

That is, one current sensor 1600 may be connected to each driving voltage line DVL.

As shown in FIG. 17A , in the case of using one current sensor 1600 connected to several driving voltage lines DVL, subpixels unnecessarily emitting light can be rapidly sensed without a large burden of sensing processing. On the other hand, in the case of using the current sensors 1600 connected to each driving voltage line DVL as shown in FIG. 17B, it is possible to accurately distinguish and sense subpixels that unnecessarily emit light and subpixels that do not.

The driving method for preventing the high-temperature black anomaly described above will be briefly described again below.

18 is a flowchart of a method of driving the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 18 , the driving method of the organic light emitting display device 100 according to the present embodiments includes a temperature sensing step (S1810) of sensing the temperature of the organic light emitting display device 100;

A black data voltage changing step ( S1820 ) of changing and supplying the black data voltage Vdb to be supplied to a specific subpixel based on the sensed temperature may be included.

Using the aforementioned driving method, it is possible to prevent a high-temperature black anomaly occurring in a high-temperature situation by changing the black data voltage Vdb according to the temperature.

Referring to FIG. 18 , after the black data voltage changing step ( S1820 ), a black data voltage correcting step ( S1830 ) may be selectively further performed.

In the black data voltage correction step ( S1830 ), when a specific subpixel emits light, the black data voltage Vdb to be supplied to the specific subpixel may be changed (corrected) again.

The black data voltage correction step ( S1830 ) is repeatedly performed, so that the black data voltage that can completely prevent the high-temperature black anomaly can be accurately found.

According to the black data voltage correction step (S1830) described above, even if the corresponding specific subpixel is driven using the black data voltage Vdb changed based on the detected temperature, the corresponding driving transistor ( When a corresponding specific subpixel emits light because the DRT is not accurately turned off, the high-temperature black anomaly can be more accurately prevented by additionally correcting the black data voltage Vdb.

In the black data voltage changing step S1820, the black data voltage Vdb may be changed lower as the sensed temperature increases.

19 is a block diagram of the controller 140 of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 19 , the controller 140 of the organic light emitting display device 100 according to the present embodiments includes a temperature checking unit 1910 that receives information about the sensed temperature, and a specific temperature based on the sensed temperature. A black data control unit 1920 for changing and outputting black data to be supplied to subpixels may be included.

According to the foregoing, it is possible to provide the controller 140 capable of preventing the high-temperature black anomaly.

Referring to FIG. 19 , the black data control unit 1920 may receive a detection signal (sensing result of the sensing circuit 1500) through the detection signal input unit 1930 and correct black data to be supplied to a specific subpixel. .

Here, the detection signal corresponds to a detection result of the sensing circuit 1500 and is a detection result of detecting whether a corresponding specific subpixel emits light.

As described above, even if a corresponding specific subpixel is driven using the black data voltage (Vdb) changed based on the detected temperature, the controller 140 can prevent a high-temperature black anomaly that may occur through subpixel emission sensing. ) can be provided.

Meanwhile, below, a driving method for preventing a high-temperature black anomaly by using a sensing-based voltage changing method rather than a temperature-based voltage changing method will be briefly described.

20 is another flowchart of a method of driving the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 20 , a method of driving the organic light emitting display device 100 according to the present embodiments includes supplying a predetermined initial black data voltage to a specific subpixel (S2010), and supplying the initial black data voltage to a specific subpixel. A step of detecting whether a specific subpixel emits light ( S2020 ) and, if it is detected that the specific subpixel emits light, a step of changing an initial black data voltage and supplying it to the specific subpixel ( S2030 ).

Meanwhile, steps S2010, S2020, and S2030 are repeatedly performed, so that a black data voltage that can completely prevent a high-temperature black anomaly can be accurately found.

Using this driving method, it is possible to directly find a subpixel in which a high-temperature black anomaly occurs through sensing, so that black can be accurately expressed in the corresponding subpixel.

In the case of using the driving method of FIG. 20 , the controller 140 may not have the temperature checking unit 1910 in FIG. 19 .

Meanwhile, below, the method for preventing the high-temperature black anomaly described above can be extended and applied to other gradations other than the black gradation. This case will be briefly described.

An organic light emitting display device 100 according to the present embodiments includes an organic light emitting display panel 110 in which a plurality of subpixels defined by a plurality of data lines DL and a plurality of gate lines GL are arranged; It may include a data driver 120 outputting data voltages to a plurality of data lines DL, a controller 140 controlling the data driver 120, and the like.

A data voltage of a specific grayscale supplied to all or part of a plurality of subpixels may be changed according to temperature.

As described above, when a subpixel cannot accurately express a specific desired grayscale due to a temperature change, the data voltage of the specific grayscale is changed in consideration of the temperature change so that the corresponding subpixel can accurately express the specific desired grayscale. can

A data voltage of a specific gray level may be changed in inverse proportion to temperature.

Accordingly, it is possible to prevent a high-temperature black abnormal phenomenon that may occur when the threshold voltage of the driving transistor DRT shifts in a negative direction due to a high-temperature phenomenon.

The data voltage of a specific grayscale may be a black data voltage Vdb corresponding to a black grayscale.

Accordingly, black expressiveness of the organic light emitting display device 100 can be improved.

According to the present embodiments as described above, it is possible to provide the controller 140, the organic light emitting display device 100, and the driving method capable of improving low grayscale expression in a low grayscale region.

In addition, according to the present embodiments, the controller 140 and the organic light emitting display device can prevent low gradation expressiveness (in particular, black expressive power) from deteriorating due to a change in transistor characteristics on the organic light emitting display panel according to a temperature change. (100) and its driving method can be provided.

In addition, according to the present embodiments, it is possible to provide the controller 140, the organic light emitting display device 100, and a driving method thereof that can improve black expressiveness by changing a black data voltage according to a change in temperature.

In addition, according to the present embodiments, the controller 140, which can improve image quality by preventing a high-temperature black anomaly in which the threshold voltage of the driving transistor shifts in a negative direction as the temperature rises and unnecessarily emits light from sub-pixels; An organic light emitting display device 100 and a driving method thereof may be provided.

The above description and accompanying drawings are only illustrative of the technical idea of the present invention, and those skilled in the art can combine the configuration within the range that does not deviate from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

100: organic light emitting display device
110: organic light emitting display panel
120: data driver
130: gate driver
140: controller

Claims (19)

an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged;
a data driver outputting data voltages to the plurality of data lines; and
A controller controlling the data driver;
A first black data voltage supplied to a plurality of specific subpixels among the plurality of subpixels is higher than a second black data voltage supplied to other subpixels excluding the plurality of specific subpixels among the plurality of subpixels;
The first black data voltage supplied to the plurality of specific subpixels among the plurality of subpixels is changed according to temperature so that a difference from the second black data voltage is changed, and the plurality of specific black data voltages among the plurality of subpixels are changed. The organic light emitting display device of claim 1 , wherein the second black data voltage supplied to subpixels other than the subpixel does not change according to the temperature. According to claim 1,
The black data voltage supplied to the plurality of specific subpixels is changed lower as the temperature increases. delete According to claim 1,
The plurality of specific subpixels,
An organic light emitting display device comprising subpixels in a unit area of which the number of subpixels to be expressed in black gradation among a plurality of unit areas of the organic light emitting display panel is greater than or equal to a certain number. According to claim 1,
a temperature sensor for sensing an internal temperature of the organic light emitting display;
The controller,
Based on the detected temperature, black data to be supplied to each specific subpixel is changed and provided to the data driver;
The data driver,
An organic light emitting display device that converts the black data provided from the controller into the black data voltage and outputs the converted black data voltage to a data line connected to each specific subpixel. According to claim 5,
The controller,
Based on the input image data for each of the plurality of subpixels,
The organic light emitting display device that determines the plurality of specific subpixels to be subjected to dithering black processing among the plurality of subpixels. According to claim 6,
The entire area of the organic light emitting display panel is divided into two or more unit areas;
Each unit area is composed of subpixels in M rows and N columns, where one of M and N is a natural number greater than or equal to 1 and the other is a natural number greater than or equal to 2;
The controller,
Determine whether or not to process dithering black for each unit area composed of subpixels in M rows and N columns;
For each unit area,
Based on the input image data of each of the subpixels in the M row and N column included in the unit area, if the number of subpixels to be expressed as 0 (Zero) grayscale is greater than or equal to the predetermined value, the corresponding unit The area is determined as a dithering black processing area,
and determining subpixels in row M and column N included in the dithering black processing area as the plurality of specific subpixels. According to claim 5,
Further comprising a memory for storing black data for each temperature or black data voltage for each temperature,
The controller,
Referring to the black data for each temperature or the black data voltage for each temperature stored in the memory,
An organic light emitting display device that changes black data to be supplied to each specific sub-pixel by determining black data corresponding to the sensed temperature. According to claim 5,
Further comprising a sensing circuit for detecting whether or not the specific subpixel emits light and providing a detection result to the controller;
The controller,
An organic light emitting display device that corrects and outputs black data so that the specific subpixel does not emit light based on the detection result. According to claim 9,
The sensing circuit,
A current sensor electrically connected to a driving voltage line for transmitting a driving voltage to the specific subpixel;
The current sensor,
Measuring a current value flowing through the driving voltage line and outputting the measured current value as the sensing result;
The controller,
When the measured current value exceeds the threshold value, it is determined that the specific subpixel emits light,
An organic light emitting display device that corrects and outputs black data so that a current value flowing through the driving voltage line is less than or equal to the threshold value. According to claim 10,
The current sensor,
connected with one driving voltage line, or
An organic light emitting display device connected together with two or more driving voltage lines. A method of driving an organic light emitting display device including an organic light emitting display panel in which a plurality of subpixels are arranged,
A first black data voltage supplied to a plurality of specific subpixels among the plurality of subpixels is higher than a second black data voltage supplied to other subpixels excluding the plurality of specific subpixels among the plurality of subpixels;
The driving method of the organic light emitting display device,
a temperature sensing step of sensing a temperature of the organic light emitting display device; and
a black data voltage changing step of changing and supplying the first black data voltage to be supplied to the plurality of specific subpixels based on the sensed temperature;
In the changing of the black data voltage, a difference between the first black data voltage and the second black data voltage is changed based on the sensed temperature, and the plurality of specific subpixels among the plurality of subpixels are changed. The method of driving an organic light emitting display device in which the second black data voltage supplied to other subpixels except for is not changed based on the sensed temperature. According to claim 12,
After the step of changing the black data voltage,
The method of driving the organic light emitting display device further comprising a black data voltage correction step of changing a black data voltage to be supplied to the specific subpixel again when the specific subpixel emits light. A controller controlling a voltage supplied to an organic light emitting display panel in which a plurality of subpixels are arranged,
A first black data voltage supplied to a plurality of specific subpixels among the plurality of subpixels is higher than a second black data voltage supplied to other subpixels excluding the plurality of specific subpixels among the plurality of subpixels;
The controller,
a temperature confirmation unit that receives information about the sensed temperature; and
a black data control unit configured to change and output the first black data to be supplied to the plurality of specific subpixels based on the sensed temperature;
The first black data voltage supplied to the plurality of specific subpixels among the plurality of subpixels is changed according to the sensed temperature so that a difference from the second black data voltage is changed, and the difference between the first black data voltage and the second black data voltage is changed. The controller of the organic light emitting display device, wherein the second black data voltage supplied to subpixels other than a plurality of specific subpixels does not change according to the sensed temperature. According to claim 14,
The black data controller,
A controller of an organic light emitting display device that receives a detection signal and corrects black data to be supplied to the specific subpixel. an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged;
a data driver outputting data voltages to the plurality of data lines; and
A controller controlling the data driver;
A data voltage of a specific grayscale supplied to a plurality of specific subpixels among the plurality of subpixels is changed according to a change in temperature;
A data voltage of a specific grayscale supplied to the plurality of specific subpixels among the plurality of subpixels is a first black data voltage corresponding to a black grayscale, and the first black data voltage is the plurality of specific grayscale data voltages among the plurality of subpixels. higher than the second black data voltage supplied to other subpixels except for the subpixel;
The first black data voltage supplied to the plurality of specific subpixels among the plurality of subpixels is changed according to the temperature so that a difference from the second black data voltage is changed, and the plurality of black data voltages among the plurality of subpixels are changed. The organic light emitting display device of claim 1 , wherein the second black data voltage supplied to subpixels other than a specific subpixel does not change according to temperature. According to claim 16,
The data voltage of the specific gray level is changed in inverse proportion to temperature. delete A method of driving an organic light emitting display device including an organic light emitting display panel in which a plurality of subpixels are arranged,
A first initial black data voltage supplied to a plurality of specific subpixels among the plurality of subpixels is higher than a second initial black data voltage supplied to other subpixels excluding the plurality of specific subpixels among the plurality of subpixels. ,
The driving method of the organic light emitting display device,
supplying the first initial black data voltage to the plurality of specific subpixels;
detecting whether the plurality of specific subpixels supplied with the first initial black data voltage emit light; and
a voltage changing step of changing the first initial black data voltage and supplying the voltage to the plurality of specific subpixels when it is sensed that the plurality of specific subpixels emit light;
In the voltage changing step, as the first initial black data voltage is changed, a difference from the second initial black data voltage is changed, and other subpixels other than the plurality of specific subpixels among the plurality of subpixels are changed. A method of driving an organic light emitting display device in which the supplied second initial black data voltage is not changed.

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