KR20170064176A - Controller, organic light emitting display panel, organic light emitting display device, and the method for driving the organic light emitting display device - Google Patents

Abstract

More particularly, the present invention relates to a sensing and compensation technique in an organic light emitting diode display, and more particularly, to a sensing and driving technique for sensing a characteristic value of a driving transistor in real time during image driving, An organic light emitting diode (OLED) display panel, and a method of driving the organic light emitting display panel.

Description

Technical Field [0001] The present invention relates to an organic light emitting display, a controller, an organic light emitting display panel, an organic light emitting display, and a method of driving the same. BACKGROUND ART [0002]

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

2. Description of the Related Art In recent years, an organic light emitting diode (OLED) display device that has been popular as a display device has advantages of high response speed, high luminous efficiency, high brightness, and wide viewing angle by using an organic light emitting diode (OLED)

Such an organic light emitting display device arranges subpixels including organic light emitting diodes in a matrix form and controls the brightness of subpixels selected by the scan signals according to the gradation of data.

Each sub-pixel of the organic light emitting diode display may include an organic light emitting diode and a driving transistor for driving the organic light emitting diode.

On the other hand, the driving transistors in each sub-pixel have inherent characteristic values such as threshold voltage and mobility. The inherent characteristic values of each of the driving transistors can be changed by the progress of the degradation according to the driving time.

For this reason, a difference in the degree of deterioration between the driving transistors occurs due to the difference in driving time between the driving transistors in each sub-pixel, and a characteristic value deviation between the driving transistors may also occur.

Such a characteristic value deviation between the driving transistors may cause a luminance deviation between the subpixels, which may be a main factor causing image quality degradation.

Accordingly, various techniques have been developed to sense and compensate the characteristic values between the driving transistors.

On the other hand, it takes a long time to sense the characteristic values of the driving transistors in all the sub-pixels arranged in the organic light emitting display panel, in particular, the threshold voltage. Therefore, it is difficult to select the sensing timing for sensing the characteristic value of the driving transistor have.

It is an object of the embodiments of the present invention to provide a controller capable of real-time sensing timing for real-time sensing of a characteristic value of a driving transistor during image driving and capable of proceeding sensing operation at a secured real-time sensing timing, And a driving method thereof.

It is another object of the present embodiments to provide a controller that enables real-time sensing timing by determining an interval during which a screen is switched by user input during image driving as a sensing driving interval, and enables sensing driving in real- , An organic light emitting display panel, an organic light emitting display, and a driving method thereof.

Another object of the present invention is to provide a method and apparatus for determining a screen switching period in which a screen is switched to a black screen as a sensing driving period during video driving to secure real time sensing timing, A controller, an organic light emitting display panel, an organic light emitting display, and a driving method thereof.

In one aspect, the present embodiments provide an organic light emitting display device comprising: an organic light emitting display panel in which organic light emitting diodes and driving transistors are arranged for respective subpixels; a screen switching period determining unit for determining a screen switching period; A sensing unit for sensing a voltage of a sensing line electrically connected to each sub pixel and generating sensing data based on the sensed voltage during a screen switching period, And the compensation value is calculated based on the sensing data for each sub-pixel when the sensing data for the pixel is generated, thereby providing an organic light emitting display including the compensating unit.

The screen switching period may be determined by a channel changing signal according to user input or a screen UI (User Interface) changing signal.

The screen switching period may be a sensing driving period determined according to preset real-time sensing timing information. A predetermined number of black frames can be driven during the sensing driving period.

According to another aspect of the present invention, there is provided an organic light emitting diode display including a screen switching period determining unit for determining a screen switching period and a driving control unit for controlling sensing driving for sensing a characteristic value of a driving transistor during a screen switching period. A controller of the apparatus can be provided.

According to another aspect of the present invention, there is provided a method of driving an OLED display device including an organic light emitting display panel in which organic light emitting diodes and driving transistors are arranged for each subpixel, , A step of determining a screen switching period, and a step of sensing driving for sensing a characteristic value of the driving transistor during a screen switching period, and the like.

According to another aspect of the present invention, there is provided an organic light emitting display comprising: an organic light emitting diode; a driving transistor for driving the organic light emitting diode; a sensing transistor connected between a first node of the driving transistor and the sensing line; A storage capacitor connected between the first node and the second node of the driving transistor, and the like.

In such an organic light emitting display panel, the sensing line may have a voltage rising from a reference voltage according to sensing driving during a screen switching period.

According to the exemplary embodiments of the present invention described above, it is possible to provide a controller that ensures real-time sensing timing for real-time sensing of the characteristic value of the driving transistor during image driving and allows sensing driving to be performed at a secured real- A panel, an organic light emitting display, and a driving method thereof.

In addition, according to the present exemplary embodiments, a period during which a screen is switched by user input during a video driving is determined as a sensing driving period to ensure real-time sensing timing, and a sensing driving timing can be secured in real time A controller, an organic light emitting display panel, an organic light emitting display, and a driving method thereof.

In addition, according to the embodiments, a screen switching period in which the screen is switched to the black screen as the sensing driving period during the video driving is determined to ensure the real-time sensing timing, and the sensing operation is performed while driving the black frame at the secured real- A controller, an organic light emitting display panel, an organic light emitting display, and a driving method thereof that can be performed in real time can be provided.

1 is a system configuration diagram of an organic light emitting display according to the present embodiments.
2 is an exemplary view illustrating a sub-pixel structure of an OLED display according to an exemplary embodiment of the present invention. Referring to FIG.
3 is an exemplary view illustrating another subpixel structure and a compensation circuit of the OLED display according to the present embodiments.
4 is a view for explaining a threshold voltage sensing method of the organic light emitting display according to the present embodiments.
5 is a view for explaining a mobility sensing method of the OLED display according to the present embodiments.
6 is a timing chart illustrating the sensing timing of the OLED display according to the present invention.
FIG. 7 is a diagram illustrating a method for securing real-time sensing timing of the organic light emitting display according to the present embodiments and a sensing system therefor.
8 to 10 are diagrams for explaining a method for securing real-time sensing timing based on user triggering according to the present embodiments.
11 to 15 are diagrams for explaining a method for securing real-time sensing timing based on system triggering according to the present embodiments.
16 is a diagram showing a controller for securing real-time sensing timing according to the present embodiments.
17 is a flowchart illustrating a method of driving an organic light emitting display device for securing real-time sensing timing according to the present embodiments.
18 is a flowchart illustrating a method of driving an organic light emitting display device for securing real-time sensing timing based on user triggering according to the present embodiments.
19 is a flowchart illustrating a method of driving an organic light emitting display for securing real-time sensing timing based on system triggering according to the present embodiments.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the components from other components, and the terms do not limit the nature, order, order, or number of the components. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

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

1, the OLED display 100 according to the present embodiment includes a plurality of data lines DL1 to DLm and a plurality of gate lines GL1 to GLn, A data driver 120 for driving the plurality of data lines DL1 to DLm and a gate driver for driving the plurality of gate lines GL1 to GLn 130, a controller 140 for controlling the data driver 120 and the gate driver 130, and the like.

The controller 140 supplies various control signals to the data driver 120 and the gate driver 130 to control the data driver 120 and the gate driver 130.

The controller 140 starts scanning according to the timing implemented in each frame, switches the input image data input from the outside according to the data signal format used by the data driver 120, and outputs the converted image data , And controls the data driving at a suitable time according to the scan.

The controller 140 may be a timing controller used in a conventional display technology or a control device including a timing controller to perform other control functions.

The data driver 120 drives the plurality of data lines DL1 to DLm by supplying data voltages to the plurality of data lines DL1 to DLm. Here, the data driver 120 is also referred to as a 'source driver'.

The gate driver 130 sequentially drives the plurality of gate lines GL1 to GLn by sequentially supplying scan signals to the plurality of gate lines GL1 to GLn. Here, the gate driver 130 is also referred to as a " scan driver ".

The gate driver 130 sequentially supplies a scan signal of an On voltage or an Off voltage to the plurality of gate lines GL1 to GLn 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 the plurality of data lines DL1 to DLm .

1, the data driver 120 is located only on one side (e.g., on the upper side or the lower side) of the organic light emitting display panel 110, : Upper side and lower side).

1, the gate driver 130 is located only on one side (e.g., the left side or the right side) of the organic light emitting display panel 110. However, the gate driver 130 may be disposed on both sides of the organic light emitting display panel 110 For example, left and right).

The controller 140 described above is capable of outputting various kinds of signals including the vertical synchronization signal Vsync, the horizontal synchronization signal Hsync, the input data enable signal (DE), and the clock signal (CLK) Timing signals from the outside (e.g., the host system).

The controller 140 outputs the converted image data by switching the input image data inputted from the outside in accordance with the data signal format used by the data driver 120 and outputs the converted image data to the data driver 120 and the gate driver 130, A timing signal such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input DE signal and a clock signal and generates various control signals to control the data driver 120 and the gate driver 130, .

For example, in order to control the gate driver 130, the controller 140 generates a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal GOE 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 the shift timing of the scan signal (gate pulse). The gate output enable signal GOE specifies the timing information of one or more gate driver ICs.

In order to control the data driver 120, the controller 140 may further include a source start pulse (SSP), a source sampling clock (SSC), a source output enable signal (SOE) And outputs various data control signals (DCS: Data Control Signals).

Here, the source start pulse SSP controls the 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 for controlling sampling timing of data in each of the source driver integrated circuits. The source output enable signal SOE controls the output timing of the data driver 120.

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

Each source driver integrated circuit (SDIC) is connected to a bonding pad of the organic light emitting display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) Or may be directly disposed on the organic light emitting display panel 110, and may be integrated and disposed on the organic light emitting display panel 110, as the case may be. In addition, each source driver integrated circuit (SDIC) may be implemented by a chip on film (COF) method, which is mounted on a film connected to the organic light emitting display panel 110.

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.

Each source driver integrated circuit (SDIC) may further include an analog to digital converter (ADC), as the case may be.

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

Each gate driver integrated circuit GDIC may be connected to a bonding pad of the organic light emitting display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) ) Type and may be directly disposed on the organic light emitting display panel 110 or may be integrated on the organic light emitting display panel 110 as the case may be. In addition, each gate driver IC (GDIC) may be implemented by a chip on film (COF) method, which is mounted on a film connected to the organic light emitting display panel 110.

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

The OLED display 100 according to the present embodiments includes at least one source printed circuit board (S-PCB) necessary for circuit connection to at least one source driver IC (SDIC) And a control printed circuit board (C-PCB) for mounting control components and various electric devices.

At least one source driver integrated circuit (SDIC) may be mounted on at least one source printed circuit board (S-PCB), or a film on which at least one source driver integrated circuit (SDIC) is mounted may be connected.

The control printed circuit board (C-PCB) is provided with a controller 140 for controlling the operation of the data driver 120 and the gate driver 130 and the like, and a controller 140 for controlling operations of the organic light emitting display panel 110, the data driver 120, A power controller for controlling various voltages or currents to supply or supply various voltages or currents to the battery 130, or the like.

The at least one source printed circuit board (S-PCB) and the control printed circuit board (C-PCB) may be circuitly connected via at least one connecting member.

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

At least one source printed circuit board (S-PCB) and a control printed circuit board (C-PCB) may be integrated into one printed circuit board.

Each of the subpixels SP disposed in the organic light emitting display panel 110 according to the present embodiment includes an organic light emitting diode (OLED) and a circuit element such as a driving transistor for driving the organic light emitting diode .

The types and the number of the circuit elements constituting each subpixel SP can be variously determined depending on the providing function, the design method, and the like.

2 is an exemplary view of a sub-pixel structure of the OLED display 100 according to the present embodiments.

2, each of the sub-pixels SP includes an organic light emitting diode (OLED), an organic light emitting diode (OLED) A switching transistor SWT for transmitting a data voltage to a second node N2 corresponding to a gate node of the driving transistor DRT; And a storage capacitor (Cstg) that holds a data voltage corresponding to the voltage or a voltage corresponding thereto for one frame time.

The organic light emitting diode OLED may include a first electrode (e.g., an anode electrode), an organic layer, and a second electrode (e.g., a cathode electrode).

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

The first node N1 of the driving transistor DRT may be electrically connected to the first electrode of the organic light emitting diode OLED and may be a source node or a drain node. The second node N2 of the driving transistor DRT may be electrically connected to the source node or the drain node of the switching transistor SWT and may be a gate node. The third node N3 of the driving transistor DRT may be electrically connected to a driving voltage line DVL for supplying a driving voltage EVDD and may be a drain node or a source node.

The driving transistor DRT and the switching transistor SWT may be implemented as an n-type or a p-type as illustrated in FIG.

The switching transistor SWT is electrically connected between the data line DL and the second node N2 of the driving transistor DRT and can be controlled by receiving the scan signal SCAN through the gate line to the gate node .

The switching transistor SWT may be turned on by the scan signal SCAN to transfer the data voltage Vdata supplied from the data line DL to the second node N2 of the driving transistor DRT.

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

The storage capacitor Cstg is not a parasitic capacitor (e.g., Cgs or Cgd) which is an internal capacitor existing between the first node N1 and the second node N2 of the driving transistor DRT, And is an external capacitor intentionally designed outside the driving transistor DRT.

In the OLED display 100 according to the present embodiment, as the driving time of each sub-pixel SP becomes longer, the driving voltage of the organic light emitting diode OLED, the driving transistor DRT, Degradation can proceed.

Accordingly, inherent characteristic values (e.g., threshold voltage, mobility, etc.) of the circuit elements such as the organic light emitting diode OLED and the driving transistor DRT can be changed.

Such a change in the characteristic value of the circuit element causes the luminance change of the corresponding subpixel. Therefore, the change in the characteristic value of the circuit element can be used in the same concept as the change in luminance of the subpixel.

In addition, the degree of change in the characteristic value between the circuit elements may be different depending on the degree of deterioration of each circuit element.

Such a characteristic value deviation between the circuit elements causes a luminance deviation between the subpixels. Therefore, the characteristic value deviation between the circuit elements can be used in the same concept as the luminance deviation between the subpixels.

The above-described subpixel luminance variation and subpixel luminance variation may cause problems such as degradation of the accuracy with respect to the luminance expression power of the subpixels or occurrence of screen abnormal phenomenon.

Here, the characteristic value of a circuit element (hereinafter also referred to as a "subpixel characteristic value") may include, for example, a threshold voltage and a mobility of a driving transistor DRT, May include the threshold voltage of the transistor.

The OLED display 100 according to the present embodiment has a sensing function for sensing a sub-pixel luminance change and a sub-pixel luminance deviation (a characteristic value change of a circuit element and a characteristic value deviation between circuit elements) The compensation function for compensating the sub-pixel luminance variation and the sub-pixel luminance deviation can be provided.

The organic light emitting diode display 100 according to the present embodiment includes a subpixel structure and a sensing and compensation structure corresponding thereto to provide a sensing and compensating function for a subpixel luminance change and a luminance deviation between subpixels Compensation circuit.

3 is an exemplary view of another sub-pixel structure and a compensation circuit of the OLED display 100 according to the present embodiments.

Referring to FIG. 3, each sub-pixel disposed in the organic light emitting display panel 110 according to the present exemplary embodiment includes an organic light emitting diode OLED, a driving transistor DRT, a switching transistor SWT, In addition to the capacitor Cstg, it may further include a sensing transistor (SENT).

3, the sensing transistor SENT is electrically connected between a first node N1 of the driving transistor DRT and a sensing line SL that supplies a reference voltage Vref, And may be controlled by receiving a sensing signal SENSE, which is a kind of a scan signal.

The sensing transistor SENT is turned on by the sensing signal SENSE and applies the reference voltage Vref supplied through the sensing line SL to the first node N1 of the driving transistor DRT.

Also, the sensing transistor SENT may be utilized as one of the voltage sensing paths for the first node N1 of the driving transistor DRT.

Meanwhile, the scan signal SCAN and the sense signal SENSE may be separate gate signals. In this case, the scan signal SCAN and the sense signal SENSE may be respectively applied to the gate node of the switching transistor SWT and the gate node of the sensing transistor SENT through another gate line.

In some cases, the scan signal SCAN and the sense signal SENSE may be the same gate signal. In this case, the scan signal SCAN and the sense signal SENSE may be commonly applied to the gate node of the switching transistor SWT and the gate node of the sensing transistor SENT through the same gate line.

Referring to FIG. 3, the organic light emitting display 100 according to the present embodiment senses a deviation between a sub-pixel characteristic value (a characteristic value of the driving transistor, a characteristic of the organic light emitting diode) and / A memory unit 320 for storing sensing data, a compensation unit 320 for compensating a variation between sub-pixel characteristic values and / or sub-pixel characteristic values using sensing data, a sensing unit 310 for outputting sensing data, (330), and the like.

The sensing unit 310 may include at least one analog-to-digital converter (ADC).

Each analog-to-digital converter (ADC) may be included inside the source driver integrated circuit (SDIC) and, in some cases, may be included outside the source driver integrated circuit (SDIC).

The compensation unit 330 may be included inside the controller 140 and, in some cases, may be included outside the controller 140.

The sensing data output from the sensing unit 310 may be, for example, a Low Voltage Differential Signaling (LVDS) data format.

The organic light emitting diode display 100 according to the present exemplary embodiment is configured to control the driving of the driving transistor DRT within the subpixel SP by controlling the voltage application state of the first node N1 in the subpixel SP, And may further include a first switch SW1 and a second switch SW2 in order to control a state required for sensing.

The supply of the reference voltage Vref to the sensing line SL can be controlled through the first switch SW1.

When the first switch SW1 is turned on, the reference voltage Vref is supplied to the sensing line SL and is supplied to the first node N1 of the driving transistor DRT through the sensing transistor SENT, Lt; / RTI >

On the other hand, when the voltage of the first node N1 of the driving transistor DRT becomes a voltage state reflecting the sub-pixel characteristic value, the sensing line SL (which may be of the same potential as the first node N1 of the driving transistor DRT) May also be a voltage state reflecting the sub-pixel characteristic value. At this time, the line capacitor formed on the sensing line SL may be charged with a voltage reflecting the sub-pixel characteristic value.

When the voltage of the first node N1 of the driving transistor DRT becomes a voltage state reflecting the sub pixel characteristic value, the second switch SW2 is turned on so that the sensing portion 310 and the sensing line SL Can be connected.

Accordingly, the sensing unit 310 senses the voltage of the sensing line SL, that is, the voltage of the first node N1 of the driving transistor DRT, which reflects the sub-pixel characteristic value.

One such sensing line SL may be arranged for each subpixel column or one for every two or more subpixel columns.

For example, when one pixel is composed of four subpixels (red subpixel, white subpixel, green subpixel, and blue subpixel), the sensing line SL includes four subpixel columns (red subpixel columns, A green subpixel column, a blue subpixel column, a white subpixel column, a green subpixel column, and a blue subpixel column).

When the sensing unit 310 is connected to the sensing line SL, the voltage of the first node N1 of the driving transistor DRT (the voltage of the sensing line SL or the potential of the line capacitor on the sensing line SL) Voltage) is sensed.

The voltage sensed by the sensing unit 310 may be either a voltage value Vdata-Vth or Vdata-? Vth including a threshold voltage Vth or a threshold voltage deviation? Vth of the driving transistor DRT, May be a voltage value for sensing the degree of mobility.

In the following, the threshold voltage sensing drive and the mobility sensing drive for the driving transistor DRT will be briefly described.

4 is a view for explaining a threshold voltage sensing method of the organic light emitting display according to the present embodiments.

4, when the threshold voltage sensing operation of the driving transistor DRT is performed, the first node N1 and the second node N2 of the driving transistor DRT are driven by the reference voltage Vref and the threshold voltage sensing driving (Vdata).

Thereafter, the first node N1 of the driving transistor DRT is floated by turning off the first switch SW1 or the like.

As a result, the voltage of the first node N1 of the driving transistor DRT rises.

The voltage of the first node N1 of the driving transistor DRT rises for a predetermined period of time and then becomes saturated after a predetermined period of time.

The saturated voltage of the first node N1 of the driving transistor DRT may correspond to the difference between the data voltage Vdata and the threshold voltage Vth or the difference between the data voltage Vdata and the threshold voltage deviation Vth .

The sensing unit 310 senses the saturated voltage of the first node N1 of the driving transistor DRT when the voltage of the first node N1 of the driving transistor DRT is saturated.

The voltage Vsen sensed by the sensing unit 310 is a voltage Vdata-Vth obtained by subtracting the threshold voltage Vth from the data voltage Vdata or a voltage Vdata-Vth obtained by subtracting the threshold voltage deviation Vth from the data voltage Vdata Vdata -? Vth).

5 is a view for explaining a mobility sensing method of the OLED display according to the present embodiments.

5, when the mobility sensing operation is performed, the first node N1 and the second node N2 of the driving transistor DRT are respectively connected to the reference voltage Vref and the mobility sensing driving data voltage Vdata Is initialized.

Thereafter, the first node N1 of the driving transistor DRT is floated in accordance with the OFF of the first switch SW1 or the like.

Thus, the voltage of the first node N1 of the driving transistor DRT can rise.

The voltage rising rate (the amount of change? V of the voltage rising value with respect to time) of the first node N1 of the driving transistor DRT indicates the current capability, i.e., the mobility, of the driving transistor DRT.

The voltage of the first node N1 of the driving transistor DRT increases more sharply as the driving transistor DRT having a higher current capability (mobility) is.

The sensing unit 310 may sense the voltage of the first node N1 of the driving transistor DRT by sensing the voltage of the sensing line SL after the voltage is raised for a predetermined period of time.

According to the threshold voltage sensing drive or the mobility sensing drive, the sensing unit 310 converts the sensed voltage Vsen to a digital value for threshold voltage sensing or mobility sensing, And outputs the generated sensing data.

The sensing data output from the sensing unit 310 may be stored in the memory unit 320 or may be provided to the compensating unit 330.

The compensation unit 330 may store characteristic values (for example, threshold voltage and mobility) of the driving transistor DRT in the corresponding subpixel or characteristics (e.g., threshold voltage and mobility) of the driving transistor DRT based on the sensing data stored in the memory unit 320 or provided by the sensing unit 310. [ (For example, a change in threshold voltage and a change in mobility) of the characteristic value of the target pixel can be detected and the characteristic value compensation process can be performed.

Here, the change in the characteristic value of the driving transistor DRT means that the current sensing data is changed based on the previous sensing data, or the current sensing data is changed based on the reference sensing data.

Here, when comparing the characteristic value or the characteristic value change between the driving transistors DRT, it is possible to grasp the characteristic value deviation between the driving transistors DRT. When the characteristic value change of the driving transistor DRT means that the current sensing data is changed based on the reference sensing data, the characteristic value deviation (i.e., the sub pixel luminance deviation) between the driving transistors DRT from the characteristic value change of the driving transistor DRT, .

The characteristic value compensation process may include a threshold voltage compensation process for compensating the threshold voltage of the driving transistor DRT and a mobility compensation process for compensating the mobility of the driving transistor DRT.

The threshold voltage compensation process calculates a compensation value for compensating for a threshold voltage or a threshold voltage deviation (threshold voltage variation), stores the calculated compensation value in the memory unit 320, or stores the corresponding video data Data ). ≪ / RTI >

The mobility compensation process calculates a compensation value to compensate for mobility or mobility deviation (mobility change), stores the calculated compensation value in the memory unit 320, or stores the corresponding image data Data ). ≪ / RTI >

The compensation unit 330 may change the image data Data through the threshold voltage compensation process or the mobility compensation process and supply the changed data to the corresponding source driver integrated circuit (SDIC) in the data driver 120.

Accordingly, the source driver integrated circuit (SDIC) converts the data supplied from the compensating unit 330 through the digital-to-analog converter 340 into a data voltage and supplies the data voltage to the corresponding subpixel, Voltage compensation, mobility compensation) is actually performed.

By compensating for the subpixel characteristic value, luminance deviation between the subpixels is reduced or prevented, thereby improving the image quality.

6 is a timing chart illustrating the sensing timing of the OLED display 100 according to the present embodiment.

6, the threshold voltage sensing (Vth Sensing) of the driving transistor DRT in the organic light emitting display 100 according to the present embodiment is the same as the voltage Vth of the first node N1 of the driving transistor DRT Since a saturation time is required, it takes a relatively long time compared to the mobility sensing of the driving transistor DRT.

Considering this point, for example, as shown in FIG. 6, the threshold voltage sensing of the driving transistor DRT may proceed while the image is not driven, after the power-off signal is generated according to user input or the like.

The mobility sensing of the driving transistor DRT can be performed even after the power-off signal has been generated, but it can also proceed during image driving in view of the fact that it takes a short time.

Therefore, as shown in Fig. 6, the mobility sensing of the driving transistor DRT can proceed after the power-on signal occurs.

In addition, as shown in FIG. 6, the mobility sensing of the driving transistor DRT may proceed at every blank time between active times based on the vertical synchronization signal Vsync.

For example, in one blank time, the mobility sensing of the driving transistor DRT in one sub-pixel may proceed, and in some cases, the mobility sensing of the driving transistor DRT in two or more sub- .

On the other hand, after the power-off signal is generated, the screen is in a black state during the sensing operation for sensing the characteristic values of all the subpixels disposed in the organic light emitting display panel 110.

Therefore, the user can not recognize that the sensing drive is in progress.

Accordingly, the AC power in the organic light emitting display 100 is turned off due to the user's unplugging the power plug from the outlet after the power off signal is generated by the user pressing the power off button, or the power supply inside the apparatus. The sensing operation which is proceeding according to the power-off signal can be interrupted.

This phenomenon may result in failure in collecting sensing data for all subpixels or in sensing data due to electric shock.

As a result, the compensation value can not be calculated properly, which may cause a block defect phenomenon or a screen abnormal phenomenon such as a screen uneven phenomenon.

On the other hand, since the sensing operation is performed for a long time even if the AC power in the organic light emitting display 100 is not turned off after the power off signal is generated by the user pressing the power off button, There is also the inconvenience of waiting for a long time to complete.

Therefore, the embodiments of the present invention disclose a real-time sensing timing securing method and sensing system that can advance the sensing operation before the power-off signal is generated without advancing the sensing operation after the power-off signal is generated.

6 (b), since the sensing operation in real time in the real-time sensing timing interval (i.e., the interval before the power-off signal is generated) according to the real-time sensing timing securing method according to the present embodiments proceeds in the screen switching interval, Which is different from the sensing operation performed in the blank section.

The sensing driving in real time in the real-time sensing timing interval ensured by the real-time sensing timing securing method according to the present embodiments may be, for example, threshold voltage sensing driving, and in some cases, have.

7 is a diagram illustrating a method for securing real-time sensing timing of the OLED display 100 and a sensing system therefor according to the present embodiments.

Referring to FIG. 7, the OLED display 100 according to the present embodiment includes a sensing system to provide a method for securing real-time sensing timing.

This sensing system includes a screen switching period determining unit 710 for determining a screen switching period CT and a driving control unit 710 for controlling the sensing driving for sensing the characteristic value of the driving transistor DRT during the screen switching period CT And a sensing line electrically connected to each subpixel SP in which the organic light emitting diode OLED and the driving transistor DRT are disposed in the organic light emitting display panel 110 during a screen switching period CT, The sensing unit 310 senses the voltages of the sub-pixels SL and generates sensed data based on the sensed voltage Vsen. When sensing data for all the sub-pixels SP is generated by the sensing unit 310, And a compensation unit 330 for calculating a compensation value based on the sensing data for each pixel SP.

Here, the screen switching section CT exists before the power-off signal is generated, and exists between the video driving sections.

Also, the screen switching interval CT may not be a blank time interval.

The driving control unit 720 controls the data driver 120 and the gate driver (not shown) so that the sensing operation is progressed every screen switching interval CT and the image driving is progressed during the interval (video driving interval) 130 and the like.

With the above-described sensing system, it is advantageous to obtain sensing data in real time during the image driving by advancing the sensing operation for each screen switching interval (CT) before the power-off signal is generated.

The characteristic value of the driving transistor DRT sensed by the sensing driving progressed every screen transition period CT may be, for example, the threshold voltage Vth of the driving transistor DRT in at least one sub-pixel.

As described above, the sensing driving is performed every screen transition period (CT), so that the threshold voltage (threshold voltage) of the driving transistor DRT of all the sub-pixels arranged in the organic light emitting display panel 110 Can be sensed.

According to the method for securing the real-time sensing timing according to the embodiments described briefly hereinabove, each subpixel SP for which sensing drive is performed for each screen transition period CT, as shown in FIG. 3, A driving transistor DRT for driving the organic light emitting diode OLED; a sensing transistor SENT connected between the first node N1 of the driving transistor DRT and the sensing line SL; A switching transistor SWT connected between the second node N2 and the data line DL of the transistor DRT and a switching transistor SW2 connected between the first node N1 and the second node N2 of the driving transistor DRT. A capacitor Cstg, and the like.

Here, according to the sensing drive (threshold voltage sensing drive or mobility sensing drive), the voltage of the sensing line SL rises at the reference voltage Vref corresponding to the initialization voltage during the screen switching interval CT.

According to the above description, it is possible to provide the organic light emitting display panel 110 in which sensing driving can be performed in real time every screen transition period CT.

On the other hand, the screen change section determining section 710 can determine the screen change section CT in two ways.

The first method for determining the screen transition period (CT) is a user triggering method.

According to the user triggering method, the screen change interval determining unit 710 detects a channel change signal, a screen UI (User Interface) change signal, or the like according to a user input, detects the change, The screen transition period (CT) can be determined until the completion of the screen UI change.

The screen transition period CT refers to a period during which a screen is changed during a channel change or a screen UI change in a screen before a channel change or a screen UI change is performed.

That is, the screen state during the screen transition period CT is a state different from the screen state before the screen change, and is a screen state that the user can visually confirm.

For example, the screen state during the screen transition period CT may be a black screen state or a black screen as a whole, and simple information, symbols, images, etc. may be displayed in some areas.

The second method for determining the screen transition period (CT) is the system triggering method.

According to the system triggering method, the screen switching period determining unit 710 determines the sensing driving period ST determined according to the real-time sensing (RS) timing information as the screen switching period CT).

That is, the image driving period DT and the sensing driving period ST are repeatedly time-divided within a predetermined real-time sensing timing interval within the sensing system, and the time-divided sensing driving interval ST is determined as the screen switching interval CT do.

The screen state during this screen transition period CT may be a black screen state.

The screen transition period CT may be a time length of one frame or more. That is, during the screen switching interval CT, one or more black frames may be driven.

In the black screen or the black frame described in the present specification, black may mean a completely black color of 0 (zero) gradation, but may be a color of low gradation that appears black when viewed with the naked eye or appears dark gray.

Hereinafter, a method for securing the real-time sensing timing for each of the two screen switching section determination methods briefly described above will be described in more detail.

8 to 10 are diagrams for explaining a method for securing real-time sensing timing based on user triggering according to the present embodiments.

Referring to FIG. 8, according to the method for securing real-time sensing timing based on user triggering according to the present exemplary embodiments, the screen transition period (CT) determined by the screen transition period determination unit 710 may include a channel change Signal or a screen UI change signal.

The screen switching period CT determined in this manner is regarded as the sensing driving period ST, and the sensing driving can be proceeded under the control of the driving control unit 720. [

The section other than the screen switching section CT is the video driving section DT, and the video driving proceeds.

As described above, when a screen is switched to a screen that the user does not actually see or is not interested in, such as a black screen due to a user input for channel change, screen UI change, etc., The sensing operation can be performed while the power is on without any influence on the screen viewing of the user.

Referring to FIG. 10, the screen transition period determination unit 710 determines whether to switch screens based on a user input signal (S1010).

As a result of the determination, if it is determined that the screen switching is not to be performed, the drive control unit 720 advances the image driving operation (S1020).

As a result of the determination, if it is determined that the screen switching is to be performed, the driving control unit 720 proceeds sensing operation during the screen switching interval CT (S1030).

On the other hand, since the temporal length of the screen changeover section CT is short to proceed all the sensing operations for all the subpixels, the sensing drive must be performed for each of the plurality of screen changeover sections CT, It is possible to complete the sensing for all the subpixels that have been made.

The sensing data obtained through the sensing operation progressed every screen transition period CT is collected and if the result of the collection includes sensing data for all the subpixels, the compensation value calculation process for each subpixel can be performed.

In this regard, according to the method for securing the real-time sensing timing based on the user triggering according to the present embodiments, the memory unit 320 temporarily stores the sensing data obtained through the sensing operation progressed every screen transition period CT A temporary memory 910 and a main memory 920 in which sensing data for all the subpixels stored in the temporary memory 910 are collectively moved or copied and stored.

9 and 10, the temporary memory 910 temporarily stores the sensing data output from the sensing unit 310 by driving the sensing operation for each of the image driving periods CT (S1040).

The memory management unit 900 may be required to confirm whether the sensing data for all the subpixels is stored in the temporary memory 910 in order to move or copy the sensing data from the temporary memory 910 to the main memory 920. [

That is, the memory management unit 900 determines whether the sensing data for all the sub-pixels SP is stored in the temporary memory 910 (S1050).

If the memory management unit 900 determines that the sensing data for all the subpixels SP are stored in the temporary memory 910, the memory management unit 900 stores the sensing data for the mode subpixels SP stored in the temporary memory 910 as And stores it in the main memory 920 (S1060).

When the memory management unit 900 completes the movement or copying of the sensing data from the temporary memory 910 to the main memory 920, the compensation unit 330 reads out all the subpixels stored in the main memory 920 The compensation value for all the subpixels SP can be calculated based on the sensing data for the subpixels SP (S1070).

By using the memory management method described above, it is possible to effectively compensate the characteristic values of the driving transistors of all the subpixels arranged in the organic light emitting display panel 110 through sensing driving progressed every screen transition period CT.

Meanwhile, steps S1050 and S1060 may be performed after the power-off signal is generated.

In this case, after the power-on signal is generated and the OLED display 100 is turned on, the compensating unit 330 can be compensated by advancing the image using the compensation value calculated in step S1070.

Hereinafter, a method of securing real-time sensing timing based on user triggering and a real-time sensing driving method using the same will be described. In the following, a method of securing real-time sensing timing based on system triggering and a real-

11 to 15 are diagrams for explaining a method for securing real-time sensing timing based on system triggering according to the present embodiments.

Referring to FIGS. 11 and 12, according to the system triggering-based real-time sensing timing assurance method according to the present embodiments, the screen transition interval CT determined by the screen transition interval determination unit 710 includes And may be a sensing driving period ST determined according to timing information.

A real-time sensing timing period is defined by preset real-time sensing timing information.

This real-time sensing timing interval is made by alternating one or more image driving intervals DT and one or more screen switching intervals CT.

Each screen switching section CT corresponds to the sensing driving section ST.

On the other hand, the screen transition period CT corresponding to the sensing driving period ST has a temporal length of one or more frames.

In the example of Figs. 12 and 13, the screen switching section CT corresponding to the sensing driving section ST may have a temporal length of three frames.

Accordingly, in the real-time sensing timing period, the video driving period DT of one frame length and the sensing driving period ST of three frames of length are repeatedly performed.

Three frames in the screen switching section CT corresponding to the sensing driving section ST may correspond to a black frame.

According to this, normal image driving is performed for one frame length, and sensing is performed while a black screen is displayed for three frame lengths.

The driving control unit 720 controls the black frame to be driven by a predetermined number (three in the example of FIG. 13) during the screen switching period CT corresponding to the sensing driving period ST, So that the sensing drive for sensing the characteristic value of the transistor DRT can be controlled to proceed.

As described above, the screen switching period (CT) defined as the sensing driving interval (ST) is determined according to the real-time sensing timing information set in the sensing system, regardless of the user input, .

As described above, a predetermined number (three in the example of FIG. 13) of black frames is driven during the screen switching interval CT corresponding to the sensing driving interval ST, (Three in the example of Fig. 13) frames are displayed.

Referring to FIG. 13, the black screen of three frames displayed between the normal image screens should not be recognized by the user.

Therefore, during the screen transition period CT corresponding to the sensing driving period ST, the number of continuously driven black frames can be determined according to the driving frequency at which the user can not recognize the black screen.

Here, the driving frequency that can not recognize the black screen corresponds to the driving frequency (referred to as "RS driving frequency ", Fs) for image driving in the real-time sensing timing section, and may be a preset value.

The basic driving frequency Fn in a general section other than the real-time sensing timing section, that is, a section in which no sensing drive is performed, may be an integral multiple of the RS driving frequency Fs.

Therefore, the RS drive frequency Fs is a value obtained by dividing the basic drive frequency Fn by the integer n.

n is a value obtained by dividing the basic driving frequency Fn by the RS driving frequency Fs, and corresponds to an image frame period. That is, one frame is driven for every n frames.

Accordingly, n-1 corresponds to the number of black frames continuously driven during the screen switching period CT corresponding to the sensing driving period ST.

13, when the basic driving frequency Fn is 120 Hz and the RS driving frequency Fs is preset to 30 Hz, the integer n corresponding to the video frame period is 120 Hz / 30 Hz = 4, The number of consecutively driven black frames n-1 is 3 during the screen switching interval CT corresponding to the frame ST.

Accordingly, one image frame is driven for every four frames, and the sensing drive progresses while three black frames are driven.

That is, one image frame FR # 1 is image-driven, and the sensing drive progresses while three successive black frames FR # 2, FR # 3, and FR # 4 are driven. The sensing operation is progressed while one of the image frames FR # 5 is driven and the three black frames FR # 6, FR # 7 and FR # 8 are driven.

As described above, although the sensing operation is proceeded while the black screen is being displayed during the screen switching interval CT corresponding to the sensing driving interval ST, the number of black frames is set within a range in which the user can not recognize the black screen So that real-time sensing can be performed without user's inconvenience.

Referring to FIG. 14, the sensing operation is performed for each of the image driving periods CT, and the sensing unit 310 generates sensing data for the corresponding sub-pixel and stores the sensing data in the memory unit 320. FIG.

In this way, when sensing data for all the sub-pixels arranged in the organic light emitting display panel 110 is stored in the memory unit 320, the compensating unit 330 corrects all the sub- The compensation value for all subpixels SP can be calculated based on the sensing data for the pixels SP.

A method for securing real-time sensing timing based on system triggering and a real-time sensing method using the same will be briefly described with reference to FIG.

Referring to FIG. 15, when a real-time sensing timing interval according to real-time sensing timing information starts, real-time sensing starts (S1510).

Accordingly, the RS driving frequency Fs is determined according to the real-time sensing timing information (S1520).

At this time, the length (i.e., the number of frames) of each of the screen driving sections CT corresponding to the video driving section DT and the sensing driving section ST is determined. That is, the number (n-1) of black frames in the screen transmission interval CT corresponding to the sensing driving interval ST is determined.

When the RS driving frequency Fs is determined, the image frame and the black frame are alternately driven in accordance with the RS driving frequency Fs, and the sensing driving is performed in the black frame driving interval (S1530).

When the sensing data for all the subpixels is obtained in step S1530, the real-time sensing is terminated (S1540), and the image frame is driven according to the basic driving frequency Fn (S1550).

16 is a diagram showing a controller 140 for securing real-time sensing timing according to the present embodiments.

Referring to FIG. 16, the controller 140 for securing real-time sensing timing according to the present embodiment includes a screen switching section determining section 710 for determining a screen switching section CT, A driving control unit 720 for controlling sensing driving for sensing the characteristic value of the driving transistor DRT, and the like.

By using the controller 140 described above, the sensing drive can be performed every screen change interval CT before the power-off signal is generated, so that the sensing drive can be performed in real time during the video drive.

The screen change interval determining unit 710 can determine the screen change interval (CT) based on a channel change signal according to user input or a screen UI (User Interface) change signal.

According to the above description, when a screen is switched to a screen that the user does not actually see or is not interested in, such as a black screen due to user input for channel change, screen UI change, etc., The sensing operation can be performed while the power is on without any influence on the screen viewing of the user.

On the other hand, the screen change section determining section 710 may determine the sensing drive section ST determined according to the preset real time sensing timing information as the screen change section CT.

Accordingly, the driving control unit 720 can control the sensing driving to proceed while the predetermined number of black frames are continuously driven during the screen switching interval CT.

As described above, regardless of the user input, the screen switching section (CT) defined as the sensing driving interval (ST) is determined according to the real time sensing timing information set in the sensing system, and the sensing driving can be performed in real time have.

In addition, although the sensing operation is proceeded while the black screen is being displayed during the screen switching period CT corresponding to the sensing driving period ST, the number of black frames is adjusted within a range in which the user can not recognize the black screen, When driving is performed, real-time sensing can be performed without a black screen of the user.

17 to 19 are flowcharts illustrating a method of driving the organic light emitting display 100 for securing real-time sensing timing according to the present embodiments.

Referring to FIG. 17, the driving method of the OLED display 100 for securing the real-time sensing timing according to the present exemplary embodiments includes a step S1710 of driving a video image and a step S1710 of determining a screen switching period CT (Step S1720) and a sensing drive for sensing the characteristic value of the driving transistor DRT during a screen switching interval CT (step S1730).

According to the driving method described above, sensing driving can be performed every screen switching interval (CT) before a power-off signal is generated, so that sensing driving can be performed in real time during video driving.

18, in the case where the real-time sensing timing is ensured based on the user triggering, in the step S1720 of determining the screen switching interval CT, the channel change signal generated according to the user input or the screen UI (CT) can be determined according to an interface change signal.

According to this, when a user input for changing a channel or changing a screen UI occurs and the screen is switched to a screen that the user does not actually see or is not interested in, such as a black screen, By driving, the sensing operation can be performed while the power is on without affecting the user's viewing of the screen at all.

As shown in FIG. 19, in the case where the real-time sensing timing is secured based on the system triggering, in the step S1720 of determining the screen switching interval CT, the sensing driving period ST) can be determined as the screen switching section CT.

During the sensing operation, a predetermined number of black frames are successively driven and displayed within a range that the black screen of the user is not recognized.

According to this, the screen switching section (CT) defined as the sensing driving interval (ST) is determined according to the real-time sensing timing information set in the sensing system, and the sensing driving can be performed in real time during the video driving.

In addition, although the sensing operation is proceeded while the black screen is being displayed during the screen switching period CT corresponding to the sensing driving period ST, the number of black frames is adjusted within a range in which the user can not recognize the black screen, When driving is performed, real-time sensing can be performed without a black screen of the user.

According to the embodiments as described above, the controller 140 for real time sensing timing for sensing the characteristic value of the driving transistor during the image driving in real time and allowing the sensing driving to proceed at the secured real time sensing timing, The OLED display panel 110, the OLED display 100, and the driving method thereof.

In addition, according to the present exemplary embodiments, a period during which a screen is switched by user input during a video driving is determined as a sensing driving period to ensure real-time sensing timing, and a sensing driving timing can be secured in real time A controller 140, an organic light emitting display panel 110, an organic light emitting display 100, and a driving method thereof.

In addition, according to the embodiments, a screen switching period in which the screen is switched to the black screen as the sensing driving period during the video driving is determined to ensure the real-time sensing timing, and the sensing operation is performed while driving the black frame at the secured real- A controller 140, an organic light emitting display panel 110, an organic light emitting display device 100, and a method of driving the same may be provided.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. , Separation, substitution, and alteration of the invention will be apparent to those skilled in the art. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

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

Claims (16)

An organic light emitting display panel in which organic light emitting diodes and driving transistors are arranged for each subpixel;
A screen switching section determining section for determining a screen switching section;
A driving controller for controlling the sensing driving to sense the characteristic value of the driving transistor during the screen switching period;
A sensing unit sensing a voltage of a sensing line electrically connected to each sub-pixel during the screen switching period and generating sensing data based on the sensed voltage; And
And a compensation unit for calculating a compensation value based on the sensing data for each sub-pixel when the sensing data for all the sub-pixels is generated. The method according to claim 1,
The screen switching section,
And a channel change signal according to user input or a screen UI (User Interface) change signal. 3. The method of claim 2,
A temporary memory for storing the sensing data output from the sensing unit; And
If it is determined that the sensing data for all the subpixels are stored in the temporary memory, and if it is determined that the sensing data for all the subpixels are stored in the temporary memory, the sensing data for the mode subpixels stored in the temporary memory is stored in the main memory And a memory management unit for storing the management information,
Wherein the compensation unit comprises:
And calculates a compensation value for all subpixels based on sensing data for all subpixels stored in the main memory. The method according to claim 1,
The screen switching section,
And a sensing driving period determined according to preset real-time sensing timing information. 5. The method of claim 4,
The drive control unit may include:
During the screen transition period,
Controls a predetermined number of black frames to be driven,
And controls the sensing driving to sense the characteristic value of the driving transistor. 6. The method of claim 5,
During the screen switching period, the number of consecutively driven black frames,
The organic light emitting display according to claim 1, The method according to claim 1,
Wherein a characteristic value of the driving transistor is a threshold voltage. A screen switching section determining section for determining a screen switching section; And
And a driving controller for controlling sensing driving for sensing a characteristic value of the driving transistor during the screen switching period. 9. The method of claim 8,
The screen switching section determines,
Wherein the controller determines the screen switching period by a channel change signal according to user input or a screen UI (User Interface) change signal. 9. The method of claim 8,
The screen switching section determines,
And determines a sensing driving period determined according to preset real-time sensing timing information as the screen switching period. 11. The method of claim 10,
The drive control unit may include:
During the screen transition period,
And controls the sensing driving to proceed while a predetermined number of black frames are continuously driven. A method of driving an organic light emitting diode (OLED) display device including an organic light emitting diode (OLED) display panel in which an organic light emitting diode and a driving transistor are disposed for each subpixel,
Proceeding to image driving;
Determining a screen transition period; And
And driving the sensing driving for sensing a characteristic value of the driving transistor during the screen switching period. 13. The method of claim 12,
In the step of determining the screen switching period,
And determines the screen switching interval according to a channel change signal or a screen UI (User Interface) change signal generated according to a user input. 13. The method of claim 12,
In the step of determining the screen switching period,
And determining a sensing driving period determined according to preset real-time sensing timing information as the screen switching period. 15. The method of claim 14,
Wherein a predetermined number of black frames are continuously driven and displayed while the sensing driving is being performed. Organic light emitting diodes;
A driving transistor for driving the organic light emitting diode;
A sensing transistor connected between a first node of the driving transistor and a sensing line;
A switching transistor coupled between the second node of the driving transistor and the data line; And
And a storage capacitor coupled between a first node and a second node of the driving transistor,
Wherein the sensing line has a voltage rising at a reference voltage during a screen switching period.

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