KR20140076061A - Orglanic light emitting display device - Google Patents

Abstract

An organic light emitting display device according to the present invention which can improve the uniformity of an image by correcting the property change of the driving transistor of each pixel and reduce the capacity of a memory part which stores the property change of the driving transistor of each pixel includes a display panel which includes unit pixels consisting of sub pixels and includes a driving transistor where each sub pixel uses a data current based on a data voltage in order to allow an organic light emitting device to emit light; and a panel driving part which operates the display panel in a sensing mode and a display mode, senses the mobility and the threshold voltage of the driving transistor of each pixel in the sensing mode, stores a memory part by sampling only the sensing data corresponding to sampling pixels set in the display panel, and generates the data voltage by modulating input data based on the sensing data stored in the memory part.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic light emitting display device,

The present invention relates to an organic light emitting display.

Recently, with the development of multimedia, the importance of flat panel display devices is increasing. In response to this, flat panel display devices such as liquid crystal display devices, plasma display devices, and organic light emitting display devices have been commercialized. Among such flat panel display devices, organic light emitting display devices have attracted attention as a next generation flat panel display device because they have a high response speed, low power consumption, and self light emission, so that there is no problem in viewing angle.

A general organic light emitting display includes a display panel including a plurality of pixels and a panel driver for emitting each pixel. Here, each pixel is formed in a pixel region defined by the intersection of a plurality of data lines and a plurality of gate lines.

Each of these pixels includes a switching transistor Tsw, a driving transistor Tdr, a capacitor Cst, and an organic light emitting diode OLED, as shown in Fig.

The switching transistor Tsw is switched in accordance with the gate signal GS supplied to the gate line GL to supply the data voltage Vdata supplied to the data line DL to the driving transistor Tdr.

The driving transistor Tdr is switched according to the data voltage Vdata supplied from the switching transistor Tsw and controls the data current Ioled flowing to the organic light emitting element OLED by the driving voltage VDD.

The capacitor Cst is connected between the gate terminal and the source terminal of the driving transistor Tdr to store a voltage corresponding to the data voltage Vdata supplied to the gate terminal of the driving transistor Tdr, Tdr).

The organic light emitting diode OLED is electrically connected between the source terminal of the driving transistor Tdr and the cathode electrode to which the cathode voltage VSS is applied and emits light by the data current Ioled supplied from the driving transistor Tdr.

Each pixel of such a general organic light emitting display uses the switching of the driving transistor Tdr according to the data voltage Vdata to adjust the size of the data current Ioled flowing to the organic light emitting element OLED by the driving voltage VDD So that a predetermined image is displayed by causing the organic light emitting diode OLED to emit light.

However, in general organic light emitting display devices, there is a problem that the characteristics (for example, threshold voltage Vth / mobility) of the driving transistor Tdr are different depending on the driving transistor Tdr according to the non-uniformity of the manufacturing process of the thin film transistor A uniform image quality can not be realized due to the deviation of the current flowing through the organic light emitting diode OLED even when the same data voltage Vdata is applied to the driving transistor Tdr of each pixel in a general organic light emitting display device have.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an organic light emitting diode (OLED) display device capable of improving the uniformity of image quality by compensating a change in characteristics of driving transistors of each pixel.

It is another object of the present invention to provide an organic light emitting display device capable of reducing the capacity of a memory portion storing a change in a driving transistor characteristic of each pixel sensed in each pixel.

According to an aspect of the present invention, there is provided an organic light emitting display including a plurality of unit pixels each including a plurality of sub-pixels, A display panel including a driving transistor for driving the display panel; Wherein the sensing panel is operated in a sensing mode or a display mode, the threshold voltage and the mobility of the driving transistor of each sub-pixel are sensed in the sensing mode, and only the sensing data corresponding to the plurality of sampling pixels set on the display panel is sampled And a panel driver for modulating the input data based on the sensing data stored in the memory unit in the display mode to generate the data voltage in the memory unit.

The plurality of sampling pixels are each sub-pixel formed on an odd-numbered horizontal line or an even-numbered horizontal line of the display panel, or a sub-pixel of an odd-numbered or odd-numbered unit pixel based on a vertical direction of the display panel. do.

And the plurality of sampling pixels are sub-pixels of unit pixels arranged in a zigzag pattern on the display panel among the plurality of unit pixels.

Wherein the one unit pixel is composed of red, white, green, and blue sub-pixels, and the plurality of sampling pixels are red, white, green, and blue that are the same or different for each of the white sub- Green, and blue sub-pixels, respectively.

The panel driving unit senses the threshold voltage and the mobility of the driving transistor of each sub-pixel in the sensing mode to generate sensing data of each sub-pixel. In the display mode, the modulation data of each sub- A column driving unit for converting the driving signal; A sensing data processing unit for sampling sensing data corresponding to the plurality of sampling pixels among the sensing data of each sub pixel during the sensing mode and storing the sampled sensing data in the memory unit; And generating compensation data of each sub-pixel based on the sensing data stored in the memory unit in the display mode, modulating input data of each sub-pixel based on the generated compensation data, And a timing controller for generating modulation data and supplying the modulated data of each sub-pixel to the column driving unit.

The panel driving unit senses the threshold voltage and the mobility of the driving transistor of each sub-pixel in the sensing mode to generate sensing data of each sub-pixel. In the display mode, the modulation data of each sub- A column driving unit for converting the driving signal; The sensing unit may calculate luminance component sensing data and first and second color component sensing data of each unit pixel based on sensing data of each sub-pixel during the sensing mode, and output luminance component sensing data corresponding to the plurality of sampling pixels A sensing data processor for sampling the first and second color component sensing data and storing the sampled data in the memory; And generating compensation data for each of the sub pixels based on the luminance component sensing data and the first and second color component sensing data stored in the memory unit in the display mode, And a timing controller for modulating the input data of each sub-pixel to generate modulation data of each sub-pixel and supplying the modulated data of each sub-pixel to the column driver.

The sensing data processing unit samples only the luminance component sensing data of each unit pixel and stores the sampled data in the memory unit.

Wherein the timing control unit generates the luminance component and the first and second color components of each unit pixel based on the input data of each unit pixel and outputs the luminance component of each unit pixel based on the luminance component sensing data of each unit pixel stored in the memory unit Modulating the luminance component of the unit pixel and generating modulation data to be supplied to each sub-pixel based on the modulated luminance component of each unit pixel and the first and second color components of the unit pixel.

The sensing data processing unit samples luminance component sensing data of each unit pixel and stores the sampled luminance component sensing data in the memory unit and samples at least one color component sensing data among first and second color component sensing data corresponding to the plurality of sampling pixels And stores it in the memory unit.

Wherein the timing control unit generates the luminance component and the first and second color components of each unit pixel based on the input data of each unit pixel and outputs the luminance component of each unit pixel based on the luminance component sensing data of each unit pixel stored in the memory unit The first and second color components and at least one color component of each unit pixel based on at least one color component sensing data of the first and second color component sensing data stored in the memory unit, And generates modulation data to be supplied to the respective sub-pixels based on the modulated luminance components of the respective unit pixels and the first and second color components modulated.

According to the present invention, the characteristic change of the driving transistor sensed from each sub-pixel is reflected on the input data, so that the characteristic variation of the driving transistor included in each pixel can be compensated periodically or in real time to improve the luminance uniformity.

In addition, according to the present invention, a change in the characteristics of the driving transistor sensed from each sub-pixel is sampled and stored in the memory unit, thereby reducing the storage capacity of the memory unit, thereby reducing the cost of the memory unit.

FIG. 1 is a view for explaining a pixel structure of a general organic light emitting display device.
2 is a view for explaining an organic light emitting display according to an embodiment of the present invention.
3 is a view for explaining a configuration of an organic light emitting display according to an exemplary embodiment of the present invention.
4 is a circuit diagram for explaining the pixel structure shown in FIG.
5 is a view for explaining a column driving unit shown in FIG.
6 is a waveform diagram showing driving waveforms in the sensing mode of the organic light emitting diode display according to the embodiment of the present invention.
FIG. 7 is a diagram for explaining the first embodiment of the sensing data processing unit shown in FIG.
8 is a diagram for explaining a second embodiment of the sensing data processing unit shown in FIG.
9A to 9H are views showing various embodiments of the sampling sub-pixel set in the display panel for sampling the sensing data processing unit according to the first embodiment of the present invention shown in FIG.
FIGS. 10A to 10C are diagrams for explaining various sampling methods of the sensing data processing unit according to the second embodiment of the present invention shown in FIG.
11 is a view for explaining a memory unit and a timing controller according to the first embodiment of the present invention shown in FIG.
12 is a view for explaining a memory unit and a timing controller according to a second embodiment of the present invention shown in FIG.
FIG. 13 is a diagram for explaining a memory unit and a timing controller according to a third embodiment of the present invention shown in FIG. 3. Referring to FIG.
14 is a waveform diagram showing driving waveforms in a display mode of an OLED display according to an embodiment of the present invention.

The meaning of the terms described herein should be understood as follows.

The word " first, "" second," and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms.

It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It should be understood that the term "at least one" includes all possible combinations from one or more related items. For example, the meaning of "at least one of the first item, the second item and the third item" means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a view for explaining an organic light emitting display according to an embodiment of the present invention.

Referring to FIG. 2, the OLED display includes a display panel 110, a panel driver 120, and a memory unit 130.

The display panel 110 includes a plurality of subpixels P and the organic light emitting devices included in each of the plurality of subpixels P receive the data currents As shown in FIG. Here, each of the plurality of sub-pixels P may be any one of a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel. One unit pixel for displaying one image may include an adjacent red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel, or may include a red pixel, a green pixel, and a blue pixel. Hereinafter, it is assumed that one unit pixel is composed of a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel.

The panel driver 120 drives the display panel 110 in a display mode or a sensing mode. Here, the display mode means a mode in which a predetermined image is displayed by emitting an organic light emitting element included in each sub-pixel P according to input data, and the sensing mode is a mode in which a driving transistor And the mode of sensing the threshold voltage and mobility.

In the sensing mode, the panel driver 120 according to the first embodiment senses threshold voltages and mobilities of driving transistors included in each of the plurality of sampling sub-pixels P set in the display panel 110, The threshold voltage sensing data and the mobility sensing data corresponding to the threshold voltage and the mobility of the driving transistor of each sensing sub-pixel P are stored in the memory unit 130. That is, in the sensing mode, the panel driver 120 according to the first embodiment generates the sensing data voltage corresponding to the sensing data and drives each of the sampling sub-pixels P set in the display panel 110 The first and second sensing voltages corresponding to the threshold voltage and the mobility of the driving transistor of each sampling sub-pixel P are sensed, and the sensed first and second sensing voltages are analog- The threshold voltage sensing data and the mobility sensing data of the sub-pixel P are generated and stored in the memory unit 130.

In the display mode, the panel driving unit 120 according to the first embodiment generates sub-pixels corresponding to each sub-pixel based on the threshold voltage sensing data and the mobility sensing data of the sampling sub-pixels P stored in the memory unit 130, The compensation data of each sub-pixel P for compensating the threshold voltage and the mobility of the driving transistor included in the pixel P are calculated and the compensation data of each sub-pixel P is calculated in accordance with the calculated compensation data of the sub- P, and supplies the compensated input data to the respective sub-pixels P by converting the compensated input data into data voltages.

In the sensing mode, the panel driver 120 according to the second embodiment senses threshold voltages and mobilities of the driving transistors included in the respective subpixels P, and detects the threshold voltages and mobilities of the driving transistors included in the sensed subpixels P Based on the threshold voltage and the mobility of the driving transistor, the luminance component sensing data and the first and second color component sensing data of each unit pixel and supplies the luminance component sensing data of all the calculated unit pixels to the memory unit 130. [ And the first and second color component sensing data of the sampling unit pixels set in the display panel 110 are selectively sampled and stored in the memory unit 130. [ That is, in the sensing mode, the panel driver 120 according to the second embodiment generates a sensing data voltage corresponding to the sensing data and drives each of the sub-pixels P set in the display panel 110 Sensing the first and second sensing voltages corresponding to the threshold voltage and the mobility of the driving transistor of each sub-pixel P, and analog-to-digital converts the sensed first and second sensing voltages, The threshold voltage sensing data and the mobility sensing data of the subpixel P are generated and based on the threshold voltage sensing data and the mobility sensing data of each subpixel P, the red, green, blue, and white (Hereinafter referred to as "4-color data"), and calculates luminance component sensing data and first and second color component sensing data of each unit pixel on the basis of the four- And stores the luminance component sensing data of all the unit pixels in the memory unit 130 and selectively samples the first and second color component sensing data of the sampling unit pixel set in the display panel 110 and outputs the sampled data to the memory unit 130 .

In the display mode, the panel driver 120 according to the second embodiment calculates four-color speculative color data of each unit pixel using only the luminance component data of each unit pixel stored in the memory unit 130, First and second color component data of each unit pixel is calculated based on first and second color component data of each sampling unit pixel stored in the memory unit 130, and the first and second color component data Color estimated color data of each unit pixel by using the data and the luminance component data of the corresponding unit pixel stored in the memory unit 130. [ Then, the panel driver 120 according to the second embodiment determines the threshold voltage of the driving transistor included in each subpixel P based on the deviation between the four-color-estimated color data of each unit pixel and the sensing data Calculates the compensation data of each sub pixel P to compensate for the voltage and the movement, compensates the input data of each sub pixel P according to the calculated compensation data of each sub pixel P, And the input data is converted into a data voltage and supplied to each sub-pixel P. [

Since the OLED display according to the present invention does not store the sensing results of all the subpixels P formed on the display panel 110 using the sampling scheme in the memory unit 130, 130 can be reduced.

Hereinafter, the configuration of the organic light emitting diode display including the panel driver according to the first or second embodiment of the present invention described above with reference to FIGS. 3 to 14 will be described.

FIG. 3 is a view for explaining a configuration of an organic light emitting display according to an exemplary embodiment of the present invention, and FIG. 4 is a circuit diagram for explaining a pixel structure shown in FIG.

Referring to FIGS. 3 and 4, the OLED display includes a display panel 110, a panel driver 120, and a memory 130, as described above.

The display panel 110 includes a plurality of sub-pixels P. The plurality of sub-pixels P may include a plurality of gate line groups GL1 to GLm, a plurality of data lines DL1 to DLn, and a plurality of sensing lines GL1 to GLn arranged in parallel with the plurality of data lines DL1 to DLn, (SL1 to SLn).

Each of the plurality of gate line groups GL1 to GLm is formed in a line along a first direction of the display panel 110, for example, a horizontal direction. At this time, each of the plurality of gate line groups GL1 to GLm includes first and second gate lines GLa and GLb adjacent to each other. The first and second gate signals GSa and GSb are individually supplied from the panel driver 120 to the first and second gate lines GLa and GLb of the gate line groups GL1 to GLm.

Each of the plurality of data lines DL1 to DLn is formed to be parallel to the second direction of the display panel 110, for example, the longitudinal direction so as to intersect each of the plurality of gate line groups GL1 to GLm. The data voltage Vdata is separately supplied from the panel driver 120 to each of the data lines DL1 to DLn. At this time, a data voltage Vdata compensated for the threshold voltage and the mobility of the driving transistor Tdr included in the corresponding subpixel P is supplied to each of the plurality of data lines DL1 to DLn.

Each of the plurality of sensing lines SL1 to SLn is formed in parallel with each of the plurality of data lines DL1 to DLn. The reference voltage Vref or the precharging voltage Vpre is selectively supplied to the sensing lines SL1 to SLn from the panel driver 120. [ That is, the reference voltage Vref is selectively supplied to the sensing lines SL1 to SLn in the display mode, and the precharging voltage Vpre is selectively supplied to the sensing lines SL1 to SLn in the sensing mode.

A plurality of driving voltage lines PLi are formed on the display panel 110 in parallel with the plurality of data lines DL1 to DLn. Each of the plurality of driving voltage lines PLi is supplied with a driving voltage VDD from a voltage supply unit (not shown) of the panel driving unit 120.

Each of the plurality of sub-pixels P includes a pixel circuit PC and an organic light emitting diode (OLED). Each of the plurality of sub-pixels P may be any one of a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel. One unit pixel for displaying one image is composed of an adjacent red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel.

The pixel circuit PC may include a first switching transistor Tsw1, a second switching transistor Tsw2, a driving transistor Tdr, and a capacitor Cst. Here, the transistors Tsw1, Tsw2, and Tdr may be an a-Si TFT, a poly-Si TFT, an oxide TFT, an organic TFT, or the like as an N-type thin film transistor (TFT).

The first switching transistor Tsw1 includes a gate electrode connected to the first gate line GLa of the gate line group GLi, a first electrode connected to the adjacent data line DLi, and a gate electrode connected to the gate of the driving transistor Tdr And a second electrode connected to a first node n1 which is an electrode. The first switching transistor Tsw1 may receive the data voltage Vdata supplied to the data line DLi according to the first gate signal GSa of the gate-on voltage level supplied to the first gate line GLa To the gate electrode of the first node n1, that is, the driving transistor Tdr.

The second switching transistor Tsw2 includes a gate electrode connected to the second gate line GLb of the gate line group GLi, a first electrode connected to the adjacent sensing line SLi, and a source of the driving transistor Tdr And a second electrode connected to a second node n2 which is an electrode. The second switching transistor Tsw2 is connected to the reference voltage Vref supplied to the sensing line SLi according to the second gate signal GSb of the gate-on voltage level supplied to the second gate line GLb The precharging voltage Vpre) to the second node n2, that is, the source electrode of the driving transistor Tdr.

The capacitor Cst includes first and second electrodes connected between the gate electrode and the source electrode of the driving transistor Tdr, that is, the first and second nodes n1 and n2. The capacitor Cst charges the difference voltage between the voltages supplied to the first and second nodes n1 and n2, and then switches the driving transistor Tdr according to the charged voltage.

The driving transistor Tdr includes a gate electrode commonly connected to the second electrode of the first switching transistor Tsw1 and the first electrode of the capacitor Cst, a first electrode of the second switching transistor Tsw2, and a capacitor Cst A source electrode commonly connected to the organic light emitting device OLED, and a drain electrode connected to the driving voltage line PLi. This driving transistor Tdr controls the amount of current flowing from the driving voltage line PLi to the organic light emitting element OLED by being turned on by the voltage of the capacitor Cst.

In the above-described embodiment, the pixel circuit PC is composed of three transistors and one capacitor. However, the number of transistors and capacitors constituting the pixel circuit PC may be variously modified.

The organic light emitting diode OLED emits a monochromatic light having a luminance corresponding to the data current Ioled by the data current Ioled supplied from the pixel circuit PC, i.e., the driving transistor Tdr. The organic light emitting device OLED includes an anode electrode (not shown) connected to the second node n2 of the pixel circuit PC, an organic layer (not shown) formed on the anode electrode, and a cathode electrode (CE). At this time, the organic layer may have a structure of a hole transporting layer / an organic light emitting layer / an electron transporting layer or a structure of a hole injecting layer / a hole transporting layer / an organic light emitting layer / an electron transporting layer / an electron injecting layer. Further, the organic layer may further include a functional layer for improving the luminous efficiency and / or lifetime of the organic light emitting layer. The cathode electrode CE may be formed individually in each of the plurality of pixels P or may be formed so as to be connected to a plurality of pixels P in common.

The panel driver 120 drives the display panel 110 in a sensing mode or a display mode. In the sensing mode, the panel driver 120 senses the threshold voltage and the mobility of the driving transistor included in the sampling sub-pixel P set on the display panel 110 through each of the plurality of sensing lines SL1 to SLn , And stores the sensed sensing data in the memory unit 130. In the display mode, the panel driver 120 corrects the input data based on the sensing data stored in the memory unit 130, and outputs the organic light emitting elements included in each sub-pixel P And displays a predetermined image. The panel driver 120 includes a row driver 122, a column driver 124, a sensing data processor 126, and a timing controller 128.

The row driver 122 is connected to a plurality of gate line groups GL1 to GLm and operates in a display mode or a sensing mode under the control of the timing controller 128. [

In the display mode, the row driver 122 generates the first and second gate signals GSa and GSb of the gate-on voltage level for each horizontal period and sequentially outputs the first and second gate signals GSa and GSb to the gate line groups GL1 to GLm Supply. At this time, each of the first and second gate signals GSa and GSb has a gate-on voltage level during a data charging period of each sub-pixel P, and a gate-off voltage level during a light- .

In the sensing mode, the row driver 122 drives the first and second gate signals corresponding to the initialization period, the voltage charging period, and the voltage sensing period of the subpixels P included in the horizontal line to be sensed GSa, and GSb and supplies them to the corresponding gate line group GLi.

The row driver 122 may be formed in the form of an integrated circuit or may be formed directly on the substrate of the display panel 110 together with the transistor forming process of each sub pixel P, m gate line groups GL1 to GLm, respectively.

The column driver 124 is connected to a plurality of data lines DL1 to DLn and a plurality of sensing lines SL1 to SLn and operates in a display mode and a sensing mode under the control of the timing controller 210. [

In the display mode, the column driver 124 supplies the reference voltage Vref to the plurality of sensing lines SL1 to SLn during a data charging period of each sub-pixel P in units of one horizontal period And simultaneously supplies the correction data R '/ W' / G '/ B' supplied from the timing control unit 128 to the data lines DL1 to DLn by converting the data to the data voltages Vdata.

In the sensing mode, the column driver 124 senses threshold voltages and mobilities of the driving transistors included in the respective sub-pixels P formed on the display panel 110, The threshold voltage sensing data S_Vth and the mobility sensing data S_k corresponding to the threshold voltage and the mobility of the driving transistor of the pixel P are generated and supplied to the sensing data processing unit 126. [

The sensing data processing unit 126 operates only in the sensing mode and controls the threshold voltage sensing data S_Vth and the mobility sensing data S_k supplied from the column driver 124 to a predetermined sampling scheme And stores the data in the memory unit 130. [

The sensing data processing unit 126 according to the first embodiment is configured to compare the threshold voltage sensing data S_Vth of each subpixel P supplied from the column driver 124 according to the first embodiment with the mobility Only the threshold voltage sensing data S_Vth and the mobility sensing data S_k of each of the plurality of sampling sub-pixels P set in the sensing data S_k are sampled and stored in the memory unit 130. The threshold voltage sensing data S_Vth for the driving transistor Tdr of the plurality of sampling sub-pixels P set in the display panel 110 and the mobility Only the sensing data S_k is stored.

The sensing data processing unit 126 according to the second embodiment is configured to compare the threshold voltage sensing data S_Vth of each subpixel P supplied from the column driver 124 according to the second embodiment with the mobility The luminance component sensing data S_Y and the first and second color component sensing data S_Cb and S_Cr of each unit pixel are calculated on the basis of the sensing data S_k and the luminance component sensing data S_Y of each unit pixel, Or the first and second color component sensing data S_Cb and S_Cr of the plurality of sampling unit pixels set together with the luminance component sensing data S_Y of each unit pixel, 130). Accordingly, only the luminance component sensing data S_Y of all the unit pixels of the display panel 110 is stored in the memory unit 130 according to the second embodiment, or the luminance component sensing data S_Y of all the unit pixels and a plurality of Only the first and second color component sensing data (S_Cb, S_Cr) of the sampling unit pixel are stored.

The timing controller 128 operates the row driving unit 122, the column driving unit 126 and the sensing data processing unit 128 in the display mode or the sensing mode.

In the display mode, the timing controller 128 drives each subpixel P connected to each of the gate line groups G1 to Gm in one horizontal period as a data charging period and a light emitting period. The timing control unit 128 controls the timing of the data control signal DCS corresponding to the display mode based on a timing synchronization signal TSS input from an external system body (not shown) or a graphic card (not shown) And controls the driving timings of the row driving unit 122 and the column driving unit 126 in the display mode using the generated gate control signal GCS.

The sensing mode may be performed before shipment of the organic light emitting display device, at the initial driving time of the display panel 110, after the long time driving of the display panel 110, or at the re-driving time after the long time. In this sensing mode, the threshold voltage / mobility of the driving transistor Tdr of each subpixel P formed on one horizontal line is sensed for each blank period of the vertical synchronizing signal.

In the sensing mode, the timing controller 128 drives each subpixel P included in the horizontal line during the blanking period of the vertical synchronizing signal in the initialization period, the sensing voltage charging period, and the voltage sensing period. For this, the timing controller 128 controls the timing of the data control signal DCS corresponding to the sensing mode based on the timing synchronization signal TSS input from an external system body (not shown) or a graphic card (not shown) And controls the driving timing of each of the row driving unit 122 and the column driving unit 126 in the sensing mode using the generated gate control signal GCS.

The timing synchronization signal TSS may be a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE, a clock DCLK, or the like. The gate control signal GCS may include a gate start signal and a plurality of clock signals. The data control signal DCS may be a data start signal, a data shift signal, a data output signal, or the like.

In the display mode, the timing controller 128 according to the first embodiment controls the timing of the sub-pixel (s) based on the sensing data (S_Vth / S_k) stored in the memory 130 according to the first embodiment by the sensing mode, (R / W / G / B) to be supplied to each sub-pixel P according to the calculated compensation data and supplies the modulated data to the column driver 124, . The compensation data has a gradation value reflecting a compensation value for compensating a threshold voltage Vth of the driving transistor Tdr of each sub-pixel P and a characteristic change with respect to the mobility k. Specifically, the timing controller 128 according to the first embodiment outputs the threshold voltage sensing data (S_Vth) and the mobility sensing data (S_k) of the sampling unit pixel stored in the memory unit 130 to the sampling unit pixel The compensation data for the remaining unit pixels that have not been sensed are calculated based on the compensation data of the calculated sampling unit pixels. At this time, the timing controller 128 according to the first embodiment linearly interpolates the compensation data of the adjacent sampling unit pixels to calculate compensation data of the remaining unsensed pixels, It is possible to calculate the compensation data of the remaining unit pixels which are not sensed.

In the display mode, the timing controller 128 according to the second embodiment generates the sensing data (S_Y / S_Cb / S_Cr) stored in the memory unit 130 according to the first embodiment by the sensing mode W / G / B) to be supplied to each sub-pixel P according to the calculated compensation data and supplies the modulated data to the column driver 124. Specifically, the timing controller 128 according to the second embodiment calculates the compensation data for each sub-pixel of each unit pixel based on the luminance component sensing data (S_Y) of each unit pixel stored in the memory unit 130 Or based on the luminance component sensing data S_Y of each unit pixel stored in the memory unit 130 and the first and second color component sensing data S_Cb and S_Cr of the plurality of sampling unit pixels, And calculates compensation data for each of the sub-pixels of the unit pixel. At this time, the timing controller 128 according to the second embodiment linearly interpolates the first and second color component sensing data (S_Cb, S_Cr) of adjacent sampling unit pixels to generate first and second color component data Or the first and second color component data of the remaining unit pixels which are not sensed according to the average value of the first and second color component sensing data (S_Cb, S_Cr) of adjacent sampling unit pixels.

3, the column driver 124 is connected to one side of the plurality of data lines DL1 to DLn. However, the present invention is not limited thereto. In order to minimize the voltage drop of the data voltage Vdata And may be connected to both sides of each of the plurality of data lines DL1 to DLn. Similarly, the row driver 122 may be connected to both sides of each of the plurality of gate line groups GL1 to GLm in order to minimize the voltage drop of the gate signal.

5 is a view for explaining a column driving unit shown in FIG.

Referring to FIG. 5 with reference to FIG. 3, the column driver 124 includes a data voltage generator 124a, a switch 124b, and a sensing data generator 124c.

The data voltage generator 124a converts the correction data R '/ W' / G '/ B' supplied from the timing controller 128 into a data voltage Vdata in a display mode and outputs the data voltage to the data line DLi. . The data voltage generator 124a converts the sensing data supplied from the timing controller 128 into a sensing data voltage Vdata in a sensing mode and supplies the sensing data voltage to the data line DLi. To this end, the data voltage generator 124a includes a shift register for generating a sampling signal based on a data start signal and a data shift signal, a latch for latching data supplied from the timing controller 128, A gradation voltage generation section for generating a plurality of gradation voltages using a plurality of reference gamma voltages, a digital-analog conversion circuit for selecting and outputting a gradation voltage corresponding to data latched in the plurality of gradation voltages as a data voltage (Vdata) And an output unit for outputting the data voltage Vdata according to a data output signal.

The switching unit 124b supplies the reference voltage Vref to the sensing line SLi under the control of the timing control unit 128 in the display mode and supplies the reference voltage Vref to the sensing line SLi in the sensing mode, The voltage Vpre is supplied to the sensing line SLi and then the sensing line SLi is floated and then the sensing line SLi is connected to the sensing data generating unit 124c. For example, the switching unit 124b may be a demultiplexer.

When the sensing unit 124c is connected to the sensing line SLi by switching the switching unit 124b in the sensing mode, the sensing data generating unit 124c senses the voltage charged in the sensing line SLi, Generates corresponding sensing data (S_Vth, S_k) in digital form, and provides the generated sensing data (S_Vth, S_k) to the sensing data processing unit 126 described above.

6 is a waveform diagram showing driving waveforms in the sensing mode of the organic light emitting diode display according to the embodiment of the present invention.

The operation of the sensing mode for the sub-pixel P will be described with reference to FIGS. 3 to 6. FIG.

First, in the sensing mode, the timing controller 128 controls the driving timings of the row driver 122 and the column driver 124 to drive the sub-pixel P in the initialization period t1), the voltage charging period (t2), and the voltage sensing period (t3).

The first and second gate signals GSa and GSb of the gate-on voltage level are applied to the first and second gate lines GLa and GLb by the row driver 122 in the initialization period t1. And the sensing data voltage Vdata is supplied to the data line DLi and the precharging voltage Vpre is applied to the sensing line SLi by the column driver 124 . Thus, each of the first and second switching transistors Tsw1 and Tsw2 of the sub-pixel P is turned on by the first and second gate signals GSa and GSb of the gate-on voltage level, The data voltage Vdata is supplied to the first node n1 and the voltage of the second node n2 is initialized to the precharging voltage Vpre so that the data voltage Vdata and the pre- The differential voltage Vdata-Vpre of the voltage Vpre is charged.

In the voltage charging period t2, the first and second gate signals GSa and GSb of the gate-on voltage level are applied to the first and second gate lines GLa and GLb according to the row driver 122, And the sensing data line Vdata is continuously supplied to the data line DLi by driving the column driver 124 and the sensing line SLi is floated. Accordingly, in the voltage charging period t2, the driving transistor Tdr is turned on by the sensing data voltage Vdata, and the voltage corresponding to the current flowing in the driving transistor Tdr, which is turned on, Of the sensing line SLi. At this time, a voltage corresponding to the threshold voltage Vth of the driving transistor Tdr is charged in the sensing line SLi.

In the voltage sensing period t3, the first gate signal GSa of the gate-off voltage level is supplied to the first gate line GLa by the row driver 122, and at the same time, the gate- And the floating sensing line SLi is connected to the column driver 124 again. The second gate signal GSb of the second gate line GLb is supplied to the second gate line GLb. Accordingly, during the voltage sensing period t3, the column driver 124 detects the voltage charged in the connected sensing line SLi and supplies the detected voltage, that is, the threshold voltage of the driving transistor Tdr And supplies the voltage to the sensing data processing unit 126. The sensing data processing unit 126 generates the threshold voltage sensing data S_Vth.

The timing controller 128 senses the threshold voltage Vth of the driving transistor Tdr of each subpixel P through the sensing mode as described above and outputs the driving transistor Tdr of each subpixel P, The sensing mode for detecting the mobility (k) In this case, the timing controller 128 performs the same sensing mode as described above, except that the first switching transistor Tsw1 of the subpixel P is turned on only during the initialization period t1, And controls the driving of the row driving unit 122 and the driving of the column driving unit 124 so that the driving voltage Vdata is supplied only during the initialization period t1. Accordingly, when the sensing mode is resumed, the gate-source voltage of the driving transistor Tdr is increased due to the turn-off of the first switching transistor Tsw1 during the voltage charging period t2, The gate-source voltage of the driving transistor Tdr is held by the voltage and the voltage corresponding to the current flowing through the driving transistor Tdr, that is, the voltage corresponding to the mobility k of the driving transistor Tdr, (SLi). When the sensing mode is resumed, the column driver 124 detects the voltage charged in the sensing line SLi, that is, the voltage corresponding to the mobility k of the driving transistor Tdr, Converts the voltage into mobility sensing data (S_k) and provides it to the sensing data processing unit (126).

FIG. 7 is a diagram for explaining the first embodiment of the sensing data processing unit shown in FIG.

Referring to FIG. 7, the sensing data processing unit 126 according to the first embodiment may compare the threshold voltage sensing data S_Vth of each subpixel P supplied from the column driver 124 with the threshold voltage sensing data Only the threshold voltage sensing data S_Vth and the mobility sensing data S_k of each of the plurality of sampling sub-pixels P set in the mobility sensing data S_k are sampled and stored in the memory unit 130. To this end, the sensing data processing unit 126 according to the first embodiment includes a sampling unit 210 and a sensing data output unit 230.

The sampling unit 210 receives the threshold voltage sensing data S_Vth and the mobility sensing data S_k from the column driving unit 124 and outputs the sampled sub- P) and the mobility sensing data (S_k) and supplies the sampled data to the sensing data output unit (230). The plurality of sampling sub-pixels P are set to reduce the storage capacity of the memory unit 130, which will be described later.

The sensing data output unit 230 outputs the threshold voltage sensing data S_Vth and the mobility sensing data S_k of each of the plurality of sampling sub-pixels P sampled by the sampling unit 210 to the memory (130).

The sensing data processing unit 126 according to the first embodiment of the present invention may be configured to compare the threshold voltage sensing data S_Vth of the driving transistor of each subpixel P sensed by the column driving unit 124 with the threshold voltage Only the threshold voltage sensing data S_Vth and the mobility sensing data S_k corresponding to a plurality of sampling sub-pixels P set in the sensing data S_k are sampled and stored in the memory unit 130, 130).

8 is a diagram for explaining a second embodiment of the sensing data processing unit shown in FIG.

Referring to FIG. 8, the sensing data processing unit 126 according to the second embodiment may compare the threshold voltage sensing data S_Vth of each subpixel P supplied from the column driver 124 with the threshold voltage sensing data (S_Y) and first and second color component sensing data (S_Cb, S_Cr) of each unit pixel based on the mobility sensing data (S_k), and calculates the luminance component sensing data The first and second color component sensing data S_Cb and S_Cr of the plurality of sampling unit pixels set together with the luminance component sensing data S_Y of each unit pixel are sampled by storing the color component sensing data S_Y in the memory unit 130 And stores it in the memory unit 130. To this end, the sensing data processing unit 126 according to the second embodiment includes a color data generation unit 250, a luminance / color component data calculation unit 260, a sampling unit 270, and a sensing data output unit 280 do.

The color data generation unit 250 generates guess color data of each sub pixel P based on the threshold voltage sensing data S_Vth of each sub pixel P and the mobility sensing data S_k. For example, the color data generation unit 250 can generate guess color data of each sub pixel P based on the current Id flowing through the driving transistor Tdr as shown in the following equation (1) have.

Vgs represents a voltage difference between the gate voltage Vg of the driving transistor and the source voltage Vs, and Vgs represents a voltage difference between the gate voltage Vg and the source voltage Vs of the driving transistor. In this case, Id represents the current flowing through the driving transistor, k represents a proportional constant, And Vth represents the threshold voltage of the driving transistor to be sensed.

In Equation (1), the proportional constant k is a ratio of the mobility of the sensed driving transistor, the ratio of the channel width W to the channel length L of the driving transistor, and the ratio W / L of the insulating film Can be determined by the capacitance (C _OX ).

Among the variables of Equation (1), Vth and k are values sensed by the sensing mode, and Vg is a data voltage corresponding to the sensing data. Therefore, the color data generation unit 250 generates the current Id flowing through the driving transistor of the corresponding pixel based on the sensed threshold voltage sensing data S_Vth, the mobility sensing data S_k, and the data voltage of the sensing data ), And calculates a data gray scale value corresponding to the calculated current using a look-up table which is measured experimentally and has a data gray scale value according to the current, and calculates guess color data of each sub-pixel (P).

Then, the color data generation unit 250 calculates three color inferred data (C_R, C_G, C_B) of red, green, and blue for each unit pixel based on the estimated color data, And supplies the three color estimated color data C_R, C_G, and C_B of red, green, and blue to the luminance / color component data generation unit 260. For example, the color data generator 250 may add speculative data of the white subpixel P to the red speculative data C_R, the green speculative data C_G, and the blue speculative data C_B, It is possible to calculate three color speculative data C_R, C_G, and C_B of red, green, and blue for a unit pixel.

The luminance / color component data calculation unit 260 calculates the luminance / color component data for each unit pixel provided from the color data generation unit 250 based on three color inferred data (C_R, C_G, C_B) of red, The luminance component sensing data S_Y, and the first and second color component sensing data S_Cr and S_Cb are calculated. For example, the luminance / color component data calculator 250 calculates the luminance component data S_Y, the first and second color component data S_Cr and S_Cb ) Can be calculated.

The sampling unit 260 according to the first embodiment may store the luminance component sensing data S_Y, the first and second color component sensing data S_Cr and S_Cb for each unit pixel supplied from the luminance / color component data calculator 250, Only the luminance component sensing data S_Y of each unit pixel and supplies the sampled data to the sensing data output unit 270. [ Accordingly, the sensing data output unit 270 receives only the luminance component sensing data (S_Y) of each unit pixel sampled by the sampling unit 260, and stores the supplied sensing data in the memory unit 130.

The sampling unit 260 according to the second embodiment may store the luminance component sensing data S_Y for each unit pixel and the luminance component sensing data S_Y for each unit pixel in the first and second color component sensing data S_Cr and S_Cb, And at least one color component sensing data of the first and second color component sensing data S_Cr and S_Cb corresponding to a plurality of sampling unit pixels set on the display panel 110 and outputs the sampled color component sensing data to the sensing data output unit 270, . Accordingly, the sensing data output unit 270 outputs the sensing data S_Y of the unit pixels sampled by the sampling unit 260 and at least one of the first and second color component sensing data S_Cr and S_Cb And stores the received color component sensing data in the memory unit 130.

The sensing data processing unit 126 according to the second embodiment of the present invention is configured to compare the threshold voltage sensing data S_Vth of the driving transistor of each subpixel P sensed by the column driving unit 124 with the threshold voltage The luminance component sensing data S_Y and the first and second color component sensing data S_Cr and S_Cb of each unit pixel are calculated based on the sensing data S_k and the luminance component sensing data S_Y and at least one of the first and second color component sensing data S_Cr and S_Cb corresponding to the set plurality of sampling unit pixels is stored in the memory unit 130 to reduce the storage capacity of the memory unit 130 .

9A to 9H are views showing various embodiments of the sampling sub-pixel set in the display panel for sampling the sensing data processing unit according to the first embodiment of the present invention shown in FIG.

9A, the sampling sub-pixel according to the first embodiment includes sub-pixels R, W, and H formed in the odd-numbered horizontal lines HL1, HL3, and HL5 among the horizontal lines formed in the display panel 110, G, B). Of course, the sampling sub-pixel according to the first embodiment is set to each of the sub-pixels R, W, G, and B formed on the even-numbered horizontal lines HL2 and HL4 among the horizontal lines formed on the display panel 110 . In this case, in the sensing mode described above, it is possible not to sense the characteristic change of the driving transistor of each sub-pixel included in the horizontal line which is not set as the sampling sub-pixel.

9B, the sampling sub-pixels according to the second embodiment are arranged in the sub-pixels R, W, G and B of the odd-numbered unit pixels UP on the basis of the vertical line direction of the display panel 110 Lt; / RTI > Of course, the sampling sub-pixel according to the second embodiment may be set to each sub-pixel R, W, G, B of the odd-numbered unit pixels UP based on the vertical line direction of the display panel 110 .

9C, the sampling sub-pixel according to the third exemplary embodiment includes unit pixels UP arranged in a zigzag pattern along the vertical and horizontal line directions of the unit pixels UP formed in the display panel 110, And may be set to each of the sub-pixels R, W, G, and B.

9D, the sampling sub-pixel according to the third embodiment has red, green, and blue sub-pixels R, G, and B in each unit pixel UP with reference to the vertical line direction of the display panel 110. [ (R, G, B) and a white sub-pixel (W) among the sub-pixels (R, G, B) At this time, the sub-pixels R, G, and B of the red, green, and blue sub-pixels R, G, and B in each unit pixel UP are positioned with respect to the horizontal line direction of the display panel 110 , The red sub-pixel R, the green sub-pixel G, the green sub-pixel G, and the blue sub-pixel B in that order. For example, in the first to fourth unit pixels of each horizontal line, the sampling pixels set in the first unit pixel UP1 are red and white sub-pixels R and W, the second and third unit pixels UP, UP2 and UP3 may be the white and green sub-pixels W and G and the sampling pixels set to the fourth unit pixel UP4 may be the white and blue sub-pixels W and B. In this sampling sub-pixel according to the third embodiment, the luminance of the unit pixel is higher than the luminance of the red and blue sub-pixels R and B by the luminance of the white and green sub-pixels W and G It is set as described above because it is affected.

As shown in FIG. 9E, the sampling sub-pixel according to the fourth embodiment is the same as the sampling pixel according to the third embodiment described above, and includes a red sub-pixel R, a green sub-pixel G, The sub-pixel B, and the green sub-pixel G in this order. For example, in the first to fourth unit pixels of each horizontal line, the sampling pixels set in the first unit pixel UP1 are red and white sub-pixels R and W, the second unit pixels UP2, The sampling pixels set in the white and green sub pixels W and G and the third unit pixel UP3 are the white pixels and the blue sub pixels W and B and the fourth unit pixels UP4, May be white and green sub-pixels (W, G).

9F, the sampling sub-pixel according to the fifth embodiment may be set to the white and green sub-pixels W and G of each unit pixel UP formed on the display panel 110. [

In the case of sensing only the sampling sub-pixels according to the first to fifth embodiments, the present invention can reduce the storage capacity of the memory unit 130 by 50% as compared with the case of sensing all the sub-pixels of the display panel 110, .

As shown in FIG. 9G, the sampling sub-pixel according to the sixth embodiment is set to three sub-pixels for each unit pixel UP, and the three sub-pixels set for each unit pixel UP at this time are the odd- Lines HL1, HL3, HL5 and the even-numbered horizontal lines HL2, HL4. For example, the sampling pixels set in each unit pixel UP of the odd-numbered horizontal lines HL1, HL3 and HL5 may be red, white and green sub-pixels R, W and G, Green, and blue subpixels W, G, and B may be used as the sampling pixels set in the unit pixels UP of the first horizontal lines HL2 and HL4. In this case, the present invention can reduce the storage capacity of the memory unit 130 by 25% as compared with the case of sensing all the sub-pixels of the display panel 110.

As shown in FIG. 9H, the sampling sub-pixel according to the seventh embodiment is set to five sub-pixels for each sampling group SG consisting of two unit pixels UP adjacent vertically, The five sub-pixels set in the sampling groups SG1 and SG2 are set differently for the sampling groups SG1 and SG2. For example, the sampling pixel set in the first sampling group SG1 may include one red subpixel R, two white subpixels W, and one red subpixel Rp, among the subpixels of the two unit pixels UP adjacent vertically. The sampling pixel set in the second sampling group SG2 may be two green sub-pixels G among the sub-pixels of the two unit pixels UP adjacent up and down, Two green sub-pixels G, and one blue sub-pixel B, for example. In this case, the present invention can reduce the storage capacity of the memory unit 130 by 37.5% as compared with the case where all the sub-pixels of the display panel 110 are sensed.

FIGS. 10A to 10C are diagrams for explaining various sampling methods of the sensing data processing unit according to the second embodiment of the present invention shown in FIG.

8 and 10A, a first sampling method of the sensing data processing unit 126 according to the second embodiment of the present invention includes a step of generating luminance component sensing data S_Y, first color component sensing data S_Cr, Only the luminance component sensing data S_Y of each unit pixel can be sampled from the second color component sensing data S_Cb (for example, a red chrominance component) and the second color component sensing data S_Cb (for example, a blue chrominance component). The first sampling method can reduce the storage capacity of the memory unit 130 by 75% as compared with the case of sensing all the sub-pixels of the display panel 110. [

8 and 10B, a second sampling method of the sensing data processing unit 126 according to the second exemplary embodiment of the present invention includes a step of generating first color component sensing data S_Cr ) Or the second color component sensing data (S_Cb). For example, the second sampling method samples the luminance component sensing data S_Y and the first color component sensing data S_Cr of the odd-numbered unit pixels UP1 based on the vertical line direction of the display panel 110, The luminance component sensing data S_Y and the second color component sensing data S_Cb of the odd unit pixels UP2 can be sampled. The second sampling method can reduce the storage capacity of the memory unit 130 by 50% as compared with the case of sensing all the sub-pixels of the display panel 110. [

8 and 10C, a third sampling method of the sensing data processing unit 126 according to the second embodiment of the present invention is a method of sampling the odd-numbered horizontal lines HL1, HL3, and HL5 every odd- Sampling only the second color component sensing data S_Cb together with the luminance component sensing data S_Y and sampling only the luminance component sensing data S_Y for each odd unit pixel UP2 of the odd-numbered horizontal lines HL1, HL3 and HL5 And only the luminance component sensing data S_Y is sampled for each odd-numbered unit pixel UP1 of the even-numbered horizontal lines HL2 and HL4, It is possible to sample only the first color component sensing data S_Cr together with the component sensing data S_Y. Such a third sampling method can reduce the storage capacity of the memory unit 130 by 62.5% as compared with the case of sensing all the sub-pixels of the display panel 110. [

11 is a view for explaining a memory unit and a timing controller according to the first embodiment of the present invention shown in FIG.

Referring to FIG. 11 with reference to FIG. 3, the memory unit 130 according to the first embodiment includes first to third memories M1, M2, and M3.

In the first memory M1, the threshold voltage sensing data S_Vth and the mobility sensing data S_kh for each of the plurality of sampling sub-pixels sampled by the sensing mode, ) Are stored. It is preferable that the data (S_Vth, S_k) stored in the first memory (M1) is not updated.

The threshold voltage sensing data (S_Vth) and the mobility (S_Vth) for each of the plurality of sampling sub-pixels sampled by the sensing mode performed in the first driving operation after the product is shipped from the OLED display device And the sensing data S_k are stored. It is preferable that the data (S_Vth, S_k) stored in the second memory (M2) is not updated.

In the third memory M3, after the first driving of the organic light emitting diode display device, the above-described sensing mode performed every time the display panel 110 is driven for a long period of time, a restart timing after a long time, The threshold voltage sensing data S_Vth and the mobility sensing data S_k for each of the plurality of sampling subpixels sampled by the sampling transistor Ml are stored. The data (S_Vth, S_k) stored in the third memory (M3) is updated in each sensing mode.

The timing control unit 128 according to the first embodiment includes a control signal generation unit 128a, a four-color data conversion unit 128b, a compensation data calculation unit 128c, and a data modulation unit 128d.

The control signal generator 128a generates a data control signal DCS and a gate control signal GCS corresponding to the display mode or the sensing mode described above based on a timing synchronization signal TSS input from the outside, And supplies the gate control signal GCS to the row driver 122 and the data control signal DCS to the column driver 124. [

The four-color data conversion unit 128b converts red, green, and blue input data RGB of each unit pixel input from the outside into red, green, blue, and white pixel data R, G, ). For example, the four-color data conversion unit 128b converts input data RGB having a minimum gradation value (or a common gradation value) from red, green, and blue input data RGB of unit pixels into white pixel data Green, and blue pixel data R, G, and B by generating the white pixel data W in the red, green, and blue input data RGB, respectively, . At this time, the four-color data conversion unit 128b subtracts the white pixel data W from each of the red, green, and blue input data RGB, and outputs the pixel data R, G, , B), respectively.

The compensation data calculation unit 128c calculates the compensation data S_Vth and the mobility sensing data S_kh stored in the first through third memories M1, M2 and M3 of the memory unit 130, (P_Cdata) of each sub-pixel (P) on the basis of the calculated compensation data (P_Cdata).

Specifically, the compensation data calculation unit 128c compares the threshold voltage sensing data (S_Vth) of each of the same sampling sub-pixels stored in the second memory (M2) and the third memory (M3) of the memory unit 130 with the threshold voltage sensing data The mobility sensing data S_k are compared with each other and the deviation is reflected on the threshold voltage sensing data S_Vth and the mobility sensing data S_k of the corresponding sampling sub pixel stored in the first memory M1, (P_Cdata) for the corresponding sampling sub-pixel on the basis of the final threshold voltage sensing data and the final mobility sensing data of the corresponding sampling sub-pixel, and outputs the final threshold voltage sensing data and the final mobility sensing data of the sub- .

The data modulating unit 128d modulates the red, green, and blue signals to be supplied to the respective sub-pixels supplied from the four-color data converting unit 128b, based on the compensation data P_Cdata calculated by the compensation data calculating unit 128c. Green, blue and white modulation data R ', G', B 'and W' of the modulated red, green and blue pixel data R, G, B and W, respectively, And supplies it to a column driver 124. When the pixel data R, G, B, and W of the input sub-pixel correspond to the plurality of sampling sub-pixels, the data modulator 128d modulates the pixel data R, G, Green, blue and white modulation data R ', G', B ', and W' are directly reflected on the compensation data P_Cdata calculated by the compensation data calculation unit 128c, ). On the other hand, when the pixel data R, G, B, and W of the input sub-pixel do not correspond to the plurality of sampling sub-pixels, the data modulating unit 128d modulates the pixel data R, G, B, W) of the input sub-pixel by compensating the compensation data calculated by linear interpolation or averaging of the compensation data (P_Cdata) of the sampling sub-pixels adjacent to the respective sub-pixels (G, (R ', G', B ', W') of red, green, blue, and white. Therefore, the data modulator 128d modulates red, green, blue, and white modulated data R 'based on the threshold voltage sensing data S_Vth sensed by the sensing mode and the mobility sensing data S_k, , G ', B', W ') to compensate for the characteristic change of the driving transistor of each sub-pixel to make the luminance of the display panel 110 uniform.

12 is a view for explaining a memory unit and a timing controller according to a second embodiment of the present invention shown in FIG.

Referring to FIG. 12 with reference to FIG. 3, the memory unit 130 according to the second embodiment includes first to third memories M1, M2, and M3.

In the first memory M1, only the luminance component sensing data S_Y is stored for each unit pixel sampled by the above-described sensing mode, which is performed before shipment of the organic light emitting display device. It is preferable that the data S_Y stored in the first memory M1 is not updated.

In the second memory M2, only the luminance component sensing data S_Y is stored for each unit pixel sampled by the above-described sensing mode performed at the time of initial driving after the product is shipped from the OLED display. It is preferable that the data S_Y stored in the second memory M2 is not updated.

In the third memory M3, after the first driving of the organic light emitting diode display device, the above-described sensing mode performed every time the display panel 110 is driven for a long period of time, a restart timing after a long time, Only the luminance component sensing data S_Y is stored for each unit pixel sampled by the luminance component sensing data S_Y. The data S_Y stored in the third memory M3 is updated every sensing mode.

The timing controller 128 according to the second embodiment includes a control signal generator 328a, a luminance / color component generator 328b, a compensated luminance component calculator 328c, a data modulator 328d, And a generation unit 328e.

The control signal generator 328a generates a data control signal DCS and a gate control signal GCS corresponding to the display mode or the sensing mode described above on the basis of a timing synchronization signal TSS input from the outside, And supplies the gate control signal GCS to the row driver 122 and the data control signal DCS to the column driver 124. [

The luminance / color component generator 328b generates the luminance component (Y) and the first and second color components (RGB) of each unit pixel based on input data RGB of red, green, Cr, Cb). At this time, the luminance / chrominance data generator 328b can generate the luminance component Y and the first and second color components Cr and Cb of each unit pixel through the operation of Equation (2) .

Based on the luminance component sensing data S_Y of each unit pixel stored in each of the first to third memories M1, M2 and M3 of the memory unit 130, the compensation luminance component calculating unit 328c calculates the compensation luminance component The compensated luminance component C_Y of the pixel P is calculated. More specifically, the compensated luminance component calculating unit 328c calculates the compensated luminance component calculating unit 328c using the luminance component sensing data S_Y of the same unit pixel stored in the second memory M2 and the third memory M3 of the memory unit 130, And the deviation is reflected on the luminance component sensing data S_Y of the corresponding unit pixel stored in the first memory M1 to calculate the final luminance component sensing data of the unit pixel, And calculates a compensation luminance component (C_Y) for the unit pixel based on the component sensing data.

The data modulator 328d receives the luminance component Y of the corresponding unit pixel supplied from the luminance / color component generator 328b based on the compensated luminance component C_Y supplied from the compensated luminance component calculator 328c, And supplies the modulated luminance component Y 'of the unit pixel to the four-color modulation data generation section 328e. The first and second color components Cr and Cb of each unit pixel output from the luminance / color component generator 328b are supplied to the four-color modulated data generator 328e via the data modulator 328d It is bypassed.

The four-color modulation data generation unit 328e generates the four-color modulation data by using the modulated luminance component Y 'of each unit pixel supplied from the data modulation unit 328d and the modulated luminance component Y' of the corresponding unit pixel supplied from the luminance / color component generation unit 328b Green, and blue pixel data of each unit pixel based on the first and second color components (Cr, Cb). For example, the four-color modulation data generation unit 328e can calculate the red, green, and blue pixel data P_R, P_G, and P_B of each unit pixel through an operation expressed by Equation 3 below .

Then, the four-color modulation data generator 328e generates pixel data having the minimum gradation value (or common gradation value) in the red, green, and blue pixel data P_R, P_G, and P_B of each unit pixel, Green and blue modulation data (W '), and the generated white modulated data W' is reflected on the red, green and blue pixel data P_R, P_G and P_B, respectively, R ', G', B '). At this time, the 4-color modulation data generation unit 328e subtracts the white modulation data W 'from the red, green and blue pixel data P_R, P_G and P_B, respectively, Of the modulated data R ', G' and B ', respectively.

Therefore, the four-color modulation data generation unit 328e generates the four-color modulation data R 'and G' based on the luminance component sensing data S_Y of each unit pixel sensed by the sensing mode, , B ', and W') to compensate for the change in the characteristics of the driving transistor of each sub-pixel, thereby making the brightness of the display panel 110 uniform.

FIG. 13 is a diagram for explaining a memory unit and a timing controller according to a third embodiment of the present invention shown in FIG. 3. Referring to FIG.

Referring to FIG. 13 with reference to FIG. 3, the memory unit 130 according to the third embodiment includes first to third memories M1, M2, and M3.

In the first memory M1, the luminance component sensing data S_Y and the first and second color component sensing data S_Y of the sampling unit pixel are stored in the first memory M1 for each unit pixel sampled by the sensing mode, Data (S_Cr, S_Cb) and at least one data (S_Cr, S_Cb) are stored. It is preferable that the data (S_Y, S_Cr, S_Cb) stored in the first memory (M1) is not updated.

The second memory M2 stores luminance component sensing data S_Y for each unit pixel sampled by the above-described sensing mode performed at the time of initial driving after the product is shipped from the organic light emitting display device, Second color component sensing data S_Cr and S_Cb and at least one data S_Cr and S_Cb. It is preferable that the data (S_Y, S_Cr, S_Cb) stored in the second memory (M3) is not updated.

In the third memory M3, after the first driving of the organic light emitting diode display device, the above-described sensing mode performed every time the display panel 110 is driven for a long period of time, a restart timing after a long time, The first and second color component sensing data S_Cr and S_Cb of the sampling unit pixel and at least one data S_Cr and S_Cb are stored together with the luminance component sensing data S_Y for each unit pixel sampled by the sampling unit SX. The data (S_Y, S_Cr, S_Cb) stored in the third memory (M3) is updated in each sensing mode.

The timing controller 128 according to the third embodiment includes a control signal generator 428a, a luminance / color component generator 428b, a compensation luminance / color component calculator 428c, a luminance / color component modulator 428d, And a color modulation data generation section 428e.

The control signal generator 428a generates a data control signal DCS and a gate control signal GCS corresponding to the display mode or the sensing mode described above on the basis of a timing synchronization signal TSS input from the outside, And supplies the gate control signal GCS to the row driver 122 and the data control signal DCS to the column driver 124. [

The luminance / color component generator 428b generates the luminance component (Y) and the first and second color components (RGB) of each unit pixel based on input data RGB of red, green, Cr, Cb). At this time, the luminance / chrominance data generator 328b can generate the luminance component Y and the first and second color components Cr and Cb of each unit pixel through the operation of Equation (2) have.

The compensated luminance / color component calculator 428c calculates the compensated luminance / color component calculator 428c based on the luminance component sensing data S_Y of each unit pixel stored in each of the first to third memories M1, M2, and M3 of the memory unit 130, The compensated luminance component C_Y of each subpixel P and the first and second compensated color components S_Cr and S_Cb based on the first and second color component sensing data S_Cr and S_Cb of the unit pixel and the at least one data S_Cr and S_Cb, (C_Cr, C_Cb).

Specifically, the compensation luminance / color component calculator 428c calculates the compensated luminance / color component calculator 428c based on the luminance component sensing data S_Y of each of the unit pixels stored in the second memory M2 and the third memory M3 of the memory unit 130, And the deviation is reflected on the luminance component sensing data S_Y of the corresponding unit pixel stored in the first memory M1 to calculate the final luminance component sensing data of the unit pixel, And calculates a compensation luminance component (C_Y) for the unit pixel based on the luminance component sensing data.

The compensated luminance / color component calculator 428c calculates the compensated luminance / color component of each of the first and second color component sensing units of the same sampling unit pixel stored in the second memory M2 and the third memory M3 of the memory unit 130, (S_Cr, S_Cb) and at least one data (S_Cr, S_Cb), and compares the deviation with the first and second color component sensing data (S_Cr, S_Cb) of the corresponding sampling unit pixel stored in the first memory (M1) And at least one data (S_Cr, S_Cb) so as to calculate final first and second color component sensing data and at least one final color component data of the corresponding sampling unit pixel, and based on the calculated final color component data of the corresponding sampling unit pixel And calculates the first and second compensated color components C_Cr and C_Cb for the corresponding sampling unit pixel.

The luminance / color component modulating section 428d modulates the luminance component of the unit pixel supplied from the luminance / color component generating section 428b based on the compensated luminance component C_Y supplied from the compensating luminance / color component calculating section 428c (Y), and supplies the modulated luminance component (Y ') of each unit pixel to the four-color modulation data generation section 428e.

The luminance / color component modulating section 428d receives the luminance component from the luminance / color component generating section 428b based on the first and second compensating color components (C_Cr and C_Cb) supplied from the compensating luminance / color component calculating section 428c The first and second color components Cr and Cb of each unit pixel to be supplied are modulated and the modulated first and second color components Cr 'and Cb' of each unit pixel are supplied to the four-color modulation data generation unit 428e Supply.

Specifically, when the first and second color components (Cr, Cb) of the input unit pixel correspond to the plurality of sampling unit pixels, the luminance / color component modulating unit 428d modulates the first and second The first and second compensated color components C_Cr and C_Cb supplied from the compensation luminance / color component calculator 428c are directly reflected to the dichroic components Cr and Cb, respectively, and the modulated first and second And supplies the color components Cr 'and Cb' to the four-color modulation data generation section 428e.

On the other hand, when the first and second color components (Cr, Cb) of the input unit pixel do not correspond to the plurality of sampling unit pixels, the luminance / color component modulating unit 428d modulates the first and second Each of the first and / or second compensating color components is calculated by linear interpolation or averaging of each of the first and / or second compensating color components (C_Cr, C_Cb) of the sampling unit pixels adjacent to each of the second color components (Cr, Cb) (Cr and Cb) of the corresponding unit pixel and outputs the calculated first and second compensated color components to the first and second color components Cr and Cb of the corresponding unit pixel, respectively, Modulated and supplied to the four-color modulation data generation section 428e. When only the first compensated color component C_Cr of a plurality of sampling unit pixels is supplied from the compensated luminance / color component calculator 428c, the luminance / color component modulator 428d modulates the first compensated color component (Cr) of the corresponding unit pixel based on the calculated new first compensated color component, and outputs the modulated first color component (Cr) of the corresponding unit pixel, And supplies the one-color component (Cr ') to the four-color modulation data generation section 428e. When only the second compensated color component (C_Cb) of a plurality of sampling unit pixels is supplied from the compensated luminance / color component calculator 428c, the luminance / color component modulating unit 428d modulates the second compensated color component The second color component Cb of the corresponding unit pixel to be input is calculated based on the calculated new second color component, and the modulated color component Cb of the corresponding unit pixel is calculated by linearly interpolating or averaging the first color component Cb, And supplies the two-color component (C_Cb ') to the four-color modulation data generation section 428e.

The four-color modulation data generation section 428e generates the four-color modulation data by using the modulated luminance component Y 'of the unit pixel supplied from the luminance / color component modulating section 428d and the first and second color components Cr' and Cb ' And generates red, green, and blue pixel data of each unit pixel. For example, the 4-color modulation data generation unit 428e can calculate the red, green, and blue pixel data P_R, P_G, and P_B of each unit pixel through the calculation of Equation (3) .

Then, the four-color modulation data generation section 428e generates pixel data having the minimum gradation value (or common gradation value) in the red, green, and blue pixel data P_R, P_G, and P_B of each unit pixel, Green and blue modulation data (W '), and the generated white modulated data W' is reflected on the red, green and blue pixel data P_R, P_G and P_B, respectively, R ', G', B '). At this time, the 4-color modulation data generation unit 428e subtracts the white modulation data W 'from the red, green, and blue pixel data P_R, P_G, and P_B, Of the modulated data R ', G' and B ', respectively.

Accordingly, the four-color modulation data generation unit 428e generates the four-color modulation data by using the luminance component sensing data S_Y and the first and second color component sensing data S_Cr and S_Cb of each unit pixel sensed by the sensing mode, , G ', B', and W ') are generated to compensate for the characteristic change of the driving transistor of each sub-pixel to uniformize the brightness of the display panel (110).

14 is a waveform diagram showing driving waveforms in a display mode of an OLED display according to an embodiment of the present invention.

Referring to FIG. 14, the operation of the display mode for the sub-pixel P shown in FIG. 4 will be described with reference to FIGS. 3 and 4. FIG.

First, as described above with reference to any one of Figs. 11 to 13, the timing controller 128 described above senses by the sensing mode and drives each sub-pixel based on the sensing data stored in the memory unit 130 Green, blue, and white modulation data (R ', G', B ', W') in which the characteristic change of the transistor Tdr is compensated. The timing controller 128 controls the driving timing of the row driver 122 and the column driver 124 so that the sub pixel P is driven in the data charging period t1 and the light emitting period t2.

First, in the data charge period t1, the first and second gate signals GSa and GSb of the gate-on voltage level are applied to the first and second gate lines GLa And GLb and the data voltage Vdata converted from the modulated data R ', G', B 'and W' by the column driver 124 is supplied to the data line DLi The reference voltage Vref is supplied to the sensing line SLi. Thus, each of the first and second switching transistors Tsw1 and Tsw2 of the sub-pixel P is turned on by the first and second gate signals GSa and GSb of the gate-on voltage level, The data voltage Vdata is supplied to one node n1 and the voltage of the second node n2 is initialized to the reference voltage Vref. Accordingly, the capacitor Cst connected to the first node n1 and the second node n2 is charged with the difference voltage Vdata-Vref between the data voltage Vdata and the reference voltage Vref.

Subsequently, in the light emission period t2, the first and second gate signals GSa and GSb of the gate-off voltage level are applied to the first and second gate lines GLa and GLb by the row driver 122, Respectively. Accordingly, in the light emission period t2, the first and second switching transistors Tsw1 and Tsw2 of the subpixel P are respectively connected to the first and second gate signals GSa and GSb at the gate-off voltage level The driving transistor Tdr is turned on by the voltage stored in the capacitor Cst. Therefore, the turn-on driving transistor Tdr is controlled by the data current Ioled (Vdata) determined by the differential voltage (Vdata-Vref) between the data voltage (Vdata) and the reference voltage (Vref) To the light emitting device OLED so that the light emitting device OLED emits light proportional to the data current Ioled flowing from the driving voltage line PLi to the cathode electrode CE. That is, in the light emission period t2, when the first and second switching transistors Tsw1 and Tsw2 are turned off, a current flows through the driving transistor Tdr, and the light emitting device OLED emits light in proportion to the current The voltage of the second node n2 rises by the capacitor Cst and the voltage of the first node n1 rises by the voltage rise of the second node n2 by the capacitor Cst, The gate-source voltage Vgs of the driving transistor Tdr is continuously maintained so that the light emitting device OLED continues to emit light until the next data charging period t1.

In Equation (4), k is a proportional constant, and "W / L", which is the ratio of the mobility of the driving transistor DT and the channel width W and the channel length L of the driving transistor DT, Can be determined by the capacitance (C _OX ) of the insulating film constituting the driving transistor. In Equation (4), k is compensated according to the mobility sensing data S_k sensed by the sensing mode described above.

During the light emission period t2, the data current Ioled flowing through the light emitting device OLED is converted into the modulated data R ', G', and B corresponding to the characteristic changes of the driving transistor Tdr, Is determined by the difference between the data voltage (Vdata) and the reference voltage (Vref) without being influenced by the characteristic change of the driving transistor (Tdr) by the data voltage (Vdata) have.

Therefore, the organic light emitting display according to the embodiment of the present invention is based on the modulation data R ', G', B ', W' in which the characteristic change of the driving transistor Tdr of the subpixel P is reflected in the display mode It is possible to periodically or real-time compensate for the deviation of the characteristic change of the driving transistor Tdr of each sub-pixel P by driving each sub-pixel P. [

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 general inventive concept as defined by the appended claims and their equivalents. Will be clear to those who have knowledge of.

110: display panel 120:
130: memory unit 122: row driver
124: column driver 126: sensing data processor
128:

Claims (10)

A display panel including a plurality of unit pixels constituted by a plurality of sub-pixels, each sub-pixel including a driving transistor for emitting an organic light emitting element by using a data current based on a data voltage;
Wherein the sensing panel is operated in a sensing mode or a display mode, the threshold voltage and the mobility of the driving transistor of each sub-pixel are sensed in the sensing mode, and only the sensing data corresponding to the plurality of sampling pixels set on the display panel is sampled And a panel driver for storing the data voltage in the memory unit and modulating input data based on the sensing data stored in the memory unit in the display mode to generate the data voltage. The method according to claim 1,
The plurality of sampling pixels are each sub-pixel formed on an odd-numbered horizontal line or an even-numbered horizontal line of the display panel, or a sub-pixel of an odd-numbered or odd-numbered unit pixel based on a vertical direction of the display panel. To the organic light emitting display device. The method according to claim 1,
Wherein the plurality of sampling pixels are sub-pixels of unit pixels arranged in a zigzag pattern on the display panel among the plurality of unit pixels. The method according to claim 1,
Wherein the one unit pixel includes red, white, green, and blue sub-pixels,
Wherein the plurality of sampling pixels are one or two sub-pixels of red, green, and blue sub-pixels that are the same or different from one another for each of the white sub-pixels of each unit pixel and each unit pixel. Organic light emitting display. 5. The method according to any one of claims 1 to 4,
Wherein the panel-
Pixels in the sensing mode to generate sensing data of each sub-pixel by sensing a threshold voltage and a mobility of the driving transistor of each sub-pixel, and to convert the modulation data of each sub-pixel into the data voltage in the display mode Column driver;
A sensing data processing unit for sampling sensing data corresponding to the plurality of sampling pixels among the sensing data of each sub pixel during the sensing mode and storing the sampled sensing data in the memory unit; And
Pixel in the display mode, generates compensation data of each sub-pixel based on the sensing data stored in the memory, modulates input data of each of the sub-pixels based on the generated compensation data, And a timing controller for generating data and supplying modulation data of each sub-pixel to the column driving unit. The method according to claim 1,
Wherein the panel-
Pixels in the sensing mode to generate sensing data of each sub-pixel by sensing a threshold voltage and a mobility of the driving transistor of each sub-pixel, and to convert the modulation data of each sub-pixel into the data voltage in the display mode Column driver;
The sensing unit may calculate luminance component sensing data and first and second color component sensing data of each unit pixel based on sensing data of each sub-pixel during the sensing mode, and output luminance component sensing data corresponding to the plurality of sampling pixels A sensing data processor for sampling the first and second color component sensing data and storing the sampled data in the memory; And
Wherein the compensation data generating unit generates compensation data of each sub pixel based on the luminance component sensing data and the first and second color component sensing data stored in the memory unit in the display mode, And a timing controller for generating modulation data of each sub-pixel by modulating the input data of the sub-pixel and supplying the modulated data of each sub-pixel to the column driver. Device. The method according to claim 6,
Wherein the sensing data processing unit samples only the luminance component sensing data of each unit pixel and stores the sampled data in the memory unit. 8. The method of claim 7,
Wherein the timing control unit generates the luminance component and the first and second color components of each unit pixel based on the input data of each unit pixel and outputs the luminance component of each unit pixel based on the luminance component sensing data of each unit pixel stored in the memory unit And generates modulation data to be supplied to each of the sub pixels based on the modulated luminance component of each unit pixel and the first and second color components of the unit pixel, Display device. The method according to claim 6,
The sensing data processing unit samples luminance component sensing data of each unit pixel and stores the sampled luminance component sensing data in the memory unit and samples at least one color component sensing data among first and second color component sensing data corresponding to the plurality of sampling pixels And wherein the organic light emitting diode (OLED) display unit stores the image data in the memory unit. 10. The method of claim 9,
Wherein the timing control unit generates the luminance component and the first and second color components of each unit pixel based on the input data of each unit pixel and outputs the luminance component of each unit pixel based on the luminance component sensing data of each unit pixel stored in the memory unit The first and second color components and at least one color component of each unit pixel based on at least one color component sensing data of the first and second color component sensing data stored in the memory unit, And generates modulation data to be supplied to each sub-pixel based on the modulated luminance component of each unit pixel and the first and second modulated color components.

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