KR100707629B1 - Light Emitting Display and Driving Method Thereof - Google Patents

Abstract

The present invention relates to a light emitting display device capable of preventing motion blur.

The light emitting display device of the present invention includes a scan driver for driving a plurality of scan lines; A data driver supplying a data signal to the plurality of data lines; An image display portion connected to the scanning lines and the data lines, the image display portion including pixels for controlling an amount of current flowing from a first power supply to a second power supply via a light emitting element in response to the data signal; The data driver provides a light emitting display device that supplies the same voltage as the first power source as the data signal during at least one frame period of a plurality of frames.

By such a configuration, the present invention can prevent the motion blur phenomenon.

Description

Light Emitting Display and Driving Method Thereof

1 is a view showing a general light emitting device.

2 is a view showing a light emitting display device according to a first embodiment of the present invention;

FIG. 3 is a waveform diagram showing a driving waveform supplied to the scanning line and the data line shown in FIG.

4 is a circuit diagram illustrating an embodiment of a pixel illustrated in FIG. 2.

5A and 5B show data signals supplied from the data driver shown in FIG. 2 during a plurality of frame periods.

6 is a view showing a light emitting display device according to a second embodiment of the present invention;

FIG. 7 is a waveform diagram showing driving waveforms supplied to the scanning line, data line and emission control line shown in FIG. 6; FIG.

FIG. 8 is a circuit diagram illustrating an embodiment of a pixel illustrated in FIG. 6.

<Explanation of symbols for the main parts of the drawings>

20: anode electrode 21: cathode electrode

110,210: scan driver 120: data driver

130: image display unit 140,200: pixel

142,202 pixel circuit 150 timing controller

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting display device and a driving method thereof, and more particularly, to a light emitting display device and a driving method thereof capable of preventing a motion blur phenomenon.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. The flat panel display includes a liquid crystal display, a field emission display, a plasma display panel, a light emitting display, and the like.

Among flat panel display devices, the light emitting display device includes a plurality of light emitting devices, and the light emitting devices generate predetermined light by recombination of electrons and holes. Such a light emitting display device has an advantage in that it has a fast response speed and is driven with low power consumption.

1 is a view showing a conventional general light emitting device.

Referring to FIG. 1, the light emitting device includes an emission layer (EL), a hole transfer layer (HTL), and an electron transport layer (ETL) formed between the anode electrode 20 and the cathode electrode 21. ).

The anode electrode 20 is connected to the first power source to supply holes to the light emitting layer EL. The cathode electrode 21 is connected to a second power source lower than the first power source to supply electrons to the light emitting layer EL. That is, the anode electrode 20 has a higher potential of positive polarity (+) than the cathode electrode 21, and the cathode electrode 21 has a relatively low polarity (−) than the anode electrode 20. Has a potential.

The hole transport layer HTL accelerates holes supplied from the anode electrode 20 and supplies them to the light emitting layer EL. The electron transport layer ETL accelerates and supplies electrons supplied from the cathode electrode 21 to the emission layer EL. Holes supplied from the hole transport layer HTL and electrons supplied from the electron transport layer ETL recombine in the emission layer EL. At this time, predetermined light is generated in the light emitting layer EL. Subsequently, the emission layer EL is formed of an organic material to generate light of one of red (R), green (G), and blue (B) when electrons and holes recombine.

Meanwhile, the light emitting device includes a hole injection layer (HIL) located between the hole transport layer (HTL) and the anode electrode 20, and an electron injection layer located between the electron transport layer (ETL) and the cathode electrode 21. (Electron Injection Layer: EIL) is further included. The hole injection layer HIL supplies holes to the hole transport layer HTL. The electron injection layer EIL supplies electrons to the electron transport layer ETL.

Such a light emitting device is provided for each pixel of the light emitting display to generate a predetermined light corresponding to the current supplied to the light emitting device. Here, each pixel includes at least one capacitor for supplying current to the light emitting element during the frame period. That is, in the conventional light emitting display device, a predetermined voltage is charged in a capacitor provided for each pixel, and a predetermined current is supplied to the light emitting device by using the charged voltage.

However, as shown in the related art, when a predetermined image is displayed on a pixel during each frame period by using a voltage charged in a capacitor, a motion blur phenomenon occurs. That is, when the current corresponding to the voltage charged in the capacitor is continuously supplied to the light emitting device, a motion blur phenomenon occurs in which the image is blurred due to the afterimage effect of eyes when displaying a moving image. When such a motion blur occurs, the display quality of the light emitting display device is degraded.

Accordingly, an object of the present invention is to provide a light emitting display device and a driving method thereof capable of preventing a motion blur phenomenon.

In order to achieve the above object, the first aspect of the present invention includes a scan driver for driving a plurality of scan lines; A data driver supplying a data signal to the plurality of data lines; An image display portion connected to the scanning lines and the data lines, the image display portion including pixels for controlling an amount of current flowing from a first power supply to a second power supply via a light emitting element in response to the data signal; The data driver provides a light emitting display device that supplies the same voltage as the first power source as the data signal during at least one frame period of a plurality of frames.

Preferably, the plurality of frames are frames included in one second. Each of the pixels may include a first transistor connected to a scan line and a data line, a storage capacitor for charging a voltage corresponding to the data signal when the first transistor is turned on, and a voltage corresponding to a voltage charged in the storage capacitor. A second transistor for controlling the current supplied to the light emitting device is provided. And a third transistor connected between the second transistor and the light emitting element to control a supply time of a current supplied from the second transistor to the light emitting element in response to a light emission control signal supplied from a light emitting control line. .

A second aspect of the present invention includes supplying a data signal corresponding to data to a data line, and supplying a predetermined current from a first power supply to a light emitting element included in each of the pixels in response to the data signal. And supplying the same voltage as the first power supply to the data lines for at least one specific frame period of a plurality of frames.

Preferably, the plurality of frames are frames included in one second.

According to a third aspect of the present invention, there is provided a data signal for displaying a black screen on an image display unit during at least one or more specific frame periods among a plurality of frames included in one second. In response to the present invention, there is provided a driving method of a light emitting display device including displaying a black screen on the image display unit.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 2 to 8 that can be easily implemented by those skilled in the art.

2 is a diagram illustrating a light emitting display device according to a first embodiment of the present invention.

Referring to FIG. 2, the light emitting display device according to the first embodiment of the present invention includes an image display unit including pixels 140 formed in an intersection area between scan lines S1 to Sn and data lines D1 to Dm. 130, the scan driver 110 for driving the scan lines S1 to Sn, the data driver 120 for driving the data lines D1 to Dm, the scan driver 110 and the data driver 120. ), A timing controller 150 for controlling.

The timing controller 150 generates a data drive control signal DCS and a scan drive control signal SCS using a synchronization signal supplied from the outside. The data driving control signal DCS generated by the timing controller 150 is supplied to the data driver 120, and the scan driving control signal SCS is supplied to the scan driver 110. The timing controller 150 supplies the data Data supplied from the outside to the data driver 120.

The scan driver 110 receives the scan driving control signal SCS from the timing controller 150. The scan driver 110 supplied with the scan driving control signal SCS sequentially supplies the scan signals to the first scan line S1 to the nth scan line Sn as shown in FIG. 3.

The data driver 120 receives the data drive control signal DCS from the timing controller 150. The data driver 120 receiving the data driving control signal DCS generates a data signal and supplies the generated data signal to the data lines D1 to Dm. Here, the data driver 120 supplies the data signal DS to the data lines D1 to Dm whenever the scan signal is supplied as shown in FIG. 3. The data driver 120 supplies the same voltage as the first power source ELVDD to the data lines D1 to Dm as a data signal for at least one frame period of the plurality of frames, thereby displaying a black screen on the image display unit 130. do. Detailed description thereof will be described later.

The image display unit 130 receives the first power source ELVDD and the second power source ELVSS. The first power source ELVDD and the second power source ELVSS supplied to the image display unit 130 are supplied to the respective pixels 140.

4 is a circuit diagram illustrating a pixel of the light emitting display device illustrated in FIG. 2. In FIG. 4, for convenience of explanation, the pixel connected to the nth scan line Sn and the mth data line Dm will be illustrated.

Referring to FIG. 4, the pixel 140 of the present invention is connected to a light emitting element OLED, a light emitting element OLED, a data line Dm, and a scanning line Sn to emit light of the light emitting element OLED. A circuit 142 is provided.

The anode of the light emitting device OLED is connected to the pixel circuit 142, and the cathode is connected to the second power source ELVSS. The light emitting device OLED generates light corresponding to a current supplied from the pixel circuit 142.

The pixel circuit 142 is connected between the second transistor M2 connected between the first power supply ELVDD and the light emitting device OLED, and between the second transistor M2, the data line Dm, and the scan line Sn. The first transistor M1 and a storage capacitor C are connected between the gate electrode of the second transistor M2 and the first power source ELVDD.

The gate electrode of the first transistor M1 is connected to the scan line Sn, and the first electrode is connected to the data line Dm. The second electrode of the first transistor M1 is connected to one side of the storage capacitor C and the gate electrode of the second transistor M2. Here, the first electrode is set to any one of a source electrode and a drain electrode, and the second electrode is set to an electrode different from the first electrode. The first transistor M1 is turned on when the scan signal is supplied from the scan line Sn to supply the data signal supplied from the data line Dm to the storage capacitor C. At this time, the storage capacitor C is charged with a voltage corresponding to the data signal.

The gate electrode of the second transistor M2 is connected to one side of the storage capacitor C, and the first electrode is connected to the first power source ELVDD. The second electrode of the second transistor M2 is connected to the anode electrode of the light emitting element OLED. The second transistor M2 controls the amount of current flowing from the first power supply ELVDD to the light emitting device OLED in response to the voltage stored in the storage capacitor C. In this case, the light emitting device OLED generates light having luminance corresponding to the amount of current supplied from the second transistor M2.

5A and 5B are diagrams showing data signals supplied from a data driver.

5A and 5B, the data driver 120 of the present invention may generate a data signal during at least one specific frame period of a plurality of frames (for example, frames included in one second 1S). Supply the voltage of one power supply (ELVDD). The data driver 120 supplies the data signal DS corresponding to the data Data as the data signal for the remaining frame period except for the specific frame.

Then, during the frame period during which the data signal DS corresponding to the data Data is supplied, the image display unit 130 displays a predetermined image corresponding to the data Data. Then, a black screen is displayed on the image display unit 130 for at least one specific frame period in which the first power source ELVDD is supplied as the data signal DS.

In detail, the voltage of the first power supply ELVDD supplied from the data driver 120 is supplied to one side of the storage capacitor C via the first transistor M1 during a specific frame period. At this time, the same voltage (voltage of ELVDD) is applied to both sides of the storage capacitor (C). Therefore, no voltage is charged in the storage capacitor C during a specific frame period.

When the voltage is not charged to the storage capacitor C, the second transistor M2 is turned off and the current is not supplied to the light emitting element OLED for a specific frame period. Accordingly, the image display unit 130 during the specific frame period The black screen is displayed. When a black screen is displayed on the image display unit 130 for a specific frame period, the motion blur phenomenon may be prevented from occurring in the image display unit 130. That is, in the present invention, the light is generated in the pixels 140 during at least one specific frame period of the plurality of frames to prevent the motion blur from occurring.

6 is a diagram illustrating a light emitting display device according to a second embodiment of the present invention. 6, the same components as those in FIG. 2 are assigned the same reference numerals, and detailed description thereof will be omitted.

Referring to FIG. 6, the light emitting display device according to the second embodiment of the present invention includes a plurality of pixels 200 positioned in the image display unit 130 and a scan driver for driving the scan lines S1 to Sn. 210, a data driver 120 for driving the data lines D1 to Dm, and a timing controller 150 for controlling the scan driver 210 and the data driver 120.

The data driver 120 supplies the voltage of the first power source ELVDD as a data signal during at least one specific frame period of a plurality of frames (for example, frames included in one second 1S) to display the image display unit. In step 130, the black screen is displayed. As such, when the black screen is displayed on the image display unit 130 for a specific frame period, motion blur may be prevented. The data driver 120 supplies a data signal DS corresponding to the data Data for the remaining frame periods except for a specific frame period, thereby displaying a predetermined image corresponding to the data in the image display unit 130. do.

The scan driver 210 receives a scan driving control signal SCS from the timing controller 150. The scan driver 210 supplied with the scan driving control signal SCS sequentially supplies the scan signals to the first scan line S1 to the n th scan line Sn as shown in FIG. 7. The scan driver 210 receiving the scan driving control signal SCS sequentially supplies the emission control signal to the first emission control line E1 to the nth emission control line En. Here, the width of the light emission control signal is set to be equal to the width of the scan signal or wider than the width of the scan signal. For example, the light emission control signal may be supplied to overlap two scan signals.

The pixels 200 are positioned to be connected to the scan line S, the data line D, and the emission control line E. FIG. When the scan signal is supplied to the scan line S, the pixels 200 emit light corresponding to the data signal DS supplied from the data line D. Here, the emission time of the pixels 200 is controlled by the emission control signal supplied to the emission control line E.

FIG. 8 is a diagram illustrating an embodiment of a pixel illustrated in FIG. 6. In FIG. 8, for convenience of description, the pixel connected to the nth scan line Sn and the mth data line Dm will be illustrated.

Referring to FIG. 8, the pixel 200 of the present invention is connected to the light emitting device OLED, the light emitting device OLED, the data line Dm, the light emission control line En, and the scanning line Sn to form a light emitting device ( And a pixel circuit 202 for emitting light of the OLED.

The anode electrode of the light emitting element OLED is connected to the pixel circuit 202, and the cathode electrode is connected to the second power source ELVSS. The light emitting device OLED generates light corresponding to a current supplied from the pixel circuit 202.

The pixel circuit 202 includes a second transistor M2 and a third transistor M3 connected between the first power supply ELVDD and the light emitting device OLED, the second transistor M2, the data line Dm, The first transistor M1 is connected between the scan lines Sn, and the storage capacitor C is connected between the gate electrode of the second transistor M2 and the first power source ELVDD.

The gate electrode of the first transistor M1 is connected to the scan line Sn, and the first electrode is connected to the data line Dm. The second electrode of the first transistor M1 is connected to one side of the storage capacitor C and the gate electrode of the second transistor M2. The first transistor M1 is turned on when the scan signal is supplied from the scan line Sn to supply the data signal supplied from the data line Dm to the storage capacitor C. At this time, the storage capacitor C is charged with a voltage corresponding to the data signal.

The gate electrode of the second transistor M2 is connected to one side of the storage capacitor C, and the first electrode is connected to the first power source ELVDD. The second electrode of the second transistor M2 is connected to the first electrode of the third transistor M3. The second transistor M2 controls the amount of current flowing from the first power supply ELVDD to the light emitting device OLED in response to the voltage stored in the storage capacitor C.

The gate electrode of the third transistor M3 is connected to the emission control line En, and the first electrode is connected to the second electrode of the second transistor M2. The second electrode of the third transistor M3 is connected to the light emitting element OLED. The third transistor M3 is turned on when the emission control signal is not supplied to supply the current supplied from the second transistor M2 to the light emitting device OLED. That is, the third transistor M3 controls the supply time of the current supplied from the second transistor M2 to the light emitting device OLED.

The above detailed description and drawings are merely exemplary of the present invention, which are used only for the purpose of illustrating the present invention and are not intended to limit the scope of the present invention as defined in the claims or the claims. Accordingly, those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical protection scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

As described above, the light emitting display device and the driving method thereof according to the embodiment of the present invention provide a black display unit by supplying the same voltage value as the first power supply as the data signal during at least one specific frame period of the plurality of frames. Displays the screen. As such, when the black screen is displayed during at least one specific frame period among the plurality of frames, a motion blur phenomenon can be prevented, thereby improving display quality.

Claims (7)

A scan driver for driving the plurality of scan lines; A data driver supplying a data signal to the plurality of data lines; An image display portion connected to the scanning lines and the data lines, the image display portion including pixels for controlling an amount of current flowing from a first power supply to a second power supply via a light emitting element in response to the data signal; And the data driver supplies a voltage equal to the first power supply as the data signal during at least one frame period of a plurality of frames. The method of claim 1, Wherein the plurality of frames are frames included in one second. The method of claim 1 Each of the pixels A first transistor connected to the scan line and the data line; A storage capacitor for charging a voltage corresponding to the data signal when the first transistor is turned on; And a second transistor for controlling a current supplied to the light emitting device in response to the voltage charged in the storage capacitor. The method of claim 3, And a third transistor connected between the second transistor and the light emitting element to control a supply time of a current supplied from the second transistor to the light emitting element in response to a light emission control signal supplied from a light emission control line. Light emitting display. Supplying a data signal corresponding to the data to the data line; Supplying a predetermined current from a first power supply to a light emitting device included in each of the pixels in response to the data signal, And supplying the same voltage as the first power supply to the data lines during at least one specific frame period of a plurality of frames. The method of claim 5, And the plurality of frames are frames included in one second. Supplying a data signal so that the black screen can be displayed on the image display unit during at least one specific frame period of the plurality of frames included in one second; And displaying a black screen on the image display unit in response to the data signal during the specific frame period.

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