KR100830979B1 - Organic lighting emitting diode display device and the driving method thereof - Google Patents

Abstract

The organic light emitting display device according to the present invention receives an external signal, measures a data transmission start period, generates a first signal according to the measurement result, and generates a control signal using the first signal. Using a vertical sync signal, a horizontal sync signal, and a dot clock included in an external signal, sample the data transmission start period, and if the sampled data transmission start period has at least two values, Set as a transmission start period, and generates a control signal using the first signal.

OLED, dot clock, horizontal synchronous signal, vertical synchronous signal

Description

Organic light emitting display device and its driving method {ORGANIC LIGHTING EMITTING DIODE DISPLAY DEVICE AND THE DRIVING METHOD THEREOF}

 1 is a diagram schematically illustrating a configuration of an organic light emitting display device according to an exemplary embodiment of the present invention.

2 is a view showing in detail the vertical synchronization signal, the horizontal synchronization signal and the dot clock according to an embodiment of the present invention.

3 is a flowchart illustrating a method of driving an organic light emitting display device according to an embodiment of the present invention.

The present invention relates to a light emitting display device and a driving method thereof, and more particularly, to an organic light emitting display device using light emission of an organic material and a driving method thereof.

In general, an organic light emitting display device is a display device using an organic light emitting device using light emission of an organic material. An organic light emitting display device displays an image by voltage driving or current driving N ㅧ M organic light emitting cells arranged in a matrix form. The organic electroluminescent cell has a diode characteristic and is also called an organic light emitting diode (OLED), and has an anode, an organic thin film, and a cathode electrode layer.

The organic electroluminescent device uses an RGB interface driving method, and in order to transmit data, a vertical synchronization signal (Vsync) for dividing a frame and a horizontal synchronization signal (Hsync) for adjusting the timing of one line are required. However, the vertical synchronizing signal and the horizontal synchronizing signal may include an irregular section due to an external environment, noise, or an error of the transmission source source itself. As a result, an error occurs in the scan signal and the data signal generated inside the organic light emitting device, and thus, normal display may not be possible.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an organic light emitting display device and a driving method thereof capable of stably displaying an image without being influenced by an external environment.

An organic light emitting display device according to an aspect of the present invention includes a plurality of data lines for transmitting a data signal, a plurality of scan lines for transmitting a scan signal, a plurality of pixels defined by the data lines and the scan lines, each pixel having a pixel circuit, A data driver for generating the data signal, a scan driver for generating the scan signal, and an external signal, receiving a data transmission start period, measuring a data transmission start period, generating a first signal according to a measurement result, and using the first signal And a signal controller for generating a control signal. The signal controller samples the data transmission start period using a vertical synchronization signal, a horizontal synchronization signal, and a dot clock included in the external signal, and the sampled data transmission start period is at least two values. If a value is larger, a larger value is set as a data transmission start period, and the control signal is generated using the first signal. At this time, the first number of times of the horizontal synchronization signal having the second level corresponding to the section which is the first level of the vertical synchronization signal is detected, and the dot clock is counted during the period where the horizontal synchronization signal is the second level. The second number of times is counted, and the data transmission start period is sampled using the first and second times. The first signal includes an internal vertical synchronization signal and an internal horizontal synchronization signal.

A method of driving an organic light emitting display device which receives an external signal and generates a control signal, the method comprising: a) receiving an external signal and measuring a data transmission start period; b) the a) Generating a first signal according to the measurement result of step c) generating a control signal using the first signal. In step a), the data transmission start period is sampled using a vertical synchronization signal, a horizontal synchronization signal, and a dot clock included in the external signal. In step b), if the sampled data transmission start period has at least two values, the first signal is generated, and a larger value of the at least two values is set as the data transmission start period. In this case, the step a) detects a first number of times of the horizontal synchronization signal having a second level corresponding to a period that is the first level of the vertical synchronization signal, and during the period where the horizontal synchronization signal is the second level. The dot clock is counted to count a second number, and the data transmission start period is sampled using the first and second counts. The first signal includes an internal vertical synchronization signal and an internal horizontal synchronization signal.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "electrically connected" between other elements in between. In addition, when any part "includes" any component, this means that it may further include other components, except to exclude other components unless otherwise stated.

1 is a diagram schematically illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

As shown in FIG. 1, an organic light emitting display device according to an exemplary embodiment of the present invention includes a display unit 100, a scan driver 200, a data driver 300, and a signal controller 400.

The display unit 100 includes a plurality of scan lines S1 -Sn, a plurality of data lines D1 -Dm, and a plurality of pixels 110. The plurality of scan lines S1 -Sn extend in a row direction and each transmit a selection signal, and the plurality of data lines D1 -Dm extend in a column direction and each transmit a data signal. Each pixel 110 is formed in a pixel region defined by a corresponding scan line among the plurality of scan lines S1 -Sn and a corresponding data line among the plurality of data lines D1 -Dm. In this case, the data signal is a current when the pixel 110 is a current write type pixel, and the data signal is a voltage when the pixel is a voltage write type pixel.

Meanwhile, in order to implement color display, each pixel uniquely displays one color of the primary colors or each pixel alternately displays the primary colors with time, so that the desired color is recognized by the spatial or temporal sum of these primary colors. Examples of primary colors include red (R), green (G), and blue (B). In this case, when colors are displayed by a time sum, R, G, and B colors are alternately displayed in one pixel to realize one color. In the case of displaying colors by spatial sum, one color is implemented by three pixels of the R pixel, the G pixel, and the B pixel, so that each pixel is referred to as a subpixel and three subpixels are referred to as one pixel. In addition, in the case of displaying colors by spatial sum, R pixels, G pixels, and B pixels may be alternately arranged in a row direction or a column direction, or three pixels may be arranged at positions corresponding to three vertices of a triangle. .

The scan driver 200 is connected to the scan lines S1 -Sn of the display unit 100 to apply a selection signal formed of a combination of a gate on voltage and a gate off voltage to the scan lines S1 -Sn. In this case, the scan driver 200 may apply the selection signal such that the plurality of selection signals respectively applied to the plurality of scan lines S1 -Sn have the gate on voltage. When the selection signal has a gate-on voltage, the switching transistor connected to the corresponding scan line is turned on.

The data driver 300 is connected to the data lines D1 -Dm of the display unit 100 to apply a data signal indicating a gray level to the data lines D1 -Dm. The data driver 300 converts input image data DR, DG, and DB having a gray level input from the signal controller 400 into a data signal in the form of voltage or current.

The signal controller 400 receives an external signal transmitted from an external graphic controller (not shown), that is, input image signals DR, DG, and DB, and an input control signal for controlling the display thereof. The input control signal includes, for example, a horizontal sync signal Hsync, a vertical sync signal Vsync, and a dot clock dclk. The signal controller 400 transmits the input image data DR, DG, and DB to the data driver 300, generates a control signal, and transmits the control signal to the scan driver 200 and the data driver 300. The control signal includes the scan control signal CONT1 and the data control signal CONT2, and the signal controller 400 generates the scan control signal CONT1 and the data control signal CONT2 to generate the scan driver 200 and the data, respectively. Transfer to the driver 300. The scan control signal CONT1 includes a scan start signal SP indicating the scan start and the first and second clock signals CLK and CLKB, and the data control signal CONT2 includes one pixel 110 in a row. And a horizontal synchronization start signal (STH) and a clock signal (CLK) for instructing transfer of input image data.

In detail, the signal controller 400 generates the scan control signal CONT1 and the data control signal CONT2, and includes the horizontal sync signal Hsync, the vertical sync signal Vsync, and the dot clock that are input control signals. A clock (hereinafter referred to as "dclk") is used to determine whether external signals are abnormal. If the external signal is abnormal as a result of the determination, the signal controller 400 generates an internal signal instead of the external signal or uses the set internal signal.

On the other hand, the signal controller 400 may transmit the input image data (DR, DG, DB) for each color through the three channels when the input image data corresponding to one row to the data driver 300, Input image data DR, DG, and DB may be sequentially transmitted through one channel.

The signal controller 400, the scan driver 200, and the data driver 300 may be electrically connected to the display panel 100, or may be attached to the display panel 100 and electrically connected to the tape carrier package. , TCP) can be mounted in the form of a chip. Alternatively, the display panel 100 may be mounted in a flexible printed circuit (FPC) or a film that is adhered to and electrically connected to the display panel 100 in the form of a chip. Alternatively, the signal controller 400, the scan driver 200, and the data driver 300 may be directly mounted on the glass substrate of the display panel, or may be formed of the same layers as the scan line, the data line, and the thin film transistor on the glass substrate. It may be replaced with a drive circuit or directly mounted.

Hereinafter, a driving method of a signal controller in an organic light emitting display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 2.

FIG. 2 illustrates a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a dot clock dclk, an enable signal ENABLE, and input image data DAS according to an embodiment of the present invention.

The vertical synchronization signal Vsync is a signal for distinguishing a frame. In the organic light emitting display device according to an exemplary embodiment of the present invention, the time from the time when the vertical synchronization signal is low to the next time is low Period of the frame. The horizontal sync signal Hsync is used to determine the timing of delivering the scan signal to the plurality of scan lines during one frame period. The dot clock is used to generate a clock of several cycles, such as a clock driver for driving a data shift in a scan driver and a data driver. The enable signal ENABLE is a signal indicating a period during which the data signal is transferred to the data line. The enable signal ENABKE according to the embodiment of the present invention is maintained at a low level during a period in which a plurality of data signals corresponding to one row are transmitted. As shown in FIG. 2, the horizontal synchronization signal of one cycle is described in detail. A plurality of data signals are transferred to the data line during the T1 period when the enable signal is at a low level. At this time, the data transmission start period (hereinafter referred to as "dtst") is a time from the start point of one period of the horizontal synchronization signal to the period when the data signal starts to be transmitted to the data line.

Hereinafter, a driving method of an organic light emitting display device according to an exemplary embodiment of the present invention will be described with reference to FIG. 3.

3 is a view illustrating a driving method of an organic light emitting display device.

First, the signal controller classifies the first frame from the outside using a vertical synchronization signal and detects a predetermined number of horizontal synchronization signals from the beginning of the frame. In detail, n horizontal synchronization signals are detected from a timing at which the vertical synchronization signal falls to a low level (S100). The signal controller counts the number of dot clocks corresponding to the row sections of the detected n horizontal synchronization signals (S200). The signal controller measures the data transmission start section dtst according to the count result. In detail, the data transmission start section is sampled using the number of n clocks and the number of dot clocks corresponding to the row sections of the horizontal synchronization signals (S300). The signal controller 400 determines whether the sampled dtst has a plurality of values (S400). As a result of the determination in step S400, when dtst has a plurality of values, the signal controller selects a large value and uses its own internal signals, that is, internal vertical synchronization signals and internal horizontal synchronization signals, regardless of the next external signal ( S500). If the result of the determination in step S400 dtst has a constant value, an external signal is used (S550). The signal controller according to an exemplary embodiment of the present invention may preset internal vertical synchronization signals and horizontal synchronization signals.

The signal controller 400 according to an exemplary embodiment of the present invention may set a restriction condition for an internal vertical synchronous signal, a horizontal synchronous signal, and dtst. Specifically, the low level section of the horizontal sync signal should be at least one period of the horizontal sync signal, and the low level section of the horizontal sync signal should be at least one period of the dot clock. Dtst is 5 to 10 dot clock when one frame includes 256 dot clock cycles, and 5 to 20 dot clock cycles when one frame corresponds to 300 dot clock cycles. Should be.

As described above, when it is determined that the external condition is influenced by dtst, the organic light emitting display according to the exemplary embodiment of the present invention uses an internal horizontal synchronization signal and a vertical synchronization signal. This can prevent malfunction due to logic signals.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

According to the present invention, there is provided an organic electroluminescent display and a driving method thereof capable of stably displaying an image without being influenced by an external environment.

Claims (9)

An organic light emitting display device driven according to an external signal including input image data and an input control signal for controlling the display thereof. A plurality of data lines transferring a data signal corresponding to the input image data; A plurality of scan lines for transmitting scan signals, A plurality of pixels defined by the data line and the scanning line and each having a pixel circuit, A data driver for generating the data signal, A scan driver for generating the scan signal, and A signal controller configured to receive the external signal, measure a data transmission start period, and select one of the external signal and an internal signal different from the external signal according to a measurement result, and generate a control signal corresponding to the selected signal Organic light emitting display device comprising a. The method of claim 1, The signal control unit, Sampling the data transmission start period using a vertical sync signal, a horizontal sync signal and a dot clock included in the external signal, and if the sampled data transmission start period has at least two different values, An organic light emitting display device which sets a large value as a data transmission start period and generates the control signal using the internal signal. The method of claim 2, The signal control unit, Detecting a first number of times of the horizontal synchronization signal having a second level corresponding to a period that is the first level of the vertical synchronization signal, and counting the dot clock during the period where the horizontal synchronization signal is the second level; And counting the number of times, and sampling the data transmission start period using the first and second times. The method according to any one of claims 1 to 3, And the internal signal includes an internal vertical synchronization signal and an internal horizontal synchronization signal. A driving method of an organic light emitting display device for receiving an external signal including input image data and an input control signal for controlling a display thereof, and generating a control signal. a) receiving an external signal and measuring a data transmission start period b) selecting any one of the external signal and the internal signal different from the external signal according to the measurement result of step a); and c) generating a control signal corresponding to the selected signal using the signal selected in step b) Method of driving an organic light emitting display device comprising a. The method of claim 5, Step a) is A method of driving an organic light emitting display device, wherein the data transmission start period is sampled by using a vertical synchronization signal, a horizontal synchronization signal, and a dot clock included in the external signal. The method of claim 6, Step a) is The first number of times the horizontal synchronization signal becomes the second level is detected during the first level of the vertical synchronization signal, and the dot clock is counted during the period where the horizontal synchronization signal is the second level. And counting and sampling the data transmission start period using the first and second times. The method of claim 5, Step b), A method of driving the organic light emitting display device, wherein the internal signal is selected if the data transmission start period measured in step a) has at least two different values; The method according to any one of claims 5 to 8, And the internal signal includes an internal vertical synchronization signal and an internal horizontal synchronization signal.

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