KR101821716B1 - Organic light emitting diode display and method of driving the same - Google Patents

Abstract

The organic light emitting display of the present invention includes: an organic light emitting panel defining a plurality of subpixels constituting each of a plurality of pixels by intersecting a plurality of gate wirings and a plurality of data wirings; In case of driving in the normal mode, the input RGB data is sorted and output to the plurality of sub-pixels. In case of driving in the power saving mode, the RGB data is converted into a single data and aligned, And a timing controller for outputting the organic EL display device.

Description

[0001] The present invention relates to an organic light emitting diode (OLED) display and a method of driving the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display, and more particularly, to an organic light emitting display and a driving method thereof.

2. Description of the Related Art [0002] As an information-oriented society develops, demands for display devices for displaying images have been increasing in various forms. Recently, organic display devices (LCDs), plasma display panels Various flat display devices such as an organic light emitting diode (OLED) display are utilized.

Of these flat panel display devices, organic light emitting display devices are self-emission type display devices and have recently been widely used because they have advantages of miniaturization, weight reduction, thinning, and low power driving.

Hereinafter, a general OLED display device will be described with reference to FIG.

1 is a block diagram schematically showing a general organic light emitting display device.

As shown in FIG. 1, a general organic light emitting display 10 includes an organic light emitting panel 20 for displaying an image, and a driving unit 60 for driving the organic light emitting panel 20.

A data line DL and a gate line GL intersect each other in the organic luminescent panel 20 to define a sub-pixel SP. The subpixels SP include red (R), green (G), and blue (B) sub-pixels.

The driver 60 includes a data driver 50 for outputting a data voltage to the data line DL and a gate driver 40 for outputting a gate voltage to the gate line GL.

A timing controller 30 for receiving a control signal TCS from the outside and generating a gate control signal GCS for controlling the gate driver 40 and a data control signal DCS for controlling the data driver 50, .

The timing controller 30 receives image data RGB from the outside, arranges the image data RGB, and outputs the image data to the data driver 50.

However, such a general organic light emitting display device 10 drives all the sub-pixels SP even in a simple document editing mode, i.e., a power saving mode, thereby increasing power consumption.

In addition, even though the lifetime of the R, G, and B sub-pixels is different, the R, G, and B sub-pixels are driven in the same manner, which shortens the lifetime of the organic light emitting display. In other words, when the sub-pixel having the shortest lifetime is completely consumed, the organic luminescent panel can no longer be driven even if the sub-pixel having a long lifetime can be driven.

An object of the present invention is to provide an organic light emitting display device and a method of driving the same that can reduce power consumption and extend the life of an organic light emitting panel.

According to an aspect of the present invention, there is provided an organic light emitting diode display comprising: an organic light emitting panel for defining a plurality of subpixels constituting a plurality of pixels by intersecting a plurality of gate lines and a plurality of data lines; In case of driving in the normal mode, the input RGB data is sorted and output to the plurality of sub-pixels. In case of driving in the power saving mode, the RGB data is converted into a single data and aligned, And a timing controller for outputting the organic EL display device.

And a power saving mode signal output unit for outputting a power saving mode signal corresponding to the power saving mode to the timing control unit.

The timing control unit and the power saving mode signal output unit are connected to a switch.

A power saving mode signal is transmitted to the timing controller when the power saving mode is turned on and a mode input is made so that the power saving mode signal is not transmitted to the timing controller by turning off the switch in the normal mode, .

The one pixel has the longest lifetime among the plurality of subpixels.

(A1 * R + a2 * G + a3 * B + a4) / (1 + S) where a1 * R + a2 * G + a3 * B / And a4 are constants, and R, G, and B are R, G, and B component values of the RGB data, and S is 0 or more and 3 or less.

An organic light emitting panel that includes a plurality of gate lines and a plurality of data lines intersecting with each other to define a plurality of subpixels constituting each of a plurality of pixels and a timing controller for driving the organic light emitting panel in a normal mode or a power saving mode, A method of driving an organic light emitting display, the method comprising: arranging input RGB data and outputting the RGB data to the plurality of sub-pixels when driven in the normal mode; And converting the RGB data into a single data and outputting the RGB data to a certain one of the plurality of sub-pixels when driven in the power saving mode.

And outputting a power saving mode signal corresponding to the power saving mode to the timing controller.

The one pixel has the longest lifetime among the plurality of subpixels.

(A1 * R + a2 * G + a3 * B + a4) / (1 + S) where a1 * R + a2 * G + a3 * B / And a4 are constants, and R, G, and B are R, G, and B component values of the RGB data, and S is 0 or more and 3 or less.

The present invention can provide an organic light emitting display device that reduces power consumption and prolongs the life of the organic light emitting panel by converting image data and driving only one subpixel in the power saving mode.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows a general organic light emitting display; FIG.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]
3 is an equivalent circuit diagram for a sub-pixel according to an embodiment of the present invention.
FIG. 4 is a flowchart schematically illustrating an operation of an organic light emitting display according to an exemplary embodiment of the present invention. Referring to FIG.

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

FIG. 2 is a schematic diagram of an organic light emitting display according to an embodiment of the present invention, and FIG. 3 is an equivalent circuit diagram of a sub-pixel according to an embodiment of the present invention.

2, the organic light emitting diode display 100 according to the embodiment of the present invention includes an organic light emitting panel 200 and a driving unit 1000 for driving the organic light emitting panel 200. Referring to FIG.

In the organic luminescent panel 200, a plurality of gate lines GL extend in the first direction, for example, in the horizontal direction. A plurality of data lines DL extend in a second direction intersecting the first direction, for example, in the vertical direction. The plurality of gate lines GL and the plurality of data lines DL intersecting each other define a plurality of sub-pixels SP arranged in a matrix form.

As the sub-pixel SP, for example, R, G, and B sub-pixels that display red, green, and blue may be used. Here, neighboring R, G, and B subpixels constitute a pixel which is a unit of image display.

3, each subpixel SP of the organic light emitting panel 200 includes a switching transistor TS, a driving transistor TD, an organic light emitting diode OD, a capacitor C May be formed.

The switching transistor TS is connected to the corresponding gate wiring and data lines GL and DL. The driving transistor TD is connected to the switching transistor TS. For example, the gate electrode of the driving transistor TD is connected to the drain electrode of the switching transistor TS.

The organic light emitting diode OD is connected to the driving transistor TD. For example, the second electrode of the organic light emitting diode (OD), for example, a cathode is connected to the drain electrode of the driving transistor TD. The first electrode of the organic light emitting diode OD, for example, an anode receives the first driving voltage VDD through the power line PL. An organic light emitting layer including an organic light emitting material that emits light is formed between the first and second electrodes.

The capacitor C is connected between the gate electrode and the source electrode of the driving transistor TD. On the other hand, the source electrode of the driving transistor TD receives the second driving voltage VSS. For example, the source electrode of the driving transistor TD may be grounded.

When the gate line GL is scanned with respect to the subpixel SP having the above structure and a gate signal having a turn-on voltage, for example, a gate high voltage is applied, the switching transistor TS is turned on. As a result, the input data voltage is applied to the gate electrode of the driving transistor TD through the switching transistor TS, so that the current of the first driving voltage VDD passes through the driving transistor TD, OD) to emit light having the corresponding color.

2, the driving unit 1000 for driving the organic light emitting panel 200 includes a timing control unit 300, a gate driving unit 400, a data driving unit 500, a gamma voltage supply unit 600, A power generating unit 700, a mode input unit 800, and a power saving mode signal output unit 900.

The gate driver 400 may sequentially select the gate line GL in response to the gate control signal GCS supplied from the timing controller 300. [ For the selected gate wiring GL, a gate signal having a turn-on voltage is outputted. Thus, the switching transistor TS of the sub-pixel SP connected to the selected gate line GL is turned on. In synchronization with this, the data voltage is outputted to the data line DL and inputted to the corresponding sub-pixel SP.

The data driver 500 generates a data voltage corresponding to the input RGB data RGBD or the single data UD in response to the data control signal DCS supplied from the timing controller 300, And output to the wiring DL. Such a data voltage is generated using the gamma voltages Vgamma. As described above, the data driver 500 converts the image data of the digital format into a data voltage of an analog format and outputs the data.

The gamma voltage supplier 600 divides the high and low potential voltages generated from the power generator 700 to generate a gamma voltage Vgamma and supplies the gamma voltage Vgamma to the data driver 500.

The power generating unit 700 generates various driving voltages required for driving the organic light emitting display 100. For example, a power supply voltage supplied to the timing controller 300, the data driver 500 and the gate driver 400, a gate high voltage and a gate low voltage supplied to the gate driver 400, and the like.

The timing control unit 300 generates and outputs control signals DCS and GCS for controlling the gate driving unit 400 and the data driving unit 500. [ The timing controller 300 also arranges RGB data (RGBD) or converts and arranges RGB data (RGBD), and outputs the RGB data to the data driver 500.

For this purpose, the timing controller 300 may include a control signal generator 310 and a data processor 320.

The control signal generation unit 310 receives the RGB data RGBD, the vertical synchronization signal, the horizontal synchronization signal, the clock signal, and the data enable signal TCS from an external system such as a TV system or a video card . Although not shown, these signals may be input through the interface configured in the timing controller 300. [

The control signal generator 310 generates a data control signal DCS for controlling the data driver 500 and a gate control signal GCS for controlling the gate driver 400 using the input control signal TCS, .

The gate control signal GCS includes a gate start pulse GSP, a gate shift clock GSC and a gate output enable signal GOE. The data control signal DCS includes a source sampling clock (SSC), a source start pulse (SSP), a source output enable (SOE) signal, a polarity signal (POL) . ≪ / RTI >

Here, the gate start pulse is a signal for notifying the first driving line of the organic light emitting panel 200 from one vertical synchronizing signal, and the gate shift clock is generated when the gate of the switching transistor TS is on- And the gate output enable signal is a signal for controlling the output of the gate driver 400. In this case,

The source sampling clock is used as a sampling clock for latching data in the data driver 500 and determines the driving frequency of the data driver 500. [ The source output enable signal transfers the data latched by the source sampling clock to the organic light emitting panel 200. The source start pulse is a signal for notifying the start of data latching or sampling during one horizontal synchronizing period, and the polarity signal is a signal for indicating the polarity for inverting the data voltage.

The data processing unit 320 receives RGB data (RGBD) from an external system, arranges them, and can perform data processing if necessary.

Specifically, when the power saving mode signal SMS is not input to the data processing unit 320, the data processing unit 320 aligns the RGB data RGBD and outputs the sorted RGB data to the data driver 500.

On the other hand, in the power saving mode in which the power saving mode signal SMS is input to the data processing unit 320, the data processing unit 320 converts the RGB data RGBD into single data UD and outputs the single data UD to the data driver 500 .

That is, the data processing unit 320 drives the organic light emitting panel 200 in a normal mode or a power saving mode.

Here, the single data UD is used to input the RGB data RGBD input to each of the R, G and B subpixels SP to the subpixel SP having the longest lifetime, for example, Means that R, G, and B data are combined and converted into one data. Here, the sub-pixel SP having the longest lifetime may be, for example, a G sub-pixel SP.

The power saving mode signal SMS is a signal corresponding to the power saving mode of the driving mode of the data processing unit 320 in order to reduce the power consumption of the organic light emitting display device 100 and extend the life of the organic light emitting panel 200. [

Specifically, the power saving mode is a case in which the power saving mode signal SMS is input to the data processing unit 320. The data processing unit 320 converts the RGB data RGBD into a single data UD output to one sub- And outputs the converted data to the data driver 500.

In addition, the data driver 500 outputs the single data UD to the corresponding data lines DL in response to the data control signal DCS. That is, the single data UD is output to one of the R, G, and B subpixels SP. At this time, the subpixel SP from which the single data UD is output becomes the subpixel SP having the longest lifetime among the R, G, and B subpixels SP.

Hereinafter, an example of a method of converting RGB data (RGBD) into single data UD will be described.

First of all, there are a RGB system and a YCbCr (YUV) system.

The RGB method is a method of expressing colors using the three primary colors of light (red, green, and blue). Generally, it is used for the color representation of TV, monitor, and HTML. Since the computer monitor uses the RGB method, in order to transmit the image to the display device, it has to be converted into the RGB method. Each of R (red), G (green) and B (blue) values has a tone value (8 bits) ranging from 0 to 255, for example. Accordingly, the image is, for example, R, G, and B, each having 8 bits, totaling 24 bits.

The YCbCr (YUV) method is a method of expressing colors using Y representing luminance and Cb and Cr representing chroma. This rendering method has a merit that color separation and transmission effect is weaker than RGB method, but more colors can be represented with less data.

The reason for using the YCbCr method is that a person recognizes an object and is sensitive to luminance but other color components are not very sensitive. Therefore, compared to the RGB method in which all color information that is not sensitive to human beings must be included, it is possible to display a similar image quality with a small amount of data (about 1/2).

Here, in the embodiment of the present invention, the RGB component (RGBD) input by the RGB method is converted into the YUV method to detect the luminance component.

Specifically, the data processing unit 320 obtains the luminance component Y of the RGB data RGBD input from the external system.

Here, the luminance component (Y) is obtained by equation (1) or (2).

(1): Y = a1 * R + a2 * G + a3 * B

(2): Y = a1 * R + a2 * G + a3 * B + a4

Here, a1 to a3 are constants, and R, G, and B are R, G, and B component values of RGB data (RGBD). On the other hand, a1 to a4 may have values of, for example, a1 = 0.299, a2 = 0.587, and a3 = 0.114, respectively.

The luminance component Y thus obtained is divided by the value of (1 + S). That is, the single data UD is obtained by the equation (2).

(2): Single data (UD) = (a1 * R + a2 * G + a3 * B) / (1 + S)

Here, S is a value for adjusting the level of the luminance component (Y) of the RGB data (RGBD). Specifically, for example, when S is 0, the original luminance component (Y) becomes the single data (UD). When S is 1, the luminance that is 1/2 of the original luminance component (Y) (UD).

In another embodiment, the luminance component may be obtained by adding all of the R, G, and B component values and dividing by 3, that is, the average value of the R, G, and B data.

As described above, when the power saving mode signal SMS is not inputted to the data processing unit 320, the RGB data RGBD is sorted and outputted to the data driver 500. [

On the other hand, when the power saving mode signal SMS is input to the data processing unit 320, the data processing unit 320 converts the RGB data RGBD into a single data UD, And outputs the single data (UD) to the data driver (500).

At this time, the data value of the remaining sub-pixels SP in which the single data UD is not output may be zero. For example, when the RGB data (RGBD) is converted into YUV data or when the R, G, and B component values are all added and divided by 3, the remaining two sub-pixels SP May be zero.

The power saving mode signal output unit 900 is connected to the timing control unit 300 through a switch SW and outputs the power saving mode signal SMS to the timing control unit 300. [

At this time, when the switch SW is turned on, the power saving mode signal SMS is transmitted to the timing controller 300, and when the switch SW is turned off, the transmission of the power saving mode signal SMS is stopped.

As described above, the power saving mode signal SMS is a signal that allows the timing controller 300 to operate in the power saving mode in order to reduce current consumption and the like of the organic light emitting diode display 100.

The mode input unit 800 turns on or off the switch SW connected between the timing control unit 300 and the power saving mode signal output unit 900.

For example, when a viewer inputs a signal corresponding to the power saving mode, that is, a signal corresponding to the power saving mode, the mode input unit 800 turns on the switch.

On the other hand, when the viewer inputs a signal corresponding to the normal mode, not the power save mode, the mode input unit 800 turns off the switch.

That is, when the organic light emitting diode display 100 is driven in the power saving mode, the mode input unit 800 turns on the switch so that the power saving mode signal SMS is transmitted from the power saving mode signal output unit 900 to the timing controller 300 To be delivered.

On the other hand, when the organic light emitting diode display 100 is driven in the normal mode, the mode input unit 800 turns off the switch so that the power saving mode signal SMS is transmitted from the power saving mode signal output unit 900 to the timing controller 300 Do not transmit.

Hereinafter, the operation of the OLED display 100 according to the embodiment of the present invention will be described with reference to FIG.

4 is a flow chart showing an operational flow of the OLED display 100 according to the embodiment of the present invention.

First, it is determined whether the operation of the OLED display 100 is driven in a power saving mode (S1). This is determined, for example, according to whether the signal is inputted from the outside. When the power saving mode signal is input from the outside, the organic light emitting display 100 is operated in the power saving mode, and when the normal mode signal is inputted from the outside, Is operated.

First, when a signal corresponding to the power saving mode is input from the outside, that is, when the OLED display 100 is driven in the power saving mode, the mode input unit 800 turns on the switch SW (S21).

Accordingly, the power saving mode signal SMS is transmitted from the power saving mode signal output unit 900 to the data processing unit 320 (S31).

Accordingly, the data processing unit 320 converts the RGB data RGBD into a single data UD, and transmits the single data UD to the data driver 500 (S41).

On the other hand, when the OLED display 100 is driven in the normal mode, that is, when a signal corresponding to the normal mode is inputted from the outside, the mode input unit 800 turns off the switch SW (S22).

Accordingly, the power saving mode signal SMS can not be transmitted to the data processing unit 320 (S32).

Accordingly, the data processing unit 320 aligns RGB data (RGBD) and transmits the RGB data to the data driver 500 (S42).

As described above, in the embodiment of the present invention, when the organic light emitting diode display 100 operates in the power saving mode, RGB data is converted into single data and output to a single sub-pixel.

In an embodiment of the present invention, a single data may be output to the G subpixel, for example. This is because the G subpixel has the longest luminous efficiency and lifetime among the R, G, and B sub-pixels, and consumes the smallest current.

That is, it is possible to output a single data to the most efficient sub-pixel corresponding to the characteristics of the R, G, and B sub-pixels.

Accordingly, the current consumption of the OLED display device can be reduced, and the life of the OLED display device can be prolonged.

The embodiment of the present invention described above is an example of the present invention, and variations are possible within the spirit of the present invention. Accordingly, the invention includes modifications of the invention within the scope of the appended claims and equivalents thereof.

300: timing controller 310: control signal generator 320: data processor
400: Gate driver 500: Data driver
800: Mode input unit 900: Power saving mode signal output unit
SMS: Power-saving mode signal RGBD: RGB data UD: Single data

Claims (10)

An organic light emitting panel defining R, G, and B subpixels, each of which includes a plurality of gate lines and a plurality of data lines intersecting with each other to form a plurality of pixels;
In case of driving in the normal mode, the input RGB data are aligned and output to the R, G, and B sub-pixels,
And a timing controller for converting the RGB data into a single data and outputting the data to only one of the R, G, and B sub-pixels when driven in a power saving mode
Organic light emitting display.
The method according to claim 1,
And a power saving mode signal output unit for outputting a power saving mode signal corresponding to the power saving mode to the timing control unit
Organic light emitting display.
3. The method of claim 2,
The timing control unit and the power saving mode signal output unit are connected to a switch
Organic light emitting display.
The method of claim 3,
When the power saving mode is selected, the switch is turned on to cause the power saving mode signal to be transmitted to the timing controller,
And a mode input unit for turning off the switch in the normal mode so that the power saving mode signal is not transmitted to the timing control unit
Organic light emitting display.
The method according to claim 1,
The one subpixel has the longest lifetime among the R, G, and B subpixels
Organic light emitting display.
The method according to claim 1,
The formula for obtaining the single data is (a1 * R + a2 * G + a3 * B) / (1 + S) or (a1 * R + a2 * G + a3 * B + a4) /
a1 to a4 are constants, R, G, and B are R, G, and B component values of the RGB data,
S is 0 or more and 3 or less
Organic light emitting display.
An organic light emitting panel for defining R, G and B sub-pixels constituting each of a plurality of pixels by intersecting a plurality of gate wirings and a plurality of data wirings; a timing controller for driving the organic light emitting panel in a normal mode or a power save mode; The method of driving an organic light emitting display device according to claim 1,
Arranging the input RGB data and outputting the RGB data to the R, G, and B sub-pixels when driven in the normal mode;
And converting the RGB data into a single data and outputting the RGB data to only one of the R, G, and B sub-pixels when driven in the power saving mode
A method of driving an organic light emitting display device.
8. The method of claim 7,
And outputting a power saving mode signal corresponding to the power saving mode to the timing control unit
A method of driving an organic light emitting display device.
8. The method of claim 7,
The one subpixel has the longest lifetime among the R, G, and B subpixels
A method of driving an organic light emitting display device.
8. The method of claim 7,
The formula for obtaining the single data is (a1 * R + a2 * G + a3 * B) / (1 + S) or (a1 * R + a2 * G + a3 * B + a4) /
a1 to a4 are constants, R, G, and B are R, G, and B component values of the RGB data,
S is 0 or more and 3 or less
A method of driving an organic light emitting display device.

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