KR20190051411A - Organic light emitting display device - Google Patents

Abstract

The present invention relates to an organic light emitting display device capable of removing dimming phenomena caused by inserting black data which comprises: a pixel unit having a plurality of pixels formed by crossing a plurality of gate lines and a plurality of data lines; a gate driver for driving the gate lines; a data driver for driving the data lines; a black data insertion unit for providing the pixel unit with black data which is inserted into a period during which data signals output from the data drive are applied; and a timing control unit for controlling a driving clock of the gate driver for determining a time when the black data output through the black data insertion unit is applied and removing dimming phenomena which may occur by simultaneously inserting the black data in n line units.

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to an organic light emitting diode (OLED) display, and more particularly, to an OLED display capable of eliminating a lateral dimming phenomenon caused by black data insertion.

2. Description of the Related Art Recently, various flat panel display devices capable of reducing weight and volume, which are disadvantages of cathode ray tubes (CRTs), have been developed. Examples of the flat panel display include a liquid crystal display, a field emission display, a plasma display panel, and an organic light emitting display. In particular, an OLED displays an image using an organic light emitting diode that emits light by recombination of electrons and holes. Such an organic light emitting display device is advantageous in that it has a fast response speed and is driven with low power consumption.

Since the organic electroluminescent display device is driven in a hold type, the time-frequency characteristic of the light for displaying the moving picture is low, and the spatial frequency characteristic is lowered thereby causing blurring of the moving picture.

This is due to the integration effect of the image which is temporally continuous in the eye following the movement. Due to the nature of the hold-type scheme, the organic light emitting display device has a problem in that, due to mismatch between the eye movement and the static image of each frame, Will see a blurry picture. That is, the hold-type organic light emitting display device has a drawback that the MPRT index is lower than that of the impulse type CRT.

In order to overcome this disadvantage, a "black insertion" scheme has been studied in which each image is displayed in one frame, and then the entire screen is converted into a black display by inserting black data before the next frame is displayed .

However, in the related art, such a black data is generated and a new driving circuit or a new driving method is studied in order to provide the black data to the pixel portion. In this case, however, the circuit may become complicated.

An object of the present invention is to improve the image quality of an organic light emitting display device.

It is another object of the present invention to provide an organic light emitting display capable of eliminating the occurrence of a lateral dimming phenomenon that may occur when inserting black data.

According to an aspect of the present invention, there is provided an organic light emitting display including: a pixel portion including a plurality of pixels formed by intersection of a plurality of gate lines and a plurality of data lines; A gate driver for driving the plurality of gate lines; A data driver for driving the plurality of data lines; A black data insertion unit for providing black data inserted between the data signals outputted from the data drive unit to the pixel unit; And a timing controller for controlling the driving clock of the gate driver for determining the time at which the black data outputted through the black data inserting unit is applied to eliminate the dimming phenomenon that may occur due to the simultaneous insertion of the black data in units of n lines The present invention has been made in view of the above problems.

The timing control unit of the organic light emitting diode display according to the present invention may be configured such that a pulse width for inserting black data included in a driving clock supplied to a part of gate lines of every frame among driving clocks provided to the gate driver is supplied to another gate line And output differently from the pulse width for black data insertion of the clock.

The timing controller of the organic light emitting diode display according to the present invention changes the pulse width for inserting the black data among the driving clocks of the first line of each frame in units of n data lines in which black data is concurrently inserted to eliminate the dimming phenomenon .

The timing control unit of the OLED display according to the present invention outputs a pulse width for inserting black data among the first driving clock of each frame to half of a pulse width for inserting black data of a driving clock for supplying to other gate lines, Eliminating the phenomenon.

The timing controller of the organic light emitting display according to the present invention controls the gate line in which the dimming phenomenon occurs to be shifted frame by frame.

The timing controller of the organic light emitting diode display according to the present invention controls the gate line driving clock so that the driving sequence of the gates is reversed for each frame in units of n (n is a positive integer) And sequentially drives in the reverse order from the n-th line in the even-numbered frame.

The timing controller of the organic light emitting display according to the present invention drives the gates alternately in units of n (n is a positive integer) line by frame.

In the organic light emitting diode display according to the present invention, the number of repetitions of the clock signal is equal to the number of n lines simultaneously receiving the black data, and the order in which the clock signal is generated is randomly output for n frames.

The effects of the OLED display according to the present invention are as follows.

First, the image quality of the organic light emitting display device is improved.

Second, it is possible to eliminate the occurrence of the lateral dimming phenomenon.

1 is a schematic block diagram of an organic light emitting display according to the present invention.
FIG. 2A is an example of a hold-type display method, and FIG. 2B is an example of an impulse display method.
3 is a diagram illustrating a technique for inserting black data in an OLED display according to an embodiment of the present invention.
4 is a diagram illustrating an example of a gate driving waveform according to an OLED display according to a first embodiment of the present invention.
FIG. 5 is a diagram illustrating waveforms of gate driving according to an organic light emitting display according to a second embodiment of the present invention. Referring to FIG.
6A and 6B are diagrams illustrating waveforms of gate driving according to an organic light emitting display according to a third embodiment of the present invention.
7 is a view illustrating another example of a waveform of a gate driving according to the organic light emitting display according to the third embodiment of the present invention.

For specific embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be embodied in various forms, And should not be construed as limited to the embodiments described.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is susceptible of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms " comprises ", or " having ", and the like, are intended to specify the presence of stated features, integers, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be construed to indicate meaning consistent with the meaning of the context in the relevant art and are to be construed as either ideal or overly formal in meaning unless expressly defined in the present application Do not.

On the other hand, if an embodiment is otherwise feasible, the functions or operations specified in a particular block may occur differently than the order specified in the flowchart. For example, two consecutive blocks may actually be performed at substantially the same time, and depending on the associated function or operation, the blocks may be performed backwards.

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

1 is a schematic block diagram of an organic light emitting display according to an embodiment of the present invention. 1, an OLED display according to an exemplary embodiment of the present invention includes a pixel portion (pixel portion) including a plurality of pixels 40 connected to scan lines S1 to Sn and data lines D1 to Dm A gate driver 10 for driving the scan lines S1 to Sn and a data driver 20 for driving the data lines D1 to Dm; A black data inserter 60 provided between the data driver 20 and the data driver 20 to provide black data to the pixel unit 30 during a period in which the data signals are applied; A timing controller 50 for controlling a driving clock of the gate driver that determines the time for which black data to be output through the black data inserter is applied to eliminate a dimming phenomenon that may be caused by simultaneously inserting black data in units of n lines; .

The timing controller 50 controls the operation of the data control signal DCS, the scan control signal SCS and the black data inserter 60 according to the synchronization signals supplied from the outside And generates an enable signal (Enable signal) to be controlled.

That is, the data driving control signal DCS generated by the timing controller 50 is supplied to the data driver 20, the scan driving control signal SCS is supplied to the gate driver 10, And is supplied to the inserting portion 60. The timing controller 50 supplies data (Data) supplied from the outside to the data driver 20.

The gate driver 10 receives the scan driving control signal SCS from the timing controller 50 and generates a scan signal and sequentially supplies the generated scan signal to the scan lines S1 to Sn.

The data driver 20 receives the data driving control signal DCS from the timing controller 50 and generates a data signal and supplies the generated data signal to the data lines D1 to Dm in synchronization with the scan signal . That is, the output channels O1 to Om of the data driver 20 are connected to the data lines D1 to Dm, respectively.

The pixel unit 30 receives the first power ELVDD and the second power ELVSS from the outside and supplies the power to the respective pixels 40. [ Each of the pixels 40 supplied with the first power ELVDD and the second power ELVSS receives a current flowing from the first power ELVDD through the light emitting element to the second power ELVSS Thereby generating light corresponding to the data signal. At this time, the first power ELVDD has a voltage level higher than the second power ELVSS.

2A shows an image display state of a display device driven in a hold-type manner. That is, during the scan period in which the scan signals are sequentially supplied to the scan lines, data is supplied to each of the pixels constituting the pixel portion, and data supplied to the pixels are maintained during the non- .

A new display method has been proposed to prevent motion blurring in a display device driven in a hold-type manner. And the display device is driven in an impulse manner like the image change shown in FIG. 2B. As shown in FIG. 3, black data is inserted between each image frame. A new data enable signal DE_new is generated by further including one driving clock in the data enable signal DE to be input and the black data B is inserted into the data signal Data.

The present invention is based on a technique for sequentially opening a gate drive and a technique for displaying black data in a data signal provided through a data line by simultaneously opening a plurality of gates for black data insertion.

The following waveform diagram shows only eight gate line driving clocks at the same time in which pulses for black data insertion are simultaneously displayed on four gate lines to explain the operation of the present invention.

4 is a diagram illustrating an example of a gate driving waveform according to an OLED display according to a first embodiment of the present invention.

In the organic light emitting diode display according to the present invention, the timing controller may supply a pulse width for inserting black data included in a driving clock supplied to some gate lines of every frame among the driving clocks supplied to the gate driver to another gate line So that the output is different from the pulse width for inserting the black data of the clock. In the first embodiment, a pulse for inserting black data appears simultaneously on four gate lines at the same time, but black data can be simultaneously inserted into n (n is a positive integer) gate lines . In the first embodiment, the technical features of the first embodiment are applied to every four gate lines, and the present invention is not limited to the number of gate lines into which black data is simultaneously inserted.

That is, the timing control unit in the organic light emitting display according to the first exemplary embodiment has a pulse width for inserting black data among the driving clocks of the first gate lines of each frame in units of four gate driving lines simultaneously injecting black data Respectively.

Preferably, the pulse width for inserting black data from the first drive clock (CLK1 to CLK3) excluding the first drive clock (CLK0) of each frame is " T ", and the black data insertion of the first drive clock The pulse width is " T / 2 ". That is, by halving the pulse width for black data insertion, it is possible to eliminate the lateral dimming phenomenon caused by the image data in which the gate is opened by the first driving clock of the next frame. In the present embodiment, since black data is simultaneously inserted into four gate lines, the width of the pulse for inserting black data of the fifth gate drive clock signal CLK4 is " T / 2 " The same applies to the gate drive clocks CLK8 and CLK12 of the four gate drive lines. This operation is also applied to every frame. Therefore, it is possible to eliminate the horizontal dimming phenomenon caused by the black data insertion in the entire screen.

As another embodiment of the present invention, the timing control unit controls the gate line in which the dimming phenomenon occurs to be shifted in units of frames. In other words, in the first embodiment, the same technique is applied to all frames, whereas in the following second and third embodiments, technical features can be applied frame by frame.

FIG. 5 is a diagram illustrating waveforms of gate driving according to an organic light emitting display according to a second embodiment of the present invention. Referring to FIG. As shown in FIG. 4, the timing control unit controls the gate driving clocks so that the driving sequence of the gates is reversed for each frame in units of four scan lines for simultaneously inserting the black data into the image data provided to the pixel unit To sequentially drive in the reverse order from the fourth line in the even-numbered frames.

In other words, when a pulse for inserting black data is outputted simultaneously to four gate lines, a driving clock is sequentially supplied to each gate line. In the first frame (1st frame), the driving clock of the first gate line A pulse for inserting black data is simultaneously output to the driving clock CLK3 of the fourth gate line from the first driving clock CLK0 to the driving clock CLK3 of the fourth gate line and a pulse for inserting black data is simultaneously output from the fifth driving clock CLK4 to the eighth driving clock CLK7 do.

In the second frame, however, the gate of the corresponding gate line is opened since CLK2, CLK1, and CLK0 are sequentially provided in the reverse order from the driving clock CLK3 of the fourth gate line. Of course, this operation is performed in the order of CLK6, CLK5, and CLK4 in the reverse order from the drive clock CLK7 of the eighth gate line in the following gate lines, so that the gate of the corresponding gate line is opened.

On the other hand, the driving operation for sequentially opening the gate in the reverse order is implemented in each even-numbered frame, and the gate driving in the third frame is performed in the same manner as the first frame.

The timing control unit according to the second embodiment of the present invention controls the gate driving sequence to alternate with the period of the four gate lines per frame. Therefore, since the horizontal dimming occurs alternately in frame units, the horizontal dimming phenomenon can not be perceived in terms of cognition. In this second embodiment as well, the number of gate lines for simultaneously opening the gate for black data insertion is variable, and the present invention is not limited thereto.

6A and 6B are diagrams illustrating waveforms of gate driving according to an organic light emitting display according to a third embodiment of the present invention. That is, similar to the second embodiment, a technique for controlling a driving clock provided to a gate line in units of frames to eliminate horizontal dimming caused by black data insertion.

The timing control unit controls the cycle in which the clock signal is repeated to be equal to the number of n lines in which the black data is simultaneously received, and the order in which the clock signal is generated is randomly output differently for n frames.

For example, as shown in FIG. 6A, when black data is simultaneously inserted in units of four gate lines at the same time, black data is inserted while the gates are sequentially opened in the first frame.

In the second frame, the driving clocks (CLK3 and CLK7) are outputted so that the gates of the fourth gate line and the eighth gate line are opened first. Thereafter, the gate is opened by (CLK0, CLK1, CLK2) and (CLK4, CLK5, CLK6).

On the other hand, in the third frame, the driving clocks CLK2 and CLK6 are outputted so that the gates of the third gate line and the seventh gate line are opened first. Thereafter, the gate is opened by the driving clocks (CLK3, CLK0, CLK1) and (CLK7, CLK4, CLK5).

As shown in FIG. 6B, in the fourth frame, the driving clocks CLK1 and CLK5 are outputted so that the gates of the second gate line and the sixth gate line are opened first. Thereafter, the gates are opened by the driving clocks (CLK2, CLK3, CLK0) and (CLK6, CLK7, CLK4).

The gate line drive clocks in the fifth frame and the sixth frame are also output in the same manner as the gate line drive clocks in the first frame and the second frame in FIG. 6A. That is, in the third embodiment of the present invention, when simultaneously inserting black data in units of n gate lines, the driving clock provided to the gate line is controlled in units of n frames, and the horizontal dimming Can be removed. In the third embodiment, the gate of the pixel connected to the corresponding gate line is opened by the fourth driving clock CLK3 and the eighth driving clock CLK7 in the second frame. However, as shown in FIG. 7, The gate of the pixel connected to the gate line is opened first by the third drive clock signal CLK2 and the seventh drive clock signal CLK6 in the second frame and the fourth drive clock signal CLK3 and the eighth drive clock signal The gate of the pixel connected to the gate line may be opened first by the gate line CLK7. As described above, by randomly driving the order in which the gates are opened first in units of n frames, it is possible to eliminate the horizontal dimming phenomenon caused by the continuous occurrence of the dimming phenomenon caused by the black data insertion in each frame in the same gate line As a result, the image quality of the organic light emitting display device is improved.

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 present invention as defined by the following claims It can be understood that

10: gate driver 20: data driver
30: pixel unit 40: pixel
50: timing control section 60: black data insertion section

Claims (8)

A pixel portion in which a plurality of pixels are formed by intersection of a plurality of gate lines and a plurality of data lines;
A gate driver for driving the plurality of gate lines;
A data driver for driving the plurality of data lines;
A black data insertion unit for providing black data inserted between the data signals outputted from the data drive unit to the pixel unit;
And a timing controller for controlling the driving clock of the gate driver to determine the time at which the black data outputted through the black data inserting unit is applied to remove the dimming phenomenon that may occur due to the simultaneous insertion of the black data in units of n lines And the organic light emitting display device. The method according to claim 1, wherein the timing control unit controls the timing of the driving clock supplied to the other gate lines so that the pulse width for inserting black data included in the driving clock supplied to the gate line of each frame among the driving clocks provided to the gate driver And outputting a pulse width different from a pulse width for black data insertion. 3. The organic light emitting display according to claim 2, wherein the timing control unit varies the pulse width for inserting the black data among the driving clocks of the first line of each frame in units of n gate lines in which black data is concurrently inserted at the same time, Device. The plasma display apparatus of claim 3, wherein the timing controller outputs a pulse width for inserting black data among the first driving clock of every frame to a half of a pulse width for inserting black data of a driving clock for supplying to other gate lines To the organic light emitting display device. The organic light emitting diode display according to claim 1, wherein the timing controller controls the gate line in which the dimming phenomenon occurs to be shifted frame by frame. The method of claim 5, wherein the timing controller controls the gate line driving clock so that the gate driving sequence is reversed for each frame in units of n gate lines simultaneously inserted with black data, Type organic light emitting display device according to the present invention. The organic light emitting diode display according to claim 6, wherein the timing control unit alternately drives a gate driving sequence for each frame in units of n (n is a positive integer) line. 6. The organic light emitting display according to claim 5, wherein the period in which the clock signal is repeated is equal to the number of n lines in which the black data are simultaneously received, and the order in which the clock signal is generated is randomly output for n frames. Device.

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