KR100836430B1 - Organic light emitting display device - Google Patents

Abstract

An OLED device is provided to display images uniformly regardless of lifetime characteristics of an organic light emitting diode by setting capacitance of a second capacitor corresponding to lifetime characteristics of R,G,B organic light emitting diodes. An OLED(Organic Light Emitting Display) device includes a data driver(120), a scan driver(110) and R,G,B pixels(140). The data driver supplies data signals to data lines. The scan driver sequentially supplies low level scan signals to scan lines and high level light emitting control signals to light emitting control lines. The R,G,B pixels are positioned to connect with scan and data lines. Each of the R,G,B pixels includes an organic light emitting diode, a second transistor, and first and second capacitors. The second transistor supplies the current from a first voltage source to a second voltage source through the organic light emitting diode. The first capacitor is connected between a gate of the second transistor and the first voltage source. The second capacitor whose capacitance is differently set at the R,G,B pixels, is connected between the gate of the second transistor and the second voltage source.

Description

Organic Light Emitting Display Device

1 is a circuit diagram showing a conventional pixel.

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

3 is a circuit diagram illustrating a pixel according to an exemplary embodiment of the present invention.

4 is a waveform diagram illustrating a method of driving the pixel of FIG. 3.

5 is a circuit diagram illustrating a pixel according to another exemplary embodiment of the present invention.

6 is a waveform diagram illustrating a method of driving the pixel of FIG. 5.

<Explanation of symbols for main parts of the drawings>

2,142,142R, 142G, 142B: Pixel Circuit 4,140,140R, 140G, 140B: Pixel

110: scan driver 120: data driver

130: pixel portion 150: timing controller

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device capable of compensating for deterioration of image quality over time.

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, and an organic light emitting display.

Among flat panel displays, an organic light emitting display device displays an image using an organic light emitting diode that generates light by recombination of electrons and holes. Such an organic light emitting display device has an advantage of having a fast response speed and being driven with low power consumption.

1 is a circuit diagram illustrating a pixel of a conventional organic light emitting display device.

Referring to FIG. 1, a pixel 4 of a conventional organic light emitting display device is connected to an organic light emitting diode OLED, a data line Dm, and a scanning line Sn to control the organic light emitting diode OLED. The pixel circuit 2 is provided.

The anode electrode of the organic light emitting diode OLED is connected to the pixel circuit 2, and the cathode electrode is connected to the second power source ELVSS. Such an organic light emitting diode (OLED) generates light having a predetermined brightness in response to a current supplied from the pixel circuit 2.

The pixel circuit 2 controls the amount of current supplied to the organic light emitting diode OLED corresponding to the data signal supplied to the data line Dm when the scan signal is supplied to the scan line Sn. To this end, the pixel circuit 2 includes a second transistor M2 connected between the first power supply ELVDD and the organic light emitting diode OLED, the second transistor M2, the data line Dm, and the scan line Sn. And a first capacitor M1 connected between the first transistor M1 and a storage capacitor Cst connected between the gate electrode and the first electrode of the second transistor M2.

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 terminal of the storage capacitor Cst. 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. For example, when the first electrode is set as the source electrode, the second electrode is set as the drain electrode. The first transistor M1 connected to the scan line Sn and the data line Dm is turned on when a scan signal is supplied from the scan line Sn to receive a data signal supplied from the data line Dm to the storage capacitor Cst. ). In this case, the storage capacitor Cst charges a voltage corresponding to the data signal.

The gate electrode of the second transistor M2 is connected to one terminal of the storage capacitor Cst, and the first electrode is connected to the other terminal of the storage capacitor Cst and the first power supply ELVDD. The second electrode of the second transistor M2 is connected to the anode electrode of the organic light emitting diode OLED. The second transistor M2 controls the amount of current flowing from the first power source ELVDD to the second power source ELVSS via the organic light emitting diode OLED in response to the voltage value stored in the storage capacitor Cst. In this case, the organic light emitting diode OLED generates light corresponding to the amount of current supplied from the second transistor M2.

Such an organic light emitting display device is divided into a red pixel, a green pixel, and a blue pixel corresponding to a color to be displayed. The red pixel includes a red organic light emitting diode to generate red light, and the green pixel includes a green organic light emitting diode to generate green light. The blue pixel includes a blue organic light emitting diode to produce blue light.

Here, the red organic light emitting diode, the green organic light emitting diode, and the blue organic light emitting diode are formed of different materials, and thus have different lifetime characteristics. In fact, conventionally used organic light emitting diodes have lifespan characteristics such as Equation 1 depending on the material properties.

OLED (B) <OLED (R) <OLED (G)

In Equation 1, OLED (B) represents a blue organic light emitting diode, OLED (R) represents a red organic light emitting diode, and OLED (G) represents a green organic light emitting diode.

Referring to Equation 1, the lifetime characteristics of the blue organic light emitting diode are shortest, and the lifetime characteristics of the green organic light emitting diode are set longest. In this case, the quality of the organic light emitting display device is deteriorated due to the organic light emitting diode having different lifetime characteristics over time. For example, over time, white balance may deteriorate or image sticking may be severe.

Accordingly, an object of the present invention is to provide an organic light emitting display device which can compensate for a deterioration in image quality over time.

In order to achieve the above object, an organic light emitting display device according to an embodiment of the present invention includes a data driver for supplying a data signal to the data lines; A scan driver for sequentially supplying low-level scan signals to the scan lines and sequentially supplying high-level emission control signals to the emission control lines; Red pixels, green pixels, and blue pixels positioned to be connected to the scanning lines and the data lines; Each of the red, green, and blue pixels includes an organic light emitting diode; A second transistor for supplying a current from a first power supply to a second power supply via the organic light emitting diode; A first capacitor connected between the gate electrode of the second transistor and the first power source; A second capacitor connected between the gate electrode and the second electrode of the second transistor; The capacitance of the second capacitor is set differently in the red pixel, the green pixel, and the blue pixel.

Preferably, the second capacitor is set to have a higher capacitance as the lifespan of the organic light emitting diode included in each of the red, green, and blue pixels is longer. The capacitance of the second capacitor included in the green pixel is set highest, and the capacitance of the second capacitor included in the blue pixel is set lowest.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 2 to 6 that can be easily implemented by those skilled in the art.

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

Referring to FIG. 2, an organic light emitting display device according to an exemplary embodiment of the present invention includes pixels positioned to be connected to scan lines S1 to Sn, emission control lines E1 to En, and data lines D1 to Dm. Driving the pixel unit 130 including the 140, the scan driver 110 for driving the scan lines S1 to Sn and the emission control lines E1 to En, and the data lines D1 to Dm. And a timing controller 150 for controlling the data driver 120 and the scan driver 110 and 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 generates a scan signal and sequentially supplies the generated scan signal to the scan lines S1 to Sn. In addition, the scan driver 110 generates an emission control signal in response to the scan driving control signal SCS, and sequentially supplies the generated emission control signal to the emission control lines E1 to En. Here, the width of the light emission control signal is set to the same or wider width than the scan signal. For example, the width of the light emission control signal supplied to the i (i is a natural number) light emission control line is set so as to overlap the scan signal supplied to the i-th scan line. In addition, the width of the light emission control signal supplied to the i-th light emission control line may be set so as to overlap with the i-1th scan line and the scan signal supplied to the i-th scan line.

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 in synchronization with the scan signal.

The timing controller 150 generates a data drive control signal DCS and a scan drive control signal SCS in response to external synchronization signals. 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 pixel unit 130 receives the first power source ELVDD and the second power source ELVSS from the outside and supplies the same to the pixels 140. Each of the pixels 140 supplied with the first power source ELVDD and the second power source ELVSS generates light corresponding to the data signal. Here, the emission time of the pixels 140 is controlled by the emission control signal. On the other hand, the first power source ELVDD is set to a higher voltage value than the second power source ELVSS.

The pixels 140 included in the pixel unit 130 are divided into a red pixel, a green pixel, and a blue pixel corresponding to the color to be displayed. The red pixel has a red organic light emitting diode for displaying red color, and the green pixel has a green organic light emitting diode for displaying green color. The blue pixel includes a blue organic light emitting diode to display blue.

3 is a circuit diagram illustrating a red pixel, a green pixel, and a blue pixel illustrated in FIG. 2.

Referring to FIG. 3, the circuit structures of the red pixel 140R, the green pixel 140G, and the blue pixel 140B are set identically. Therefore, the structure of the pixel will be described based on the red pixel 140R.

The red pixel 140R is connected to the organic light emitting diode OLED (R), the data line Dm-2, and the scan line Sn to control the organic light emitting diode OLED (R). It is provided.

The anode electrode of the organic light emitting diode OLED (R) is connected to the pixel circuit 142R, and the cathode electrode is connected to the second power source ELVSS. The organic light emitting diode OLED (R) generates light having a predetermined luminance in response to a current supplied from the pixel circuit 142R.

The pixel circuit 142R controls the amount of current supplied to the organic light emitting diode OLED (R) corresponding to the data signal supplied to the data line Dm-2 when the scan signal is supplied to the scan line Sn. To this end, the pixel circuit 142R includes a second transistor M2 and a third transistor M3 and a second transistor M2 connected between the first power supply ELVDD and the organic light emitting diode OLED (R). A first transistor M1 connected between the data line Dm-2 and the scan line Sn, a first capacitor C1 connected between the gate electrode and the first electrode of the second transistor M2, A second capacitor C2 is connected between the gate electrode and the second electrode of the second transistor M2.

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-2. The second electrode of the first transistor M1 is connected to the gate electrode of the second transistor M2. The first transistor M1 connected to the scan line Sn and the data line Dm-2 is turned on when the scan signal is supplied to the scan line Sn to receive a data signal supplied from the data line Dm-2. Supply to the first capacitor C1.

The gate electrode of the second transistor M2 is connected to the second electrode of the first transistor M1, 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 source ELVDD to the organic light emitting diode OLED (R) in response to the voltage applied to its gate electrode.

The first electrode of the third transistor M3 is connected to the second electrode of the second transistor M2, and the second electrode is connected to the anode electrode of the organic light emitting diode OLED (R). The gate electrode of the third transistor M3 is connected to the emission control line En. The third transistor M3 controls the supply time of the current supplied to the organic light emitting diode OLED (R) and the supply time of the current in response to the emission control signal supplied from the emission control line En.

The first capacitor C1 is formed between the gate electrode of the second transistor M2 and the first power source ELVDD. The first capacitor C1 charges a voltage corresponding to the data signal when the data signal is supplied.

The second capacitor C2 is positioned between the gate electrode and the second electrode of the second transistor M2. The second capacitor C2 transfers the voltage change amount of the second electrode of the second transistor M2 to the gate electrode of the second transistor M2.

Meanwhile, in the present invention, the capacitances of the second capacitor C2 included in the red pixel 140R, the green pixel 140G, and the blue pixel 140B are set differently from each other. In practice, the second capacitor C2 has a lifetime such that the lifetime characteristics of the red organic light emitting diode OLED (R), the green organic light emitting diode OLED (G) and the blue organic light emitting diode OLED (B) can be compensated for. The capacity is set. For example, the capacity of the second capacitor C2 may be set as in Equation 2.

C2 (B) <C2 (R) <C2 (G)

In Equation 2, C2 (B) is the second capacitor C2 included in the blue pixel 140B, C2 (R) is the second capacitor C2 included in the red pixel 140R, and C2 (G) is green. The second capacitor C2 included in the pixel 140G is shown.

Referring to Equation 2, the capacitance of the second capacitor C2 included in the pixel having the short lifespan characteristic (ie, the blue pixel 140B) is set to be the smallest, and the pixel having the long lifespan characteristic (ie, the green pixel ( 140G)) sets the capacity of the second capacitor C2 included in the longest. As such, when the capacitance of the second capacitor C2 is set, the lifespan characteristics of the red organic light emitting diode OLED (R), the green organic light emitting diode OLED (G), and the blue organic light emitting diode OLED (B) are determined. It can compensate for the deterioration of image quality. Detailed description thereof will be described later.

4 is a diagram illustrating a driving waveform supplied to the pixels shown in FIG. 3.

3 and 4, the operation process will be described in detail. First, the emission control signal is supplied to the emission control line En. When the emission control signal is supplied, the third transistor M3 included in each of the red pixel 140R, the green pixel 140G, and the blue pixel 140B is turned off. After the third transistor M3 is turned off, the scan signal is supplied to the scan line Sn.

When the scan signal is supplied to the scan line Sn, the first transistor M1 included in each of the red pixel 140R, the green pixel 140G, and the blue pixel 140B is turned on. When the first transistor M1 is turned on, the data signal DS supplied to the data lines Dm-2, Dm-1, and Dm passes through the first transistor M1 to the gate of the second transistor M2. Supplied to the electrode.

In this case, a voltage corresponding to the data signal DS is charged in the first capacitor C1 included in each of the red pixel 140R, the green pixel 140G, and the blue pixel 140B. The voltage of the second electrode of the second transistor M2 is set to the first power source ELVDD during the period in which the scan signal is supplied to the scan line Sn.

In other words, since the second transistor M2 is turned on by the data signal DS, the voltage of the second electrode of the second transistor M2 is set to the first power source ELVDD. Here, since the third transistor M3 is set to the turn-off state, unnecessary current is not supplied to the organic light emitting diodes OLED (R), OLED (G), and OLED (B).

Thereafter, the supply of the scan signal to the scan line Sn is stopped, and the supply of the emission control signal to the emission control line En is stopped. When the supply of the scan signal to the scan line Sn is stopped, the first transistor M1 is turned off. When supply of the emission control signal to the emission control line En is stopped, the third transistor M3 is turned on.

When the third transistor M3 is turned on, the second electrode of the second transistor M2 included in each of the red pixel 140R, the green pixel 140G, and the blue pixel 140B is connected to the first power source ELVDD. The voltage is lowered to a predetermined voltage applied to the organic light emitting diodes OLED (R), OLED (G), and OLED (B). When the second electrode voltage of the second transistor M2 drops, the voltage of the gate electrode of the second transistor M2 also decreases by the second capacitor C2. Thereafter, the second transistor M2 supplies light corresponding to a voltage applied to its gate electrode to the organic light emitting diodes OLED (R), OLED (G), and OLED (B) to generate light having a predetermined brightness. do.

On the other hand, the organic light emitting diodes OLED (R), OLED (G), and OLED (B) deteriorate with time. When the organic light emitting diodes OLED (R), OLED (G), and OLED (B) deteriorate, voltage values applied to the organic light emitting diodes OLED (R), OLED (G), and OLED (B) increase. The brightness is lowered. In other words, as the organic light emitting diodes OLED (R), OLED (G), and OLED (B) deteriorate, the organic light emitting diodes OLED (R), OLED (G), and OLED (B) correspond to the same current. (In fact, as the organic light emitting diode deteriorates, the threshold voltage of the organic light emitting diode increases.)

The luminance deterioration phenomenon corresponding to the deterioration of the organic light emitting diode OLED is the largest in the blue pixel 140B and the lowest in the green pixel 140G, as shown in Equation 1 below.

In order to overcome this problem, in the present invention, the capacity of the second capacitor (C2) is set as shown in Equation (2). When the capacitance of the second capacitor C2 included in each of the red pixel 140R, the green pixel 140G, and the blue pixel 140B is set as shown in Equation 2, the organic light emitting diode OLED (R) and OLED (G) In response to deterioration of the OLED (B), the luminance of the red pixel 140R, the green pixel 140G, and the blue pixel 140B can be uniformly changed to some degree.

In other words, when the capacitance of the second capacitor C2 included in the blue pixel 140B having a short lifetime is set small, the degree of deterioration of the blue organic light emitting diode OLED (B) is increased by the gate electrode of the second transistor M2. When the capacitance of the second capacitor C2 included in the green pixel 140G, which is less reflected and has a long lifetime, is set to be large, the degree of deterioration of the green organic light emitting diode OLED (G) is increased by the gate of the second transistor M2. It is greatly reflected by the electrode.

That is, when the capacitance of the second capacitor C2 is set as shown in Equation 2, the pixels 140R, 140G, and 140B correspond to deterioration of the organic light emitting diodes OLED (R), OLED (G), and OLED (B). ), The amount of change in the gate electrode voltage of the second transistor M2 included in each change similarly to some extent, thereby displaying a uniform image. That is, in the present invention, the red pixel 140R, the green pixel 140G, and the blue pixel 140B can display a uniform image to some extent regardless of time.

On the other hand, the structure of the pixel in the present invention is not limited to the structure shown in Figure 3 can be formed in various ways.

5 illustrates a structure of a pixel according to another exemplary embodiment of the present invention. Here, since the structures of the red pixel, the green pixel, and the blue pixel are the same, the pixel will be described in FIG. 5 without distinguishing the red pixel, the green pixel, and the blue pixel.

Referring to FIG. 5, a pixel 140 according to another exemplary embodiment of the present invention is connected to an organic light emitting diode OLED, a data line Dm, a scan line Sn-1, Sn, and a light emission control line En. And a pixel circuit 142 for controlling the amount of current supplied to the organic light emitting diode OLED.

The anode electrode of the organic light emitting diode OLED is connected to the pixel circuit 142, and the cathode electrode is connected to the second power source ELVSS. Here, the voltage value of the second power source ELVSS is set lower than the voltage value of the first power source ELVDD. As described above, the organic light emitting diode OLED generates light having a predetermined luminance corresponding to the amount of current supplied from the pixel circuit 142.

The pixel circuit 142 controls the amount of current supplied to the organic light emitting diode OLED corresponding to the data signal supplied to the data line Dm when the scan signal is supplied to the scan line Sn. To this end, the pixel circuit 142 includes first to sixth transistors M1 to M6, a first capacitor C1, and a second capacitor C2.

The first electrode of the first transistor M1 is connected to the data line Dm, and the second electrode is connected to the first node N1. The gate electrode of the first transistor M1 is connected to the nth scan line Sn. The first transistor M1 is turned on when the scan signal is supplied to the nth scan line Sn and supplies the data signal supplied to the data line Dm to the first node N1.

The first electrode of the second transistor M2 is connected to the first node N1, and the second electrode is connected to the first electrode of the sixth transistor M6. The gate electrode of the second transistor M2 is connected to the second node N2. The second transistor M2 supplies a predetermined current to the organic light emitting diode OLED corresponding to the voltage applied to the second node N2.

The first electrode of the third transistor M3 is connected to the second electrode of the second transistor M2, and the second electrode is connected to the second node N2. The gate electrode of the third transistor M3 is connected to the nth scan line Sn. The third transistor M3 is turned on when a scan signal is supplied to the nth scan line Sn to connect the second transistor M2 in the form of a diode.

The gate electrode of the fourth transistor M4 is connected to the n-th scan line Sn-1, and the first electrode is connected to the second node N2. The second electrode of the fourth transistor M4 is connected to the initialization power supply Vint. The fourth transistor M4 is turned on when the scan signal is supplied to the n-th scan line Sn- 1 to change the voltage of the second node N2 to the voltage of the initialization power supply Vint.

The first electrode of the fifth transistor M5 is connected to the first power source ELVDD, and the second electrode is connected to the first node N1. The gate electrode of the fifth transistor M5 is connected to the emission control line En. The fifth transistor M5 is turned on when the emission control signal is not supplied from the emission control line En to electrically connect the first power source ELVDD and the first node N1.

The first electrode of the sixth transistor M6 is connected to the second electrode of the second transistor M2, and the second electrode is connected to the anode electrode of the organic light emitting diode OLED. The gate electrode of the sixth transistor M6 is connected to the emission control line En. The sixth transistor M6 is turned on when the emission control signal is not supplied to supply the current supplied from the second transistor M2 to the organic light emitting diode OLED.

The first capacitor C1 is connected between the second node N2 and the first power source ELVDD. The first capacitor C1 charges a voltage corresponding to the data signal supplied to the second node N2.

The second capacitor C2 is connected between the second node N2 and the second electrode of the second transistor M2. The second capacitor C2 transfers the amount of change in the second electrode voltage of the second transistor M2 to the second node N2.

An operation process of such a pixel will be described in detail with reference to the waveform diagram of FIG. 6. First, the emission control signal is supplied to the emission control line En so that the fifth transistor M5 and the sixth transistor M6 are turned off. The scan signal is supplied to the n-1 th scan line Sn-1 to turn on the fourth transistor M4. When the fourth transistor M4 is turned on, the voltage of the initialization power supply Vint is supplied to the second node N2. In other words, when the fourth transistor M4 is turned on, the second node N2 is initialized to the voltage of the initialization power supply Vint. Here, the voltage value of the initialization power supply Vint is set to a voltage value lower than that of the data signal.

Thereafter, the scan signal is supplied to the nth scan line Sn. When the scan signal is supplied to the nth scan line Sn, the first transistor M1 and the third transistor M3 are turned on. When the third transistor M3 is turned on, the second transistor M2 is connected in the form of a diode. When the first transistor M1 is turned on, the data signal supplied to the data line Dm is supplied to the first node N1 via the first transistor M1. At this time, since the voltage of the second node N2 is set to the voltage of the initialization power supply Vint (that is, lower than the voltage of the data signal supplied to the first node N1), the second transistor M2 Is turned on.

When the second transistor M2 is turned on, the data signal applied to the first node N1 is supplied to the second node N2. Here, since the data signal is supplied to the second node N2 via the second transistor M2 connected in the form of a diode, the first capacitor C1 corresponds to the data signal and the threshold voltage of the second transistor M2. The voltage is charged.

Meanwhile, the second electrode of the second transistor M2 is set to the voltage of the data signal while the voltage corresponding to the data signal is charged in the first capacitor C1.

After the first capacitor C1 is charged with a voltage corresponding to the data signal and the threshold voltage of the second transistor M2, the supply of the emission control signal is stopped, so that the fifth transistor M5 and the sixth transistor M6 are turned on. -On. When the sixth transistor M6 is turned on, the voltage of the second electrode of the second transistor M2 is reduced to the voltage applied to the organic light emitting diode OLED. When the second electrode voltage of the second transistor M2 drops, the voltage of the second node N2 also decreases by the second capacitor C2. Thereafter, the second transistor M2 supplies light corresponding to a voltage applied to its gate electrode to the organic light emitting diode OLED to generate light having a predetermined luminance.

Meanwhile, in FIG. 5, the capacitance of the second capacitor C2 is set differently in the red pixel, the green pixel, and the blue pixel as shown in Equation 2. In FIG. As shown in Equation 2, when the capacitances of the second capacitor C2 included in each of the red pixel, the green pixel, and the blue pixel are set, the luminance of the red pixel, the green pixel, and the blue pixel is adjusted in response to the deterioration of the OLED. It can be changed uniformly.

In other words, in the present invention, the second capacitor C2 is formed between the gate electrode and the second electrode of the second transistor M2, and the capacitances of the second capacitor C2 are respectively red, green, and blue pixels. By setting differently at, the lifetime characteristics of the organic light emitting diode may be compensated.

The above detailed description and drawings are merely exemplary of the present invention, but 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 meaning or 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 organic light emitting display device according to the embodiment of the present invention sets the capacitance of the second capacitor in response to the life characteristics of the red organic light emitting diode, the green organic light emitting diode, and the blue organic light emitting diode. It is possible to display an image which is somewhat uniform regardless of the life characteristics of the diodes.

Claims (8)

A data driver for supplying a data signal to the data lines; A scan driver for sequentially supplying low-level scan signals to the scan lines and sequentially supplying high-level emission control signals to the emission control lines; Red pixels, green pixels, and blue pixels positioned to be connected to the scanning lines and the data lines; Each of the red, green, and blue pixels An organic light emitting diode; A second transistor for supplying a current from a first power supply to a second power supply via the organic light emitting diode; A first capacitor connected between the gate electrode of the second transistor and the first power source; A second capacitor connected between the gate electrode and the second electrode of the second transistor; The capacitance of the second capacitor is set differently in the red pixel, the green pixel and the blue pixel, the organic light emitting display device. The method of claim 1, And the second capacitor is set to have a higher capacitance as the lifespan of the organic light emitting diode included in each of the red pixel, the green pixel, and the blue pixel is longer. The method of claim 2, The capacitance of the second capacitor included in the green pixel is set to the highest, the capacitance of the second capacitor included in the blue pixel is set to the lowest. The method of claim 1, A first transistor connected between the data line and the gate electrode of the second transistor and controlled by the scan signal; And a third transistor connected between the second transistor and the organic light emitting diode and controlled by the emission control signal. The method of claim 4, wherein and a light emission control signal supplied to an i (i is a natural number) light emission control line and overlapped with a scan signal supplied to an i th scan line. The method of claim 1, A first transistor connected between the data line and the first electrode of the second transistor and controlled by a scan signal supplied to an i (i is a natural number) scan line; A third transistor connected between the second electrode and the gate electrode of the second transistor and controlled by a scan signal supplied to the i-th scan line; A fourth transistor connected between an initialization power supply and a gate electrode of the second transistor and controlled by a scan signal supplied to an i-1 &lt; th &gt; scan line; A sixth transistor connected between the second transistor and the organic light emitting diode and controlled by an emission control signal supplied to an i-th emission control line; And a fifth transistor connected between the first electrode of the second transistor and the first power source, the fifth transistor being controlled by an emission control signal supplied to the i-th emission control line. . The method of claim 6, The voltage value of the initialization power supply is set to a voltage value lower than the voltage value of the data signal. The method of claim 6, And a light emission control signal supplied to the i th light emission control line and overlapped with a scan signal supplied to the i th scan line and an i-1 th scan line.

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