KR100683701B1 - Oled - Google Patents

Abstract

The present invention discloses an organic light emitting display device capable of dividing a cathode electrode to improve luminance unevenness due to a voltage drop of a cathode voltage.

An organic light emitting display device according to the present invention comprises: a plurality of pixels arranged in an image display portion of a substrate and driven according to a scan signal and a data signal; A gate driver and a data driver arranged at an outer portion of the image display unit to provide a scan signal and a data signal to the plurality of pixels; A power supply line arranged at an outer portion of the image display unit to provide a predetermined first voltage to the plurality of pixels; An electrode arranged on the substrate corresponding to the image display part to provide a predetermined second voltage to the plurality of pixels; An electrode line arranged on at least one side of the image display unit to provide the second voltage supplied from the outside to the electrode, wherein the electrode is divided into two or more electrode patterns, and the electrode line is two or more line patterns And the line patterns of the electrode lines are electrically contacted with the electrode patterns of the electrodes through contact holes, respectively, to correspond to the plurality of pixels arranged in the image display unit. The second voltage is provided to the pixels, respectively.

Description

Organic light emitting display device {OLED}

1 is a plan view of a conventional organic light emitting display device;

2 is an equivalent circuit diagram of a conventional organic light emitting display device;

3 is a view illustrating a voltage distribution of a cathode of a conventional organic light emitting display device;

4 is a plan view of an organic light emitting display device according to an embodiment of the present invention;

5 is an equivalent circuit diagram of an organic light emitting display device according to an embodiment of the present invention;

6 is a diagram illustrating a voltage distribution of a cathode of an organic light emitting display device according to an embodiment of the present invention;

7 is a cross-sectional structural view of an organic light emitting display device according to an embodiment of the present invention;

8 is a schematic plan view of an organic light emitting display device according to another embodiment of the present invention;

9 is a schematic plan view of an organic light emitting display device according to another embodiment of the present invention;

Explanation of symbols on the main parts of the drawings

200, 300: substrate 210: image display unit

220: gate driver 230: data driver

240, 540, 640: cathode electrode 250: power supply line

260, 561, 562, 563, 564, 661, 662: cathode power lines

270 terminal

The present invention relates to a flat panel display, and more particularly, to an organic light emitting display device in which a cathode electrode is divided.

An organic light emitting display device is a self-luminous display device in which a plurality of pixels are arranged in a display area, each pixel including at least one switching thin film transistor, one driving thin film transistor, a capacitor, and an EL element. The EL element includes an organic film layer having an anode electrode, a cathode electrode, and a light emitting layer interposed between these electrodes.

Such an organic light emitting display device has a back light emitting structure and a top light emitting structure according to a direction in which light emitted from the light emitting layer of the EL element of each pixel arranged in the pixel region is emitted. A top emission type organic light emitting display device is a device in which light emitted from an organic light emitting layer of a pixel is emitted in a direction opposite to a TFT array substrate on which pixels are arranged, and a rear light emitting structure in which light is emitted toward a TFT array substrate on which pixels are arranged. It is advantageous in terms of opening ratio in comparison.

In an organic light emitting display device, a cathode electrode, which is an upper electrode, is formed as a front electrode to provide a cathode voltage in common to a plurality of pixels arranged in a pixel area. As described above, the cathode electrode formed in the form of the front electrode has a nonuniform cathode voltage applied to each pixel depending on the position of the pixel region due to the voltage drop caused by the resistive component.

To solve this problem, a technique for forming a cathode power line under the cathode electrode and connecting the cathode power line with the cathode electrode to compensate for the voltage drop of the cathode electrode has been proposed.

1 is a plan view of a conventional organic light emitting display device.

Referring to FIG. 1, a conventional organic light emitting display device includes a data driver 130 for providing a data signal to a pixel 10 arranged on an image display unit 110 of a substrate 100. It is arranged at the outer edge of the. In addition, a gate driver 120 for providing a scan signal to the pixels 10 arranged in the image display unit 110 is arranged at an outer portion of the image display unit 110.

On the upper portion of the image display unit 110, the cathode electrode 140 is arranged in the form of a front electrode, and the cathode power line 160 for providing a predetermined cathode voltage to the cathode electrode 140 through the terminal unit 170 is provided. Are arranged. The cathode power line 160 includes a contact hole 165 for connection with the cathode electrode 140 to be in electrical contact with the cathode electrode 140.

In addition, the conventional organic light emitting display device includes a power supply line 150 for providing a power supply voltage to the pixel of the image display unit 110. The power supply line 150 includes a plurality of wiring lines 151 arranged on the image display unit 110.

2 is a circuit diagram illustrating a conventional organic light emitting display device.

Referring to FIG. 2, in the conventional organic light emitting display device, a plurality of pixels 10 are arranged in a matrix form of columns and rows in the image display unit 110. Each pixel 10 includes one corresponding gate line among the plurality of gate lines G1 -Gm, one corresponding data line among the plurality of data lines D1 -Dn, and one of the plurality of power lines V1 -Vn. Each is connected to one corresponding power line.

The pixel 10 includes a switching thin film transistor 11, a capacitor 12, a driving thin film transistor 13, and an organic light emitting diode 14. In the related art organic light emitting diode display, each pixel 10 connected to each gate line, data line, and power line is arranged in the same manner, and the same cathode voltage Vss is applied from the cathode electrode 140 to each pixel 10. Is provided.

FIG. 3 illustrates the voltage distribution of the cathode electrode 140 in the image display unit 110 in the conventional organic light emitting display device shown in FIG. 1. In FIG. 3, V11 to V17 indicate cathode voltages provided from the terminal unit 170 to the cathode electrode 140 when the cathode power line 160 is arranged at the left outer portion of the image display unit 110. As the voltage drops to, the voltage value of the cathode voltage decreases due to the voltage drop.

Referring to FIG. 3, the conventional organic light emitting display device is applied to a pixel arranged at a portion farther from the terminal portion 170 than a pixel arranged at a portion adjacent to the terminal portion 170 due to the voltage drop of the cathode voltage. The cathode voltage is lowered. As described above, the cathode voltage is lowered toward the upper side and to the left side of the image display unit 110 so that the cathode voltage applied to the plurality of pixels arranged in the image display unit 110 is arranged in the pixel in the image display unit 110. There was a problem that the non-uniformity caused by the position causes a non-uniform brightness.

In addition, in the conventional organic light emitting display device, the resistance voltage of the cathode power line increases as the cathode voltage of the cathode power line 160 is farther from the terminal unit 170 provided with the cathode voltage from the outside. Therefore, a portion of the cathode power line 160 far away from the terminal portion 170 may have a lower cathode voltage than a portion adjacent to the terminal portion 170 due to the resistance component of the cathode power line 160.

Therefore, as shown in FIG. 3, due to the voltage drop in the cathode power supply line 160, the voltages provided to the pixels arranged in the image display unit 110 are different and are far from the portion adjacent to the terminal unit 170. There is a problem that the cathode voltage applied to the pixels arranged in the portion becomes nonuniform, resulting in uneven luminance.

In addition, the larger the area of the organic light emitting display device, the more uneven the cathode voltage according to the arrangement position of the pixels due to the voltage drop of the cathode voltage, and thus the problem of the luminance unevenness becomes more serious.

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic light emitting display device capable of improving luminance unevenness by dividing a cathode electrode to prevent a cathode voltage drop.

In order to achieve the above object, a substrate having an image display unit; A plurality of pixels arranged in an image display portion of the substrate and driven according to a scan signal and a data signal; A gate driver arranged at an outer portion of the image display unit to provide a scan signal to the plurality of pixels; A data driver arranged at an outer periphery of said image display section for providing a data signal to a plurality of pixels arranged in said image display section; A power supply line arranged on an outer portion of the image display unit to provide a first voltage to the plurality of pixels; An electrode arranged on the image display part of the substrate to provide a second voltage to a plurality of pixels arranged in the image display part, wherein the electrode is divided into two or more electrode patterns, and the electrode pattern is arranged in the image display part An organic light emitting display device is configured to provide the second voltage to a corresponding pixel among a plurality of pixels arranged in the plurality of pixels.

Second voltages having the same level are applied to the divided electrode patterns of the electrodes from the outside. Pixels corresponding to the first electrode pattern of the cathode and pixels corresponding to the second electrode pattern of the plurality of pixels have the same structure. The electrode is divided along a direction in which a second voltage crosses the direction in which the electrode is applied.

In addition, the present invention is a substrate having an image display; A plurality of pixels arranged in an image display portion of the substrate and driven according to a scan signal and a data signal; A gate driver arranged at an outer portion of the image display unit to provide a scan signal to the plurality of pixels; A data driver arranged at an outer portion of the image display unit to provide a data signal to the plurality of pixels; A power supply line arranged at an outer portion of the image display part to provide a predetermined first voltage to the plurality of pixels; An electrode arranged on the substrate corresponding to the image display part to provide a predetermined second voltage to the plurality of pixels; An electrode line arranged on at least one side of the image display unit to provide the second voltage supplied from the outside to the electrode, wherein the electrode is divided into two or more electrode patterns, and the electrode line is two or more line patterns And are arranged to correspond to the electrode patterns of the electrodes, and the line patterns of the electrode lines are electrically contacted with the electrode patterns of the electrodes through contact holes, respectively, to correspond to the plurality of pixels arranged in the image display unit. An organic light emitting display device for providing the second voltage to each pixel may be provided.

The electrode is divided in the longitudinal direction of the electrode line. Pixels corresponding to the first electrode pattern of the cathode and pixels corresponding to the second electrode pattern of the plurality of pixels have the same structure.

The line patterns of the electrode lines are all arranged on one side of the image display unit or are arranged on both sides of the image display unit to be in electrical contact with one side of the electrode pattern through the contact hole.

The second voltage of the same level is applied to the electrode pattern of the electrode from the outside through the line pattern of each electrode line.

Line patterns of the electrode lines are respectively arranged on both sides of the image display unit, and are electrically contacted with both sides of the electrode pattern through respective contact holes, respectively, from the outside through the line patterns of the respective electrode lines on the electrode patterns of the electrodes. Second voltages of the same level are simultaneously applied from both sides of each electrode pattern.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

4 illustrates a planar structure of an organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 4, an organic light emitting display device according to an exemplary embodiment includes a substrate 200, a data driver 230, and a gate driver including an image display unit 210 on which a plurality of pixels 20 are arranged. 220. Although only one pixel is illustrated in the image display unit 210, as illustrated in FIG. 5, the plurality of pixels 20 are arranged in the image display unit 210 in a matrix form of columns and rows. The data driver 230 is used to provide a data signal to the pixels 20 arranged in the image display unit 210. The data driver 230 is arranged in the lower outer portion of the image display unit 210. The gate driver 220 is used to provide a scan signal to the pixel 20 arranged in the image display unit 210, and is arranged at one side of an outer portion of the image display unit 210.

The organic light emitting display device of the present invention further includes a power supply line 250, a cathode electrode 240, and a cathode power line 260. The power supply line 250 is to provide a power voltage to the pixel 20 and is arranged at an outer portion of the image display unit 210. The power supply line 250 includes a plurality of wiring lines 251 arranged on the image display unit 210. The wiring line 251 corresponds to V1-Vn of FIG. 5.

The cathode electrode 240 is arranged on the image display unit 210 and is divided into at least two electrode patterns 241 and 242. The cathode power line 260 is divided into two line patterns 261 and 262 corresponding to the divided electrode patterns 241 and 242 of the cathode electrode 240 to form an electrode pattern 241, Corresponding to 242. The cathode power line 260 includes a first line pattern 261 and the second electrode arranged to correspond to the first electrode pattern 241 of the electrode patterns 241 and 242 of the cathode electrode 240. The second line pattern 262 is arranged to correspond to the pattern 242.

The first line pattern 261 of the cathode power line 260 includes a contact hole 265 for connection with the first electrode pattern 241 of the cathode electrode 240. The first line pattern 261 of the cathode power line 260 is electrically contacted with the first electrode pattern 241 of the cathode electrode 240 through the contact hole 265 to contact the terminal portion 270 from the outside. A predetermined cathode voltage (Vss1 of FIG. 5) provided through the same is provided to the first electrode pattern 241 of the cathode electrode 240.

The second line pattern 262 of the cathode power line 260 includes a contact hole 266 for connection with the second electrode pattern 242 of the cathode electrode 240. The second line pattern 262 of the cathode power line 260 is electrically contacted with the second electrode pattern 242 of the cathode electrode 240 through the contact hole 266 to contact the terminal portion 270 from the outside. A predetermined cathode voltage (Vss2 of FIG. 5) provided through the same is provided to the second electrode pattern 242 of the cathode electrode 240.

In this case, the cathode electrode 240 is divided into two along the longitudinal direction of the cathode power line 260. That is, the cathode voltage is divided in two along the direction crossing the direction in which the cathode voltage is applied to the cathode electrode. The first electrode pattern 241 of the cathode electrode 240 is arranged to correspond to the upper portion of the image display portion 210, and the second electrode pattern 242 corresponds to the lower portion of the image display portion 210. Are arranged.

Accordingly, the pixels arranged on the upper side of the plurality of pixels 20 arranged on the image display unit 210 may be provided to the first line pattern 261 of the cathode power line 260 through the terminal unit 270 from the outside. The first cathode voltage Vss1 is provided through the first electrode pattern 241 of the cathode electrode 240. In addition, the pixel 20 arranged on the lower side of the plurality of pixels 20 arranged on the image display unit 210 is connected to the second line pattern 262 of the cathode power line 260 through the terminal unit 270 from the outside. The provided second cathode voltage Vss2 is provided through the second electrode pattern 242 of the cathode electrode 240.

As shown in FIG. 4, the first cathode voltage Vss1 from the terminal portion 270 is passed through the first line pattern 261 of the cathode power line 260 to form the first electrode pattern 241 of the cathode electrode 240. The second source voltage of the cathode power line 260 is equal to the distance applied to the second electrode pattern 242 through the second line pattern 262 from the terminal portion 270. It is preferable that the first line pattern 261 and the second line pattern 262 are arranged.

In addition, the first cathode voltage Vss1 applied from the terminal portion 270 to the first electrode pattern 241 of the cathode electrode 240 through the first line pattern 261 and the second line pattern (from the terminal portion 270). The voltage drop of the first line pattern 261 and the second line pattern 262 of the cathode power line 260 is made to be equal to the second cathode voltage Vss2 applied to the second electrode pattern 242 through 262. Is preferably the same.

In this case, the cathode voltage Vss1 applied from the terminal portion 270 to the first line pattern 261 and the cathode voltage Vss2 applied from the terminal portion 270 to the second line pattern 262 apply the same cathode voltage. It is desirable to. Therefore, as shown in FIG. 6, it is preferable to arrange the cathode voltage distributions of the first electrode pattern 241 and the second electrode pattern 242 of the cathode electrode 240 to be the same.

On the other hand, the distance between the terminal portion 270 and the first cathode voltage Vss1 applied to the first electrode pattern 241 of the cathode electrode 240 through the first line pattern 261 of the cathode power line 260. The first line pattern 261 and the first line pattern 261 of the cathode power line 260 are different from the distance that the second cathode voltage Vss2 is applied to the second electrode pattern 242 through the second line pattern 262 from 270. When the two line patterns 262 are arranged, the first cathode voltage Vss1 and the terminal portion applied from the terminal portion 270 to the first electrode pattern 241 of the cathode electrode 240 through the first line pattern 261. The second cathode voltage Vss2 applied to the second electrode pattern 242 through the second line pattern 262 from 270 is different from each other.

In this case, in consideration of the voltage drop generated through the first line pattern 261 and the voltage drop generated through the second line pattern 262, the first line provided from the terminal part 270 to the first line pattern 261. It is preferable to set the cathode voltage Vss1 and the second cathode voltage Vss2 provided from the terminal portion 270 to the second line pattern 262. As a result, the first cathode voltage Vss1 and the second line pattern 262 are finally applied to the first electrode pattern 241 of the cathode electrode 240 through the first line pattern 261. By making the second cathode voltage Vss2 finally applied to the electrode pattern 242 the same, the first electrode pattern 241 and the second electrode pattern 242 of the cathode electrode 240 as shown in FIG. It is desirable to make the voltage distribution the same.

6 illustrates the voltage distribution of the cathode electrode 240 in the image display unit 210 in the organic light emitting display device of the present invention shown in FIG. In FIG. 6, V21 to V24 represent cathode voltages provided from the terminal unit 270 to the cathode electrode 240 when the cathode power line 260 is arranged at the left outer portion of the image display unit 210. The voltage value of the cathode voltage decreases toward V24.

In the organic light emitting display device of the present invention, the first electrode pattern of the cathode electrode 240 is formed from the terminal portion 270 through the first line pattern 261 and the second line pattern 262 of the cathode power line 260. Since the first cathode voltage Vss1 and the second cathode voltage Vss2 provided to the 241 and the second electrode pattern 242 are equally applied, the pixels and the lower portion arranged in the upper portion of the image display unit 210 are applied. The cathode voltage applied to the arranged pixels is distributed as shown in FIG.

Accordingly, the cathode voltage applied to the cathode of the conventional front electrode type has a voltage deviation of V11 to V17, whereas the cathode voltage of the divided cathode electrode of the present invention has a voltage deviation of V21 to V24. . Therefore, the voltage uniformity is improved by dividing the cathode electrode, thereby solving the luminance non-uniformity problem.

In addition, in the organic light emitting display device of the present invention, since the cathode electrode is divided into two along the cathode power line, the length of the first line pattern 261 and the second line pattern 262 of the cathode power line is changed to the conventional cathode power line. It is possible to arrange shorter than the length of 160. Therefore, it is possible to reduce the voltage drop through the cathode power supply line as compared with the prior art, thereby improving the uniformity of the cathode voltage according to the position of the pixel arranged in the image display unit 210.

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

Referring to FIG. 5, an organic light emitting display device according to an exemplary embodiment of the present invention includes a plurality of pixels 20 arranged in a matrix form of columns and rows in the image display unit 210, and also includes a gate driver 220. A plurality of gate lines G1-Gm for providing a scanning signal to the pixel 20, and a plurality of data lines D1-Dn for providing a data signal from the data driver 230 to the pixel 20. And a power supply line V1 -Vn for supplying a power supply voltage to the pixel 20 from the power supply line 250.

Each pixel 20 includes one gate line among the plurality of gate lines G1 -Gm, one data line among the plurality of data lines D1 -Dn, and one of the plurality of power lines V1 -Vn. Each is connected to one corresponding power line. For example, the pixel 20k arranged in the 20th column and the first row corresponds to one of the gate lines Gk and a plurality of data lines D1 -Dn of the gate lines G1 -Gm. A data line D1 and a plurality of power lines V1 -Vn are respectively connected to a corresponding power line V1. In addition, the pixel 20k + 1 arranged in the 20k + 1th column and the first row includes one gate line Gk + 1 and a plurality of data lines D1- corresponding to one of the plurality of gate lines G1 -Gm. One data line D1 of Dn and one power line V1 of a plurality of power lines V1 -Vn are respectively connected.

Among the plurality of pixels 20 arranged in the image display unit 210, a plurality of pixels arranged above the image display unit 210, that is, a plurality of pixels connected to the first gate line G1 to the k-th gate line Gk. The pixel of is connected to the first electrode pattern 241 of the first electrode pattern 241 and the second electrode pattern 242 of the cathode electrode 240 is provided with a first cathode voltage (Vss1), the image display unit ( A plurality of pixels arranged under the 210, that is, a plurality of pixels connected to the k + 1th gate line Gk + 1 to the mth gate line Gm, is connected to the second electrode pattern 242 to form a second pixel. The cathode voltage Vss2 is provided.

For example, the pixel 20k arranged in the 20th column and the first column includes two thin film transistors 21k and 23k, one capacitor 22k, and an organic light emitting element (EL element) 24k. . The thin film transistor is configured to correspond to a switching thin film transistor 21k and a data signal provided through the switching thin film transistor 21k to transfer a data signal provided from the data line according to a scan signal provided from a gate line. A driving thin film transistor 23k for driving the EL element 24k is provided.

The switching thin film transistor 21k has a gate connected to one gate line Gk of the plurality of gate lines G1-Gm, and one data of the plurality of data lines D1-Dn. A source is connected to the line D1, and a drain is connected to one electrode of the capacitor 22k.

The driving thin film transistor 23k has a gate connected to one electrode of the capacitor 22k and a corresponding one of the plurality of power lines V1 -Vn and the other of the capacitor 22k. The source is connected to the electrode.

In the EL element 24k, one electrode, for example, an anode electrode is connected to the drain electrode of the driving thin film transistor 23k, and the other electrode, for example, a cathode electrode, is connected to the first cathode voltage Vss1. . That is, the first ground voltage Vss1, which is the first cathode voltage, is provided from the first electrode pattern 241 of the cathode electrode 240 to the cathode of the EL element 24k.

On the other hand, the pixel 20k + 1 arranged in the 20k + 1th column and the first row has two thin film transistors 21k + 1, 23k + 1, one capacitor 22k + 1, and an EL element 24k +. 1) is provided. The thin film transistor includes a switching thin film transistor 21k + 1 and a data signal provided through the switching thin film transistor 21k + 1 to transfer a data signal provided from a data line according to a scan signal provided from a gate line. Correspondingly, a driving thin film transistor 23k + 1 for driving the EL element 24k + 1 is provided.

The switching thin film transistor 21k + 1 has a gate connected to a corresponding gate line Gk + 1 of the plurality of gate lines G1-Gm, and a corresponding one of the plurality of data lines D1-Dn. A source is connected to one data line D1 and a drain is connected to one electrode of the capacitor 22k + 1.

The driving thin film transistor 23k + 1 has a gate connected to one electrode of the capacitor 22k + 1, and one power line V1 and a capacitor of the plurality of power lines V1-Vn. The source is connected to the other electrode of 22k + 1).

In the EL element 24k + 1, one electrode, for example, an anode electrode is connected to the drain electrode of the driving thin film transistor 23k + 1, and the other electrode, for example, the cathode electrode, has a second ground voltage Vss2. ) That is, the second ground voltage Vss2 which is the second cathode voltage is provided from the second electrode pattern 242 of the cathode electrode 240 to the cathode electrode of the EL element 24k + 1.

Referring to FIG. 5, pixels arranged to correspond to the first electrode pattern 241 of the cathode electrode 240 and pixels arranged to correspond to the second electrode pattern 242 are arranged in the same structure. The pixel structure of the cathode electrode 240 arranged on the first electrode pattern 241, that is, the pixel structure connected to the first gate line G1 to the k-th gate line Gk and the second electrode pattern 242. The pixels arranged, that is, the pixels arranged in the k + 1th gate lines Gk + 1 to m-th gate line Gm, are arranged in the same manner.

For example, elements 21k-24k constituting the pixel 20k arranged in the kth gate line Gk and pixels 20k + 1 arranged in the k + 1th gate line Gk + 1 are configured. The elements 21k + 1-24k + 1 are arranged in the same structure. That is, each pixel is arranged between adjacent gate lines, and EL elements of each pixel connected to the current gate line, for example, Gk, are arranged adjacent to the next gate line, for example, Gk + 1.

7 illustrates a cross-sectional structure of an organic light emitting display device according to an embodiment of the present invention. In FIG. 7, four pixels 20k-1 are arranged adjacent to the first electrode pattern 241 and the second electrode pattern 242 of the cathode electrode 240 among the plurality of pixels arranged in the image display unit 210. , (20k), (20k + 1), (20k + 2), that is, the pixel 20k-1 connected to the k-th gate line Gk-1 and the pixel 20k connected to the k-th gate line Gk And the pixel 20k + 1 connected to the k + 1th gate line Gk + 1 and the pixel 20k + 2 connected to the k + 2th gate Gk + 2. FIG. 7 shows an organic electroluminescent element (EL element) among each pixel and a driving thin film transistor for driving the EL element. At this time, the remaining pixels arranged in the image display unit 210 also have a cross-sectional structure as shown in FIG. 7.

Referring to FIG. 7, in the organic light emitting display device according to the embodiment of the present invention, four pixels 20k-1, 20k, 20k + 1, and 20k + 2 are formed on the substrate 300. Are arranged. That is, the first to fourth semiconductor layers 310, 320, and 330 of the pixels 20k-1, 20k, 20k + 1, and 20k + 2 are disposed on the buffer layer 305 of the substrate 300. , 340 is formed.

The first semiconductor layer 310 for the first pixel 20k includes first source / drain regions 311 and 315 doped with a predetermined conductivity type, for example, p-type impurities. The second semiconductor layer 320 for the second pixel 20k includes second source / drain regions 321 and 325 doped with p-type impurities. The third semiconductor layer 330 for the third pixel 20k + 1 includes third source / drain regions 331 and 335 doped with p-type impurities. The fourth semiconductor layer 340 for the fourth pixel 20k + 2 includes fourth source / drain regions 341 and 345 doped with p-type impurities.

A gate insulating film 350 is formed on the substrate, and gate electrodes for the first to fourth pixels 20k-1, 20k, 20k + 1, and 20k + 2 are formed on the gate insulating film 350. 361, 363, 365, and 367 are formed to correspond to the first to fourth semiconductor layers 310, 320, 330, and 340. In this case, gate lines 362, 364, 366, and 368 are formed at one side of the gate electrodes 361, 363, 365, and 367 to which the gate electrodes 361, 363, 365, and 367 are connected. In FIG. 5, the gate line 362 is the k-th gate line, the gate line 364 is the k-th gate line, the gate line 366 is the k + 1 gate line, and the gate line 368 is k ++. Two gate lines are shown.

An interlayer insulating film 360 is formed on the substrate. Source / drain regions 311, 315, 321, 325, and 331, 335 of the first through fourth semiconductor layers 310, 320, 330, and 340 in the gate insulating film 350 and the interlayer insulating film 350. ) And (341, 345), contact holes 351, 352, (353, 354), (355, 356), (357, 358) are formed.

First through fourth semiconductor layers 310, 320, 330, through the contact holes 351, 352, 353, 354, 355, 356, and 357, 358 on the interlayer insulating layer 360, respectively. First to fourth pixels 20k-1 and 20k electrically contacting source / drain regions 311 and 315, 321 and 325, 331 and 335 and 341 and 345 of 340. Source / drain electrodes 371, 375, 381, 385, 391, 395, and 401,405 for (20k + 1), (20k + 2) are formed. At this time, although not shown in the drawing, a plurality of wiring lines 251 of a plurality of data lines and a power supply line 250 are formed.

A protective film 410 is formed on the substrate. The passivation layer 410 includes source / drain electrodes 371, 375, 381, 385, and 391 that correspond to each of the pixels 20k-1, 20k, 20k + 1, and 20k + 2. 395 and via holes 411, 413, 415, 417 exposing portions of the drain electrodes 375, 385, 395, 405.

Through the via holes 411, 413, 415, and 417 on the passivation layer 410, the first to fourth pixels 20k-1, 20k, 20k + 1, and 20k + 2, respectively. Pixel electrodes 421, 423, 425, and 427 of the first to fourth pixels 20k-1, 20k, 20k + 1, and 20k + 2 connected to the drain electrodes 375, 385, 395, and 405 of the thin film transistor. Is formed.

The pixel isolation layer 430 is formed on the substrate. The pixel isolation layer 430 exposes the openings 431 and 433 exposing the pixel electrodes 421, 423, 425, and 427 of the first to fourth pixels 20k-1, 20k, 20k + 1, and 20k + 2, respectively. , 435, 437.

Organic film layers 441, 443, 445, and 447 are formed on the pixel electrodes 421, 423, 425, and 427 in the openings 431, 433, 435, and 437, respectively. The organic layer 441, 443, 445, and 447 may include at least one organic layer selected from a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a hole suppression layer.

The cathode electrode 450 is formed on the substrate. The cathode electrode 450 is divided into two electrode patterns 451 and 452 so that the first and second pixels of the first to fourth pixels 20k-1, 20k, 20k + 1, and 20k + 2 are separated. The first electrode pattern 451 is formed at a portion corresponding to 20k-1 and 20k, and the second electrode pattern 452 is formed at a portion corresponding to the third and fourth pixels 20k + 1 and 20k + 2. Is formed. In this case, the cathode electrode 450 corresponds to the cathode electrode 240 of FIG. 5, and the first electrode pattern 451 and the second electrode pattern 452 respectively correspond to the first electrode pattern 241 of FIG. 5. It corresponds to the second electrode pattern 242.

Therefore, the EL element 24k-1 of the first pixel 20k-1 includes a cathode electrode composed of the anode electrode 421 and the first electrode pattern 451 and an organic film layer 441 interposed between the two electrodes. The EL element 24k of the second pixel 20k includes a cathode electrode composed of an anode electrode 423 and a first electrode pattern 451 and an organic film layer 443 interposed between the two electrodes.

On the other hand, the EL element 24k + 1 of the third pixel 20k + 1 has a cathode electrode composed of an anode electrode 425 and a second electrode pattern 452 and an organic film layer 445 interposed between the two electrodes. The EL element 24k + 2 of the fourth pixel 20k + 2 includes a cathode electrode composed of an anode electrode 427 and a second electrode pattern 452 and an organic layer 447 interposed between the two electrodes. It includes.

As shown in FIG. 5, the plurality of pixels 20 are regularly arranged in the image display unit 210, so that all the pixels are arranged in the same layout on the substrate. As described above, the pixels arranged in correspondence with the first electrode pattern 241 and the pixels arranged in correspondence with the second electrode pattern 242 of the cathode electrode 240 are arranged in the same structure. For example, an arrangement structure of pixels 20k arranged between adjacent gate lines 364 and 366 and pixels 20k + 1 arranged between adjacent gate lines 366 and 368 are the same, and each pixel is the same. Pixel electrodes 423 and 425 of (20k) and (20k + 1) are arranged adjacent to the next gate lines 366 and 368, respectively.

8 schematically illustrates a planar structure of an organic light emitting display device according to another embodiment of the present invention. The organic light emitting display device according to another embodiment of the present invention is almost similar in structure to the organic light emitting display device shown in the first embodiment. The only difference is that the cathode power line 560 is arranged on both sides of the image display unit 510.

Referring to FIG. 8, in the organic light emitting display device according to another exemplary embodiment, the cathode electrode 540 is divided into two electrode patterns 541 and 542, and two electrode patterns 541 and ( The first electrode pattern 541 is arranged corresponding to the upper side of the image display unit 510 in which a plurality of pixels are arranged, and the second electrode pattern 542 is arranged corresponding to the lower side of the image display unit 510. do.

Line patterns 561 and 563 of the cathode electrode line 560 are arranged on both sides of the image display unit 510, respectively, so that contact holes 565 are formed at both ends of the first electrode pattern 541 of the cathode electrode 540, respectively. 567). In addition, line patterns 562 and 564 of the cathode electrode line 560 are arranged at both sides of the lower portion of the image display unit 510, respectively, and contact holes may be formed at both ends of the second electrode pattern 542 of the cathode electrode 540. 566, 568).

In another embodiment of the present invention, the cathode voltage is supplied from both sides of the first electrode patterns 541 and 542 of the cathode electrode 540, thereby reducing luminance unevenness according to the unevenness of the cathode voltage caused by the voltage drop of the cathode electrode. It can be improved further.

FIG. 9 schematically illustrates a planar structure of an organic light emitting display device according to still another embodiment of the present invention. The organic light emitting display device according to another embodiment of the present invention is almost similar in structure to the organic light emitting display device shown in the first embodiment. The only difference is that the cathode power supply line 660 is arranged on both sides of the image display unit 610.

Referring to FIG. 9, in the organic light emitting display device according to another exemplary embodiment, the cathode electrode 640 is divided into two electrode patterns 641 and 642, and two electrode patterns 641, The first electrode pattern 641 is arranged corresponding to the upper side of the image display unit 610 in which a plurality of pixels are arranged, and the second electrode pattern 642 corresponds to the lower side of the image display unit 610. Are arranged.

Power patterns 661 and 662 of the cathode electrode line 660 are arranged at both sides of the image display unit 610, respectively. A line pattern 661 of the cathode electrode line 660 is arranged on one side of the image display unit 610 so that one end of the first electrode pattern 641 and the contact hole 665 of the cathode electrode 640 are arranged. Is electrically contacted through In addition, a second line pattern 662 is arranged on one side of the lower side of the image display unit 610 opposite to the first line pattern 661, so that the second electrode pattern 642 of the cathode electrode 640 is arranged. Is electrically contacted through the contact hole 666 at one end thereof.

In the exemplary embodiment of the present invention, an organic light emitting display device having a structure in which a cathode electrode is electrically contacted to a cathode power line through a contact hole has been described. However, when applied to an organic light emitting display device having no cathode power line. In addition, it is possible to improve the luminance non-uniformity problem caused by the voltage drop of the cathode voltage.

Further, in the embodiment of the present invention, the driving thin film transistor and the EL element constituting each pixel are illustrated as having a cross-sectional structure as shown in FIG. 6, but are not necessarily limited thereto, and may have various cross-sectional structures. In addition, although the back light emitting structure is illustrated in FIG. 6 with respect to the device, it is applicable to both devices having a front side and a double side light emitting structure.

In the exemplary embodiment of the present invention, each pixel is composed of two thin film transistors, one capacitor, and an EL element. However, the present invention is not limited thereto, and it is applicable to an organic light emitting display device having various pixel structures.

In the embodiment of the present invention, the cathode electrode is divided into two electrode patterns, but it is possible to divide the cathode electrode into a plurality of electrode patterns as necessary. In addition, in the embodiment of the present invention, the cathode electrode is divided into upper and lower parts. However, the cathode electrode may be divided into left and right sides according to the arrangement of components constituting the organic light emitting display device.

In addition, although the embodiment of the present invention exemplifies the cathode electrode in the organic light emitting display device, the present invention is not limited thereto, and the present invention can be applied to any display device having an electrode structure in the form of a front electrode.

According to the embodiment of the present invention as described above, by dividing the cathode electrode and applying the cathode voltage to each divided electrode pattern, the problem of luminance unevenness due to the voltage drop of the cathode voltage can be solved to improve the image quality. There is an advantage to that. An organic light emitting display device in which the cathode electrode of the present invention is divided into a plurality of electrode patterns to provide a cathode voltage to each of them is advantageous in a large area display device.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

Claims (11)

A substrate having an image display section; A plurality of pixels arranged in an image display portion of the substrate and driven according to a scan signal and a data signal; A gate driver arranged at an outer portion of the image display unit to provide a scan signal to the plurality of pixels; A data driver arranged at an outer periphery of said image display section for providing a data signal to a plurality of pixels arranged in said image display section; A power supply line arranged on an outer portion of the image display unit to provide a first voltage to the plurality of pixels; An electrode arranged above the image display part of the substrate and configured to provide a second voltage to a plurality of pixels arranged in the image display part; The electrode is divided into a plurality of electrode patterns, And the electrode pattern provides the second voltage to a corresponding pixel among a plurality of pixels arranged in the image display unit. The organic light emitting display device as claimed in claim 1, wherein a second voltage having the same level is applied to the divided electrode patterns of the electrodes from the outside. The organic light emitting display device of claim 1, wherein the pixel corresponding to the first electrode pattern of the cathode electrode and the pixel corresponding to the second electrode pattern have the same structure among the plurality of pixels. The organic light emitting display device of claim 1, wherein the electrode is divided in a direction crossing a direction in which a second voltage is applied to the electrode. A substrate having an image display section; A plurality of pixels arranged in an image display portion of the substrate and driven according to a scan signal and a data signal; A gate driver arranged at an outer portion of the image display unit to provide a scan signal to the plurality of pixels; A data driver arranged at an outer portion of the image display unit to provide a data signal to the plurality of pixels; A power supply line arranged at an outer portion of the image display unit to provide a predetermined first voltage to the plurality of pixels; An electrode arranged on the substrate corresponding to the image display part to provide a predetermined second voltage to the plurality of pixels; An electrode line arranged on at least one side of the image display unit to provide the second voltage supplied from the outside to the electrode, The electrode is divided into a plurality of electrode patterns, The electrode line is divided into a plurality of line patterns, respectively arranged to correspond to the electrode pattern of the electrode, The line patterns of the electrode lines are electrically contacted with the electrode patterns of the electrodes through contact holes, respectively, to provide the second voltages to corresponding pixels among the plurality of pixels arranged in the image display unit. Light emitting display device. The organic light emitting display device of claim 5, wherein the electrode is divided in a length direction of the electrode line. The organic light emitting diode display as claimed in claim 5, wherein the line patterns of the electrode lines are all arranged on one side of the image display unit or are arranged on both sides of the image display unit to be in electrical contact with one side of the electrode pattern through the contact hole. EL display device. The organic light emitting display device of claim 7, wherein a second voltage having the same level is applied to the electrode pattern of the electrode from the outside through a line pattern of each electrode line. The organic light emitting display device according to claim 5, wherein the line patterns of the electrode lines are arranged on both sides of the image display unit, and are electrically contacted with both sides of the electrode pattern through respective contact holes. The organic light emitting display device according to claim 9, wherein a second voltage having the same level is externally applied from both sides of the electrode pattern to the electrode pattern of the electrode through the line pattern of each electrode line. The organic light emitting display device of claim 5, wherein the pixel corresponding to the first electrode pattern of the cathode electrode and the pixel corresponding to the second electrode pattern of the plurality of pixels have the same structure.

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