KR100806815B1 - Driving device and driving method of organic light emitting device - Google Patents

Abstract

According to an embodiment of the present invention, the uniformity of the display screen may be improved by predicting the potential difference generated on the scan electrode line in advance and precharging the expected potential difference to the data electrode line. The driving apparatus generates a scan electrode line driver sequentially applying negative scan pulses to a plurality of scan electrode lines, and a potential difference corresponding to a potential difference generated on any one of the plurality of scan electrode lines. Applying a predetermined current to the potential difference generator and the potential difference generator to cause the potential difference generator to generate a potential difference, and precharging the data electrode line by applying the generated potential difference to the data electrode line to emit EL cells. Data transfer to supply a predetermined current to the plurality of data electrode lines for It characterized in that it comprises a line driver.

Organic EL, comb, luminance, potential difference, precharging

Description

Apparatus and Method for Driving Organic Electro Luminescence Display

1 is a view showing a structure according to an embodiment of a conventional passive matrix organic light emitting device.

2 is a view showing a structure according to another embodiment of a general passive matrix organic light emitting device.

3 is a view showing the structure of a passive matrix organic light emitting device according to a first embodiment of the present invention.

4 is a view showing the structure of a passive matrix organic light emitting device according to a second embodiment of the present invention.

5 is a view showing the structure of a passive matrix organic light emitting device according to a third embodiment of the present invention.

6 is a view showing a fourth embodiment in which the voltage transfer circuit shown in FIG. 3 is modified.

7 is a view showing a fifth embodiment in which the voltage transfer circuit shown in FIG. 3 is modified.

8 illustrates a structure of a passive matrix organic light emitting diode according to a sixth embodiment of the present invention.

9 to 11 illustrate a method of driving a passive matrix organic light emitting device according to a first embodiment of the present invention.

12 illustrates a structure of a passive matrix organic light emitting diode according to a seventh embodiment of the present invention.

13 to 15 illustrate a method of driving a passive matrix organic light emitting diode according to a seventh embodiment of the present invention.

16 illustrates a structure of a passive matrix organic light emitting diode according to an embodiment of the present invention including a dummy scan electrode line.

FIG. 17 is a view illustrating current waveforms of pixels and scan pulses of scan electrode lines in the organic light emitting diode of FIG. 16; FIG.

<Description of the symbols for the main parts of the drawings>

10, 11: scan electrode line driver 12: potential difference generator

14: data electrode line driver 16: discharge unit

18: EL cell 20: panel

22: resistance row 28: dummy scan electrode line

36: current source 40: voltage transfer circuit

50: first power supply 52: second power supply

64, 66: dummy scan electrode line

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting device, and more particularly, to an apparatus and a driving method of an organic light emitting device capable of improving image quality by reducing a comb-tooth pattern and cross-talk effect.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include Liquid Crystal Display, Field Emission Display, Plasma Display Panel, and Electro-Luminescence. ) Display devices. Among these, an electroluminescent display device is a self-luminous device that emits a fluorescent material by recombination of electrons and holes, and is classified into an inorganic light emitting device and an organic light emitting device according to its material and structure. Compared to the passive light emitting device requiring a separate light source such as a liquid crystal display, such an electro-luminescence display device has a fast response speed at the same level as a cathode ray tube, and has a low DC driving voltage and an ultra thin film. It has the advantage of being portable.

FIG. 1 illustrates a passive matrix organic light emitting diode (PMOLED) of the organic light emitting diode, and the organic light emitting diode includes an intersection portion between scan electrode lines S1 -Sn and data electrode lines D1 -Dm. EL cells 2 arranged every time are provided. Each of the EL cells 2 is selected when a scan pulse is applied to the scan electrode lines S1 to Sn, which are cathodes, to generate light corresponding to a pixel signal, that is, a current signal, supplied to the data electrode line, which is a cathode. Each of the EL cells 2 is formed at each intersection of the data electrode line and the scan electrode lines S1 to Sn and is equivalently represented by a diode.

Each of these EL cells 2 is supplied with the scan pulses of the negative polarity generated from the scan electrode line driver 4 to the scan electrode lines S1 to Sn, and at the same time according to the data signal generated from the data electrode line driver 6. A positive current is applied to the data electrode line to emit light when a forward voltage is applied. In this case, the reverse direction voltage is applied to the EL cells 2 included in the scan electrode lines S1 to Sn that are not selected, so that they do not emit light. In other words, the EL cells 2 that emit light are charged with the forward charge while the EL cells 2 that do not emit the light are charged with the reverse charge.

However, in the passive organic light emitting device as illustrated in FIG. 1A, since a resistive component is present in the scan electrode lines S1 to Sn, a luminance difference occurs in one scan electrode line as shown in FIG. 1B. When displayed on the panel 8, the screen becomes uneven. That is, EL disposed on one scan electrode line S1 to Sn by a resistance component present in the scan electrode lines S1 to Sn and a current flowing through the scan electrode line in one scan electrode line S1 to Sn. The potential difference is generated between the cells 2, so that the EL cells 2 far from the scan electrode line driver 4 are darker than the EL cells 2 having a shorter distance.

As shown in FIG. 2A, the scan electrode line driver 4 is disposed on both sides of the panel 8, and the scan electrode lines S1 to Sn are alternately connected to either of the scan electrode line driver 4 on both sides. The driving device has been presented, but the driving device has an advantage that the display screen is located at the center of the panel 8, but it is even with the odd-numbered scan electrode lines S1, S3, ..., Sn-1. Since the direction in which the first scan electrode line S2, S4, ..., Sn is connected is different, as shown in FIG. 2B, the light and dark portions in one scan electrode line S1 to Sn are each line. There is a problem that the comb pattern effect that occurs alternately every time occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and an organic light emitting device capable of improving the uniformity of a display screen by generating a potential difference corresponding to a potential difference generated on a scan electrode line and precharging the generated potential difference to a data electrode line. It is a technical object of the present invention to provide a driving device and a driving method.

In addition, the present invention improves the uniformity of the display screen by additionally installing a dummy scan electrode line on the panel to solve the above problems and applying a scan pulse to the dummy scan electrode line during the period before the scan electrode line is stabilized Another object of the present invention is to provide a driving device and a driving method of an organic light emitting device.

An organic light emitting device driving apparatus according to an aspect of the present invention for achieving the above object is a scan electrode line driver for sequentially applying a negative scan pulse to a plurality of scan electrode lines, and the plurality of scan electrode lines A potential difference generator that generates a potential difference corresponding to the potential difference to be generated on any one of the scan electrode lines, and the potential difference generator generates a potential difference by applying a predetermined current to the potential difference generator, and generates the potential difference as a data electrode. And a data electrode line driver for precharging the data electrode lines by applying them to a line, and supplying a predetermined current to the plurality of data electrode lines to emit light of the EL cells.

In an embodiment, the potential difference generator is connected to both ends of the resistor string and the resistor string equalizing resistors present in any one of the plurality of scan electrode lines and alternately grounds one end of the resistor string. A first and a second switch configured as first and second switches or connected to both ends of the dummy scan electrode line and the dummy scan electrode line having the same characteristics as the scan electrode line, and alternately grounding one end of the dummy scan electrode line; It consists of 2 switches.

A data source for driving a predetermined current to the potential difference generator or the data electrode line; a third switch for selectively connecting one of the potential difference generator or the data electrode line to the current source; And a voltage transfer unit configured to transfer the potential difference generated by the generation unit to the data electrode line, and a fourth switch configured to selectively connect the voltage transfer unit and the data electrode line to precharge the data electrode line.

On the other hand, the driving device of the organic light emitting device may further include a discharge unit for discharging the charges stored in the EL cell due to the application of a current corresponding to the previous data signal, wherein the discharge unit is stored in the EL cell A common discharge line having one end connected to a ground point so that the existing charges can be discharged, and the common discharge line and the respective data electrode line so that when stored, the charge stored in the EL cell can be discharged to the common discharge line. It is composed of a plurality of fifth switches connected between.

According to another aspect of the present invention, there is provided a method of driving an organic light emitting device, by applying a predetermined current to a potential difference generating unit to a potential difference generated on any one of the plurality of scan electrode lines. Generating a corresponding potential difference, precharging the EL cells by transferring a potential difference generated by the potential difference generator to a data electrode line by using a predetermined voltage transfer circuit, and a predetermined voltage to the data electrode line Illuminating the EL cells by applying a driving current corresponding to the data signal.

The organic light emitting device driving apparatus according to another aspect of the present invention for achieving the above object is a scan electrode line driver for sequentially applying a scan pulse to the plurality of scan electrode lines, and using a separate power supply A potential difference generator for generating a potential difference corresponding to a potential difference generated on any one of a plurality of scan electrode lines, and applying the potential difference generated by the potential difference generator to the data electrode line; And a data electrode line driver for precharging a line and supplying a predetermined current to the plurality of data electrode lines to emit light of the EL cells, wherein the potential difference generator is one of the plurality of scan electrode lines. Equalization of the resistors present in the And a power supply unit for supplying a voltage or a current to the resistor row to generate a potential difference between the resistor row formed of the resistor and the resistors disposed in the resistor row.

According to another aspect of the present invention, there is provided a driving apparatus of an organic light emitting device, wherein a plurality of scan electrode lines and a plurality of data electrode lines and an EL disposed at intersections of the plurality of scan electrode lines and data electrode lines are provided. An apparatus for driving an organic light emitting device including cells, the apparatus comprising: at least one dummy scan electrode line; A scan electrode line driver for applying a scan pulse to the dummy scan electrode line and applying a scan pulse to a first scan electrode line to be displayed among the plurality of scan electrode lines after a predetermined time elapses; And a data electrode line driver supplying a predetermined current to the plurality of data electrode lines to emit light of the EL cells. Characterized in that it comprises a.

According to another aspect of the present invention, there is provided a method of driving an organic light emitting device including a dummy scan electrode line, comprising: applying a scan pulse to the dummy scan electrode line; Applying a current corresponding to a predetermined data signal to an EL cell on the dummy scan electrode line through a data electrode line; And applying a scan pulse to the first scan electrode line to be actually displayed after a predetermined time passes so that a current corresponding to the predetermined data signal is applied to the EL cell on the first scan electrode line. Illuminating the cell; Characterized in that it comprises a.

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

3 shows an apparatus for driving an organic light emitting diode according to a first embodiment of the present invention. As shown, the driving device of the organic light emitting element includes the scan electrode line driver 10 and 11, the potential difference generator 12, the data electrode line driver 14, the discharge unit 16, and the plurality of EL cells 18. It comprises a panel 20 consisting of.

The scan electrode line drivers 10 and 11 select the scan electrode lines S1 to Sn to display data by sequentially applying negative scan pulses to the plurality of scan electrode lines S1 to Sn. In order to be located at the center of the panel 20, the scan electrode line driving units 10 and 11 are composed of two. Odd-numbered scan electrode lines S1, S3,..., Sn-1 are connected to the first scan electrode line driver 10, and even-numbered scan electrode lines S2 are connected to the second scan electrode line driver 11. S4, ..., Sn) are connected. Of course, even-numbered scan electrode lines S2, S4, ..., Sn are connected to the first scan electrode line driver 10, and odd-numbered scan electrode lines S1, S3 are connected to the second scan electrode line driver 11, of course. It is obvious that it is possible to connect, ..., Sn-1).

The potential difference generator 12 is provided in the data electrode line driver 14 to estimate the potential difference generated on the scan electrode lines S1 to Sn. The potential difference generator 12 includes a resistor row 22 and first and second switches 24 and 26 connected to both ends of the resistor row 22, and the resistor row 22 includes a scan electrode line ( Equivalent of the resistors present in any one of the scan electrode line of S1 ~ Sn, and composed of a plurality of resistors connected in series with each other, the first switch and the second switch (24, 26) is a scan electrode line (S1) Alternately on and off in response to the driving of ˜Sn), the resistance train 22 is selectively connected to the ground point.

Specifically, when the first scan electrode line driver 10 is driven to apply the scan pulse to the odd-numbered scan electrode line, the first switch 24 is turned on and the second switch 26 is turned off to form the resistance string 22. When the left side of) is connected to the ground point, and the second scan electrode line driver 11 is driven to apply a scan pulse to the even scan electrode line, the second switch 26 is turned on and the first switch 24 is turned on. Off, the right side of the resistor row 22 is connected to the ground point.

Since the resistance constituting the resistance row 22 is equivalent to the resistance present in any one of the scan electrode lines S1 to Sn, the potential difference generated in the resistance row 22 is the scan electrode line S1 to. Since the potential difference is almost equal to that generated on Sn, the potential difference generated on the scan electrode lines S1 to Sn can be expected.

In the above-described embodiment, although the potential difference generator 12 is described as being implemented by the resistor string 22 and the first and second switches 24 and 26, in the second embodiment, the embodiment is a modified embodiment. In order to more accurately predict the potential difference generated on the scan electrode lines S1 to Sn, as shown in FIG. 4, the potential difference is generated by using the same scan electrode line 28 as the dummy scan electrode lines S1 to Sn as a dummy. Part 12 may be implemented. That is, the potential difference generator 12 is implemented by the first and second switches 24 and 26 connected to both ends of the dummy scan electrode line 28 and the dummy scan electrode line 28. In this case, the potential difference generator 12 is formed on the panel 20 of the organic light emitting diode, and is preferably disposed at the top of the scan electrode lines S1 to Sn. In this case, the EL cells 30 disposed on the dummy scan electrode line 28 emit light due to the current supplied on the dummy scan electrode line 28, and thus correspond to a region where the dummy scan electrode line 28 is disposed. It is preferable to block the light emitted by installing a light shield or the like on the panel area to be irradiated with ultraviolet (UV).

In addition, in the above-described first and second embodiments, the first and second switches 24 and 26 are described as being connected to the ground point. In the third embodiment, the potential difference is more accurately shown in FIG. As shown, a resistor 32 and a zener diode 34 may be connected in series between the first switch and the second switch 24 and 26 and the ground point. Here, the resistor 32 connected to the first and second switches 24 and 26 is a resistor 36 present on a line connecting the scan electrode lines S1 to Sn and the scan electrode line drivers 10 and 11. Is equivalent to Further, in another embodiment in which the above embodiments are modified, a voltage source capable of supplying a voltage of a predetermined magnitude may be connected to one end of the first and second switches. In the above embodiments, the resistor 32, the zener diode 34, and the voltage source may be formed in the potential difference generator 12, but may be formed separately from the potential difference generator 12.

Referring back to FIG. 3, the data electrode line driver 14 includes the potential difference generator 12 in the potential difference generator 12 by applying a predetermined current to the potential difference generator 12. A potential difference is generated in the formed resistance row 22, the generated potential difference is applied to the data electrode lines D1 to Dm to precharge the data electrode lines D1 to Dm, and the precharged data electrode line ( The EL cells 18 emit light by supplying a predetermined current to D1 to Dm.

Switching operation of the third switch 38 selectively connects the potential difference generator 12 and the data electrode lines D1 to Dm to the current source 36 in the current source 36 included in the data electrode line driver 14. A predetermined current is applied to the potential difference generator 12 and the data electrode lines D1 to Dm through the potential difference generator 12 to generate a potential difference or to emit the EL cells 18.

The voltage transfer unit 40 precharges the data electrode lines D1 to Dm by applying the potential difference generated by the potential difference generation unit 12 to the data electrode lines D1 to Dm. It can be implemented with AMP. As the fourth embodiment and the fifth embodiment, the embodiment is modified, as shown in FIG. 6, the voltage transfer circuit may be implemented by NMOS or PMOS, and as illustrated in FIG. 7, by a comparator and a PMOS. May be The voltage transfer unit 40 is connected to the data electrode lines D1 to Dm through the fourth switch 42. The fourth switch 40 is a current for gray scale expression through the data electrode lines D1 to Dm. Is turned on only before the supplied period to precharge the data electrode lines D1 to Dm.

The discharge unit 16 discharges the electric charges stored in the EL cells 18 due to the application of a current corresponding to the previous data signal, and the common discharge line 44 and the plurality of fifth switches in which the electric discharges are discharged. And the fifth switches 46 are connected between the common discharge line 44 and the respective data electrode lines D1 to Dm, and one end of the common discharge line 44 is a ground point. Is connected to. In this case, the discharge unit 16 is preferably formed in the data electrode line driver 14. As a sixth embodiment, the embodiment is a modified embodiment, as shown in FIG. 8 to prevent power consumption, a zener diode 48 is connected between one end of the common discharge line 44 and a ground point, or shown. Although not, it is possible to prevent the discharge to occur below a predetermined voltage by connecting a voltage source capable of supplying a voltage of a predetermined magnitude to one end of the common discharge line. In this case, the zener diode 48 or the voltage source may be formed in the discharge unit 16 or may be formed outside the discharge unit 16.

The driving method of the organic light emitting diode according to the first to sixth embodiments of the present invention described above will be described in detail with reference to FIGS. 9 to 11.

First, FIG. 9 illustrates that potential difference generation and discharge are performed. As shown in FIG. 9, the plurality of fifth switches 46 provided in the discharge unit 16 are all turned on and previously applied to the EL cells 18. Discharged charges are discharged through the common discharge line 44. At the same time, the third switch 38 connects the current source 36 and the potential difference generator 12 so that current is applied to the potential difference generator 12 so as to actually scan the resistance row 22 of the potential difference generator 12. A potential similar to that generated when driving the electrode line is generated.

At this time, the first and second switches 24 and 26 connected to both ends of the resistance string 22 are first or second scanned to generate a potential difference between the resistors constituting the resistance string 22 of the potential difference generator 12. It is turned on and off in accordance with the driving timing of the electrode line drivers 10 and 11. Specifically, odd-numbered scan electrode lines S1, S3,..., And Sn-1 are connected to the first scan electrode line driver 10, and even-numbered scans are connected to the second scan electrode line driver 11. When the electrode lines S2, S4,..., Sn are connected, when the first scan electrode line driver 10 is driven, the first switch 24 is turned on to be connected to the ground point, and the second switch ( 26 is turned off. When the second scan electrode line driver 11 is driven, the second switch 26 is turned on to be connected to the ground point, and the first switch 24 is turned off.

Next, FIG. 10 illustrates precharging of the data electrode line by applying the generated potential difference to the data electrode line. As shown in FIG. 10, the fourth switch 42 is turned on so that the voltage transfer unit 40 may generate data. The potential difference generated by the potential difference generator 12 is applied to the data electrode lines D1 to Dm by being connected to the electrode lines D1 to Dm to precharge the data electrode lines D1 to Dm. At the same time as the fourth switch 42 is turned on, all of the fifth switches 46 included in the discharge unit 16 are turned off so that no further discharge occurs.

FIG. 11 is a view showing the EL cells emitting light by applying a current corresponding to the data signal to the EL cells after the precharging period. The current is generated by connecting the third switch 38 to the data electrode lines D1 to Dm. The EL cells 18 are lighted by being applied to the electrode lines D1 to Dm, and the remaining first, second, fourth, and fifth switches 24, 26, 42, and 46 are turned off.

Meanwhile, in the first to sixth embodiments, the potential difference generator 12 receives the predetermined current from the current source 36 included in the data electrode line driver 14, thereby providing each of the resistor rows 22. Although it has been described as generating a potential difference between the resistors, in the seventh embodiment in which the above embodiments are modified, a potential difference is generated between the resistors by receiving a current or a voltage through a power supply unit provided in the potential difference generator 12. You can.

Specifically, referring to FIG. 12, first, the potential difference generator 12 includes a resistor row 22 and a power supply unit 50 and 52 disposed at both ends of the resistor row, and the power supply units 50 and 52 are provided. Selectively connects one of the first current source 54 and the first voltage source 58 to the first and second current sources 54 and 56, the first and second voltage sources 58 and 60, and the resistor string 22. And a second switch 26 for selectively connecting any one of the second current source 56 and the second voltage source 60 to the resistance row 22.

In the case of the present embodiment, since the separate power supply units 50 and 52 are provided in the potential difference generator 12, the data electrode line driver 14 does not need to receive current from the data electrode line driver 14. The third switch 38 selectively connects only the current source 36 and the data electrode lines D1 to Dm, and the data electrode line driver 14 transfers the voltage difference generated by the potential difference generator 12 to the voltage transfer device. A further sixth switch 62 is further provided to selectively connect the potential difference generator 12 and the voltage transfer part 40 to the part 40.

In the above-described embodiment, the switching operation of the first and second switches 24 and 26 is determined according to the driving of the scan electrode lines S1 to Sn, which will be described in detail with reference to FIG. 12. First, when the first scan electrode line driver 10 is driven to apply a scan pulse to the odd-numbered scan electrode lines S1, S3,..., Sn-1, the first switch 24 is configured as a first current source. And the second switch 26 connect the second voltage source 60 to the resistor row 22, and the second scan electrode line driver 11 is driven to be even. When a scan pulse is applied to the scan electrode lines S2, S4,..., And Sn, the second switch 26 connects the second current source 56 and the resistor string 22 to each other. 24 connects the first voltage source 58 to the resistor row 22.

As a modified embodiment, the first scan electrode line driver 10 is driven so that the scan pulse is applied to the odd-numbered scan electrode lines S1, S3, ..., Sn-1. The switch 24 connects the first voltage source 58 and the resistor string 22, the second switch 26 connects the second current source 56 to the resistor string 22, and the second scan electrode line driver. When the driving pulse 11 is driven and the scan pulse is applied to the even-numbered scan electrode lines S2, S4, ..., Sn, the second switch 26 connects the second voltage source 60 and the resistor string 22 to each other. The first switch 26 may connect the first current source 54 to the resistor row 22.

A driving method of the organic light emitting diode according to the seventh embodiment will be described in detail with reference to FIGS. 13 to 15.

First, FIG. 13 shows that potential difference generation and discharge are performed. As shown in FIG. 13, the plurality of fifth switches 46 provided in the discharge unit 16 are all turned on and previously applied to the EL cells 18. Discharged charges are discharged through the common discharge line 44. At the same time, the first and second switches 24 and 26 of the power supply units 50 and 52 provided in the potential difference generator 12 are connected to the current source 54 or 56 or the voltage source 58 and 60 and the resistor string 22. By connecting the two to the resistance row 22 of the potential difference generating unit 12 so as to generate a potential similar to the potential generated when driving the scan electrode line.

At this time, the first and second switches 24 and 26 connected to both ends of the resistance string 22 are first or second scanned to generate a potential difference between the resistors constituting the resistance string 22 of the potential difference generator 12. The switching is performed according to the driving timing of the electrode line drivers 10 and 11. Specifically, odd-numbered scan electrode lines S1, S3,..., And Sn-1 are connected to the first scan electrode line driver 10, and even-numbered scans are connected to the second scan electrode line driver 11. When the electrode lines S2, S4,..., And Sn are connected, when the first scan electrode line driver 10 is driven, the first switch 24 is connected to the first current source 54 and the resistance train ( 22) and the second switch 26 connects the second voltage source 60 and the resistor string 22. When the second scan electrode line driver 11 is driven, the second switch 26 is connected to the second switch 26. The current source 56 is connected to the resistor row 22, and the first switch connects the first voltage source 58 and the resistor row 22.

Next, FIG. 14 illustrates precharging of the data electrode line by applying the generated potential difference to the data electrode line. As shown in FIG. 14, the sixth switch 62 is turned on so that the potential difference generator 12 and the voltage are turned on. The potential difference generated by the potential difference generator 12 is connected to the data electrode by connecting the transfer unit 40 and the fourth switch 42 to be turned on to connect the voltage transfer unit 40 and the data electrode lines D1 to Dm. The data electrode lines D1 to Dm are precharged by being applied to the lines D1 to Dm. At this time, it is preferable that all of the fifth switches 46 included in the discharge unit 16 are turned off so that no further discharge occurs.

FIG. 15 is a view showing the EL cells emitting light by applying a current corresponding to the data signal to the EL cells after the precharging period. The first, second, fourth, fifth, and sixth switches 24, 26, and 42 are shown in FIG. , 46 and 62 are all turned off, and the third switch 38 connects to the data electrode lines D1 to Dm so that current is applied to the data electrode lines D1 to Dm to emit the EL cells 18. .

Meanwhile, in the above-described embodiments, the comb pattern and the crosstalk generated in the organic light emitting diode are removed by using the potential difference predicted by the potential difference generator. However, in the modified embodiment, the dummy scan electrode on the panel is removed. By adding only the lines, you can remove the comb or cross talk. This embodiment will be described in detail with reference to FIGS. 16 and 18.

First, FIG. 16A illustrates a structure of a passive matrix organic light emitting diode according to an embodiment of the present invention including a dummy scan electrode line. As shown, the panel 20 according to the present embodiment further includes a dummy scan electrode line 64 in addition to the scan electrode lines S1, S2,..., Sn.

In the driving device of the organic light emitting diode including the dummy scan electrode line 64, the scan electrode line driving units 10 and 11 are dummy until the scan electrode lines S1, S2,..., Sn are stabilized. By applying the scan pulse to the scan electrode line 64, the current corresponding to the data signal applied to the data electrode lines D1, D2, ..., Dn is transferred to the EL cell 18 on the dummy scan electrode line 64. To be applied to In addition, after the scan electrode lines S1, S2, ..., Sn are stabilized, a scan pulse is applied to each scan electrode line to be displayed to the data electrode lines D1, D2, ..., Dn. A current corresponding to the data signal to be applied is applied to the EL cells 18 on each scan electrode line to be displayed.

As a result, the comb-tooth pattern or the crosstalk effect due to the potential difference generated on one scan electrode line can be prevented. When a scan pulse is applied to the dummy scan electrode line 64, the EL cell 18 on the dummy scan electrode line 64 emits light for a predetermined time, and thus an area in which the dummy scan electrode line 64 is disposed to prevent the scan pulse is applied. It is preferable to block the light emitted by installing a light shield or the like in the panel region corresponding to the ultraviolet rays.

In the above-described embodiment, the dummy scan electrode line is described as being configured as one, but may be configured as two scan electrode lines as shown in FIG. 16B. In this case, when a scan pulse is applied from the first scan electrode line driver 10 to the scan electrode line to be actually displayed, the scan pulse is applied to the first dummy scan electrode line 64 and the scan electrode line to be actually displayed. When a scan pulse is applied from the second scan electrode line supply unit 11, a scan pulse is supplied to the second dummy scan electrode line 66.

FIG. 17 shows the current waveform of the pixel and the scan pulse of the scan electrode line according to the embodiment described above. FIG. 17 (a) shows a current waveform flowing in a pixel, FIG. 17 (b) shows a scan pulse applied to a dummy scan electrode line, and FIG. 17 (c) shows a scan pulse applied to a scan electrode line to be actually displayed. Shows. As shown, since the scan pulse is applied only to the dummy scan electrode line 64 during the period before the actual scan electrode line to be stabilized, the EL cell on the dummy scan electrode line 64 is supplied with a current corresponding to the predetermined data signal. Is only applied. In the section after the scan electrode line to be actually displayed is stabilized, the dummy scan electrode line 64 is turned off and the scan electrode line to be actually displayed is turned on so that the scan pulse is applied only to the scan electrode line to be actually displayed so that the scan electrode line is actually displayed. The EL cell 18 on the top is made to emit light.

Those skilled in the art to which the present invention pertains will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. For example, in the above-described embodiment, since the scan electrode line driver includes two scan electrodes line drivers, the potential difference generator includes the first and second switches. However, as a modified embodiment, the scan electrode line driver includes one scan electrode line driver. The first and second switches are implemented as a single switch, and are connected to a side to which a voltage is applied to the scan electrode line, either end of the resistor string or the dummy scan electrode line.

Therefore, it is to be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

As described above, according to the present invention, a potential difference corresponding to the potential difference to be generated in the actual scan electrode line is generated by using the potential difference generation unit, and the generated potential difference can be precharged in the data electrode line so as to be placed on one scan electrode line. It is possible to reduce the luminance difference generated.

In addition, according to the present invention, by reducing the difference in luminance generated on one scan electrode line, it is possible to remove the comb and cross-talk, thereby improving the uniformity of the display screen.

Further, according to the present invention, a dummy scan electrode line is additionally installed on the panel, and a current corresponding to a predetermined data signal is applied to the EL cell on the dummy scan electrode line until the scan electrode line to be actually displayed is stabilized, thereby forming a comb pattern and The uniformity of the display screen can be improved by removing the cross talk.

Claims (28)

An apparatus for driving an organic light emitting device, comprising: a panel comprising a plurality of scan electrode lines, a plurality of data electrode lines, and EL cells disposed at intersections of the plurality of scan electrode lines and data electrode lines; A scan electrode line driver sequentially applying scan pulses to the plurality of scan electrode lines; A potential difference generator for generating a potential difference corresponding to a potential difference to be generated on any one of the plurality of scan electrode lines; And The potential difference generator generates a potential difference by applying a predetermined current to the potential difference generator, precharges the data electrode line by applying the generated potential difference to the plurality of data electrode lines, and emits the EL cells. A data electrode line driver supplying a predetermined current to the plurality of data electrode lines; Driving device for an organic light emitting device comprising a. The method of claim 1, wherein the potential difference generator A resistor string that equalizes the resistors present in the scan electrode line; And First and second switches connected to both ends of the resistor row to alternately ground one end of the resistor row; Driving device for an organic light emitting device comprising a. The driving device of claim 2, wherein the potential difference generator is formed in the data electrode line driver. The method of claim 1, wherein the potential difference generator A dummy scan electrode line having characteristics identical to those of the scan electrode line; And First and second switches connected to both ends of the dummy scan electrode line to alternately ground one end of the dummy scan electrode line; Driving device for an organic light emitting device comprising a. The driving device of claim 4, wherein the potential difference generator is formed in a panel. 5. The method of claim 2, wherein the first switch and the second switch are turned on or off when the voltage is applied from the left side according to the direction in which the voltage is applied to the scan electrode line. The switch is turned off, the driving device of the organic light emitting device, characterized in that when the voltage is applied from the right side, the second switch is turned on and the first switch is turned off. The method of claim 2 or 4, wherein the potential difference generating unit First and second resistors connected to one end of the first and second switches, the first and second resistors having the same resistance value as that of the resistance component present on the line connecting the scan electrode line driver and the scan electrode line; And A zener diode connected between the first and second resistors and a ground point; Driving device for an organic light-emitting device further comprises. The data electrode line driver of claim 1, wherein the data electrode line driver is disposed. A current source for supplying a predetermined current to the potential difference generator or the data electrode line; A third switch selectively connecting one of the potential difference generator or the data electrode line to the current source; A voltage transfer unit configured to transfer the potential difference generated by the potential difference generator to the data electrode line; And A fourth switch configured to selectively connect the voltage transfer part and the data electrode line to precharge the data electrode line; Driving device for an organic light emitting device comprising a. The driving device of claim 8, wherein the voltage transfer circuit is implemented by OP-AMP. The driving device of claim 8, wherein the voltage transfer circuit comprises a comparator and a PMOS. The organic light emitting device driving apparatus of claim 1, wherein the driving device of the organic light emitting device further comprises a discharge unit for discharging electric charges stored in the EL cell due to the application of a current corresponding to a previous data signal. Device. The method of claim 11, wherein the discharge unit A common discharge line having one end connected to a ground point so that electric charges stored in the EL cell can be discharged; And A plurality of fifth switches connected between the common discharge line and each of the data electrode lines so that the charge stored in the EL cell can be discharged to the common discharge line when turned on; Driving device for an organic light emitting device comprising a. The method of claim 12, wherein the discharge unit And a Zener diode connected between one end of the common discharge line and a ground point to prevent discharge under a predetermined voltage. An apparatus for driving an organic light emitting device, comprising: a panel comprising a plurality of scan electrode lines, a plurality of data electrode lines, and EL cells disposed at intersections of the plurality of scan electrode lines and data electrode lines; A scan electrode line driver sequentially applying scan pulses to the plurality of scan electrode lines; A potential difference generator for generating a potential difference corresponding to a potential difference generated on any one of the plurality of scan electrode lines by using a separate power supply unit; And A data electrode line driver for precharging the data electrode lines by applying the potential difference generated by the potential difference generator to the data electrode lines, and supplying a predetermined current to the plurality of data electrode lines to emit the EL cells; Driving device for an organic light emitting device comprising a. The method of claim 14, wherein the potential difference generator A resistor string comprising a plurality of resistors connected in series as equivalents of the resistors present in any one of the plurality of scan electrode lines; And A power supply unit supplying a voltage or a current to the resistor row to generate a potential difference between the resistors disposed in the resistor row; Driving device for an organic light emitting device comprising a. The driving device of claim 15, wherein the power supply unit comprises a first power supply unit and a second power supply unit and is disposed at both ends of the resistor string. The method of claim 16, wherein the first power supply unit, A first current source for supplying current to the resistance heat; A first voltage source supplying a voltage to the resistance column; And A first switch for selectively connecting the first current source and the first voltage source to the resistor string; Includes, the second power supply unit, A second current source for supplying current to the resistance heat; A second voltage source supplying a voltage to the resistance column; And A second switch for selectively connecting the second current source and the second voltage source to the resistor string; Driving device for an organic light emitting device comprising a. The method of claim 17, wherein the first and second switches connect the first current source to the resistor string when the voltage is applied from the left side in the direction in which the voltage is applied to the scan electrode line. A switch connects a second voltage source to the resistor string, and when a voltage is applied from the right side, the first switch connects the first voltage source to the resistor string and the second switch connects a second current source to the resistor string. Driving device for an organic light emitting device. The method of claim 17, wherein the first and second switches connect the first voltage source to the resistor string when the voltage is applied from the left side in the direction in which the voltage is applied to the scan electrode line. A switch connects a second current source to the resistor string, and when a voltage is applied on the right side, the first switch connects the first current source to the resistor string and the second switch connects a second voltage source to the resistor string. Driving device of organic light emitting element. 15. The method of claim 14, wherein the data electrode line driver A current source for supplying a predetermined current to the data electrode line; A voltage transfer unit configured to transfer the potential difference generated by the potential difference generator to the data electrode line; A third switch connecting the current source and the data electrode line to emit light of the EL cells; A fourth switch configured to selectively connect the voltage transfer unit and the data electrode line to precharge the data electrode line; And A sixth switch connecting the potential difference generator and the voltage transmitter to transfer the potential difference generated by the potential difference generator to the voltage transmitter; Driving device for an organic light emitting device comprising a. A driving apparatus of an organic light emitting device including a plurality of scan electrode lines and a plurality of data electrode lines, and EL cells arranged at intersections of the plurality of scan electrode lines and data electrode lines. At least one dummy scan electrode line; A scan electrode line driver for applying a scan pulse to the dummy scan electrode line and applying a scan pulse to a first scan electrode line to be actually displayed among the plurality of scan electrode lines after a predetermined time elapses; And A data electrode line driver supplying a predetermined current to the plurality of data electrode lines to emit light of the EL cells; Driving device for an organic light emitting device comprising a panel comprising a. The driving device of claim 21, wherein the predetermined time is a time required for the first scan electrode line to stabilize. A driving method of an organic light emitting device including a plurality of scan electrode lines and a plurality of data electrode lines, and an EL cell disposed at an intersection point of the plurality of scan electrode lines and a data electrode line. Generating a potential difference corresponding to a potential difference generated on any one of the plurality of scan electrode lines by applying a predetermined current to the potential difference generating unit; Precharging the EL cells by transferring a potential difference generated by the potential difference generator to the data electrode line using a predetermined voltage transfer circuit; And Emitting light of the EL cells by applying a driving current corresponding to a predetermined data signal to the data electrode line; Method of driving an organic light emitting device comprising a. 24. The method of claim 23, further comprising discharging electric charges previously stored in the EL cells before the potential difference predicting step. The method of claim 24, And the charge discharging step and the potential difference estimating step are performed at the same time. 25. The method of claim 24, wherein the discharging step ends before the precharging step and the precharging step ends before the EL cell light emitting step. A method of driving an organic light emitting device including a dummy scan electrode line, Applying a scan pulse to the dummy scan electrode line; Applying a current corresponding to a predetermined data signal to an EL cell on the dummy scan electrode line through a data electrode line; And The EL cell on the first scan electrode line by applying a scan pulse to the first scan electrode line to be actually displayed after a predetermined time so that a current corresponding to the predetermined data signal is applied to the EL cell on the first scan electrode line. Emitting light; Method of driving an organic light emitting device comprising a. 28. The method of claim 27, wherein the predetermined time is a time required for the first scan electrode line to stabilize.

Images