KR20080095461A - Organic light emitting display and driving mothod thereof - Google Patents

Abstract

An organic light emitting display and a driving method thereof are provided to correct brightness change due to deterioration and temperature variation of an organic light emitting diode by using a pixel used for displaying a screen. An organic electroluminescence panel includes a data driving unit and a plurality of pixel circuits. A power supply(120) is electrically connected to the organic electroluminescence panel. At least one sensor pixel(130) is selected at the pixel circuit of the organic electroluminescence panel. A controller(140) is electrically connected to the sensor pixel. The controller provides a constant current to the sensor pixel and compensates for the voltage of the power supply.

Description

Organic electroluminescent display and driving method thereof {Organic Light Emitting Display and Driving Mothod Thereof}

1A and 1B illustrate conceptual diagrams for explaining changes in luminance due to deterioration of an organic light emitting diode of an organic light emitting display device.

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

3 illustrates a configuration of a general pixel circuit of an organic light emitting display device according to an embodiment of the present invention.

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

5 is a block diagram schematically illustrating an organic light emitting display device according to another exemplary embodiment of the present invention.

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

100, 200; Embodiment according to the present invention

110; An organic electroluminescent display panel 111; Scan driver

112; A data driver 113; Pixel circuit

120; A power supply 130; Sensor pixel

140; Control unit 141; Constant current supply

142; Sensor unit 143; Voltage storage

144; Voltage compensator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device and a driving method thereof, and more particularly, to an organic light emitting display device capable of correcting a luminance change due to deterioration and temperature change of an organic light emitting device. The present invention relates to an electroluminescent display and a driving method thereof.

An organic light emitting display device is a display device for electrically exciting a fluorescent or phosphorescent organic compound to emit light, and is capable of displaying an image by driving N × M organic light emitting diodes (OLEDs).

Referring to FIG. 1A, these organic light emitting cells have a structure of an anode (ITO), an organic thin film, and a metal (metal). The organic thin film has a multilayer structure including an emission layer, an electron transport layer (ETL), a hole transport layer (HTL), and a separate electron injecting layer (EIL). It may include a hole injecting layer (HIL).

Referring to FIG. 1B, since the voltage applied to the anode electrode is always set higher than the voltage applied to the cathode of the organic light emitting diode (OLED), carriers of negative polarity (−) are formed on the anode electrode side. Positive carriers on the cathode electrode side.

If the carriers of negative polarity (-) located in the anode electrode and the carriers of positive polarity (+) located in the cathode electrode are maintained for a long time, the amount of movement of electrons and holes that contribute to light emission is reduced, which reduces the average luminance. It is called brightness reduction by deterioration.

)값이 변화하게 된다. 이것은 전자의 경우,In addition, when the temperature changes, the flow mobility of the transistor (

) Value will change. This is the former case,

This is because it is inversely proportional to the temperature (absolute temperature) by the formula of. Here, the current density J defined as the net charge flow passing through the unit area per unit time is

In the end, the current value is inversely proportional to temperature. Holes are also inversely proportional to temperature in this manner. Therefore, in the organic light emitting diode OLED which emits light by the combination of electrons and holes, the movement of electrons and holes decreases with increasing temperature, resulting in less coupling in the emission layer EML. Will be degraded.

In a typical organic electroluminescent display, when the organic light emitting diode (OLED) deteriorates, a current efficiency change and a current-voltage characteristic change occur. In particular, in the case of the digital driving method of driving the constant voltage, the degree is severely affected by the current-voltage characteristic change. In addition, there is a problem that the luminance is changed by changing the emission current flowing through the organic light emitting diode OLED when the luminance is the same according to the change of the ambient temperature.

In the related art, a dummy pixel is configured in an organic light emitting display panel to correct such a change in luminance, a constant current is applied to the dummy pixel, and the light emitting power voltage ELVDD is applied using the measured voltage value. I've used a modulating way. However, in the conventional method, dummy pixels must be configured in the organic light emitting display panel, and since the configured dummy pixels must actually operate while emitting light, unnecessary components are added to the organic light emitting display panel.

In particular, in the case of the organic light emitting display panel of the top emission type, there is a problem that a screen display irrespective of the image to be displayed is generated as the dummy pixel emits light.

SUMMARY OF THE INVENTION The present invention has been made to overcome the above-described problems, and an object of the present invention is to provide a dummy pixel which is unnecessary for an organic electroluminescent display panel in performing real-time correction of luminance change due to deterioration and temperature change of the organic electroluminescent display. The present invention provides an organic electroluminescent display device and a method of driving the same, which can increase efficiency by using pixels used for actual screen display.

Another object of the present invention is to provide an organic light emitting display device and a method of driving the same, which can freely set a sensing time for correcting a change in luminance of an organic light emitting diode (OLED).

In order to achieve the above object, an organic light emitting display device according to the present invention includes an organic light emitting display panel including a scan driver, a data driver and a pixel circuit, a power supply unit electrically connected to the organic light emitting display panel, At least one sensor pixel selected from a pixel circuit of an organic light emitting display panel and a controller electrically connected to the sensor pixel, wherein the controller supplies a constant current to the sensor pixel and corrects a voltage of the power supply unit. .

The scan driver and the data driver of the organic light emitting display panel may be electrically connected to the pixel circuits other than the sensor pixel.

In addition, the power supply unit may be electrically connected to the pixel circuits other than the sensor pixel.

The control unit may include a constant current supply unit electrically connected to the sensor pixel to supply a current, a sensor unit electrically connected to the sensor pixel to measure a voltage applied to the sensor pixel, and electrically connected to the sensor unit. The voltage storage unit may store a voltage measured by a sensor unit, and a voltage correction unit connected to the voltage storage unit and the power supply unit to correct the voltage of the power supply unit with the voltage stored in the voltage storage unit.

The constant current supply unit may be further electrically connected to the data driver.

In addition, the constant current supply unit may supply a current controlled by the data driver to the sensor pixel.

The sensor unit may measure an applied voltage formed on the organic light emitting diode of the sensor pixel.

The voltage storage unit may be any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory.

The voltage corrector may control a supply voltage of the power supply unit using a voltage value stored in the voltage storage unit.

In addition, an organic light emitting display panel including a scan driver, a data driver, and a pixel circuit, a power supply electrically connected to the organic light emitting display panel, at least one sensor pixel selected from a pixel circuit of the organic light emitting display panel; And a control unit electrically connected to the sensor pixel, wherein the power supply unit and the control unit are complementarily connected to the sensor pixel, and the control unit may supply a constant current to the sensor pixel and correct a voltage of the power supply unit. have.

The organic electroluminescent display panel scan driver and the data driver may be electrically connected to the pixel circuits other than the sensor pixel.

In addition, the power supply unit may be electrically connected to the pixel circuits other than the sensor pixel.

The control unit may include a constant current supply unit electrically connected to the sensor pixel to supply a current, a sensor unit electrically connected to the sensor pixel to measure a voltage applied to the sensor pixel, and electrically connected to the sensor unit. The voltage storage unit may store a voltage measured by a sensor unit, and a voltage correction unit connected to the voltage storage unit and the power supply unit to correct the voltage of the power supply unit with the voltage stored in the voltage storage unit.

The constant current supply unit may be further electrically connected to the data driver.

In addition, the constant current supply unit may supply a current controlled by the data driver to the sensor pixel.

The constant current supply unit may further cause the sensor pixel to emit light when the sensor pixel does not emit light for an effective storage time or more.

In addition, the sensor pixel additionally emits light may be less than one sixteenth of one frame period.

The sensor unit may measure an applied voltage formed on the organic light emitting diode of the sensor pixel.

The voltage storage unit may be any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory.

The voltage corrector may control a supply voltage of the power supply unit using a voltage value stored in the voltage storage unit.

In addition, to achieve the above object, a method of driving an organic light emitting display device according to the present invention includes the steps of: providing an organic light emitting display panel including an organic light emitting display panel including a scan driver, a data driver, and a pixel circuit; A power supply step of supplying a voltage to the organic light emitting display panel by a power supply unit, a sensor pixel driving step of driving a sensor pixel by receiving a constant current by a control unit, and a power supply voltage of the control unit correcting a voltage of the power supply unit And a correction step.

In addition, the scan driver and the data driver of the organic light emitting display panel of the organic light emitting display panel may be electrically connected to the remaining pixel circuits except for the sensor pixel.

In addition, the power supply unit of the power supply step may be electrically connected to the pixel circuits other than the sensor pixel.

The control unit of the sensor pixel driving step may include a constant current supply unit electrically connected to the sensor pixel to supply a current, a sensor unit electrically connected to the sensor pixel to measure a voltage applied to the sensor pixel, and the sensor unit. A voltage storage unit electrically connected to store the voltage measured by the sensor unit, and a voltage correction unit connected to the voltage storage unit and the power supply unit to correct the voltage of the power supply unit with the voltage stored in the voltage storage unit. can do.

The constant current supply unit may be further electrically connected to the data driver.

In addition, the constant current supply unit may supply a current controlled by the data driver to the sensor pixel.

The sensor unit may measure an applied voltage formed on the organic light emitting diode of the sensor pixel.

The voltage storage unit may be any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory.

The voltage corrector may control a supply voltage of the power supply unit using a voltage value stored in the voltage storage unit.

An organic electroluminescent display panel comprising an organic electroluminescent display panel including a scan driver, a data driver, and a pixel circuit, a power supply unit supplying a voltage to the organic electroluminescent display panel, and a sensor A sensor pixel driving step in which a pixel is driven by a constant current supplied by a control unit, a power voltage correction step in which the control unit corrects a voltage of the power supply unit, and the power supply unit is complementarily connected to the control unit to the sensor pixel And a sensor pixel emission step of supplying a voltage to the sensor pixel.

In addition, the scan driver and the data driver of the organic light emitting display panel in the step of providing the organic light emitting display panel may be electrically connected to the remaining pixel circuits except for the sensor pixel.

In addition, the power supply unit of the power supply step may be electrically connected to the pixel circuits other than the sensor pixel.

The control unit of the sensor pixel driving step may include a constant current supply unit electrically connected to the sensor pixel to supply a current, a sensor unit electrically connected to the sensor pixel to measure a voltage applied to the sensor pixel, and the sensor unit. A voltage storage unit electrically connected to store the voltage measured by the sensor unit, and a voltage correction unit connected to the voltage storage unit and the power supply unit to correct the voltage of the power supply unit with the voltage stored in the voltage storage unit. can do.

The constant current supply unit may be further electrically connected to the data driver.

In addition, the constant current supply unit may supply a current controlled by the data driver to the sensor pixel.

The constant current supply unit may further cause the sensor pixel to emit light when the sensor pixel does not emit light for an effective storage time or more.

In addition, the sensor pixel additionally emits light may be less than one sixteenth of one frame period.

The sensor unit may measure an applied voltage formed on the organic light emitting diode of the sensor pixel.

The voltage storage unit may be any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory.

The voltage corrector may control a supply voltage of the power supply unit using a voltage value stored in the voltage storage unit.

As described above, the organic light emitting display device and the driving method thereof according to the present invention measure the voltage value formed in the organic light emitting display element according to the application of a constant current, and correct the voltage value of the power supply unit with the voltage value. It provides a real-time correction of the change in luminance according to deterioration and temperature change of the light emitting device.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily practice the present invention.

Hereinafter, an organic light emitting display device according to an embodiment of the present invention will be described.

2, 3, and 4 are diagrams illustrating a configuration of an organic light emitting display device 100 according to an embodiment of the present invention, a general pixel circuit, and a sensing circuit to which digital driving pixels are applied.

As illustrated in FIG. 2, the organic light emitting display device 100 according to an exemplary embodiment of the present invention includes an organic electroluminescent display panel 110, a power supply unit 120, a sensor pixel 130, and a controller 140. It may include.

The organic light emitting display panel 110 includes a scan driver 111, a data driver 112, and a pixel circuit 113.

The scan driver 111 applies a voltage to the rows of the pixel circuits that emit light among the pixel circuits 113. As a result, the switch transistor connected to the pixel circuit to which the voltage is applied is turned on and the pixel circuit 113 can emit light.

The data driver 112 applies a data voltage value to the pixel circuit 113 selected by the scan driver 111. The pixel circuit 113 includes a driving transistor, and the data driver 112 is electrically connected to a control electrode (gate electrode) of the driving transistor.

Therefore, the gate voltage of the driving transistor control electrode is changed according to the data voltage value of the data driver 112.

Accordingly, the current flowing through the organic light emitting element OLED is controlled. When the current is controlled in the above-described manner, the degree of coupling of electrons and holes in the organic electroluminescent element emission layer is changed, so that the luminance of the organic electroluminescent element is controlled.

In the case of the present invention, a digital driving method is used. The digital driving method (constant voltage driving method) is a method in which the data is applied as a digital signal represented by a binary number instead of an analog. In the case of the digital driving method, the data value of the data driver 112 is applied to 0 or 1 (actually, the voltage applied may be set differently depending on the case). In this case, the organic light emitting diode OLED is turned on and off according to the digital signal, and in this case, the current value flowing through the organic light emitting diode OLED is Measure experimentally. In addition, the adjustment of the brightness may be determined by the time that is turned on for each frame (frame).

Referring to FIG. 3, the pixel circuit 113 generally includes a switching transistor Ma, a driving transistor Mb, a capacitor C, and an organic light emitting diode OLED in an active matrix driving scheme. The control electrode (gate electrode) of the switching transistor Ma is electrically connected to the scan driver 111 and the first electrode (source or drain electrode) is electrically connected to the data driver 112. The control electrode (gate electrode) of the driving transistor Mb is electrically connected to the second electrode of the switching transistor Ma, and the first electrode (sword or drain electrode) of the driving transistor Mb is the power source. It is electrically connected to the electrode ELVDD of the supply unit 120. The capacitor C is electrically connected between the control electrode and the first electrode of the driving transistor Mb. An anode of the organic light emitting diode OLED is electrically connected to a second electrode (drain or source electrode) of the driving transistor Mb. In addition, the cathode of the organic light emitting diode OLED is electrically connected to the electrode ELVSS of the power supply 120.

In the analog driving method, when the switching capacitor Ma is turned on by the scan driver 111, a data voltage is applied to the gate of the driving transistor Mb. Therefore, the equation is defined by the voltage difference between the data voltage applied to the gate of the driving transistor Mb and the power supply voltage applied to the source.

By the current flows. In this formula, V _GS denotes a voltage difference between the control electrode (gate electrode) and the first electrode (source or drain electrode) of the driving transistor Mb, and V _TH is a threshold of the driving transistor Mb. It means the voltage value. In addition, β is a constant representing a value obtained by multiplying electron or hole mobility and capacitance of silicon oxide, and I _OLED denotes a current value flowing through the organic EL device.

In the case of the digital driving method, the voltage of the data driver 112 is fixed to 0 or 1 (the voltage actually applied may be set differently depending on the case). As a result, the current value flowing through the organic light emitting diode OLED for each data is fixed at a constant level. Therefore, the digital driving method uses a method of controlling the light emission time of the organic light emitting display device rather than changing the current value in order to show the luminance difference.

The power supply unit 120 is electrically connected to the scan driver 111, the data driver 112, and the pixel circuit 113 to supply voltage power thereto. In addition, since it is as mentioned above that the electric current value which flows through the said organic electroluminescent element is determined by the said power supply voltage, the following description is abbreviate | omitted.

The sensor pixel 130 is selected from the pixel circuit 113 of the organic light emitting display panel 110. Referring to FIG. 4, the sensor pixel 130 includes a driving transistor Ms, a capacitor Cs, and an organic light emitting display device OLED. The first electrode (source electrode or drain electrode) of the driving transistor Ms is electrically connected to the controller 140, and the second electrode (drain electrode or source electrode) is the organic light emitting display device OLED. It is electrically connected to the anode of. The capacitor Cs is electrically connected between the electrode ELVDD of the power supply 120 and the control electrode (gate electrode) of the driving transistor Ms.

Unlike other pixel circuits, the scan driver 111 and the data driver 112 are not connected to the sensor pixel 130. The controller 140 is electrically connected to the sensor pixel 130. The controller 140 applies a constant current to the sensor pixel 130, and as a result, the sensor pixel 130 emits light.

The sensor pixel 130 is a pixel used for actual screen display. This is different from the conventional method using a dummy pixel. According to the present invention, the efficiency can be improved by using the sensor pixel 130, and in particular, the problem of generating a screen display irrespective of the image to be displayed in the front emission method can be solved.

The controller 140 includes a constant current supply unit 141, a sensor unit 142, a voltage storage unit 143, and a voltage correction unit 144.

The constant current supply unit 141 is electrically connected between the data driver 112 and the sensor pixel 130. The constant current supply unit 141 receives an input of a data value applied to the sensor pixel 130 among the data values of the data driver 112. Then, the value of the constant current to be applied to the sensor pixel 130 is controlled according to the input value. In addition, by applying the controlled constant current to the sensor pixel 130, the sensor pixel 130 may emit light at a desired luminance according to a data value.

The sensor unit 142 is electrically connected to the sensor pixel 130. Referring to FIG. 4, the sensor unit 142 is connected in parallel with the sensor pixel 130 between the constant current supply unit 141 and the electrode ELVSS of the power supply unit 120. The sensor unit 142 performs a function of measuring a voltage formed in the sensor pixel 130 while the sensor pixel 130 emits light.

The voltage storage unit 143 is electrically connected to the sensor unit 142. The voltage storage unit stores a voltage value measured by the sensor unit 142. As the voltage storage unit 143, a voltage memory element (capacitive element) such as a capacitor may be used, and in some cases, a memory element may be used. In this case, the memory device used may be a rewritable erasable PROM (EPROM), an electrically erasable PROM (EEPROM) or a flash memory.

The voltage correction unit 144 is electrically connected between the voltage storage unit 143 and the power supply unit 120. The voltage correction unit 144 corrects the voltage value of the power supply unit 120 with the voltage value stored in the voltage storage unit 143. As a result of this execution, the voltage value of the power supply unit 120 is corrected to the voltage value formed in the sensor pixel 142 which emits light at a desired luminance. Therefore, the luminance change can be corrected without the need to distinguish the luminance change due to deterioration or temperature change of the OLED.

Hereinafter, an organic light emitting display device 200 according to another embodiment of the present invention will be described.

5 illustrates a configuration of an organic light emitting display device 200 according to another embodiment of the present invention.

As illustrated in FIG. 5, the organic light emitting display device 200 according to another exemplary embodiment of the present invention includes a power supply unit 220, a sensor pixel 230, and a controller 240 in addition to the organic light emitting display panel 110. It may further include.

As illustrated, the organic light emitting display device 200 according to another exemplary embodiment of the present invention is substantially the same as the organic light emitting display device 100 described above. Parts having the same configuration and operation have been given the same reference numerals and will be described below with focus on differences.

The power supply 220 is electrically connected to the sensor pixel 230 in addition to the scan driver 111, the data driver 112, and the organic light emitting display element 113, and supplies a power voltage thereto. The difference from the organic light emitting display device 100 described above is that the power supply unit 220 is also electrically connected to the sensor pixel 230. The controller 240 is complementarily connected to the sensor pixel 230. The connection method will be described in the sensor pixel 230 to be described later.

The sensor pixel 230 is complementarily connected to the control unit 240 and the power supply unit 220. This is to control the sensor pixel 230 to emit light through the voltage supply of the power supply 220 instead of the current supply when the sensing time is not performed. That is, the sensor pixel 230 receives a current from the control unit 240 while sensing and emits light by applying a voltage through the power supply unit 220 while not sensing.

5, the switches sw-a1, sw-a2, sw-b are shown. The switches sw-a1 and sw-a2 are simultaneously opened and closed at the same time. In addition, the switch sw-b is complementary to the switches sw-a1 and sw-a2. As a result, the power supply unit 220 and the control unit 241 are complementarily connected to the sensor pixel 230 by the operation of these switches.

When the data in the OFF state is supplied to the sensor pixel 230 for more than an effective storage time, the voltage storage circuit is corrected by additionally emitting light that is indistinguishable to the naked eye.

The effective storage time means the maximum time that the control unit 240 can store the voltage without loss. More specifically, it is a time when a voltage value stored in the voltage storage unit 243, which will be described later, may have a value within a range in which distortion is allowed in correcting the voltage value of the power supply unit 220. For example, when a voltage is stored in a passive element such as a capacitor, the stored voltage value decreases with time due to leakage current. As a result, a distortion of the voltage value occurs, and the stored voltage value can only be used as long as the value is maintained within the allowable range. The amount of distortion allowed is related to the default panel brightness and the like, and also varies depending on the luminance-voltage characteristic of the organic light emitting element OLED. That is, the effective storage time means the maximum time that the voltage can be maintained within this storage voltage distortion degree.

In the digital driving method, when data in an off state is supplied to the sensor pixel 230 for more than an effective storage time, the controller 240 adds one-sixth of a frame period in which the sensor pixel 230 is additionally added. The light emission is performed for the following time. The reason for limiting the upper limit of the additional light emission time is that light emission of the sensor pixel 230 may be detected by the human eye when the additional light emission time exceeds one sixteenth of one frame period. Since this is light emission of pixels irrelevant to the image information, the additional light emission time is limited to the above upper limit. The lower limit is not determined because the sensor pixel 230 must emit light at the time of sensing.

The controller 240 includes a constant current supply unit 241, a sensor unit 242, a voltage storage unit 243, and a voltage correction unit 244.

The constant current supply unit 241 is electrically connected between the data driver 112 and the sensor pixel 230. The constant current supply unit 241 receives a data value of the data driver 112 supplied to the sensor pixel 230 and generates a current according to the value. And it serves to supply this current to the sensor pixel (230).

In addition, the constant current supply unit 241 is connected to the sensor pixel 230 through the switch sw-a1. Therefore, the time that the constant current supply unit applies current to the sensor pixel 230 is during the sensing time. This is different from the organic light emitting display device 100 according to an exemplary embodiment of the present invention, and it is characterized in that the sensing is performed at a predetermined cycle instead of every subframe.

The sensor unit 242 is electrically connected to the sensor pixel 230 through the switch sw-a2. The switch sw-a2 opens and closes simultaneously with sw-a1. Therefore, the sensor unit 242 is also electrically connected to the sensor pixel 230 only at the time when the constant current supply unit 241 is connected to the sensor pixel 230. Although the specific connection relationship of the sensor unit 242 at this time is not illustrated separately, referring to FIG. 4, it can be seen that the sensor unit 242 is connected to the sensor pixel 230 in parallel. The sensor unit 242 is connected to the sensor pixel 230 only at the time of sensing in the end to measure the voltage applied to the sensor pixel 230.

The voltage storage unit 243 is electrically connected to the sensor unit 242. The voltage storage unit 242 is the same as the organic light emitting display device 100 according to the exemplary embodiment of the present invention except that the voltage value measured by the sensor unit 242 is stored only during the sensing time. Therefore, the following description is omitted.

The voltage corrector 244 is electrically connected to the voltage storage unit 243 and the power supply unit 220. The voltage corrector 244 is an organic electroluminescence according to an embodiment of the present invention except that the voltage value of the power supply unit 220 is corrected by the voltage value stored in the voltage storage unit 243 at the time of sensing. It is the same as the display apparatus 100. Therefore, the following description is omitted.

The organic light emitting display device 200 according to another exemplary embodiment of the present invention has the feature that the constant current supply unit 241 and the power supply unit 220 are electrically connected to the sensor pixel 230. Therefore, the sensing cycle can be set as desired. In addition, when the data value supplied to the sensor pixel 230 is supplied to the OFF state for more than an effective storage time, the sensing period is more freely by correcting the voltage value of the voltage storage unit through additional light emission that is not distinguished by the naked eye. Can be set.

As described above, the organic light emitting display device according to the present invention can correct the luminance change due to deterioration and temperature change of the organic light emitting diode OLED by using pixels used for actual screen display.

In addition, as described above, a time for sensing may be freely set for correction of a change in luminance of the organic light emitting diode OLED.

What has been described above is only one embodiment for implementing the organic light emitting display device according to the present invention, and the present invention is not limited to the above-described embodiment, and as claimed in the following claims, Without departing from the gist of the present invention, one of ordinary skill in the art will have the technical spirit of the present invention to the extent that various modifications can be made.

Claims (40)

An organic light emitting display panel including a data driver and a plurality of pixel circuits; A power supply electrically connected to the organic light emitting display panel; At least one sensor pixel selected from a pixel circuit of the organic light emitting display panel; And An organic light emitting display device comprising a control unit electrically connected to the sensor pixel. The control unit supplies a constant current to the sensor pixel and corrects the voltage of the power supply unit. The organic light emitting display device of claim 1, wherein the data driver of the organic light emitting display panel is electrically connected to the pixel circuits except for the sensor pixels. The organic light emitting display device of claim 1, wherein the power supply unit is electrically connected to the remaining pixel circuits except for the sensor pixel. The method of claim 1, wherein the control unit A constant current supply unit electrically connected to the sensor pixel to supply a current; A sensor unit electrically connected to the sensor pixel to measure a voltage formed in the sensor pixel; A voltage storage unit electrically connected to the sensor unit to store a voltage measured by the sensor unit; And And a voltage correction unit connected to the voltage storage unit and the power supply unit and correcting a voltage of the power supply unit. The organic light emitting display device of claim 4, wherein the constant current supply unit is further electrically connected to the data driver. The organic light emitting display device as claimed in claim 5, wherein the constant current supply unit supplies a current controlled by the data driver to the sensor pixel. The organic light emitting display device as claimed in claim 4, wherein the sensor unit measures a voltage formed in the organic light emitting element of the sensor pixel. The organic light emitting display device as claimed in claim 4, wherein the voltage storage unit is any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory. The organic light emitting display as claimed in claim 4, wherein the voltage corrector controls the supply voltage of the power supply unit to a voltage value stored in the voltage storage unit. An organic light emitting display panel including a data driver and a plurality of pixel circuits; A power supply electrically connected to the organic light emitting display panel; At least one sensor pixel selected from a pixel circuit of the organic light emitting display panel; And An organic light emitting display device comprising a control unit electrically connected to the sensor pixel. And the power supply unit and the control unit are complementarily connected to the sensor pixel, wherein the control unit supplies a constant current to the sensor pixel and corrects a voltage of the power supply unit. The organic light emitting display device of claim 10, wherein the data driver of the organic light emitting display panel is electrically connected to the pixel circuits other than the sensor pixel. The organic light emitting display device of claim 10, wherein the power supply unit is electrically connected to the pixel circuits other than the sensor pixel. The method of claim 10, wherein the control unit A constant current supply unit electrically connected to the sensor pixel to supply a current; A sensor unit electrically connected to the sensor pixel to measure a voltage formed in the sensor pixel; A voltage storage unit electrically connected to the sensor unit to store a voltage measured by the sensor unit; And And a voltage correction unit connected to the voltage storage unit and the power supply unit and correcting a voltage of the power supply unit. The organic light emitting display device of claim 13, wherein the constant current supply unit is further electrically connected to the data driver. The organic light emitting display device as claimed in claim 14, wherein the constant current supply unit supplies a current controlled by the data driver to the sensor pixel. The organic light emitting display as claimed in claim 14, wherein the constant current supply unit further emits the sensor pixel when the sensor pixel does not emit light for an effective storage time or longer. The organic light emitting display device as claimed in claim 16, wherein the time for additional light emission of the sensor pixel is equal to or less than sixteenths of one frame period. The organic light emitting display device of claim 13, wherein the sensor unit measures a voltage formed in the organic light emitting element of the sensor pixel. The organic light emitting display device of claim 13, wherein the voltage storage unit is one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory. The organic light emitting display as claimed in claim 13, wherein the voltage corrector controls the supply voltage of the power supply unit to a voltage value stored in the voltage storage unit. An organic electroluminescent display panel comprising an organic electroluminescent display panel including a data driver and a plurality of pixel circuits; A power supply step of supplying a voltage to the organic light emitting display panel by a power supply unit; A sensor pixel driving step in which the sensor pixel is driven by a constant current supplied by the controller; And a power supply voltage correcting step of the control unit correcting a voltage of the power supply unit. 22. The method of claim 21, wherein the data driver of the step of providing the organic light emitting display panel is electrically connected to the remaining pixel circuits except for the sensor pixel. 22. The method of claim 21, wherein the power supply unit of the power supply step is electrically connected to the pixel circuits other than the sensor pixel. The method of claim 21, wherein the control unit of the sensor pixel driving step A constant current supply unit electrically connected to the sensor pixel to supply a current; A sensor unit electrically connected to the sensor pixel to measure a voltage formed in the sensor pixel; A voltage storage unit electrically connected to the sensor unit to store a voltage measured by the sensor unit; And And a voltage correction unit connected to the voltage storage unit and the power supply unit and correcting a voltage of the power supply unit. 25. The method of claim 24, wherein the constant current supply unit of the sensor pixel driving step is further electrically connected to the data driver. 26. The method of claim 25, wherein the constant current supply unit of the sensor pixel driving step supplies a current controlled by the data driver to the sensor pixel. 25. The method of claim 24, wherein the sensor unit in the sensor pixel driving step measures a voltage formed in the organic electroluminescent element of the sensor pixel. 25. The method of claim 24, wherein the voltage storage unit of the sensor pixel driving step is any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory. 25. The method of claim 24, wherein the voltage correcting unit of the sensor pixel driving step controls the supply voltage of the power supply unit to a voltage value stored in the voltage storage unit. An organic electroluminescent display panel comprising an organic electroluminescent display panel including a data driver and a plurality of pixel circuits; A power supply step of supplying a voltage to the organic light emitting display panel by a power supply unit; A sensor pixel driving step in which the sensor pixel is driven by a constant current supplied by the controller; A power supply voltage correction step of correcting the voltage of the power supply unit by the control unit; And a control unit connected to the sensor pixel complementary to the power supply unit, wherein the control unit emits a sensor pixel to supply a constant current to the sensor pixel and correct the voltage of the power supply unit. A method of driving a light emitting display device. 31. The method of claim 30, wherein the data driver of the organic light emitting display panel is electrically connected to the remaining pixel circuits except for the sensor pixel in the providing of the organic light emitting display panel. 31. The method of claim 30, wherein the power supply unit of the power supply step is electrically connected to the pixel circuits other than the sensor pixel. The method of claim 30, wherein the control unit of the sensor pixel driving step A constant current supply unit electrically connected to the sensor pixel to supply a current; A sensor unit electrically connected to the sensor pixel to measure a voltage formed in the sensor pixel; A voltage storage unit electrically connected to the sensor unit to store a voltage measured by the sensor unit; And And a voltage correction unit connected to the voltage storage unit and the power supply unit and correcting a voltage of the power supply unit. 34. The method of claim 33, wherein the constant current supply unit of the sensor pixel driving step is further electrically connected to the data driver. 35. The method of claim 34, wherein the constant current supply unit of the sensor pixel driving step supplies the current to the sensor pixel controlled according to the data value of the data driver. 35. The method of claim 34, wherein the constant current supply unit of the sensor pixel driving step causes the sensor pixel to additionally emit light when the sensor pixel does not emit light for an effective storage time or more. . 37. The method of claim 36, wherein a time for additional light emission of the sensor pixel in the sensor pixel driving step is equal to or less than sixteenths of one frame period. 34. The method of claim 33, wherein the sensor unit in the sensor pixel driving step measures a voltage formed in the organic electroluminescent element of the sensor pixel. 34. The method of claim 33, wherein the voltage storage unit of the sensor pixel driving step is any one selected from a capacitive element, an EPROM, an EEPROM, and a flash memory. 34. The method of claim 33, wherein the voltage correcting unit of the sensor pixel driving step controls the supply voltage of the power supply unit to a voltage value stored in the voltage storage unit.

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