KR20090043294A - Organic light emitting display and driving method thereof - Google Patents

Abstract

The present invention provides a display device comprising: a display unit in which a first sub pixel and a second sub pixel which emit light in response to a first scan signal and a second scan signal supplied from a first scan line and a second scan line are arranged in a matrix form; A scan driver configured to supply a first scan signal and a second scan signal through first scan wires and second scan wires connected to the first sub pixel and the second sub pixel; And a signal supply driving for supplying a first data signal or a second data signal through a first data line and a second data line connected to the first sub pixel and the second sub pixel, and included in the first sub pixel and the second sub pixel. The present invention provides an organic light emitting display device including a data driver to alternate voltage sensing driving for sensing a voltage of a first electrode of a first organic light emitting diode or a second organic light emitting diode.

OLED display, voltage sensing, compensation

Description

Organic light emitting display and driving method thereof

The present invention relates to an organic light emitting display device and a driving method thereof.

An organic light emitting display device used in an organic light emitting display device is a self-light emitting device in which a light emitting layer is formed between two electrodes positioned on a substrate.

The organic light emitting device has a top emission type and a bottom emission type depending on the direction of light emission, and a passive matrix type and an active matrix type depending on the driving method. Matrix).

In the organic light emitting display device using an active matrix type of the organic light emitting display device, when a signal is supplied to a plurality of sub pixels arranged in a matrix form on the display unit, a transistor, a capacitor, and an organic light emitting diode positioned inside the sub pixel are driven. The image can be displayed.

However, organic light emitting diodes have a problem in that display quality deteriorates with time, such as deterioration of devices such as thin film transistors, capacitors, and organic light emitting diodes.

Therefore, there is a need to propose a method for solving such a problem in the conventional organic light emitting display device.

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic light emitting display device and a driving method thereof capable of selectively detecting a state of a subpixel and adjusting data to be supplied to the subpixel based on the detected value. To provide.

According to the above-described problem solving means, the present invention provides a matrix arrangement in which a first sub pixel and a second sub pixel which emit light in response to a first scan signal and a second scan signal supplied from a first scan line and a second scan line are arranged in a matrix form. Display unit; A scan driver configured to supply a first scan signal and a second scan signal through first scan wires and second scan wires connected to the first sub pixel and the second sub pixel; And a signal supply driving for supplying a first data signal or a second data signal through a first data line and a second data line connected to the first sub pixel and the second sub pixel, and included in the first sub pixel and the second sub pixel. The present invention provides an organic light emitting display device including a data driver to alternate voltage sensing driving for sensing a voltage of a first electrode of a first organic light emitting diode or a second organic light emitting diode.

As the first and second scan signals are alternately supplied from the scan driver, the first sub pixel and the second sub pixel may alternate the light emission operation and the detection operation.

The data driver may select a signal supply driving and a voltage sensing driving by a switch located inside or outside.

When the data driver performs a sensing drive, the voltage of the first electrode of the first organic light emitting diode is supplied through the second data wire, and the voltage of the first electrode of the second organic light emitting diode is supplied through the first data wire. I can receive it.

When the data driver performs a sensing drive, the voltage of the first electrode of the first organic light emitting diode is supplied through the second data wire, and the voltage of the first electrode of the second organic light emitting diode is adjacent to the third data wire. Can be supplied.

The data driver includes a lookup table in which data between a minimum value and a maximum value of a data signal supplied to a first subpixel or a second subpixel is data, and a reference for receiving a random value from an external source and generating a different reference voltage range. It may include a voltage generator.

The data driver compares the reference voltage with the voltage of the first electrode, selects data preset in the lookup table according to the difference between the reference voltage and the voltage of the first electrode, and selects the data in the first subpixel or the second subpixel based on the selected data. A data signal to be supplied can be generated.

The first subpixel includes a first switching transistor having a gate connected to the first scan line and one end connected to the first data line, and a first connected to a first end of the first power supply line and a gate connected to the other end of the first switching transistor. A first organic light emitting diode having a driving transistor, a first capacitor connected between one end and a gate of the first driving transistor, a first electrode connected to the other end of the first driving transistor, and a second electrode connected to the second power line; One end of the first organic light emitting diode may include a first monitor transistor having one end connected to a second data line connected to a second sub pixel and a gate connected to a first scan line.

The second subpixel may include a second switching transistor having a gate connected to the second scan line and one end connected to the second data line, and a second connected to a first end of the first power line and a gate connected to the other end of the second switching transistor. A second organic light emitting diode having a driving transistor, a second capacitor connected between one end and a gate of the second driving transistor, a first electrode connected to the other end of the second driving transistor, and a second electrode connected to the second power line; The second organic light emitting diode may include a second monitor transistor having one end connected to a first electrode of the second organic light emitting diode, the other end connected to a first data line connected to the first sub pixel, and a gate connected to the second scan line.

The second subpixel may include a second switching transistor having a gate connected to the second scan line and one end connected to the second data line, and a second connected to a first end of the first power line and a gate connected to the other end of the second switching transistor. A second organic light emitting diode having a driving transistor, a second capacitor connected between one end and a gate of the second driving transistor, a first electrode connected to the other end of the second driving transistor, and a second electrode connected to the second power line; The second organic light emitting diode may include a second monitor transistor having one end connected to a first electrode of the second organic light emitting diode, the other end connected to a third data line connected to a neighboring third sub pixel, and a gate connected to the second scan line.

On the other hand, in another aspect of the present invention, a first sub to supply a first scan signal to the first scan line to drive the first monitor transistor and to supply the first data signal to the first data line to emit light of the first sub pixel. Pixel emission step; A second sub-pixel emission step of supplying a second scan signal to the second scan line to drive the second monitor transistor and supplying a second data signal to the second data line to emit the second sub pixel; And detecting the first electrode of the first organic light emitting diode or the second organic light emitting diode included in the first sub pixel and the second sub pixel through the first data line and the second data line, and detecting the voltage of the first electrode. A method of driving an organic light emitting display device includes comparing a difference of a reference voltage and generating a data signal to be supplied to a first sub pixel or a second sub pixel.

When the first organic light emitting diode emits light, the compensating step senses the first electrode voltage of the second organic light emitting diode and when the second organic light emitting diode emits light, the compensating step first electrode voltage of the first organic light emitting diode Can be detected.

When the first organic light emitting diode emits light, in the compensating step, the first electrode voltage of the second organic light emitting diode is sensed, and when the second organic light emitting diode emits light, in the compensating step, the first of the neighboring third organic light emitting diodes is used. The electrode voltage can be detected.

The first sub-pixel and the second sub-pixel may alternate the light emission operation and the detection operation as the first scan signal and the second scan signal are alternately supplied.

The first scan signal and the second scan signal are supplied from the scan driver, and the scan driver detects the first sub pixel and the second sub pixel arranged in the first to nth scan lines, respectively, for each scan line. The pulses of the scan signal supplied to the scan line can be varied to perform.

The first scan signal and the second scan signal are supplied from the scan driver, and the scan driver includes n or more scan lines for the first sub pixel and the second sub pixel arranged in the first to nth scan lines, respectively. The pulse of the scan signal supplied to the scan line may be changed to define a block for each block and perform a sensing operation for each defined block.

In the compensating step, the voltage of the first electrode and the reference voltage are compared, and the data preset in the lookup table are selected according to the difference between the voltage and the reference voltage of the first electrode, and the first subpixel or the second subpixel is selected based on the selected data. A data signal to be supplied can be generated.

The present invention has an effect of providing an organic light emitting display device and a driving method thereof capable of selectively detecting a state of a subpixel and adjusting data to be supplied to the subpixel based on the detected value. Accordingly, there is an effect that can solve the problem that the display quality is degraded, such as the driving characteristics are changed by the influence that may occur in the elements included in the sub-pixel.

Hereinafter, with reference to the accompanying drawings, the specific content for the practice of the present invention will be described.

1 is a schematic plan view of an organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 1, in the organic light emitting display device, a display unit 130 including a plurality of subpixels 120 disposed in a matrix form on a substrate 110 may be located.

The subpixel 120 may include a red subpixel 120R, a green subpixel 120G, and a blue subpixel 120B, but add another color to emit light, such as a white subpixel or an orange subpixel. Can be further formed.

Accordingly, three or more subpixels 120 may be formed according to the purpose. In the present invention, three subpixels, that is, the red, green, and blue subpixels 120R, 120G, and 120B are located in a plurality of positions in a matrix form. One example will be described.

On the outer substrate 110 of the display unit 130, a plurality of wires 140 connected to the sub pixel 120 may be positioned. The plurality of wirings 140 may include a first power wiring and a second power wiring for supplying a voltage to the subpixel 120. In addition, the sub-pixel 120 may include a first wiring and a second wiring for supplying a scan signal and an activation signal. In addition, the sub-pixel 120 may include a data line for supplying a data signal. In addition, it may include a monitor wiring that can detect the state of the sub-pixel 120.

The driving unit 150 may be positioned on the outer lower substrate 110 of the display unit 130.

The driver 150 may include a scan driver connected to first and second wires, which are part of the plurality of wires 140, to supply a scan signal and an activation signal to the subpixels 120. In addition, the driver 150 may include a data driver connected to a data line, which is another part of the plurality of wires 140, to supply a data signal to the subpixels 120. In addition, the driver 150 may include a compensation driver connected to a monitor wire, which is another part of the plurality of wires 140, to detect a state of the subpixels 120. A detailed description of the compensation driver is added to the following.

Meanwhile, in the present invention, for convenience of description, the scan driver, the data driver, and the compensation driver are positioned as a single chip in the driver 150, but the scan driver and the data driver are separately designed and the compensation driver may be mounted in the data driver. It may be. Hereinafter, it is assumed that the data driver and the compensation driver are mounted on the same chip and interoperate with each other.

The pad unit 155 may be located on the outer substrate 110 of the driving unit 150.

The pad unit 155 is intended for electrical connection between the substrate 110 and the external circuit board 160, and the connection between the substrate 110 and the external circuit board 160 is a flexible cable (eg, FPC) ( 165) and the like, but is not limited thereto.

For reference, the driving unit 150 is disposed on the substrate 110 as described above, which is referred to as a chip on glass (COG) method. The driving unit 150 may further include a chip on film arranged on the flexible cable 165. ) Can be designed in such a way as to. That is, the connection with the substrate 110, the driver 150, and the external circuit board 160 may be flexibly designed according to the design method.

On the other hand, on the external circuit board 160, a power supply unit 170 connected to the first power line and the second power line, which is a part of the plurality of wires 140, to supply the voltage to the subpixel 120 may be located. have. In addition, a timing controller 180 may be provided on the external circuit board 160 to supply a scan signal, an activation signal, a data signal, etc. to the driver 150, and other driving devices may be further located.

Hereinafter, the cross-sectional structure of one subpixel will be attached and described in more detail. However, the structure of the subpixel is merely exemplary and is not limited thereto.

2A and 2B are cross-sectional views illustrating subpixels according to an exemplary embodiment of the present invention.

First, referring to FIG. 2A, the substrate 110 may be located.

The substrate 110 may be selected as a material for forming an element having excellent mechanical strength or dimensional stability. As the material of the substrate 110, a glass plate, a metal plate, a ceramic plate or a plastic plate (polycarbonate resin, acrylic resin, vinyl chloride resin, polyethylene terephthalate resin, polyimide resin, polyester resin, epoxy resin, silicone resin, fluorine) Resin, etc.) is mentioned.

The buffer layer 111 may be positioned on the substrate 110. The buffer layer 111 may be formed to protect the thin film transistor formed in a subsequent process from impurities such as alkali ions flowing out of the substrate 110. The buffer layer 111 may use silicon oxide (SiO ₂ ), silicon nitride (SiNx), or the like.

The semiconductor layer 112 may be positioned on the buffer layer 111. The semiconductor layer 112 may include amorphous silicon or polycrystalline silicon obtained by crystallizing the same. Although not shown here, the semiconductor layer 112 may include a channel region, a source region, and a drain region, and the source region and the drain region may be doped with P-type or N-type impurities.

The gate insulating layer 113 may be positioned on the substrate 110 including the semiconductor layer 112. The gate insulating layer 113 may be selectively formed using silicon oxide (SiO ₂ ), silicon nitride (SiNx), or the like.

The gate electrode 114 may be positioned on the gate insulating layer 113 to correspond to the channel region of the semiconductor layer 112. The gate electrode 114 is made of aluminum (Al), aluminum alloy (Al alloy), titanium (Ti), silver (Ag), molybdenum (Mo), molybdenum alloy (Mo alloy), tungsten (W), tungsten silicide (WSi _2). It may include any one of).

An interlayer insulating film 115 may be positioned on the substrate 110 including the gate electrode 114. The interlayer insulating film 115 may be an organic film or an inorganic film, or may be a composite film thereof.

When the interlayer insulating film 115 is an inorganic film, the interlayer insulating film 115 may include silicon oxide (SiO ₂ ), silicon nitride (SiNx), or SOG (silicate on glass). On the other hand, the organic film may include an acrylic resin, a polyimide resin or a benzocyclobutene (BCB) resin. First and second contact holes 115a and 115b may be disposed in the interlayer insulating layer 115 and the gate insulating layer 113 to expose a portion of the semiconductor layer 112.

The first electrode 116a may be positioned on the interlayer insulating film 115. The first electrode 116a may be a first electrode and may have a single layer structure including a conductive layer such as indium tin oxide (ITO) or indium zinc oxide (IZO). In addition, the first electrode 116a may have a multilayer structure including a conductive layer such as indium tin oxide (ITO) or indium zinc oxide (IZO). The description thereof will be described in more detail with reference to the accompanying drawings.

Source and drain electrodes 116b and 116c may be positioned on the interlayer insulating film 115. The source electrode and the drain electrode 116b and 116c may be electrically connected to the semiconductor layer 112 through the first and second contact holes 115a and 115b. A portion of the drain electrode 116c may be positioned on the first electrode 116a and electrically connected to the first electrode 116a.

The source and drain electrodes 116b and 116c may include a low resistance material to lower the wiring resistance. Here, the source electrode and the drain electrode 116b and 116c may be formed of aluminum (Al), aluminum (Alnd), molybdenum (Mo), chromium (Cr), titanium nitride (TiN), molybdenum nitride (MoN), or chromium. It may be formed into a multilayer structure including a metal layer such as nitride (CrN). The description thereof will be described in more detail with reference to the accompanying drawings.

The transistor located on the ideal substrate 110 may include a gate electrode 114, a source electrode, and a drain electrode 116b and 116c, and a transistor array having a plurality of transistors and capacitors may be electrically connected to the following organic light emitting diodes. have. (However, the structure of the capacitor is omitted)

An insulating layer 117 exposing a portion of the first electrode 116a may be disposed on the first electrode 116a (eg, the first electrode). The insulating layer 117 may include an organic material such as benzocyclobutene (BCB) resin, acrylic resin, or polyimide resin.

The organic light emitting layer 118 may be disposed on the exposed first electrode 116a, and the second electrode 119 (eg, the second electrode) may be positioned on the organic light emitting layer 118. The second electrode 119 may be a second electrode supplying electrons to the organic light emitting layer 118, and may include magnesium (Mg), silver (Ag), calcium (Ca), aluminum (Al), or an alloy thereof. Can be.

The organic light emitting diode connected to the source or drain electrodes 116b and 116c of the transistor included in the transistor array on the ideal substrate 110 includes the first electrode 116a, the organic light emitting layer 118, and the second electrode 119. It may include.

Unlike FIG. 2A, referring to FIG. 2B, the first electrode 116a positioned on the source or drain electrodes 116b and 116c may be positioned on the planarization layer 117a to planarize the surface of the transistor array. In this case, the insulating layer 117b may be positioned on the planarization layer 117a to expose a portion of the first electrode 116a (eg, the first electrode).

Meanwhile, in the sub pixel structures shown in FIGS. 2A and 2B, the structure of the transistor included in the transistor array may vary depending on whether the gate structure is a top gate or a batam gate. In addition, the structure of the transistor may vary depending on the number of masks used in forming the transistor array and the semiconductor layer material. Therefore, the structure of the subpixel is not limited thereto as described above.

On the other hand, in the organic light emitting display device as described above, the first sub-pixel and the second sub-pixel which emit light in response to the first scan signal and the second scan signal supplied from the first scan wiring and the second scan wiring are matrix-shaped. It may include a display unit arranged as. The scan driver may include a scan driver configured to supply the first scan signal and the second scan signal through first scan wires and second scan wires connected to the first sub pixel and the second sub pixel. In addition, the signal supply driving for supplying the first data signal or the second data signal through the first data line and the second data line connected to the first sub pixel and the second sub pixel, and to the first sub pixel and the second sub pixel. The first organic light emitting diode or the second organic light emitting diode may include a data driver to alternate the voltage sensing driving for sensing the voltage of the first electrode.

That is, when the plurality of subpixels emit light due to the above configuration, the organic light emitting display device according to an embodiment of the present invention senses the voltage supplied to one selected from among the plurality of subpixels and selects the selected voltage based on the detected voltage. It has a subpixel circuit configuration that can generate and compensate a data signal to be supplied to the subpixel.

Hereinafter, a circuit configuration of the subpixel will be described in more detail, but one or more subpixels are illustrated and described for clarity and understanding of the description.

3 is a diagram illustrating a circuit configuration of a subpixel according to an exemplary embodiment of the present invention, and FIG. 4 is a diagram illustrating a circuit configuration of a subpixel according to another exemplary embodiment of the present invention.

Referring to FIG. 3, a connection relationship between sub pixels 1 and sub pixel 2 may be as follows.

First, the first subpixel subpixel1 may include a first switching transistor S1 having a gate connected to the first scan line Scan1 and one end connected to the first data line Data1. In addition, a gate may be connected to the other end of the first switching transistor S1 and may include a first driving transistor T1 having one end connected to the first power line Vdd. In addition, the first capacitor C1 may include a first capacitor C1 connected between one end of the first driving transistor T1 and the gate. In addition, the first organic light emitting diode D1 may include a first electrode connected to the other end of the first driving transistor T1 and a second electrode connected to the second power line Gnd. In addition, one end is connected to the first electrode of the first organic light emitting diode D1 and the other end is connected to the second data line Data2 connected to the second sub pixel2, and the gate is connected to the first scan line Scan1. May include a first monitor transistor M1 connected thereto.

Next, the second sub pixel2 may include a second switching transistor S2 having a gate connected to the second scan line Scan2 and one end connected to the second data line Data2. In addition, the second driving transistor T2 may include a second driving transistor T2 having a gate connected to the other end of the second switching transistor S2 and having one end connected to the first power line Vdd. In addition, a second capacitor C2 connected between one end of the second driving transistor T2 and the gate may be included. The second organic light emitting diode D2 may include a second organic light emitting diode D2 connected to the other end of the second driving transistor T2 and connected to the second power line Gnd. In addition, one end is connected to the first electrode of the second organic light emitting diode D2 and the other end is connected to the first data line Data1 connected to the first sub pixel1, and the gate is connected to the second scan line Scan2. May include a second monitor transistor M2 connected thereto.

When the first and second scan signals are supplied from the scan driver, the first and second sub-pixels sub pixel1 and sub pixel2 arranged in the display unit have the above-mentioned connection relationship. The transistors S1 and S2 can be driven. When the first and second data signals are supplied from the data driver, data voltages corresponding to the first and second data signals may be stored in the first and second capacitors C1 and C2. The first and second driving transistors T1 and T2 may be driven by data voltages stored in the first and second capacitors C1 and C2. When the first and second driving transistors T1 and T2 are driven, the first and second organic light emitting diodes D1 and D2 may emit light.

In this case, when the first scan signal is supplied, the first monitor transistor M1 is driven, and the data driver is connected to the second sub-pixel subpixel2 through the second data line Data2. The voltage of the first electrode of the first organic light emitting diode included in the pixel sub pixel1 may be sensed.

In this case, when the second scan signal is supplied, the second monitor transistor M2 is driven, and the data driver is connected to the first sub-pixel subpixel1 through the first data line Data1. The voltage of the first electrode of the second organic light emitting diode included in the pixel subpixel2 may be sensed.

In the above connection relationship, when the first scan signal and the second scan signal are alternately supplied from the scan driver, the first subpixel subpixel1 and the second subpixel2 alternate light emission operation and detection operation. can do. In this case, the data driver may sense the voltage of the first electrode of the organic light emitting diode of the subpixel performing the sensing operation. However, when the first subpixel subpixel1 emits light, the second subpixel2 performs a sensing operation of detecting the first subpixel1, and the second subpixel2 subpixel2 In the case of emitting light, the first sub-pixel subpixel1 performs a sensing operation of sensing the second sub-pixel2.

As a result, the sub-pixels positioned in the display unit alternately perform the light emission operation and the detection operation in pairs of two sub pixels as shown in Table 1 below.

Subsequently, the data driver may generate a data signal to be supplied to the corresponding subpixel based on the sensed voltage of the first electrode of the subpixel and supply a compensation signal in the next scan period. It demonstrates below.

In contrast, referring to FIG. 4, the connection relationship between the subpixels sub pixel1, sub pixel2, and sub pixel3 may be as follows.

First, the first subpixel subpixel1 may include a first switching transistor S1 having a gate connected to the first scan line Scan1 and one end connected to the first data line Data1. In addition, a gate may be connected to the other end of the first switching transistor S1 and may include a first driving transistor T1 having one end connected to the first power line Vdd. In addition, the first capacitor C1 may include a first capacitor C1 connected between one end of the first driving transistor T1 and the gate. In addition, the first organic light emitting diode D1 may include a first electrode connected to the other end of the first driving transistor T1 and a second electrode connected to the second power line Gnd. In addition, one end is connected to the first electrode of the first organic light emitting diode D1 and the other end is connected to the second data line Data2 connected to the second sub pixel2, and the gate is connected to the first scan line Scan1. May include a first monitor transistor M1 connected thereto.

Next, the second sub pixel2 may include a second switching transistor S2 having a gate connected to the second scan line Scan2 and one end connected to the second data line Data2. In addition, the second driving transistor T2 may include a second driving transistor T2 having a gate connected to the other end of the second switching transistor S2 and having one end connected to the first power line Vdd. In addition, a second capacitor C2 connected between one end of the second driving transistor T2 and the gate may be included. The second organic light emitting diode D2 may include a second organic light emitting diode D2 connected to the other end of the second driving transistor T2 and connected to the second power line Gnd. In addition, one end is connected to the first electrode of the second organic light emitting diode D2 and the other end is connected to the third data line Data3 connected to the neighboring third sub pixel, and the second scan line Scan2. It may include a second monitor transistor (M2) connected to the gate.

Next, the third subpixel subpixel3 may have the same basic circuit configuration and connection relationship with the first subpixel1 and the second subpixel subpixel. However, one end of the third monitor transistor M3 is connected to a first electrode of the third organic light emitting diode D3 and the other end is connected to a fourth data line (not shown) connected to a neighboring fourth subpixel (not shown). The gate may be connected to the first scan line Scan1.

The first sub-pixel 1, the second sub-pixel 2 and the third sub-pixel 3, which are arranged on the display unit to have the above connection relationship, have the first scan signal and the second scan signal from the scan driver. When supplied, the first, second and third switching transistors S1, S2, and S3 may be driven. When the first, second, and third data signals are supplied from the data driver, the first, second, and third capacitors C1, C2, and C3 may have data voltages corresponding to the first, second, and third data signals. Can be saved. The first, second, and third driving transistors T1, T2, and T3 may be driven by data voltages stored in the first, second, and third capacitors C1, C2, and C3. When the first, second, and third driving transistors T1, T2, and T3 are driven, the first, second, and third organic light emitting diodes D1, D2, and D3 may emit light.

In this case, when the first scan signal is supplied, the first and third monitor transistors M1 and M3 are driven, and the data driver is connected to the second data line Data2 connected to the second subpixel2. The voltage of the first electrode of the first organic light emitting diode D1 included in the first sub pixel1 may be sensed. In addition, the data driver includes a voltage of the first electrode of the third organic light emitting diode D3 included in the third subpixel3 through a fourth data line connected to the fourth subpixel (not shown). Can be detected.

Here, when the second scan signal is supplied, the second monitor transistor M2 is driven, and the data driver is connected to the second subpixel through a third data line Data3 connected to the second subpixel1. The voltage of the first electrode of the second organic light emitting diode D2 included in the sub pixel2 may be sensed.

When the first scan signal and the second scan signal are alternately supplied from the scan driver, the first subpixel subpixel1, the third subpixel3 subpixel2, and the second subpixel2 subpixel2 are connected to each other. ) And the light emission operation and the detection operation can be alternated. In this case, the data driver may sense the voltage of the first electrode of the organic light emitting diode of the subpixel performing the sensing operation. However, when the first subpixel subpixel1 emits light, the second subpixel2 performs a sensing operation of detecting the first subpixel1, and the second subpixel2 subpixel2 When the light emitting operation is performed, the third sub pixel 1 performs a sensing operation of sensing the second sub pixel 2.

Thus, when the first subpixel performs the light emitting operation, the neighboring second subpixel performs the sensing operation of sensing the first subpixel, and when the second subpixel performs the light emitting operation, the neighboring third subpixel. The subpixel performs a sensing operation of sensing the second subpixel.

Subsequently, the data driver may generate a data signal to be supplied to the corresponding subpixel based on the sensed voltage of the first electrode of the subpixel and supply a compensation signal in the next scan period. It demonstrates below.

Hereinafter, a data driver for generating a data signal to be supplied to the subpixel based on the voltage of the first electrode transferred through the data line will be described in more detail.

5 is a schematic diagram of a data driver according to an exemplary embodiment of the present invention.

The data driver may select a signal supply driving and a voltage sensing driving by a switch SW located inside or outside. The switch SW may serve to select an output for driving a signal supply and an input for driving a voltage sensing drive through one data line Data. To this end, the switch SW may receive a control signal from a data driver.

On the other hand, the data driver includes a source unit (S-Driver) for outputting a data signal when driving a signal supply and a monitor unit (M-) for receiving the voltage of the first electrode of the organic light emitting diode included in the subpixel sensed during the voltage sensing driving. Driver) may be included. When the data driver drives the signal supply, the data signal generated from the source unit S-Driver may be output through the output terminal Dout, and the voltage of the first electrode detected from the subpixel during the voltage sensing drive is The monitor may be input to the monitor unit M-Driver through the input terminal Din.

Here, the monitor unit M-Driver is a lookup table in which the value between the minimum value and the maximum value of the data signal supplied to the sub-pixel is converted into data, and the external value (for example, a user, a microcomputer, etc.) of the arbitrary value USR. It may include a reference voltage generating unit for receiving from the input to generate a range of different reference voltage. Here, of course, the concept of data can be extended to other values such as registers and instructions.

The monitor M-driver may compare the reference voltage with the voltage of the first electrode and select data preset in the lookup table according to the difference between the reference voltage and the voltage of the first electrode.

Thereafter, the monitor unit M-Driver may transfer the selected data value FB to the source unit S-Driver. The source unit S-Driver, which receives the data value FB from the monitor unit M-Driver, generates a data signal to be supplied to the subpixel based on the data value FB, and converts the generated data signal into a data line Data. Can be supplied to the subpixel.

Accordingly, the monitor unit M-Driver may generate the data value FB to adjust the amount of the data signal or the voltage of the data signal output from the source unit S-Driver. The source unit S-Driver may adjust a data signal to be supplied to the subpixel based on the data value FB.

To help understand the description, the following assumptions are added.

It is assumed that the value obtained by data-forming the voltage flowing through the organic light emitting diode has a range of 1 to 100. At this time, any value that can be set by the reference voltage generator may be advantageously in the range of 1 to 100, but is not limited thereto.

Here, the range of the data value of the voltage flowing through the organic light emitting diode corresponds to the total grayscale data signal to be expressed in the subpixel, and the voltage corresponding to all the grayscale data signals is a range value flowing through the organic light emitting diode. Can be defined.

In addition to the above assumptions, assuming that an arbitrary value input from the outside has a value of 50, and at any point in time, assuming that the voltage of the first electrode sensed through a specific sub-pixel also has 50, the two values are the same. The data signal to be supplied to a specific sub pixel may not be adjusted. On the contrary, assuming that an arbitrary value input from the outside has 60, and at some point, assuming that the voltage of the first electrode sensed through a specific sub-pixel also has 50, the two values are different. Data may be generated to adjust a data signal to be supplied to a specific subpixel.

Therefore, the random value USR set in the reference voltage generator is a determination condition for detecting whether a value less than the original signal is supplied to a specific sub pixel when the data signal is supplied to the sub pixel. will be.

Therefore, the monitor unit (M-Driver) can determine whether or not to adjust the data signal to be supplied to a specific sub-pixel and how much to adjust the data signal in the next scan period based on the information obtained through such a process. Here, the larger the range of the data valued value is, the wider the range of the determination condition becomes, so that the data signal to be supplied to the subpixel can be more accurately adjusted.

Hereinafter, the driving method will be described. However, the circuit configuration of FIG. 3 is referred to for better understanding of the description.

First, in the first sub-pixel emission step, the first scan signal is supplied to the first scan line Scan1 to activate the first monitor transistor M1 and the first data signal is supplied to the first data line Data1. The subpixel 1 is emitted.

Next, in the second sub-pixel emission step, a second scan signal is supplied to the second scan line Scan2 to activate the second monitor transistor M2, and a second data signal is supplied to the second data line Data2. The sub-pixel 2 is emitted.

Next, the compensation step includes a first organic light emitting diode D1 included in the first subpixel1 and the second subpixel2 through the first data line Data1 and the second data line Data2. Alternatively, the first electrode of the second organic light emitting diode D2 may be sensed, and the difference between the detected voltage of the first electrode and the reference voltage may be compared and supplied to the first subpixel1 or the second subpixel2. Generating a data signal.

In the compensating step, the detected voltage of the first electrode of the organic light emitting diode is compared with the reference voltage, and the preset data are selected in the lookup table according to the difference between the voltage and the reference voltage of the first electrode and based on the selected data, the first subpixel. A data signal to be supplied to the sub pixel 1 or the second sub pixel 2 may be generated.

Meanwhile, when the first organic light emitting diode D1 emits light in the circuit configuration according to the embodiment of the present invention, in the compensating step, the first electrode voltage of the second organic light emitting diode D2 is sensed, and the second organic light emitting diode is emitted. When the diode D2 emits light, the first electrode voltage of the first organic light emitting diode D1 may be sensed in the compensating step (see circuit configuration of FIG. 3).

On the other hand, when the first organic light emitting diode D1 emits light in a circuit configuration according to another embodiment of the present invention, in the compensating step, the first electrode voltage of the second organic light emitting diode D2 is sensed and the second organic light emitting diode is emitted. When the diode D2 emits light, the first electrode voltage of the neighboring third organic light emitting diode D3 may be sensed in the compensating step (see the circuit configuration of FIG. 4).

In the above driving method, the first sub-pixel subpixel1 and the second sub-pixel subpixel1 may alternate light emitting and sensing operations as the first scan signal and the second scan signal are alternately supplied. .

Here, the first scan signal and the second scan signal may be supplied from the scan driver. The sensing operation may be variously performed according to a scan pulse output from the scan driver and a switch located inside or outside the data driver.

First, in order to perform a sensing operation for each scan line, a scan supplied to the scan lines of the first and second sub pixels sub pixel1 and sub pixel2 arranged in the first to nth scan lines, respectively. The pulse of the signal can be different.

In this case, the switch located inside or outside the data driver may change the switching operation to perform a sensing operation for each scan line.

Next, in order to define a subpixel block for each of n or more scan lines and perform a sensing operation for each of the defined blocks, the first subpixel (sub pixel1) and the first subpixel arranged in the nth scan line from the first scan line, respectively. Pulses of the scan signals supplied to the scan lines of the subpixels 2 may be different.

The present invention has an effect of providing an organic light emitting display device and a driving method thereof capable of selectively detecting a state of a subpixel and adjusting data to be supplied to the subpixel based on the detected value. Accordingly, there is an effect that can solve the problem that the display quality is degraded, such as the driving characteristics are changed by the influence that may occur in the elements included in the sub-pixel.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical configuration of the present invention described above may be modified in other specific forms by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features. It will be appreciated that it may be practiced. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is represented by the claims to be described later rather than the detailed description. Also, it is to be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

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

2A and 2B illustrate cross-sectional views of subpixels according to an exemplary embodiment of the present invention.

3 is an exemplary circuit configuration of a subpixel according to an embodiment of the present invention.

4 is an exemplary circuit configuration of a subpixel according to another exemplary embodiment of the present invention.

5 is a schematic diagram of a data driver in one embodiment of the present invention;

<Explanation of symbols on main parts of the drawings>

110: substrate 120: subpixel

130: display unit 140: a plurality of wirings

150: drive unit 160: external circuit board

170: power supply unit 180: timing controller unit

Claims (17)

A display unit in which a first sub pixel and a second sub pixel which emit light in response to the first scan signal and the second scan signal supplied from the first scan line and the second scan line are arranged in a matrix; A scan driver configured to supply a first scan signal and a second scan signal through the first scan wire and the second scan wire connected to the first sub pixel and the second sub pixel; And A signal supply driving for supplying a first data signal or a second data signal through a first data line and a second data line connected to the first sub pixel and the second sub pixel, and the first sub pixel and the second sub pixel. An organic light emitting display device comprising a data driver to alternate voltage sensing driving for sensing a voltage of a first organic light emitting diode or a second organic light emitting diode included in a pixel. The method of claim 1, The first sub pixel and the second sub pixel, And the light emitting operation and the sensing operation are alternately supplied as the first scan signal and the second scan signal are alternately supplied from the scan driver. The method of claim 1, The data driver, An organic light emitting display device which selects the signal supply driving and the voltage sensing driving by a switch located inside or outside. The method of claim 1, When the data driver performs a sensing drive, The organic light emitting display device in which the voltage of the first electrode of the first organic light emitting diode is supplied through the second data line, and the voltage of the first electrode of the second organic light emitting diode is supplied through the first data line. . The method of claim 1, When the data driver performs a sensing drive, The organic light emitting display, in which a voltage of a first electrode of the first organic light emitting diode is supplied through the second data line, and a voltage of a first electrode of the second organic light emitting diode is supplied through a neighboring third data line. Device. The method of claim 1, The data driver, A lookup table in which a value between a minimum value and a maximum value of a data signal supplied to the first subpixel or the second subpixel is converted into data; An organic light emitting display device comprising a generator. The method of claim 6, The data driver, Compare the reference voltage with the voltage of the first electrode, select data preset in the lookup table according to the difference between the reference voltage and the voltage of the first electrode, and select the first subpixel or the second based on the selected data. An organic light emitting display device for generating a data signal to be supplied to a sub pixel. The method of claim 1, The first sub pixel is, A first switching transistor having a gate connected to the first scan line and having one end connected to the first data line, a first driving transistor having a gate connected to the other end of the first switching transistor and one end connected to the first power line; A first organic light emitting diode having a first capacitor connected between one end of the first driving transistor and a gate, a first electrode connected to the other end of the first driving transistor, and a second electrode connected to a second power line; An organic light emitting display comprising a first monitor transistor having one end connected to a first electrode of a first organic light emitting diode, the other end connected to a second data line connected to the second sub pixel, and a gate connected to the first scan line. Device. The method of claim 8, The second sub pixel is, A second switching transistor having a gate connected to the second scan line and having one end connected to the second data line, a second driving transistor having a gate connected to the other end of the second switching transistor and one end connected to the first power line; A second organic light emitting diode connected between one end of the second driving transistor and a gate, a second organic light emitting diode having a first electrode connected to the other end of the second driving transistor, and a second electrode connected to a second power line; An organic light emitting display comprising a second monitor transistor having one end connected to a first electrode of a second organic light emitting diode, the other end connected to a first data line connected to the first subpixel, and a gate connected to the second scan line. Device. The method of claim 8, The second sub pixel is, A second switching transistor having a gate connected to the second scan line and having one end connected to the second data line, a second driving transistor having a gate connected to the other end of the second switching transistor and one end connected to the first power line; A second organic light emitting diode connected between one end of the second driving transistor and a gate, a second organic light emitting diode having a first electrode connected to the other end of the second driving transistor, and a second electrode connected to a second power line; An organic light emitting display device comprising a second monitor transistor having one end connected to a first electrode of a second organic light emitting diode, another end connected to a third data line connected to a third subpixel, and a gate connected to the second scan line. . A first sub-pixel emission step of supplying a first scan signal to the first scan line to drive the first monitor transistor and supplying a first data signal to the first data line to emit light of the first sub pixel; A second sub-pixel emission step of supplying a second scan signal to the second scan line to drive the second monitor transistor and supplying a second data signal to the second data line to emit the second sub pixel; And Sensing the first electrode of the first organic light emitting diode or the second organic light emitting diode included in the first sub pixel and the second sub pixel through the first data line and the second data line; Comparing the difference between the voltage of the electrode and the reference voltage and generating a data signal to be supplied to the first sub-pixel or the second sub-pixel driving method of an organic light emitting display device. The method of claim 11, When the first organic light emitting diode emits light, In the compensating step, the first electrode voltage of the second organic light emitting diode is sensed. When the second organic light emitting diode emits light, And in the compensating step, sensing the first electrode voltage of the first organic light emitting diode. The method of claim 11, When the first organic light emitting diode emits light, In the compensating step, the first electrode voltage of the second organic light emitting diode is sensed. When the second organic light emitting diode emits light, And in the compensating step, sensing the first electrode voltage of a neighboring third organic light emitting diode. The method of claim 11, The first sub pixel and the second sub pixel, And a light emitting operation and a sensing operation alternately supplied as the first scan signal and the second scan signal are alternately supplied. The method of claim 11, The first scan signal and the second scan signal are supplied from a scan driver, The scan driver, An organic light emitting diode emitting a pulse of a scan signal supplied to a scan line so that the first subpixel and the second subpixel arranged in the first to nth scan lines respectively perform a sensing operation for each scan line Method of driving display device. The method of claim 11, The first scan signal and the second scan signal are supplied from a scan driver, The scan driver, The first subpixel and the second subpixel arranged from the first scan line to the nth scan line, respectively, are defined in blocks for n or more scan lines and supplied to the scan lines to perform a sensing operation for each defined block. A method of driving an organic light emitting display device which varies pulses of a scan signal. The method of claim 11, In the compensation step, Compare the voltage of the first electrode and the reference voltage, select data preset in a look-up table according to the difference between the voltage of the first electrode and the reference voltage, and based on the selected data, the first sub-pixel or the second sub-sub. A method of driving an organic light emitting display device for generating a data signal to be supplied to a pixel.

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