KR101351422B1 - Organic Light Emitting Diode Display device and Driving method Thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting diode display and a method of driving the same, which reduce the drive current peak value of an organic EL element and reduce the current density without using a drive transistor. An organic EL element formed at an intersection region, a data line connected to a source terminal, a gate line connected to a gate terminal, an anode connected to a drain terminal of the first transistor, and a cathode connected to an electrode of a potential potential; and The potential of the emission control line is induced during the on-state period of the pixel circuit having a capacitor for charge accumulation having one end connected to the connection point of the drain terminal and the anode, and the emission control line connected to the other end of the capacitor and the first transistor. While maintaining the low potential at which no current flows in the EL element, the first transistor is turned off. Characterized in that it comprises a light emission control section that increases to a predetermined electric potential across the first vertical scanning period, the potential of the emission control line after the state.

Description

Organic Light Emitting Diode Display device and Driving method Thereof}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting diode (OLED) display device configured by arranging pixel circuits using organic EL (OEL: organic electro luminescence) elements and a driving method thereof.

In a conventional organic light emitting diode display device, a plurality of pixel circuits formed in each intersection region of a plurality of gate lines, a plurality of data lines, and a power supply line are respectively selected transistors (selective thin film transistors), capacitors, and driving devices. A transistor (drive TFT) and an organic EL element are provided.

In such an organic light emitting diode display, first, when a gate line is selected, the selection transistor is turned ON, and the data potential, which is a video signal from the data line, is stored as a charge in the capacitor. Then, the driving transistor is turned on in accordance with the charge accumulated in the capacitor, and the potential from the power supply line is applied to the organic EL element.

Here, the Vg-Id characteristic (relationship between gate potential Vg and drain current Id) of a general drive transistor is shown in FIG. In FIG. 8, the horizontal axis represents the gate potential, and the vertical axis represents the drain current. Further, the thick line portion indicates the drive current range (vertical axis direction) of the organic EL element, that is, the data potential range (horizontal axis direction) which is a video signal.

On the other hand, the luminous efficiency of the organic EL element which is an OLED material is improved year by year to emit the organic EL element with a small current. Specifically, in recent years, the drive current near the gradation has dropped to 10 kΩ or less. Therefore, there is a problem that the drive current range of the organic EL element is narrowed and it is difficult to secure a data potential range sufficient to carry out current control. In addition, irregularities in threshold voltage potentials occur in the driving transistor, so that the current control becomes more difficult when the driving current range of the organic EL element is narrowed.

Moreover, the relationship between the luminous efficiency of a general organic electroluminescent element, the power consumption of an organic electroluminescent element, and the ratio which the power consumed by a TFT board | substrate occupies for total power consumption is shown in FIG. In Fig. 9, the horizontal axis represents the luminous efficiency of the organic EL element, the left side of the vertical axis represents the power consumption of the organic EL element, and the right side of the vertical axis represents the ratio of power consumption to the total power consumption of the TFT substrate.

In Fig. 9, the power consumption of the organic EL element is lowered as the luminous efficiency of the organic EL element is improved, but it can be seen that the ratio of the power consumption to the TFT substrate to the total power consumption is increasing. That is, although the power consumption of organic electroluminescent element is falling, there existed a problem that the power consumption to a TFT substrate is increasing.

This is because the gate potential Vgs (source potential reference) near one gradation is largely secured, and the electric current control of the organic EL element is facilitated by increasing the potential difference of the data potential as the video signal. This is because the on-resistance is increased by suppressing the driving capability of the driving transistor low from the viewpoint of reducing the luminance gap of the organic EL element. In other words, it can be seen that the characteristics of the driving transistor are affected by the above problem.

Thus, an organic light emitting diode display in which the driving transistor is removed from the pixel circuit has been proposed (see Patent Document 1, for example). In the organic light emitting diode display, the plurality of pixel circuits formed in the intersection regions of the plurality of gate lines, the plurality of data lines, and the power supply line are each composed of a 1Tr 1C type having a selection transistor, a capacitor, and an organic EL element. have.

In such an organic light emitting diode display, first, by selecting a gate line, the selection transistor is turned on so that a data potential, which is a video signal from the data line, is applied to the organic EL element and accumulated in the capacitor as charge. Subsequently, when the gate line is in the non-selected state, the charge accumulated in the capacitor is supplied to the organic EL element.

Patent Document 1: Japanese Patent Application Laid-Open No. 8-54836

However, the prior art has the following problems.

In the organic light emitting diode display device described in Patent Document 1, when the selection transistor is in an on state, a data potential is applied to the organic EL element so that a current flows in the organic EL element in a short time.

Therefore, the peak value of the drive current of the organic EL element increases, and the current density increases, resulting in large damage to the organic EL film. As a result, there is a problem that the deterioration of the organic EL element is accelerated and the life is shortened.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an organic light emitting diode display and a method of driving the same, which can reduce the current density and reduce the current density of an organic EL element without using a driving transistor. The purpose is to provide.

The organic light emitting diode display according to the present invention for achieving the above object is formed in the intersection region of the data line and the gate line, the first transistor, the data line is connected to the source terminal, the gate line is connected to the gate terminal, A pixel circuit having an organic EL element in which an anode is connected to a drain terminal of one transistor, and a cathode is connected to an electrode of the potential of the electrostatic potential, and a capacitor for charge accumulation, one end of which is connected to a connection point of the drain terminal and the anode, During the on-state period of the connected emission control line and the first transistor, the potential of the emission control line is maintained at a low potential at which no current flows in the organic EL element, and the emission control is performed after the first transistor is turned off. A light emission controller for raising the potential of the line to a predetermined potential over one vertical scanning period Characterized in that.

In addition, the organic light emitting diode display according to the present invention is formed in the cross region of the data line and the gate line, the data line is connected to the source terminal, and the gate line is connected to the drain terminal of the first transistor and the first transistor. An emission control connected to a cathode of an organic EL element and a pixel circuit having an organic EL element connected with an anode, and a capacitor for charge accumulation having one end connected to a drain terminal and an anode connection point and the other end connected to an electrode of a potential potential During the on state period of the line and the first transistor, the potential of the emission control line is maintained at a value higher than the initial anode potential, and the potential of the emission control line is set to one vertical scanning period after the first transistor is turned off. It is characterized by including a light emission control part which lowers to predetermined electric potential over.

In addition, a method of driving an organic light emitting diode display according to the present invention includes a first transistor and a first transistor formed at an intersection region of a data line and a gate line, a data line connected to a source terminal, and a gate line connected to a gate terminal. An organic light emitting diode display comprising an organic EL element having an anode connected to a drain terminal of the anode and a cathode connected to an electrode of the potential of the electrostatic potential, and a pixel circuit having a capacitor for charge accumulation connected at one end to a connection point of the drain terminal and the anode; A first method of driving a device, wherein the first transistor is turned on, the potential at the other end of the capacitor is maintained at a low potential at which no current flows through the organic EL element, and the data potential from the data line is accumulated as a charge in the capacitor. And the capacitor is turned off, and the capacitor The charge accumulated in the capacitor by the potential of the stage across the first vertical scanning period that increases up to a predetermined electric potential is characterized in that made in a second step for supplying the organic EL device.

In addition, a method of driving an organic light emitting diode display according to the present invention includes a first transistor and a first transistor formed at an intersection region of a data line and a gate line, a data line connected to a source terminal, and a gate line connected to a gate terminal. An organic light emitting diode display device comprising an organic EL element having an anode connected to a drain terminal, and a pixel circuit having a capacitor for charge accumulation connected at one end to a connection point of the drain terminal and the anode and connected to an electrode at a positive potential A first step of driving the first transistor, while maintaining the cathode potential of the organic EL element at a value higher than the initial anode potential, and accumulating the data potential from the data line as a charge in the capacitor. And the first transistor is turned off and the cathode of the organic EL element And a second step of supplying the charge accumulated in the capacitor to the organic EL element by lowering the depot potential to a predetermined potential over one vertical scanning period.

According to the organic light emitting diode display and the driving method thereof according to the present invention, during the on state period of the first transistor, the potential of the other end of the capacitor is maintained at a low potential at which no current flows in the organic EL element, and the data potential from the data line is maintained. Is accumulated in the capacitor as electric charge, and after the first transistor is turned off, the electric charge accumulated in the capacitor is supplied to the organic EL element by raising the potential of the other end of the capacitor to a predetermined potential over one vertical scanning period. do.

In addition, during the on state period of the first transistor, the cathode potential of the organic EL element is held at a value higher than the initial anode potential, and the first transistor is turned off while the data potential from the data line accumulates in the capacitor as a charge. After the state, the cathode potential of the organic EL element is lowered to a predetermined potential over one vertical scanning period so that the electric charge accumulated in the capacitor is supplied to the organic EL element.

Therefore, the drive current peak value of the organic EL element can be reduced and the current density can be reduced without using the drive transistor.

1A and 1B are schematic configuration diagrams illustrating an organic light emitting diode display according to Embodiment 1 of the present invention.
FIG. 2 is a circuit diagram illustrating a pixel circuit of the organic light emitting diode display shown in FIGS. 1A and 1B.
FIG. 3 is a timing chart showing an operation of the pixel circuit shown in FIG. 2.
4 is a circuit diagram showing a pixel circuit of an organic light emitting diode display according to Embodiment 2 of the present invention.
FIG. 5 is a timing chart showing the operation of the pixel circuit shown in FIG. 4.
6 is a circuit diagram of a pixel circuit of an organic light emitting diode display according to Embodiment 3 of the present invention.
FIG. 7 is a timing chart showing the operation of the pixel circuit shown in FIG. 6.
8 is an explanatory diagram showing Vg-Id characteristics of a general driving transistor in a conventional organic light emitting diode display.
9 is an explanatory diagram showing the relationship between the luminous efficiency of a general organic EL element in a conventional organic light emitting diode display, the power consumption of the organic EL element, and the ratio of the power consumed by the TFT substrate to the total power consumption. .

EMBODIMENT OF THE INVENTION Hereinafter, although preferred embodiment of the organic light emitting diode display which concerns on this invention is described using drawing, the same or corresponding part in each figure is attached | subjected and demonstrated with the same code | symbol.

In the organic light emitting diode display of the present invention, in the organic EL elements of each pixel circuit, a constant current is flowed over one vertical scanning period (hereinafter, 1V period), thereby securing the amount of charge necessary for light emission of the organic EL element. Even in the case where the driving current range is narrow, current control is easy, and low power consumption and long life can be realized.

Embodiment 1

1A and 1B are schematic configuration diagrams illustrating an organic light emitting diode display 100 according to Embodiment 1 of the present invention. In FIG. 1A, the organic light emitting diode display 100 includes a display panel 10, a gate line driving circuit 20, a data line driving circuit 30, and an emission control line driving circuit 40. (Light emission control unit).

1B, a plurality of gate lines 21 are connected to the gate line driving circuit 20 in the horizontal direction, and a plurality of data lines 31 are connected to the data line driving circuit 30 in the vertical direction. A plurality of emission control lines 41 are connected to the emission control line driving circuit 40 in the horizontal direction.

The gate line driving circuit 20, the data line driving circuit 30, and the emission control line driving circuit 40 apply driving of the gate line 21, the data line 31, and the emission control line 41, respectively. It is controlled by the electric potential.

In addition, a plurality of pixel circuits 50 are formed in each intersection region of the plurality of gate lines 21 and the plurality of data lines 31. The pixel circuit 50 is formed corresponding to the three primary colors of red, green, and blue, respectively, and the three pixel circuits 50 constitute one pixel. Here, in FIG. 1B, three pixels are extracted from the plurality of pixels.

FIG. 2 is a circuit diagram illustrating a pixel circuit 50 of the organic light emitting diode display 100 shown in FIGS. 1A and 1B. In FIG. 3, the pixel circuit 50 includes a selection transistor 51 (first transistor), an organic EL element 52, and a capacitor 53. That is, the pixel circuit 50 is comprised by 1Tr 1C type.

The select transistor 51 is formed at the intersection of the data line 31 and the gate line 21. Further, the source terminal of the select transistor 51 is connected to the data line 31, the gate terminal is connected to the gate line 21, and the drain terminal is connected to one end of the anode and the capacitor 53 of the organic EL element 52. It is.

The anode of the organic EL element 52 is connected to the drain terminal of the selection transistor 51 and the cathode is connected to the electrode of the positive potential. One end of the capacitor 53 is connected to the connection point of the drain terminal of the selection transistor 51 and the anode of the organic EL element 52, and the other end thereof is connected to the emission control line 41.

Subsequently, the operation of the pixel circuit 50 shown in FIG. 2 will be described with reference to the timing chart of FIG. 3. 3 represents the time, the vertical axis represents the potential of the gate line 21, the potential of the data line 31, the potential of the emission control line 41, and the current Ioled flowing through the organic EL element 52. .

First, when the gate line 21 is activated ("L") by the gate line driving circuit 20, the selection transistor 51 is turned on so that the data potential, which is a video signal from the data line 31, becomes a node ( Vano). At this time, the emission control line driving circuit 40 applies a potential of the emission control line 41 to the organic EL element 52 so that the data potential from the data line 31 is accumulated in the capacitor 53 as a charge. Maintain a low potential that does not flow.

That is, the emission control line driving circuit 40 stores the anode potential (Vano) before voltage boosting so that no charge is supplied from the capacitor 53 to the organic EL element 52 when the charge is accumulated in the capacitor 53. It is maintained at a value (Vano < Vcat + Vtold) lower than the sum (Vcat + Vtold) of the cathode potential Vcat and the threshold voltage value potential Vtoled of the element 52. As a result, the data potential from the data line 31 is accumulated in the capacitor 53 as electric charge.

Here, the charges accumulated in the capacitor 53 are charges necessary for the organic EL element 52 to emit desired luminance in the 1V period. Specifically, in order for the organic EL element 52 to emit desired luminance, the capacitance of the capacitor 53 needs to satisfy the following expression (1).

In Equation 1, Cp denotes the capacitance of the capacitor 53, Ipeak denotes the set peak current of the organic EL element 52, fc denotes the driving frequency, and Vb is applied to both ends of the capacitor 53. The voltage to be shown is shown.

Subsequently, when the gate line 21 is deactivated ("H") by the gate line driver circuit 20, the selection transistor 51 is turned off, and the charge accumulation to the capacitor 53 ends. At this time, the emission control line driving circuit 40 raises the potential of the emission control line 41 to a predetermined potential over the 1V period until the next selection transistor 51 is turned on.

Here, the predetermined potential is a potential (Vano ≥ Vcat + Vtold) at which the anode potential Vano becomes a cathode potential of the organic EL element 52 equal to or more than the sum of the threshold voltage (Vcat + Vtoled), and is applied to the capacitor 53. All the accumulated charges are set to potentials that can be supplied to the organic EL elements 52 as drive currents. As a result, the electric charge accumulated in the capacitor 53 is converted into light in the organic EL element 52 to emit desired luminance.

In addition, the emission control line driving circuit 40 raises the potential of the emission control line 41 over the 1V period, and supplies the charge accumulated in the capacitor 53 to the organic EL element 52 at low speed. As a result, as shown in FIG. 3, the driving current that is leveled flows through the organic EL element 52.

As described above, according to the first embodiment, during the on state period of the first transistor, the anode potential Vano of the organic EL element is larger than the sum of the cathode potential Vcat and the threshold voltage value potential Vtoled of the organic EL element. It is held at a low value (Vano < Vcat + Vtoled), the data potential from the data line accumulates in the capacitor as a charge, and after the first transistor is turned off, the other end potential of the capacitor is predetermined for 1 V period. The electric charge accumulated in the capacitor is supplied to the organic EL element by being raised to the potential of.

Therefore, the drive current peak value of the organic EL element can be reduced and the current density can be reduced without using the drive transistor.

In addition, since the driving charge is accumulated in the capacitor without using the driving transistor, the luminance control can be easily realized even when the microcurrent control is unnecessary and the luminous efficiency of the organic EL element is further improved in the long term.

In addition, since there is no power consumption due to the on-resistance without using the driving transistor, the power consumed by the TFT substrate can be reduced to realize low power consumption.

Furthermore, by controlling the amount of electric charge supplied to the organic EL element, the peak value of the driving current can be reduced, the current density can be reduced, and the long life can be realized.

Embodiment 2

4 is a circuit diagram showing a pixel circuit 50A of the organic light emitting diode display according to Embodiment 2 of the present invention. In FIG. 4, the pixel circuit 50 (A) includes a selection transistor 51, an organic EL element 52, and a capacitor 53.

The anode of the organic EL element 52 is connected to the drain terminal of the selection transistor 51 and the cathode is connected to the emission control line 41. One end of the capacitor 53 is connected to the drain terminal of the selection transistor 51 and the anode connection point of the organic EL element 52, and the other end thereof is connected to the electrode of the positive potential. In addition, the other structure is the same as that of Embodiment 1 mentioned above, and abbreviate | omits description.

The operation of the pixel circuit 50A shown in FIG. 4 will be described with reference to the timing chart of FIG. 5. 5 represents the time, and the vertical axis represents the potential of the gate line 21, the potential of the data line 31, the potential of the emission control line 41, and the current flowing through the organic EL element 52. Indicates.

First, when the gate line 21 is activated ("L") by the gate line driver circuit 20, the selection transistor 51 is turned on, so that the data potential of the video signal from the data line 31 is a node. It is input to (Vano). At this time, the emission control line driving circuit 40 applies a potential of the emission control line 41 to the organic EL element 52 so that the data potential from the data line 31 is accumulated in the capacitor 53 as a charge. Maintain a high potential that does not flow.

That is, the emission control line driving circuit 40 has a potential of the emission control line 41 so that no charge is supplied from the capacitor 53 to the organic EL element 52 when the charge is accumulated in the capacitor 53. Vec is maintained at a higher value (Vec> Vano-Vtoled) than the difference (Vano-Vtoled) between the anode potential Vano of the step-down and the threshold voltage value potential Vtoled of the organic EL element 52. As a result, the data potential from the data line 31 is accumulated in the capacitor 53 as electric charge.

Here, the charge accumulated in the capacitor 53 is a charge necessary for the organic EL element 52 to emit a desired luminance in the 1V period. Specifically, in order for the organic EL element 52 to emit desired luminance, the capacitance of the capacitor 53 needs to satisfy the above expression (1).

Subsequently, when the gate line 21 is inactivated ("H") by the gate line driver circuit 20, the selection transistor 51 is turned off, and the accumulation of charges in the capacitor 53 ends. At this time, the emission control line driving circuit 40 lowers the potential of the emission control line 41 to a predetermined potential over a 1V period.

Here, the predetermined potential is a potential at which the organic EL element 52 which is a pn junction diode is conducted (the difference between the anode potential Vano and the threshold voltage value potential Vtoled of the organic EL element 52 (Vano-Vtoled)). Hereinafter, all electric charges accumulated in the capacitor 53 are set to potentials that can supply the organic EL element 52 as a driving current. As a result, the electric charge accumulated in the capacitor 53 is converted into light in the organic EL element 52 to emit desired luminance.

In addition, the emission control line driving circuit 40 lowers the potential of the emission control line 41 over a period of 1 V, and supplies the charge accumulated in the capacitor 53 to the organic EL element 52 at low speed. As a result, as shown in FIG. 5, the driving current that is leveled flows through the organic EL element 52.

As described above, according to the second embodiment, during the on state period of the first transistor, the cathode potential of the organic EL element is high such that a current does not flow from the node Vano of the capacitor to the organic EL element (anode of the piezoelectric element). It is held at a value higher than the difference between the potential and the threshold voltage value potential of the organic EL element (Vec> Vano-Vtoled), and the first transistor is turned off while the data potential from the data line accumulates in the capacitor as a charge. After the state, the cathode potential of the organic EL element is lowered to a predetermined potential over a 1 V period, so that the charge accumulated in the capacitor is supplied to the organic EL element.

Therefore, the same effect as that of Embodiment 1 mentioned above can be obtained.

Embodiment 3

6 is a circuit diagram showing a pixel circuit 50B of the organic light emitting diode display according to Embodiment 3 of the present invention. In FIG. 6, the pixel circuit 50B includes a selection transistor 51, an organic EL element 52, a capacitor 53, and a switch transistor 54 (second transistor).

The select transistor 51 is formed at the intersection of the data line 31 and the gate line 21. In addition, the source terminal of the selection transistor 51 is connected to the data line 31, the gate terminal is connected to the gate line 21, and the drain terminal is connected to one end of the capacitor 53 and the source terminal of the switch transistor 54. It is.

The gate terminal of the switch transistor 54 is connected to the emission switch line 55 and the drain terminal is connected to the anode of the organic EL element 52. The cathode of the organic EL element 52 is connected to the emission control line 41. One end of the capacitor 53 is connected to the connection point of the drain terminal of the selection transistor 51 and the source terminal of the switch transistor 54, and the other end thereof is connected to the electrode of the potential of the electrostatic potential.

Here, the emission switch line 55 is provided in the vicinity of the gate line driving circuit 20 or the emission control line driving circuit 40 and controlled by a potential for applying the drive of the emission switch line 55. It is connected to an emission switch line drive circuit (not shown). In addition, other structure is the same as that of Embodiment 2 mentioned above, and abbreviate | omits description.

Next, the operation of the pixel circuit 50B shown in FIG. 6 will be described with reference to the timing chart of FIG. 7. 7 represents the time, and the vertical axis represents the potential of the gate line 21, the potential of the data line 31, the potential of the emission control line 41, the potential of the emission switch line 55, and the organic EL. The current Ioled flowing through the element 52 is shown.

First, when the gate line 21 is activated ("L") by the gate line driver circuit 20, the selection transistor 51 is turned on, so that the data potential of the video signal from the data line 31 is a node. Entered in (Vdata). At this time, the emission control line driving circuit 40 keeps the potential of the emission control line 41 at the value higher than the initial anode potential Vano.

In addition, the emission switch line driving circuit deactivates the emission switch line 55 to block the capacitor 53 and the organic EL element 52 at the timing when the gate line 21 is activated (“L”). "H"), and the switch transistor 54 is turned off.

Here, the charge accumulated in the capacitor 53 is a charge necessary for the organic EL element 52 to emit a desired luminance in the 1V period. Specifically, in order for the organic EL element 52 to emit desired luminance, the capacitance of the capacitor 53 needs to satisfy the above expression (1).

Subsequently, when the gate line 21 is inactivated ("H") by the gate line driver circuit 20, the selection transistor 51 is turned off, and the accumulation of charges in the capacitor 53 ends. At this time, the emission control line driving circuit 40 lowers the potential of the emission control line 41 to a predetermined potential over a 1V period.

In addition, the emission switch line driving circuit activates the emission switch line 55 so that the capacitor 53 and the organic EL element 52 are connected at a timing at which the gate line 21 is inactivated (“H”). &Quot; L " to turn the switch transistor 54 on.

Here, the predetermined potential is a potential at which the organic EL element 52 which is a pn junction diode is conducted (the difference between the anode potential Vano and the threshold voltage value potential Vtoled of the organic EL element 52 (Vano-Vtoled)). Hereinafter, all electric charges accumulated in the capacitor 53 are set to potentials that can supply the organic EL element 52 as a driving current. As a result, the electric charge accumulated in the capacitor 53 is converted into light in the organic EL element 52 to emit desired luminance.

In addition, the emission control line driving circuit 40 lowers the potential of the emission control line 41 over a period of 1V, and supplies the charge accumulated in the capacitor 53 to the organic EL element 52 at a low speed. As a result, as shown in FIG. 7, the driving current that is leveled flows through the organic EL element 52.

As described above, according to the third embodiment, during the on state period of the first transistor, the cathode potential of the organic EL element is held at a value higher than the initial anode potential Vano, and the data potential from the data line is the charge. After the first transistor is turned off and the cathode potential of the organic EL element is lowered to a predetermined potential over a period of 1 V, the charge accumulated in the capacitor is supplied to the organic EL element. .

Further, the pixel circuit is connected between the drain terminal of the first transistor, the connection point of the capacitor, and the organic EL element, and is turned off when the first transistor is on, and is turned on when the first transistor is off. A second transistor in a state is provided.

Therefore, the same effects as those of the second embodiment described above can be obtained, and when electric charges are accumulated in the capacitors, the electric charges are supplied from the capacitors to the organic EL elements by the difference in the threshold voltage value potential of the organic EL elements. You can prevent it.

On the other hand, in the first to third embodiments, the emission control line driving circuit 40 described that the potential of the emission control line 41 is raised to a predetermined potential over a 1 V period, but the present invention is not limited thereto. The emission control line driving circuit 40 may raise the potential of the emission control line 41 to a predetermined potential several times in the 1V period.

10 display panel 20 gate line driving circuit
21: gate line 30: data line driving circuit
31: data line 40: emission control line drive circuit
41: emission control line 50, 50A, 50B: pixel circuit
51: select transistor 52: organic EL element
53: Capacitor 54: Switch Transistor
55: emission switch line (switch line)
100: organic light emitting diode display

Claims (18)

A first transistor formed at an intersection region of the data line and the gate line, the data line connected to a source terminal, and the gate line connected to a gate terminal;
An organic EL element in which an anode is connected to a drain terminal of the first transistor and a cathode is connected to an electrode of a potential potential; and
A pixel circuit having a capacitor for charge accumulation having one end connected to a connection point of the drain terminal and the anode;
An emission control line connected to the other end of the capacitor,
During the on state period of the first transistor, the potential of the emission control line is maintained at a low potential at which no current flows in the organic EL element, and after the first transistor is turned off, And a light emission controller for raising the potential to a predetermined potential over one vertical scanning period. The organic light emitting diode display device according to claim 1, wherein the predetermined potential is a potential equal to or more than the sum of the cathode potential and the threshold voltage value potential of the organic EL element. The organic light emitting diode display of claim 1, wherein the emission control unit raises the potential of the emission control line to the predetermined potential several times in one vertical scanning period. A first transistor formed at an intersection region of the data line and the gate line, the data line connected to a source terminal, and the gate line connected to a gate terminal;
An organic EL element having an anode connected to a drain terminal of the first transistor, and
A pixel circuit having a capacitor for accumulating charge, one end of which is connected to a connection point of the drain terminal and the anode, and the other end of which is connected to an electrode of a potential potential;
An emission control line connected to the cathode of the organic EL element,
During the on state period of the first transistor, the potential of the emission control line is maintained at a value higher than an initial anode potential, and the potential of the emission control line is vertically scanned after the first transistor is turned off. An organic light emitting display device comprising: a light emission control unit for lowering to a predetermined potential over a period of time. The organic light emitting diode display according to claim 4, wherein the predetermined potential is equal to or less than a potential at which the organic EL element is conducted. The organic light emitting diode display of claim 4, wherein the emission control unit lowers the potential of the emission control line to the predetermined potential several times in one vertical scanning period. The organic light emitting diode display device according to claim 1 or 4, wherein the predetermined potential is a potential for supplying all of the charge accumulated in the capacitor to the organic EL element as a driving current. The charge accumulated in the capacitor according to claim 1 or 4, wherein the following formula Cp≥Ipeak x fc / Vb, where Cp is the capacitance of the capacitor, Ipeak is the set peak current, fc is the driving frequency, and Vb. Is a potential applied to both ends of the capacitor). 5. The pixel circuit according to claim 1 or 4, wherein the pixel circuit is connected between a connection point of the drain terminal and the capacitor and the organic EL element, and is turned off when the first transistor is turned on, and the first A second transistor, which is turned on when the transistor is in an off state;
And a drain terminal of the second transistor is connected to an anode of the organic EL element. A first transistor formed at an intersection region of the data line and the gate line, the data line connected to a source terminal, and the gate line connected to a gate terminal;
An organic EL element in which an anode is connected to a drain terminal of the first transistor and a cathode is connected to an electrode of a potential potential; and
A driving method of an organic light emitting diode display device comprising a pixel circuit having a capacitor for charge accumulation having one end connected to a connection point of the drain terminal and the anode,
A first step of turning on the first transistor and maintaining a potential at the other end of the capacitor at a low potential at which no current flows in the organic EL element, and accumulating the data potential from the data line as a charge in the capacitor; Wow,
A second step of supplying the electric charge accumulated in the capacitor to the organic EL element by turning off the first transistor and raising the potential at the other end of the capacitor to a predetermined potential over one vertical scanning period; Method of driving an organic light emitting diode display, characterized in that made. The method of driving an organic light emitting diode display device according to claim 10, wherein the predetermined potential is a potential equal to or more than the sum of the cathode potential and the threshold voltage value potential of the organic EL element. The method of claim 10, wherein the second step raises the potential of the other end of the capacitor to the predetermined potential several times in one vertical scanning period. A first transistor formed at an intersection region of a data line and a gate line, the data line connected to a source terminal, and the gate line connected to a gate terminal;
An organic EL element having an anode connected to a drain terminal of the first transistor, and
A driving method of an organic light emitting diode display device comprising a pixel circuit having one end connected to a connection point of the drain terminal and an anode and the other end connected to an electrode of a potential potential, arranged in a pixel circuit;
A first step of turning on the first transistor and maintaining a cathode potential of the organic EL element at a value higher than an initial anode potential and accumulating the data potential from the data line as a charge in the capacitor; ,
A second for supplying the electric charge accumulated in the capacitor to the organic EL element by turning off the first transistor and simultaneously lowering the cathode potential of the organic EL element to a predetermined potential over one vertical scanning period; A method of driving an organic light emitting diode display, comprising the steps of: The method of driving an organic light emitting diode display device according to claim 13, wherein the predetermined potential is equal to or less than a potential at which the organic EL element is conductive. The method of claim 13, wherein the second step lowers the potential of the other end of the capacitor to the predetermined potential several times in one vertical scanning period. The method of driving an organic light emitting diode display device according to claim 10 or 13, wherein the predetermined potential is a potential for supplying all the charges accumulated in the capacitor to the organic EL element as a driving current. The charge accumulated in the capacitor according to claim 10 or 13, wherein the following formula Cp≥Ipeak x fc / Vb (where Cp is the capacitance of the capacitor, Ipeak is the set peak current, fc is the driving frequency, and Vb). Is a potential applied to both ends of the capacitor). 14. The pixel circuit according to claim 10 or 13, wherein the pixel circuit further includes a second transistor between a connection point of the drain terminal and the capacitor and the organic EL element, and the first step turns off the second transistor. To a state, wherein the second step comprises turning on the second transistor;
And a drain terminal of the second transistor is connected to an anode of the organic EL element.

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