JP2005308897A - Display device and its drive method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the rise of light emission without lowering the maximum luminance to be output by a display device irrespective of the pulse width for the gradation control. <P>SOLUTION: The organic EL display having organic EL elements formed at and connected to both electrodes formed at the crossing point of the data electrodes and the scanning electrodes arranged in a matrix is driven by controlling the gradations by the pulse width of the drive signal supplied to the data electrode. At this point, the selected scanning electrode is brought to the ground level, and by supplying the positive voltage lower than the reverse bias voltage to the selected scanning electrode until the next scanning electrode is chosen, and further supplying the voltage lower than the luminescence threshold voltage of the organic EL device to the data electrode until the drive signals are supplied, and charging before selecting the light emitting element connected to the scanning electrode to be selected next, the next scanning electrode can be selected while charging. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display device and a driving method thereof, and is particularly suitable for an organic EL display device using an organic electroluminescence (hereinafter also referred to as “EL”) element as a light emitting element.

  BACKGROUND ART An organic EL display device is a display device using an organic EL element that utilizes an EL phenomenon of an organic thin film as a light emitting element, and has attracted attention as a self-luminous display device. The organic EL display device includes a plurality of data electrodes parallel to each other, a plurality of scan electrodes provided in a direction orthogonal to the data electrodes, and a plurality of data electrodes formed at intersections of the data electrodes and the scan electrodes. An organic EL display including an organic EL element is included. That is, the organic EL display of the organic EL display device displays an image by a plurality of organic EL elements formed at each intersection of the data electrode and the scanning electrode arranged in a matrix.

  In the conventional passive matrix driving method (simple matrix driving method) employed as the driving method of the organic EL display device described above, one frame period is divided by the number of scanning lines (number of scanning electrodes) N, and the N division is performed. So-called line-sequential driving is performed in which one scanning line (scanning electrode) is sequentially driven every period. Specifically, the potentials of the scanning lines to be displayed are selected by sequentially setting them to 0 V, and the other (N-1) non-selected scanning lines are selected so as not to emit light. A reverse bias voltage is applied so that the terminal voltage is equal to or lower than the light emission threshold voltage. For gradation control, a pulse width method is used in which gradation control is performed with the application time of the current applied to the data line (data electrode), that is, the pulse width applied to the data line.

  Here, in the organic EL display device, the organic EL element which is a light emitting element has a capacitive component. For this reason, in the above-described passive matrix driving method, there is a problem that the capacitance component of the organic EL element acts as a capacitor, and the rise of light emission is delayed with respect to voltage application.

In order to solve this problem, a driving method for improving the rising characteristics of light emission in an organic EL element has been proposed (for example, see Patent Documents 1 and 2).
Patent Document 1 discloses a driving method using both constant voltage driving and constant current driving. As shown in FIG. 8A, first, the organic EL element is charged by driving at a constant voltage, Then switch to constant current drive. However, in this driving method, a charging time (period) for charging the organic EL element by applying a constant voltage within the period during which the scanning line is selected (hereinafter also referred to as “selection period”) TSEL. Tch) is required. Therefore, the time during which the organic EL element actually contributes to light emission (period TEmax) is shorter than the selection period TSEL, and the luminance is lower than when all of the selection period is spent for light emission.

  Further, as shown in FIG. 8B, Patent Document 2 discloses a driving method in which an organic EL element is charged by applying an offset voltage before scanning the next scanning line. Even in this driving method, since the charging time (period Tch) for charging the organic EL element is provided in the selection period TSEL, the time during which the organic EL element contributes to light emission (period TEmax) is shorter than the selection period TSEL. Thus, the brightness is lower than when the entire selection period is spent for light emission.

  Here, the substantial selection period of each scanning line becomes shorter as the total number of scanning lines increases, and the charging time for charging the organic EL element is selected as in the driving methods disclosed in Patent Documents 1 and 2 above. If it is provided within the period, the ratio of the charging time to the light emission time becomes relatively large, which causes a significant problem.

  As one method for solving this problem, a driving method is proposed in which each electrode is driven as shown in FIG. 9A to charge the organic EL element connected to the next selected scanning electrode in advance. (For example, see Patent Document 3). In the driving method disclosed in Patent Document 3, the voltage V1 applied from the data electrode during selection and the reverse bias voltage V1 applied to the scan electrode in the non-selected state during the selection period TSEL1 and TSEL2 of a certain scan electrode. A low voltage V2 is applied to the next selected scan electrode. Accordingly, the organic EL element connected to the next selected scan electrode can be charged in advance with a voltage difference (V2−V1) larger than 0V while allowing the entire selection period to contribute to light emission. (Refer to periods Tch1 and Tch2.)

Japanese Patent Laid-Open No. 11-231834 Japanese Patent Laid-Open No. 11-143429 JP 2001-125538 A

  However, in the driving method disclosed in Patent Document 3, when gradation control is performed with the pulse width applied to the data electrode, the pulse width is the maximum, that is, except when the gradation is the maximum gradation, as shown in FIG. The voltage of the selected data electrode becomes the ground level (0 V) during the selection period (period Tg in the period TSEL1). Therefore, the voltage difference applied to the organic EL element connected to the next selected scan electrode is inverted and becomes 0 <V2, so that the charged charge is discharged, and the light emission rise by charging is not improved. Patent Document 3 discloses a driving method in which all data electrode selection periods are provided to perform preliminary charging. However, by providing this all data electrode selection period, the actual light emission time is shortened and the luminance is lowered.

  The present invention has been made in view of such problems, and the light emission rise of the light emitting element is achieved without reducing the maximum luminance that can be output by the display device regardless of the pulse width for gradation control. To be able to improve.

The display device of the present invention includes a display means having a plurality of data electrodes and scan electrodes, a light emitting element formed at each intersection of the data electrodes and the scan electrodes, and connected to both electrodes, and a first potential. Is supplied to the selected scanning electrode, and the third potential lower than the second potential applied to the non-selected scanning electrode and higher than the first potential is selected next. Scanning electrode driving means for supplying an electrode, and data electrode driving means for supplying a data electrode driving signal having a fourth potential to the data electrode, and controlling gradation at least by a pulse width of the data electrode driving signal. In addition, the data electrode driving signal is supplied to the data electrode until the next selected scanning electrode is selected, and the data electrode driving signal is supplied to the data electrode. In a fifth potential difference is smaller than the light emission threshold voltage with respect to the reference potential of the light emitting device and supplying to the data electrode.
According to the above configuration, the light emitting element connected to the next selected scan electrode can be charged in advance before selection by the potential difference between the next selected scan electrode potential and the data electrode drive signal, and By supplying the data electrode drive signal until the scan electrode is selected, the scan electrode can be selected while the light emitting element is charged.

  According to the present invention, the data electrode driving signal is supplied until the next selected scan electrode is selected, so that the selected scan electrode is connected to the next selected scan electrode while driving. The charged light emitting element can be charged in advance, and the next scanning electrode can be selected while the light emitting element is charged. Therefore, the entire period during which the scan electrode is selected can contribute to light emission, the light emitting element can be charged without lowering the maximum luminance that can be output by the display device, and the gradation can be controlled. The charge state can be maintained regardless of the pulse width of the data electrode drive signal, and the light emission rise of the light emitting element can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration example of a display device according to an embodiment of the present invention. In the present embodiment, an organic EL display device that uses an organic EL element as a light emitting element and performs gradation control by a pulse width with a passive matrix driving method will be described as an example.

  The organic EL display device according to this embodiment includes an organic EL display 1, a data electrode driving circuit 2 and a scanning electrode driving circuit 3 for driving the organic EL display 1, and a data electrode driving circuit 2 and a scanning electrode driving circuit 3. And a control circuit 4 for controlling.

  The organic EL display 1 includes data electrodes (anodes) X1 to Xm as data lines arranged so as to be parallel to each other, and scanning lines arranged so as to be parallel to each other in a direction orthogonal to the data electrodes X1 to Xm. As scanning electrodes (cathodes) Y1 to Yn. In addition, the organic EL display 1 includes a plurality of organic EL elements Eij as light emitting elements that are formed at the intersections of the data electrodes Xi and the scanning electrodes Yj and connected to the two electrodes. Note that i and j are subscripts, i = 1 to m, and j = 1 to n. That is, in the organic EL display 1, the organic EL elements Eij are formed at the intersections of the data electrodes X1 to Xm and the scanning electrodes Y1 to Yn, and a plurality of these are arranged in a two-dimensional matrix of m rows and n columns. A two-dimensional image is displayed by the organic EL element Eij.

  In FIG. 1, the organic EL element Eij is schematically shown by a diode Dij having an anode connected to the data electrode Xi and a cathode connected to the scan electrode Yj, and a capacitor Cij connected in parallel thereto. A voltage equal to or higher than the light emission threshold voltage is applied in the forward direction by the data electrode drive circuit 2 and the scan electrode drive circuit 3 to the organic EL element Eij to emit light, and a current flows. Emits light with high brightness.

  The data electrode drive circuit 2 is a drive circuit for driving the data electrodes X1 to Xm by outputting drive signals to the data electrodes X1 to Xm, and switches SWX1 to SWXm provided for the respective data electrodes X1 to Xm. Prepare. Each switch SWX1 to SWXm has four terminals, the first terminal (movable contact) is connected to each data electrode X1 to Xm, and the second to fourth fixed terminals (fixed contacts) are the current source 11, respectively. The voltage source 12 that supplies the charge maintaining voltage Vd1 is connected to a reference potential (ground level). Although not shown, the drive voltage Vd is supplied to the current source 11, and the current source 11 supplies a constant current whose voltage becomes the drive voltage Vd to the data electrodes X1 to Xm. The charge maintaining voltage Vd1 is a voltage that is higher than the reference potential and that has a potential difference with the reference potential that is equal to or lower than the light emission threshold voltage of the organic EL element.

  The scan electrode drive circuit 3 is a drive circuit for outputting a drive signal and sequentially scanning the scan electrodes Y1 to Yn (line-sequential scan), and switches SWY1 to SWYn provided for the scan electrodes Y1 to Yn. Is provided. Each of the switches SWY1 to SWYn has four terminals, the first terminal (movable contact) is connected to each scanning electrode Y1 to Yn, and the second to fourth fixed terminals (fixed contacts) are respectively reverse bias voltages Vs. Are connected to a voltage source 21 for supplying voltage, a voltage source 22 for supplying drive voltage Vs1 for charging, and a reference potential (ground level).

  The control circuit 4 is connected to the data input terminal 5 and controls the data electrode driving circuit 2 and the scan electrode driving circuit 3 based on display data input via the data input terminal 5.

Next, an outline of a driving method and operation of the organic EL display device shown in FIG. 1 will be described.
FIG. 2 is a timing chart showing an example of drive waveforms of the organic EL display device according to the present embodiment. In FIG. 2, the drive signal applied to the data electrode is shown only for the period (selection period) TS1 in which the scan electrode Y1 is selected for convenience of explanation, but the drive signal corresponding to the data to be displayed is It is applied to the data electrode during the selection period of each of the scanning electrodes Y1 to Yn.

  As shown in FIG. 2, the scan electrodes Y1 to Yn are selected and sequentially driven by supplying a ground level drive signal at regular time intervals. Further, when the scan electrodes Y1 to Yn are scan electrodes to be selected next, that is, during the selection period of the previous scan electrode, the drive signal of the drive voltage Vs1 is supplied. Accordingly, the scan electrodes Y1 to Yn are at the voltage Vs1 in the selection period immediately before their own selection period, and the voltage is at the ground level in their selection period. In other periods, the potentials of the scan electrodes Y1 to Yn are Vs. Note that the period from the start of the selection period of the scan electrode Y1 to the end of the selection period of the scan electrode Yn corresponds to a period TF for one frame.

  As described above, the drive signals corresponding to the data to be displayed are applied to the data electrodes X1 to Xm during the selection period of the scan electrodes Y1 to Yn. Specifically, when the organic EL element Eij, which is a light emitting element, emits light, a driving signal of the driving voltage Vd is supplied to the data electrodes X1 to Xm, and when the light emitting element does not emit light, the driving signal of the driving voltage Vd1 is supplied. Supplied.

  Here, in the organic EL display device according to this embodiment, the time for applying the drive signal of the drive voltage Vd to the data electrodes X1 to Xm, that is, the pulse width of the drive signal of the drive voltage Vd to the data electrodes X1 to Xm. Gradation control related to the display image is performed. For example, when light is emitted with high luminance, the pulse width of the drive signal of the drive voltage Vd is lengthened, and when light is emitted with low luminance, the pulse width is shortened. Furthermore, the drive signal of the drive voltage Vd applied to the data electrodes X1 to Xm is applied until the selection period of the next scan electrode, in other words, the time between the end of the current selection period and the drive signal of the drive voltage Vd. Apply to match the end (end). Therefore, the drive signal of the drive voltage Vd1 is supplied to the data electrodes X1 to Xm according to the gradation, and then the drive signal of the drive voltage Vd is supplied until the end of the selection period.

Next, as a specific example, a driving method and operation of the organic EL display device when driving with a driving waveform as shown in FIG. 3 will be described.
FIG. 3 is a diagram illustrating an example of a driving waveform for specifically explaining the driving method and operation of the organic EL display device according to the present embodiment. The scanning electrode Y1 is scanned in the selection period TSEL1, and the organic EL element is scanned. The drive waveforms in the case where the organic EL elements E12 to Em2 are caused to emit light by scanning the scan electrode Y2 in the next selection period TSEL2 after causing E11 to Em1 to emit light are shown.

  In the selection period TSEL1 shown in FIG. 3, the switch SWY1 in the scan electrode drive circuit 3 is connected to the first terminal connected to the scan electrode Y1 and the fourth terminal connected to the ground level. The potential of the scanning electrode Y1 is selected as the ground level. Further, in the selection period TSEL1, the switch SWY2 is connected to the first terminal connected to the scanning electrode Y2 and the third terminal connected to the voltage source 22 of the driving voltage Vs1 for charging. The drive voltage Vs1 for charging is applied to the scan electrode Y2. At this time, the reverse bias voltage Vs supplied from the voltage source 21 is applied to the other scan electrodes Y3 to Yn excluding the scan electrodes Y1 and Y2.

  At time t1 in the selection period TSEL1, each of the switches SWX1 to SWXm in the data electrode drive circuit 2 is connected to the first terminal connected to the data electrodes X1 to Xm and the current source 11. Suppose that the terminal is connected. Therefore, the voltage of the data electrodes X1 to Xm is Vd.

  Here, the driving voltage Vs1 for charging applied to the scan electrode Y2 is set so as to satisfy the relationship of 0 <Vd−Vs1 <Voel and Vs1 <Vs. That is, it is set so as to be lower than the reverse bias voltage Vs applied to the scan electrode and the potential difference between the drive voltage Vd and the drive voltage Vs1 is less than the light emission threshold voltage Voel of the organic EL element.

  Therefore, as shown in FIG. 4, due to the potential difference between the scan electrode Y2 and the data electrodes X1 to Xm, parasitic capacitances (capacitors C12 to Cm2) of the organic EL elements E12 to Em2 connected to the scan electrode Y2 to be selected next. ) Is charged. Further, as described above, since the potential difference between the scanning electrode Y2 and the data electrodes X1 to Xm is less than the light emission threshold voltage Voel of the organic EL element, the organic EL elements E12 to Em2 emit light (erroneous light emission). There is no.

  The state at time t1 described above is maintained until the start of the next selection period TSEL2. Therefore, unlike the driving method disclosed in Patent Document 3, in this embodiment, the charges charged in the parasitic capacitances of the organic EL elements E12 to Em2 are discharged before the next selection period TSEL2 is started. Without being shifted to the selection period TSEL2.

  When the selection period TSEL1 ends and the selection period TSEL2 is reached, the switch SWY2 in the scan electrode drive circuit 3 is selected by connecting the first terminal and the fourth terminal, and the potential of the scan electrode Y2 becomes the ground level. The The switch SWY3 corresponding to the scan electrode Y3 has a first terminal and a third terminal connected to each other, and the drive voltage Vs1 for charging is applied to the scan electrode Y3. In the selection period TSEL2, the reverse bias voltage Vs is applied to the other scan electrodes Y1, Y4 to Yn.

  Here, in the selection period TSEL2, only the organic EL element E12 emits light with the maximum gradation, that is, the pulse width of the drive signal for applying the drive voltage Vd to the data electrode X1 is maximized, and all of the selection periods TSEL2 are selected. It is assumed that the drive voltage Vd is applied to the data electrode X1 during the period.

  In this case, at time t2, which is the start time of the selection period TSEL2, the switch SWX1 in the data electrode drive circuit 2 is connected to the first terminal and the second terminal, and the drive voltage Vd is connected to the data electrode X1. Is applied. Further, the switches SWX2 to SWXm corresponding to the data electrodes X2 to Xm whose pulse width of the drive signal of the drive voltage Vd is shorter than the maximum value depending on the data to be displayed are supplied to the voltage source 12 that supplies the first terminal and the charge maintaining voltage Vd1. The third terminal connected thereto is connected, and the charge sustaining voltage Vd1 is applied to the data electrodes X2 to Xm.

  Therefore, as shown in FIG. 5, since the parasitic capacitance C12 of the organic EL element E12 is already charged, the rise of the light emission of the organic EL element E12 is not delayed, and the light emission is started immediately, and all of the selection period TSEL2 It is possible to emit light during the period. Further, since the organic EL elements E22 to Em2 are applied with the charge maintaining voltage Vd1 satisfying the relationship of 0 <Vd1 <Voel as described above from the time t2 to the time t3 when the drive signal Vd is input. The charged charge is maintained without being discharged and does not emit light. In the period between time t2 and time t3, the parasitic capacitance C13 of the organic EL element E13 is charged by the potential difference between the data electrode X1 and the scanning electrode Y3.

  Next, at time t3, when the organic EL elements E22 to Em2 are instructed to emit light, the switches SWX2 to SWXm in the data electrode driving circuit 2 are connected to the first terminal and the second terminal, A drive voltage Vd is applied to the data electrodes X2 to Xm. Thereby, the organic EL elements E22 to Em2 emit light. Even when the organic EL elements E22 to Em2 are caused to emit light, as described above, the parasitic capacitances of the organic EL elements E22 to Em2 are already charged and the charges are maintained, so that the organic EL elements E22 to Em2 The rise of light emission is not delayed, and light emission starts immediately.

  Further, as shown in FIG. 6, due to the potential difference between the scan electrode Y3 and the data electrodes X1 to Xm, the organic EL elements E13 to Em3 connected to the next selected scan electrode Y3 do not emit light, and the parasitic The capacity is charged. Further, since the state at time t3 is maintained until the start of the next selection period TSEL3, the charges charged in the parasitic capacitances of the organic EL elements E13 to Em3 are discharged until the next selection period TSEL3 is started. There is nothing.

  As described above, according to the present embodiment, until the selection period of the next selected scan electrode Y1 to Yn starts in the selection period of a certain scan electrode Y1 to Yn (the next scan electrode Y1 to Yn is Until selected, a drive signal of the drive voltage Vd is supplied to the data electrodes X1 to Xm. As a result, the parasitic capacitance of the organic EL element connected to the next selected scan electrodes Y1 to Yn due to the potential difference between the voltage Vs1 of the next selected scan electrodes Y1 to Yn and the voltage Vd of the data electrodes X1 to Xm. Can be charged in advance, and the charge charged to the parasitic capacitance of the organic EL element can be transferred to the next selection period without being discharged. Therefore, there is no period used for charging within the selection period, all of the selection period can contribute to light emission, and the parasitic capacitance of the organic EL element can be charged without reducing the maximum displayable luminance. At the same time, as shown in FIG. 7, the emission rise of the organic EL element can be improved.

  FIG. 7A is a diagram showing the rise of light emission of the organic EL element in the present embodiment. For comparison, FIG. 7B shows the rise of light emission of the organic EL element in the conventional organic EL display device. ing. 7 (a) and 7 (b) show a data electrode side 320 lines × RGB, scan electrode side 240 lines organic EL display with a frame frequency of 60 MHz, a selection time per line set to 50 μs, and constant current drive ( The emission rising waveform of the organic EL element when it is 50 μA / pixel) is shown. As is apparent from a comparison between FIGS. 7A and 7B, in this embodiment, it can be seen that the emission rise of the organic EL element is very steep compared to the conventional case. In addition, the light emission rise time of the organic EL element in this embodiment is 3 μs, and the light emission rise time of the organic EL element according to the conventional technique is about 30 μs.

Further, for example, when the selection time per line is set to 50 μs and constant current driving (50 μA / pixel) is performed, the maximum luminance is 92 cd / m ² in the conventional technique, but according to the present embodiment, 120 cd. A maximum luminance of / m ² could be obtained.

  Note that this embodiment is very effective when the selection period per line is shortened, such as when the resolution is increased and the number of scanning electrodes (number of lines) is increased, and the luminance of the light emitting element is not lowered. It is possible to improve the emission rise.

  Each of the above embodiments is merely an example of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

It is a figure which shows the structural example of the organic electroluminescence display in one Embodiment of this invention. It is a timing chart which shows an example of the drive waveform of the organic electroluminescence display in this embodiment. It is a figure which shows an example of the specific drive waveform of the organic electroluminescent display apparatus in this embodiment. It is a figure for demonstrating operation | movement of the organic electroluminescence display in the period of the time t1-time t2 shown in FIG. It is a figure for demonstrating operation | movement of the organic electroluminescence display in the period of the time t2-time t3 shown in FIG. It is a figure for demonstrating operation | movement of the organic electroluminescent display apparatus in the period after the time t3 shown in FIG. It is a figure which shows the light emission rising of the organic EL element in the organic EL display apparatus in this embodiment. It is a figure which shows the drive waveform of the conventional organic EL display apparatus. It is a figure which shows the other drive waveform of the conventional organic EL display apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL display 2 Data electrode drive circuit 3 Scan electrode drive circuit 4 Control circuit 11 Current source 12 Charge maintenance voltage source 21 Drive voltage source 22 Charge voltage source X1-Xm Data electrode Y1-Yn Scan electrode E11-Emn Organic EL element

Claims (5)

A plurality of data electrodes; a scan electrode arranged to intersect the data electrode; and a light emitting element formed at each intersection of the data electrode and the scan electrode and connected to the data electrode and the scan electrode; Display means comprising:
A means for driving the scan electrodes line-sequentially, and supplying a first potential to the selected scan electrodes, and applying a second potential to the unselected scan electrodes different from the first potential Scan electrode driving means for supplying a third potential lower than the first potential and higher than the first potential to the next selected scan electrode;
Data electrode driving means for supplying a data electrode driving signal having a fourth potential to the data electrode;
While controlling gradation at least by the pulse width of the data electrode drive signal,
The data electrode driving means supplies the data electrode driving signal to the data electrode until the next selected scanning electrode is selected, and until the data electrode driving signal is supplied to the data electrode, A display device, wherein a fifth potential having a potential difference with respect to the reference potential smaller than a light emission threshold voltage of a light emitting element is supplied to the data electrode.   The potential difference between the fourth potential and the first potential is larger than the light emission threshold voltage, and the potential difference between the fourth potential and the second potential is positive and smaller than the light emission threshold voltage. The display device according to claim 1.   The display device according to claim 1, wherein the light emitting element is an organic electroluminescence element. A plurality of data electrodes; a scan electrode arranged to intersect the data electrode; and a light emitting element formed at each intersection of the data electrode and the scan electrode and connected to the data electrode and the scan electrode; Display means comprising:
A means for driving the scan electrodes line-sequentially, and supplying a first potential to the selected scan electrodes, and applying a second potential to the unselected scan electrodes different from the first potential Scan electrode driving means for supplying a third potential lower than the first potential and higher than the first potential to the next selected scan electrode;
Data electrode driving means for supplying a data electrode driving signal having a fourth potential to the data electrode;
While controlling gradation at least by the pulse width of the data electrode drive signal,
The data electrode driving means supplies the data electrode driving signal to the data electrode by matching the period during which the first potential is supplied to the scanning electrode and the end of the data electrode driving signal, and the data electrode A display device, wherein a fifth potential having a smaller potential difference with respect to the reference potential than a light emission threshold voltage of the light emitting element is supplied to the data electrode until a drive signal is supplied to the data electrode. A plurality of data electrodes; a scan electrode arranged to intersect the data electrode; and a light emitting element formed at each intersection of the data electrode and the scan electrode and connected to the data electrode and the scan electrode; A display device having a display means, and controlling a gray scale according to a pulse width of a drive signal supplied to at least the data electrode, comprising:
A first potential is supplied to the selected scan electrode to drive the scan electrode line-sequentially, and is lower than a second potential applied to the unselected scan electrode different from the first potential. And a third potential higher than the first potential is supplied to the next selected scan electrode,
The data electrode drive signal is supplied to the data electrode until the next selected scan electrode is selected, and the potential difference with respect to the reference potential is the light emission until the data electrode drive signal is supplied to the data electrode. A display device driving method, characterized in that a potential smaller than a light emission threshold voltage of the element is supplied to the data electrode.

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