JP2010224417A - Display device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To alleviate gradation in a display image. <P>SOLUTION: A light emitting element 640 emits light by driving current to be supplied from a driving transistor 620. Next, a writing transistor 610 applies extinction potential for performing extinction of the light emitting element 640 to a first node 650 equivalent to the gate terminal of the driving transistor 620. In accordance with impression of the extinction potential, an extinction auxiliary scanner 700 gives auxiliary potential for completely stopping light emission of the light emitting element 640 to one end of extinction capacity 670 via an extinction auxiliary line 710. The extinction capacity 670 reduces potential of a second node 660 equivalent to the input terminal of the light emitting element 640 connected to the other end of it by the auxiliary potential given to the one end of it. Thus, since the potential of the second node 660 becomes lower in comparison with threshold potential of the light emitting element 640, the extinction of the light emitting element 640 is performed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic device, and more particularly to a display device using a light emitting element as a pixel and an electronic device including the display device.

  In recent years, a flat self-luminous display device using an organic electroluminescence (EL) element as a light emitting element has been actively developed. This organic EL element emits light when an electric field is applied to the organic thin film, and has good visibility due to low voltage driving. Therefore, the organic EL element is expected to contribute to the reduction in the weight of the display device and the reduction in power consumption. Yes.

  In the display device using the organic EL element, the electric field applied to the organic thin film is controlled by the driving transistor constituting the pixel circuit. The threshold voltage and mobility of the driving transistor vary from individual to individual. . For this reason, a threshold correction process and a mobility correction process for correcting these individual differences are required, and thus a display device having such a correction process function has been devised. For example, there has been proposed a display device having a correction function for variations in threshold voltage and mobility of a driving transistor constituting a pixel circuit by switching a power supply signal and a data signal supplied to the pixel circuit (for example, Patent Documents). 1).

JP 2008-33193 A (FIG. 4A)

  In the above-described conventional technology, it is possible to correct variations in threshold voltage and mobility of the drive transistor that constitutes the pixel circuit. In this case, since the power supply signal is switched, a driver for switching the power supply signal is required for each row, which increases the cost of the display device. On the other hand, it is conceivable to reduce the number of drivers by adopting a configuration in which the power supply signal is switched every plural rows. However, in such a configuration, since the light emitting element is extinguished regardless of the switching of the power supply signal, it may take time to completely extinguish the light emitting element due to the influence of the parasitic capacitance of the light emitting element. In such a case, gradation may occur in the display image.

  The present invention has been made in view of such a situation, and an object thereof is to reduce gradation in a display image.

  The present invention has been made to solve the above problems, and a first aspect of the present invention is that a plurality of pixel circuits and a stop potential supply for supplying a stop potential for stopping light emission of the plurality of pixel circuits are provided. Each of the plurality of pixel circuits, a holding capacitor for holding a voltage corresponding to a video signal, a driving transistor for supplying a current corresponding to the voltage held in the holding capacitor, A light emitting element that emits light in response to a current supplied from the driving transistor, and a voltage corresponding to the video signal is written in the storage capacitor after applying a quenching potential for quenching the light emitting element to the gate terminal of the driving transistor. The write transistor and the stop potential supplied by the stop potential supply circuit are applied to one end of the extinction capacitor, and are connected to the other end of the extinction capacitor. A quenching capacitor that lowers the potential of the input terminal of the light emitting element, and the stop potential supply circuit has a lower potential than the potential when the light emitting element is emitting light during the quenching period for quenching the light emitting element. Display device and an electronic apparatus that supply the one end of the quenching capacitor as the stop potential. Thus, by providing a stop potential to one end of the quenching capacitor during the quenching period, the potential of the input terminal of the light emitting element connected to the other end of the quenching capacitor is lowered.

  The first aspect further includes a power supply circuit for supplying the same power supply potential to each of the plurality of pixel circuits for each of a plurality of rows, and the driving transistor receives the power supply potential to hold the power supply circuit. You may make it supply the electric current according to the voltage hold | maintained at the capacity | capacitance. This brings about the effect that the same power supply potential is supplied to the pixel circuits in a plurality of rows by the power supply circuit.

  In the first aspect, the signal processing circuit further includes a signal supply circuit that outputs the extinction potential in a period assigned by line-sequential scanning to each of the writing transistors of the plurality of pixel circuits, and the stop potential supply The circuit may supply the stop potential when the extinction potential is output from the signal supply circuit to the plurality of pixel circuits during the extinction period. Thus, when the extinction potential is output from the signal supply circuit to the plurality of pixel circuits during the extinction period, the stop potential is supplied by the stop potential supply circuit.

  In the first aspect, the stop potential supply circuit may supply the stop potential when the extinction potential is applied to the gate terminal of the drive transistor by the write transistor. Thus, when the extinction potential is applied to the gate terminal of the drive transistor by the writing transistor, the stop potential is supplied by the stop potential supply circuit.

  In the first aspect, the light emitting element may be composed of an organic electroluminescence element. This brings about the effect | action of making it light-emit by an organic electroluminescent element.

  In the first aspect, the quenching capacitor may be a capacitor for adjusting a correction speed when correcting the mobility of the driving transistor. As a result, there is an effect that the correction speed when the mobility of the driving transistor is corrected is set to an appropriate speed.

  According to the present invention, it is possible to achieve an excellent effect of reducing gradation in a display image.

It is a conceptual diagram which shows the basic structural example of the display apparatus used as the application object of embodiment of this invention. 3 is a diagram illustrating an example of a method for generating a power signal by drivers 401 to 403 constituting a power scanner (DSCN) 400 in the display apparatus 100. FIG. 3 is a diagram illustrating an example of a method for generating a data signal supplied to data lines (DTL) 311 to 313 by a horizontal selector (HSEL) 300 in the display device 100. FIG. 3 is a timing chart regarding an example of a basic operation of the display device 100. 3 is a circuit diagram schematically illustrating a configuration example of a pixel 600 in the display device 100. FIG. 3 is a timing chart regarding an example of a basic operation of a pixel 600 in the display device 100. It is a circuit diagram showing typically the operation state of pixel 600 corresponding to each period of TP8, TP1, and TP2. FIG. 6 is a circuit diagram schematically showing an operation state of a pixel 600 corresponding to each period of TP3 to TP5. FIG. 6 is a circuit diagram schematically showing an operation state of a pixel 600 corresponding to a period from TP6 to TP8. 12 is a timing chart illustrating the operation of the pixel 600 when the potential of the second node (ND2) 660 gradually decreases during the extinction period TP1 in the display device 100. FIG. 11 is a diagram related to a display image displayed on the display device 100 when the potential of the second node (ND2) 660 gradually decreases during the extinction period TP1 in the display device 100. It is a conceptual diagram which shows the example of 1 structure of the display apparatus 100 in the 1st Embodiment of this invention. 5 is a timing chart relating to an example of the operation of the pixel 600 according to the first embodiment of the present invention. It is a circuit diagram which shows typically the example of a structure of the pixel 600 provided with an auxiliary capacity. It is a perspective view which shows the television set in the 2nd Embodiment of this invention. It is a perspective view which shows the digital still camera in the 2nd Embodiment of this invention. It is a perspective view which shows the notebook personal computer in the 2nd Embodiment of this invention. It is a schematic diagram which shows the portable terminal device in the 2nd Embodiment of this invention. It is a perspective view which shows the video camera in the 2nd Embodiment of this invention.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described. The description will be made in the following order.
1. First embodiment (display control: an example in which a pixel is provided with a quenching capacitor)
2. Second embodiment (display control: application example to an electronic device)

<1. First Embodiment>
[Configuration example of display device]
FIG. 1 is a conceptual diagram illustrating a basic configuration example of a display device to which an embodiment of the present invention is applied.

  The display device 100 includes a write scanner (WSCN: Write SCaNner) 200, a horizontal selector (HSEL: Horizontal SELector) 300, and a power supply scanner (DSCN: Drive SCaNner) 400. Further, the display device 100 includes a pixel array unit 500. The pixel array unit 500 includes a plurality of pixels 600 arranged in an n × m two-dimensional matrix. Further, the display device 100 is provided with scanning lines (WSL: Write Scan Line) 210, data lines (DTL: DaTa Line) 310, and power supply lines (DSL: Drive Scan Line) 410.

  The scanning line (WSL) 210 and the power supply line (DSL) 410 are wired to each row of the pixels 600 and connected to the write scanner (WSCN) 200 and the power supply scanner (DSCN) 400, respectively. A data line (DTL) 310 is wired to each column of the pixels 600 and connected to the horizontal selector (HSEL) 300. Each of the scanning line (WSL) 210, the data line (DTL) 310, and the power supply line (DSL) 410 is connected to each of the pixels 600.

  The light scanner (WSCN) 200 performs line-sequential scanning of a plurality of pixels 600 arranged in a two-dimensional matrix. The write scanner (WSCN) 200 writes the data signal supplied from the data line (DTL) 310 to the pixel 600 in units of rows. That is, the write scanner (WSCN) 200 sequentially controls the timing of writing the data signal from the data line (DTL) 310 to the pixel 600 for each row.

  The write scanner (WSCN) 200 generates a control signal for sequentially controlling the timing at which the data signal is written. The write scanner (WSCN) 200 generates an ON potential for writing a data signal and an OFF potential for stopping the writing of the data signal as control signals. The write scanner (WSCN) 200 has a first off-potential for causing the pixel 600 to emit light as its off-potential and a first leak for preventing leakage of current from the data line (DTL) 310 due to the initialization of the pixel 600. A 2 off potential is generated. That is, the write scanner (WSCN) 200 generates any one of the on potential, the first off potential, and the second off potential as a control signal. The write scanner (WSCN) 200 supplies the generated control signal to the scanning line (WSL) 210.

  The write scanner (WSCN) 200 includes drivers 201 to 205 corresponding to the respective rows of the pixels 600. The drivers 201 to 205 generate control signals for writing data signals supplied from the data lines (DTL) 310 to the pixels 600 in the corresponding rows. The drivers 201 to 205 supply the generated control signals to the scanning lines (WSL) 211 to 215, respectively.

  The horizontal selector (HSEL) 300 includes a potential of a video signal, a potential of a reference signal for performing correction (threshold correction) on a threshold voltage of a driving transistor included in the pixel 600, and a quenching signal for quenching the pixel 600. One of potential (quenching potential) is selected. That is, the horizontal selector (HSEL) 300 selects one of the video signal, the reference signal, and the extinction signal. The horizontal selector (HSEL) 300 supplies the selected signal to the data line (DTL) 310 as a data signal. The horizontal selector (HSEL) 300 switches data signals based on line sequential scanning by the write scanner (WSCN) 200. The horizontal selector (HSEL) 300 is an example of a signal supply circuit described in the claims.

  The power scanner (DSCN) 400 sequentially supplies the same power signal for each of a plurality of rows (j rows: j is an integer of 2 or more). That is, the power scanner (DSCN) 400 sequentially supplies power signals to the plurality of power lines (DSL) 410. For example, the power supply scanner (DSCN) 400 supplies a power supply signal to either a power supply potential for supplying a current to the pixel 600 or an initialization potential for initializing the pixel 600 in a fixed number of rows. Switch. The power scanner (DSCN) 400 supplies the power signal to the power line (DSL) 410. The power scanner (DSCN) 400 is an example of a power supply circuit described in the claims.

  The power supply scanner (DSCN) 400 includes drivers 401 to 403 respectively corresponding to a plurality of rows (j rows). The drivers 401 to 403 generate power supply signals for pixels 600 in a certain number of rows corresponding to the drivers 401 to 403, respectively. The drivers 401 to 403 supply the generated power supply signals to power supply lines (DSL) 411 to 413, respectively. That is, the power supply lines (DSL) 411 to 413 supply the same power supply potential to the plurality of pixels 600 for each of a plurality of rows (j rows).

  The pixel 600 emits light for a predetermined period according to a voltage corresponding to a video signal from the data line (DTL) 310 based on a control signal from the scanning line (WSL) 210.

  As described above, the power supply scanner (DSCN) 400 can reduce the number of drivers of the power supply scanner (DSCN) 400 by supplying the same power supply signal to the pixels 600 in a plurality of rows. Thereby, the manufacturing cost of the display apparatus 100 can be reduced. Next, a configuration example of the horizontal selector (HSEL) 300 will be described with reference to the following diagram.

[Example of driver configuration in power scanner]
FIG. 2 is a diagram illustrating an example of a method for generating a power signal by the drivers 401 to 403 constituting the power scanner (DSCN) 400 in the display device 100. FIG. 2A is an equivalent circuit diagram illustrating a configuration example of the drivers 401 to 403 of the display device 100. FIG. 2B is a timing chart showing potential changes of the control signal line 431 and the power supply line (DSL) 410 in the configuration shown in FIG.

  FIG. 2A shows a CMOS (Complementary Metal Oxide Semiconductor) inverter in which a p-type transistor 421 and an n-type transistor 422 are connected in series with each other. Here, a power supply line (DSL) 410, a p-type transistor 421, an n-type transistor 422, a control signal line 431, and fixed potential lines 491 and 492 are shown. In this configuration, the control signal line 431 is connected to the gate terminal of the p-type transistor 421, the fixed potential line 491 is connected to the source terminal, the power supply line (DSL) 410 and the n-type transistor 422 are connected to the drain terminal. Is connected to the drain terminal. The n-type transistor 422 has a gate terminal connected to the control signal line 431 and a source terminal connected to the fixed potential line 492.

  The control signal line 431 is supplied with a control signal for switching the power signal in the power line (DSL) 410. The fixed potential lines 491 and 492 are supplied with a potential for generating a power signal of the power line (DSL) 410. The fixed potential lines 491 and 492 are supplied with a power supply potential (Vcc) for causing the pixel 600 to emit light and an initialization potential (Vss) for initializing the pixel 600, respectively.

  FIG. 2B shows potential changes of the control signal line 431 and the power supply line (DSL) 410 with the horizontal axis as a common time axis. Here, the operation of the drivers 401 to 403 in one field period (1F) will be described.

  First, immediately before the end of the previous field period, the potential of the control signal in the control signal line 431 is set to L (Low) level. Then, in one field period (1F), the potential of the control signal in the control signal line 431 changes to the H (High) level. At this time, the p-type transistor 421 is turned on (conductive) and the n-type transistor 422 is turned off (non-conductive). As a result, the power supply line (DSL) 410 is supplied with the power supply potential (Vcc) of the fixed potential line 491 as a power supply signal.

  Next, since the potential of the control signal in the control signal line 431 changes from the L level to the H level, the p-type transistor 421 is turned off (non-conducting) and the n-type transistor 422 is turned on (conducting). . Thus, the initialization potential (Vss) of the fixed potential line 492 is supplied to the power supply line (DSL) 410 as a power supply signal.

  In this manner, by providing the p-type transistor 421 and the n-type transistor 422, one of the power supply potential (Vcc) and the initialization potential (Vss) is supplied to the power supply line based on the control signal of the control signal line 431. (DSL) 410.

[Configuration example of horizontal selector]
FIG. 3 is a diagram illustrating an example of a method for generating a data signal supplied to the data lines (DTL) 311 to 313 by the horizontal selector (HSEL) 300 in the display device 100. FIG. 3A is a block diagram illustrating a configuration example of the horizontal selector (HSEL) 300 in the display device 100. FIG. 3B is a timing chart showing potential changes of the switching control lines 321 to 323 and the data line (DTL) 310 in the configuration shown in FIG.

  3A, the video signal lines 301 to 303, the reference signal line 391, the extinction signal line 392, the switching control lines 321 to 323, the switching circuits 351 to 353, the switching circuits 361 to 363, Switching circuits 371 to 373 are shown.

  Video signals (Vsig) for each of the pixels 600 in each column are supplied to the video signal lines 301 to 303 by time division. The reference signal line 391 is supplied with a reference signal (Vofs) for performing correction (threshold correction) with respect to the threshold value of the driving transistor constituting the pixel 600. A quenching signal (Vers) for quenching the pixel 600 is supplied to the quenching signal line 392. A switching control signal (Gsig) for controlling switching of the switching circuits 351 to 353 is supplied to the switching control line 321. A switching control signal (Gofs) for controlling switching of the switching circuits 361 to 363 is supplied to the switching control line 322. A switching control signal (Gers) for controlling switching of the switching circuits 371 to 373 is supplied to the switching control line 323.

  The switching circuits 351 to 353 respectively switch the presence / absence of connection between the video signal lines 301 to 303 and the data lines (DTL) 311 to 313 based on a switching control signal (Gsig) from the switching control line 321. is there. The switching circuits 361 to 363 respectively switch the presence / absence of connection between the reference signal line 391 and the data lines (DTL) 311 to 313 based on a switching control signal (Gofs) from the switching control line 322. The switching circuits 371 to 373 respectively switch the presence / absence of connection between the extinction signal line 392 and the data lines (DTL) 311 to 313 based on a switching control signal (Gers) from the switching control line 323.

  FIG. 3B shows potential changes of the switching control lines 321 to 323 and the data line (DTL) 310 having the horizontal axis as a common time axis. Originally, the potential (Vsig) of the video signal changes according to the video signal input to the display device 100, but in this example, it is assumed to be a constant potential. Here, the operation of the horizontal selector (HSEL) 300 in one horizontal scanning period (1H) will be described.

  First, immediately before the end of the previous horizontal scanning period, the potential of the switching control signal (Gsig) in the switching control line 321 is set to L level, and the potential of the switching control signal (Gofs) in the switching control line 322 is set to H level. Has been. Further, the potential of the switching control signal (Gers) in the switching control line 323 is set to L level.

  Next, in one horizontal scanning period, the potential of the switching control signal (Gsig) in the switching control line 321 changes from the L level to the H level, and the potential of the switching control signal (Gofs) in the switching control line 322 is changed from the H level. Switch to L level. Accordingly, since the video signal lines 301 to 303 and the data lines (DTL) 311 to 313 are respectively connected by the switching circuits 351 to 353, the video signal (Vsig) is supplied to the data line (DTL) 310 as a data signal. The

  Next, the potential of the switching control signal (Gsig) in the switching control line 321 switches from H level to L level, and the potential of the switching control signal (Gers) in the switching control line 323 switches from L level to H level. Accordingly, the extinction signal line 392 and the data lines (DTL) 311 to 313 are respectively connected by the switching circuits 371 to 373, and thus the extinction signal (Vers) is supplied as a data signal to the data lines (DTL) 311 to 313. The

  Then, the potential of the switching control signal (Gers) in the switching control line 323 transitions from the H level to the L level, and the potential of the switching control signal (Gofs) in the switching control line 322 switches from the L level to the H level. Accordingly, the reference signal line 391 and the data lines (DTL) 311 to 313 are connected by the switching circuits 361 to 363, respectively, and thus the reference signal (Vofs) is supplied to the data line (DTL) 310 as a data signal.

  As described above, by using the three switching circuits and the three switching control lines 321 to 323 for each of the data lines (DTL) 310, a ternary data signal can be generated.

[Example of basic operation of display device]
FIG. 4 is a timing chart regarding an example of a basic operation of the display device 100. Here, potential changes of the power supply lines (DSL) 411 and 412, the data line (DTL) 310, and the scanning lines (WSL) 211 to 214 are shown with the horizontal axis as a common time axis.

  The potential change of the data line (DTL) 310 is a potential change of the data signal generated by the horizontal selector (HSEL) 300 as described in FIG. The change in potential of the power supply lines (DSL) 411 and 412 is a change in potential of the power supply signal generated by the drivers 401 and 402 in the power supply scanner (DSCN) 400 as described with reference to FIG.

  Scanning lines (WSL) 211 to 214 are potential changes of control signals generated by the drivers 201 to 204 in the write scanner (WSCN) 200, respectively. As described above, any one of the on potential (Von), the first off potential (Voff1), and the second off potential (Voff2) is supplied to the scanning lines (WSL) 211 to 214 as a control signal. The Accordingly, three pulses 221 to 223 are supplied to the scanning lines (WSL) 211 to 214, respectively.

  The first pulse 221 is a pulse for applying the extinction signal potential (Vers) to the pixel 600 in order to extinguish the light emission of the pixel 600. The second pulse 222 is a pulse for applying the potential (Vofs) of the reference signal to the pixel 600 for threshold correction. The third pulse 223 is a pulse for correcting the mobility of the driving transistor constituting the pixel 600 and writing the video signal (Vsig). Further, each pulse is supplied to the scanning line (WSL2) 212 after 1H (horizontal scanning period) with respect to the scanning line (WSL1) 211. Further, although not shown here, each pulse is supplied to the scanning line one row below the scanning line (WSL2) 212 after 1H with reference to the scanning line (WSL2) 212.

  In this case, the power supply signal of the power supply line (DSL) 411 is simultaneously applied to the pixels 600 connected to the scanning lines (WSL) 211 to 213, and the power supply line (DSL) is connected to the pixels 600 connected to the scanning lines (WSL) 214. DSLj + 1) 412 is applied.

[Pixel configuration example]
FIG. 5 is a circuit diagram schematically illustrating a configuration example of the pixel 600 in the display device 100. The pixel 600 includes a writing transistor 610, a driving transistor 620, a storage capacitor 630, and a light emitting element 640. Here, it is assumed that the write transistor 610 and the drive transistor 620 are n-channel transistors.

  A scanning line (WSL) 210 and a data line (DTL) 310 are connected to a gate terminal and a drain terminal of the writing transistor 610, respectively. In addition, one electrode of the storage capacitor 630 and the gate terminal (g) of the driving transistor 620 are connected to the source terminal of the writing transistor 610. Here, this connection part is referred to as a first node (ND1) 650. The power supply line (DSL) 410 is connected to the drain terminal (d) of the driving transistor 620, and the other electrode of the storage capacitor 630 and the input terminal of the light emitting element 640 are connected to the source terminal (s) of the driving transistor 620. Is done. Here, this connection part is referred to as a second node (ND2) 660.

  The writing transistor 610 writes a data signal from the data line (DTL) 310 to the storage capacitor 630 in accordance with a control signal of the scanning line (WSL) 210. The writing transistor 610 applies a potential of a data signal to one electrode of the storage capacitor 630 in order to apply a voltage for causing the light emitting element 640 to emit light to the storage capacitor 630.

  The write transistor 610 holds the threshold voltage in the holding capacitor 630 by threshold correction based on the potential (Vofs) of the reference signal, and then writes a voltage corresponding to the video signal. In addition, the writing transistor 610 applies an extinction signal potential (Vers) to one electrode of the storage capacitor 630. That is, the writing transistor 610 applies a quenching signal potential (Vers) to the gate terminal of the driving transistor 620 in order to stop the supply of the driving current for causing the light emitting element 640 to emit light. Note that the write transistor 610 is an example of a write transistor described in the claims.

  The drive transistor 620 receives a power supply potential (Vcc) from the power supply line (DSL) 410, thereby causing the light emitting element 640 to generate a drive current corresponding to a voltage based on the potential (Vsig) of the video signal written in the storage capacitor 630. Output. In addition, the driving transistor 620 stops the supply of the driving current to the light emitting element 640 according to the potential (Vers) of the extinction signal given to the gate terminal by the writing transistor 610. The drive transistor 620 is an example of a drive transistor described in the claims.

  The storage capacitor 630 holds a voltage corresponding to the data signal provided by the write transistor 610. For example, the storage capacitor 630 holds a voltage corresponding to the video signal written by the write transistor 610. The storage capacitor 630 is an example of a storage capacitor described in the claims.

  The light emitting element 640 emits light according to the magnitude of the drive current supplied from the drive transistor 620. The light emitting element 640 can be realized by, for example, an organic EL element. Note that the light-emitting element 640 is an example of a light-emitting element described in the claims.

  In this example, it is assumed that the write transistor 610 and the drive transistor 620 are n-channel transistors, but the present invention is not limited to this combination. Further, these transistors may be enhancement type transistors, depletion type transistors, or dual gate transistors.

[Example of basic pixel operation]
FIG. 6 is a timing chart regarding an example of a basic operation of the pixel 600 in the display device 100. In this timing chart, the horizontal axis is a common time axis, the scanning line (WSL) 210, the data line (DTL) 310, the power supply line (DSL) 410, the first node (ND1) 650, and the second node (ND2). 660 potential changes are shown. Here, the potential change of the second node (ND2) 660 is indicated by a dotted line, and other potential changes are indicated by a solid line. In addition, the length of the horizontal axis indicating each period is a schematic one and does not indicate the ratio of the time length of each period.

  In this timing chart, the operation transition of the pixel 600 is divided into periods TP1 to TP8 for convenience. In the light emission period TP8, the light emitting element 640 is in a light emitting state. Immediately before the end of the light emission period TP8, the control signal of the scanning line (WSL) 210 is set to the first off potential (Voff1), and the data line (DTL) 310 is set to the potential of the quenching signal (Vers). The power signal of the power line (DSL) 410 is set to the power supply potential (Vcc).

  Thereafter, a new field of line sequential scanning is entered, and in the extinction period TP1, the control signal of the scanning line (WSL) 210 is switched from the first off potential (Voff1) to the on potential (Von). As a result, the potential of the first node (ND1) 650 decreases to the potential (Vers) of the extinction signal, and the potential of the second node (ND2) 660 also decreases due to the influence of the coupling by the storage capacitor 630. To do.

  Next, in the extinction period TP2, the control signal of the scanning line (WSL) 210 is switched to the second off potential (Voff2). Accordingly, the potential of the second node (ND2) 660 is reduced to the threshold potential (Vthel + Vcat) of the light emitting element 640, so that the light emitting element 640 is extinguished. At this time, the potential of the first node (ND1) 650 also decreases due to the influence of the coupling from the storage capacitor 630. Note that Vthel is a threshold voltage of the light emitting element 640, and Vcat is a potential applied to the cathode electrode constituting the light emitting element 640.

  Further, in the threshold correction preparation period TP3, the potential of the first node (ND1) 650 decreases to near the initialization potential (Vss). In this case, when the control signal of the scanning line (WSL) 210 is set to the first off potential (Voff1), current leaks from the writing transistor 610 toward the first node (ND1) 650. Therefore, the second off potential (Voff1) of the control signal of the scanning line (WSL) 210 is compared with the first off potential (Voff1) in consideration of the potential of the first node (ND1) 650 in the threshold correction preparation period TP3. To set a low potential.

  Subsequently, in the threshold correction preparation period TP3, the power supply signal of the power supply line (DSL) 410 is switched from the power supply potential (Vcc) to the initialization potential (Vss). As a result, a current flows through the driving transistor 620 toward the drain terminal, so that the potential of the first node (ND1) 650 decreases to “Vss + Vthd”. At this time, the potential of the second node (ND2) 660 also decreases. That is, the pixel 600 is initialized. Note that Vthd is a threshold voltage between the drain terminal and the gate terminal of the driving transistor 620, and is herein referred to as a threshold voltage on the drain terminal side.

  Next, in the threshold correction standby period TP4, the power signal of the power line (DSL) 410 is switched from the initialization potential (Vss) to the power supply potential (Vcc). Accordingly, a current flows through the driving transistor 620 through the other electrode of the storage capacitor 630 on the source terminal side, and the potentials of the first node (ND1) 650 and the second node (ND2) 660 are increased.

  Next, in the threshold correction period TP5, a threshold correction operation is performed. When the data signal of the data line (DTL) 310 is the potential (Vofs) of the reference signal, the control signal of the scanning line (WSL) 210 is switched from the second off potential (Voff2) to the on potential (Von). Thus, a voltage corresponding to the threshold voltage (Vth) of the driving transistor 620 is applied between the first node (ND1) 650 and the second node (ND2) 660. Thereafter, in TP6, the control signal of the scanning line (WSL) 210 is temporarily dropped to the first off potential (Voff1), and the data signal of the data line (DTL) 310 is changed from the potential of the reference signal (Vofs) to the potential of the video signal. (Vsig).

  Next, in the writing period / mobility correction period TP7, the control signal of the scanning line (WSL) 210 is raised to the ON potential (Von), so that the potential of the first node (ND1) 650 becomes the potential of the video signal (Vsig). ). As a result, a current flows from the driving transistor 620 to the parasitic capacitance 641 of the light emitting element 640, and charging of the parasitic capacitance 641 is started. On the other hand, the potential of the second node (ND2) 660 increases from the potential (Vofs−Vth) applied at TP5 by an increase amount (ΔV) due to mobility correction. That is, when the control signal of the scanning line (WSL) 210 is turned on (Von), the potential (Vsig) of the video signal is written to one electrode of the storage capacitor 630. At the same time, a potential ((Vofs−Vth) + ΔV) that is increased by the amount of increase (ΔV) by mobility correction from the potential (Vofs−Vth) applied at TP5 is applied to the other electrode of the storage capacitor 630. As a result, the storage capacitor 630 holds a voltage of “Vsig − ((Vofs−Vth) + ΔV)” as a voltage corresponding to the video signal.

  Thereafter, in the light emission period TP8, the control signal of the scanning line (WSL) 210 is set to the first off potential (Voff1). Accordingly, the light emitting element 640 emits light with luminance according to the voltage (Vsig−Vofs + Vth−ΔV) held in the storage capacitor 630. In this case, the voltage (Vsig−Vofs + Vth−ΔV) held in the storage capacitor 630 is corrected by the threshold voltage (Vth) and the amount of increase (ΔV) due to mobility correction. Therefore, the luminance of the light-emitting element 640 is not affected by variations in threshold voltage (Vth) and mobility in the driving transistor 620. Note that the potentials of the first node (ND1) 650 and the second node (ND2) 660 rise during the period up to the middle of the light emission period TP8. At this time, the potential difference (Vsig−Vofs + Vth−ΔV) between the first node (ND1) 650 and the second node (ND2) 660 is maintained.

  Although an example in which the threshold correction operation is performed once for one light emission in the light emitting element 640 has been described here, the number of threshold correction operations is not limited to this, and may be two or more. .

[Details of pixel operation status]
Next, the operation of the above-described pixel 600 will be described in detail with reference to the drawings. In the following drawings, an operation state of the pixel 600 corresponding to a period from TP1 to TP8 in the timing chart shown in FIG. 6 is shown. For convenience, the parasitic capacitance 641 of the light emitting element 640 is illustrated. Further, the writing transistor 610 is illustrated as a switch, and the scanning line (WSL) 210 is omitted.

  FIGS. 7A to 7C are circuit diagrams schematically showing the operation state of the pixel 600 corresponding to the periods TP8, TP1, and TP2. In the light emission period TP8, as shown in FIG. 7A, the power supply signal of the power supply line (DSL) 410 is set to the power supply potential (Vcc), and the drive transistor 620 supplies the drive current (Ids) to the light emitting element 640. Supply.

  Next, in the extinction period TP1, as shown in FIG. 7B, when the data signal of the data line (DTL) 310 is the potential (Vers) of the extinction signal, the control signal of the scanning line (WSL) 210 is the first. Transition from 1 off potential (Voff1) to on potential (Von). As a result, the writing transistor 610 is turned on (conductive), so that the potential of the first node (ND1) 650 is lowered to the potential (Vers) of the extinction signal. At this time, the potential of the second node (ND2) 660 also decreases due to the influence of the coupling through the storage capacitor 630 due to the potential decrease of the first node (ND1) 650.

  Subsequently, in the extinction period TP2, as shown in FIG. 7C, the write transistor 610 is turned off (non-conducted) by the transition of the control signal of the scanning line (WSL) 210 to the second off potential (Voff2). It becomes a state. Here, the light-emitting element 640 is extinguished when the potential of the second node (ND2) 660 decreases to the threshold potential (Vthel + Vcat) of the light-emitting element 640. Note that the potential of the first node (ND1) 650 also decreases to follow the potential decrease of the second node (ND2) 660.

  FIGS. 8A to 8C are circuit diagrams schematically showing the operation states of the pixels 600 corresponding to the periods TP3 to TP5, respectively.

  Subsequent to TP2, in the threshold correction preparation period TP3, as shown in FIG. 8A, the power supply signal of the power supply line (DSL) 410 is switched from the power supply potential (Vcc) to the initialization potential (Vss). As a result, a current flows through the driving transistor 620 in the direction of the power supply line (DSL) 410, so that the potential of the second node (ND2) 660 decreases. At the same time, since the first node (ND1) 650 is in a floating state, the potential of the first node (ND1) 650 is also lowered to follow the potential drop of the second node (ND2) 660. At this time, the potential difference between the potential of the first node (ND1) 650 and the initialization potential (Vss) of the power supply line (DSL) 410 is a voltage corresponding to the threshold voltage (Vthd) on the drain terminal side of the driving transistor 620. Until this occurs, the potential of the first node (ND1) 650 decreases. That is, the potential of the first node (ND1) 650 decreases to “Vss + Vthd”. In this way, the pixel 600 is initialized.

  Next, in the threshold correction standby period TP4, as shown in FIG. 8B, the power supply signal of the power supply line (DSL) 410 is switched from the initialization potential (Vss) to the initialization potential (Vcc). As a result, a small amount of current flows through the driving transistor 620 in the direction of the other electrode of the storage capacitor 630, so that the potentials of the first node (ND1) 650 and the second node (ND2) 660 slightly increase.

  In the threshold correction period TP5, as shown in FIG. 8C, when the data signal of the data line (DTL) 310 is the potential (Vofs) of the reference signal, the control signal of the scanning line (WSL) 210 is the first signal. 2. Transition from an off potential (Voff2) to an on potential (Von). Accordingly, the potential of the first node (ND1) 650 is set to the potential (Vofs) of the reference signal, so that a current flows from the driving transistor 620 to the other electrode of the storage capacitor 630, so that the second node (ND2) ) The potential of 660 increases.

  Then, when the potential difference between the first node (ND1) 650 and the second node (ND2) 660 becomes a voltage corresponding to the threshold voltage (Vth) between the source terminal and the gate terminal in the driving transistor 620. Current stops (cuts off). At this time, the potential of the second node (ND2) reaches the threshold potential (Vofs−Vth) on the source terminal side of the driving transistor 620. As a result, a voltage corresponding to the threshold voltage (Vth) of the drive transistor 620 is held in the holding capacitor 630 with reference to the potential (Vofs) of the reference signal, whereby the threshold correction operation is completed. Here, the potential (Vcat) of the cathode electrode is set so that the current from the driving transistor 620 does not flow to the light emitting element 640.

  FIGS. 9A to 9C are circuit diagrams schematically showing the operation states of the pixels 600 corresponding to the periods TP6 to TP8, respectively.

  Following TP5, in TP6, as shown in FIG. 9A, the control signal in the scanning line (WSL) 210 transitions from the on potential (Von) to the second off potential (Voff2), whereby the writing transistor 610 is obtained. Is turned off (non-conducting). Thereafter, the data signal of the data line (DTL) 310 is switched from the potential (Vofs) of the reference signal to the potential (Vsig) of the video signal. In this case, in the data line (DTL) 310, the rise of the potential (Vsig) of the video signal is moderated by the write transistors 610 in the plurality of pixels 600 connected to the data line (DTL) 310. Therefore, in consideration of the transient characteristics of the data line (DTL) 310, the writing transistor 610 is turned off until the data signal reaches the potential (Vsig) of the video signal.

  In the write period / mobility correction period TP7 subsequent to TP6, as shown in FIG. 9B, the write transistor 610 is turned on when the control signal of the scanning line (WSL) 210 transitions to the ON potential (Von). It becomes a state. As a result, the potential of the first node (ND1) 650 is set to the potential (Vsig) of the video signal. At the same time, a current flows from the driving transistor 620 to the other electrode of the storage capacitor 630, whereby the potential of the second node (ND2) 660 rises by “ΔV” from the potential (Vofs−Vth) applied at TP5. The potential difference between the first node (ND1) 650 and the second node (ND2) 660 is “Vsig−Vofs + Vth−ΔV”. Thus, the writing of the potential (Vsig) of the video signal and the adjustment of the increase amount (ΔV) by the mobility correction are performed.

  In this operation, the larger the potential (Vsig) of the video signal, the larger the current output from the driving transistor, and the greater the amount of increase (ΔV) due to mobility correction. Therefore, mobility correction according to the luminance level (the potential of the video signal) can be performed. In addition, when the potential (Vsig) of the video signal for each pixel is made constant, the amount of increase (ΔV) due to mobility correction increases as the mobility of the drive transistor increases. For example, in a pixel where the mobility of the driving transistor is large, the amount of current flowing through the other electrode of the storage capacitor is larger than in a pixel where the mobility is small, and thus the gate-source voltage of the driving transistor is lowered accordingly. Therefore, in a pixel having a high mobility of the driving transistor, the driving current supplied to the light emitting element in the light emission period is adjusted to the same level as that of the pixel having a low mobility. In this way, variation in mobility in the drive transistor for each pixel is removed.

  Next, in the light emission period TP8, as illustrated in FIG. 9C, the writing transistor 610 is turned off by the transition of the control signal of the scanning line (WSL) 210 to the first off potential (Voff1). As a result, the potential of the second node (ND2) 660 rises according to the drive current (Ids) from the drive transistor 620, and the potential of the first node (ND1) 650 also rises in conjunction with it. At this time, the potential difference (Vsig−Vofs + Vth−ΔV) between the first node (ND1) 650 and the second node (ND2) 660 is maintained by the bootstrap operation.

  Thus, after the voltage corresponding to the threshold voltage (Vth) is held in the storage capacitor 630 by the threshold correction operation, the increase amount (ΔV) due to the mobility correction operation is applied to the other electrode of the storage capacitor 630. Accordingly, variations in threshold voltage and mobility in the drive transistor 620 for each pixel 600 are canceled, so that unevenness that appears in the display image can be prevented.

  In such a display device 100, it is assumed that the potential of the second node (ND2) 660 is not sufficiently lowered in the extinction period TP1 due to the parasitic capacitance 641 of the light emitting element 640 and the parasitic capacitance of the driving transistor 620. An operation of the pixel 600 in the case where the potential of the second node (ND2) 660 is not sufficiently lowered in the extinction period TP1 is described below with reference to the drawings.

[Example in which the potential drop of the second node during the extinction period is gradual]
FIG. 10 is a timing chart illustrating the operation of the pixel 600 when the potential of the second node (ND2) 660 gradually decreases during the extinction period TP1 in the display device 100. Here, the configuration is the same as that shown in FIG. 6 except for the potential change of the second node (ND2) 660 indicated by the dotted line. Further, the potential change of the second node (ND2) 660 indicated by the chain line is the potential change of the second node (ND2) 660 shown in FIG.

  In this example, description will be given focusing on the potential change of the second node (ND2) 660 indicated by the dotted line. In the extinction period TP1, the potential of the second node (ND2) 660 decreases due to coupling from the storage capacitor 630 accompanying the potential decrease of the first node (ND1) 650. In this case, the potential of the second node (ND2) 660 does not decrease sharply but gradually decreases due to the influence of the parasitic capacitance 641 of the light emitting element 640 and the like. In the extinction period TP2, the potential of the second node (ND2) 660 gradually decreases mainly due to the discharge of the storage capacitor 630, and before reaching the threshold potential (Vthel + Vcat) of the light emitting element 640, the threshold correction preparation period TP3. Transition to.

  At this time, since the potential of the second node (ND2) 660 is higher than the threshold potential (Vthel + Vcat) of the light emitting element 640, current continues to flow through the light emitting element 640. For this reason, although the luminance gradually decreases during the extinction period TP2, the light emitting element 640 continues to emit light.

  Thereafter, in the threshold correction preparation period TP3, the power supply signal of the power supply line (DSL) 410 is switched from the power supply potential (Vcc) to the initialization potential (Vss), so that the potential of the second node (ND2) 660 is It becomes lower than the threshold potential (Vthel + Vcat). Thereby, the light emitting element 640 is completely quenched.

  As described above, when the potential of the second node (ND2) 660 gradually decreases in the extinction period TP1, the light emitting element 640 continues to emit light until immediately before the threshold correction preparation period TP3. In such a display device 100, since the power supply signals are switched simultaneously in units of a plurality of rows, as shown in FIG. 3, the extinction period TP2 is different for each pixel 600 in each row. Therefore, the light emitting element 640 is provided for each pixel 600 in each row. The period of light emission differs.

  FIG. 11 is a diagram related to a display image displayed on the display device 100 when the potential of the second node (ND2) 660 gradually decreases during the extinction period TP1 in the display device 100. FIG. FIG. 11A is a diagram illustrating an example of a display image displayed on the display device 100. FIG. 11B is a diagram illustrating the luminance characteristics in the column direction with respect to the display image. Here, it is assumed that the input image input to the display device 100 is a gray image as a whole.

  FIG. 11A shows power line common areas 451 to 453. The power line common areas 451 to 453 indicate respective areas displayed by the pixels 600 to which the same power signal is supplied. The power line common areas 451 to 453 are gradually darkened in order from the upper row. Note that the darkest color in the power line common areas 451 to 453 is the color of the input image.

  FIG. 11B shows a luminance characteristic 460. Here, the vertical axis is the horizontal line of the display image, and the horizontal axis is the luminance level. The luminance characteristic 460 is a luminance characteristic indicating a luminance level corresponding to the horizontal line of the display image shown in FIG.

  As described above, when the potential of the second node (ND2) 660 is not sufficiently lowered in the extinction period TP1, gradation is generated in the display image due to light emission of the pixels 600 in the extinction period TP2 which is different for each row. That is, since the light emission amount of the light emitting element 640 in the extinction period TP2 of the pixels 600 in each row is different, gradation is generated in the display image. For this reason, the first embodiment of the present invention to be described next is improved to reduce the gradation generated in the display image.

[Configuration example of display device]
FIG. 12 is a conceptual diagram showing a configuration example of the display device 100 according to the first embodiment of the present invention. The display device 100 includes an extinction auxiliary scanner (ESCN: Erase-auxiliary SCaNner) 700 in addition to the configuration of the display device 100 shown in FIG. Further, the display device 100 includes an extinction auxiliary line (ESL) 710. Further, the pixel 600 in the display device 100 includes an extinction capacitor 670 in addition to the configuration of the pixel 600 shown in FIG. Here, the configuration other than the extinction auxiliary scanner (ESCN) 700, the extinction auxiliary line (ESL) 710, and the extinction capacitance 670 is the same as that shown in FIG. 1 and FIG. The description here is omitted. The pixel 600 is an example of a plurality of pixel circuits described in the claims.

  In this configuration, the extinction auxiliary line (ESL) 710 is wired to each row of the pixels 600 and connected to the extinction auxiliary scanner (ESCN) 700. The extinction auxiliary line (ESL) 710 is connected to one end of the extinction capacitor 670 in each pixel 600. The other end of the extinction capacitor 670 is connected to a second node (ND2) 660 corresponding to the input terminal of the light emitting element 640 in the pixel 600.

  The extinction auxiliary scanner (ESCN) 700 supplies an auxiliary potential, which is a stop potential for surely stopping the light emission of the light emitting element 640, to one end of the extinction capacitor 670 in the extinction period for extinguishing the light emitting element 640. . The extinction auxiliary scanner (ESCN) 700 sequentially generates auxiliary potentials in units of rows based on, for example, line sequential scanning by the write scanner (WSCN) 200. In other words, the extinction auxiliary scanner (ESCN) 700 sequentially generates auxiliary potentials by providing drivers corresponding to the respective rows. Then, the extinction auxiliary scanner (ESCN) 700 supplies the generated auxiliary potential to the extinction auxiliary line (ESL) 710. The extinction auxiliary scanner (ESCN) 700 is an example of a stop potential supply circuit described in the claims.

  The extinction capacitor 670 lowers the potential of the second node (ND2) 660 by the auxiliary potential supplied from the extinction auxiliary scanner (ESCN) 700 via the extinction auxiliary line (ESL) 710. That is, the quenching capacitor 670 reduces the potential of the input terminal of the light emitting element 640 connected to the other end of the quenching capacitor 670 by applying an auxiliary potential to one end of the quenching capacitor 670. The quenching capacitor 670 is an example of the quenching capacitor described in the claims.

[Example of pixel operation]
FIG. 13 is a timing chart relating to an example of the operation of the pixel 600 according to the first embodiment of the present invention. Here, the first node (ND1) 650, the second node (ND2) 660 and the extinction auxiliary line (ESL) 710 are the same as those shown in FIG. Further, the potential change of the second node (ND2) 660 indicated by the chain line is the potential change of the second node (ND2) 660 indicated by the dotted line in FIG.

  Here, description will be made by paying attention to potential changes of the second node (ND2) 660 and the extinction auxiliary line (ESL) 710 indicated by dotted lines. In the extinction period TP1, the control signal of the scanning line (WSL) 210 is switched from the first off potential (Voff1) to the on potential (Von). At the same time, the potential of the extinction auxiliary line 710 is changed from the normal potential (Vodn) that is the potential when the light emitting element 640 emits light to the above-described auxiliary potential (Vaux) that is lower than the normal potential (Vodn). Can be switched.

  Accordingly, the potential (Vers) of the extinction signal is applied to the gate terminal of the driving transistor 620 by the writing transistor 610, and thus the potential of the first node (ND1) 650 is lowered to the potential (Vers) of the extinction signal. On the other hand, since the potential at one end of the quenching capacitor 670 is lowered to the auxiliary potential (Vaux), the charge accumulated in the parasitic capacitor 641 of the light emitting element 640 moves to the quenching capacitor 670, so The second node (ND2) 660 corresponding to the other end is lowered. Therefore, the potential of the second node (ND2) 660 is lower than the threshold potential (Vthel + Vcat) of the light emitting element 640, and thus the light emitting element 640 is completely extinguished. Note that in order to reduce the potential of the second node (ND2) 660 to the threshold potential (Vthel + Vcat) of the light emitting element 640, the auxiliary potential (Vaux) is set to a potential lower by about 1 V (volt) than the normal potential (Vodn). It can be realized by setting.

  After that, in the extinction period TP2, the control signal of the scanning line (WSL) 210 is switched from the on potential (Von) to the second on potential (Voff2). At the same time, the potential of the extinction auxiliary line 710 is switched from the auxiliary potential (Vaux) to the normal potential (Vodn). Accordingly, the potentials applied to the first node (ND1) 650 and the second node (ND2) 660 at the end of the extinction period TP1 are maintained until immediately before the start of the threshold correction preparation period TP3.

  In this manner, by providing the extinction capacitor 670 and applying an auxiliary potential (Vaux) to one end of the extinction capacitor 670 in the extinction period, the potential of the input terminal of the light-emitting element 640 is made lower than the threshold potential (Vthel + Vcat) of the light-emitting element 640. Can be lowered. That is, the potential of the second node (ND2) 660 is decreased by supplying the auxiliary potential (Vaux) when the extinction signal potential (Vers) is supplied to the gate terminal of the driving transistor 620 by the writing transistor 610. be able to.

  Thus, the light emission of the light emitting element 640 can be reliably stopped by applying the auxiliary potential (Vaux) from the extinction auxiliary scanner (ESCN) 700 to the extinction capacitor 670 during the extinction period. Furthermore, since the light-emitting element 640 can be extinguished during the extinction period, gradation that occurs in the display image displayed on the display device 100 can be suppressed. Further, since the potential difference between the normal potential (Vodn) and the auxiliary potential (Vaux) generated in the extinction auxiliary scanner (ESCN) 700 is as small as about 1 V, the manufacturing cost of the extinction auxiliary scanner (ESCN) 700 can be kept low. .

  In this example, the example in which the auxiliary potential (Vaux) is applied to one end of the extinction capacitor 670 in the extinction period TP1 by the extinction auxiliary scan (ESCN) 700 has been described, but the present invention is not limited thereto. For example, the auxiliary potential (Vaux) may be supplied to the quenching capacitor 670 for a certain period in the quenching period in which the potential of the second node (ND2) 660 is higher than the threshold potential of the light emitting element 640. Even in this case, gradation in the display image can be reduced. Although an example in which the quenching capacitor 670 is provided has been described here, an auxiliary capacitor described below may be used as the quenching capacitor 670.

[Configuration Example of Pixel with Auxiliary Capacitance]
FIG. 14 is a circuit diagram schematically illustrating a configuration example of a pixel 600 including an auxiliary capacitor. Here, an auxiliary capacitor 680 is shown in addition to the configuration of the pixel 600 shown in FIG.

  The auxiliary capacitor 680 has one end connected to the cathode electrode of the light emitting element 640 and the other end connected to the input terminal of the light emitting element 640. The auxiliary capacitor 680 is a capacitor for adjusting the rising speed (correction speed) of the potential increase of the second node (ND2) 660 in the mobility correction operation in the writing period / mobility correction period TP10 described in FIG. . The auxiliary capacitor 680 plays a role of preventing the potential rise of the second node (ND2) 660 from becoming too steep due to the small capacitance value of the parasitic capacitor 641 of the light emitting element 640. Thereby, the time setting of a mobility correction | amendment operation | movement can be performed appropriately.

  As described above, the auxiliary capacitor 680 is provided in the pixel 600 in order to suppress the potential increase degree of the second node (ND2) 660 in the writing period / mobility correction period TP10. In this structure, the cathode electrode of the light emitting element 640 in the n × m pixel 600 is integrally formed on the display screen, and the lower layer is connected by aluminum (Al) wired from the left end to the right end for each row. Each line is formed. Further, an auxiliary capacitor 680 formed for each pixel 600 is connected to each connection line wired in each row. Further, the connection line of each row is connected to the cathode electrode of the light emitting element 640 by a contact provided for each pixel 600.

  In this case, the connection between the connection line of each row and the cathode electrode of the light emitting element 640 is separated by removing the contact between each of the connection lines wired in each row and the cathode electrode of the light emitting element 640. Since the connection lines wired in each row are aggregated as one connection line at the end, an extinction auxiliary scanner (ESCN) 700 is connected to the end of the connection line. Thus, the auxiliary capacitor 680 provided in each pixel 600 can be used as the extinction capacitor 670 shown in FIG.

  In this example, the auxiliary potential (Vaux) is supplied to one end of the extinction capacitor 670 in all the pixels 600 at the same timing. Therefore, the extinction auxiliary scanner (ESCN) 700 outputs the auxiliary potential (Vaux) from the extinction auxiliary scanner (ESCN) 700 in accordance with the timing at which the extinction signal potential (Vers) is output from the horizontal selector (HSEL) 300. To do. That is, when the extinction potential (Vers) is output from the horizontal selector (HSEL) 300 during the period assigned to the plurality of pixels 600 by line-sequential scanning, the extinction auxiliary scanner (ESCN) 700 has the auxiliary potential (Vaux). ). As described above, when the auxiliary potential (Vaux) is supplied during the output period of the reference signal (Vofs) or the video signal (Vsig), the threshold correction operation or the mobility correction operation is limited to the output timing of the extinction signal (Vers). This is because it affects the pixel 600 to be performed.

  As described above, by using the auxiliary capacitor 680 as the extinction capacitor 670, the auxiliary capacitor 680 can stop the light emission of the light emitting element 640 while suppressing the potential increase in mobility correction. In addition, by diverting connection lines wired in each row, it is not necessary to newly provide an extinction auxiliary line (ESL) 710, and thus a reduction in yield of the display device 100 can be suppressed.

  Further, by supplying the auxiliary potential (Vaux) in accordance with the output timing of the extinction signal (Vers), the number of drivers in the extinction auxiliary scanner (ESCN) 700 can be reduced to one, thereby suppressing the manufacturing cost. Can do. Note that at this time, the auxiliary potential (Vaux) is applied even in the light emission period, but since the period during which the potential (Vers) of the extinction signal is output is extremely short, the influence on the light emitting element 640 is slight.

  As described above, according to the first embodiment of the present invention, even when the same power supply signal is supplied to each pixel in a plurality of rows, the auxiliary potential (Vaux) is applied to one end of the extinction capacitor 670 during the extinction period. By providing the above, gradation appearing in the display image can be reduced. Thus, the cost can be reduced by reducing the number of drivers of the power supply scanner (WSCN) 400 while maintaining the reproducibility of the input image.

  Note that the display device according to the first embodiment of the present invention has a flat panel shape, and is applied to various electronic devices such as digital cameras, notebook personal computers, mobile phones, video cameras, and the like. Can do. Further, the present invention can be applied to a display of an electronic device in any field that displays a video signal input to the electronic device or a video signal generated in the electronic device as an image or video. Examples of electronic devices to which such a display device is applied are shown below.

<2. Second Embodiment>
[Application example to electronic equipment]
FIG. 15 is an example of a television set according to the second embodiment of the present invention. This television set is a television set to which the first embodiment of the present invention is applied. This television set includes a video display screen 11 including a front panel 12, a filter glass 13, and the like, and is manufactured by using the display device according to the first embodiment of the present invention for the video display screen 11. .

  FIG. 16 is an example of a digital still camera according to the second embodiment of the present invention. This digital still camera is a digital still camera to which the first embodiment of the present invention is applied. Here, a front view of the digital still camera is shown above, and a rear view of the digital still camera is shown below. This digital still camera includes an imaging lens 15, a display unit 16, a control switch, a menu switch, a shutter 19, and the like, and is manufactured by using the display device according to the first embodiment of the present invention for the display unit 16. .

  FIG. 17 is an example of a notebook personal computer according to the second embodiment of the present invention. This notebook personal computer is a notebook personal computer to which the first embodiment of the present invention is applied. The notebook personal computer includes a main body 20 including a keyboard 21 that is operated when characters and the like are input, and a main body cover includes a display unit 22 that displays an image. The display according to the first embodiment of the present invention. It is manufactured by using the device for the display portion 22.

  FIG. 18 is an example of a mobile terminal device according to the second embodiment of the present invention. This portable terminal device is a portable terminal device to which the first embodiment of the present invention is applied. Here, the opened state of the portable terminal device is shown on the left side, and the closed state of the portable terminal device is shown on the right side. The portable terminal device includes an upper housing 23, a lower housing 24, a connecting portion (here, a hinge portion) 25, a display 26, a sub display 27, a picture light 28, a camera 29, and the like. The portable terminal device is manufactured by using the display device according to the first embodiment of the present invention for the display 26 or the sub display 27.

  FIG. 19 is an example of a video camera according to the second embodiment of the present invention. This video camera is a video camera to which the first embodiment of the present invention is applied. This video camera includes a main body 30, a lens 34 for photographing an object on a side facing forward, a start / stop switch 35 at the time of photographing, a monitor 36, and the like, and includes the display device according to the first embodiment of the present invention. It is manufactured by using it for the monitor 36.

  The embodiment of the present invention is an example for embodying the present invention, and has a corresponding relationship with the invention-specific matters in the claims as described above. However, the present invention is not limited to the embodiments, and various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Display apparatus 200 Light scanner 201-205, 401-403 Driver 210-215 Scan line 300 Horizontal selector 310-313 Data line 321-323 Switching control line 351-353, 361-363, 371-373 Switching circuit 391 Reference signal line 392 extinction signal line 400 power supply scanner 410-413 power supply line 421 p-type transistor 422 n-type transistor 431 control signal line 491-492 fixed potential line 500 pixel array portion 600 pixel 610 writing transistor 620 driving transistor 630 holding capacitor 640 light emitting element 641 parasitic Capacity 670 Quenching capacity 680 Auxiliary capacity 700 Quenching auxiliary scanner 710 Quenching auxiliary line

Claims (7)

A plurality of pixel circuits;
A stop potential supply circuit for supplying a stop potential for stopping light emission of the plurality of pixel circuits,
Each of the plurality of pixel circuits is
A holding capacitor for holding a voltage corresponding to the video signal;
A drive transistor for supplying a current according to the voltage held in the holding capacitor;
A light emitting element that emits light in response to a current supplied from the driving transistor;
A write transistor for writing a voltage corresponding to the video signal to the storage capacitor after applying a quenching potential for quenching the light emitting element to the gate terminal of the drive transistor;
A quenching capacitor that lowers the potential of the input terminal of the light emitting element connected to the other end of the quenching capacitor by applying the halt potential supplied by the stop potential supply circuit to one end of the quenching capacitor,
The display device in which the stop potential supply circuit supplies, as the stop potential, one end of the quenching capacitor, which is lower than the potential when the light emitting element emits light during a quenching period for quenching the light emitting element. A power supply circuit for supplying the same power supply potential for each of the plurality of rows to the plurality of pixel circuits;
The display device according to claim 1, wherein the driving transistor supplies a current corresponding to a voltage held in the storage capacitor by receiving the power supply potential. A signal supply circuit that outputs the extinction potential in a period allocated by line-sequential scanning to the writing transistor of each of the plurality of pixel circuits;
The display device according to claim 1, wherein the stop potential supply circuit supplies the stop potential when the extinction potential is output from the signal supply circuit to the plurality of pixel circuits in the extinction period.   The display device according to claim 1, wherein the stop potential supply circuit supplies the stop potential when the extinction potential is applied to the gate terminal of the drive transistor by the write transistor.   The display device according to claim 1, wherein the light emitting element includes an organic electroluminescence element.   The display device according to claim 1, wherein the extinction capacity is a capacity for adjusting a correction speed when correcting the mobility of the driving transistor. A plurality of pixel circuits;
A stop potential supply circuit for supplying a stop potential for stopping light emission of the plurality of pixel circuits,
Each of the plurality of pixel circuits is
A holding capacitor for holding a voltage corresponding to the video signal;
A drive transistor for supplying a current according to the voltage held in the holding capacitor;
A light emitting element that emits light in response to a current supplied from the driving transistor;
A write transistor that writes a voltage corresponding to the video signal to the storage capacitor after applying a quenching potential for quenching the light emitting element to the gate terminal of the drive transistor;
A quenching capacitor that lowers the potential of the input terminal of the light emitting element connected to the other end of the quenching capacitor by applying the halt potential supplied by the stop potential supply circuit to one end of the quenching capacitor,
The stop potential supply circuit is an electronic device that supplies, as the stop potential, one end of the quenching capacitor that has a lower potential than the potential when the light emitting element emits light during a quenching period for quenching the light emitting element.